feasibility study on rehabilitation of kesc gas turbine
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N E DO-I C —0 0 E R 4 1 4
Feasibility Study on Rehabilitation of KESC Gas Turbine Power Plant
March, 2001
02 0005 3
New Energy and Industrial Technologies I elopment Organization (NEDO)I Entrusted to Hitachi, Ltd.04-3 •
Feasibility Study on Rehabilitation of KESC Gas Turbine Power PlantHitachi, Ltd.
March 2001
Study purpose;Regarding the gas turbine power stations around Karachi, Pakistan, the high cost of gas turbine fuels and the decline in power generation efficiency due to the secular deterioration of the current equipment are considered problematic. These are major factors that increase the emissions of carbon dioxide, which is a worldwide problem. This project aims to study the project comprehensively, in terms of the carbon dioxide reducing effect, profitability, spreading effect and other factors by conducting a conceptual design of the project for the gas turbine power stations, in an attempt to connect it to the Clean Development Mechanism (COM) to be implemented with developing countries.
NEDO-I C— 00 E R 4 1
Feasibility Study on Rehabilitation of KESC Gas Turbine Power Plant
March, 2001
New Energy and Industrial Technologies Development Organization (NEDO)
Entrusted to Hitachi, Ltd.
Preface
This report summarizes the results of the "Rehabilitation of the KESC's Gas Turbine Power Plants," a basic survey for joint implementation and other operations of Fiscal 2000 commissioned by the New Energy and Industrial Technology Development Organization (NEDO) to Hitachi, Ltd.
In Karachi, the Islamic Republic of Pakistan (abbreviated as Pakistan), the Karachi Electric Power Supply Corporation (KESC) in charge of supplying electric power to Karachi does not have enough supply capacity to meet the yearly rising population and demand of electric power. The organization is therefore obliged to implement systematic outages and other supply limitations.
Many of the thermal power plants owned by the KESC are more than ten years old. Since they have not been fully checked or repaired during that period, they have declined in output and power generation efficiency due to secular deterioration, resulting in their power supply capacity going down.
The decline in power generation efficiency is increasing fuel consumption, that is, increasing the emissions of carbon dioxide, which is the greenhouse gas to be generated during combustion. The urgent need for the time being is to increase power generation efficiency and reduce emissions of carbon dioxide by rehabilitating the thermal power plants.
From that viewpoint, we conducted a basic survey of the rehabilitation of the gas turbine power generation facilities owned by the KESC and summarized the results in this report. This survey is also designed to explore leading projects that may connect to Japan's future efforts of the CDM (Clean Development Mechanism).
During the three field surveys, the KESC's head office and its power stations welcomed our survey team warmly, provided the necessary information, and gave support in our survey. We thank them sincerely as well.
March 2001
Hitachi, Ltd.
CONTENTS
Preface
CONTENTS
Overview
Notation
Chapter 1 Basic items of the Project
1. Status of Pakistan1.1 Political, economical and social status .................................................................. 1-11.2 Energy status ........................................................................................................ 1-41.3 Need of COM project .............................................................................................. 1-11
2. Necessity of energy-saving technology in the proposed fields of business ................. 1-12
3. Significance, needs and effect of the project and the spread of theachievements to similar industries.................................................................................. 1-13
Chapter 2 Materialization of the Project Plan
1. Project plan1.1 Overview of the regions to be covered in the project ............................................ 2-11.2 Contents of the project............................................................................................ 2-21.3 Targeted greenhouse gases and other matters ..................................................... 2-3
2. Outline of the implementation site2.1 Interest level at the implementation site.................................................................. 2-42.2 Equipment and facilities condition of the implementation site
(outline, specification, and operation condition) .................................................... 2-52.2.1 KORANGI GT PS ............................................................................................. 2-52.2.2 SITE GT PS ...................................................................................................... 2-622.2.3 Operation status ................................................................................................ 2-1152.2.4 Degradation status ............................................................................................. 2-115
2.3 Project executive capacity of the implementation site ........................................... 2-1192.4 Project situation and specifications of equipment and facilities
after replacing the existing Gas Turbines with advanced ones ............................. 2-1222.4.1 System and major equipment ........................................................................... 2-1222.4.2 Instrumentation and control plan ...................................................................... 2-1812.4.3 Site layout plan ................................................................................................. 2-190
2.5 The range of funds, equipment, service, etc. to be supplied by therespective parties for the implementation of this project ....................................... 2-202
2.6 Prerequisites and problems for the implementation of this project.......................... 2-2032.7 Project implementation schedule ...........................................................................2-204
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3. Materialization of the funding proposal3.1 Funding proposal for the project implementation ...................................................2-2063.2 Fund raising prospects ...........................................................................................2-2073.3 In the implementation of the project .......................................................................2-207
4. Issues related to CDM conditions4.1 Coordination items with Pakistan side to realize the CDM project .........................2-2084.2 Possibility of forming a consent to make this project as CDM ................................2-209
Chapter 3 Effect of the Project1. Energy saving effect
1.1. Technical background for the energy saving effect ............................................... 3-11.2 Baseline to calculate the energy saving effect ...................................................... 3-21.3 Specific quantity, observed period, and accumulated quantity of
the energy-saving effect.................................................. 3-41.4 A specific method of monitoring the effect of the energy-saving ........................... 3-5
2. Greenhouse gas reduction effect2.1 Technical reasons for the greenhouse gas reduction effect .................................. 3-122.2 The baseline as the basis for calculating the greenhouse gas
reduction effect ....................................................................................................... 3-122.3 Specific quantity, observed period, and accumulated quantity of
the greenhouse gas reduction effect ...................................................................... 3-122.4 A specific method of monitioring the greenhouse gas reducing effect .................. 3-13
3. Influence on productivity3.1 Improvement of productivity..................................................................................... 3-143.2 Reduction of energy consumption rate.................................................................... 3-14
Chapter 4 Profitability1. Economical effect of the collection on investment
1.1 Prerequisites............................................................................................................ 4-11.2 Calculation results.................................................................................................... 4-4
2. Cost effectiveness of the project2.1 Prerequisites............................................................................................................ 4-82.2 Calculation results.................................................................................................... 4-8
Chapter 5 Verification of the progress effect1. Possibility of the progress in the country to introduce the objective
technology by the project1.1 Overview of the progress possibility regions ......................................................... 5-11.2 Results of the field survey ...................................................................................... 5-4
2. Effect under consideration of progress2.1 Energy saving effect ............................................................................................... 5-62.2 Greenhouse gas reduction effect ........................................................................... 5-11
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Chapter 6 Influence on other sectors1. Natural gas product
1.1 Background ............................................................................................................ 6-11.2 Natural gas production capacity ............................................................................. 6-31.3 Natural gas production............................................................................................. 6-3
2. Natural gas utilization trends2.1 Natural gas demand ............................................................................................... 6-52.2 Natural gas demand and supply balance ............................................................... 6-62.3 Natural gas prices .................................................................................................. 6-6
3. Laying of natural gas pipelines ...................................................................................... 6-73.1 Overview of the natural gas distributors ................................................................. 6-73.2 Installation of natural gas pipelines ........................................................................ 6-9
4. Future focus of natural gas utilization4.1 Background and history of the task force ............................................................... 6-104.2 Proposal contents ................................................................................................... 6-10
Conclusion
References
List of technical surveyors
IV
Overview
Here is an overview of the survey report on the "Rehabilitation of KESC's Gas Turbine Power Plants," a basic survey for implementing the COM for fiscal 2000.
Chapter 1 (basic items of the project)
This chapter describes the political, economic, and social status of Pakistan, our host country. We will then describe the demand and supply status of energy, particularly electric power, mainly Pakistan's supply system of electric power. We will also describe the necessity of the energy-saving technology and the significance of the project in Pakistan.
Chapter 2 (materialization of the project plan)
This chapter will describe the project plan, give an overview of the implementation site, and describe matters related to the funding proposal and the COM. The section about the overview of the implementation site will describe the status and the post-remodeling specifications of KESC and the implementation site based on the field surveys, mainly the technical aspects of the system, instrumentation, and arrangement. The section about the funding proposal will describe the ideas of KESC and the Pakistani Government (the guarantor of funds) about the source of funds and the prospects of fund-raising. The section about matters related to the COM summarizes the current ideas of the Pakistani Government and KESC.
Chapter 3 (Effects of the project)
This chapter will describe the effects of the project in terms of the energy-saving effect and the greenhouse gas reducing effect regarding the two cases described in 2.4 of Chapter 2 and listed below.
Case 1: The gas turbines and dynamos will be replaced.
Case 2: The gas turbines will be replaced, and the dynamos will be rewound and reused.
Regarding the energy-saving effect and the greenhouse gas reducing effect, we will establish technical reasons for the energy-saving effect, establish a baseline as the basis for calculations, and conduct a quantitative assessment based on the baseline. We will then describe the results. We will also describe how to monitor such effects.
As for productivity, we will describe the effects of this project on productivity and the results of an observation in terms of productivity and energy consumption rate.
Chapter 4 (Profitability)
This chapter describes the profits that KESC is expected to obtain from the project. The section about the economic effect of the return on investment will set conditions for the case when this project is financed by special environmental yen credit and describe the results of a study of additional profits on initial investment. The section about the cost-
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effectiveness of the project will describe the cost-effectiveness of the project, based on theenergy-saving effect and the greenhouse gas reducing effect calculated in Chapter 3.
Chapter 5 (Checkup of the spreading effect)
This chapter will describe the spreadability of the technologies for energy-saving and reducing greenhouse gases to other segments, in terms of the two cases listed below.
(1) The spread of Case 1 (replacement of the gas turbines and dynamos) presented in 2.4 of Chapter 2 to the gas turbine power plants owned by electric power companies other than those of KESC.
(2) The spread of such technologies to the steam thermal power plants owned by KESC.
For each of the aforementioned cases, we selected power stations to be considered, surveyed the current condition of the thermal power plants, and conducted a quantitative assessment of the energy-saving effect and greenhouse gases. This chapter describes the results.
Chapter 6 (Impact on other segments)
This chapter describes the supply system of Pakistan for natural gases, which is the basis for the energy-saving effect and the greenhouse gas reducing effect to be obtained by implementing the project.
In addition, we attached as a reference material a summary of the previous problems regarding the steam power plants owned by KESC. The steam thermal power plants have problems similar to those of the gas turbine power plants and need to be rehabilitated soon.
To realize this project, the fund raising by yen credit meets the intention of the Pakistani Government and KESC. Hereafter, the policies of KESC and Pakistani Government will be deliberated and their future prospects towards the fund raising by yen credit will be sought. Other methods of fund raising are severer in the aspects of interest rates and repayment conditions than yen credit, but the possibility of fund raising will be considered through the aid of the local Japanese corporations (trading company, etc ).
VI
Notation
Units
The units must as a rule conform to the International System of Units (SI) as per JIS Z 8203 and its usage. However, the Pakistanis still use the notation of yards and pounds. The units indicated below are therefore used in some parts of this document. Both the SI and the yard/pound notations are indicated whenever necessary.
- Examples
ft (length), psi (pressure), °F (temperature in Fahrenheit)
Notes:Documents from Pakistan use notations as listed below as the units of volume and heat quantity. Please note that they are distinguished from the prefix M (Mega, representing million) used in the SI units.(1) MCF (Thousand Cubit Feet), MBtu (Thousand British thermal unit)
M is the Roman numeral representing 1,000. 1 MCF = 28.317 m3, 1 Mbtu = 1,055 kJ
(2) MMCF (Million Cubic Feet), MMBtu (Million Btu)MMCF and MMBtu represent 1,000 times the NCF and MBtu respectively.
(3) MMCFD (Million Cubic Feet per Day)1 MMCFD = 28,317 m3/day =1,180 m3/h
This document also uses non-SI units tolerated by academic societies, laws and other authorities.
- Examples°C (temperature): The JIS standards tolerate this unit according to the Electric Utility
Law.kg/cm2 (pressure): The practices of the power industry are considered while
conforming to the Electric Utility Law. m3N (gas volume in a standard state): As per the Electric Utility Law.
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Chapter 1 Basic items of the Project
Karachi is the most populated economical city of Pakistan. Karachi suffers a chronic power shortage and is obliged to impose limitations on its power supply. In this chapter, it is described the political, economical, and social status of Pakistan, our host country. It is presented also the demand and supply status of energy, particularly electricity, mainly on Pakistan's power supply resources.
It is described the necessity to introduce energy saving technology and the meaning of this project in Pakistan.
1. Status of Pakistan
Pakistan is, as its formal name (The Islamic Republic of Pakistan), a country of Muslims having Islam as its national religion. It consists of four provinces (Punjab, Sindh, North West Frontier, and Baluchistan) and the Kashmir region. Its capital is Islamabad. Its territory is about double that of Japan, the country has regions having a wide variety of climactic features, ranging from a mountainous area capped with snow in the winder in the north to a flat area in the area along the Indus River where it rarely goes below 20°C even in the winter in the south.
Pakistan is the birthplace of the Indus civilization and has since ancient times been at an important point in trade. It is bounded in the west by Iran and Afghanistan, north by China, east by India, and south by the Arabian Sea.
Pakistanis generally speaks Urdu, one of Arabian language, and English. In the cities, English is widely mentioned and most of the intellectuals can speak English fluently.
1.1 Political, economical, and social status
(1) Political status
In August 14, 1947, Pakistan was created by separating itself from its neighbor, India, for religious differences. The key person in the creation of the country, Muhammad Ali Zinnah (died in 1958) is admired as Quaid e Azam (meaning "The Great Leader"). In fact, his images are posted up in public facilities, companies, shops, etc.
Pakistan used to be civil administration, and its politics conducted by its prime minister However, its relations with India, particularly the issue of attribution of the Kashmir region, make the Pakistanis highly aware of defence issues and the military has a strong right to speak in politics. In 1999, the then prime minister Nawaz Sharif conflicted in views with the military chief, Gen. Pervez Musharraf, and conspired to dismiss the general from his post ind replace him with a military man having a strong political color. In response to that movement, a military coup occurs on October 13, so that civil administration was suspended and taken over by the military. Military
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(2) Economical status
The monetary unit in Pakistan is Pakistan Rupee (Rs.) and Paisa (Ps.). One Rupee is equivalent to 100 Paisa. However, the rising commodity prices for the past few years have promoted foods and other general consumer goods to be on Rupee standard, with Paisa rarely used. Most of the money in the market is paper money: 1,000, 500, 100, 50, 10, 5 and 1 Rupee bills being issued. Coins are available in 1 Rupee, along with 50, 10, 5, and 1 Paisa. For the aforementioned reason, however, no coins other than 1 Rupee coins are often seen now.
In 1998, Pakistan performed atomic bomb explosion test to show rivalry against India's test. This country thus had an atomic power. This aroused the antipathy of the United States and other countries, resulting in the country undergoing a freeze of new assistance programs and other economic sanctions. Some economic sanctions are still ongoing, but the situation is going for the better, as seen in the IMF's having resumed its assistance.
The fiscal year of Pakistan is from July through June of the next year. In fiscal 1997 (from July, 1996 through June, 1997), the country's gross domestic product (GDP) had a real growth rate of 5.4%. In fiscal 1998, the economic sanctions ongoing at that time resulted in a decline to 3.1%, but fiscal 1999 saw a rate of 4.6%, showing a trend toward recovery.
Pakistan uses floating rates. At the time of our survey, the exchange rate was about 60 rupees against the dollar. About a decade ago, it was about 30 rupees against the dollar, but the increase in foreign debt and the progress of inflation during the administration of prime ministers Bhutto and Sharif resulted in the current situation.The rate of increase in consumer prices was as high as 7.8% in fiscal 1998. However, since the rate was 11.8% in the previous fiscal year, one can safely say that inflation is fading out.
The current 9th Five-Year Plan stresses the privatization of state-run firms and direct investment from foreign countries. In privatization, the high priorities are occupied by petrol, gas, and electricity.
The Pakistani economy has a problem with the collection of taxes. Today, payers of direct taxes are said to number about 1.2 million, accounting for less than 1% of the population. This is partly because it is difficult to impose taxes on many of the nationals, since the average income of ordinary workers is about 2,000 rupees (about 35 US dollars) per month. However, the non-payment of taxes and rampant tax evasions due to the low awareness of tax payment are putting pressure on governmental finance. The government is attempting to increase its tax revenues through import duties (up to 200%), along with consumption taxes and other indirect taxes, while inciting the nationals to pay taxes. However, this problem needs prompt improvement, together with the non-payment of electric charges and other public utility charges to be described later in this report.
administration is still going on but the general has promised to give a general electionin 2002 and shift to civil administration.
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(3) Social status
Pakistan is the world's ninth populated country. In 1999, it was estimated to have a population of about 140 million (with a population growth rate of 2.9% annually). Of that, some 13 million live in the city of Karachi, the city which we surveyed in the present survey. The population of Karachi is said to be rising at 5% annually but no accurate statistics have been collected on the population.
With Islam teaching that all people are equal in the presence of the only God (Allah), Pakistan has no such caste system as that of India. The country is meritocratic: people are recognized by their abilities. However, in reality, there is a great difference between the rich and the poor. The differences between the rich and the poor are evident in the differences in educational opportunities and friendly relationships, and one cannot deny that a hierarchy is thus formed.
Since it came under military control, Pakistan has been better policed, with an allegedly lower crime rate than before. On the other hand, the country still suffers political and religious conflicts, with incessant incidents. The conflicts of sects are those between Shiites and Sunnites, which are witnessed in other countries as well. Pakistan also has a problem peculiar to the country: political conflicts between Shiites and Sunnites on the one hand and Muhajirs (Muslims who migrated from India at the time of independence and who have formed a Muhajir Qaumi Movement (MQM), or a Muhajir Nationalist Movement. Several strives and conflicts have occurred around Karachi (which we surveyed in this project) and various parts of the Sindh province. These regions are designated as regions where "tourists should be alert" by the Government of Japan.
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1.2 Energy status
Pakistan is an energy resource superpower. It has hydroelectric power in the north, coal in the south, and oil and natural gases in the middle, thus enjoying a rich stock of energy sources. Table 1.2-1 shows the amounts of energy resources of Pakistan as of June, 1999.
Table 1.2-1 Energy resources of Pakistan
Resource QuantityOil 253.46 x 10s bbl (40.3 X 106 m3)Natural gas 19,000X1012 CF (538X 109 m3)Coal 185X 109 tonHydro 38,000 MW
(1) Supply and demand of energy
Table 1.2-2 shows the amounts of supply and consumption of energy in fiscal 1999 (July, 1998 through June, 1999).
Table 1.2-2 Energy supply and consumption in 1998-99
Resource Energy supply Energy consumptiontoe* Share (%) toe* Share (%)
Oil 17,858,178 42.8 *11,509,120 47.6Natural gas 16,109,161 38.6 7,480,382 31.0LPG 180,559 0.4 254,181 1.1Coal 2,147,108 5.2 1,362,823 5.7Hydro power 5,358,258 12.8 - -
Nuclear power 67,869 0.2 - -
Power consumption - - 3,509,573 14.6Total 41,721,134 100.0 24,116,079 100.0
*: ton of energy **: Does not include consumption for electric power orstockpiles.
Energy supply rose 3.9% in 1999 from the previous year, reaching 4,172 tons in terms of petrol. Production of natural gases increased 6.8%, with other energy sources risen slightly. Nuclear power generation went down by 24%, because the Karachi Nuclear Power Station was suspended for a full-scale inspection.
Recent rends show that the rise in energy consumption surpasses the rise in the supply. The energy consumption for the past three years rose 4.6% as opposed to 4% in the GDP. The quickest rise was in the petrochemical sector, which rose as much as 7.1%. The rise in power consumption slowed down, which is due to the spread of cogeneration and the high electricity charges, along other factors.Pakistan's demand for industrial energy is projected to double during the past decade.
Despite its rich energy resources, the country produces small quantities of crude oil and coal. Imports of petrol products, particularly those of fuel oil, are going up, which is one factor that is putting pressure on Pakistani economy.
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(2) Power status
1) Styles of electric utilities
Pakistan is provided with electricity by the following organizations:
(D Water and Power Development Authority (WAPDA)
As a public corporation, WAP DA develops water resources and builds, opreat4s, and maintains equipment for transmitting and distributing power to the entire territory of Pakistan, except for the Karachi region, while covering some 80% of the electricity consumption of Pakistan. Power distribution is controlled by eight regional electric bureaux.
(D The Karachi Electric Power Supply Corporation (KESC)
The Pakistani government owns 80% of the outstanding shares of KESC.It is in charge of building, operating, and maintaining the electric power facilities in the Karachi region. In addition to the gas turbine power plants which we surveyed in this project, the company owns steam thermal power plants. Chapter 2 will describe KESC in detail.
(D Independent Power Producers (IPPs)
Companies based on private or foreign capital have built mainly thermal power plants and sell electricity to WAP DA and KESC. The plan has been implemented since 1985, with numbers of such projects having risen quickly during the past three years. The share of IPPs in thermal power generation rose from 37% in fiscal 1998 to 48% in fiscal 1999. Much of the power generated thermally is based on furnace oil as the fuel.
In addition to the above, one agency complements the supply of power for the Karachi region. It is the Karachi Nuclear Power Plant (KANUPP), which runs nuclear power plants. The Karachi Nuclear Power Plant is currently suspended for a full-scale inspection.
2) Supply and demand of power
Fig. 1.2-1 shows where the main power stations are located in Pakistan. Hydroelectric power plants concentrate in the northern mountainous areas. There is only one nuclear power plant. The generated energy of Pakistan in 1999 was 65,402 GWh, of which 65.5% was thermal, 34% hydroelectric, and 0.5% nuclear.
KESC generated 4,834 GWh (at site) between July, 1998 and March, 1999. However, due to lack of power supply, KESC purchased a total of 2,813 GWh from WAPDA, KANUPP, and IPPs, along with other power companies. The reasons for that will be described in detail in Chapter 2.
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3) Power transmission equipment
Most of the power transmission equipment in Pakistan is controlled by WAP DA as described above. Fig. 1.2-2 shows a system diagram of the power transmission line. WAPDA's key power transmission network consists of transmission lines of 500 kV and 220 kV. The 500 kV transmission line connects the hydroelectric power plants in the north to the load center in the south of Pakistan. As of 1997, WAPDA's 500 kV transmission line had a total extension of 2,803 km, while its transmission line of no more than 220 kV had a total extension of 23,000 km.
KESC's power transmission system was in small scale and no transmission line of 500 kV. The transmission line of no more than 220 kV had a total extension of 867 km. KESC is planning to extend its power transmission line, but the plan hit a setback for lack of funds. Our present survey revealed some sections equipped with no transmission lines in and around Karachi, although the poles for power transmission had already been erected. An example is shown in Fig. 1.2-3.
Thermal Power Station
rfl-i Hydro Power Station
Nuclear Power Station IslamabadKALABAGH(H). A, Rawalpindi
CHASHMA(N)
MID COUNTRY (T)
| DUKI (T)
QUETTA (T)
MANGLA(H)
RASUL(H)
SHAHDARA(T)
FAISALABAD (T)
' KOT ADU(T)
MULTAN (T)i) MULTAN
GUDDU(T)
Sukkur t .vS SUKKUR (T)
WEST WHARF (T) -------KOTRI(T)
— JAMSHORO(T)
- HYDERABAD (T)Hyderabad
KANUPP (N)
BIN QASIM(T)
Fig. 1.2-1 Major Power Stations in Pakistan
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(3) Planning of electric power development
WAPDA's planning of electric power development emphasizes the optimal use of hydroelectric power mainly. WAP DA is not scheduled to build a new thermal power plant, leaving all such work to IPPs.
KESC is now not authorized to carry out a new plan of electric power development. The top-priority challenge is to improve itself financially. Hopes run high for such measures as cutting the fuel expenses by increasing the efficiency of installed equipment.
(4) Fuel prices
The fuels used in Pakistan for electric power are fuel oil and natural gas. Table 1.2-3 indicates the fuel prices in July, 2000.
Table 1.2-3 Fuel Prices in Pakistan
Fuel Type Unit Price
FuelOil
HSDO (High Speed Diesel Oil) Rs./Litre 14.33LDO (Light Diesel Oil) Rs./Litre 11.20Kerosene Rs./Litre 13.13Furnace Oil Rs./kg 8.257
Natural Gas (Commercial) Rs./MCF (Rs./nf) 178.56 (0.634)
As described in (1), the country relies on imports from other countries for fuel oil. The rise in crude oil prices for the past few years has resulted in the fuel oil prices several times as high as before. Furnace oil, for example, went up from about 2,500 rupees per ton in 1995 to 8,250 rupees per ton in 2000, thus rising 3.3-fold. Natural gases are homemade, so they show only a low increase rate. The Government of Pakistan has positively been promoting fuel conversion (from oil to natural gas) in the thermal power plants. The status of natural gases will be described in detail in Chapter 6.
(5) Electric power charges
The electric power charges in Pakistan are subject to different systems depending on the category of demand, consumption, supply voltage and other factors. The power charge consists of a basic charge (capital charge + power consumption charge) and a fuel adjustment charge. The fuel adjustment charge is calculated on the basis of the average fuel expenses for 12 months until two months before the month of billing.
The power charges to be paid by each customer are as follows:
(Basic charge) + (fuel adjustment charge) + [additional charge (0.07 rupees/kWh to 5.37 rupees/kWh) + (10.4% of the sum of the basic charge and the fuel adjustment charge)
Provided that the customers as described below are subject to a different billing system.
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1) Tribes living in any of the federally controlled regions (mainly the western regions of Pakistan): fixed charge
2) Customers for residential purposes with consumption rates of up to 300 kWh annually: fixed charge
3) Customers for residential purposes with consumption rates have less than 50 kWh, and customers for industrial purposes with subscribed power consumption rates of less than 40 kWh: free of charge
Customers for industrial purposes have been subject to a time-zone-specific billing system since 1993. Table 1.2-4 summarizes the system of these power charges.
Not all customers pay their charges according to this billing system, and many of them actually do not pay their charges. KESC estimates that it manages to collect the charges from less than 53% of the customers.
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Table 1.2-4 Electricity Prices of Pakistan1Tariff Category
FixedCharge
(Rs/kWh)
Energycharge
(Rs/kWh)PAS
(Rs/kWh)
Surcharge (18.4% of
supply charges)
Additionalsurcharge(Rs/kWh)
General Supply Tariff
Up to 50 units (S50 kWh) 0.54 0.07 0.73For consumption above 50 unitsFor first 100 units (51-100 kWh) 0.68 0.07 1.02For next 200 units (101-300 kWh) 0.77 0.15 1.73For next 700 units (301-1000 kWh) 1.10 0.75 2.99For next 3000 units (1001-4000 kWh) 1.47 0.75 3.85Above 4000 units (>4000 kWh) 1.47 0.75 4.36
MinimumCharges
a) For single phaseb) Three phase
Rs.0.45Rs.1/-Plus Rs.0.25/kWh for load above5 kWh
Flat rate for FATA (Rs. per House) 0.u9 j 5.37General Supply Tariff (A-2)For first 100 units 2.17 0.75 3.46Above 100 units 2.41 0.75 3.56
MinimumCharges
a) Single phase Rs.1.5/-b) Three phase Rs.3/-plus Rs. 0.3 per kWh for land
above 10 kWhIndustrial Supply Tariff
B1- (Up to 40 kWh) 1.19 0.75 2.59Minimum ch land >2u 40
arge Rs.0.7/kWh pm plus 0.2 kWh & Rs.0.9/kWh pm kWh
B2- (41-500 kWh) 2 0.68 0.75 2.33B2- (Off peak) 2 0.58 0.75 2.18B2- (Peak) 2 1.36 0.75 2.89B3- Up to 5000 kWh (Normal) 2.9 0.67 0.75 1.57B3- (Off peak) 2.9 0.53 0.75 1.16B3- (Peak) 2.9 1.35 0.75 1.82Rawat H.V. Testing Lab. 1.26 0.75 1.57B4-All loads (Normal) 2.8 0.62 0.75 1.46B4- (Off peak) 2.8 0.49 0.75 1.09B4- (Peak) 2.8 1.25 0.75 1.80Bulk Supply Tariff
C-1 (a) 400 Volts 0.83 0.75 2.65C-1 (b) 400 Volts 2.2 0.68 0.75 2.64C-2 (a) 11/33 kV 0.69 0.75 2.51C-2 (b) POF WAH 0.95 0.75 2.87C-2 (c) Others 2.16 0.65 0.75 2.61C-2 (d) AJ & K 0.9 0.75 1.78C-3 66/132 kV 2.14 0.63 0.75 2.37Agricultural Tube-well Tariff-D1-SCARP 0.83 0.75 2.262- (1) Punjab & Sindh 0.82 0.49 0.75 0.762- (2) NWFP & Baluchistan, district Mainwall, Bahawalpur in Punjab & Tharparkar in Sindh
0.72 0.34 0.75 0.59
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1.3 Needs of CDM project
The field of the Energy Department produces "greenhouse gases." In fact, it discharges more than 80% of the total carbon dioxide emissions. Of the electric power generated by fossil fuels, 1 to 2 pounds (0.25-0.5kg) of carbon dioxide is produced according to estimates per kWh. That is the main greenhouse gas.
In order to keep the environment within the range of international standards, the Government of Pakistan has set up Environmental Protection Agencies on a national level and on a provincial level in 1995. The environmental laws set up by the Government of Pakistan have already been promulgated in order to monitor and control emissions according to the National Environmental Quality Standards (MEQSs). Table 1.3.1 shows the NEQSs in detail.
As stated in the foregoing paragraphs, Pakistan is suffering a chronic shortage of electric power and has not been able to respond to it because of its economic situations. In order to break the circumstances, it is the best way to raise fund by applying the CDM system and effect rehabilitation of the existing power stations.It is much considerable that Pakistan needs to apply the CDM system as a nation.
Table 1.3-1 National Environmental Quality Standard for Gaseous Emission
Parameter Source of EmissionExistingStandards
RevisedStandards
(mg/m3N) (mg/m3N)Nitrogen Nitric acid manufacturing unit 400 3,000Oxides Other plants except power plants operating on
oil or coal:Gas fired 400 400Oil fired - 600Coal fired - 1,200
Sulfur Sulfuric acid/Sulfunic acid plants 400 5,000Oxides Other plants except power plants operating on
oil or coal 400 1,700
Particulate a) Boilers & Furnaces:matter 1) Oil fired 300 300
2) Coal fired 500 5003) Cement kilns 200 300
b) Grinding, Crushing clinker coolers and related processes, metallurgical processes, converters, blast furnaces and cupolas
500 500
-1-11
2. Necessity of energy-saving technology in the proposed fields of business
The emissions of environmental pollutants are greatly affected by the quality of fuel. Petrol fuels currently imported by Pakistan State Oil (PSO) have a high content of sulfur (3.5%). Most of the thermal power plants do not conform to the NEQSs.
KESC uses a mobile monitoring system (an environmental measurement vehicle) to measure the levels of environmental pollutants in the atmosphere. However, the agency has only two such vehicles. Such measurements are taken only around the Bin Qasim Power Station (which is the largest power station that KESC has) and in the center of Karachi. No specific data is available concerning the gas turbine power plants surveyed in our present project.
However, as described in detail in Chapter 2, the gas turbines were put into operation more than two decades ago, with a decline in output and power generation efficiency. Such a decline in power generation efficiency results in extra fuel needed to obtain the same output. Rehabilitating the gas turbines is expected to save fuels, thus saving energy. It is therefore quite significant to introduce technology for energy saving.
As stated in this Chapter, of the fuels for power generation in Pakistan, it depends on imports from the neighboring countries for the fuel oil (HSDO), but its needs for natural gas is met by the domestic production. However, the import of fuel oil is restricted because of the nation’s rather poor foreign currency reserves, and the amount of natural gas produced within the nation has decreased. Under the circumstances, economy of fuels through the introduction of energy saving technologies has a great significance to the Pakistani Government and KESC
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3. Significance, needs, and effect of the project and the spread of the achievements to similar industries
In its 9th Five-Year Plan, the Government of Pakistan is planning to service the basic facilities conforming to the environmental criteria. The EPA is planning to introduce an environmental control system in order to control pollution at its source. The Government of Pakistan also encourages the use of clean fuels and takes the leadership in activities to convert petrol-fired power stations into natural-gas-fired ones.
In addition to the gas turbine power generation facilities that were covered in our present survey, Pakistan has many power plants which are more than ten years old and have declined in power generation efficiency. These can be rehabilitated and their power generation efficiency can be increased to save fuels, save energy, and reduce emissions of carbon dioxide.
This project is quite significant because it will improve the environment, together with fuel conversion from petrol to natural gas. Hopes also run high for the spread of such achievements to similar industries, because such a project is effective in power stations owned by IPPs which are likely to undergo similar problems in the future.
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Chapter 2 Materialization of the Project Plan
This chapter describes the project plan, gives an overview of the implementation site, and matters related to the funding proposal and the CDM. The overview of the implementation site describes the status of KESC and the implementation site based on the field survey and the post modified specifications and the contents of the system, instrumentation and arrangement in the technical aspects. The description of the funding proposal describes the way of KESC and Pakistan Government (the fund guarantor) considers the sources of funds and the prospects of fund procurement. The description of matters related to the CDM summarizes the way the Pakistan Government and KESC think of the matters.
1. Project plan
1.1 Overview of the regions to be covered in the project
As described in 1.2 of Chapter 1, KESC supplies electric power only to Karachi and its surroundings. The supply area covered is about 2,300 square miles (about 5,900 square kilometers).
Consumers in the power sale area of KESC number more than 1.36 million (as of June, 1999). However, this is the number of consumers who pay their electric power charges. The actual number of consumers is estimated to more than double that number. Karachi has an estimated population of 13 million as of 1999, and the population continues to grow at more than 5% a year. Despite some gaps between the rich and the poor, the citizens lead Western style lives. The market has a rich stock of materials, with widely-spread consumer electronics.
Karachi is Pakistan's only seafront city. Its portuary equipment is being developed and serviced to industrialize the city. The region containing the KORANGI and SITE gas turbine power plants (covered in our present survey) is an industrial zone. Factories are being built one after another at an eye-catching rate, including petrochemical, textile, automobile, and steel mills.
Due to a rise in the power consumption of ordinary consumers and factories, electric power is chronically in tight supply throughout the year. Except for the winter (December to February the next year), KESC imposes load-shedding on power supply in Karachi, except for the industrial zones. This program consists of dividing the urban area of Karachi into 12 blocks and suspending the power supply (outage) for 2 hours with time lags for each block. The time zones for outage are changed every other week and publicized in the newspapers. On Fridays, the entire area undergoes an outage from 12:00 to 14:00 because this time zone is for Muslim prayers. In addition, problems with the power transmission line often cause an outage. Citizens are
2-1
naturally strongly dissatisfied with these limits on power supply. Firms and affluenthouseholds counter these outages with diesel dynamos.
1.2 Contents of the project
The primary solution to the chronic power shortage of Karachi is to increase KESC's power supply capacity. However, KESC is subject to a freeze of construction plans for new power stations due to financial problems. As described in 1.2 of Chapter 1, therefore, the shortage of power is covered by purchasing electricity from WAP DA, IPPs and other corporations. However, these purchases make KESC even worse financially, resulting in a vicious circle.
Under these circumstances, the most effective measure to increase KESC's power supply capacity is to give the installed power plants additional power capacities.
Table 1.2.1 shows the installed power plants owned by KESC.
Table 1.2.1 Installed power plants owned by KESC
Stationname
Turbinetype
UnitNo.
CommerciaI operation
Maximum power generation (MW)Design 1999
BINQASIM
Steam 1 1983 210 1902 1984 210 1903 1989 210 904 1990 210 1405 1991 210 1506 1997 210 200
Total - 1,260 960KORANGI Steam 1 1966 66 25
2 1966 66 03 1970 125 904 1977 125 85
Total - 382 200KORANGI Gas 1-4 1979 100 70SITE Gas 1-5 1980 125 80
Total - 1,867 1,310
In every power station, most of the equipment is more than ten years old, with a considerable decline in output due to deterioration over the years. Their power generation efficiencies have also declined greatly, presumably by more than 5%. The decline in power generation efficiency means a rise in the consumption of fuels required for power generation. For example, in the case of gas-fired power plants which had a power generation efficiency of 28% when put into operation, they need 22% more fuel to obtain the same output when their power generation efficiency has declined 5%. In the case of natural gas, the fuel has a carbon content of 75%, so that it discharges 16% more carbon dioxide.
-2-2
KORANGI and SITE gas turbine power plants (which were covered in our present survey) are located in an industrial zone and play a important role as a source of power for the households and factories around them. Carrying out a survey project for the gas turbines of both power stations and leading the survey to the future rehabilitation of the gas turbines will increase the output and power generation efficiency of the power stations. This will not only save fuels, save energy, and improve KESC financially, but also meet the objectives of the COM (that is, reducing carbon dioxide emissions).
This research aims at the reduction of the consumption of fuels through energy saving and emission of C02 by replacing gas turbines and auxiliary equipment of the both power stations with latest models and raise their power generation efficiency.
1.3 Targeted greenhouse gases and other matters
Since the gas turbine power plants are fueled mainly by natural gas, the targeted greenhouse gas will be carbon dioxide. As shown in Table 1.2.1, the gas turbine power plants are more than twenty years old. Previous regular inspections indicate a decline in the power generation efficiency of the gas turbines, so that the present survey is projected to result in a considerable reducing effect of carbon dioxide. The findings will be described in detail in Chapter 3.
2-3
2. Outline of the implementation site (corporation)
2.1 Interest level at the implementation site (corporation)
As described in clause 1.2, in order to modify the electric power situation of Karachi city, KESC wishes very strongly to realize the gas turbine replacement project. However, in view of the previous maintenance conducted whenever possible on the gas turbine, KESC intends to reuse as many of the usable parts as possible. According to this concept, below two cases concerning the specifications for related equipment are set up after modification.
(1) Case 1
Each gas turbine and generator will be replaced as the latest ones
(2) Case 2
Gas turbine will be replaced. Generator will be reused after rewinding its stator coil.
Details of these cases are described in clause 2.4.
Regarding the interest in the CDM, which is described in 1.2, KESC knows regarding its concrete methods and other matters, no clear-cut approach has been indicated.
KESC is much interested in this replacement project, and wishes strongly to apply Yen Credit, particularly the Special Environment Yen Credit in order to realize this project.
2-4-
2.2 Equipment and facilities condition of the implementation site(outline, specification and operation condition)
2.2.1 KORANGI GT PS
(1) Site overview
This power station is located in the industrial zone about 15 km east of Karachi city. Four gas turbine power generating facilities of model PG-5341 and having an output of 19,500kW (temperature : 40 °C): along with accompanying equipment. These facilities were started commercial operation in 1978.
This power station is located in a dry climate area and more than 5 km from the nearest water source (river). A plan has been considered to modify the station into a combined-cycle plant but has never been implemented because water supply for steam and cooling water is hard.
Operating time and numbers of start and shutdown of each unit to October 2000 are shown below.
Unit 1 : 80,516h, 5,200 times
Unit 2 : 71,974h, 5,668 times
Unit 3 : 69,943h, 5,673 times
Unit 4 : 69,900h, 5,435 times
Since the fuel price becomes higher, these facilities are only operated during the peak hours between 18:00 and 24:00. The equipment can be operated on both natural gas and HSDO. But the plants are operated by natural gas (which is cheaper) at 95 % and by HSDO at the remaining 5 % on a power consumption basis.
The equipment is generally maintained in a good condition. However, it has been operating for 22 years and has undergone longer overhaul intervals of virtually 7 to 8 years (which represents an interval of 24,000 operating hours as recommended, but the plants are only operated during the peak hours). This interval is longer than the standard in Japan, which is 2 to 3 years, resulting in a decline in the power generator output and efficiency.
Some remarks concerning the deterioration of the gas turbine auxiliary equipment are shown below.
1) A rise in filter cleaning frequency due to a dirty inlet air filter.
2-5
2) Poor instructions about the gas flow meter make it difficult to evaluate the unit price of power generation inside this power station.
3) A decline in output that is considered to be due to the efficiency deterioration of the gas turbine compressor.
It is difficult to supply cooling water and to control water quality for the lubrication oil cooling system using the cooling tower type. Power plant member wishes to replace the equipment with a radiator type, which contains a closed loop of cooling water and with which water quality is easier to control.
The results of a field survey and hearing concerning this power station are shown in Table 2.2-1 to 2.2-11.
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Table 2.2-1 Summary of Inspection Results (1)
KORANGI GT PS Unit No.1 (GT-185) Unit No.2 (GT-186) | Unit No.3 (GT-187) Unit No.4 (GT-188)
No. Inspection Item Inspection Results
1 Unit operating condition(1) Operating Starts (times) 5,200 5,668 5,673 5,435(2) Operating h (h) 80,516 71,974 69,943 69,900(3) Operating Load (MW) 18—19 18-19 17 17(4) Exhaust Temperature(°C) 485 499 510 492(5) Operation Mode Base Load Operation Base Load Operation Base Load Operation Base Load Operation
(6) Fuel TypeNatural Gas (HSDO for emergency)
Natural Gas (HSDO for emergency)
Natural Gas (HSDO for emergency)
Natural Gas (HSDO for emergency)
2 Maintenance History 1.Major overhoulings were carried out every 24,000 h. (Total 3 times)
1.Major overhoulings were carried out every 24,000 h. (Total 3 times)
1.Major overhoulings were carried out every 24,000 h. (Total 3 times)
1.Major overhoulings were carried out every 24,000 h. (Total 3 times)
3 Damaged Parts & Equipments
1 Gas flow meter LGas flow meter2. Turbine Shell Casing3. Air Cleaner Inertial
Separator of Inlet House
1 .Gas flow meter 1 .Gas flow meter
4 Isolation1) Gas Purge2) Isolation Plate
Not Applicable Not Applicable Not Applicable Not Applicable
2-8
Table 2.2-2 Summary of Inspection Results (2)KORANGIGT PS Unit No.1 (GT-185) | Unit No.2 (GT-186) I Unit No.3 (GT-187) Unit No.4 (GT-188)
No. Inspection Item Inspection Method Inspection Results5 Inlet House
1) Filter Visual Inspection re-usedrecommend using self cleaning type filter
re-usedrecommend using self cleaning type filter
re-usedrecommend using self cleaning type filter
re-usedrecommend using self cleaning type filter
2) Blowing Door Visual InspectionCheck operating condition
Should be checked. Should be checked. Should be checked. Should be checked.
3) Inlet House Inside Visual Inspection re-used re-used re-used re-used6 Enclosure Duct
1) Turbine Room Duct Visual Inspection re-used re-used re-used re-used2) Reduction Room
DuctVisual Inspection re-used re-used re-used re-used
7 Circulation Fan1) Bearing Lube Oil Check lube oil amounts Should be checked. Should be checked. Should be checked. Should be checked.2) Check Fan Surface Visual inspection Should be checked. Should be checked. Should be checked. Should be checked.
8 Inlet Duct1) Inspect Duct inside Visual inspection Should be checked. Should be checked. Should be checked. Should be checked.
9 Inlet Plenum1) Inspect Plenum inside Visual inspection Should be checked. Should be checked. Should be checked. Should be checked.
10 Exhaust Plenum1) Inspect Duct inside Visual inspection Should be checked. Should be checked. Should be checked. Should be checked.2) Exh. Thermo-couple
11 Exhaust Duct1) Expansion Joint Visual inspection Should be checked. Should be checked. Should be checked. Should be checked.2) Inspect Duct inside3) Check Foundation
Bolts
Table 2.2-3 Summary of Inspection Results (3)KORANGI GT PS Unit No.1 (GT-185) I Unit No.2 (GT-186) Unit No.3 (GT—187) Unit No.4 (GT-188)
No. Inspection Item Inspection Method Inspection Results12 Casing
1) Compressor Inlet Casing
Visual inspection Should be checked. Should be checked. Should be checked. Should be checked.
2) CompressorMiddle, Discharge Casing
Visual inspection Should be checked. Should be checked. Should be checked. Should be checked.
3) Turbine Shell Casinga) 1 st Stage Shroud Visual inspection Should be checked.
If necessary replaced by new ones.
Should be checked.If necessaryReplaced by new ones.
Should be checked.If necessaryReplaced by new ones.
Should be checked.If necessaryReplaced by new ones.
b) 2 nd Stage Shroud Visual inspection Should be checked.If necessary replaced by new ones.
Should be checked.If necessary replaced by new ones.
Should be checked.If necessary replaced by new ones.
Should be checked.If necessary replaced by new ones.
c) Plug for Bore Scope Visual inspection Should be checked. Should be checked. Should be checked. Should be checked.
d) Exhaust Hood Visual inspectionPT inspection
Should be checked.If necessary replaced by new ones.
Should be checked.If necessary replaced by new ones.
Should be checked.If necessary replaced by new ones.
Should be checked.If necessary replaced by new ones.
e) Exhaust Drum Visual inspection Should be checked. Replaced by new one if necessary.
Should be checked. Replaced by new one if necessary.
Should be checked. Replaced by new one if necessary.
Should be checked. Replaced by new one if necessary.
2-10
Table 2.2-4 Summary of Inspection Results (4)KORANGI GT PS Unit No.1 (GT-185) Unit No.2 (GT-186) | Unit No.3 (GT-187) Unit No.4 (GT-188)
No. Inspection Item Inspection Method Inspection Results13 Combustor
1) Fuel Nozzle Visual inspectionPT inspection
Should be checked.If necessary replaced by new ones.
Should be checked.If necessary replaced by new ones.
Should be checked.If necessary replaced by new ones.
Should be checked.If necessary replaced by new ones.
2) Combustion Chamber Visual inspectionPT inspection
Should be checked. Should be checked. Should be checked. Should be checked.
3) Combustion Liner Visual inspectionPT inspection Clearance Check
Should be checked.If necessary replaced by new ones.
Should be checked.If necessary replaced by new ones.
Should be checked.If necessary replaced by new ones.
Should be checked.If necessary replaced by new ones.
4) Transition Piece Visual inspectionPT inspection
Side Seal Plate Wear condition Check
Clearance Check
Should be checked.If necessary replaced by new ones.
Should be checked.If necessary replaced by new ones.
Should be checked.If necessary replaced by new ones.
Should be checked.If necessary replaced by new ones.
5) Cross Fire Tube Visual inspection Should be checked.If necessary replaced by new ones.
Should be checked.If necessary replaced by new ones.
Should be checked.If necessary replaced by new ones.
Should be checked.If necessary replaced by new ones.
6) Retainer Visual inspection Should be checked.If necessary replaced by new ones.
Should be checked.If necessary replaced by new ones.
Should be checked.If necessary replaced by new ones.
Should be checked.If necessary replaced by new ones.
Table 2.2-5 Summary of Inspection Results (5)KORANGI GT PS Unit No.1 (GT-185) Unit No.2 (GT-186) | Unit No.3 (GT-187) Unit No.4 (GT-188)
No. Inspection Item Inspection Method Inspection Results14 Rotor, Nozzle
1) Rotor Visual inspection Balancing weight check PT inspection for journal port
From the point of parts life should be inspected at qualified factory.
From the point of parts life should be inspected at qualified factory.
From the point of parts life should be inspected at qualified factory.
From the point of parts life should be inspected at qualified factory.
2) Compressor Blade Visual inspectionPT inspection
From the point of parts life should be inspected at qualified factory.
From the point of parts life should be inspected at qualified factory.
From the point of parts life should be inspected at qualified factory.
From the point of parts life should be inspected at qualified factory.
3) Turbine 1st Bucket Visual inspectionPT inspection
From the point of parts life should be inspected at qualified factory.
From the point of parts life should be inspected at qualified factory.
From the point of parts life should be inspected at qualified factory.
From the point of parts life should be inspected at qualified factory.
4) Turbine 2nd Bucket Visual inspectionPT inspection
From the point of parts life should be inspected at qualified factory.
From the point of parts life should be inspected at qualified factory.
From the point of parts life should be inspected at qualified factory.
From the point of parts life should be inspected at qualified factory.
5) Turbine 1st Nozzle Visual inspectionPT inspection
From the point of parts life should be inspected at qualified factory.
From the point of parts life should be inspected at qualified factory.
From the point of parts life should be inspected at qualified factory.
From the point of parts life should be inspected at qualified factory.
6) Turbine 2nd Nozzle Visual inspectionPT inspection
From the point of parts life should be inspected at qualified factory.
From the point of parts life should be inspected at qualified factory.
From the point of parts life should be inspected at qualified factory.
From the point of parts life should be inspected at qualified factory.
7) Inlet Guide Vane Visual inspectionPT inspectionBush Clearance Check Back rush CheckLVDT rod CheckLimit Switch Check
Should be checked. Should be checked. Should be checked. Should be checked.
z\-\
Table 2.2-6 Summary of Inspection Results (6)KORANGIGT PS Unit No.1 (GT-185) | Unit No.2 (GT-186) | Unit No.3 (GT-187) Unit No.4 (GT-188)
No. Inspection Item Inspection Method Inspection Results15 Bearing
1) No.1, No.2 Bearing Metal
Visual inspectionPT inspection
Should be checked.And replaced by new one if necessary
Should be checked.And replaced by new one if necessary
Should be checked.And replaced by new one if necessary
Should be checked.And replaced by new one if necessary
2) Thrust Bearing Metal Visual inspectionPT inspection
Should be checked.And replaced by new one if necessary
Should be checked.And replaced by new one if necessary
Should be checked.And replaced by new one if necessary
Should be checked.And replaced by new one if necessary
3) Bearing Housing Visual inspectionPT inspection
Should be checked. Should be checked. Should be checked. Should be checked.
16 Turbine Overhaul Work1) Jacking up Jacking up Casing Not applicable. Not applicable. Not applicable. Not applicable.
2) Clearance Check Clearance Check Should be checked during major overhaul.
Should be checked during major overhaul.
Should be checked during major overhaul.
Should be checked during major overhaul.
3) Rotational Check Rotor Position Check Not applicable. Not applicable. Not applicable. Not applicable.
4) Alignment (ACC-TB,TB~ Reduction Gear)
Alignment Check Adjustment
of Alignment
Should be checked during major overhaul.
Should be checked during major overhaul.
Should be checked during major overhaul.
Should be checked during major overhaul.
17 ACC Gear1) ACC Gear Visual inspection
Gear Teeth surface check
Over speed Trip Divide Check
Should be checked. Should be checked. Should be checked. Should be checked.
Table 2.2-7 Summary of Inspection Results (7)KORANGI GT PS Unit No.1 (GT-185) I Unit No.2 (GT-186) Unit No.3 (GT-187) Unit No.4 (GT-188)
No. Inspection Item Inspection Method Inspection Results18 Starting Device
1) Torque Converter Operation condition check Should be checked. Should be checked. Should be checked. Should be checked.
2) Solenoid Valve (20TU)
Operation condition check Should be checked. Should be checked. Should be checked. Should be checked.
3) Lube Oil Pump for Torque Converter
Operation condition check Should be checked. Should be checked. Should be checked. Should be checked.
4) Starting Motor Visual inspectionOperation condition check
Not applicable. Not applicable. Should be checked. Should be checked.
5) Starting Diesel Visual inspectionOperation condition check
Should be checked. Should be checked. Not applicable. Not applicable.
6) Starting Clutch Visual inspectionOperation condition check
Should be checked. Should be checked. Should be checked. Should be checked.
19 Ratcheting Device1) Ratcheting Oil Pump Visual inspection
Operation condition checkShould be checked. Should be checked. Should be checked. Should be checked.
2) Line Filter Visual inspectionElement change if necessary
Should be checked. Should be checked. Should be checked. Should be checked.
3) Ratcheting System Visual inspectionOperation condition check
Should be checked. Should be checked. Should be checked. Should be checked.
20 Lubricant Oil System1) Lube Oil Filter
_____
Visual inspectionElement change if necessary O-ring Change if necessary
______
Should be replaced by new one
Should be replaced by new one
___________________
Should be replaced by new one
Should be replaced by new one
2-14
Table 2.2-8 Summary of Inspection Results (8)KORANGI GT PS Unit No.1 (GT-185) | Unit No.2 (GT-186) Unit No.3 (GT-187) Unit No.4 (GT-188)
No. Inspection Item Inspection Method Inspection Results2) Oil Trip Line Filter Visual inspection
Element change if necessary Gasket change
Should be replaced by new one once per 3 years.
Should be replaced by new one once per 3 years.
Should be replaced by new one once per 3 years.
Should be replaced by new one once per 3 years.
3) Coupling Oil Filter Visual inspectionElement change if necessary Gasket change
Should be replaced by new one once per 3 years.
Should be replaced by new one once per 3 years.
Should be replaced by new one once per 3 years.
Should be replaced by new one once per 3 years.
4) Mist Separator Visual inspectionElement change if necessary Gasket change
Not applicable. Not applicable. Not applicable. Not applicable.
5) Mist Separator Fan Visual inspection Not applicable. Not applicable. Not applicable. Not applicable.
6) Lube Oil Cooler Visual inspectionPacking change if necessary Leakage check
Should be cleaned once per year.
Should be cleanedonce per year.
Should be cleanedonce per year.
Should be cleanedonce per year.
7) Main Lube Oil Pump Visual inspectionPT inspectionCoupling visual inspection
Should be checked. Should be checked. Should be checked. Should be checked.
8) Aux. Lube Oil Pump Operation condition check Should be checked. Should be checked. Should be checked. Should be checked.
9) Emergency Lube Oil Pump
Operation condition check Should be checked. Should be checked. Should be checked. Should be checked.
10) Pressure Regulator (VPR-1)
Operation condition check Should be checked. Should be checked. Should be checked. Should be checked.
11) Pressure Regulator (VPR-2)
Operation condition check Should be checked. Should be checked. Should be checked. Should be checked.
12) Lube Oil Tank Visual inspection Should be checked. Should be checked. Should be checked. Should be checked.
Table 2.2-9 Summary of Inspection Results (9)KORANGIGTPS Unit No.1 (GT-185) I Unit No.2 (GT-186) Unit No.3 (GT-187) Unit No.4 (GT-188)
No. Inspection Item Inspection Method Inspection Results21 Control Oil System
1) Control Oil Filter Visual inspectionElement change if necessary
Should be checked. Should be checked. Should be checked. Should be checked.
2) Control Oil Strainer Visual inspectionElement Cleaning
Should be checked. Should be checked. Should be checked. Should be checked.
3) Main Control Oil Pump Replaced by new oneInspect the quill shaft by PT
Should be checked. Should be checked. Should be checked. Should be checked.
4) Aux. Control Oil Pump Operation condition check Should be checked. Should be checked. Should be checked. Should be checked.
5) Accumulator Gas Pressure Check spec; 63kg/cm2
Should be checked. Should be checked. Should be checked. Should be checked.
6) Solenoid Valve (20FG-A)
Operation condition check Not applicable. Not applicable. Not applicable. Not applicable.
7) Solenoid Valve (20FG-A)
Operation condition check Not applicable. Not applicable. Not applicable. Not applicable.
22 Cooling and SealingAir System
1) 6 stage ExtractionValve
Operation condition check Should be checked. Should be checked. Should be checked. Should be checked.
2) 11 Stage ExtractionValve
Operation condition check Should be checked. Should be checked. Should be checked. Should be checked.
3) Orifice Size Visual inspectionCompressor Side:2 pcs Turbine Side:4 pcs Compressor Discharge Line
Should be checked during major overhaul.
Should be checked during major overhaul.
Should be checked during major overhaul.
Should be checked during major overhaul.
23 Cooling Water System1) Temperature Control
Valve (VTR-1)
Operation condition check Should be checked andIf necessary replaced by new ones.
Should be checked andIf necessary replaced by new ones.
Should be checked andIf necessary replaced by new ones.
Should be checked andIf necessary replaced by new ones.
2) Turbine supportWater jacket
Visual inspection Not applicable. Not applicable. Not applicable. Not applicable.
3) Cooling Pipes !Visual inspection Should be cleaned during major overhaul
Should be cleaned during !major overhaul.
Should be cleaned during major overhaul.
Should be cleaned during major overhaul.
9I-Z
Table 2.2-10 Summary of Inspection Results (10)KORANGI GT PS Unit No.1 (GT-185) | Unit No.2 (GT-186) | Unit No.3 (GT—187) Unit No.4 (GT-188)
No. Inspection Item Inspection Method Inspectio n Results24 Gas System
1) Gas Strainer Visual inspection Should be cleaned periodical Should be cleaned periodical Should be cleaned periodical Should be cleaned periodical
2) SRV/GCV Visual inspectionGasket change if necessary LVDT visual inspection Leakage checkOperation condition check
Should be checked. Should be checked. Should be checked. Should be checked.
3) Gas flow meter Visual inspection & hearing
Should be replaced bynew one.
Should be replaced by new one.
Should be replaced bynew one.
Should be replaced bynew one.
25 Fuel Oil System1) Main fuel pump2) HP filter3) By-pass control valve4) Fuel stop valve5) Flow meter
Visual inspectionCheck differential pressure Visual inspection
Should be checked. Should be checked. Should be checked. Should be checked.
26 Atomizing air system1) Atomizing compressor2) Pre-cooler3) After-cooler4) Air separator5) Air filter6) Booster compressor
Visual inspectionVisual inspection
Check differential pressure Check differential pressure
Should be checked. Should be checked. Should be checked. Should be checked.
27 Piping1) Cooling and Sealing
Air PipeVisual inspection Should be cleaned during
major overhaul.Should be cleaned during major overhaul.
Should be cleaned during major overhaul.
Should be cleaned during major overhaul.
2) Exhaust FlameCooling Air Pipe
Visual inspection Not applicable. Not applicable. Not applicable. Not applicable.
3) Gas Pipe Visual inspection Should be cleaned during major overhaul.
Should be cleaned during major overhaul.
Should be cleaned during major overhaul.
Should be cleaned during major overhaul.
4) Leakage Check Should be checked during major overhaul.
Should be checked during major overhaul.
Should be checked during major overhaul.
Should be checked during major overhaul.
2-17
Table 2.2-11 Summary of Inspection Results (11)KORANGI GT PS Unit No.1 (GT-185) | Unit No.2 (GT-186) | Unit No.3 (GT-187) Unit No.4 (GT-188)
No. Inspection Item Inspection Method Inspection Results28 Instrument
1) Servo Valve90SR, 90TV, 65GC
Lift Calibration CheckVisual inspection
Should be Replacedd by new one from the point of parts life.
Should be Replacedd by new one from the point of parts life.
Should be Replacedd by new one from the point of parts life.
Should be Replacedd by new one from the point of parts life.
2) Speed Sensor77NH-1,2,3
Gap checkVisual inspection
Should be checked during major overhaul.
Should be checked during major overhaul.
Should be checked during major overhaul.
Should be checked during major overhaul.
3) Transformer (LVDT)
Lift Calibration Check Should be checked during major overhaul
Should be checked during major overhaul
Should be checked during major overhaul
Should be checked during major overhaul
4) Flame Detector (28FD)
Operation condition check Replaced spare if necessary
Should be checked periodically.
Should be checked periodically.
Should be checked periodically.
Should be checked periodically.
5) Spark Plugand Transformer
Operation condition check Should be checked periodically.
Should be checked periodically.
Should be checked periodically.
Should be checked periodically.
6) Vibration Sensor Characteristic check Should be calibrated periodically.
Should be calibrated periodically.
Should be calibrated periodically.
Should be calibrated periodically.
7) Axial Vibration Sensor Characteristic check Not applicable. Not applicable. Not applicable. Not applicable.
8) ExhaustThermocouples
Characteristic check Should be checked periodically.
Should be checked periodically.
Should be checked periodically.
Should be checked periodically.
9) Wheelspace Thermocouples
Characteristic check Should be checked periodically.
Should be checked periodically.
Should be checked periodically.
Should be checked periodically.
10) Lube OilThermocouples
Characteristic check Should be checked periodically.
Should be checked periodically.
Should be checked periodically.
Should be checked periodically.
29 C02 Fire Fighting System1) C02 Gas Pressure Visual inspection Should be checked
periodically.Should be checked periodically.
Should be checked periodically.
Should be checked periodically.
2) C02 Control Panel Operation condition check Should be checked
periodically.
Should be checked
periodically.Should be checked
periodically.
Should be checked
periodically.
30 Isolation1) N2 purge
Gas engagedNot applicable. Not applicable. Not applicable. Not applicable.
(2) Status of the equipment
1) Existing F5 gas turbine equipment
An overview of the power station is shown in Fig.2.2-1. The specifications of the major equipment are shown in Table 2.2-12. As shown in Fig. 2.2-2 and 2.2-3, the package appearance of the gas turbine equipment and the premises are serviced comparatively well. The gas turbine casing and the equipment surrounding the combustor are also serviced as shown in Fig. 2.2-4 to 6.However, according to the results of the latest major overhauling inspection, the casing contains some cracks, which leads to suspect some secular deterioration.
The internal condition of the auxiliary equipment for the gas turbine is shown in Fig. 2.2-7 to 2.2-9. It shows no non-conformances that cause functional problems, thus demonstrating that the equipment is appropriately maintained.
2) Inlet air filter
The east neighbour of this power station is an IPP diesel power station (its output is 126MW).The stack of the thermal power plant discharges brown diesel smoke (Fig. 2.2-10). This smoke sticks to the air filter of the gas turbine in this power station. The filter is therefore cleaned frequently (Fig. 2.2-11). Fig. 2.2-12 shows how the filter on the outside of the air suction chamber is removed for cleaning. Fig. 2.2-13 and 2.2-14 indicate the condition inside the inlet house. Every time it becomes dirty, the filter is water-washed. These problems have presumably come to the surface because this power station is located in a dry climate area and the air filter is in a condition that easily makes it dirty and because power stations, factories, and other equipment were added on in the surroundings. The equipment can be modified into a self-cleaning air filter to reduce the frequency of cleaning and to delay the decline in power generator output and efficiency.
2-18-
Table 2.2-12 Specification of Major Mechanical Equipment
1. Gas Turbine
Manufacturer Hitachi, Ltd.
Type Open-Cycle, Single-Shaft, Industrial Type Gas Turbine
Model Hitachi PG—5341
Compressor Type Axial Flow Type
Number of Stages 17 Stages
Combustor Type Cannular TypeNumber of Quantities 10 Cans
Turbine Type Axial Flow, 1st Stage; Impulse and 2nd Stage; Reaction Type
Number of Quantities 2 Stages
Shaft Speed 5,100 rpm
Direction of Rotation Clockwise viewed from output coupling
Over speed Trip Setting Electrical Over Speed; 5, 610±30 rpm (109.41 -—-110.59%) Mechanical Over Speed; 5,738±50 rpm (111.53^113.49%)
Gas Turbine Rotor Weight Approx. 9 Tons
2. Reduction Gear
Manufacture Hitachi, Ltd.
Type Quill Shaft - DoubIe Helical Gear
Gear Speed Turbine Side; 5,100 rpm, Generator Side; 3,000 rpm
3. Turning Equipment
Turning Speed Approx. 1~2 revolution/hr
Turning Method Hydraulic Ratcheting System
Norma I Turning Period after Operation at Base Load
Approx. 24 hours
4. Starting Equipment
Type of Starter Diesel Engine (for No. 1, No.2) / Motor (for No.3, No.4)
Capacity 500 HP / 400 HP
Starting Time to Full Load Normal; 11 min. Fast: 7 min. 30 sec.
5. Exhaust System
Type of Silencer Parallel Baffle Type, 10 ft
Material of Sound Absorber Rock Wool
Maximum Pressure Loss 20 mmAq
Material of Expansion Joints Stainless Steel and Teflon Cloth
-2-19
6. Inlet Air FiIter
(1) 1st Stage Filter Type Inertial Separation Type
(2) Bleed Fan
Type Radial Fan
Quantity 2 per Unit
Capacity 290 mVmin.
Static Pressure 90 mmAq (at 40°C)
(3) Motor
Capacity 11 kW
Number of Pole 4
Voltage AC 400 V
Frequency 50 Hz
Insulation Type B
(4) Second Stage Filter
Type Bag Type (Washable Type)
Media Material Polyester Fiber
Quantity Full Size: 80 pcs, Half Size: 16 pcs.
Capacity 5,800 mVmin.
Pressure Drop Initial: 13.6 rrniAq, Final: 20 mmAq.
(5) Emergency Dumper
Quantity 1 set
Cracking Pressure 75 mmAq (Vacuum)
2-20
3) Auxiliary equipment
® Turbine monitoring instruments
It is desirable to make the corrections described below for some of the important monitoring instruments for protecting and controlling the gas turbine.
- Exhaust gas temperature detection thermocouple (total 18 per one unit used for protection and control) wires are cut down of three in Unit 1, one in Unit 2, seven in Unit 3, and nine in Unit 4. It is desirable to provide the spare parts and replace the damaged devices soon.
- One wheel space temperature detection thermocouple (total 8 per unit used for protection) wire is cut down in Unit 1 and Unit 2. They should desirably be replaced soon.
- One similar thermocouple (total 8 per one unit) detection value is a little higher than normal state in Unit 3 and in Unit 4. They should also desirably be calibrated and replaced whenever necessary.
(D Cooling water system
The cooling water system of this power station incorporates a gas cooler (Fig. 2.2-15). The gas turbine lubrication oil is therefore smoothly cooled and now in a good operating state. In the topographical situation of the site, however, an open cooling water system is expected to undergo technical and financial difficulties because of the need to secure water and control water quality, from a long-term outlook. The equipment should desirably be changed to a closed system.
4) Hot gas path parts
Two sets of first-stage nozzles are put at the workshop of this power station. They were scrapped because they had been out of repair limit (Fig.2.2-16 and 2.2-17). They were highly damaged so that no appropriate measure was taken even though an overhaul was conducted. When an overhaul is conducted, appropriate measures should desirably be taken according to the repair standards. To that end, one of the prerequisite is to secure hot gas path parts as spare parts.
-2-27-
5) Fuel supply system
a) Gas compressor
This gas compressor has been operating since 1979 to supply natural gas for the existing F5 gas turbine. One gas compressor supplies gas each gas turbine. A total of four units are installed.
No. 1 - serial number: 76A1101501, model: 1100kW, BTD-ICC
No. 2 - serial number 76A1101502, model: 1100kW, BTD-ICC
No. 3 - serial number 76A1101601, model: 1100kW, BTD-ICC
No. 4 - serial number: 76A1101602, model: 1100kW, BTD-ICC
The existing gas compressor specifications are shown in Table 2.2-13, and a flow sheet is shown in Fig. 2.2-18. Fig. 2.2-19 shows the number of gas turbines that can be operated due to the change in the suction pressure of existing gas compressors. When suction pressure is 60 psig or less, one unit of gas turbine is operated for one unit of gas compressor. There is no standby unit.
Table 2.2-14 shows the total operating time of the existing gas compressors from the start-up of their operation to October 17, 2000.
Table 2.2-14 Operating time of the gas compressors
No.1 No.2 No.3 No.4
Total operating time (h) 38,872 23,731 30,593 28,733
Gas compressors are overhauled every 8,000 hours in Japan, but no major overhaul has been conducted in this plant except for partial replacements such as those of cylinder valves.
Due to the power demand in Karachi city, these gas compressors are stopped during the daytime. During this survey, therefore, inspection of the compressors’ condition could, not be conducted in the operation mode. The operation status based on an appearance inspection of the stopped gas compressors and the log sheets obtained from this power station are reported. All of four gas compressors were operable.
-2-30-
Table 2.2-13 Original specification for the gas compressor (KORANGI GT PS)
Item Unit Data
Number of units — 4
Type — BTD-ICC
Serial number —76A1101501, 2
76A1101601, 2
1st stage suction pressure psig 30-150
2nd stage discharge pressure psig 230
Gas capacity kg/h7,50Q(at 30Psig)
30,000(at 150Psig)
Suction temperature °C 15-45
Gas component
mol %
ch4 94.42
X(S' 1.05
CgHg 0.28
C4H10 0.12
C5H12 0.05
n2 389
0 p 0.02
02 0.17
Molar Weight — 16.85
Cylinder lubrication — Yes
Cylinder diameter x unit 1st stage (mm) 0615X1
2nd stage (mm) 0466X1
Piston rod diameter mm 090
Stroke mm 315
Speed min1 369
Driver type — Induction motor
Output power of main motor kW 1,100
2-31
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NO. REVISIONS j DATE REVISED CHECKED
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EOHSULTA/JTS : R/CHTAJER CPUS ULTIMO ERE ipEB RSTHIS DRAWING IS THE PROPERTY OF HITACHI. THE OATA. INFORMATION OR ANY PART OF THE DRAWING HEREON SHALL NOT BE COPIED. REPRODUCED. LOANED OR USED FOR ANY PURPOSE WITHOUT WRITTEN PERMISSION FROM HITACHI.
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Fig. 2.2-18 Flow Diagram of Existing Gas Compressor
(D Appearance of the gas compressors
(1) Gas compressors proper
1) Unit 3
An oil leak was found in the check valve for oiling the second cylinder. It needs to be replaced with a new one (Fig. 2.2-20).
2) Unit 4
A trace of a gas leak was found in the discharge pipe and the discharge snubber of the second cylinder. They must be overhauled, and reassembled (Fig. 2.2-21).
An oil leak was found in the mating face between the frame and cross guide. It is necessary for overhauling, replacing gaskets and reassembling (Fig. 2.2-22).
(2) Lubricator for internal oil
Some elements function poorly. They must be replaced with new ones (Fig. 2.2-23).
(3) Capacity control valve
It is aged but is generally trouble-free now (Fig. 2.2-24).
(D Gas compressor suction line (Fig. 2.2-25)StationSnubber
<S>—O—O<E>—CD—CDComp a aj
Suction
GasTurbina
Fig. 2.2-25 Flow Chart of Gas Compressor Suction Line
(D Natural gas supplied to the gas compressor
(1) Gas composition
Name Vol%
Methane (CH4) 94.36
Ethane (C2H6) 0.96
Propane (C3H8) 0.28
Butane (C4H10) 0.15
Hydrogen (H2) 0.25
Nitrogen (N2) 4.10
Carbon dioxide (C02) 0.66
® Representative log sheet of the gas compressor
Table 2.2-15 shows the ranges of each item in the log sheet obtained as representative data from this power station.
Table 2.2-15 Log sheet of the gas compressor (KORANGIGT PS)
Item Units Data
Suction pressure P, point A* psig 77 to 127
Discharge pressure psig 230 to 238
Suction temperature T, point A* °C No data
Discharge temperature First stageSecond stageAfter the after-cooler
°F
CO)
92 to 116 (33.3 to 46.7)
108 to 142 (42.2 to 61.1)
80 to 122 (26.7 to 50.0)
Cooling water supply temperature°F
CO)87 to 100 (30.6 to 37.7)
Cooling water outlet temperatureOil coolerInter-cooler
After-cooler
°F
CO)
85 to 101 (29.4 to 38.3)
101 to 124 (38.3 to 51.1)
100 to 114 (37.8 to 45.6)
Current of main motor A 195 to 280
*: Represents point A in the flowchart of the suction line in Fig. 2.2-25.
-2-38
As supplementary information for Table 2.2-15, some information were obtained about the previous trends in the matters mentioned below that affect the performance of the gas compressor, by a hearing with this power station staff.
Suction pressure: P, point A*, 50 to 140 psig (90 to 100 psig average)
Suction temperature: T, point A*, 85°F average
b) Fuel supply equipment
Total power generation of this power station depends on natural gas for 95% and on HSDO for 5%. As indicated in Figs. 2.2-26 and 2.2-27, the system is provided with a fuel oil heater (for light diesel oil) but it is now not used.
c) Gas flow meter
For the gas flow meter (Fig. 2.2-28), all of them on the four gas turbines have long been in non-working condition. Based on the result of this hearing, it was estimated that this was due to a breakdown of the calculating unit (Fig. 2.2-29). However, the pressure transmitter (Fig. 2.2-30) has long been provided with no calibration or other adjustment, so that it has declined in instrument reliability. The replacement of the gas flow meter is imperative if one wishes to monitor the time-series changes such as dirt in the air compressor, thus operating the gas turbine equipment soundly and economically.
-2-39-
6) Electrical system
The specifications of the major electrical equipment are as follows:
Substation bus GeneratorNeutral grounding transformer Neutral grounding resister (NGR)Generator circuit breaker Set-up transformer Main auxiliary transformer External transformer DC equipmentCommon auxiliary transformer
132kV27,687kVA (at 27°C), 11500V, 50Hz, 0.8PF 10kVA, 12kV/240V 1.080, 205A, 1min
MBB, 13.8kV, 2000A, 500MVA
22/30MVA, 132kV±2x2.5% 120kVA(ONAN), 11500V, 420V-380V-360V 230kVA200Ah/20h (Lead acid type)2sets, 5MVA, 11.5kV±2.5%, 3.45kV
There has been no change in electrical specifications from the original except for the replacement of the high-pressure bushing on the main transformer in Unit 1. Electrical equipment including substation are operated without any trouble.
-2-42-
7) Generator
The basic specifications of the generator are as follows:
Model: Open draft type, 3-phase synchronized generator
Capacity: 27,687 kVA (at an atmospheric temperature of 26.7°C (= 80°F))
Quantity: 4 units
Installed location: Outdoors
Rated power factor: 0.8
Rated output: 22,150 kW
Frequency: 50 Hz
Rated engine speed: 3,000 rpm
Rated voltage: 11,500 V
Number of phases: 3 phases
Short-circuit ratio: over 0.49
Insulation type: Type F (J EC-114)
Excitation voltage: 300 V
Neutral grounding system: Neutral point transformer
Turning direction: Clockwise as viewed from turbine
Exciter type: Static
Rated exciter capacity: 95 kW
Rated exciter voltage: 300 V
The equipment is generally well maintained and serviced. Top-turn rewinding of the rotor (the replacement of the copper with silicon-bronze to increase the strength of the rotor top turn coil), which is conducted on F5 gas turbine generators, were conducted on all units between 1993 and 1996.
Fig. 2.2-31 shows a layout of the equipment surrounding the gas turbine and generator. Fig. 2.2- 32 shows the equipment surrounding the generator inlet filter.
As shown in Fig. 2.2-32, the inlet filters of the generator are arranged on both sides in the back of the generator. These filters are subjected to differential pressure control (control value: GOmmAq). The equipment is so designed that, if the control value is exceeded, air will be used to remove dust from the filter element. In this power station, the filter element is water-washed once a year
2-43
in the workshop on the site. It is said that no major trouble has been experienced. This plant can be said a plant of steady operation.
However, such inspections as a pull-up check of the rotor was not conducted. Details are unknown as to the damage of the parts in the generator and the deterioration of the insulation. In general, generators have been operating more than 20 years, those have considerably deteriorated and their performances are much lower than their design values.
Fig. 2.2-33 shows the atmospheric temperature characteristics of the generator output at the time of design in this power station. The generator output changes depending on the temperature of cooling air (or the temperature of the atmosphere if the system is open to the atmosphere) due to the characteristics of the gas turbine and the upper limit temperature of the generator itself.
Table 2.2-16 shows the operation status of the existing generator.
Table 2.2-16. Operational conditions of the generator
Item Unit No.1 No.2 No.3 No.4
Date - ’00. Oct. 16 ’00. Oct. 16 ’00. Oct. 13 ’00. Oct. 17
Gen
erat
or
Inlet Air Temperature (1) °F 94 91 90 91
Inlet Air Temperature (2) °F 90 88 88 89
Active Power MW 18.5 18.8 17.2 17.0
Power Factor
(Calculated value)- 0.95 0.96 0.92 0.96
Comparison of the generator output at the time of design shown in Fig. 2.2-33 and the operational condition of the existing generator indicates that, in terms of design values, the plant can generate up to about 21.3MW if PF = 0.8 at an atmospheric temperature of close to 30°C (86°F), and up to about 24.0MW when PF = 0.9. The current power station only generates 17- 18MW (atmospheric temperature: 30°C) even if the power factor is as high as 0.95, so that it is observed that the performance is actually much lower than the design values. Therefore, to ensure operational reliability in the future, it is recommended to check the damage status of the different parts of the generator and check the status of insulation deterioration of the armature windings (such as insulation diagnosis).
-2-44-
8) Instrument and control
The system is generally well maintained and serviced. However, it has been operating for more than 20 years. The spare parts of the instruments are hard to obtain. The gas turbine control unit is in a particularly difficult situation. It is called Mark II, manufactured by GE of the USA and is a product as two generations older. Transistor-based 1C boards (modules of an integrated circuit) are now difficult to obtain. Like frame detectors and spark plugs, some parts are frequently replaced but the replacement parts used are past the manufacturer-recommended use-by dates. Most detectors have been used since the plant was built.
As for the gas flow meter, its operation unit is out of order. That unit performs operations on signals from the differential pressure transmitter, temperature detector (RTD), and pressure transmitter and produces fuel gas flow rates. The fuel flow rates to each unit were not detected.
This power station has a compartment housing a complete set of controlling equipment as a supplement to the gas turbine compartment. And more, a remote operation panel is installed in the control room (remote control room) on the second floor of the administrator building, which enables central monitoring and control. When the GT is actually started, personnel is assigned not only to this remote control room but also to the local control room, gas compressor, and gas cooler, along with other equipment for the purpose of monitoring and operation.
Table 2.2-17 shows an overview of the control room, while Fig. 2.2-34 shows an external view of the current gas turbine controlling board and remote operation panel.
2-48
Table 2.2-17 Result of Plant Research (l&C) / KORANGI GT PSClassification Item Description Note
I Outline of Plant Operation 1 formal Operation Style Base f DSW WSS / Peak
2 oad Dispatch Control Yes(7 Nq)
3 Total Number of Operators and Their Position [1/Unit, 1/Gas Compressor, 1/Cooling Tower, 1/MC ]
4 Total Number of Shift [ 1 shift ]
n Special Operation 1 Island Operation
2 Phase Modify Operation Yes(7 Nq)
3 Blackout Start Operation
H Configuration of l&C System 1 Layout of Central Control Room [ 5 ]pane Is [ 0 ]desk type controllers 1 Gas Turbine Remote Panel/unit1 Common Equipment Control Board/PS
2 Layout of Control Equipment Room [ 3 ]pane I s/un it [ 0 ]desk type control Iers
3 Location of Local Control Panels [ 1 ]pane I/Gas Fuel Compressor
4 l&C System Configuration
IV Control Equipment 1 Maker & Type of GT Control Panel Maker[HITACHI/GE] Type[ Mark n] Date[1977/ ]
2 Maker & Type of AVR Maker[HITACHI] Type[ ] Date[1977/ ]
3Maker & Type of Protection Control Ier(Relay) forElectric Equipment Maker[HITACHI] Type[ ] Date[1977/ ]
4 Maker & Type of TSI Maker[HITACHI] Type[ ] Date[1977/ ]
5 Maker & Type of DCS Maker[ - ] Type[ ] Date[ / ]
6 Maker & Type of Environmental Monitors Maker[ - ] Type[ ] Date[ / ]
7 Maker & Type of Other Control Equipment Maker[ - ] Type[ ] Date[ / ]
V Control Equipment condition (Latest Date of Replacement or Repair )
1 GT Control Panel Renewa I [ YesCJ No) ] Date [ / / ]
2 AVR Renewal [ YesVJJcP] Date[ / / ]
3 Protection Control Ier(Relay) for Electric Equipment Renewal [ YesL/JkP] Date[ / / ]
4 TSI RenewaC[ YejCl Nq)] Date[ / / ] * Some vibration sensors have beenreplaced.
5 DCS Renewa1[ Yes / No ] Date[ / / ]
6 EnvironmentaI Monitors Renewal[ Yes / No ] Date[ / / ]
7 Transmitters Renewal [ Yes / No ] Date[ / / ]
8 Other Control Equipment Renewa1[ Yes /No] Date[ / / ]
VI Plant management Function 1 Sequence of Event Recording Function Yes <Z No)
2 Plant Performance Calculate Function Yes <Z No)
3 Life monitoring Function of GT Yes </L Nq/>
4 Vibration Monitoring Function of Turbine or Auxiliaries Yes Q Nq) [ ]5 Others Yes <Z No)
vn Extent of Control Room & Control Power Capacity
1 Extent of Central Control Room [ enough space for additional operator board ]
2 Extent of Control Equipment Room [ No space ]
3 Open space or Additional Control Equipment Room [ enough space around the Power Station]
4 Control Power Supply Capacity [ ]kVA
YE Others 1 History of accident Field Ground/all 4 unit, GT Blade Damage/only 1 unit
2 Improvement demand for l&C GT Controller and some instruments3 Environmental Limitations No Limitation
AVR : Automatic Voltage Regulator TSI : Turbine Supervisory Instrument DCS : Dispatch Control System
9) Site arrangement
The layout of this power station is shown in Fig. 2.2-35. The site of this power station is a rectangle 122 m east to west and 152 m south to north, in an industrial zone and a flat geographical land.
Four gas turbines are installed about the middle of the site, along a south-to-north axial direction. Unit No.1 to 4 is arranged as viewed from the west of the site.
Each gas turbine unit has a gas turbine, generator, and main transformer. In the northeast of the gas turbines are a gas cooler and a cooling water pump as a cooling water system. Fuel equipment having a fuel tank and its auxiliary equipment (pump) is arranged to the east of the gas turbines. Power is transmitted to the south of the gas turbines, where a grid station is installed. To the west and southwest of the gas turbines are a shed for gas compressor, an electric room, and a control room, along with other facilities.
The changes made from the original layout are below,
1) The access gate installed in the northwest of the site is closed. To the south of the site is a new access gate.
2) The workshop and storeroom installed to the north of the gas turbines are moved to the northwest of the earlier positions.
3) Mosque and vegetation area are on an internal road 6 m wide between the gas turbines on the one hand and the workshop and store room on the other.
4) To the north of the grid station are two transformers. Two transformers were planned to be installed to the west of the grid station but were not installed.
I I
\ /W
lWN
fTcow
rmx oom
. I lo
.o. h
it/ \ h,saq
, kjt
>I>
I
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'UVi
Fig. 2.2-35 Site Layout of KORANGI GT PS
2-52-53
THTI
T
- Positions of taking photograph
Positions of taking photograph are shown in the below drawing. The numbers like Q) show the positions, and the arrows shown the directions of taking photographs. The direction is shown in this drawing.
wnvwi.osn£n*tpao«)\ !
rtO
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-2-54-
2.2.2 SITE GT PS
(1) Equipment overview
This power station is located in the industrial area about 20 km northwest of Karachi city. Five gas turbine power generating units of model PG-5341 and having an output of 19,500 kW (at an atmospheric temperature of 40°C), along with accompanying equipment in this power station. These units were put into commercial operation in 1979.
This power station is located in a dry climate area and more than 5 km from the nearest water source (river). Consideration has been given to the modification of this power station into a combined-cycle plant but it was never implemented because water supply for steam and cooling water is hard.
Operating time and numbers of start and shutdown of each unit to October 2000 are below,
Unit 1: 61,863h, 4,808 times
Unit 2: 70,198h, 4,823 times
Unit 3: 45,276h, 3,959 times
Unit 4: 57,534h, 4,176 times
Unit 5: 30,356h, 2,634 times
Since the fuel price becomes higher, these facilities are only operated during the peak hours between 18:00 and 24:00. The equipment can be operated on both natural gas and HSDO. But the plants are operated by natural gas (which is cheaper) at 95 % and by HSDO at the remaining 5 % on a power consumption basis.
The equipment is generally maintained in a good condition. However, it has been operating for 21 years and has undergone longer overhaul intervals of virtually 7 to 8 years (which represents an interval of 24,000 operating hours as recommended, but the plants are only operated during the peak hours). This interval is longer than the standard in Japan, which is 2 to 3 years, resulting a decline in the power generator output and efficiency.
Some remarks concerning the deterioration of the gas turbine auxiliary equipment are below.
1) A rise in filter cleaning frequency due to a dirty inlet air filter.
2) The gas flow meter gives defective readings, thus making it difficult to evaluate the unit price of power generated inside this power station.
3) A decline in the output that is considered to be due to a decline in the performance of the gas turbine compressor.
Table 2.2-18 to 2.2-28 show the results of the field survey and hearing in this power station.
2-62
E9-Z
Table 2.2-18 Summary of Inspection Results (1)SITE GT PS Unit No.1 (GT-242) Unit No.2 (GT-243) Unit No.3 (GT-244) Unit No.4 (GT-245) Unit No.5 (GT-246)
No. Inspection Item Inspection Results1 Unit operating condition
(1) Fired Starts (times) 4,808 4,823 3,959 4,176 2,634(2) Fired Hours (hours) 61,863 70,198 45,276 57,534 30,356(3) Operating Load (MW) 17 19 17 - 18(4) Exhaust Temperature (°C) 502 496 496 - 510(5) Operation Mode Base Load Operation Base Load Operation Base Load Operation Base Load Operation Base Load Operation(6) Fuel Type Natural Gas
(HSDO for emergency)Natural Gas
(HSDO for emergency)Natural Gas
(HSDO for emergency)Natural Gas
(HSDO for emergency)Natural Gas
(HSDO for emergency)2 Maintenance History 1.Major overhoulings
were carried out every 24,000 hours (Total 3 times)
1.Major overhoulings were carried out every 24,000 hours (Total 3 times)
1.Major overhoulings were carried out every 24,000 hours (Total 3 times)
1.Major overhoulings were carried out every 24,000 hours (Total 3 times)
1.Major overhoulings were carried out every 24,000 hours (Total 3 times)
3 Damaged Parts & Equipments 1 .Gas flow meter 1 Gas flow meter 1 Gas flow meter 1 Gas flow meter 1 Gas flow meter
4 Isolation1) Gas Purge2) Isolation Plate
Not Applicable Not Applicable Not Applicable Not Applicable Not Applicable
2-64
Table 2.2-19 Summary of Inspection Results (2)SITE GT PS Unit No.1 (GT-242)|Unit No.2 (GT-243) Unit No 3 (GT-244) Unit No.4 (GT-245) Unit No.5 (GT-246)
No. Inspection Item Inspection Method Inspection Results5 Inlet House
1) Filter Visual Inspection re-usedrecommend using self cleaning type
re-usedrecommend using self cleaning type
re-usedrecommend using self cleaning type
re-usedrecommend using self cleaning type
re-usedrecommend using self cleaning type
2) Blow in Door Visual InspectionCheck operating condition
3) Inlet House Inside Visual Inspection re-used re-used re-used re-used re-used6 Enclosure Duct
1) Turbine Room Duct Visual Inspection re-used re-used re-used re-used re-used2) Reduction Room
DuctVisual Inspection re-used re-used re-used re-used re-used
7 Circulation Fan1) Bearing Lube Oil Check lube oil amounts Should be checked. Should be checked. Should be checked. Should be checked. Should be checked.2) Check Fan Surface Visual inspection Should be checked. Should be checked. Should be checked. Should be checked. Should be checked.
8 Inlet Duct1) Inspect Duct inside Visual inspection Should be checked. Should be checked. Should be checked. Should be checked. Should be checked.
9 Inlet Plenum1) Inspect Plenum inside Visual inspection Should be checked. Should be checked. Should be checked. Should be checked. Should be checked.
10 Exhaust Plenum1) Inspect Duct inside2) Exhaust Thermocouple
Visual inspection Should be checked. Should be checked. Should be checked. Should be checked. Should be checked.
11 Exhaust Duct1) Expansion Joint2) Inspect Duct inside3) Check Foundation
Bolts
Visual inspection Should be checked. Should be checked. Should be checked. Should be checked. Should be checked.
2-65
Table 2.2-20 Summary of Inspection Results (3)SITE GT PS Unit No.1 (GT-242) Unit No.2 (GT-243) Unit No.3 (GT-244) Unit No.4 (GT-245) Unit No.5 (GT-246)
No. Inspection Item Inspection Method Inspection Results12 Casing
1) Compressor Inlet Casing
Visual inspection Should be checked. Should be checked. Should be checked. Should be checked. Should be checked.
2) CompressorMiddle, Discharge Casing
Visual inspection Should be checked. Should be checked. Should be checked. Should be checked. Should be checked.
3) Turbine Shell Casinga) 1st Stage Shroud Visual inspection Should be checked.
If necessary replaced by new ones.
Should be checked.If necessary replaced by new ones.
Should be checked.If necessary replaced by new ones.
Should be checked.If necessary replaced by new ones.
Should be checked.If necessary replaced by new ones.
b) 2 nd Stage Shroud Visual inspection Should be checked.If necessary replaced by new ones.
Should be checked.If necessary replaced by new ones.
Should be checked.If necessary replaced by new ones.
Should be checked.If necessary replaced by new ones.
Should be checked.If necessary replaced by new ones.
c) Plug for Bore Scope Visual inspection Should be checked. Should be checked. Should be checked. Should be checked. Should be checked.
d) Exhaust Hood Visual inspection PT inspection
Should be checked.If necessary replaced by new ones.
Should be checked.If necessary replaced by new ones.
Should be checked.If necessary replaced by new ones.
Should be checked.If necessary replaced by new ones.
Should be checked.If necessary replaced by new ones.
e) Exhaust Drum Visual inspection Should be checked. Replace by new one if necessary.
Should be checked. Replace by new one if necessary.
Should be checked. Replace by new one if necessary.
Should be checked. Replace by new one if necessary.
Should be checked. Replace by new one if necessary.
99-2
Table 2.2-21 Summary of Inspection Results (4)SITE GT PS Unit No.1 (GT-242) | Unit No 2 (GT-243) Unit No 3 (GT-244) Unit No.4 (GT-245) Unit No.5 (GT-246)
No. Inspection Item Inspection Method Inspection Results13 Combustor
1) Fuel Nozzle Visual inspectionPT inspection
Should be checked.If necessary replaced by new ones
Should be checked.If necessary replaced by new ones
Should be checked.If necessary replaced by new ones
Should be checked.If necessary replaced by new ones
Should be checked.If necessary replaced by new ones
2) Combustion Chamber
Visual inspectionPT inspection
Should be checked. Should be checked. Should be checked. Should be checked. Should be checked.
3) Combustion Liner Visual inspectionPT inspection Clearance Check
Should be checked.If necessary replaced by new ones
Should be checked.If necessary replaced by new ones
Should be checked.If necessary replaced by new ones
Should be checked.If necessary replaced by new ones
Should be checked.If necessary replaced by new ones
4) Transition Piece Visual inspectionPT inspection
Side Seal Plate Wear condition Check
Clearance Check
Should be checked.If necessary replaced by new ones
Should be checked.If necessary replaced by new ones
Should be checked.If necessary replaced by new ones
Should be checked.If necessary replaced by new ones
Should be checked.If necessary replaced by new ones
5) Cross Fire Tube Visual inspection Should be checked.If necessary replaced by new ones
Should be checked.If necessary replaced by new ones
Should be checked.If necessary replaced by new ones
Should be checked.If necessary replaced by new ones
Should be checked.If necessary replaced by new ones
6) Retainer Visual inspection Should be checked.If necessary replaced by new ones
Should be checked.If necessary replaced by new ones
Should be checked.If necessary replaced by new ones
Should be checked.If necessary replaced by new ones
Should be checked.If necessary replaced by new ones
2-67
Table 2.2-22 Summary of Inspection Results (5)SITE GT PS Unit No.1 (GT-242) | Unit No 2 (GT-243) | Unit No 3 (GT-244) Unit No.4 (GT-245) Unit No.5 (GT-246)
No. Inspection Item Inspection Method Inspection Results14 Rotor, Nozzle
1) Rotor Visual inspection Balancing weight check PT inspection for journal port
From the point of part: life, should be inspected at qualified factory.
From the point of part: life, should be inspected at qualified factory.
From the point of part: life, should be inspected at qualified factory.
From the point of part: life, should be inspected at qualified factory.
From the point of part: life, should be inspected at qualified factory.
2) Compressor Blade Visual inspectionPT inspection
From the point of part: life, should be inspected at qualified factory.
From the point of part: life, should be inspected at qualified factory.
From the point of part: life, should be inspected at qualified factory.
From the point of part: life, should be inspected at qualified factory.
From the point of part: life, should be inspected at qualified factory.
3) Turbine 1st Bucket Visual inspectionPT inspection
From the point of part: life, should be inspected at qualified factory.
From the point of part: life, should be inspected at qualified factory.
From the point of part: life, should be inspected at qualified factory.
From the point of part: life, should be inspected at qualified factory.
From the point of part: life, should be inspected at qualified factory.
4) Turbine 2nd Bucket Visual inspectionPT inspection
From the point of part: life, should be inspected at qualified factory.
From the point of part: life, should be inspected at qualified factory.
From the point of part: life, should be inspected at qualified factory.
From the point of part: life, should be inspected at qualified factory.
From the point of part: life, should be inspected at qualified factory.
5) Turbine 1st Nozzle Visual inspectionPT inspection
From the point of part: life, should be inspected at qualified factory.
From the point of part: life, should be inspected at qualified factory.
From the point of part: life, should be inspected at qualified factory.
From the point of part: life, should be inspected at qualified factory.
From the point of part: life, should be inspected at qualified factory.
6) Turbine 2nd Nozzle Visual inspectionPT inspection
From the point of part: life, should be inspected at qualified factory.
From the point of part: life, should be inspected at qualified factory.
From the point of part: life, should be inspected at qualified factory.
From the point of part: life, should be inspected at qualified factory.
From the point of part: life, should be inspected at qualified factory.
7) Inlet Guide Vane Visual inspectionPT inspectionBush Clearance Check Back rush CheckLVDT rod CheckLimit Switch Check
Should be checked. Should be checked. Should be checked. Should be checked. Should be checked.
2-68
Table 2.2-23 Summary of Inspection Results (6)SITE GT PS Unit No.1 (GT-242) I Unit No 2 (GT-243) I Unit No.3 (GT-244) Unit No.4 (GT-245) Unit No 5 (GT-246)
No. Inspection Item Inspection Method Inspection Results15 Bearing
1) No.1, No.2 Bearing Metal
Visual inspectionFT inspection
Should be checked. And replaced by new one, if necessary
Should be checked. And replaced by new one, if necessary
Should be checked. And replaced by new one, if necessary
Should be checked. And replaced by new one, if necessary
Should be checked. And replaced by new one, if necessary
2) Thrust Bearing Meta Visual inspectionFT inspection
Should be checked. And replaced by new one, if necessary
Should be checked. And replaced by new one, if necessary
Should be checked. And replaced by new one, if necessary
Should be checked. And replaced by new one, if necessary
Should be checked. And replaced by new one, if necessary
3) Bearing Housing Visual inspectionFT inspection
Should be checked. Should be checked. Should be checked. Should be checked. Should be checked.
16 Turbine Overhaul Work1) Jacking Up Jacking up Casing Not applicable. Not applicable. Not applicable. Not applicable. Not applicable.
2) Clearance Check Clearance Check Should be checked during major overhaul.
Should be checked during major overhaul.
Should be checked during major overhaul.
Should be checked during major overhaul.
Should be checked during major overhaul.
3) Rotational Check Rotor Position Check Not applicable. Not applicable. Not applicable. Not applicable. Not applicable.
4) Alignment (ACC~TBXTB~ Reduction Gear)
Alignment Check Adjustment
of Alignment
Should be checked during major overhaul.
Should be checked during major overhaul.
Should be checked during major overhaul.
Should be checked during major overhaul.
Should be checked during major overhaul.
2-69
Table 2.2-24 Summary of Inspection Results (7)SITE GT PS Unit No.1 (GT—242)| Unit No.2 (GT-243) Unit No.3 (GT-244) Unit No.4 (GT-245) Unit No.5 (GT-246)
No. Inspection Item Inspection Method Inspection Results
17 ACC Gear1) ACC Gear Visual inspection
Gear Teeth surface check
Over speed Trip Divide Check
Should be checked. Should be checked. Should be checked. Should be checked. Should be checked.
18 Starting Device1) Torque Converter Operation condition
checkShould be checked. Should be checked. Should be checked Should be checked. Should be checked.
2) Solenoid Valve (20TU)
Operation condition check
Should be checked. Should be checked. Should be checked Should be checked. Should be checked.
3) Lube Oil Pump for Torque Converter
Operation condition check
Should be checked. Should be checked. Should be checked. Should be checked. Should be checked.
4) Starting Motor Visual inspection Operation condition check
Not applicable. Not applicable. Not applicable. Should be checked. Should be checked.
5) Starting Diesel Visual inspection Operation condition check
Should be checked. Should be checked. Should be checked. Not applicable. Not applicable.
6) Starting Clutch Visual inspection Operation condition check
Should be checked. Should be checked. Should be checked. Should be checked. Should be checked.
19 Ratcheting Device1) Ratcheting Oil
PumpVisual inspection Operation condition check
Should be checked. Should be checked. Should be checked. Should be checked. Should be checked.
2) Line Filter Visual inspection Element change if necessary
Should be checked. Should be checked. Should be checked. Should be checked. Should be checked.
3) Ratcheting System Visual inspection Operation condition check
Should be checked. Should be checked. Should be checked. Should be checked. Should be checked.
OA-
Z
Table 2.2-25 Summary of Inspection Results (8)SITE GT PS Unit No.1 (GT-242)| Unit No.2 (GT-243) I Unit No 3 (GT-244) Unit No.4 (GT-245) Unit No.5 (GT-246)
No. Inspection Item Inspection Method Inspection Results20 Lubricant Oil System
1) Lube Oil Filter Visual inspectionElement change if necessary O-ring Change if necessary
Should be replaced by new one per year.
Should be replaced by new one per year.
Should be replaced by new one per year.
Should be replaced by new one per year.
Should be replaced by new one per year.
2) Oil Trip Line Filter Visual inspectionElement change if necessary Gasket change
Should be replaced by new one once per 3 years.
Should be replaced by new one once per 3 years.
Should be replaced by new one once per 3 years.
Should be replaced by new one once per 3 years.
Should be replaced by new one once per 3 years.
3) Coupling Oil Filter Visual inspectionElement change if necessary Gasket change
Should be replaced by new one once per 3 year.
Should be replaced by new one once per 3 year.
Should be replaced by new one once per 3 year.
Should be replaced by new one once per 3 year.
Should be replaced by new one once per 3 year.
4) Mist Separator Visual inspectionElement change if necessary Gasket change
Not applicable. Not applicable. Not applicable. Not applicable. Not applicable.
5) Mist SeparatorFan
Visual inspection Not applicable. Not applicable. Not applicable. Not applicable. Not applicable.
6) Lube Oil Cooler Visual inspectionPacking change if necessary Leakage check
Should be cleanedonce per year.
Should be cleanedonce per year.
Should be cleanedonce per year.
Should be cleanedonce per year.
Should be cleanedonce per year.
7) Main Lube OilPump
Visual inspectionPT inspectionCoupling visual inspection
Should be checked. Should be checked. Should be checked. Should be checked. Should be checked.
8) Aux. Lube OilPump
Operation condition check Should be checked. Should be checked. Should be checked. Should be checked. Should be checked.
9) Emergency LubeOil Pump
Operation condition check Should be checked. Should be checked. Should be checked. Should be checked. Should be checked.
10) Pressure Regulator (VPR-1)
Operation condition check Should be checked. Should be checked. Should be checked. Should be checked. Should be checked.
11) Pressure Regulator (VPR-2)
Operation condition check Should be checked. Should be checked. Should be checked. Should be checked. Should be checked.
12) Lube Oil Tank Visual inspection Should be checked. Should be checked. Should be checked. Should be checked. Should be checked.
2-71
Table 2.2-26 Summary of Inspection Results (9)SITE GT PS Unit No.1 (GT-242) I Unit No.2 (GT-243) | Unit No.3 (GT-244) Unit No.4 (GT-245) Unit No.5 (GT-246)
No. Inspection Item Inspection Method Inspection Results21 Control Oil System
1) Control Oil Filter Visual inspection Element change if necessary
Should be checked. Should be checked. Should be checked. Should be checked. Should be checked.
2) Control Oil Strainer Visual inspection Element Cleaning
Should be checked. Should be checked. Should be checked. Should be checked. Should be checked.
3) Main Control Oil Pump
Replaced by new one Inspect the quill shaft by PT
Should be checked. Should be checked. Should be checked. Should be checked. Should be checked.
4) Aux. Control Oil Pump
Operation condition check
Should be checked. Should be checked. Should be checked. Should be checked. Should be checked.
5) Accumulator Gas Pressure Check spec; 63kg/cm2
Should be checked. Should be checked. Should be checked. Should be checked. Should be checked.
6) Solenoid Valve
(20FG-A)
Operation condition check
Not applicable. Not applicable. Not applicable. Not applicable. Not applicable.
7) Solenoid Valve
(20FG-A)
Operation condition check
Not applicable. Not applicable. Not applicable. Not applicable. Not applicable.
22 Cooling and SealingAir System
1) 6 stage Extraction Valve
Operation condition check
Should be checked. Should be checked. Should be checked. Should be checked. Should be checked.
2) 11 Stage Extraction Valve
Operation condition check
Should be checked. Should be checked. Should be checked. Should be checked. Should be checked.
3) Orifice Size Visual inspection Compressor Side: 2 pcs Turbine Side: 4 pcs Compressor Discharge Line
Should be checked during major overhaul.
Should be checked during major overhaul.
Should be checked during major overhaul.
Should be checked during major overhaul.
Should be checked during major overhaul.
23 Cooling Water System1) Temperature
Control Valve (VTR-1)
Operation condition check
Should be checked and replaced by new one if necessary.
Should be checked and replaced by new one if necessary.
Should be checked and replaced by new one if necessary.
Should be checked and replaced by new one if necessary.
Should be checked and replaced by new one if necessary.
2) Turbine support Water jacket
Visual inspection Not applicable. Not applicable. Not applicable. Not applicable. Not applicable.
Table 2.2-27 Summary of Inspection Results (10)
SITE GT PS Unit No.1 (GT-242) | Unit No.2 (GT-243) | Unit No.3 (GT-244) | Unit No.4 (GT-245) | Unit No.5 (GT-246)No. Inspection Item Inspection Method Inspection Results
3) Cooling Pipes Visual inspection Should be cleaned during major overhaul.
Should be cleaned during major overhaul.
Should be cleaned during major overhaul.
Should be cleaned during major overhaul.
Should be cleaned during major overhaul.
24 Fuel Gas System1) Gas Strainer Visual inspection Should be cleaned
periodical.Should be cleaned periodical.
Should be cleaned periodical.
Should be cleaned periodical.
Should be cleaned periodical.
2) SRV/GCV Visual inspectionGasket change if necessary
LVDT visual inspection Leakage checkOperation condition check
Should be checked. Should be checked. Should be checked. Should be checked. Should be checked.
3) Gas flow meter Visual inspection & hearing
Should be replaced by new one.
Should be replaced bynew one.
Should be replaced by new one.
Should be replaced bynew one.
Should be replaced bynew one.
25 Fuel Oil System1) Main fuel pump2) HP filter3) By-pass control valve4) Fuel stop valve5) Flow meter
Visual inspectionCheck differentialpressure
Visual inspection
Should be checked. Should be checked. Should be checked. Should be checked. Should be checked.
26 Atomizing air system1) Atomizing compressor2) Pre-cooler3) After-cooler4) Air separator5) Air filter6) Booster compressor
Visual inspectionVisual inspection
Check differential pressure Check differential pressure
Not applicable Not applicable Not applicable Not applicable Not applicable
27 Piping1) Cooling and Sealing
Air PipeVisual inspection Should be cleaned
during major overhaul.Should be cleaned during major overhaul.
Should be cleaned during major overhaul.
Should be cleaned during major overhaul.
Should be cleaned during major overhaul.
2) Exhaust FlameCooling Air Pipe
Visual inspection Not applicable. Not applicable. Not applicable. Not applicable. Not applicable.
3) Fuel Gas Pipe Visual inspection Should be cleaned during major overhaul.
Should be cleaned during major overhaul.
Should be cleaned during major overhaul.
Should be cleaned during major overhaul.
Should be cleaned during major overhaul.
4) Leakage Check Should be checked duringmajor overhaul.
Should be checked duringmajor overhaul.
Should be checked duringmajor overhaul,
Should be checked duringmajor overhaul.
Should be checked duringmajor overhaul.
Table 2.2-28 Summary of Inspection Results (11)SITE GT PS Unit No.1 (GT-242) | Unit No.2 (GT-243) | Unit No.3 (GT-244) | Unit No.4 (GT-245) | Unit No.5 (GT-246)
No. Inspection Item Inspection Method Inspection Results28 Instrument
1) Servo Valve90SR, 90TV, 65GC
Lift Calibration Check Visual inspection
Should be replaced by new one from the point of parts life.
Should be replaced by new one from the point of parts life.
Should be replaced by new one from the point of parts life.
Should be replaced by new one from the point of parts life.
Should be replaced by new one from the point of parts life.
2) Speed Sensor77NH-1,2,3
Gap checkVisual inspection
Should be checked during major overhaul.
Should be checked during major overhaul.
Should be checked during major overhaul.
Should be checked during major overhaul.
Should be checked during major overhaul.
3) Transformer (LVDT)
Lift Calibration Check Should be checked during major overhaul
Should be checked during major overhaul
Should be checked during major overhaul
Should be checked during major overhaul
Should be checked during major overhaul
4) Flame Detector (28FD)
Operation condition check Replace spare if necessary
Should be checked periodically.
Should be checked periodically.
Should be checked periodically.
Should be checked periodically.
Should be checked periodically.
5) Spark Plugand Transformer
Operation condition check Should be checked periodically.
Should be checked periodically.
Should be checked periodically.
Should be checked periodically.
Should be checked periodically.
6) Vibration Sensor Characteristic check Should be calibrated periodically.
Should be calibrated periodically.
Should be calibrated periodically.
Should be calibrated periodically.
Should be calibrated periodically.
7) Axial Vibration Sensor Characteristic check Not applicable. Not applicable. Not applicable. Not applicable. Not applicable.
8) ExhaustThermocouples
Characteristic check Should be checked periodically.
Should be checked periodically.
Should be checked periodically.
Should be checked periodically.
Should be checked periodically.
9) Wheelspace Thermocouples
Characteristic check Should be checked periodically.
Should be checked periodically.
Should be checked periodically.
Should be checked periodically.
Should be checked periodically.
10) Lube OilThermocouples
Characteristic check Should be checked periodically.
Should be checked periodically.
Should be checked periodically.
Should be checked periodically.
Should be checked periodically.
29 C02 Fire Fighting System1) C02 Gas Pressure Visual inspection Should be checked
periodically.Should be checked periodically.
Should be checked periodically.
Should be checked periodically.
Should be checked periodically.
2) C02 Control Panel Operation condition check Should be checked periodically.
Should be checked periodically.
Should be checked periodically.
Should be checked periodically.
Should be checked periodically.
30 Isolation1) N2 purge
Fuel Gas engagedNot applicable. Not applicable. Not applicable. Not applicable. Not applicable.
(2) Status of the equipment
1) Existing F5 gas turbine equipment
An overview of this power station is shown in Fig. 2.2-36. The specifications of the major equipment are as shown in Table 2.2-29. As indicated in Fig. 2.2-37 to 2.2-40, the package appearance of the gas turbine equipment and the premises are serviced relatively well. The gas turbine casing, combustor and their surroundings are also well serviced as shown in Fig. 2.2-41. However, assuming from the results of the latest major overhauling inspection on the KORANGI GT PS, the casing seems to contain a much-progressed secular deterioration, such as cracks. As shown in Fig. 2.2-42, the fuel distribution pipe is removed from the fuel nozzles and this plant does not seem to have been operated on HSDO in recent years.
The internal status of the gas turbine auxiliary equipment house is shown in Fig. 2.2-43 to 2.2-46. It shows no non-conformances that may cause functional problems, thus demonstrating that it is appropriately maintained.
2) Inlet air filter
Fig. 2.2-47 shows an overview of the boundary in the west of this power station. To the west of this power station is a chemical plant (an edible oil plant). Smoke emissions of the plant stick to the inlet air filter of this power station, thus accelerating the dirtying of the filter (Fig. 2.2-48). This power station is located in a dry climate area, so that the air filter is easily dirtied. And more, factories and other facilities were added on in the surroundings. We think that these are the reasons why such problems have come to the surface. Replacing with a self-cleaning type, thus reducing the frequency of cleaning required and delaying the decline in the power generator output and efficiency can hopefully enhance the equipment.
2-74
1. Gas TurbineTable 2.2-29 Specification of Major Mechanical Equipment
Manufacturer Hitachi, Ltd.Type Open-Cycle, Single-Shaft, Industrial Type Gas TurbineModel Hitachi PG-5341
Compressor Type Axial Flow TypeNumber of Stages 17 StagesCombustor Type Cannular TypeNumber of Quantities 10 CansTurbine Type Axial Flow, 1st Stage; Impulse and 2nd Stage; Reaction TypeNumber of Quantities 2 StagesShaft Speed 5,100 rpmDirection of Rotation Clockwise viewed from output couplingOver speed Trip Setting Electrical Over Speed; 5,610±30 rpm(109.41~ 110.59%)
Mechanical Over Speed; 5,738±50 rpm(111.53^113.49%)Gas Turbine Rotor Weight Approx. 9 Tons2. Reduction GearManufacture Hitachi, Ltd.Type Quill Shaft- Double Helical GearGear Speed Turbine Side; 5,100 rpm, Generator Side; 3,000 rpm3. Turning EquipmentTurning Speed Approx. 1~2 revolution/hrTurning Method Hydraulic Ratchet SystemNormal Turning Period after Approx. 24 hoursOperation at Base Load4. Starting EquipmentType of Starter Diesel Engine (for No.1 ~No.3)/ Motor (for No.4, No.5)Capacity 500 HP/400 HPStarting Time to Full Load Normal; 11 min. Fast; 7 min. 30 sec.5. Exhaust SystemType of Silencer Parallel Baffle Type, 10 ftMaterial of Sound Absorber Rock WoolMaximum Pressure Loss 20 mmAqMaterial of Expansion Joints Stainless Steel and Teflon Cloth
-2-75
6. Inlet Air Filter(1) 1st Stage Filter Type Inertial Separation Type
(2) Bleed Fan
Type Radial Fan
Quantity 2 per Unit
Capacity 290 m3/min.
Static Pressure 90 mmAq (at 40°C)
(3) Motor
Capacity 11 kW
Number of Pole 4
Voltage AC 400V
Frequency 50 Hz
Insulation Type B
(4) Second Stage Filter
Type Bag Type (Washable Type)
Media Material Polyester Fiber
Quantity Full Size: 80 pcs, Half Size: 16 pcs.
Capacity 5,800 m3/min.
Pressure Drop Initial: 13.6 mmAq, Final: 20 mmAq.
(5) Emergency Dumper
Quantity 1 set
Cracking Pressure 75 mmAq (Vacuum)
2-76
4) Fuel supply system
a) Gas compressor
This gas compressor has been operating since 1980 to supply natural gas for the existing F5 gas turbine. One gas compressor fuels each gas turbine. A total of five units are installed.
No. 1 - serial number: 76A1102901, model: 110OkW, BTD-ICC
No. 2 - serial number: 76A1102902, model: 1100kW, BTD-ICC
No. 3 - serial number: 76A1102903, model: 110OkW, BTD-ICC
No. 4 - serial number: 76A1102904, model: 1100kW, BTD-ICC
No. 5 - serial number: 76A1102905, model: 1100kW, BTD-ICC
The existing gas compressor specifications are shown in Table 2.2-30, and a flow sheet is shown in Fig. 2.2-52. Fig. 2.2-53 shows the number of gas turbines that can be operated due to the change in the suction pressure of existing gas compressors. When suction pressure is 60 psig or less, one unit of gas turbine is operated for one unit of gas compressor. There is no standby unit.
Table 2.2-31 shows the total operating time of the existing gas compressors from the start-up of their operation to October 31, 2000.
Table 2.2-31 Operating Time of Gas Compressors
~~ —-—___JJni^No^ No.1 No.2 No.3 No.4 No.5
Total operating time (h) 9,571 18,170 19,063 19,833 12,240
In Japan, gas compressor is overhauled every 8,000 hours. From August to September 2000, first overhaul was conducted on No. 2 only. None of the other units has been subjected to any major overhaul.
Due to the power demand in Karachi city, the gas compressors are stopped during the daytime. During this survey, therefore, the condition during the operation could not be conducted. The operation status based on an appearance inspection of the stopped gas compressors and the log sheets obtained from this power station are reported.
All of five gas compressors were operable.
-2-86-
Table 2.2-30 Original Specification for Gas Compressor (SITE GT PS)
Item Unit Design Data
Number of units — 5
Type — BTD-ICC
Serial number — 78A1102901 —05
1st stage suction pressure psig 30-200
2nd stage discharge pressure psig 220
Gas capacity kg/h7,500(at 30psig)
30,000(at ISOpsig)
Suction temperature °C 9-29.4
Gas Component
mol %
ch4 94.42
C2H6 1.05
CgHg 0.28
X0
0.12
C5H12 0.05
N2 3 89
C02 0.02
02 0.17
Molar weight — 16.85
Cylinder lubrication — Yes
Cylinder diameterx unit 1st stage (mm) 0615X1
2nd stage (mm) 0466X1
Piston rod diameter mm *90
Stroke mm 315
Speed min'1 369
Driver type — Induction motor
Output power of main motor kW 1100
-2-87
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OIL PRESSURE SWITCH
DRAIN TRAP
SAFETY VALVE
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3 WAY SoLEB/O/D VALVE
MOTOR
CHECK VALVE
OIL FILTEROIL STRAINER
FLOW SWITCH
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THE KARACHI ELECTRIC SUPPLY CORPORATION LIMITED
S.l.T.E. GAS TURBINE POWER STATION
CONSULTANTS : FICHTNER, CONSULTING ENGINEERS
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FLOW DIAGRAM
FOR REFERENCE
Fig. 2.2-52 Flow Diagram of Existing Gas Compressor
® Gas compressor suction line (Fig. 2.2-56)
Slot 1»n
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Fig. 2.2-56 Flow Chart of Gas Compressor Suction Line
3) Natural gas supplied to the gas compressor
Gas composition
Name Vol%
Methane (C H 4) 94.36
Ethane (C2 H6) 0.96
Propane (C3H8) 0.28
Butane (C4 H ^ 0) 0.15
Oxygen (02) 0.17 to 1.0
Nitrogen (N 2) 3.98 to 4.10
Carbon dioxide (C02) 0.02 to 0.06
2-90-
(§) Representative log sheet of the gas compressor
Table 2.2-15 shows the ranges of each item in the log sheet obtained as representative data from this power station.
Table 2.2-15. Log Sheet of Gas Compressor (SITE GT PS)
Item Units Data
Suction pressure: P, point A psig 61 to 144
Discharge pressure psig 213 to 225
Suction temperature: T, point A °C 23 to 56
Discharge temperature First stage 70 to 124
Second stage °c 72 to 122After the after-cooler 41 to 105
Cooling water supply temperature (radiator outlet)
°c 31 to 68
Cooling water outlet temperatureOil cooler No dataInter-cooler °c
47 to 76After-cooler No data
Current of main motor A No data
*: Represents point A in the flowchart of the suction line in Fig. 2.2-56.
As supplementary information for Table 2.2-32, some information were obtained about the previous trends in the matters mentioned below that affect the performance of the gas compressor, by a hearing with this power station staff.
Suction pressure: P, point A*, 50 to 150 psig (90 to 100 psig average)
b) Fuel supply equipment
Total power generation of this power station depends on natural gas for 95% and on HSDO for 5%. As indicated in Figs. 2.2-57 and 2.2-58, the system is provided with a fuel oil heater but it is now not used.
c) Gas flow meter
For the gas flow meter (Fig. 2.2-59), all of them on the five gas turbines have long been in non-working condition. Based on the results of a hearing, it was estimated that this was due to a breakdown of the calculating unit. However, the pressure
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transmitter (Fig. 2.2-60) has long been provided with no calibration or other adjustment, so that it has declined in instrument reliability. The replacement of the gas flow meter is imperative if one wishes to monitor the time-series changes such as dirt in the air compressor, thus operating the gas turbine equipment soundly and economically.
d) Gas control skid
Even when the gas turbine is down and the gas supply is suspended, the gas pressure does not read zero. There may be an instrument drift or a valve seat leak as shown in Fig. 2.2-61. It is desirable to check the system and take an action soon to ensure safety.
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5) Electrical system
The specifications of the major electrical equipment are as follows:
Substation bus Generator
Neutral ground transformer Neutral ground resister (NGR)Generator circuit breaker Set-up transformer Main auxiliary transformer Excitation transformer
132kV, 50Hz, 2500A, 31.5kA 27,687kVA(at 26.7°C), 11500V, 50Hz, 0.8PF
10kVA, 12kV/240V 1.080, 205A, 1min
MBB, 13.8kV, 2000A, 500MVA 22/30MVA, 132kV±2X2.5%, LV:11.5kV 120kVA(ONAN), 11500V, 420V-380V-360V 230kVA
BatteryCommon auxiliary transformer
200Ah/20h(Lead acid type)2sets, 10MVA, 11.5kV±2x2.5%, 3.45kV
There have been no changes in electrical equipment specifications from the original. Electrical equipment including substation are operated without any trouble.
-2-97-
6) Generator
The basic specifications of the generator are as follows:
Model: Open draft type, 3-phase synchronized generator
Capacity: 27,687 kVA (at an atmospheric temperature of 26.7°C (80°F))
Quantity:
Installed location:
Rated power factor:
Rated output:
Frequency:
Rated engine speed:
Rated voltage:
Number of phases:
Short-circuit ratio:
Insulation type:
Excitation voltage:
Neutral grounding system:
Turning direction:
Exciter type:
Rated exciter capacity:
Rated exciter voltage:
5 units
Outdoors
0.8
22,150 kW
50 Hz
3,000 rpm
11,500 V
3 phases
over 0.49
Type F (JEC-114)
300 V
Neutral point transformer
Clockwise as viewed from turbine
Static
95 kW
300 V
The system is generally well maintained and serviced. Top-turn rewinding (the change of material from copper to silicon-bronze to increase the strength of the rotor top turn coil) of the rotor for which actions were taken in the F5 gas turbine generator was conducted between 1993 and 1996, except for Unit 4.
The layout of the gas turbines and generators, along with their surroundings, is basically identical with the KORANGI GT PS. The inlet filters of the generator are arranged on both sides in the back of the generators. These filters are subjected to differential pressure control (control value : 60mmAq). If the control value is exceeded, the equipment is so designed that air is used to remove dust from the filter element. In this power station, this removal is conducted every two to three months. At a rate of once every three or four years, the filter element is replaced. It is said that no major trouble is experienced, and we would say that this plant is steadily operated.
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However, such inspections as a pull-up check of the rotor was not conducted. Details are unknown as to the damage of the parts in the generator and the deterioration of the insulation. In general, generators have been operating more than 20 years, those have considerably deteriorated and their performances are much lower than their design values.
Fig. 2.2-62 shows the atmospheric temperature characteristics of the generator output of this power station. The generator output changes depending on the temperature of cooling water (or atmospheric temperature in the case of a type open to the atmosphere), due to the characteristics of the gas turbine and the upper limit temperature of the generator itself.
Table 2.2-33 shows the operating status of the existing generator. The data for Unit 4 was not obtained.
Table 2.2-33 Operational Conditions of Generator
Item Unit No.1 No.2 No.3 No.4 No.5
Date - ’OO.Oct.15 'OO.Oct.15 'OO.Oct.15 — 'OO.Oct.15
Gen
erat
or
Inlet AirTemperature
°F 93 93 92 — 97
Active Power MW 17.0 19.0 17.0 — 18.0
Stator Voltage kV 11.0 11.4 11.1 — 11.0
Stator Current kA 1.05 1.09 1.02 — 1.06
Power Factor
(Calculated value)- 0.85 0.88 0.87 — 0.92
Comparison of the generator output at the time of design shown in Fig. 2.2-62 and the operational condition of the existing generator, in terms of design values, the plant can generate up to about 21 3MW if PF = 0.8 at an atmospheric temperature of close to 30°C (86°F), and up to about 24.0MW when PF = 0.9. Today, this plant can only generate 17-18MW (at6 an atmospheric temperature of about 30°C) even if the power factor is increased to about 0.85. This demonstrated that, even though a little better than the KORANGI GT PS, this power station has actually declined similarly much in performance from its design value. Therefore, to ensure operational reliability in the future, it is recommended to check the damage status of the different parts of the generator and check the status of insulation deterioration of the armature windings (such as insulation diagnosis).
2-99
7) Instrument and control
The system is generally well maintained and serviced. However, it has been operating for more than 20 years. The spare parts of the instruments are hard to obtain. The gas turbine control unit is in a particularly difficult situation. It is called Mark II, manufactured by GE of the USA. It belongs to the last but one generation. Transistor-based 1C boards (modules of an integrated circuit) are now difficult to obtain.
As for the gas flow meter, its operation unit is out of order. That unit performs operations on signals from the differential pressure transmitter, temperature detector (RTD), and pressure transmitter and produces fuel gas flow rates. The fuel flow rates to each unit were not detected.
Similarly to the KORANGI GT PS, this power station has a compartment housing a complete set of controlling equipment that is annexed to the gas turbine compartment. And more, a remote control panel is installed in the remote control room on the second floor of the administrator building to allow central monitoring and control. When the GT starts actually, personnel will be assigned to this remote control room, as well as the local control room and the gas compressor for the purposes of monitoring and operation.
Table 2.2-34 shows an overview of the control room, while Fig. 2.2-63 shows an external view of the current gas turbine controlling board and remote operation panel.
2-101-
2-102
Table 2. 2-34 Result of Plant Research (l&C) / SITE GT IPSClassification Item Description Note
I Outline of Plant Operation 1 Normal Operation Style Base /LOSS)/ WSS / Peak
2 Load Dispatch Control Yesd No)
3 Total Number of Operators and Their Position [1/Unit, 1/Gas Compressor, 1/Cooling Tower, 1/MC ]
4 Total Number of Shift [ 1 shift ]
n Special Operation 1 Island Operation YesC/ No)
2 Phase Modify Operation YesQ No)3 Blackout Start Operation YesC/ No)
H Configuration of l&C System 1 Layout of Central Control Room [ 6 ]pane Is [ 0 ]desk type controllers 1 Gas Turbine Remote Panel/unit1 Common Equipment Control Board/PS
2 Layout of Control Equipment Room [ 3 ]pane I s/un it [ 0 ]desk type controllers
3 Location of Local Control Panels [ 1 ]pane I/Gas Fuel Compressor
4 l&C System Configuration
IV Control Equipment 1 Maker & Type of GT Control Panel Maker[HITACHi/GE] Type[ Mark n] Date[1978/ ]
2 Maker & Type of AVR Maker[HITACHI] Type[ ] Date[1978/ ]
3Maker & Type of Protection Control Ier(Re I ay) for ElectricEquipment MakerEHITACHI] Type[ ] Date[1978/ ]
4 Maker & Type of TSI Maker[HITACHI] Type[ ] Date[1978/ ]
5 Maker & Type of DCS Maker[ - ] Type[ ] Date[ / ]
6 Maker & Type of Environmental Monitors Maker[ - ] Type[ ] Date[ / 3
7 Maker & Type of Other Control Equipment Maker[ - ] Type[ ] Date[ / ]
V Control Equipment condition (Latest Date of Replacement or Repair )
1 GT Control Panel Renewa1[ YesfZ N5>] Date[ / / ]
2 AVR Renewal[ Yesv Nti>] Date[ / / ]
3 Protection Control Ier(Re I ay) for Electric Equipment Renewal[ YesC/ Np>] Date[ / / ]
4 TSI Renewa l([ Ye^r/ % ] Date[ / / ] * Some vibration sensors have beenreplaced.
5 DCS Renewa1[ Yes / No ] Date[ / / ]
6 Environmental Monitors Renewa1[ Yes / No ] Date[ / / ]
7 Transmitters Renewal[ Yes / No ] Date[ / / ]
8 Other Control Equipment Renewa1[ Yes / No ] Date[ / / ]
VI Plant management Function 1 Sequence of Event Recording Function YesC/ No)
2 Plant Performance Calculate Function YesC/ No)
3 Life monitoring Function of GT YesC/ No)
4 Vibration Monitoring Function of Turbine or Auxiliaries Yes^ Ny [ 3
5 Others Yesv No])
vn Extent of Control Room &
Control Power Capacity
1 Extent of Central Control Room [ enough space for additional operator board ]
2 Extent of Control Equipment Room [ No space ]
3 Open space or Additional Control Equipment Room [ enough space in the Power Station]
4 Control Power Supply Capacity [ ] kVA
vm Others 1 History of accident2 Improvement demand for l&C GT Controller and some instruments
3 Environmental Limitations No Limitation
AVR : Automatic Voltage Regulator TSI : Turbine Supervisory Instrument DCS : Dispatch Control System
8) Site arrangement
The SITE GT PS is located in the northwest of Karachi city and about 20 km (about 30 minutes' drive) from the city center of Karachi. The layout of this power station is given in Fig. 2.2-64. The site of this power station is a rectangle 190 m east to west, and 115 m south to north. It is in an industrial zone and a flat land.
Five gas turbines are installed about the middle of the site, along a south-to-north axial direction. Unit No. 1 to 5 are arranged as viewed from the west of the site.
Each gas turbine unit has a gas turbine, generator and main transformer. In the accessory compartment for the gas turbine facility, there is a radiator to cool the air.The fuel equipment having a fuel tank and its auxiliary equipment (pump) is arranged to the west of the gas turbine equipment. Power is transmitted to the south of the gas turbine equipment. In that direction, there is a switchgear building, with a switchgear room and a control room. To the east of the gas turbine equipment is a shed for fuel gas compressor.
The changing points from the earlier layout are below:
1) The earlier layout designed the south of the site as a concave shape, while the current one shows it as almost as a rectangle.
2) Regarding 1), the storeroom and workshop have moved to the north.
3) Mosque is built to the east of the switchgear building.
4) Two transformers planned to install to the east of the switchgear are not installed.
5) A common condensate storage tank planned to install to the west of the gas turbine equipment is not installed.
2-105-
um
i Mm j
SWTCHGEAA BUIUXNC
VIEW A-A
2-106-107
■ Positions of taking photograph
Positions of taking photograph are shown in the below drawing. The numbers like ® show the positions, and the arrows shown the directions of taking photographs. The direction is shown in this drawing.
-2-108
2.2.3 Operation status
For both power plants, the gas turbines are operated from evening to night, which is the peak of power demand in Karachi city. That is, the gas turbines are started at 17:00 or 18:00 in the evening, almost every evening, and are stopped around 22:00 or 24:00. Fig. 2.2-65 shows the typical operation pattern of the gas turbines at both power stations.
The gas turbines are operated at full load and not operated at partial load, where the thermal efficiency is lower. When power demand varies day by day, the number of gas turbines in operation is changed to respond.
2.2.4 Degradation status
Although well maintained and operated without major problems, these power stations have now been operating for more than 20 years. Their key components (gas turbine, compressor, generator and other equipment) have considerably degraded, with performance much lower than the design values. Figs. 2.2-66 and 2.2-67 show the atmospheric temperature characteristics of the output and thermal efficiency at the time of design of the gas turbines. The output and thermal efficiency change depending on the atmospheric temperature. Plotting the operation status of each gas turbine in both power stations today, we find that, at atmospheric temperatures of about 33 to 35°C, which are the operation points, the output is 1,500 to 3,500kW and the thermal efficiency is 5 to 6% (absolute value) lower than the design value, thus marking a considerable decline in performance.
The outputs were measurable for each unit in both power stations. Regarding thermal efficiency, all gas flow meters installed on each unit were out of order. Therefore, the average efficiency of this power station were estimated by the fuel consumption of entire power station and plotted it on a graph.
Fig. 2.2-68 and 2.2-69 show the heat balance of both power stations based on the measurements. The heat balance diagram is also displayed in the average of these power stations for the year due to the defect in the gas flow meters.
-2-115-
GT O
utpu
t
0:00 6:00 12:00 18:00 24:00
Time ( hr ) Start up Shut down
17:00-18:00 2400
Fig. 2.2-65 Current Typical Operation Pattern of Gas Turbine for KORANGI GT PS and SITE GT PS
Note; (1) Current GT output is less than original design value due to deterioration.(2) GT outout varies with the ambient temoerature
-2-116
DE
SIG
N T
HER
MAL
EFF
ICIE
NC
Y (%
) <P
D
ESIG
N O
UTP
UT
(kW
)
30,000
25,000
20,000
rUCLINrtl UrXML UttO
ISO CONDITION
15,0000 10 20 30 40
OPERATING STATUS • SITE GT PS
(Oct. 15, 2000)O KORANGI GT PS
(Oct. 16, 2000)
COMPRESSOR INLET TEMPERATURE (°C)
2.2-66 Base Load Design Curve and Operating Status for Existing Gas Turbine Output
OPERATING STATUS (1999-2000 Annual Average)
SITE GT PS KORANGI GT PS
FUELNATURALGAS ISO CONDITION
COMPRESSOR INLET TEMPERATURE (°C)
Fig. 2.2-67 Base Load Design Curve and Operating Status for Existing Gas Turbine Efficiency
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6.143 ke/h
Stack
Generator
16.292 kW
Gas Turbine
(F5)PmrFnrmannA
Gas Turbine Output 16,292 kW
Thermal Efficiency : 20.46 %
Fuel Heating Value : 46381 kJ/kg
Conditions
Ambient Temperature : -°cRelative Humidity
Atmospheric Pressure - kPa
Fig. 2.2-68 Heat Balance Diagram of Existing F5 Gas Turbine Generation Facility
(1999-2000 Annual Averaged Value for KORANGI GT Power Station)
(F5)
Performance
Gas Turbine Output 18,447 kW
Thermal Efficiency 21.67 %
Fuel Heating Value 46,381 kJ/kg
Conditions
Ambient Temperature : - °C Relative Humidity : ~ %
Atmospheric Pressure : - kPa
Fig. 2.2-69 Heat Balance Diagram of Existing F5 Gas Turbine Generation Facility
(1999-2000 Annual Averaged Value for SITE GT Power Station)
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2.3 Project executive capacity of the implementation site
(1) Technical capacity
KESC and the power stations have enough personnel as will be described below. As explained in 2.2, the turbines themselves are periodically checked after a specified running time. They have also been given top-turn rewinding, which is a measure to extend the lives of dynamo rotors. Every power station has a machine tool factory (workshop), which stores spare parts and are able to conduct dismantling and repairs. All executives of the power stations are engineers. At the time of our present survey, we received many technical questions from them, which shows their high technical expertise.
(2) Management system
KESC is a semi-governmental organization, with the government holding 80% of its outstanding shares. The management system is therefore under the control of the military government, which rules the country now. Since November, 1999, Syed Shahid Mukhtar, Army Brigadier in charge of economics, has been in the office of Managing Director of KESC. Zulfiqar AN Khan, Lieutenant General doubling as Chairman of WAP DA, doubles as Chairman of KESC. The main purpose of introducing Army members into KESC is to control the very high losses, increase the work efficiency of the employees, and attempt a financial recovery.
The officers are civilians (KESC's employees). Many of them were replaced after the establishment of the military government. Now, Zahil Abdol Bathid, Senior Chief Engineer (SCE), has been in the position next to the President since December, 2000.
The management system of the power stations is as follows: The Chief Engineer of the Bin Qasim Power Station, which has the largest power plants of all that KESC has, doubles as the Chief Engineer of all power stations. The other power stations are run by the Deputy Chief Engineer as the top-ranking officer of those stations. Each power station is run according to the plan of KESC. All executives of the power stations are engineers, which is part of the reason why the equipment is smoothly maintained and controlled.
(3) The basis and policy of management
As described in 1.2, KESC now has a total power capacity of 1,867 MW. However, the deterioration of the equipment and the fuel shortage, among other circumstances, have resulted in the fact that the maximum electric power actually supplied was 1,474 MW in 1998 and 1,295 MW in 1999. The maximum power demand of 1999 was 1,730 MW, and the shortage was covered by purchases from WAP DA, IPPs and other corporations. The expenses for these power purchases are a factor that is putting pressure on KESC's financial condition. Another burden is a high loss in power transmission, reaching more than 40% on the average. Of which KESC estimates that 19% is due to ordinary losses, and the remaining 20% is due to what is called theft, the
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deterioration of the power transmission lines, and mechanical losses due to poor maintenance. KESC's trial calculations indicate that a power transmission loss of 1% amounts to an annual loss of 480 million rupees (about 80 million dollars). Another major problem is the non-payment of the electric charges. They are actually collected from only about 50% of the consumers.
As a result, KESC's balance has been in the red since fiscal 1995. Table 2.3.1 shows KESC's balance status in fiscal 1997 and 1998. KESC's cumulative losses expanded to 19 billion rupees (about 620 million dollars) by June, 1999.
Table 2.3-1 Income/Expenditure and Loss (million Rs.)
1998 1997 lncr./(Decr.)incoi 116!- Revenue from sale of energy 23,284.92 20,726.39 12.34%- Other Income 496 23 412.56 20.28%
23,781.15 21,138.95 12.50%Expenditure:■ Cost of fuel and power purchased 20/1267 18,208.74 13.75%■ Depreciation 2,726.20 2,139.66 27.41%■ Interest 3,041.65 3,161.41 (3.79%)■ Provision for doubtful debts 1,212.93 1,698.30 (28.58%)■Other expenses 3,452.15 2,787.55 23.84%
31,145.60 27,995.66 11.25%ProfitZ(Loss) (7,364.45) (6,856.71) 7 41%
To correct the situation, KESC has been working hard to catch electricity thieves and collect power charges. The situation is going for the better little by little. However, efforts to build or expand power transmission lines and increase power supply that need some investment in plant and equipment are still in the planning stage for lack of funds.
(4) Financing capacity
As described above, KESC is required to improve itself financially. One such attempt is the government's 34-billion-rupee collective plan to restructure KESC financially. KESC also established an assistance program for 225 million dollars with the Asian Development Bank (ADB), which provided the first installment of 150 million dollars. This fund is to be used for restructuring KESC financially and privatize it in the future.
Thus, KESC has been working hard to improve itself financially with the assistance of the Pakistani Government and other capital funds. With its debts guaranteed by the Pakistani Government, KESC has been purchasing fuels for power generation and other electric power. This style will continue and fund-raising will presumably be proceeded with under the government's guarantee.
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(5) Human resources
KESC has a work force of 12,499 as of the end of June, 1999. Of which 11,502 are shop-floor personnel working at power stations and other facilities. As described above, all executives of the power stations are engineers, and the head office personnel, except for the president and personnel higher in rank, are members with experience in managing a power station. In carrying out the project, KESC has enough human resources to set up a unit of project resources with personnel from within KESC.
(6) Executive organization
KESC's management system is as described in (2). If the project is set to be launched, KESC is scheduled to organize a project team to tackle concrete plans for funds, schedules, transportation and installation of equipment, and other operations.
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2.4 Project situation and specifications of equipment and facilities after replacing the existing Gas Turbines with advanced ones
2.4.1 System and major equipment
In the modification of the KORANGI GT PS and the SITE GT PS surveyed, the collective replacement of generator, supply/exhaust ducts, auxiliary equipment for gas turbines and other equipment, not only the replacement of the gas turbines alone, will display the performance 100% and maximize the output and efficiency after the replacement.
However, as a result of field survey of the power stations, it becomes clear that power station personnel basically intended to use all usable generators and other existing equipment. Regarding the generators, it is concluded that the generators can be restored almost to their initial performance and be reused if their armature windings (stator coil) and the field windings (rotor coil) are rewound. Therefore, following two cases are selected and studied:
Case 1: Replacing all the gas turbines, generators, and peripheral auxiliary equipment.
Case 2: Replacing the gas turbines and reusing the existing generators with their coils rewound. The peripheral auxiliary equipment will basically be replaced.
(1) System configuration
The above two cases were studied in detail.
1) Case 1
F5 type gas turbines are replaced with ones of the latest type. Generators are also replaced with ones designed for the latest model. The air inlet / exhaust plenum and connecting ducts, auxiliary equipment for the gas turbines, and other equipment is also replaced with new ones. The existing inlet house, inlet duct and exhaust gas stack will be reused.
2) Case 2
F5 type gas turbines are replaced with ones of the latest type. For the generators, the existing ones are reused, so that their stator coil and rotor coil is rewound. For the auxiliary equipment for the gas turbines, the units that are not considered to be able to withstand next 20 years of operation are replaced.
(2) Performance
Fig. 2.4-1 and 2.4-2 show the atmospheric temperature characteristics of the output and thermal efficiency as the expected performance after the modification. The figures
2-122
also indicate the design characteristics of the existing equipment and its current operation status. Fig. 2.4-3 and 2.4-4 show the heat balance diagram at an atmospheric temperature of 35°C.
Case 1 involves replacing the gas turbines and main equipment for the generators, as well as peripheral auxiliary equipment, with new ones. Their performance can therefore be equivalent to that of the equipment to be installed. F5 type gas turbine is replaced with ones of the latest type, resulting in the gas turbine outputs increasing to 2,950kW on a design-value basis (at an atmospheric temperature of 15°C) and to 3,100kW (at an atmospheric temperature of 35°C). The generators are also designed to these gas turbine outputs, which make it possible to come with up the optimal design. This achieves the greatest possible effects not only in output but in efficiency as well.
In Case 2, the generators are subjected to the rewinding of the stator and rotor. They can therefore be almost to their design performance. However, this involves reusing generators for F5 type gas turbines and having relatively small capacities, thus resulting in a mismatch with the output of the latest-model gas turbine. In actual operation, the gas turbine output is matched to the generator capacity, so that the gas turbines need to be operated on a partial load. The output thus obtained is inhibited to the capacity of the reused generators, becoming identical with the design value before the replacement. No rise in the output is therefore expected. Plant efficiency will be lower than in Case 1, although larger than before the replacement, because the gas turbines will be operated on a partial load.
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DES
IGN
OU
TPU
T (k
W)
30,000
F5(PG5341)
Latest (Case 1)
25,000
Latest (Case 2)20,000
FUEL:NATURAL GAS ISO CONDITION
15,000
COMPRESSOR INLET TEMPERATURE (°C)
OPERATING STATUS • SITE GT PS
(Oct. 15, 2000)O KORANGI GT PS
(Oct. 16, 2000)
Fig. 2.4-1 Comparison of Base Load Design Curve for Outputbetween Existing F5 Gas Turbine and Latest Gas Turbine
>oUJOLULLLD
<CLLUII-oCOLUQ
Latest (Case 1
Latest (Case 2)
F5(PG5341)
FUEL:NATURAL GAS ISO CONDITION
OPERATING STATUS (1999-2000 Annual Average)
- . - - SITE GT PS ---------- KORANGI GTPS
COMPRESSOR INLET TEMPERATURE (°C)
Fig.2.4-2 Comparison of Base Load Design Curve for Efficiencybetween Existing F5 Gas Turbine and Latest Gas Turbine
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Performance
Gas Turbine Output 23,450 kW
Thermal Efficiency : 31.1 %
Fuel Heating Value : 46,381 kJ/kg
CASE 1
Conditions
Ambient Temperature : 35 °C Relative Humidity : 60 %
Atmospheric Pressure: 1,013kPa
Fig. 2.4-3 Heat Balance Diagram of Latest Gas Turbine Generation Facility (Case 1)
5,346 kg/h
Stack
Generator
20.360 kW
Gas Turbine
Performance
Gas Turbine Output 20,360 kW
Thermal Efficiency : 29.3 %
Fuel Heating Value : 46,381 kJ/kg
CASE 2
Conditions
Ambient Temperature :
Relative Humidity
Atmospheric Pressure:
35 °C
60 %
1,013kPa
Fig. 2.4-4 Heat Balance Diagram of Latest Gas Turbine Generation Facility (Case 2)
-2-125
(3) Operation
The existing gas turbine power generation units are started at 17:00 or 18:00 in the evening and stopped around 22:00, thus conducting a typical peak-response operation.
The power supply in Karachi city is chronically insufficient. Not only planned outages but also unplanned outages due to unclear causes are frequent. Extending the operating time of the gas turbine power stations will help alleviate the power shortage. However, in reality, KESC cannot pay the price of the natural gas, which is the fuel for electricity, and are subjected to gas supply restrictions. They secure the current supply quantity only in response to the central government's instructions to the gas companies.Aff-or tho mnHifinotinn tho ctatlnnc \a/II increase its thermal efficiency, thus saving fuelexpenses. The details are given in Chapter 3. Estimating the saving of the fuel expenses after the replacement of the gas turbines on the basis of the operation status in 1999 and 2000 indicates that savings of 30-35% or so can be made. However, considering the chronic power shortage, controls on operating time due to the restrictions on fuel supply, and a rise in power demand due to future economic growth, the extension of the operating time of the gas turbine power stations will be inevitable if only the issue of the fuel supply is resolved.
The ideal scenario is that, as shown in Fig. 2.4-5, the DSS will be used as an operation method to respond to the daytime power demand. This is expected to alleviate the planned outage during the daytime. However, if the operating time is to be extended for the equipment without modification, emissions of carbon dioxide, which causes a greenhouse gas, will increase further. It is imperative to replace the gas turbines with ones of the latest model soon. (The outputs indicated in Fig. 2.4-5 are indicated for Case 1 where the DSS is used after the replacement. In Case 2, the outputs will be lower than in Case 1 but the operation method will be identical.)
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Full Load
( 23.46 MW )
24:00
Shut downTime ( hr )Start up
24:00
Fig. 2.4-5 Desirable Operation Pattern of Gas Turbine after Replacing
Note; (1) GT full load output at 35°C of ambient temperature for case 1.
GT output for case 2 is reduced to the current value due to re-use of existing generator.
(2) GT output varies with the ambient temperature.
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(4) Specifications and details of power plants
Results of the specification study of power plants in each case are shown below.
1) Gas turbine equipment
The existing gas turbine equipment will be replaced with high-efficiency units of the latest model in both Case 1 and 2. An example of the specifications and performance of the latest gas turbine are shown in Table 2.4-1, 2.4-2 and in Fig. 2.4-6, 2.4-7.
The output and efficiency of a gas turbine is related to the reductions in carbon dioxide based on the COM. The gas turbines to be replaced should desirably be equal or superior to the performance indicated in the figures. Any performance lower than that is expected to fail in the carbon dioxide-reducing effect to be described later.
Fig. 2.4-8 shows the scope of the gas turbine equipment to be replaced. Here are the details:
(D Equipment to be replaced
a. Gas turbine package
b. Reduction gears and load couplings
c. Air inlet and exhaust plenum and connection ducts between the air inlet and exhaust ducts
d. Controlling board for gas turbines
e. Off-base radiators
(2) Equipment to be reused
a. Air inlet house and duct
b. Exhaust duct
c. Foundation
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Table 2.4-1 Summary Specifications of Latest Gas Turbine
~ ~~ —Model
Item ~~ ~~ „Latest Gas Turbine
Gas Turbine
Type Heavy Duty
Cycle Simple Cycle
Number of Shafts 1
Rated Speed (min ^ 7,280
Air Compressor
Number of Stages 17
Type Axial Flow
Casing Split Horizontal
Rotor Built-up
Turbine
Number of Stages 3
Type Impulse
Casing Split Horizontal
Rotor Built-up
Combustor
Type Reverse Flow
Number of Combustors 10
Nozzle per Combustor 1
BearingNumber of Radial Type Bearings 2
Number of Thrust Type Bearings 1
Starting
Equipment
Diesel Engine (HP) 710
Electric Motor (kW) 450
Table 2.4-2 Estimated Performance of Latest Gas Turbine
Fuel Natural Gas Diesel Oil
Output (kW) 26,900 26,330
Heat rate (kcal/kW-hr) 2,608 2,634
Inlet Air Flow (kg/sec) 88 88
Exhaust Temperature (°C) 550 550
* ISO Condition
2-129
2-130
IT
1
Fig. 2.4-6 Latest Gas Turbine Outline
1 5 r n
2-131
r
L
<NOTES)1. LIFTING WIRE ARE NOTFURNISHED BY HITACHI LTD,
DIMENSIONS =11580X3570X4000 mm
GROSS WEIGHT'SCL.0Q0.kBDVN. [It Hosoda) OS* 0 4■0 B
DM. (, llatanabe OS10 4•D B. .
sm DUG.ZONE REVISIONS DATE ?EVD. wd, st
m. MIR. r£,MF,
Rt(UL
ttt "R~ l till
PROJECTION TITLE
N-T-S
Hitachi.Ltd.Tokyo Japan
GAS TURBINE LIFTING ARRANGEMENT
HITACHI WORKS DWG. KL
Fig. 2.4-7 Latest Gas Turbine Lifting Arrangement
2) Fuel supply system
a) Gas compressors
A plan for modification of the gas compressors when replacing the existing gas turbines with high-efficiency ones of the latest model is shown below. The plan for the gas compressors is described for each power station, because the conditions vary according to this power station.
(i) KORANGI GT PS
i) Reason for modification
In response to the replacement of the gas turbines with ones of the last model, the supply pressure of the natural gas fuel must be increased. To that end, the existing gas compressors will be modified. The discharge pressure of the gas compressors will be as follows before and after the modification:
• Before modification: 230psig -After modification: 340psig
These figures represent the necessary supply pressure (320psig) of the gas turbines plus the pressure loss (20 psig) from the gas compressor outlet to the P2 pressure measuring point at the gas turbine inlet. The specifications of the gas compressors after the modification are shown in Table 2.4-3, the flow sheet in Fig.2.4-9, and the performance curve in Fig. 2.4-10. Fig. 2.4-11 shows the number of gas turbines that can be operated due to the change in the suction pressure of the gas compressors after the modification.
According to the trend of past data shown in Table 2.2-15 in clause 2.2.1 representative log sheet, the suction pressure, which has an influence on the performance of gas compressors, is determined to be 50 to 150 psig in our plan. The scope of modification on the gas compressors changes with this range, and necessary minimum modification was conducted. If suction pressure is lower than 50 psig, one unit of the gas compressor cannot develop the required capacity for the one of gas turbine. And if suction pressure is lower than 40 psig, mechanical strength will be operated exceeding its capacity. Further, if suction pressure is higher than 150 psig, mechanical strength will be operated also exceeding its capacity. For the gas compressor to develop the required capacity by operation within its mechanical strength, a large-scale renovation, including the frame, is indispensable.
ii) Modification range of the existing gas compressors
The pressure-proof parts will basically be renewed in response to the rise in discharge pressure. The main modification parts are the first and second stage cylinder assemblies, pressure control valves and vessels after second stage cylinder. Other instruments and oiling devices are also expected to undergo secular deterioration and must be renewed. Spare parts are recommended for major overhauls after the modification.
-2-133-
The details of the modification and diversion parts are shown in Table 2.4-4 and Figs. 2.4-12 to 2.4-20. Modification parts are the same as for each power station.
iii) Cooling system
Due to the shortage of cooling water for the gas cooler, oil cooler and cylinder of the gas compressors, there is demand for change to a high-performance cooling tower type closed cooling water system. Such a system is therefore proposed as an optional basis.
-2-134-
Table 2.4-3 Gas Compressor Specification after Modification (KORANGI GT PS)
Item UnitAdapted to F5
(Original design)Adapted to Latest (After modification)
Number of units — 4
Type — BTD-ICC
Manufacturing number — 76A1101501, 276A1101601, 2
1st stage suction pressure psig 30-150 50—150
2nd stage discharge pressure psig 230 340
Gas capacity kg/h7,500 (at 30psig)
30,000 (at ISOpsig)5,950 (at SOpsig)
15,750 (at ISOpsig)
Suction temperature °C 15—45 15—45
Gas component
mol %
ch4 94.42 94.36
CzHs 1.05 0.96
CsHb 0.28 0.28
C4H10 0.12 0.15
C5H12 0.05
n2 3.89 4.1
OO
0.02 0.66
02 0.17
h2 0.17 0.25
Molar weight — 16.85 16.95
Cylinder lubrication — Yes
Cylinder diameterx unit 1st stage (mm) #615X1 #485X1
2nd stage (mm) #466X1 #355X1
Piston rod diameter mm #90
Stroke mm 315
Speed min"1 369
Driver type — Induction motor
Output power of main motor kW 1100
Cooling water temperature 0 F(°C) 84-120(28.9-48.9)
Power supplyMain motor
Auxiliary motorInstrument
3300 V 50 Hz AC380 V 50 Hz AC110 V 50 Hz AC
2-135
I 2 3 4
CD
ZJ SEPARATOR
Z SYM60LS;
Tt: thermometer
PI : PRESSut?& GAUGE
Tha ; temperature suhtch
PLL : OIL PRESSUR& SWITCH (shut DounJ)
pip ; OIL pR&LSUftE SWITCH(ALARM)
LG • LEVEL <5AL<y&
F(p • S/ Gfi T PLOU)
OS ; 0M STRAW£R
op : oil f/ltep
Z. O ; PfOUK/TAO O/J GAU&E
O ; Mounted J-ocally
NO. REVISIONS DATE REVISED CHECKED
A*7 ADDLO TNtRMOHLTEBS i SATHY YAIV&J. '76-09- 29 C.tjAoskiX^) iLpA/tPo
i
|
DT\ DRAIN TRAP
SEPARATOR CK//TH DEM/STeR)
FOR REFERENCE
TUB KARACHI ELECTRIC SUPPLY COR PoRAT/ L/M/TEDmorale ( t<?wa! s-as turbime pou/er stat/om
YOfJSULTA/JTS : F/OVTMER CODS ULTIMO FA/GtRSBRSTHIS DRAWING IS THE PROPERTY OF HITACHI. THE DATA. INFORMATION OR ANY PART OF THE DRAWING HEREON SHALL NOT BE COPIED. REPRODUCED LOANED OR USED FOP ANY PURPOSE WITHOUT WRITTEN PERMISSION FROM HITACHI.
J I I I I I 1 i-----1----L l l I I 1 I—JL.
S/RC&
ROTE 3. /T IS Pass/gJ-S THAT THE / fj T 6 R COOLER
IS MOHfJTEO upoij me- MACH/RE-, the /UTER
CCOEER CPShJCt CoRTA/rJS JD-SRUSBER ,
ZS-SEPARATOR bHQ 26 - 6RUBBER .
NAME CODE SPEC COOEUNTCOOE
OWN. A/, /)tASL.frP.- (TaU f, THIRD0 ANG. PROJ.
i -SCALE
APPO. JW. 9 'll hrs
# Hitachi, Ltd.Tokyo Japan
date GUST COOE
J I i J l.MFC NO OR EST NO
I 1.1 1 1 .J I—I—L.
REF DWG NO
nTLE <5-/4 J COMPRESSOR
fioR ctAS TciRBiA/B
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FLOUJ D/ACtRAHT SUO? UR A WORKS DWG NO
A
m
2 I 3
Fig.2.4-9 Flow Diagram of Modified Gas Compressor
2-136-137
Table 2.4-4 (1) Scope of Diverted Parts and Modified Parts (KORANGI GT PS)1) Main unit
Classification Parts name 1 unit 4 units Diverted Renewed
Content of modification Remarks
Mainmotor
Main motor 1set 4sets o Diverted after overhaul
Coupling guard 1set 4sets o
Frame
Frame 1set 4sets oFrame top cover 3pcs 12pcs oAir breather 1set 4sets oFrame side cover(1) 1set 4sets oFrame side cover(2) 1set 4sets oMain bearing cap 2pcs 8 pcs oMain bearing (1) 1set 4sets o Replaced with new
part the same as existing one.Main bearing (2) 1set 4sets o
Crank shaft 1set 4sets oCoupling 1set 4sets o
Crossguide,crosshead,connecting rod
Connecting rod 2sets 8sets oCap bolt, nut 4sets 16set
s oLarge end bearing 2sets 8sets o Replaced with new
part the same as existing one.Small end bearing 2pcs 8 pcs o
Cross guide 2sets 8sets oSupport 2sets 8sets oCross head, Cross shoe 2sets 8sets oCross pin 2 pcs 8pcs oCross bearing 4pcs 16 pcs o Replaced with new
part the same as existing one.
1ststagecylinder
CylinderIncluding the following
■ Outer cylinder cover inner cylinder cover cylinder liner jacket cover s-valve cover s-valve cage d-valve cover d-valve cage cylinder support distance piece
1set 4sets o
Will be renewed by changing cylinder size and proof pressure according to increased discharge pressure.
2ndstagecylinder
CylinderIncluding the following
■ Outer cylinder cover inner cylinder cover cylinder liner jacket cover s-valve cover s-valve cage d-valve cover d-valve cage cylinder support distance piece
1set 4sets o
Will be renewed by changing cylinder size and proof pressure according to increased discharge pressure.
-2-139
Classification Parts name 1 unit 4 units Diverted Renewed
Content of modification Remarks
1 st stage piston
Piston 1set 4sets o
According to the change in cylinder diameter, related parts will be renewed.
Piston ring 2pcs 8pcs oRider ring 2pcs 8pcs oPiston rod 1set 4sets o
2ndstagepiston
Piston 1set 4sets oPiston ring 4 pcs 16pcs oRider ring 2pcs 8pcs oPiston rod 1set 4sets o
1st stagecylindervalvesuctionunloader
Suction valve assay 6sets 24sets oDischarge valve assay 6sets 24sets oS-unloader assay 6sets 24sets o
2nd stagecylindervalvesuctionunloader
Suction valve assay 4sets 16sets oDischarge valve assay 4sets 16sets oS-unloader assay 4sets 16sets oPacking case 4sets 16sets oStuffing box 2sets 8sets o
Oilscraperring
Rod packing 4 sets 16sets oReplaced with new parts that is the same as existing one.
Oil scraper ring 4sets 16sets oWave spring 6 pcs 24 pcs oHolder 6pcs 24pcs o
1st &2ndstageglandpacking
Rod packing 10sets 40sets oRod packing made of PTFE is aoplied which shows more excellent initial fit and less corrodes the packing box than conventional metal rod packing.
Pressure breaker 2 pcs 8pcs oPressure breaker box 4pcs 16pcs oPacking box 10pcs 40pcs oGland cover 2pcs 8 pcs oCover 2 pcs 8 pcs o
Gasket Gasket 1set 4sets oFor parts replacement of compressor main unit.
Gascooler
Inter cooler 1set 4sets o Renewed due to the change in specificationAfter cooler 1set 4sets o
For inter cooler (drain trap; 1, by-pass valve; 2,strainer: 1, other piping valve: 1)
1set 4sets o
Renewed bychanging proofpressureaccording toincreaseddischargepressure
2-140
Classification Parts name 1 unit 4 units Diverted Renewed
Content of modification Remarks
Separator
1st. stage suction separator 1set 4sets o
Diverted after subjected to pressureand air tightening test at site to see that there will be no problem
For 1st. stage suction separator (drain trap; 1, by-pass valve;2,strainer: 1, other piping valve: 1)
1set 4sets oRenewed by changing proof pressure according to increased discharge pressure
Snubber
1st. stage suction separator 1set 4sets o renewed due to the change in
cylinder size
2nd. stage suction separator Iset 4sets o
Renewed by changing proofpressure according to increased discharge pressure
Receiver
Receiver 1set oRenewed by changing proof pressure according to increased discharge pressure
For Receiver (drain trap; 1, by-pass valve;2,strainer: 1, other piping valve: 1)
1set o
LubricatorLubricator (Include bracket, sprocket, oil seal)
1set 4sets o Renewed due to aged deterioration
Frame lube unit
Pump, motor, piping valve, oil filter (1), oil filter (2), tank, level gauge
1set 4sets o Renewed due to aged deterioration
Pipingvalve
Check valve 2sets Ssets oRenewed by changing proof pressure according to increased discharge pressure
Main discharge valve 8B 1pcs 4pcs oValve for receiver 8B 2 pcs o
Valve for control valve 6B 2 pcs oControl valve 1set o Replaced with new one as a whole.
Pipingmaterial
Gas piping, cylinder and rod packing lubrication piping, frame lubrication piping, vent piping
4sets oExisting piping is diverted as possible, using spacers, short pipes, etc
Only the tie-in of renovated or renewed parts is renewed.Other piping is diverted.
Instrument
Pressure gauge, pressure switch, temperature gauge, temperature switch, flow sight
4sets oRenewed by changing proof pressure according to increased discharge pressure
Gaugestand
Gauge stand 1set 4sets o Only the replacement of measuring instruments is performed
Safetyvalve
For 2nd stage ditch. 1set 4sets o Renewed by changing proof pressure according to increased dischargeFor receiver 1set o
Table 2.4-4 (3) Scope of Diverted Parts and Modified Parts (KORANGI GT PS)3) Option
Classification Parts name 1 unit 4 units Diverted Renewe
d Content of modification
Radiator Radiator 1set Ssets — . oAs for the customer’s request, coolingwater and lubrication oil cooling system will be changed the cooling air system.
2-141
Table 2.4-4 (2) Scope of Diverted Parts and Modified Parts (KORANGI GT PS)
2) Spare parts
Parts name For 1 unit For 4 units Spare parts
1st stage suction 4sets 16sets 8sets
1 Cylinder valve assay 1st stage discharge2nd stage suction
4sets4sets
16sets16sets
8sets8sets
2nd stage discharge 4sets 16sets 8sets
2 Valve plate 1 st stage2nd stage
8pcs8pcs
32pcs32pcs
96pcs96pcs
3 Valve spring 1 st stage2nd stage
1set1set
4sets4sets
12sets12sets
4 Piston ring 1 st stage2nd stage
2pcs4pcs
8 pcs16 pcs
24pcs48pcs
5 Rider ring 1 st stage2nd stage
2 pcs 2pcs
8 pcs8 pcs
24pcs24pcs
6 Rod packing 14sets 56sets 168sets
7 Pressure breaker 2pcs 8pcs 24pcs
8 Oil scraper ring 8sets 32sets 96sets
9 Main bearing (1) 1set 4sets 12sets
10 Main bearing (2) 1set 4sets 12sets
11 Large end bearing 2sets 8sets 24sets
12 Small end bearing 2pcs 8 pcs 24pcs
13 Cross bearing 4pcs 16 pcs 48pcs
14 Gasket for parts replacement of compressor main unit 1set 4sets 12sets
15 Spare parts for radiator — — —
16 Tube nest for inter cooler (With spare gasket) 1set 4sets 1set
17 Tube nest for after cooler (With spare gasket) 1set 4sets 1set
18 Air breather 1set 4sets 1set
19 Crank shaft 1pcs 4 pcs 1pcs
20 Coupling 1set 4sets 1set
21 Connecting rod 2sets 8sets 2 sets
22 Cross head, Cross shoe *1 2sets 8sets 2sets
23 Spare parts for Oil pump 1set 4sets 4sets
24 Element for lubricator 1set 4sets 4sets
25 Spare parts for control valve 1set 4sets 4sets
Note: The quantity may be changed in detail design.*1 One upper cross head shoe and one lower crosshead shoe make a pair.
2-142
2 3
REVISIONS
: replacement parts
THIS DRAWING IS THE PROPERTY OF HITACHI. THE DATA. INFORMATION OR ANY PART OF THE DRAWING HEREON SHALL NOT 8E COPIED. REPRODUCED. LOANED OR USED FOR ANY PURPOSE
THIRD ANG. PROJ.
FRAME /ASSEMBLY d)Fig. 2.4-12 Frame Assembly (1)
Tokyo Japan
I.1
2 3 4
J NO. j REVISIONS DATE REVISED CHECKEDj
J- ____' 707t,t
tnt fit5
Fig. 2.4-13 Frame Assembly (2)
THIS DRAWING IS THE PROPERTY OF HITACHI. THE DATA. IN- 'V- ANY PART OF THEDRAWING HEREON SHALL NOT BE COPIED. REPRODUCED. LOANED OR USED FOR ANY PURPOSE WITHOUT WRITTEN PERMISSION FROM HITACHI.
a X , iTJZdg NAME CODE CUST COOE MF&.NO. OR EST NO. RET. DWa NO.
rs -12-17 THIRD 315s
fM^JL •*9- z 't
AIMG. PROJ.
X2 UTSfMHE /issf^lY (?)
Hitachi, Ltd.Tokyo Japan
CD
<
4
to4-^CD
Fig. 2.4-14 1st Stage Cylinder Assembly
_ 0 0 0 0 0
[QUIER CYLINDER COVEFka I CYLINDER AgY•n. Afi-_?o_-gL THIRD
IAVwjlMaaa ^ (m^Hitachi, Ltd.' Tokyo Japan
2ND STAGE. CYLINDER assembly
+*JO*U*A WORKS DWft
Fig. 2.4-15 2nd Stage Cylinder Assembly
$30*
3
WO. REVISIONS | DATE revised j checked
a. cvifi Vt>J (tit iicl ) !*' <>>'? /AtAw
rL.iftJ 'Hit (>!*}* dect»*a'1 , , ..
Fig. 2.4-17 1st Stage Suction Valve Unloader
replacement parts
Z. . j7J/>
•fec ro Ef-T o^Tcnctf «, of
tmiS^ofawino THC P»0»E»TV Or HITACHI THE DATA. «rO««*AT • HALL HOT et CO#PEAMI3SIOH f HOW
ORAWINti HCArtOH SHALL HOT #t COF'ICO. ACPROCA/CCG. LOAHtO OH USED FO* AHT PUAAOH
9-fo?a/>tAi
# Hitachi, Ltd.'"r Tokyo Japan
suctionVALVE (JLNLPAPER
(momm »OAKA p»a #o
£
b
Fig. 2.4-17 2nd Stage Suction Valve Unloader
replacement parts
/e>3-—THIRD
SUCTl ON
l/ALVE UNI PAPER
2-149
i 2 3 4
NO. REVISIONS DATE REVISED CHECKED
4> rUAA/tfD 7»l mU TtATt rfuckHIX fZB-Pt-’zj
-h*-
~/29*~
-/SS*-
m
IWfe : replacement parts
<
'z/cP-ESk
-220*-?%-
Fig. 2.4-18 1 st & 2nd Stage Discharge Valve Assembly
T T
THIS DRAWING IS THE PROPERTY. OF HITACHI. THE DATA. INFORMATION OR ANY PART OF THE DRAWING HEREON SHALL NOT BE COPIED. REPRODUCED. LOANED OR USED FOR ANY PURPOSE WITHOUT WRITTEN PERMISSION FROM HITACHI.
If R£,CrC&ffl /, I
4| NAME CODE mfgno. or est.no. REF. DWG. NO.
THIRD fs7 sr/tff * 2/jp
^KoYAstUt ANG. PROU.
l'T,S.
discharge
VALVE ASSEMBLY
# Hitachi, Ltd.Tokyo Japan
TSUOUURA WORKS DWG NO. REV.
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I 2
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ins*
-
3 4
NO. REVISIONS DATE REVISED CHECKED
m
Fig. 2.4-19 Oil Separator Ring Assembly
fSBIftl : replacement parts
THIS DRAWING IS THE PROPERTY OF HITACHI. THE DATA. INFORMATION OR ANY PART OF THE DRAWING HEREON SHALL NOT BE COPIED. REPRODUCED. LOANED OR USED FOR ANY PURPOSE
THIRDANG. PROJ.
O/L SCKATE-R
ASSEMBLY
<
i 4
I 2 3 4
NO. REVISIONS DATE REVISED CHECKED
Wfitgl : replacement parts
•miS DRAWING IS THE PROPERTY OF HITACHI. THE DATA. INFORMATION OR ANY PART OF THE DRAWING HEREON SHALL NOT BE COPIED. REPRODUCED. LOANED OR USED FOR ANY PURPOSE WITHOUT WRITTEN PERMISSION FROM HITACHI.
'£L-Q)nf A , 7SJ2-.
Fig. 2.4-20 1st & 2nd Stage Rod Packing Assembly
n.sHi&m - 7d - /? - /? THIRDf-koY/uta^ tf'O/"O? ANG^PROJ.
SCALE
Appa t&jLJL.
Hitachi, Ltd.Tokyo Japan
DATE CUST.COOC I MFO.NO OR EST.NO. REF. 0*6. NO
/ST STA*£ * ?»*>
7SUCMURA WOfWS 0*6 NO.
(ii) SITE GT PS
i) Reason for modification
In response to the replacement of the gas turbines with ones of the latest model, the supply pressure of the natural gas fuel must be increased. To that end, the existing gas compressors will be modified.
The discharge pressure of the gas compressors will be as follows before and after the modification:
•Before modification: 230 psig -After modification: 340 psig
These figures represent the necessary supply pressure (320 psig) of the gas turbines plug the pressure loss (20psig) from the gas compressor outlet to the P2 pressure measuring point at the gas turbine inlet. The specifications of the gas compressors after the modification are shown in Table 2.4-5, the flow sheet in Fig.2.4-21, and the performance curve in Fig. 2.4-22. Fig. 2.4-23 shows the number of the gas turbines that can be operated due to the change in the suction pressure of the gas compressors after the modification.
According to the trend of past data shown in Table 2.2-32 in clause 2.2.2 representative log sheet, the suction pressure which has an influence on the performance of gas compressors, is determined to be 50 to 150 psig in our plan. The scope of modification on the gas compressors changes with this range, and we made a plan to make necessary minimum modification. If suction pressure is lower than 50 psig, one unit of the gas compressor cannot develop the required capacity for the one of gas turbine. And if suction pressure is lower than 40 psig, mechanical strength will be operated exceeding its capacity. Further, if suction pressure is higher than 150 psig, mechanical strength will be operated also exceeding its capacity. For the gas compressor to develop the required capacity by operation within its mechanical strength, a large-scale renovation, including the frame, is indispensable.
ii) Modification range of the existing gas compressors
In response to the rise in discharge pressure, the pressure-proof parts are basically renewed. The main modification parts will be the first and second stage cylinder assemblies, pressure control valves, the vessels more downstream than and the second stage cylinder. Other instruments and oiling devices and radiator may also undergo secular deterioration and must be renewed. Spares are recommended for major overhauls after the modification.
The details of modification and diversion parts are shown in Table 2.4-6 and Fig.2.4-12 to 2.4-20. The modification parts are the same as for each power station.
-2-152
b) Fuel gas system
The equipment described below needs consideration to change.
(D Gas flow meter
Gas flow meter has long been in a non-functioning condition. This is estimated to be due to a breakdown of the operation unit. Gas flow meter renewal is imperative in monitoring dirt in air compressors and other secular deterioration, thus ensuring the sound and economical operation of gas turbine equipment.
(D Pressure transmitter
The pressure transmitters have long been left uncalibrated and unadjusted. They have therefore declined in reliability as instruments. We believe it imperative to renew these units too.
2-153
Table 2.4-5 Gas Compressor Specification after Modification
Item UnitAdapted to F5
(Original design)
Adapted to Latest
(After modification)
Number of units — 5
Type — BTD-ICC
Manufacturing number — 78A1102901 — 05
1st stage suction pressure psig 30-200 50-150
2nd stage discharge pressure
psig 220 340
Gas capacity kg/n7,500 (at 30psig)
30,000 (at 150psig)
5,700 (at SOpsig)
15,750 (at 150psig)
Suction temperature °C 9-29.4
0CD1OCM
Gas component
mol %
ch4 94.42 94.36
C2H6 1.05 0.96X0
0.28 0.28
Xd
0.12 0.15
C5H12 0.05
N2 3.89 3.98-4.10
CO2 0.02 0.02-0.06
02 0.17 0.17-1.00
H2 0.17 0.25
Molar weight — 16.85 16.79
Cylinder lubrication — Yes
Cylinder diameterx unit 1st stage (mm) 0615X1 0485X1
2nd stage (mm) 0466X1 0355X1
Piston rod diameter mm 090
Stroke mm 315
Speed min"1 369
Driver type — Induction motor
Output power of main motor kW 1,100
Cooling water temperatureMain motor
Auxiliary motor
Instrument
3300 V 50 Hz AC
380 V 50 Hz AC
110 V 50 Hz AC
2-154
2
/A'STRUMENT AIR
AonAd. r’-kssitre.(.WITH 'DBMISTET^
I-------
n & n !-:PRESSURE GAUGE
THERMO METER
v/lTCTEMPERATURE .5
MOTOR SWITCH
OIL PRESSURE SWITCH
OIL PRESSURE SWITCH
SIGHT FLOW
DRAIN
SAFETY VALVEPIECE GEAR PUMP
WATER PUMP
LEVEL GAUGE3 WAY /ALVE
MOTOR
CHECK VALVE
OIL FILTERS.S/VUBBfK
OIL STRAINER
FLOW SWITCH
mount bo ON
THE KARACHI ELECTRIC SUPPLY CORPORATION LIMITED
S. I.T.E. GAS TURBINE POWER STATION
CONSULTANTS : F1CHTTJER, CONSULTING ENGINEERS
—tx]|——{XL
—© ©“ THIS CSAV.-|KG"I5" "THE FSC'l^TT 'or HITACHI' THE DATA. INFOR'.’.A TICN C= A NY PART C-F . ORAWiNG HEREON SMALL NOT BE COPIED REPRODUCED LOANED OR USED FOR ANY PURPC.
RADIATOR. FcR- W/ATBR.LUBRICATOR IIOOKWBTD-ifO EdSrOMTPESSG'RTHIRD
ANG. PROJ.( DR! UBN BY CRANK SMART AND >
FLOW DIAGRAM
FOR REFERENCE Tokyo Japan
Fig. 2.4-21 Flow Diagram of Modified Gas Compressor2-155-156
Table 2.4-6 (1) Scope of Diverted Parts and Modified Parts (SITE GT PS)
1) Main equipment
Classification Parts name 1 unit 5 units Diverted Renewed
Content of modification Remarks
Mainmotor
Main motor 1set 1set o Diverted after overhaul
Coupling guard 1set 5sets o
Frame
Frame 1set 5sets oFrame top cover 3pcs 15pcs oAir breather 1set 5sets oFrame side cover(1) 1set 5sets oFrame side cover(2) 1set Ssets oMain bearing cap 2 pcs lOpcs oMain bearing (1) 1set Ssets o Replaced with new part
the same as existing oneMain bearing (2) 1set Ssets oCrank shaft 1set Ssets oCoupling 1set Ssets o
Crossguide,crosshead,connect!ng rod
Connecting rod 2sets 10sets oCap bolt, nut 4sets 16sets oLarge end bearing 2sets 10sets o Replaced with new part
the same as existing oneSmall end bearing 2pcs 10pcs oCross guide 2sets 10sets oSupport 2sets 10sets oCross head, Cross shoe 2sets 10sets oCross pin 2 pcs 10pcs oCross bearing 4 pcs 20pcs o Replaced with new part
the same as existing one
1 st stage cylinder
CylinderIncluding the following Outer cylinder cover inner cylinder cover cylinder liner jacket cover s-valve cover s-valve cage d-valve cover d-valve cage cylinder support distance piece
1set Ssets o
Will be renewed by changing cylinder size and proof pressure according to increased discharge pressure.
2ndstagecylinder
CylinderIncluding the following ■ outer cylinder cover inner cylinder cover cylinder liner jacket cover s-valve cover s-valve cage d-valve cover d-valve cage cylinder support distance piece
1set Ssets o
Will be renewed by changing cylinder size and proof pressure according to increased discharge pressure.
2-158-
Ciassification Parts name 1 unit 5 units Diverted Renewed
Content of modification Remarks
Piston 1set 5sets o
According to the change in cylinder diameter, related parts will be renewed.
1 st stage piston
Piston ring 2 pcs 10pcs oRider ring 2pcs 10pcs oPiston rod 1set 5sets o
2ndstagepiston
Piston 1set 5sets oPiston ring 4pcs 20pcs oRider ring 2pcs 10pcs oPiston rod Iset 5sets o
1st stagecylindervalvesuctionunloader
Suction valve assay 6sets 30sets oDischarge valve assay 6sets 30sets oS-unloader assay 6 sets 30sets o
2nd stagecylindervalvesuctionunloader
Suction valve assay 4sets 20sets oDischarge valve assay 4sets 20sets oS-unloader assay 4sets 20sets o
Oilscraperring
Packing case 4sets 20sets oStuffing box 2sets 10sets oRod packing 4sets 20sets o Replaced with new
parts that is the same as existing one.
Oil scraper ring 2sets 10sets oWave spring 6pcs 30pcs oHolder 6pcs 30pcs o
1st & 2nd stage gland packing
Rod packing 10sets 50sets oRod packing made of PTFE is applied, which shows more excellent initial fit and less corrodes the packing box than conventional metal rod packing.
Pressure breaker 2pcs 10pcs oPressure breaker box 4pcs 20pcs oPacking box 10pcs 50pcs oGland cover 2pcs 10pcs oCover 2pcs 10pcs o
Gasket Gasket 1set 5sets oFor parts replacement of compressor main unit.
Inter cooler 1set 5sets o Renewed due to the change in specification
Gascooler
L _j
After cooler 1set 5sets oFor inter cooler (drain trap; 1, by-pass valve; 2,strainer: 1, other piping valve: 1)
1set 5sets o
Renewed bychanging proofpressureaccording toincreaseddischargepressure
-2-159-
Classification Parts name 1 unit 5 units Diverted Renewed
Separator
1st. stage suction separator 1set 5sets o
Diverted after subjected to pressure and air tightening test at site to see that there will be no problem
For 1st. stage suction separator
(drain trap; 1, by-pass valve;2,strainer: 1, other piping valve: 1)
1set 5sets oRenewed by changing proof pressure according to increased discharge pressure
Snubber
1st. stage suction separator 1set 5sets o Renewed due to the change in cylinder
size
2nd. stage suction separator 1set 5sets o
Renewed by changing proof pressure according to increased discharge pressure
Receiver
Receiver 1set oRenewed by changing proof pressure according to increased discharge pressure
For Receiver (drain trap;1, by-pass valve;2,strainer: 1, other piping valve: 1)
1set o
LubricatorLubricator (Include bracket, sprocket, oil seal)
1set 5sets o Renewed due to aged deterioration
Frame lube unit
Pump, motor, piping valve, oil filter (1), oil filter (2), tank, level gauge
1set 5sets o Renewed due to aged deterioration
Radiator Radiator 1set 6sets o Renewed due to aged deterioration
Pipingvalve
Check valve 2sets 10sets o
Renewed by changing proof pressure according to increased discharge pressure
Main discharge valve8B 1pcs 5pcs oValve for receiver 8B 2pcs oValve for control valve6B 2pcs oControl valve 1set o Replaced with new one as a whole.
Pipingmaterial
Gas piping, cylinder and rod packing lubrication piping, frame lubrication piping, vent piping
5sets oExisting piping is diverted as possible, using spacers, short pipes, etc
Existing piping is diverted as possible, using spacers, short pipes, etc
Instrument
Pressure gauge, pressure switch, temperature gauge, temperature switch, flow sight
5sets oRenewed by changing proof pressure according to increased discharge pressure
Gaugestand
Gauge stand 1set 5sets o Only the replacement of measuring instruments is performed
SafetyvalveInstrument
For 2nd stage ditch. 1set 5sets oRenewed by changing proof pressure according to increased discharge
Pressure gauge, pressure switch, temperature gauge, temperature switch, flow sight
1set o
2-160-
Table 2.4-6 (2) Scope of Diverted Parts and Modified Parts (SITE GT PS)
2) Spare parts
For 1 For 5 SpareParts name unit units parts
1st stage suction 4sets 20sets 12sets
1 Cylinder valve assay 1st stage discharge2nd stage suction
4sets4sets
20sets20sets
12sets12sets
2nd stage discharge 4sets 20sets 12sets
o Valve plate 1 st stage 8pcs 40pcs 120pcs2nd stage 8pcs 4 Opes 120pcs
Valve spring 1st stage 1set 5sets 1 Ssets3 2nd stage 1set Ssets 1 Ssets
4 piofnn rinn 1 st stage 2pcs 10pcs 30pcs2nd stage 4pcs 2upcs 60pcs
C Rider ring 1 st stage 2pcs 10pcs 30pcs0 2nd stage 2pcs 10pcs 30pcs6 Rod packing 14sets 70sets 210sets7 Pressure breaker 2pcs 10pcs 30pcs8 Oil scraper ring 8sets 40sets 120sets9 Main bearing (1) 1set Ssets 1 Ssets10 Main bearing (2) 1set Ssets 1 Ssets11 Large end bearing 2sets 10sets 30sets12 Small end bearing 2pcs 10pcs 30pcs13 Cross bearing 4pcs 20pcs 60pcs
14 Gasket for parts replacement of compressor 1set 4sets Ssetsmam unit
15 Spare parts for radiator — 6sets 1 Ssets
16 Tube nest for inter cooler 1set Ssets 1set(With spare gasket)
17 Tube nest for after cooler 1set Ssets 1set(With spare gasket)
18 Air breather 1set Ssets 1set19 Crank shaft 1pcs Spcs 1pcs20 Coupling 1set Ssets 1set21 Connecting rod 2sets 10sets 2sets22 Cross head, Cross shoe *1 2sets 10sets 2sets23 Spare parts for Oil pump 1set Ssets Ssets24 Element for lubricator 1set 4sets 4sets25 Spare parts for control valve 1set 1set 1set
Note: The quantity may be changed in detail design.
*1 One upper cross head shoe and one lower crosshead shoe make a pair.
-2-161
3) Generator
It is recommend that a rotor pull-up check and other inspections to conduct an elaborate survey of the damage and insulation status of the various parts of the existing generators. However, it is clear that the generators have been considerably deteriorated, and they should be subjected to either of the following two cases:
Case 1: Replacing the generators proper
Case 2: Rewinding the rotor coils and the stator coils of the generators and replacing the retaining coils. (For other parts, the existing equipment will be diverted unless there is particular damage or other defect.)
Table 2.4-7 shows the details of the specifications of the generators in each case.
Table 2.4-7 Specifications of the generators
Item Case 1 Case 2Model Synchronized
generator, open draft type, three-phase
Ditto
Capacity (kVA) at an atmospheric temperature of 15°C (=59°F)
33,630 29,940
Installed location Outdoors DittoRated power factor (PF) 0.8 DittoRated output (kW) at an atmospheric temperature of 15°C (=59°F)
26,900 23,950
Frequency (Hz) 50 DittoRated engine speed (rpm) 3,000 DittoRated voltage (V) 11,500 DittoRated current (A) 1,688 1,503Number of phases 3 phases DittoShort-circuit ratio 0.49 or more DittoInsulation type/top temperature limit
Type F/B rise (IEC 34/IEC 34)
Type F/ F rise (JEC-114/JEC-114)
Neutral grounding system Neutral point transformer
Ditto
Turning direction Clockwise as viewedfrom turbine
Ditto
Exciter type Blushless with PMG Static typeApproximate dimensions of generator (m) (LxWxH)
6.8X3.8X52* 7.8X6.5X4.1 **
Approximate weight of generator (t)
75* 78**
* : Includes the filter unit (but not the reduction gear). **: Includes the filter unit and reduction gear.
-2-162-
The personnel of this power station surveyed wish to use their generators and other existing equipment that can continue to be used.
If, in response to the above requirements, they replace only the gas turbines and operate the generators as they are, a rise in output due to the replacement of the gas turbines will increase the armature current and the field current, resulting in the temperature rise higher than under the existing conditions. This means the acceleration of insulation deterioration. What is more, since the equipment is constantly run at high temperature, there is a higher risk of a major accident resulting from an over current or other event.
If it is necessary to check the deterioration status of the rotor coil and stator coil in the existing generators, an insulation diagnosis can be conducted to check the deterioration status. However, if the turbines continue to run for some decades after they are replaced with high-output machines, it will be desirable to rewind at least the rotor coils and stator coils shown in Case 2.
If stator coils are rewound, the generators will be restored almost to their initial performance and can be reused. However, since the temperature rise regulations are of the F type in the current specifications, it is difficult to achieve any value equal or superior to the current rated output of the generators and the gas turbines will run at a partial load. If the locals wish to make 100% of the gas turbine performance, they will need to replace the generators.
Fig. 2.4-24 and 2.4-25 are external views (typical) of the generators in each case. The characteristics of Case 1 and Case 2 are shown in Table 2.4-8.
When case 1 is adopted, the generator capacity can be set to a setting that matches the rise in output due to the replacement of the gas turbines. The exciter can be changed to a brushless, PMG system, thus obviating the need of an excitation brush and the need of period brush replacement and other maintenance.
However, the rise in the outside dimensions of the generators and the reduction gears makes it difficult to install the generator panel (GAC) immediately after the generator. It is necessary to rearrange the system and modify its foundation.
When case 2 is adopted, the generator capacity will remain the same as the current generator specifications, with no change in the outside dimensions and other specifications. It will not be necessary to modify the foundation or rearrange the system.
The period require for the modification will be almost the same in case 1 and 2 when considered on the basis that the generators would be purchased.
2-163
Table 2.4-8 Characteristics of Generator Modification
Case 1 Case 2Power generator output
26,900 kW (at an atmospheric temperature of 15°C)
23.950 kW (at an atmospheric temperature of 15°C)
Insulation type/top temperature limit
Type F/B rise (IEC 34/IEC 34)
Type F/F rise (JEC-114/JEC-114)
Exciter Blushless with PMG Static typeMaintenance-free Maintenance required
Arrangement and foundation
Modification required (The generator panel (GAC) must be rearranged to meet the rise in the outside dimensions of the generators and the rise in the outside dimensions of the reduction gears.)
Modification not required
Modificationperiod
Approx. 9 months1) Manufacture: 6 months2) Transportation: 2 months
(Marine and inland transportation)3) Installation: 0.5 months
Approx. 9 months1) Procurement of materials and
replacement parts: 4 months2) Transportation: 2 months
(Marine and inland transportation)
3) Rewinding: 3 months (including disassembly and reinstallation)
***: To be considered on the basis of generator purchase.
2-164
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2-165•166 —
Fig. 2.4-24 General Arrangement of Generator (Typical)
(In Case of Generator Replace - Case 1 )
2.56
Fig. 2.4-25 (1) General Arrangement of Generator
(In Case of Generator Rewinding - Case 2 (1/2))
-2-167'lGS-
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THE KAR6CHI ELECTRIC SUPPLY CORPORATION LIMITED
KORANGt TOWN GAS TURBINE POWER STATION
CONSULTANTS : FlCHTNEH. CONS ULTIMO ENGINEERS
.THIRD GENERATORj?r# .<•—«^j4^L jT-'-ff CONNECTION OUTLINE
(ARRANGEMENT )
Hitachi. Ltd. 100 —080-736 a
Fig. 2.4-26 (2) General Arrangement of Generator
(In Case of Generator Rewinding - Case 2 (2/2))
2-169-170
4) Electrical system
The study results of each case are shown below,
a) Case 1
The existing equipment will be used for the generator, generator circuit breaker, PT, SA current transformers and generator neutral grounding equipment installed in generator auxiliary compartment. However, since the excitation type of generator will be changed from a static excitation type to a brushless excitation type, the existing excitation transformer will be removed. That is, all existing electrical equipment of generator main circuit will be used as it is, except the excitation transformer. In response to the replacement of the generator, the existing excitation systems and generator control panel will be renewed.
isting transformer is specified as 3QMVA at 40 degree C. If it is proposed that the main transformer has been produced as the standard of ANSI/IEE C57. 92,1981, this transformer capacity is acceptable to the increase of generator output as shown in Fig. 2.4-26. Therefore, the existing main transformer can be diverted.
The one-line diagram of the KORANGI GT PS is shown in Fig. 2.4-27, while that of the SITE GT PS is shown in Fig. 2.4-28.
b) Case 2
Since no change has been made in the specifications of the generator or excitation systems, the existing equipment will be used for the generator, generator circuit breaker, PT, SA current transformer, generator neutral grounding equipment and excitation transformer installed in generator auxiliary compartment. That is, all existing electrical equipment of generator main circuit will be used. Since the existing generator will be used, the existing generator excitation systems and generator control panel will be used.
The one-line diagram of the KORANGI GT PS is shown in Fig. 2.4-29, while that of the SITE GT PS is shown in Fig. 2.4-30.
2-171
CA
PAC
ITY (M
VA)
39.58MVA
39.58MVA
37.08MVA
33.33MVA
33.63MVA
30MVA
GEN. CAPACITY
28.57MVA !
AMBIENT TEMPERATURE (°C)
Fig.2.4-26 Step-up Transformer Capability
TO 87TA
TO STEP-UP TRANSF,
AI BUS DUCT
3 WIRE 11.5kV 50Hz
BCTx3 C200 2000/5A
521113. 8kV | 2000A
500MVA
01 BCTxl 0. 6B4 2000/5A
BCTx2 0. 6B4 2000/5A
T
PTx2
12000/120V 0.3W.X.Y.Z , 1.2ZZ
PTx2 A
12000/120V 0.3W.X.Y.Z, 1.2ZZ
a r— ASURGE 1 i DLAx3CAPx3 <t» • 12kV
13.8kV
]
VT 1
0.25/i F
AVR
IGBT BRIDGE
^GENERATOR^— |RSR
-M-
BCTx3 C200 2000/5A
BCTx3 C200 2000/5A
BCTx3 20VA 2000/1 A, 10P10
NEUTRAL GND. TRANS.
12000/240V Sr 1 okVA
1NCR
1.080205A1MIN.
64F
(SYN.)
—
\.....
-e-
GENERATOR PROTECTION & METERING SYSTEM
GEN. METERING
A , V , W , Var Wh , PF , Hz
^ ^ ^ g|
GEN. PROTECTION (DIGITAL)
87G , 59 , 32 , 40 , 46 51V , 64G , VTFF , 86
132kV
r 4 4 6
STEP—UP( TRANSF.)
□
COMMONAUX.TRANSF.
MAINAUX.TRANSF.
□ Q □
KEY PLAN
©
NOTEENCLOSED WITH ARE REPLACED. OTHER EQUIPMENT ARE USED WITHOUT MODIFICATION.
EQUIPMENT LOCATION KEY © TURBINE CONTROL PANEL DEVICE
© GENERATOR CONTROL PANEL DEVICE
A GEN AUX COMPT DEVICE
m GENERATOR COMPT DEVICE
Fig. 2.4-27 One Line Diagram (KORANGI GT PS, Case 1)
J
-2-173-174-
TO STEP-UP TRANSF. TO 87T
NOTEENCLOSED WITH ARE REPLACED. OTHER EQUIPMENT ARE USED WITHOUT MODIFICATION.
EQUIPMENT LOCATION KEY
A PURCHASER’S EQUIPMENT
Q TURBINE CONTROL PANEL DEVICE
$ GENERATOR CONTROL PANEL DEVICE
A GEN AUX COMPT DEVICE
EB GENERATOR COMPT DEVICE
Eg REMOTE CONTROL PANEL DEVICE
A AUXILIARY PANEL
Fig. 2.4-28 One Line Diagram (KORANGI GT PS, Case 2)
— 2—175 * 176 —
TO 87T TO STEP-UP TRANSF.
||BUS DUCT1.5kV 50Hz3 WIRE
BCTx3 C200 2000/5A
12000/120V0.3W.X.Y.Z .1.2ZZ
COMMONAUX.TRANSF.
STEP-UPTRANSF.» 500MVA 3.45kV
MAINAUX.TRANSF.
NORMALAUX.TRANSF.
GENERATOR PROTECTION & METERING SYSTEM
GEN. METERINGBCTxl 0. 6B4 2000/5A
BCTx2 0. 6B4 2000/5A
KEY PLANA , V , W , Var
12000/120V0.3W.X.Y.Z, 1.2ZZ
GEN. PROTECTION (DIGITAL)
13. 8kV NOTEENCLOSED WITH ARE REPLACED. OTHER EQUIPMENT ARE USED WITHOUT MODIFICATION.IGBT BRIDGE
EQUIPMENT LOCATION KEYGENERATOR =
TURBINE CONTROL PANEL DEVICE
GENERATOR CONTROL PANEL DEVICE
GEN AUX COMPT DEVICE
GENERATOR COMPT DEVICE]BCTx3 C200 2000/5A
BCTx3 C200 2000/5A
BCTx3 20VA 2000/1 A, 10P10
NEUTRAL GND. TRANS. Fig. 2.4-29 One Line Diagram12000/240V 1OkVA A
1.080
2-177-178
TO STEP-UP TRANSF.
A
ATO132kV (BBC)
> SYNCHRO EOIP.
40)------A™
132kV
COMMONAUX.TRANSF.
STEP-UP, TRANSF. , 3. 45kV
MAINAUX.TRANSF.
NORMALAUX.TRANSF.
KEY PLAN
ENCLOSED WITH I IARF REPLACED. OTHER EQUIPMENT ARE USED WITHOUT MODIFICATION.
EQUIPMENT LOCATION KEY
A PURCHASER’S EQUIPMENT
0 TURBINE CONTROL PANEL DEVICE
0 GENERATOR CONTROL PANEL DEVICE
A GEN AUX COMPT DEVICE
EB GENERATOR COMPT DEVICE
REMOTE CONTROL PANEL DEVICE
0 AUXILIARY PANEL
NEUTRAL GND. TRANS.
12000/240VlOkVA
1.080
Fig. 2.4-30 One Line Diagram (SITE GT PS, Case 2)
-2-179-180
2.4.2 Instrumentation and control (l&C) plan
(1) Basic policy of instrumentation and control plan
Instrumentation and control system of the latest gas turbines will be planned according to the following policy:
a) The existing equipment will be reused if it is possible to use.
b) The existing gas turbine control unit will be replaced to the latest models.
c) Operation and control system including start-up and shutdown can be monitored from the remote control room. This system is no need the assignment of personnel in the local control room.
For b), the existing control system is cannot control the latest gas turbine.
eplaced th( latest model because this system
For c), the latest control system is dramatically advanced human-machine interface (HMI). This system can be so built that it needs no personnel to be assigned in the local control room and enables personnel to monitor the operation from a remote location.
Fig. 2.4-31 shows a configuration of the control system after the replacement. When the plant is started up, the precondition is that the gas compressors should be started up and that the gas pressure required for the gas turbines should be secured just as before. The basic requirement is to allow the personnel to do so with the HMI for the new controllers from the remote control room.
The control system after the replacement is planned as follows:
a) The start-up operation of required number of gas compressor is held at the local.
b) The start-up of the plant after the checkup and other operations are over at the site is conducted through the HMI installed in the remote control room. Normal shutdown is also operated through the system installed in the remote control room.
c) After gas turbine speed reaches a rated speed, a synchronous check will be operated through the HMI installed in the remote control room. The automatic synchronizer (AS) will cause the gas turbine generator to be incorporated automatically into the power system, resulting in an automatic rise to a predetermined load. After that, normal operation and monitoring during plant operation will be operated through the HMI installed in the remote control room and through the existing gas turbine remote control panel (only the monitoring function for the electrical equipment is reused).
d) The gas turbine emergency close switch is installed on the existing gas turbine remote control panel.
-2-181-
(LOCATED IN REMOTE CONTROL ROOM)
(LOCATED IN CONTROL COMPARTMENT)REMOTE
GT CONTROL LOCAL AREA NETWORK
[AVR PANEL]
(CPU UNIT)[GT CONTROL PANEL] (CPU UNIT)
LOCAL
[GT CONTROL PANEL][GT CONTROL PANEL] [THYRISTOR PANEL]
CS, COS
EXISTING
FIELD
FIELDSOLENOIDSERVOFIELDLT SW
SWITCHPICKUP VALVEVALVECURRENT
AUXILIARY
GEN PROTECTION RELAY GEN PROTECTION RELAY
GT REMOTE PANEL
(EXISTING)OPERATOR
LOCAL
INTERFACE
REMOTE
OPERATOR
INTERFACE
SERVO(TB)
Pl/O (TB)
THYRISTORPl/O (TB)
Fig. 2.4-31 (1) Control System Configuration after Renewal
Case 1 (Generator: Reolaced. GT: Reolaced to Latest Tvoe)
Abbrev at ion
CPU : Central Processing Unit TR : Transducer
Pl/O : Process Input/Output RTD : Resistance Temperature Detector
TB Terminal Block VT : Voltage Transformer
MCC : Motor Control Center CT : Current Transformer
LVDT : Linear Voltage Differential CS : Control Switch
Transformer COS : Change Over Switch
-2-182-183-
LT SW: Limit Switch
(LOCATED IN REMOTE CONTROL ROOM)
(LOCATED IN CONTROL COMPARTMENT)
REMOTEGT CONTROL LOCAL AREA NETWORK
[GT CONTROL PANEL][AVR PANEL][GT CONTROL PANEL]
CPU UN
EXISTING
LOCAL
[GT CONTROL PANEL][GT CONTROL PANEL] [THYRISTOR PANEL] EXISTING
CS, COS
EXISTING
FIELD
FIELDSPEED SOLENOIDSERVO FIELDLT SWSWITCHPICKUP VALVEVALVE CURRENT
AUXILIARY
PROTECTION RELAY PANEL
GT CONTROL PANEL
(EXISTING)OPERATOR
INTERFACE
REMOTE
OPERATOR
NTERFACE
uru
SERVO(TB)
GEN PROTECTION CIRCUIT
Pl/O (TB)
THYRISTORPl/O (TB)
Fig. 2.4-31 (2) Control System Configuration after Renewal
Case 2 (Generator: Rewinding, GT: Replaced to Latest Type)
Abbreviation
CPU : Central Processing Unit TR : Transducer
Pl/O Process Input/Output RTD : Resistance Temperature Detector
TB Terminal Block VT : Voltage Transformer
MCC Motor Control Center CT : Current Transformer
LVDT Linear Voltage Differential CS : Control Switch
Transformer COS : Change Over Switch
2-184-185-
LT SW: Limit Switch
(2) Control function
1) Gas turbine
The digital control system that constitute the most important portion of gas turbine control is supplied a CPU incorporating a high-performance microprocessor. To increase reliability, the portion in charge of control and protection for main control unit consists of triple functional system: start-up, speed, load & temperature control and protection.
The gas turbine control system has the following functions:
- Start-up and shutdown control
- Speedup ratio control
- Speed/load factor control
- Exhaust gas temperature control
- Inlet guide vane control
- Water injection control
- Gas turbine over-speed protection
- Exhaust gas overheat protection (combustion anomaly monitoring)
- Flame loss (misfire) protection
- Gas turbine excessive vibration protection
2) Generator
Generator excitation system has the following functions:
- Automatic voltage regulation (AVR)
- Automatic power factor regulation (APFR)
When generator is operated parallel with the system, it is operated as a constant power factor (APFR). When a generator is operated alone and separately from the system, it is operated as a constant voltage (AVR).
3) Automatic and sequential control
When a gas turbine control system is accepted start-up operation order, this system controls gas turbine and auxiliary equipment automatically and sequentially till a preset output by an operator. At the shutdown procedure, an operator controls gas turbine and auxiliary equipment automatically and sequentially as the same situation.
4) Monitoring and operation
An operator can control gas turbines as start-up/shutdown and normal operation at remote control room using display that indicates the important monitoring items of gas turbine. He can also operate and monitor gas turbines in accident.
-2-186-
(3) Configuration of the controllers
The following control systems are installed at remote control room, local control room and local electrical room:
1) Remote control room
Remote control room is installed in service building and the following system is installed in it:
0 HMI (display and printer) of the latest control system
(D Gas turbine remote control panel
The following existing portion of the remote control panel will be reused.
- Power meter, voltmeter and synchronous monitor of generator
- Operating and monitoring portion of electrical equipment, such as operation switch of generator circuit breakers, operation switch of voltage control, etc.
Gas turbine emergency shutdown switch is installed in remote control panel.
2) Local control room
The following system is installed in local control room next to the gas turbine compartment:
0 Gas turbine control panel (new)
® Gas turbine generator control and protection panel (new)
(3) Automatic voltage regulator (new)
3) Local electrical room
The following electrical equipment related to gas turbine is settled in this room:
0 Gas turbine auxiliary equipment control centre
(D DC distribution panel
(3) Battery storage panel
0 Battery charge panel
(D Uninterruptible power supply panel
(0 DC motor start-up panel
0 Other distribution panel (lighting, work, etc.)
Table 2.4-9 and 2.4-10 show the changing points of control system accompanying to the replacement of latest gas turbine in each power station.
2-187
Table 2.4-9 Proposal Plan of l&C Equipment after Replacement / KQRANG1 GT PS
Equipment No. Name
Proposal plan
RemarksExisting use without
modification
Existing use with
motificationReplace Not required Additional
GasCompressor
1 Pressure Control Valve Yes* *lf not aged.2 Pressure Transmitter Yes* Yes *lf not aged.3 Thermocouple Yes* *lf not aged.4 Pressure Switch Yes* Yes *lf not aged.5 Controller Yes* *lf not aged.
Gas Turbine Compartment
1 Pressure Transmitter Yes2 Pressure Switch Yes3 Thermocouple Yes4 Resistance Temperature Detector Yes5 Turbine Supervisory Instruments
(1) Vibration Yes(2) Speed sensor Yes(3) Valve Stroke Sensor (LVDT) Yes
Gas FlowSkid
1 Orifice Yes2 Diffrencial Pressure Transmitter Yes3 Pressure Transmitter Yes4 Resistance Temperature Detector Yes5 Calculator Yes
Generator 1 Thermocouple Yes/case 2 * Yes/case 1 *lf not aged.2 Resistance Temperature Detector Yes/case 2 * Yes/case 1 *lf not aged.3 Vibration Yes/case 2 * Yes/case 1 *lf not aged.
CentralControlRoom
1 Remote Control Panel Yes2 Electrical Panel Yes3 Operator Station (CRT Display) Yes4 Printer Yes
ControlEquipment
1 GT Control Panel Yes2 Generator Control Panel Yes/case 2 Yes/case 13 Automatic Voltage Regulator Yes4 Protection Controller(Relay) for
Electrical Equipment Yes/case 2 Yes/case 15 DCS Yes6 Environmental Monitors Yes7 Other Control Equipment YesL -
Table 2.4-10 Propasal Plan of l&C Equipment after Replacement / SITE GT PS
Equipment No. Name
Proposal plan
RemarksExisting use without
modification
Existing use with
motificationReplace Not required AdditionaI
GasCompressor
1 Pressure Control Valve Yes* *lf not aged.2 Pressure Transmitter Yes* Yes *lf not aged.3 Thermocouple Yes* *lf not aged.4 Pressure Switch Yes* Yes *lf not aged.5 Controller Yes* *lf not aged.
Gas Turbine Compartment
1 Pressure Transmitter Yes2 Pressure Switch Yes3 Thermocouple Yes4 Resistance Temperature Detector Yes5 Turbine Supervisory Instruments
(1) Vibration Yes(2) Speed sensor Yes(3) Valve Stroke Sensor (LVDT) Yes
Gas FlowSkid
1 Orifice Yes2 Diffrencial Pressure Transmitter Yes3 Pressure Transmitter Yes4 Resistance Temperature Detector Yes5 Calculator Yes
Generator 1 Thermocouple Yes/case 2 * Yes/case 1 *lf not aged.2 Resistance Temperature Detector Yes/case 2 * Yes/case 1 *lf not aged.3 Vibration Yes/case 2 * Yes/case 1 *lf not aged.
CentralControlRoom
1 Remote Control Panel Yes2 Electrical Panel Yes3 Operator Station (CRT Display) Yes4 Printer Yes
ControlEquipment
1 GT Control Panel Yes2 Generator Control Panel Yes/case 2 Yes/case 13 Automatic Voltage Regulator Yes4 Protection Controller(Relay) for
Electric Equipment Yes/case 2 Yes/case 15 DCS Yes6 Environmental Monitors Yes7 Other Control Equipment Yes
2.4.3 Site layout plan
Site layout plan of the equipment is presented for each power station, because its geographical features and conditions are different.
(1) KORANGI GT PS
1) Location, topography, and foundation of the site
The location and topography of this power station are as shown in Fig. 2.2-33 of clause 2.2.1. The existing foundation is basically used but may need modification or add-on.
2) Layout plan conditions
Reconfiguration of the main equipment on the premises of this power station is roughly divided into turbine equipment, cooling water system, and fuel supply equipment and is positioned as follows:
a) Turbine equipment
Similarly to the existing equipment, transmission direction is southward. The existing equipment is removed, and the latest gas turbine equipment is installed.
b) Cooling water system
The existing system (cooling tower system) is removed, and a new radiator cooling system is installed.
c) Fuel supply equipment
Modified equipment is installed similar to the existing fuel equipment. Main fuel is natural gas, and oil (HSDO) is used for emergency.
3) Consideration items in layout plan
Consideration items in layout plan are described below,
a) Turbine equipment
- Latest gas turbine is the same weight as existing one. Therefore, location of the latest gas turbine, which is the heaviest of all components, is planned as the similar ground condition to the existing equipment.
- Latest gas turbine arrangement type is l-type arrangement and outdoor arrangement similarly to the existing equipment.
- Electrical room building for the new equipment is used the existing building.
- The existing main transformer is reused. Domestic transformer is the same situation.
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b) Cooling water system
- For the cooling water system, existing cooling tower is removed, and radiators for each unit are arranged near the latest gas turbines.
c) Fuel supply equipment
- Fuel supply equipment supplies natural gas and oil as to existing equipment. Therefore, existing fuel supply equipment is reused.
d) Other equipment
- Existing air suction chamber is reused.
- For piping area and cable channel, the existing equipment is reused as much as possible.
- Existing generator equipment is replaced as much as possible.
4) Results of layout study
Results of the layout study considered the above layout conditions are described below.
a) Case 1
In case 1, existing generator is replaced the latest one. Outer dimension of new generator and auxiliary equipment is a little larger. Therefore, gas turbine and generator are located about 2 m to the main transformer. Gas turbine rotation speed is different from existing one. Therefore, outer dimension of the reduction gear room is a little changed. Existing cooling tower and cooling water pump are removed, and new radiator is installed near the latest gas turbine equipment.
Fig. 2.4-32 shows the layout based on the above consideration results.
b) Case 2
In case 2, existing generator is rewound and reused. Therefore, location of the generator is not changed. However, outer dimension of the reduction gear room is a little changed due to the change in the gas turbine. Existing cooling tower and cooling water pump are removed, and new radiator is installed near the latest gas turbine equipment.
Fig. 2.4-33 shows the layout based on the above consideration results.
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2-192-193
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Fig. 2.4-33 General Layout of KORANGI GT PS (Case 2)
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(2) SITE GT PS
1) Installed location, topography and foundation of the installation site
Location and topography of the site for this power station is as shown in Fig. 2.2-64 of clause 2.2.2. Existing foundation is basically used but may need modification or add-on.
2) Layout conditions
Reconfiguration of the main equipment on the premises of this power station is roughly divided into turbine equipment, cooling water system, and fuel supply equipment and is positioned as follows:
a) Turbine equipment
Similarly to the existing equipment, transmission direction is southward. Existing equipment is removed, and latest gas turbine equipment is installed.
b) Cooling water system
Existing cooling water system (radiator) is removed, and a new radiator is installed.
c) Fuel supply equipment
Fuel supply equipment supplies natural gas and oil as to existing equipment. Therefore, existing fuel supply equipment is reused.
3) Consideration items in layout plan
Consideration items in layout plan are described below.
a) Turbine equipment
- Latest gas turbine is the same weight as existing one. Therefore, location of the latest gas turbine, which is the heaviest of all components, is planned as the similar ground condition to the existing equipment.
- Latest gas turbine arrangement type is l-type arrangement and outdoor arrangement similarly to the existing equipment.
- Electrical room building for the new equipment is used the existing building.
- The existing main transformer is reused. Domestic transformer is the same situation.
b) Cooling water system
- For cooling water system, existing radiator is removed, and radiator for each unit is placed near the latest gas turbine.
c) Fuel supply equipment
- Fuel supply equipment supplies natural gas and oil as to existing equipment. Therefore, existing fuel supply equipment is reused.
d) Other equipment
- Existing air suction chamber is reused.
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- For piping area and cable channel, the existing equipment is reused as much as possible.
- Existing generator equipment is replaced as much as possible.
4) Results of layout study
Results of layout study based on the above layout conditions are described below,
a) Case 1
In case 1, existing generator is replaced the latest one. Outer dimension of new generator and auxiliary equipment is a little larger. Therefore, gas turbine and generator are located about 2 m to the main transformer. Gas turbine rotation speed is different from existing one. Therefore, outer dimension of the reduction gear room is a little changed. Existing radiator in the accessory compartment is removed, and new radiator is installed near the latest gas turbine equipment.
Fig. 2.4-34 shows a layout based on the above survey results.
b) Case 2
In case 2, existing generator is rewound and reused. Therefore, location of the generator is not changed. However, outer dimension of the reduction gear room is a little changed due to the change in the gas turbine. Existing radiator is removed and a new radiator is placed near the latest model gas turbine equipment.
Fig. 2.4-35 shows a layout based on the above survey results.
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SWtrCHCOR BUI Due (mstfxeo*)
I
Fig. 2.4-34 General Layout of SITE GT PS (Case 1)
VIEW A-A
2-198-199
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Fig. 2.4-35 General Layout of SITE GT PS (Case 2)
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VIEW A-A
2.5 The range of funds, equipment, service, etc. to be supplied by the respective parties for the implementation of this project
KESC understands well the necessity to replace the gas turbine power station surveyed in this research and is therefore looking for a way to make the project a reality.
The important issue in implementing the project is finance. KESC regards this matter as a COM project and hopes that special environmental yen credit will be made a reality.
It will be specified the matters related to the fund in “3. Funding plan” to be mentioned later, and described the scope of works to be provided by each party by the time of realization of the project in this paragraph.
(1) Basic principles about the supply extend of the respective parties
In determining the supply range of both parties, we were based on the followingbasic principles:
1) Pakistan side will bear all the expenses related to the rehabilitation of the facilities.
2) Dispatching of technical person from Japan has been limited to that of personnel necessary to the explanation of the CDM and person to render technological supports.
Those are the decisions. In the stage of project implementation, it is necessary to hold a discussion and to determine the details each other.
(2) Specific extent of the respective parties
It is listed below the particulars discussed with KESC regarding the scope of works each party.
1) Rehabilitation of the facilities
Generators will be replaced (case 1) and generators will be reused after rewinding of the rotor coils and stator coils (case 2). The rehabilitation cost is discussed in each Case.
2) Dispatching of technical person
The dispatching time and number of technical person from Japan is discussed.
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2.6 Prerequisites and problems for the implementation of this project
The prerequisites, problems, and issues for implementing the project have been confirmed as follows:
(1) Application for yen credit
1) At the time of application for yen credit, it will be premised that the Pakistani Government recognizes this matter as a COM project.
2) It is also important to have the Pakistani Government recognize the significance of this matter and advance the priority ranking of the yen credit matter.
(2) Realization of the project
1) Prerequisite
a) When applying for permit of the project, KESC must determine which of the following cases proposed in 2.4 it will select.
Case 1: The gas turbines and generators will be replaced.
Case 2: The gas turbines will be replaced, but the generators will be reused with their coils rewound.
b) The service scopes of both parties indicated in 2.5 will be negotiated again by KESC and the Japanese side at the time of implementation and will be confirmed together with the details.
2) Other problems and issues
A project schedule must be well negotiated and determined. Examples of the schedule items are listed below.
a) Which power station will be implemented first?
b) Which unit in the power station will be updated first?
c) What are the steps of transporting and installing the existing and latest models of equipment?
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2.7 Project implementation schedule
In the case at this time, we have deliberated the processes from the fund raising to the realization of the project in the event that the fund raising progressed from the new fiscal year as scheduled
The table 2.7-1 and 2.7-2 are indicated the schedule up to the realization of the project.
The case at this time is the processes in the event that the fund raising progressed as scheduled, and actual processes need to be discussed with KESC and Pakistani Government.
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Fig. 2.7-1 Project Implimentation Schedule (by Yen Credit)
MONTHS1 2 3 4 5 6 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40
Document preparation
Requirement from Pakistani Government Examination and Requirement
2 Supply fromJapanese Government
Document Accept and Examination
! Crdit proceedings and decision
Detail discussion
3 Project ExecutionEquipment manufacturing
Eouioment transnortation and construction
Fig. 2.7-2 Project Implimentation Schedule (by Domestic Loan)
MONTHS12 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40
1 Fund laisingby Pakistani Government
Document preparation
Examination and Requirement i ;
2 Loan fromDomestic finance
Crdit proceedings and decision
i; I
3 Project ExecutionDetail discussion
Equipment mam facturing
' Equipment transpo
1 :
rtation and construction
1 Test .
3. Materialization of the funding proposal
As described in 2.4, we proposed the following two cases as a means of implementing the project:
Case 1: The gas turbines and generators will be updated.
Case 2: The gas turbines will be updated, but the generators will be reused with their coils rewound.
The above two cases are specified below in terms of required funds, methods of fundraising and other matters.
3.1 Funding proposal for the project implementation
(1) Required amount of funds
The fund requirement for the project was unable to be specified because our present survey did not cover the detailed design. However, as guidelines for calculating the effect of the project, we set the conditions for each of the above cases.
(Case 1) (1,000 dollars) (Case 2) (1,000 dolia
Gas turbines (9 units): 67,500 Gas turbines (9 units): 67,500
Generators (9 units): 9,000 Generators (9 units, rewound)
4,500
Peripherals, etc. 7,500 Peripherals, etc. 6,000
Total: 84,000 Total: 78,000
"Other" expenses include expenses for transportation, insurance, customs clearance, tasks (removal and installation) and instructor dispatch. But their details could not be monitored. However, the personnel expenses are as low as 100-600 rupees (1.5-10 dollars) per day. Engaging 100 workers for 3 months (for 20 working days per month) will cost only about 10,000-60,000 dollars.
(2) Method of fund raising
As for the method of fund-raising, KESC has high hopes for fund-raising by yen loans.
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3.2 Fund raising prospects
KESC is a government controlled corporation and is in a position where it can obtain governmental funds. What is more, KESC recently obtained IMF's guidance and obtained financial assistance from the ADB in the form of structural adjustment loans. However, funds of the government and ADB are allocated to improving the financial condition of KESC, that is, repaying the debts and securing assets. In reality, funds for investment in plant and equipment are hard to come by. As the KESC expects much in the fund raising by yen credit, particularly the environment special yen credit, we requested them to discuss with the Pakistani Government about the prospects of the fund raising. In the case of yen credit is applied, a 15% of the total construction fund is to be borne by the KESC itself in accordance with the rule of the system. KESC has not made any statement about the raising of the fund to be borne by itself, but, similarly to the purchase of fuel oil and other electric power from other sources, the funds will presumably be secured with the Pakistani government guaranteeing the debts. We have requested to have discussions by the local Japanese corporations (trade firms and others) with regard to the other plans for fund raising.
3.3 In the implementation of the project
As stated in the paragraph 2.4 of this Chapter and Chapter 3, the performances of the new model of gas turbines can be demonstrated in Case 1, and the effects of the energy saving and reduction of greenhouse gas in the Case 1 is greater than those in the Case 2. For this reason, we recommend the Case 1 in the implementation of the project. However, the Case 1 requires a fund of about 6 million dollar more than the Case 2 and therefore requires harder fund raising. In the implementation of the project, we will select the Case to be adopted considering its suitability to the circumstances and requirement of the country concerned at the time of implementation.
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4. Issues related to CDM conditions
This survey was conducted as a CDM project. At the site, we surveyed the ideas of the Pakistani Government and KESC about the CDM and summarized the matters related to the CDM conditions as follows:
4.1 Coordination items with Pakistan side to realize the CDM project
Pakistan has no clear-cut standards for cutting emissions of carbon dioxide. However, the Pakistani Government does recognize that replacing the current aged equipment will not only reduce carbon dioxide but save energy, or reduce fuel expenses, as well.
KESC has also stated its intention to approach the government about this project as a project worthy of yen loans. However, if this project is made subject to yen loans, KESC wishes to apply for the project as a comprehensive rehabilitation project including steam thermal power stated in 1.2 of Chapter 1.
In order to realize the CDM, it is important to have the Pakistani Government request the Japanese Government for yen credit making this matter a CDM matter, and the KESC has clearly stated that it would work upon the Pakistani Government about this project as an issue of requesting for yen credit. To make this matter a CDM project, it is the primary method to have the Pakistani Government to adopt it as a yen credit matter, but before that, it is more important to pave the way to an environment in which the Japanese Government will easily render its supports for the CDM project upon the Pakistani Government’s request for yen credit. In other words, the Japanese Government should:
1) Obtain the understanding of the Pakistani Government with regard to the implementation of the CDM, and
2) Set up the clear and definite standards of the CDM.
Although it is difficult to realize these in the present situations in Pakistan, we will continue to work upon the Pakistani Government through KESC.
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4.2 Possibility of forming a consent to make this project as CDM
In view of its current status, KESC is very likely to agree to this project as part of the CDM. However, if it agrees to it as part of the CDM, KESC wishes to make it a comprehensive rehabilitation project involving steam thermal power plants as described above. Here are the reasons:
1) The steam thermal power plants have problems similar to those of the gas turbine power stations.
2) Involving steam thermal power plants is expected to save energy, reduce fuel consumption, and cut emissions of carbon dioxide in larger scale.
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Chapter 3 Effect of the Project
It is described in this chapter that the results of our study of the energy saving effect and greenhouse gas reduction effect of the following two cases described in 2.4 of Chapter 2.
Case 1: Gas turbines and generators are replaced.
Case 2: Gas turbines are replaced, and generators are reused after rewinding their stator coil.
As for the energy saving effect and greenhouse gas reduction effect, it is established that technical backgrounds for the energy saving effect, set a baseline as the basis for calculations, and performed a quantitative study according to the baseline, and state the results. It is also described the monitoring method for those effects.
It is stated that the observation result of the effect of this project on productivity in terms of productivity and energy consumption unit.
1. Energy saving effect
1.1 Technical background for the energy saving effect
Power generating facilities operated more than twenty years have much degraded in performance, and they cannot be completely recovered by normal maintenance inspections. KORANGI and SITE GT PS covered in our present survey (hereinafter referred to as "the two power stations") were surprisingly well maintained in general. However, as described in clause2.2 of Chapter 2, they have not been held a major overhaul, so that they have seriously degraded.
On the other hand, the technical advances for the past two decades have made a dramatic improvement in the performance of the gas turbines. Therefore, there is a better way than to keep running the old-model gas turbines as they are with some preventive inspection performed. The better way, which will increase output and thermal efficiency greatly, is to replace those gas turbines. The latest model of gas turbine is capable of high-speed revolution with high-temperature gas with the following characteristics:
(1) The material of the turbines has greater durability against high temperature than that of the existing turbines
(2) The gaseous resistance of the turbines is lesser than that of the existing turbines
When the gas gains high temperature, its workload increases because its volume inflates, and in addition, the power output of the turbine is increased by the high-speed revolution. Also, when the gaseous resistance becomes lesser, the loss of energy due to friction decreases and the energy conversion efficiency rises.
Therefore, the power output will be improved by 28 to 42%, and the heat efficiency, by 46 to 55 % in comparison with those of the existing turbines. Even in comparison with the design
values (the guaranteed values at the time of delivery) of the existing turbines, both the power output and heat efficiency will be higher by about 14%
A quantitative study of the energy-saving effect when the gas turbines will be replaced at the two power stations will be given in detail in clause 1.3.
1.2 Baseline to calculate the energy saving effect
Our present comparative study covered the following cases:
Case 1: Gas turbines and generators are replaced.
Case 2: Gas turbines are replaced, and generators are reused after rewinding their stator coil.
The effects are compared under identical conditions in each case.
(1) Prerequisites
In an assessment of the energy saving effect when implementing the project and the effect of reducing greenhouse gas (carbon dioxide), we set the following prerequisites:
1) Production of electric power before and after the project
Updating the gas turbines will result in higher performance and larger output. If the running time is set to the same level before and after the project, the total generated energy for the year will differ, resulting in failure to compare the systems under identical conditions. Generated power is thus set to the same level before and after the project. It will be assumed that, in Cases 1 and 2 after the project, energy saving and the reduction of greenhouse gases will result from cuts in fuel consumption through higher performance. More specifically, with the power consumption generated for a year from July, 1999 to June, 2000, we will calculate the effects of producing the same power consumption in Cases 1 and 2. This assumption will be applied to the two power stations.
2) Performance of the new-model gas turbines
The output and efficiency of the gas turbines will vary with atmospheric temperature. Output and efficiency therefore vary with the season and running time zone and varies similarly with fuel consumption. Before the project, we will use the totals obtained from annual operation data. After the project, however, it is impossible in actual practice to calculate the corresponding output and fuel consumption on the basis of hourly atmospheric temperatures. In assessment, therefore, the conditions will be the same at an atmospheric temperature of 30°C. This temperature almost corresponds to the average annual atmospheric temperature from evening to night under which the gas turbines are actually run. It also corresponds to the annual average operational conditions of the installed gas turbines.
The output and thermal efficiency of the new-model gas turbines at an atmospheric temperature of 30°C are 24,320 kW, 31.68% (Case 1) and 21,310 kW, 30.02% (Case 2) respectively on the basis of Figs. 2.4.1 and 2.4.2 indicated in 2.4 of Chapter 2.
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3) Performance of the gas turbines
The performance of the installed gas turbines varies with their respective operational track records, maintenance status, and individual differences. However, we will not compare the individual gas turbines. We will instead compare the power stations covered in terms of total power output.
4) Equivalent calorific value of crude oil
The equivalent calorific value of crude oil is set to 41,868kJ/kg (which is a conversion of 10,000kcal/kg) according to Article 3 of the "Law Enforcement Regulations Concerning the Rationalization in the Use of Energy" (a digested edition).
5) Calculating the reduction effect of carbon dioxide
The reduction effect of carbon dioxide will be calculated with the formula indicated in the "Guideline for the Calculation of Greenhouse Gas Emissions" listed in the References.
(2) Baseline
In the deliberation at this time, we used the results of the previous fiscal year for the baseline, but in case we did not carried out any particular undertaking in the previous year, we used the same result as that in the previous year, assuming that the same amount of fuels (natural gas and HSDO) had been supplied and the same watts-hour of power as the previous year had been generated using the fuels.
The amounts of the fuels and watts-hour of power generated at each power station in the previous year were as follows:
1) KORANGI GT Power Station
a) Fuel consumption
■ Natural gas: 4,831,000 MCF ■ HSDO: 69.6 m3
b) Power generation (total of four generators)
275,373 MW
2) SITE GT Power Station
a) Fuel consumption
■ Natural gas: 3,150,000 MCF ■ HSDO: 510.0 m3
b) Power generation (total of four generators)
191,184 MW
In the deliberation at this time, it is calculated on the basis of 10 years and 20 years assuming that the current conditions will last for such duration, but exactly speaking, such factors as further deterioration of the equipment and changes in the operational patterns can be considered. However, the latest gas turbines will also deteriorate to the same extent, and considering the conditions of fuel supplies in Pakistan, we deemed that we could not expect drastic changes in the operational patterns even if the existing gas turbines have been replaced by the latest models. For these reasons, we have set up the above values as a baseline.
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1.3. Specific quantity, observed period, and accumulated quantity of the energy-saving effect
<Case 1>
(1) Before the project
As operation data before the project, we used the data for the period from July, 1999 to June, 2000 obtained from the two power stations. Table 1.3-1 and 1.3-2 show the generated power and fuel consumption rates we obtained.
(2) After the project
For both power stations, we calculated the fuel consumption rates required to generate the same power rates with the new-model gas turbine as before the project. Table 1.3-1 and 1.3-2 show the equivalence of crude oil of fuel consumption.
Table 1.3-3 and 1.3-4 compare the energy-saving effects achieved before and after the project, as estimated on the basis of Table 1.3-1 and 1.3-2. After the project, increasing thermal efficiency is projected to save about 41,000 tons (35.4%) in annual fuel consumption in the KORANGI GT PS and about 24,000 tons (31.6%) in the SITE GT PS, in terms of crude oil. Assuming that the observed period of the effect is 15 years, the KORANGI GT PS will in the meantime save about 610,000 tons, and the SITE GT PS about 360,000 tons.
<Case 2>
(1) Before the project
The operational data in Case 2 before the project is identical with that in Case 1. The data about the two power stations is presented again in Tables 1.3.5 and 1.3.6 respectively.
(2) After the project
Similarly to Case 1, the fuel consumption rates required to produce the same amount of power as before the project with the new-model gas turbines were calculated for the two power stations. The fuel consumption rates in terms of crude oil are shown in Tables 1.3.5 and 1.3.6
Tables 1.3.7 and 1.3.8 are comparative tables that summarize the effects of energy-saving before and after the project on the basis of Tables 1.3.5 and 1.3.6. The fuel consumption rate for the year in terms of crude oil is projected to be saved by about 37,000 tons (31.8%) for the KORANGI GT PS and by about 21,000 tons (27.8%) for the SITE GT PS. Assuming that the observed period of the effect is 15 years, the savings in the meantime in terms of crude oil will be about 550,000 tons for the KORANGI GT PS, and about 320,000 tons for the SITE GT PS.
As described above, Case 2 will produce a lower effect of energy saving than Case 1. The reason in Case 2 will require the gas turbines to run at partial load, resulting in lower thermal efficiency. If the total power output is set to the same, Case 2 will consume more fuel than Case 1.
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1.4. A specific method of monitoring the effect of energy-saving
The effect of energy-saving will probably be monitored by the proposer (the Japanese side) or the implementer (the KESC side) of the project. The securest and most realistic implementer of the project would be the KESC, which owns the power stations.
Monitoring will be performed by measuring the generated power and fuel consumption rates before and after the project. Provided that the precondition is that the fuel flow meters that currently do not function should be repaired and periodically calibrated. The generated power can be measured with the watt-hour meter installed on the control board, and this meter needs periodic calibration as well.
It is able to verify the energy saving effects by having the KESC maintain the operational records, calculate the fuel consumption from such records on the Japan side and compare it with the fuel consumption made prior to the implementation of the project.
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Table 1.3-1 Energy Saving and CO2 Reduction of Replacing Existing Gas Turbines by Latest Gas Turbinesfor KORANGI GT PS (Case 1)
Item Units
Before Execution of ProjectAfter
Execution of Project Advantages
Existing Gas Turbine Latest Gas Turbine (4units)Unit No.1 Unit No.2 Unit No.3 Unit No.4 Total
Unit Generated Gas kWh 51,336,100 59,311,400 83,622,800 80,964,300 275,234,600 275,372,700
Oil kWh 51,700 69,900 16,500 - 138,100 -
Total kWh 51,387,800 59,381,300 83,639,300 80,964,300 275,372,700 275,372,700
Fuel Consumption Gas MCF/y 909,989 1,020,349 1,471,904 1,428,727 4,830,969 3,122,000 1,708,969
Oil Lit./y 25,664 35,956 7,941 - 69,561 - 69,561
Heat Consumptior Gas GJ/y 912,088 1,022,703 1,475,300 1,432,023 4,842,114 3,129,202 1,712,912
Oil GJ/y 933 131 29 - 1,093 - 1,093
Total GJ/y 913,021 1,022,834 1,475,329 1,432,023 4,843,207 3,129,202 1,714,004
Gross Heat Rate kJ/kWh 17,767 17,225 17,639 17,687 17,588 11,364
BTU/kWh 16,840 16,345 16,722 16,764 16,675 10,770
Gross Plant Efficiency % 20.26 20.88 20.41 20.35 20.46 31.68
Equivalent Calorific Value of Crude Oil
kJ/kg 41,868 41,868 41,868 41,868 41,868 41,868
Equivalent Consumption of Crude Oil
t/y 21,807 24,430 35,238 34,203 115,678 74,740 40,938
Equivalent Amount of Crude Oil
toe/y 21,807 24,430 35,238 34,203 115,678 74,740 40,938
Annual C02 Emission t-C02/y 67,476 75,591 109,033 105,832 357,932 231,261 126,672
Note; (1) The data of Item number 1 through 4 for existing gas turbine are supplied by the Korangi GTPS. (Data of July 1999-June 2000)(2) Total generated power (MWh) of latest gas turbines is assumed to be the same as that of existing gas turbines No.1-No.4.(3) Following heating values for fuel gas and oil (HSDO) are applied. (Standard value of KESC)
Natural gas ; 950 BTU/MCF Oil (HSDO) : 34,460 BTU/Lit.(4) Annual 002 Emission (t-C02/y)=Equivalent amount of crude oil (toe/y)/1000 X 42.62 X 20 X 0.99 X (44/12)
(Source: ' Greenhouse gas emission calculation guideline" issued by the Japanese Government)
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Table 1.3-2 Energy Saving and CO2 Reduction of Replacing Existing Gas Turbines by Latest Gas Turbinesfor SITE GT PS (Case 1)
Item Units
Before Execution of ProjectAfter
Execution of Project Advantages
Existing Gas Turbine Latest Gas Turbine (4units)Unit No.1 Unit No.2 Unit No.3 Unit No.4 Unit No.5 Total
Unit Generated Gas kWh 33,904,300 71,952,700 29,094,200 7,754,500 47,280,800 189,986,500 191,183,500
Oil kWh 772,400 221,800 163,600 39,200 - 1,197,000 -
Total kWh 34,676,700 72,174,500 29,257,800 7,793,700 47,280,800 191,183,500 191,183,500
Fuel Consumption Gas MCF/y 559,782 1,200,763 484,669 128,828 775,992 3,150,034 2,167,500 982,534
Oil Lit./y 330,836 92,003 69,485 17,719 - 510,043 - 510,043
Heat Consumptior Gas GJ/y 561,073 1,203,533 485,787 129,125 777,782 3,157,301 2,172,500 984,801
Oil G J/y 12,028 3,345 2,526 644 - 18,544 - 18,544
Total GJ/y 573,102 1,206,878 488,313 129,769 777,782 3,175,845 2,172,500 1,003,345
Gross Heat Rate kJ/kWh 16,527 16,722 16,690 16,651 16,450 16,612 11,363
BTU/kWh 15,665 15,849 15,819 15,782 15,592 15,745 10,770
Gross Plant Efficiency % 21.78 21.53 21.57 21.62 21.88 21.67 31.68
Equivalent Calorific Value of Crude Oil
kJ/kg 41,868 41,868 41,868 41,868 41,868 41,868 41,868
Equivalent Consumption of Crude Oil t/y 13,688 28,826 11,663 3,099 18,577 75,854 51,889 23,964
Equivalent Amount of Crude Oil
toe/y 13,688 28,826 11,663 3,099 18,577 75,854 51,889 23,964
Annual CO2 Emission t-C02/y 42,355 89,193 36,088 9,590 57,481 234,708 160,556 74,151
Note; (1) The data of Item number 1 through 5 for existing gas turbine are supplied by the SITE GTPS. (Data of July 1999-June 2000)(2) Total generated power (MWh) of latest gas turbines is assumed to be the same as that of existing gas turbines No.1-No.5.(3) Following heating values for fuel gas and oil (HSDO) are applied. (Standard value of KESC)
Natural gas : 950 BTU/MCF Oil (HSDO) ; 34,460 BTU/Lit.(4) Annual C02 Emission (t~C02/y)=Equivalent amount of crude oil (toe/y)/1000 x 42.62 x 20 x 0.99 x (44/12)
(Source: "Greenhouse gas emission calculation guideline" issued by the Japanese Government)
Table 1.3-3 Summary of Energy Saving and CO 2 Reduction Effectfor KORANGI GT PS (Case 1)
Item UnitsBefore
Execution of Project
After Execution of Project
ReductionEffect
Remarks
Equivalent Consumption of Crude Oil
t/y 115,678 74,74040,938(35.4%)
Annual Equivalent Amount of Crude Oil
toe/y 115,678 74,74040,938(35.4%)
C02 Emission t-C02/y 357,932 231,261126,672(35.4%)
Equivalent Consumption of Crude Oil
t 1,735,170 1,121,096614,074(35.4%)
15 Years *1)
Equivalent Amount of Crude Oil
toe 1,735,170 1,121,096614,074(35.4%)
CO2 Emission t~C02 5,368,984 3,468,9081,900,076
(35.4%)
Note *1) Annual generated power is assumed to be the same as that of first year during 15 years.
Table 1.3-4 Summary of Energy Saving and CO 2 Reduction Effectfor SITE GT PS (Case 1)
Item UnitsBefore
Execution of Project
After Execution of Project
ReductionEffect
Remarks
Annual
Equivalent Consumption of Crude Oil
t/y 75,854 51,88923,964(31.6%)
Equivalent Amount of Crude Oil
toe/y 75,854 51,88923,964(31.6%)
CO2 Emission t-C02/y 234,708 160,55674,151(31.6%)
15 Years *1)
Equivalent Consumption of Crude Oil
t 1,137,806 778,339359,467(31.6%)
Equivalent Amount of Crude Oil
toe 1,137,806 778,339359,467(31.6%)
CO2 Emission t~C02 3,520,614 2,408,3471,112,267
(31.6%)
Note *1) Annual generated power is assumed to be the same as that of first year during 15 years.
3-8
Table 1.3-5 Energy Saving and CO2 Reduction of Replacing Existing Gas Turbines by Latest Gas Turbinesfor KORANGI GT PS (Case 2)
Item Units
Before Execution of ProjectAfter
Execution of Project Advantages
Existing Gas Turbine Latest Gas Turbine (4units)Unit No.1 Unit No.2 Unit No.3 Unit No.4 Total
Unit Generated Gas kWh 51,336,100 59,311,400 83,622,800 80,964,300 275,234,600 275,372,700
Oil kWh 51,700 69,900 16,500 - 138,100 -
Total kWh 51,387,800 59,381,300 83,639,300 80,964,300 275,372,700 275,372,700
Fuel Consumption Gas MCF/y 909,989 1,020,349 1,471,904 1,428,727 4,830,969 3,295,000 1,535,969
Oil Lit./y 25,664 35,956 7,941 - 69,561 - 69,561
Heat Consumptior Gas GJ/y 912,088 1,022,703 1,475,300 1,432,023 4,842,114 3,302,602 1,539,512
Oil G J/y 933 131 29 - 1,093 - 1,093
Total GJ/y 913,021 1,022,834 1,475,329 1,432,023 4,843,207 3,302,602 1,540,605
Gross Heat Rate kJ/kWh 17,767 17,225 17,639 17,687 17,588 11,993
BTU/kWh 16,840 16,345 16,722 16,764 16,675 11,367
Gross Plant Efficiency % 20.26 20.88 20.41 20.35 20.46 30.02
Equivalent Calorific Value of Crude Oil
kJ/kg 41,868 41,868 41,868 41,868 41,868 41,868
Equivalent Consumption of Crude Oil
t/y 21,807 24,430 35,238 34,203 115,678 78,881 36,797
Equivalent Amount of Crude Oil
toe/y 21,807 24,430 35,238 34,203 115,678 78,881 36,797
Annual C02 Emission t-COz/y 67,476 75,591 109,033 105,832 357,932 244,075 113,857
Note; (1) The data of Item number 1 through 4 for existing gas turbine are supplied by the Korangi GTPS. (Data of July 1999-June 2000)(2) Total generated power (MWh) of latest gas turbines is assumed to be the same as that of existing gas turbines No.1-No.4.(3) Following heating values for fuel gas and oil (HSDO) are applied. (Standard value of KESC)
Natural gas : 950 BTU/MCF Oil (HSDO) : 34,460 BTU/Lit.(4) Annual 002 Emission (t-002/y)=Equivalent amount of crude oil (toe/y)/1000 x 42.62 x 20 x 0.99 x (44/12)
(Source: "Greenhouse gas emission calculation guideline" issued by the Japanese Government)
Table 1.3-6 Energy Saving and CO2 Reduction of Replacing Existing Gas Turbines by Latest Gas Turbinesfor SITE GT PS (Case 1)
Item Units
Before Execution of ProjectAfter
Execution of Project Advantages
Existing Gas Turbine Latest Gas Turbine (4units)Unit No.1 Unit No.2 Unit No.3 Unit No.4 Unit No.5 Total
Unit Generated Gas kWh 33,904,300 71,952,700 29,094,200 7,754,500 47,280,800 189,986,500 191,183,500
Oil kWh 772,400 221,800 163,600 39,200 - 1,197,000 -
Total kWh 34,676,700 72,174,500 29,257,800 7,793,700 47,280,800 191,183,500 191,183,500
Fuel Consumption Gas MCF/y 559,782 1,200,763 484,669 128,828 775,992 3,150,034 2,287,600 862,434
Oil Lit./y 330,836 92,003 69,485 17,719 - 510,043 - 510,043
Heat Consumptior Gas GJ/y 561,073 1,203,533 485,787 129,125 777,782 3,157,301 2,292,877 864,424
Oil GJ/y 12,028 3,345 2,526 644 - 18,544 — 18,544
Total GJ/y 573,102 1,206,878 488,313 129,769 777,782 3,175,845 2,292,877 882,967
Gross Heat Rate kJ/kWh 16,527 16,722 16,690 16,651 16,450 16,612 11,993
BTU/kWh 15,665 15,849 15,819 15,782 15,592 15,745 11,367
Gross Plant Efficiency % 21.78 21.53 21.57 21.62 21.88 21.67 30.02
Equivalent Calorific Value of Crude Oil
kJ/kg 41,868 41,868 41,868 41,868 41,868 41,868 41,868
Equivalent Consumption of Crude Oil
t/y 13,688 28,826 11,663 3,099 18,577 75,854 54,764 21,089
Equivalent Amount of Crude Oil
toe/y 13,688 28,826 11,663 3,099 18,577 75,854 54,764 21,089
Annual CO2 Emission t-C02/y 42,355 89,193 36,088 9,590 57,481 234,708 169,453 65,255
Note; (1) The data of Item number 1 through 5 for existing gas turbine are supplied by the SITE GTPS. (Data of July 1999-June 2000)
(2) Total generated power (MWh) of latest gas turbines is assumed to be the same as that of existing gas turbines No.1-No.5.(3) Following heating values for fuel gas and oil (HSDO) are applied. (Standard value of KESC)
Natural gas : 950 BTU/MCF Oil (HSDO) : 34,460 BTU/Lit.(4) Annual 002 Emission (t-C02/y)=Equivalent amount of crude oil (toe/y)/1000 x 42.62 x 20 x 0.99 x (44/12)
(Source: "Greenhouse gas emission calculation guideline" issued by the Japanese Government)
Table 1.3-7 Summary of Energy Saving and CO 2 Reduction Effect for KORANGI GT PS (Case 2)
Item UnitsBefore
Execution of Project
After Execution of Project
ReductionEffect
Remarks
Annual
Equivalent Consumption of Crude Oil
t/y 115,678 78,88136,797(31.8%)
Equivalent Amount of Crude Oil
toe/y 115,678 78,88136,797(31.8%)
CO2 Emission t-C02/y 357,932 244,075113,857(31.8%)
15 Years *1)
Equivalent Consumption of Crude Oil
t 1,735,170 1,183,219551,951(31.8%)
Equivalent Amount of Crude Oil
toe 1,735,170 1,183,219551,951(31.8%)
CO2 Emission t"C02 5,368,984 3,661,1311,707,853
(31.8%)
Note *1) Annual generated power is assumed to be the same as that of first year during 15 years.
Table 1.3-8 Summary of Energy Saving and CO 2 Reduction Effectfor SITE GT PS (Case 2)
Item UnitsBefore
Execution of Project
After Execution of Project
ReductionEffect
Remarks
Equivalent Consumption of Crude Oil
t/y 75,854 54,76421,089(27.8%)
AnnualEquivalent Amount
of Crude Oiltoe/y 75,854 54,764
21,089(27.8%)
CO2 Emission t-C02/y 234,708 169,45365,255(27.8%)
Equivalent Consumption of Crude Oil
t 1,137,806 821,467 316,340(27.8%)
15 Years *1)
Equivalent Amount of Crude Oil
toe 1,137,806 821,467316,340(27.8%)
CO2 Emission t-C02 3,520,614 2,541,792978,822(27.8%)
Note *1) Annual generated power is assumed to be the same as that of first year during 15 years.
3-11
2. Greenhouse gas reduction effect
2.1 Technical reasons for the greenhouse gas reduction effect
Gas turbines of the two power stations are operated more than 20 years, and their performance has declined so much that it cannot be recovered by maintenance as described before. What is more, the models are more than two decades old and have thermal efficiency 5-6% (in absolute value) than the latest-model gas turbines. This means that the fuel consumption rate required to produce an identical amount of electric power is about 30% higher. Since greenhouse gas is produced by the combustion of a fuel, cutting the fuel consumption will lead directly to cuts in greenhouse gases.
A quantitative study of the greenhouse gas reduction effect will be described in detail in clause 2.3.
2.2 The baseline as the basis for calculating the greenhouse gas reduction effect
The production of greenhouse gases accompanies the combustion of a fuel and is indivisible from the energy-saving effect. The prerequisites and the baseline described in clause 1.2 will therefore apply.
2.3 Specific quantity, observed period, and accumulated quantity of the greenhouse gas reduction effect
The annual emissions of carbon dioxide will be calculated by the formula set forth in the "Guideline for the Calculation of Greenhouse Gas Emissions" listed in the References. The below formula is applied to Cases 1 and 2.
Oil equivalent (toe/y) 44C02 equivalent (t-C02/y)=------------------------------x 42.62 x 20 x 0.99 x -----------
1,000 12<Case 1>
(1) Before the project
As operational data before the project, the data in Tables 1.3-1 and 1.3-2 used in considering the energy-saving effect will be used. The tables indicate the C02 emissions calculated with the formula indicated above.
(2) After the project
In calculating the carbon dioxide emissions, we based ourselves on the fuel consumption required to produce the same power rate as before the project with the new-model gas turbines. Table 1.3-1 and 1.3-2 show the calculation results. The C02 reduction effect before and after the project is shown in Tables 1.3-3 and 1.3-4 presented above.
3-12
After the project, the production of carbon dioxide for the year will be saved by about 127,000 tons (35.4%) for the KORANGI GT PS, and by about 74,000 tons (31.6%) for the SITE GT PS. Assuming that the observed period of the effect is 15 years, the C02 reduction effect in the meantime will be about 1,900,000 tons for the KORANGI GT PS, and about 1,100,000 tons for the SITE GT PS.
<Case 2>
(1) Before the project
As operational data before the project, Table 1.3-5 and 1.3-6 used in considering the energy-saving effect are used. The tables present the emissions of carbon dioxide calculated with the formula presented above.
(2) After the project
In calculating the emissions of carbon dioxide, we based ourselves on the fuel consumption required to produce the same power rate as before the project with the new-model gas turbines. Table 1.3-5 and 1.3-6 show the calculation results. The C02 reduction effects before and after the project are presented in Table 1.3-7 and 1.3-8 presented above.
After the project, the production of carbon dioxide for the year can be saved by about 114,000 tons (31.8%) for the KORANGI GT PS, and by about 65,000 tons (27.8%) for the SITE GT PS. Assuming that the observed period of the effect is 15 years, the C02 reduction effect in the meantime will be about 1,710,000 tons for the KORANGI GT PS, and about 980,000 tons for the SITE GT PS.
As described above, Case 2 will have a lower C02 reduction effect than Case 1.Why? Because Case 2 requires the gas turbines to run at partial load, resulting in lower thermal efficiency. As a result, if the total power output is set to the same, the fuel consumption in Case 2 will be more than in Case 1.
2.4 A specific method of monitoring the greenhouse gas reduction effect
The greenhouse gas (C02) reduction effect should desirably be monitored by the confirmer of the energy-saving effect. It is therefore realistic for the KESC to do so.
Regarding the method of verification of the C02 reduction effect, it is desirable to measure the density of the C02 emissions directly, but some difficulties are anticipated from the technological and economic viewpoints. Therefore, it is realistic to calculate it from the fuel consumption calculated for verification of the energy saving effect using the method mentioned in the Paragraph 2.3 of this Chapter. For the method of calculating the energy saving effect, refer to the Paragraph 1.4 of this Chapter.
3-13
3. Influence on productivity
3.1 Improvement of productivity
The energy saving effect and the greenhouse gas (C02) reduction effect that we have so far studied are the result of consideration on condition that the energy level to be produced remains constant before and after the project. This means that the energy saving effect and the greenhouse gas (C02) reduction effect described in the preceding section will be achieved without affecting the generated energy.
Another effect that the power stations can expect is that updating the aged gas turbines will alleviate work for operation and repairs, not only the improvement of the operational performance. This makes it possible to increase productivity, by means such as reduction workers, shortening work time, and cutting running costs.
On the other hand, in view of the chronic shortage of power in Karachi and the high frequency of resulting outages, the KESC wishes strongly to have its power generation increased as much as possible. In view of the future increase in power demand due to economic development and life enhancement, increasing the output of the gas turbine power stations and extending the running time are unavoidable. However, if the current equipment is to run for longer hours, the production of carbon dioxide, a greenhouse gas, will increase even further. Implementing this project and running a set of power plants with less C02 emissions at a lower fuel consumption will considerably help develop the industry and economy of Karachi and its surroundings. Productivity in these regions will presumably thus be greatly enhanced thanks to this project.
3.2 Reduction of energy consumption rate
Data from our survey of the power stations indicates that the fuel expenses per unit generated energy (in kWh) for the last fiscal year (July, 1999 through June, 2000) are 220-240 Paisa per kWh (100 Paisa are 1 Rupee, 1 Rupee is about 2 Yen). If this project is implemented, calculations based on the generated power during the last fiscal year indicate a cut of at least 30% in fuel consumption as described in clause 1.3. Trial calculations indicate such cuts to be achieved after the project are expected to be as large as 155 Paisa per kWh.
3-14
Chapter 4 Profitability
It is described in this chapter that the profit of KESC is expected to obtain when this project is made a reality. The section about the economic effect of the return on investment will set conditions for a case when this project is financed by special environmental yen credit and will describe the results of a study of the increment in the profit from the initial investment. The section about the cost-effectiveness of the project will describe the cost-effectiveness of the project, as determined by the energy-saving effect calculated in Chapter 3 and the greenhouse gas (C02) reducing effect.
1. Economical effect of the collection on investment
The return effect on investment is studied as the below two points.
(1) Profit and loss calculation
The return on investment is evaluated by calculating the increment in the profitproduced when the project is implemented (the profit achieved after depreciation).The method of evaluation is as follows.
(D The obtained profit increase is settled when the project is implemented.
(D Project implementation period and depreciation period is settled. Project implementation period is chose the longer period between the repayment and depreciation one, or the more.
(D In the project implementation period, the sum of the balance obtained by subtracting the depreciation cost and interest from the increment in the profit obtained during the depreciation period when the project is made a reality.
(2) Cash flow
The term on investment is evaluated by calculating the increment in the profit produced when the project is implemented. The method of evaluation is as follows.
(D The below settled condition is as the same as the case of (1)
(2) The sum of the balance obtained by subtracting the depreciation cost and interest from the increment in the profit obtained during the depreciation period when the project is made a reality.
® In the project implementation period, the sum of the balance obtained by subtracting the depreciation cost and interest from the increment in the profit obtained during the depreciation period when the project is made a reality.
4-1
1.1 Prerequisites
The prerequisites for the calculations are set as follows:
(1) Initial investment
The initial investment for implementing the project is set as follows, regarding the two cases presented in clause 2.4 in Chapter 2:
(Case 1:) (Unit: 1,000 dollars) (Case 2:) (Unit: 1,000 dollars)Gas turbines (9 units) 67,500 Gas turbines (9 units) 67,500Generators (9 units) 9,000 Generators
(9 units, rewound)4,500
Auxiliaries and others 7,500 Auxiliaries and others 6,000Total 84,000 Total 78,000
(2) Additional expenses
1) Profit and loss calculation
Additional expenses to be required to implement the project are limited to the depreciation costs and interest for the installation of the new equipment (Case 1: gas turbines and generators, Case 2: gas turbines). It is assumed that there are no changes in the running and maintenance costs before and after the project.
2) Cash flow
Additional expenses to be required to implement the project are limited to the initial cost and interest for the installation of the new equipment. 3
(3) Additional profits
Additional profits to be obtained from the project will stem only from the reducing effect of fuel expenses by the increase in efficiency described in clause 1.3 in Chapter 3. Similarly to the prerequisites described in clause 1.2 of Chapter 3, it is assumed that there will be no changes in the power output before and after the project and that there are no raise in the incomes from electric power charges.
The reduction in fuel expenses is determined directly by operational data about the two power stations obtained at the time of the field survey. The specific values are presented in Tables 1.3-1 through 1.3-8 of Chapter 3. As the fuel expenses, we will use the values listed below which were described in 1.2 of Chapter 1.
Natural gases: 178.56 Rs./MCF (2.98 $/MCF)
HSDO: 14.33. Rs./Litter (0.239 $/Litter)
The reduction effect in fuel expenses is no change in the depreciation period, and is decreased as 0.5% per year after that.
(4) Fund-raising
The initial investment indicated in (1) is financed by special environmental yen credit. The 15% of the initial investment will be financed by the country's own funds, and the remaining 85% by loans from special environmental yen credit, according to the loans regulations. The repayment period is 40 years according to the regulations for special environmental yen credit (the first 10 years are payment for only the interest, and the last 30 years are payment for the initial and interest) and at an interest rate of 0.75%.
(5) Depreciation
The new equipment is depreciated over 15 years, by a specified amount every year.It is assumed that depreciation is over for the installed equipment and it no longer has any value as an asset.
(6) Other
Calculations will be in terms of U S. dollars and it is assumed that there will be no changes in exchange rates and fuel expenses.
Table 1.1.1 show the values based on the aforementioned settings.
Table 1.1-1 Data Sources of Project EstimationsItem Unit Case 1 Case 2
Initial investment cost 103$ 84,000 78,000Special Environmental Yen Loan 103$ 71,400 66,300
ExpenditureDepreciation period Years 15 15Payment period for loan Years 40 40Interest ral:e of loan % 0.75 0.75
Reduction of fuel costNatural gas 103$/year 8,021 7,147HSDO 103$/year 139 139Total 103$/year 8,160 7,286
1.2 Calculation results
(1) Profit and loss calculation
Table 1.2.1 shows the calculation results of the profit and loss in Case 1, and Table 1.2.2 shows that in Case 2. According to the payment rule of Special Environmental Yen Credit, the payment is only an interest (0.75%) of loan (85% of initial cost) for first 10 years, and not decreased. Therefore, the profit is constant for this 10 years and increases from 11th year and more increases after the depreciation period (15 years).
Each Case 1 and Case 2, it is impossible to return the initial cost within the depreciation period. It is possible to return after 7 years, namely 22 years after the project confirmation.
(2) Cash flow
Table 1.2.3 shows the calculation results of cash flow in Case 1, and Table 1.2.4 shows that in Case 2. In each Case 1, and Case 2, it is possible to return the initial cost. After 23 to 25 years, it is possible to earn the same rate of the initial cost.
According to the above calculation results, it is the return investment period those 20 years after the project execution in this case. At that period, it is expectable to do a major overhaul as the gas turbine replacement, etc.
4-4
Table 1.2-1 Profit Estimation of the Rehabilitation Project
(Profit and Loss Chart, Case 1)
Fiscalyear
InitialCost
(103$)
Fuel reduction cost (103$)
Depletion(103$)
Interest(103$)
Profit(103$)
CumulativeProfit(103$)
-1 78,000 -78,0001 7,286 5,200 497 1,589 -76,4112 7,286 5,200 497 1,589 -74,8233 7,286 5,200 497 1,589 -73,2344 7,286 5,200 497 1,589 -71,6455 7,286 5,200 497 1,589 -70,0566 7,286 5,200 497 1,589 -68,4687 7,286 5,200 497 1,589 -66,8798 7,286 5,200 497 1,589 -65,2909 7,286 5,200 497 1,589 -63,701
10 7,286 5,200 497 1,589 -62,11311 7,286 5,200 481 1,605 -60,50712 7,286 5,200 464 1,622 -58,88513 7,286 5,200 448 1,638 -57,24714 7,286 5,200 431 1,655 -55,59215 7,286 5,200 414 1,672 -53,92016 7,250 398 6,852 -47,06817 7,213 381 6,832 -40,23618 7,177 365 6,813 -33,42419 7,141 348 6,793 -26,63020 7,106 332 6,774 -19,85621 7,070 315 6,755 -13,10122 7,035 298 6,736 -6,36523 7,000 282 6,718 35324 6,965 265 6,699 7,05325 6,930 249 6,681 13,73426 6,895 232 6,663 20,39727 6,861 215 6,645 27,04228 6,826 199 6,627 33,67029 6,792 182 6,610 40,27930 6,758 166 6,593 46,87231 6,724 149 6,575 53,44732 6,691 133 6,558 60,00633 6,657 116 6,541 66,54734 6,624 99 6,525 73,07235 6,591 83 6,508 79,58036 6,558 66 6,492 86,07137 6,525 50 6,476 92,54738 6,493 33 6,459 99,00639 6,460 17 6,444 105,45040 6,428 0 6,428 111,878
Table 1.2-2 Profit Estimation of the Rehabilitation Project
(Profit/Loss Chart, Case 2)
Fiscal Initial Fuel reduction Deple- Interest Profit Cumulativeyear Cost cost (103$) tiation (103$) (103$) Profit
(103$) (103$) (103$)
-112
J345678 9
10111213141516 17 ]81920 21 22232425262728293031323334353637383940
78,0001,5891,5891,5891,5891,5891,5891,5891,5891,5891,5891,6051,6221,6381,6551,6726,8526,8326,8136,7936,7746,7556,7366,7186,6996,6816,6636,6456,6276,6106,5936,5756,5586,5416,5256,5086,4926,4766,4596,4446,428
-78,000-76,411-74,823-73,234-71,645-70,056-68,468-66,879-65,290-63,701-62,113-60,507-58,885-57,247-55,592-53,920-47,068-40,236-33,424-26,630-19,856-13,101
-6,365353
7,05313,73420,39727,04233,67040,27946,87253,44760,00666.547 73,072 79,580 86,07192.547 99,006
105,450111,878
-4-6-
Table 1.2-3 Profit Estimation of the Rehabilitation Project(Cash Flow Chart, Case 1)
Fiscalyear
InitialCost
(10%
Fuelreduction
cost (103$)
Principal(10%
Interest(10%
Profit(10%
CumulativeProfit(10%
-1 66,300 -66,3001 7,286 497 6,789 -59,5112 7,286 497 6,789 -52,7233 7,286 497 6,789 -45,9344 7,286 497 6,789 -39,1455 7,286 497 6,789 -32,3566 7,286 497 6,789 -25,5687 7,286 497 6,789 -18,7798 7,286 497 6,789 -11,9909 7,286 497 6,789 -5,201
10 7,286 497 6,789 1,58811 7,286 2,210 481 6,805 8,39312 7,286 2,210 464 6,822 15,21513 7,286 2,210 448 6,838 22,05314 7,286 2,210 431 6,855 28,90815 7,286 2,210 414 6,872 35,78016 7,250 2,210 398 6,852 42,63217 7,213 2,210 381 6,832 49,46418 7,177 2,210 365 6,813 56,27619 7,141 2,210 348 6,793 63,07020 7,106 2,210 332 6,774 69,844
Table 1.2-4 Profit Estimation of the Rehabilitation Project (Cash Flow Chart, Case 2)
Fiscalyear
InitialCost
(10%
Fuelreduction
cost (10%
Principal(10%
Interest(10%
Profit(10%
CumulativeProfit(10%
-1 66,300 -66,3001 7,286 497 6,789 -59,5112 7,286 497 6,789 -52,7233 7,286 497 6,789 -45,9344 7,286 497 6,789 -39,1455 7,286 497 6,789 -32,3566 7,286 497 6,789 -25,5687 7,286 497 6,789 -18,7798 7,286 497 6,789 -11,9909 7,286 497 6,789 -5,201
10 7,286 497 6,789 1,58811 7,286 2,210 481 6,805 8,39312 7,286 2,210 464 6,822 15,21513 7,286 2,210 448 6,838 22,05314 7,286 2,210 431 6,855 28,90815 7,286 2,210 414 6,872 35,78016 7,250 2,210 398 6,852 42,63217 7,213 2,210 381 6,832 49,46418 7,177 2,210 365 6,813 56,27619 7,141 2,210 348 6,793 63,07020 7,106 2,210 332 6,774 69,844
4-7
2. Cost effectiveness of the project
2.1 Prerequisites
The values of the energy-saving effect and the greenhouse gas (C02) reducing effect in this project are as described in 1.3 and 2.3 of Chapter 3.
The initial investment for this project is as described in 1.1 of this chapter. These are the basis for calculating the cost-effectiveness of Cases 1 and 2. Cost-effectiveness was calculated in terms of U S. dollars and yen, and the exchange rate of the yen was set to 110 yen against the dollar.
2.2 Calculation results
The calculation results are summarized in Table 2.2.1.
Table 2.2-1 Initial Cost Performance on Effects through the Project
Item Unit Case 1 Case 2
Initial investment cost o 84,000 78,000
Energy saving effect toe/y 64,900 57,900
C02 reduction effect t-C02/y 200,800 179,100
Costperformance
Energy savingtoe/y/103$ 0.77 0.74
toe/y/106¥ 8.50 8.17
C02 reductiont-C02/y/103$ 2 39 2 30
t-CO2/y/106¥ 26 3 25 3
The reason why Case 2 is lower in the energy-saving effect and the C02 reducing effect than Case 1 is that, as described in 1.2, the generator capacity is so small that the gas turbines must be run at partial load, resulting in a higher specific fuel consumption than in Case 1.
The present study sets conditions for simplifying the calculation of profits. When assessing the profits from the project, one should consider the following:
1) Details of the initial investment
2) Changes in the operational status
Relationship between the increase in incomes from power charges due to higher output and the effect of saving fuel expenses
Running cost
4-8
3) Changes in the economic situation [such as commodity prices (particularly fuel expenses), import duties, and exchange rates]
Besides the gas turbine power plants, KESC owns steam thermal power plants.Like many of the gas turbine power plants, many of the steam thermal power plants are more than 15 years old and need rehabilitation.
In Chapter 5, it is described in detail that the energy-saving effect and the greenhouse gas (C02) reducing effect of the steam thermal power plants. It seems that rehabilitation produces even higher effects. Here are the reasons:
1) Steam thermal power plants are larger in scale than gas turbine ones, thus having higher absolute values of emissions of greenhouse gases (C02).
2) Records of previous regular inspections reveal that some of the thermal power plants have declined much in output and power generation efficiency, which allows us to expect considerable effects of energy-saving and greenhouse gas reduction from rehabilitation.
It have not yet been assessed the initial investment required for rehabilitating the steam thermal power plants, because they are not covered in the scope of our present survey. However, if we can rehabilitate the steam thermal power plants at the same time as we do the gas turbine ones, we will be able to save expenses for transportation, work and other operations, of all the initial investment expenses on the steam thermal power plants, thus increasing cost-effectiveness even further.
It is believed that the project should cover the steam thermal power plants as well and that they should be considered similarly to the gas turbine power plants.
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Chapter 5 Verification of the progress effect
It is considered that the two cases presented below in terms of the possibility of spreading the energy saving and greenhouse gas reduction technologies to other facilities.
(1) The spreading of Case 1 presented in clause 2.4 of Chapter 2 (replacement of the gas turbines and generators) to gas turbine power plants owned by electric power companies other than the KESC
(2) The spreading of thermal power plants owned by the KESC
In each case, some power plants are selected and surveyed the present condition, and assessed the energy saving and the greenhouse gas reduction effect quantitatively.
1. Possibility of the progress in the country to introduce the objective technology by the project
1.1 Overview of the progress possibility regions
(1) Gas turbine power plants in other regions
The KESC is an electric power company specializing in supplying electric power to Karachi. It does not own any other gas turbines that are covered in our present survey. However, WAP DA in charge of the KESC owns many gas turbines and combined cycle power stations in Pakistan. Pakistan also has IPP-owned gas turbines and combined cycle power plants.
Table 1.1-1 presents the main gas turbines (except for those under construction or planning) owned by WAPDA, and Table 1.1-2 those owned by IPPs. For the combined-cycle plants, the tables only indicate the gas turbine outputs (except for the outputs of the steam turbines).
The tables show in shaded patterns the gas turbines of scales comparable to the gas turbines in the power stations covered in our present survey and which we believe can accommodate the technology covered in this project.
Some of the WAPDA-owned gas turbines are as old as those in the power stations covered in our present survey. They are therefore presumed to have similar problems. As an example, FAISALABAD PS is selected and surveyed because this PS has the most gas turbines and seems to be likely to get the high progress effect.
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Table 1.1-1 Gas Turbine Power Stations of WAPDA
Name Cycle Unitnumber
Installed capacity (MW)
Commercialoperation
Per unit Total
QUETTA Simple
2 7.5 15 19641 7 7 19721 12 12 19751 mmzsmim 19751 35 35 1984
SHAHDRA Simple 2 13.25 26.5 19664 14.75 59 1968,1969
KOTRI Simple 2 15.0 30 1970■k 26.5 106 1975.1983
FAISALABAD Combined ^;^T4k:::vV & : w. 106 1975Simple :::T t25:07:# 100 1975
MULTAN Simple 4 65.0 260 1985
GUDDUCombined 2 136 272 1986,1993
Simple 4 100 400 19862 136 272 1989
Table 1.1-2 Gas Turbine Power Stations of IPP
Name Owner Cycle Unitnumber
Installed capacity (MW)
CommercialOperation
Perunit Total
GOTHMACCHI Fauji Fertilizer
Simple 2 18 36 1982
BIN QASIM JORDAN Simple 2 26.3 52.6 1997
DAHRKI ExxonPakistan Simple 2 10.75 21.5 1969,1970
HABIBULLAHCOASTAL
CoastalPower Combined 3 40 120 1999
KABIRWARA Fauji Electric Power Combined 2 49 98 1999
KORANGIBARGE
WestmontIndustriesBHD
Combined 4 48 192 1998
KOT ADDUKot AdduPower Co. (KAPCO)
Combined4 95 380 1987
6 100 600 1994,1995
PAKCHINAHARIPUR
Schon Power GenerationLtd.
Simple 1 15 15 1997
ROUSCH RouschPower Ltd Combined 2 150 300 1999
5-2-
(2) Thermal power plants
As described in (1), KESC is an electric power company specializing in supplying electric power to Karachi. KESC has no gas turbines other than those covered in our present survey.
Table 1.1-3 presents the thermal power plants owned by the KESC.
Table 1.1-3 Power Stations of KESC
Stationname
Turbinetype
UnitNo.
CommerciaI operation
Maximum power generation (MW)
Design 1999BINQASIM
Steam 1 1983 210 1902 1984 210 1903 1989 210 904 1990 210 1405 1991 210 1506 1997 210 200
Tota - 1,260 960KORANGI Steam 1 1966 66 25
2 1966 66 03 1970 125 904 1977 125 85
Tota - 382 200KORANGI Gas 1-4 1979 100 70SITE Gas 1-5 1980 125 80
Total - 1,867 1,310
Every thermal power plant is located in an industrial zone within 50 km from the center of Karachi and indispensable in the supply of electric power to Karachi and its peripheral industrial zones. The steam thermal power plants in BIN QASIM and KORANGI produce the electric power at least 85% of the total power capacity of the KESC.
The thermal power plants are operated more than ten years. Some of them are even more than 30 years. Not only the gas turbine power plants but the thermal power plants as well have such degradation problems of output and efficiency. Regarding these thermal power plants, it is studied that the energy saving and the greenhouse gas reduction effect from the rehabilitation of the boilers and turbines.
-5-3
FAISALABAD PS consist of a total of eight gas turbines: four simple cycle units (25 MW) and four combined cycle units (26.5 MW). The gas turbine power plants achieve a total output of 206 MW, to which the steam turbine having an output of 44.4 MW is added. The power station achieves a total output of 250.4 MW.
The gas turbines were manufactured by AEG of Germany. They were put into operation in 1975, similar to the dates of operation start-up of KORANGI GT PS (put into operation in 1978) and SITE GT PS (put into operation in 1979) covered in our present survey.
Our survey revealed the following:
1) The thermal power plants are periodically repaired in the repair workshop next-door.
2) The thermal power plants have declined in output and power generation efficiency due to secular deterioration. They now have an output of about 70% of that when put into operation, and have declined in power generation efficiency by about 5%.
3) The operation pattern is similar to other power stations: The plants run during the time zone in the evening when power demand is high.
Gas turbines of FAISALABAD PS were put into operation at dates similar to the gas turbines in the gas turbine power plants covered in our present survey. Their operation patterns are similar as well. They also share similar problems. The technologies for energy-saving and reduction greenhouse gases which we studied in our present survey are therefore applicable.
(2) Thermal power plants
The thermal power plants at BIN QASIM and KORANGI (hereinafter referred to as "the two thermal power plants") are located in the seashore region about 50 km from the center of Karachi. As described in 1.1, the two thermal power plants account for at least 85% of the total power capacity of the KESC. The two thermal power plants run almost throughout the day at peak brake power, except for some of the equipment, and they are indispensable in supplying electric power to Karachi.
As shown in Table 1.1-3, most of the thermal power plants are more than ten years old, thus suffering such problems as lowered output and power generation efficiency.
Previous periodic inspections reveal that rehabilitating the boilers and turbines will increase output and power generation efficiency. The energy-saving effect and the greenhouse gas reduction effect increase as output rises. We therefore studied the application of the technology covered in this report to the thermal power plants.
For the details of the rehabilitation of the thermal power plants, see the survey report listed in the References, entitled "Feasibility Study on Rehabilitation of KESC’s Thermal Power Plants"
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2. Effect under consideration of progress
2.1 Energy saving effect
(1) Gas turbine power plants
1) Prerequisites
The conditions required for a study of the energy-saving effect are as described in detail in clause 1.1 and 1.2 of Chapter 3. For FAISALABAD PS, it is set that the additional conditions as listed below.
1) The considered configuration is four simple cycle gas turbines (25 MW).
2) The cases to be studied are limited to Case 1 presented in clause 2.4 of Chapter 2 (replacement of the gas turbines and generators).
3) It is assumed that the current total output of the four gas turbines is reduced to 75% (75 MW) of the design value (100 MW), with the thermal efficiency reduced by 5%.
4) The running time of the gas turbines is 6 hours per day (18:00 to 24:00), and 2,000 hours per year. That is, each gas turbine will achieve an annual power rate (kWh) as follows:
25,000(kW) x 0.75 x 2,000(h) = 37,500,000(kWh)
5) The fuel is limited to natural gas. The characteristics of the gas, including its calorific value, are the same as those of the two GT PS at KORANGI and SITE.
6) The operational conditions assuming the replacement include an atmospheric temperature of 20°C in view of the climate of Faisalabad. At that time, the latest- model gas turbines will achieve an output of 26,060 kW, and a thermal efficiency of 32.74%.
2) Study results
- Before the project
1) Table 2.1-1 shows the fuel consumption in terms of crude oil, as calculated on the basis of the generated power set under the prerequisites listed in 1).
- After the project
Table 2.1-1 indicates the fuel consumption rates required to produce the same power rates as before the project with the latest-model gas turbines.
Table 2.1-2 compares the energy-saving effects achieved before and after the project as determined by Table 2.1-1. After the project, higher thermal efficiency is projected to save annual fuel consumption by about 18,000 tons (31.6%) in terms of crude oil. Assuming that the observed period of the effect is 15 years, we will in the meantime save about 270,000 tons in terms of crude oil.
5-6
Our present study covered four simple-cycle gas turbines (25 MW) under the same conditions as the gas turbine power plants covered in our survey. However, FAISALABAD PS contains four combined cycle gas turbines (26.5 MW). If this project is to cover these as well, it will be even more effective.
5-7
Table 2.1-1 Energy Saving and CO2 Reduction of Replacing Existing Gas Turbines by Latest Gas Turbinesfor Propagation to FAISALABAD PS
Item Units
Before Execution of ProjectAfter Execution
of ProjectAdvantages
Existing Gas Turbine Latest Gas Turbine (4units)Unit No.1 Unit No.2 Unit No.3 Unit No.4 Total
Unit Generated Gas kWh 37,500,000 37,500,000 37,500,000 37,500,000 150,000,000 150,000,000
Oil kWh - - - - 0 -
Total kWh 37,500,000 37,500,000 37,500,000 37,500,000 150,000,000 150,000,000
Fuel Consumption Gas MCF/y 601,000 601,000 601,000 601,000 2,404,000 1,645,500 758,500
Oil Lit./y - - - - - - -
Heat Consumption Gas GJ/y 602,387 602,387 602,387 602,387 2,409,546 1,649,296 760,250
Oil GJ/y - - - - - - -
Total GJ/y 602,387 602,387 602,387 602,387 2,409,546 1,649,296 760,250
Gross Heat Rate kJ/kWh 16,064 16,064 16,064 16,064 16,064 10,995
BTU/kWh 15,225 15,225 15,225 15,225 15,225 10,422
Gross Plant Efficiency % 22.41 22.41 22.41 22.41 22.41 32.74
Equivalent Calorific Value of Crude Oil
kJ/kg 41,868 41,868 41,868 41,868 41,868 41,868
Equivalent Consumption of Crude Oil
t/y 14,388 14,388 14,388 14,388 57,551 39,393 18,158
Equivalent Amount of Crude Oil
toe/y 14,388 14,388 14,388 14,388 57,551 39,393 18,158
Annual CO2 Emission t-COz/y 44,519 44,519 44,519 44,519 178,075 121,890 56,185
Note; (1) The data of item number 1 through 4 for existing gas turbines are assumed for analysis of propagation to FAISALABAD PS.(2) Total generated power (MWh) of latest gas turbines is assumed to be the same as that of existing gas turbines No.1~No.4.(3) Gas turbine performance is based on the ambient temperature of 20 °C to apply the climate of FAISALABAD.(4) Regarding the heating values for fuel gas, standard value of KESC are also applied.
Natural gas : 950 BTU/MCF(5) Annual C02 Emission (t-C02/y)=Equivalent amount of crude oil (toe/y)/1000 x 42.62 x 20 x 0.99 x (44/1 2)
(Source: "Greenhouse gas emission calculation guideline" issued by the Japanese Government)
Table 2.1-2 Summary of Energy Saving and CO2 Reduction Effect for Propagation to FAISALABAD PS
Item UnitsBefore
Execution of Project
After Execution of Project
ReductionEffect
Remarks
Equivalent Consumption of Crude Oil
t/y 57,551 39,39318,158
( 31.6%)
AnnualEquivalent Amount
of Crude Oiltoe/y 57,551 39,393
18,158 ( 31.6% )
CO2 Emission t~C02/y 178,075 121,89056,185
( 31.6% )
Equivalent Consumption of Crude Oil
t 863,265 590,891272,374 ( 31.6% )
15 Years *1)
Equivalent Amount of Crude Oil
toe 863,265 590,891272,374 ( 31.6% )
CO2 Emission t-C02 2,671,126 1,828,343842,782 ( 31.6% )
Note *1) Annual generated power is assumed to be the same as that of first year during 15 years.
(2) Thermal power plants
1) Prerequisites
In calculating the energy-saving effect of the thermal power plants, we set the following prerequisites:
1) The units to be rehabilitated will be Units 1 through 5 in the BIN QASIM PS and Units 3 and 4 in the KORANGI PS.
2) Before and after the project, the plants produce the same amount of electric power. Power production before the project is calculated on the basis of the peak brake power of 1999 shown in Table 1.1-3 in clause 1.1 of this chapter.
3) The improving effect of the power generation efficiency by rehabilitating the thermal power plants is as indicated below.
Increase (%) in power generation efficiency = (boiler efficiency (%) x turbine efficiency (%) (after the project))
- [boiler efficiency (%) x turbine efficiency (%) (before the project)]
4) Including the increase in efficiency indicated in 3), the values required for the calculations will be set as shown in Table 2.1-3.
Table 2.1-3 Factors required for the calculations
Power station BIN QASIIV KORANGIUnit No. 1 2 3 4 5 3 4
Output (MW) 190 190 90 14
0150 90 85
Annual avai ability (%) 70 70Before the project
Boiler efficiency (%) 75 75 70 70 70 70 70Turbine efficiency 36 36 30 35 36 30 30
After the project
Boiler efficiency (%) 80 80Turbine efficiency 40 40
Increase in power efficiency (%) 5.0 5.0 11.0 7.5 6.8 11.0 11.0
The energy saving effect is calculated as follows, using the values presented in the "Guideline for the Calculation of Greenhouse Gas Emissions."
Energy saving effect = output (kW) x increase in power generation efficiency (%)as oil equivalent (toe/y) /100 x 24 x 365 x annual availability (%) / 100 x 2,646/10,000/1,000
2) Study results
Table 2.1-4 shows the calculation results of the energy saving effect using the values indicated in Table 2.1-3.
5-10
Table 2.1-4 Calculation results of the energy-saving effect
Power station BIN QASIM KORANGIEquipment (Unit No.) 1 2 3 4 5 3 4Electric power increase (X107 kWh/y) 5.82 5.82 6.07 6.44 6.25 6.07 5.73
Energy saving effect (toe/y) 15,400 15,400 16,060 | 17,040 16,540 16,060 15,170Energy saving effect (total, toe/y) 80,440 31,230
The energy saving effect of the two power stations will amount to about 111,700 tons of savings per year in terms of crude oil. Comparing this value with the results of clause1.3 of Chapter 3 and this clause (1) reveal that the energy-saving effect of the steam thermal power plants is higher than that of the gas turbine thermal power plants. In the present survey, the increase in efficiency is an estimate, but an elaborate survey regarding steam thermal power is expected to produce an even further energy-saving effect.
2.2 Greenhouse gas reduction effect
(1) Gas turbine power plants
1) Prerequisites
The production of greenhouse gases accompanies the combustion of fuels, and is indivisible from the energy-saving effect. The prerequisites described in clause 2.1 will therefore apply.
As the formula for calculating the annual emissions of C02, it is used that the formula indicated in the "Guideline for the Calculation of Greenhouse Gas Emissions" presented in the References.
Oil equivalent (toe/y) 44C02 equivalent (t-C02/y)=------------------------------ x 42.62 x 20 x 0.99 x ---------
1,000 12
2) Study results
Before the project
As the study results before the project, we will use Table 2.1-1 used in studying the energy saving effect of clause 2.1. The table indicates the production of C02 calculated with the aforementioned formula.
After the project
We calculated the production of carbon dioxide on the basis of the fuel consumption required to produce the same power rate as before the project with the new-model gas turbines. Table 2.1-1 shows the calculation results. The C02 reduction effects before and after the project are shown in Table 2.1-2 presented above.
5-11
Our present survey covered four simple-cycle gas turbines (25 MW) under the same conditions as the gas turbine power plants covered in the survey. However, FAISALABAD PS contains four combined cycle gas turbines (26.5 MW) and one steam turbine (44.4 MW). If these are to be covered as well, the effect of such efforts will be even higher.
After the project, the annual production of C02 can be saved by about 56,000 tons(31.6%). Assuming that the observed period of the effect is 15 years, the C02reduction effect in the meantime will be a saving of about 840,000 tons.
(2) Thermal power plants
1) Prerequisites
The thermal power plants use fuels similar to those in the gas turbines. The prerequisites are therefore identical with those in the case of (1).
2) Study results
Table 2.1-5 shows the result of calculating the C02 reduction effect using the values shown in Table 2.1-4 in clause 2.1.
Table 2.1.5 Calculation results of the C02 reduction effect
BIN QASI M KORANGIEquipment (Unit No.) 1 2 3 4 5 3 4Energy-saving effect (toe/y) 15,400 15,400 16,060 17,040 16,540 16,060 15,170C02 reduction effect (t-C02/y) 47,650 47,650 49,690 52,730 51,180 49,690 46,940C02 reduction effect (total, t-C02/y) 248,900 96,630
The carbon dioxide reduction effects of the two power stations will be a cut by about 345,500 tons per year. Comparing this value with the results of clause 2.3 of Chapter 3 and those of this section (1) reveals that the C02 reduction effect of steam thermal power is higher than gas turbine thermal power. In the present survey, the increase in efficiency is an estimate, but an elaborate survey regarding steam thermal power is expected to produce an even further C02 reduction effect.
5-12
Chapter 6 Influence on other sectors
In the implementation of the project, setting up effective supply resources for natural gas in Pakistan is a challenge. This chapter describes the current supply status of natural gas and its future challenges.
These days, the Pakistani Government is strongly implementing a policy of switching the fuel used in its thermal power plants from fuel oil to natural gas. Here are the reasons:
1) Pakistan relies on imports for most of its fuel oil. The price hikes of fuel oil due to the recent skyrocketing prices of crude oil have increased the debts of the Pakistani Government, placing a strain on its finances.
2) Natural gas is available at home. It does not change much in pricing and is cheap.
3) A pipeline has been laid from the production sites in the north to the consumption areas in the south, enabling the supply of natural gas.
Another reason for the government's switch from fuel oil to natural gas is that fuel oil contains much sulfur (3.5%), so that air pollution in and around the cities is becoming serious. Here are the details of the status.
1. Natural gas product1.1 Background
The development of natural gas in Pakistan has been undergoing steady growth. In 1999, natural gas accounts for 38% of the total supplies of major energy sources. Gas production and consumption have been rising about 5% each year for the past six years.
Table 1.1-1 indicates the status of the major natural gas fields in Pakistan. Most of the natural gas fields discovered in Pakistan during the past few years are the Kirthar region and the Lower Indus Basin in the province of Sindh.
The newly discovered natural gas fields are in the deepest recesses of the existing natural gas fields such as Mari and Sui. Some small natural gas fields have also been discovered.
6-1
Table 1.1-1 Major gas fields
Gas Field Discovery
Reserves (TCF)1 Production(1999)
(MMCFD)*2
HeatingValue
(BTU)*3RemarksOriginal Remaining
Sui 1951 9.6 2.6 836 925 Operated by PPL.Convertible to 980 Btu after processing.Decline expected by 2002.
Pirkoh 1975 1.50 0.71 106 898 Operated by OGDC.Future production level is uncertain.
Loti 1984 0.29 0.127 44 851 Operated by OGDC.
Dhodak 1975 0.623 0.55 50 1,030 Operated by OGDC.Recent indications are that production can be significantly increased.
Kadanwari 1989 0.17 0.070 70 950 Operated by LASMO.Rapid decline was expected but recent sharing of facility with Miano has made production more economical. Short-term production boost to 87 MMCFD is possible.
Qadirpur 1990 2.8 2.45 207 890 Operated by OGDC.Recent study indicates that reserves could be as high as4 TCF.
Mari 1956 6.3 4.26 383 740 Operated by MGCL. Major supplier to fertilizers
NorthernArea
95 Numerous small fields in the Potohar area produce high calorific gas.Current production is expected to decline.
Badin 161 Numerous small fields inBadin area of SouthernSindh, operated by UnionTexas and OGDC.
*1: Trillion Cubic Feet *2: Million Cubic Feet per Day *3: British Thermal Unit
6-2-
1.2 Natural gas production capacity
Table 1.2-1 shows production capacity projections for 2005 presented by the Gas Development Public Corporation.
Table 1.2-1 Overall gas production potential
Region 1999 Estimate (MMCFD)
2005 Estimate (MMCFD)
North 463 510Center 897 952South 1,203 1,006Total 2,563 2,468
On a regional basis, the corporation expects a rise in production capacity due to the discovery of the new fields (the Qadirpur natural gas field in the north and the deepest recesses of the Sui natural gas field in the middle). The south is expected to see a decline in production capacity because the production projections of the Miano and Sawan gas fields have been revised downwards.
1.3 Natural gas production
Table 1.3-1 shows the production quantities of the natural gas fields in years up to fiscal 2000 and the production projections in and after fiscal 2001.
For each natural gas field, production projections are presented according to the stockpile. The projections in the table are from the report by Beicip Franlab of the Asian Development Bank (ADB).
The production projections indicate that Pakistan's production of natural gas will peak in fiscal 2004, decline gradually after fiscal 2004, and go back to the fiscal 2000 level in fiscal 2010.
However, these predictions are for the natural gas fields discovered so far. It is highly likely that undiscovered natural gas fields will be developed in the future. The Pakistani Government aims to increase production by offering incentives to explorers of natural gas.
-6-3-
Table 1.3-1 Natural gas supply (MMCFD)
Gas Field 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010
Sui 600 688 688 679 674 638 558 456 369 306 266 225
Pirkoh 100 142 143 134 130 130 125 121 78 68 64 53
Kadanwari 70 62 62 45 26 9 5 5 0 0 0 0
Daro 10 10 10 6 5 4 3 2 1 1 1 1
Badin (S) 179 167 167 221 213 194 151 115 103 80 60 44
Qadirpur 238 315 315 360 360 360 360 360 360 360 360 360
Dakhni 17 17 17 17 17 17 16 15 14 13 12 9
Dhodak 36 36 45 45 45 45 45 45 45 45 45 45
Loti 37 36 36 36 36 32 27 23 21 18 15 13
Dhumal 3 2 2 1 1 1 1 1 0 0 0 0
Ratana 6 5 4 3 3 2 2 1 1 1 1 1
Meyal 6 5 4 4 3 3 3 2 2 2 2 2
Pindori 14 14 13 12 12 11 10 9 7 6 5 5
Pariwali 10 15 13 12 12 10 8 7 7 6 5 5
Sadkal 10 9 8 7 4 1 0 0 0 0 0 0
Missakeswi 4 4 2 1 1 1 0 0 0 0 0 0
Adhi 18 18 18 17 17 17 17 17 17 17 17 17
Miano - - 90 90 90 90 90 90 90 63 54 45
Sawan (S) - - 0 0 54 126 126 126 180 180 180 180
Bhit - - 216 216 216 216 216 216 216 216 216 216
Zamzama - - 45 54 54 180 180 180 180 180 180 180
Bhadra - - 0 0 90 90 90 90 90 90 90 90
Zargam - - 0 0 54 54 54 54 54 54 54 54
Total 1,358 1,545 1,898 1,960 2,117 2,231 2,087 1,935 1,835 1,706 1,627 1,545
6-4
2. Natural gas utilization trends
2.1 Natural gas demand
(1) Current demand
Table 2.1.1 shows current demand for natural gas.
Table 2.1-1 Natural gas present demand (MMCFD)
Sector 1998 1999 2000Residential 420 464 494Commercial 45 59 64Industrial 340 356 365Fertilizer 143 187 222Power 250 279 664Line Losses 110 142 188Total Demand 1,308 1,487 1,997
Demand for natural gas for electric power more than doubled during fiscal 2000. Here are the presumable reasons:
1) The Pakistani Government was (and still is) guiding the industry to switch its fuel for electric power from oil to natural gas.
2) Demand for electric power was (and still is) on the rise due to the rise in power demand.
(2) Future demand
The Pakistani Government makes some projections for demand for natural gas in years up to 2010 as well. Table 2.1.2 shows those demand projections.
Table 2.1-2 Natural gas future demand (MMCFD)
Sector 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010
Residential 525 548 580 613 646 681 717 754 792 832Commercial 69 74 79 84 90 95 101 106 112 118Industrial 373 383 393 405 418 432 445 460 474 490Fertilizer 227 234 259 259 374 374 374 394 394 394Power 744 755 1,349 1,342 1,396 1,378 1,417 1,418 1,461 1,529Line Losses 179 164 199 194 200 213 221 227 235 243TotalDemand 2,117 2,158 2,859 2,897 3,124 3,173 3,275 3,359 3,468 3,606
The doubling of demand for electric power fiscal 2003 seems to be due to the Pakistani Government's guiding the electric power companies to switch to a different fuel in all their equipment by fiscal 2002.
— 6-5 —
3. Laying of natural gas pipelinesThe gas industry is guided by the Ministry of Petroleum and Natural Resources of the Pakistani Government. The Ministry of Petroleum and Natural Resources has been in charge of determining gas charges, regulations and other matters but its authority has been transferred to a recently established National Gas Regulatory Authority (GRA). The authority to lay pipelines also belongs to the GRA.
In Pakistan, natural gas is distributed from the natural gas fields in the middle to the consumption points in the north and south. Production and distribution of gas is administered by independent firms respectively.
3.1 Overview of the natural gas distributors
(1) Sui Northern Gas Pipelines Ltd. (SNGPL)
The SNGPL is Pakistan's largest gas distributor. It is headquartered in Lahore. It sells in the provinces of Punjab and NWFP. As of June, 1999, the company had 1,747,000 customers, of which 1,706,000 were households and the remaining were commercial and industrial customers.
The company has a 5,112km network of high-pressure gas pipelines, involving 12 boost stations, along with 29,954km of distribution mains and service pipes.
Fig. 3.1-1 shows the pipeline network of the SNGPL.
R.hiiYiyar M""''
Fig. 3.1-1 SNGPL pipeline network
-6-7-
(2) Sui Southern Gas Company (SSGC)
The SSGC is Pakistan's second largest gas distributor. It is headquartered in Karachi. It sells in the provinces of Sindh (including Karachi) and Baluchistan. As of June, 1999, the company had 1.45 million customers, of which 1.43 million were households and the remaining were commercial and industrial customers.
The company has a 2,764km network of high-pressure gas pipelines. Its main pipelines are the Indus Right Bank Pipeline and the Indus Left Bank Pipeline (which connect the supply sources of the company to Karachi and the province of Sindh) and the Quetta Pipeline (which connects the supply sources to the towns of Baluchistan). The distribution mains and service pipes are 21,080km long (as of June 30, 1999).
Fig. 3.1-2 shows the pipeline network of the SSGC.
India
Fig. 3.1-2 SSGC pipeline network
3.2 Installation of natural gas pipelines
The gas distributors are now laying new pipelines according to the Pakistani Government's policy of switching to a different fuel.
Natural gas has so far been assigned to households as something of high priority. These days, however, pipelines are being laid to connect the thermal power plants. These pipelines are then making it possible to supply gas to large thermal power plants (such as the BIN QASIM PS in Karachi and the KOTORI PS in Hyderabad) and cities.
The Pakistani Government wishes to lay a pipeline network in the major cities and at and around the large thermal power plants by the end of fiscal 2002 in an attempt to switch to a different fuel.
6-9
4. Future focus of natural gas utilizationThis section describes how natural gas is likely to be used in the field of electric power in the future. A task force on power generation through natural gas was set up in Pakistan and has presented a proposal based on the agreement of its members. Here is an overview of the proposal.
4.1 Background and history of the task force
To switch its fuel for power generation to gas, which is cleaner, is more efficient, and leads to foreign currency savings, the government is considering a methodology of assigning its homegrown gas resources to the country's electric power industry. Estimates indicate that Pakistan's imports of oil for power generation exceed 2.5 billion dollars per year.
Nine private electric power companies (with a total power generation capacity of 3,906MW) are now interested in switching their fuels from oil to gas. Gas demand is estimated at 933 MMCFD. Based on that, a task force was set up by private oil and gas firms, WAPDA, Private Power Improvement Board (PPIB), Oil & Gas Development Company (OGDC), IPPs and other establishments.
4.2 Proposal contents
The proposal made by the task force indicated the following:
1) The development of natural gas fields must be promoted soon to improve the Pakistani economy.
2) Domestic gas production must be increased from 2,000 MMCFD to 3,000 MMCFD during the next four years.
3) The projects of gas imports from Qatar, Iran and other countries must be accelerated.
The proposal made by the task force can be divided into three stages: short, medium, and longterm proposals.
(1) Short-term proposals (2001-2004)
The untapped large gas market that is the easiest to tackle on a short-term basis is that for electric power in the Multan and the Bin Qasim regions.
(a) The increment to the gas supplies to Bin Qasim will be 150-250 MMCFD. The increment to the gas supplies to Multan will be 100-200 MMCFD.
(b) The increment (150-200 MMCFD) to the gas supplies to Bin Qasim will be covered by new supplies from the natural gas fields of Miano, Zamzama, EWT, Bhit, and Sawan.
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(c) To supply gas to Bin Qasim, the SSGC will have to make an additional investment of about 16 million dollars in production and supply equipment.
(d) When the Phase II of the Qadirpur natural gas field and the development of the deepest recesses of the Sui natural gas field are in gear, the electric power project in the Multan region will be able to enjoy an additional supply of 100-150 MMCFD.
The capacity of pipeline transportation from Sui to Bhraf will be increased from 600 MMCFD to 700 MMCFD, while that from Bhraf to Multan will be increased from 1,000 MMCFD to 1,150 MMCFD. The cost for fulfilling that goal is estimated at 20 million dollars.
(2) Middle term proposals (2005-2010)
The requirement for the additional gas supply to the power station in the Multan region cannot be met even if the short-term proposals are implemented until 2005.
(a) A new pipeline having a capacity of 500-600 MMCFD must be built to Multan by 2005.
(b) This pipeline transports gas from Zamzama. The additional supply of gas will be procured from other existing natural gas fields, while new natural gas fields must be developed promptly.
(c) The following two scenarios are possible for the buildup of a new pipeline:
1) The SNGPL will built a new pipeline and supply gas to the Multan region.
2) An independent gas distributor other than the SNGPL will build a pipeline and supply gas directly from the Sindh natural gas field in the south.
(3) Long term proposals (after 2010)
A new network of gas pipelines must be developed to meet the short- and medium-term supply targets over a long term.
Pakistan is considered to have many untapped natural gas fields. Imports projects must be promoted at the same time. The following measures must be taken over a long term:
1) More flexible plans for exploration2) Rational pricing of gas3) Liberalization of gas business4) Promotion of gas imports projects
a) Gas imports from Qatarb) Gas imports from Iranc) Gas imports from the United Arab Emirates (UAE)d) Gas imports from Turkmenistan.
Conclusion
We conducted a basic survey for joint implementation and other operations commissioned by the New Energy and Industrial Technology Development Organization (NEDO). The survey is entitled "Rehabilitation of the KESC Gas Turbine Power Plants." As a result, we were able to monitor the status of power supply in Karachi and its surroundings and survey and consider the basics of the rehabilitation plan for the gas turbine power plants covered in our survey. That is, we proposed two cases of rehabilitation plan listed below, and calculated the energy-saving effect and the carbon dioxide reducing effect in each case.
Case 1: Gas turbine and generator are replaced.
Case 2: Gas turbine is replaced. Generator is reused after rewinding its stator coil.
As the basics of the modification plan, we drafted a plan for the thermal power plants, fuel supply equipment, and instrumentation control and arrangement. We also surveyed the schedule of equipment manufacture, transportation and installation and the division of work between the KESC and the Japanese side. We also studied the cost-effectiveness and eco- friendliness of the energy-saving effect and the greenhouse gas reducing effect. Here are the results:
Schedule of equipment manufacture, transportation, and installation: About 9 months (per gas turbine)
Work of the Japanese side: In Case 1, the gas turbines, generators and peripherals
In Case 2, the gas turbines and peripherals
Transportation on a CIF Karachi Port basis, and dispatch of personnel will be limited to instructors on installation and test run.
Initial investment: 84 million US dollars (Case 1), 78 million US dollars (Case 2)
Cost versus energy-saving effect: 107 t/y/million yen (Case 1), 101 t/y/million yen(Case 2)
Cost versus greenhouse gas reducing effect: 330 t- C02/y/million yen (Case 1)
313 t- C02/y/million yen (Case 2)
Profitability calculations revealed that, if the depreciation period was 15 years and special environmental yen credit was applied (with an interest rate of 0.75%), it could be depreciated 7 years after the depreciation period and returned the same rate of initial cost.
Regarding the possibility to spend technologies for energy saving and reducing greenhouse gases, it is confirmed the following:
1) Pakistan has 13 power stations having gas turbines that were put into operation at the same dates as the gas turbine power plants covered in our present survey.
2) Every power station is highly likely to have problems similar to those of the gas turbine power plants covered in our present survey, and we can spread the technologies for energy-saving and reducing greenhouse gases.
Furthermore, we considered the possibility to spread the technologies for energy saving and reducing greenhouse gases regarding the thermal power plants owned by KESC, and observed that they were more effective than the gas turbine power plants.
We felt keenly that the thermal power plants needed a survey and study of the rehabilitation plan as well.
Towards the realization of the project, we will ask KESC and Pakistani Government to consider about the prospect of fund raising by the special environmental yen credit and also continue to deliberate about the possibility of other forms of fund raising. When the possibility of realization of the project has become high, we plan to discuss with the KESC about the details and decide which of the above-mentioned two Cases should be adopted, the implementation schedule in the Case adopted, and share of works to be undertaken by each party
We hope that this survey will lead to actual operations and will be of any help to improving KESC structurally and resolving the problems with electric power in Karachi.
References
Ministry of Economy and Industry, "Guideline for the Calculation of Greenhouse Gas Emissions"
Survey report, "Rehabilitation of the Steam Thermal Power Plants Owned by the KESC"
Guidelines for the Calculation of Greenhouse Gas Emissions
For the purpose of this proposal, greenhouse gas emissions will be calculated by the followingsimplified method of calculation for the effects of the entire project in order to monitor objectivelythe effect of reducing greenhouse gases (such as scale) in the project.
1. Preconditions for calculations(1) All calculations must be based on the effect of energy-saving (or alternative energy
sources) (in terms of crude oil).
(2) Each greenhouse gas other than carbon dioxide must be multiplied by the index specified for the particular type of gas (Reference 3).
(3) If the effect of reducing greenhouse gases is due to any cause other than the effect of energy-saving (or alternative energy source), the calculations for that portion must be with a formula specified by the Intergovernment Panel on Climate Exchange (IPCC).
2. Formula(1) If the effect of reducing greenhouse gases is due only to energy-saving (or alternative
energy source),
Quantity in terms of C02 ( t — C 02/ y )
Effect of energy-saving in terms of crude oil (toe/y)
X 42.62X20X0.99X44/12
1000
Note: For the simplified method of calculation, always use the following values:
a) Effect of energy-saving (or alternative energy sources) (in terms of crude oil in toe/y)
Enter a formula for calculating the effect of energy-saving or alternative sources (energy level reduced (collected or converted) in terms of crude oil.a) In energy collection, specify the form of energy collected and its uses.b) In converting the heat quantity of crude oil, use 10,000kcal/kg.c) In converting the heat quantity of electric power, use 2,646kcal/kWh.d) In steam collection, specify the steam conditions.e) In converting the heat quantity of other energy sources, specify the values used.
b) Convert the value to the energy unit (hat quantity: TJ). b=aX42.62TJ/kt (conversion factor)
c) Covert it to the unit requirement for carbon emissions.
c=bx20tC/TJ (Unit requirement for carbon emissions)d) Correct the incomplete combustion.
d=cx 0.99 (Oxidation ratio factor of carbon)
Evaluation of greenhouse gas reductions Indexes for C02 conversion (global warming indexes)
Greenhouse gas Chemical formula Global warming index
Carbon dioxide COz 1
Methane ch4 21
Nitrous oxide NzO 310(laughing gas)
MFCHFC-23 chf3 11,700HFC-32 ch2f2 650HFC-41 ch3f 150HFC-43-10mee C5H2F10 1,300HFC-125 C2HF5 2,800HFC-134 c2h2f4 1,000
HFC-134a ch2fcf3 1,300HFC-152a c2h4f2 140HFC-143 c2h3f3 300HFC-143a c2h3f3 3,800HFC-227ea c3hf7 2,900HFC-236fa c3h2f6 6,300HFC-245ca c3h3f5 560
RFCPerfluoromethane 0 T1 6,500Perfluoroethane c2f @ 9,200Perfluoropropane p m 7,000Perfluorobutane c4f10 7,000Perfluorocyclobutane 0 p m 8,700Perfluoropentane C5F i2 7,500Perfluorohexane c6f14 7,400
Sulfur hexafluoride SF6 23,900
Greenhouse gas emissions (in terms of C02) = greenhouse gas emissions x global warming index
Survey Report
Rehabilitation for Thermal Power Stations
of KESC
(BIN QASIM and KORANGI TPSs)
1. Possibilities of rehabilitation for the facilities of surveyed plant
The existing thermal power stations owned by KESC are shown in Table 1.1-1.
Table 1.1-1: Thermal Power Station (TPS) of KESC
Stationname
Unit No. Commercialoperation
Designed power generation (MW)
Manufacturer(Boiler/Turbine)
BIN QASIM 1 1983 210 BHK*/Hitachi2 1984 210 BHK*/Hitachi3 1989 210 D-Bub**/Ansaldo4 1990 210 D-Bub**/Ansaldo5 1991 210 BHK*/Hitachi6 1997 210 BHK*/Hitachi
Sub total 1,260KORANGI 1 1966 66 GE
2 1966 66 GE3 1970 125 BHK*/Hitachi4 1977 125 BHK*/Hitachi
Sub total 382Total 1,642
* Babcock-Hitachi ** German Babcock
KORANGI TPS Unit 2 (66MW) has been retired due to turbine shaft breakage.
Based on the results of onsite survey (by interview survey) and the inspection records in the past, the possibilities of rehabilitation for these thermal power stations were considered, especially in terms of turbine components.
According to the result of the interview survey, it has been revealed that KESC is highly concerned with the idea of rehabilitation for their plants aiming at the recovery of generating output by repairing the equipment. And for KORANGI TPS, KESC is interested in re-powering modification with additional installation
of gas turbine equipment.
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2. Outline of onsite power facilities
2.1 Outline of BIN QASIM TPS
BIN QASIM TPS is located in Pipri Area along the Arabian Sea, about 40km east of the center of Karachi. The plant contains 6 units of thermal power facilities. Specifications for each facility are shown in Table 2.1-1.This plant has been operated with constant output (base load operation). With regard to operation time and the number of start and stop for the units, no data has been recorded on site. Therefore, it will be required to calculate such data based on shutdown record (i.e., data of yearly shutdown and stopping time of the units). Based on the data over the past 2 years (1999 and 2000), operation time and the number of start and stop have been found as in Table 2.1-2. Regarding Unit 1,2 and 6, the operation time was reported relatively short allowing for overhaul duration carried out at over the 2 years.
Table 2.1-2: Number of Start and Stop and Operation Time (BIN QASIM TPS)
UnitNo.
Start of Commercial Operation
Number of Start & Stop*1
Operating Hour (Operating Rate)*1
1 Mar. 1984 55 11,903 h (68%)"2
2 Oct. 1984 52 13,803 h (79%)"2
3 Jun. 1990 108 14,494 h (83%)4 May 1991 95 12,861 h (73%)5 Aug. 1991 32 15,094 h (86%)6 Apr. 1998 49 15,844 h (90%)"2
*1: From the record of last two years (1999 & 2000) managed by KESC.
*2: Shutdown hours for overhaul on last two years (1999 &2000) for Unit 1,2 and 6 are 2,785 h / Unit 1,2,640 h / Unit2, and 1,374 h / Units.
Regarding the operating condition, it has been stable with constant output at base load as described earlier. However, the state of the equipment appears considerably deteriorated. Operational facilities with the rated output of 210MW include Unit 6 (at around 200MW) that was recently started in commercial operation, and Unit 1 and 2 (at around 190MW) that had overhaul in recent years. Regarding output power of the other facilities, Unit 3 operates at 90MW, Unit 4 at 140MW and Units at 150MW.
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As for fuel resources, heavy fuel oil (HFO) and light diesel oil (LDO) are utilized for Unit 1 to 4, and for Unit 5 and 6, natural gas in addition to the above-mentioned fuel. However, for the reason that Unit 1 to 4 can be available for gas firing with gas burner pad fitted on and that the production of natural gas has ever increased in Pakistan of recent years, KESC would like to cut down fuel cost by converting the fuel resources of Unit 1 to 4 on heavy fuel to gas firing.
Maintenance work for the power plants carried out at intervals of 7 or 8 years in accordance with the schedule for overhaul, whereas in Japan it takes place at intervals of 2 to 4 years. Therefore it can be assumed that a considerable decrease in generating output and efficiency has been caused due to a prolonged absence of maintenance work. While Unit 3 to 5 in particular, have been continuously in service for a period of about 10 years from start of commercial operation. And almost no inspection seems to have been conducted over those years. All these findings indicate that the deterioration of the facilities can be attributed to a great effect of the seawater used as cooling water, which as a result caused tube-leaks of the boiler, condenser and heaters.
Considering the operating conditions as described above, it is expected that rehabilitation or equipment modification should be conducted for Unit 3 to 5 especially. As far as Unit 1 and 2, there also seems room for improvement, as the boiler, turbine and generator thereof are not operated at the rated output of 210 MW even after overhaul had been carried out and it can be assumed that some degree of equipment deterioration should be developed. As for Unit 6, on the other hand, it has ever maintained the rated output since start of commercial operation. Furthermore, in a regular inspection carried out in 1999 after 8000 hours operation, there was no malfunction in this unit. Therefore it can be thought that no rehabilitation will be required for Unit 6 at this time.Having considered all the viewpoints as mentioned above, rehabilitation should be applied to Unit 1 to 5 at BIN QASIM TPS.
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Table 2.1-1: Specification of Facilities of BIN QASIM TPS
Item/Unit No..1 No. 2 No. 3 No. 4 No. 5 No. 6
Manufacturer
Boiler Babcock-Hitachi Babcock-Hitachi DeutscheBabcock
DeutscheBabcock Babcock-Hitachi Babcock-Hitachi
Turbine Hitachi Hitachi Ansaldo Ansaldo Hitachi Hitachi
Generator Hitachi Hitachi Ercole Marelli Ercole Marelli Hitachi Hitachi
Specification
Boiler
TypeNatural circulation
boilerNatural circulation
boilerNatural circulation
boilerNatural circulation
boilerNatural circulation
boilerNatural circulation
boilerBoiler MCR (t/h) 680 680 680 680 680 680
Main steam press. (MPa.a) 14.56 (147.5 atg) 14.56 (147.5 atg) 14.56 (147.5 atg) 14.56 (147.5 atg) 14.37 (147.5 atg) 14.37 (147.5 atg)
Main steam temp. (°C) 530 530 530 530 530 530
Reheat steam temp. (°C) 530 530 N/A N/A 530 530
Fuel HFO, LDO, or Gas HFO, LDO, or Gas HFO, LDO, or Gas HFO, LDO, or Gas HFO, LDO, or Gas HFO, LDO, or Gas
Turbines
TypeReheat condensing
TCDF-26Reheat condensing
TCDF-26Reheat condensing
TCDF-26Reheat condensing
TCDF-26Reheat condensing
TCDF-26Reheat condensing
TCDF-26
Rated output (MW) 210 210 210 210 210 210
Stages (HP) 8 8 8 8 8 8
(IP) 6 6 6 6 6 6
(LP) 5 stages x 2 flows 5 stages x 2 flows 5 stages x 2 flows 5 stages x 2 flows 5 stages x 2 flows 5 stages x 2 flows
Condenser vacuum (kPa.a) 7.0 7.0 N/A N/A 7.0 7.0
Rotating speed (rpm) 3000 3000 3000 3000 3000 3000
Driving device of BFP Motor Motor Motor Motor Motor Motor
Generator
Type TFLQQ-KD TFLQQ-KD N/A N/A TFLQQ-KD TFLQQ-KDOutput (MVA) 248.30 248.30 247.06 247.06 248.30 248.30
Power factor 0.85 0.85 N/A N/A 0.85 0.85
Start of commercial operation March 1984 October 1984 June 1990 May 1991 August 1991 April 1998
2.2 Outline of KORANGI TPS
KORANGI TPS is located in about 20 km west of the center of Karachi. In the plant are currently 3 units of thermal power facilities in service. Specifications for each facility are shown in Table 2.2-1.
Each facility in this plant has been operated at constant output (base load), as is the case with BIN QASIM TPS. Although operation time and the number of start and stop for the facilities have been found for 1995 to 1999, the total data is not available. Table 2.2-2 below shows the results of the investigation on the data from 1998 and 1999 with start year of commercial operation for each unit. Regarding Unit 4, the operation time is not as long as that of the others. It is because the down time for overhaul during 1999 to 2000 is included.
Table 2.2-2: Number of Start and Stop and Operation Time (KORANGI TPS)
UnitNo.
Start of Commercial Operation
Number of Start & Stop*1
Operating Hour (Operating Rate)*1
1 1961 (N/A) (N/A)2 1962 (Retired) (Retired)3 1970 29 15,725 h (90%)4 1977 23 11,517 h (66%)’2
*1: From the record of last two years (1998 & 1999) managed by KESC.
*2: Shutdown hours for overhaul on last two years (1999 &2000) for Unit 4 is 4,965 h.
Regarding the operating conditions, although the operating output has been constant, the deterioration of the facilities has visibly developed because it is over 20 years since the start of commercial operation. Maximum output for each unit is; approx. 25 MW for Unit 1, and 90 MW for Unit 3 and 4. The fuel
for each unit is HFO and natural gas.
Maintenance work for the facilities has been conducted at the intervals of 7 to 8 years in accordance with the schedule for overhaul. However, a considerable decrease in generating output and efficiency is remarkable due to a prolonged absence of maintenance work. So the deterioration of the facilities can be, as in the case with BIN QASIM, attributed to a great effect of the seawater used as cooling water, which as a result caused tube-leaks of the boiler, condenser and
heaters.
Considering the operating conditions as described in the above, it is expected that rehabilitation or equipment modification should be conducted for Unit 3 to 4 especially. As for Unit 1, it has been in service over 40 years and it can be assumed that the effect of rehabilitation on the unit may not be sufficient because Unit 1 has only 66MW of capacity. Therefore, Unit 1 does not appear applicable for rehabilitation.
Having considered all the viewpoints as mentioned above, rehabilitation should be applied to Unit 3 to 4 at KORANGI TPS.
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Table 2.2-1: Specification of Facilities of KORANGI TPS
Item/Unit No. 1 No. 2 No. 3 No. 4
Manufacturer Boiler Not surveyed Not surveyed Babcock-Hitachi Babcock-Hitachi
Turbine GE GE Hitachi Hitachi
Generator GE GE Hitachi Hitachi
SpecificationBoiler Type N/A N/A Natural circulation boiler Natural circulation boiler
Boiler MCR (t/h) N/A N/A 400 400Main steam press. (MPa.a) N/A N/A 132 132Main steam temp. (°C) N/A N/A 540 540Reheated steam temp. (°C) N/A N/A 540 540Fuel N/A N/A HFO HFO
Turbine Type N/A N/A Reheat condensing TCDF-23
Reheat condensing TCDF-23
Rated output (MW) 66 66 125 125Stages (HP) N/A N/A 10 10
(IP) N/A N/A 12 12
(LP) N/A N/A 5 stages x 2 flows 5 stages x 2 flowsCondenser Vacuum (kPa.a) N/A N/A 8.5 8.5Rating speed (rpm) 3000 3000 3000 3000Driving device of BFP Motor Motor Motor Motor
Generator Type N/A N/A TFLH-K TFLH-KOutput (MVA) N/A N/A 160 160Rated power factor N/A N/A 0.85 0.85
Start of commercial operation 1961 1962 1970 1977
3. Conditions of onsite power facilities
3.1 Facilities of BIN QASIM TPS
(1) Boiler
Deterioration of boiler equipment has been found from operation data, especially significant deterioration has been found in the boiler of Unit 3 to 5 due to an absence of overhaul over the past years.
Unit 3 to 5 keep constant operation at between 50 % and 75% of the rated output (210 MW), which comes to 90 MW to 150 MW. Further, steam pressure and temperature have been below the rated value and can be therefore causal factors of the decrease in turbine efficiency. In respect to Unit 3, it has been reported that as seawater leaked out of the condenser during commissioning and was for a long period of time in service as it is, salt content precipitated at the boiler water tube with considerable frequency and as a result steam blow occurred.
As far as Unit 1 and 2, they were overhauled about one year ago to replace the boiler tube with new one. They have been recovering in terms of steam flow, pressure and temperature up to those of the rated value. The effect of rehabilitation held during overhaul is obviously confirmed. In terms of the generating output of Unit 1 and 2, it has recovered from about 100 MW up to 195 MW at maximum. Regarding auxiliary equipment for the boiler, in spite that KESC itself carries out a regular inspection, it has been found that unit trip occurred frequently in the fuel pump and PDF (Forced Draught Funs), because of their low reliability.
(2) Turbine
According to operation data, generating output of Unit 1 and 2, in spite of the fact that steam flow and condition of the boiler have been recovering up to the rated value, has not yet reached the rated output (at 195 MW of 210 MW rated). This can be attributed to the deterioration in the efficiency of turbine
and auxiliaries.
Regarding Unit 3 and 4, there is no detailed design data available, so that the deterioration of the equipment cannot be identified clearly. According to data by KESC, however, it has been found that the turbine plant efficiency is
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about 30 % and the lowest of all the 6 units.As for Unit 5, there is no considerable deterioration in the efficiency compared to that of Unit 3 and 4, which are constructed at the same time as that of Unit 5. Nevertheless, it can be expected that the deterioration has developed due to continuous operation over 10 years since start of commercial operation.
(3) Turbine Auxiliaries (D Condenser
Except for Unit 2, the condenser vacuum was almost equivalent to the rated value. It can be because this survey was carried out in the winter season. However, the rated vacuum for Unit 3 and 4 are not available, but still keeps lower values than those of Unit 5. Further, it has been reported by KESC that a tube-leak occurred in the condenser of Unit 5. In respect to Unit 3 and 4, out-of-service operation of chlorine plant at seawater intake and consequently a seawater leak of condenser occurred, which has an adverse effect on the boiler. Although there is a polisher installed to protect the boiler from a seawater leak, it has not been in service due to lack of maintenance work.
(2) LP, HP Heaters and DeaeratorAt this survey, there is no detail operation data of LP and HP heaters and dearerator, therefore the functionality of the heaters efficiency was not verified. The results of the interview survey indicate that concerning Unit 1 and 2 for the heaters and deaerator, there is no major problem, and that as to Unit 3 to 5, a tube leak has occurred in both LP and HP heaters. It has been also reported that there is a noticeable tube leak especially in LP No.2 heater of Unit 4 and therefore it has been out of service.
® Pumps (BFP, CWP, etc)With regard to the pumps, although entire replacement of each unit had been carried out by KESC, there was a question from KESC arising as to whether there would be more room for improvement for the components of the pump. At the present moment, there is no particular problem that might cause plant shut down. However, it has been found that there are some vibration problems and damage to the components.
(4) GeneratorAccording to the results of the interview survey, it has been found that there
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is no major problem that may affect the current operation system. Furthermore, inspection and repair have been carried out at every overhaul under the direction of supervisors from suppliers.
(5) OtherRegarding the control equipment and supervisory instruments, it has been found that many supervisory instruments in the control room and field instruments are not in service due to their malfunction. In addition, it has been also confirmed that CRT in the control room is out of order.
3.2 Facilities of KORANGI TPS
(1) Boiler
The operation data indicate that there is deterioration in the boiler facility. It has also been reported by KESC that a tube leak often occurs in the boiler.
Steam flow for both Unit 3 and 4 are indicated as the constant operation at 70 % of the rated value, and the output is below the rated output. In terms of steam pressure, it is far below the rated value for both Unit 3 and 4.
(2) Turbine
It was impossible to calculate the turbine efficiency from data recorded by KESC due to lack of parameter. However, considering the past operation for 23 years of Unit 4 and 30 years of Unit 3, it can be assumed that there is considerable deterioration in the turbine efficiency. Further, from the results of overhaul held between 1999 and 2000, rust development was visibly confirmed on both the high and intermediate pressure rotor and the low-pressure rotor. It has also been confirmed that there is significant deterioration and damage such as erosion of the shroud cover and fractures on the erosion shield for the last stage buckets. As for the other parts of the turbine, it has been reported that the lower-half diaphragm is firmly fixed on the casing, which consequently led to difficulties in performing disassembly, and that there is considerable deterioration in and damage to each
component.
(3) Turbine Auxiliaries
Q Condenser
10 -
The degree of vacuum for the condenser was almost equivalent to the rated value. It can be because this survey was carried out in the winter season. It has been reported by KESC that a tube-leak occurred frequently in the condenser of Unit 3, and just before this survey, there has been tube-leak occurred in the condenser of Unit 4.
© LP, HP Heaters, Deaerator and H2 Cooler
At this survey, there is no detailed operation data of heater; therefore the functionality of the heater efficiency was not verified. The results of the interview survey indicate that replacement of HP-No.5, 6 and LP- No. 2,3 heater for Unit 3 has been carried out. And KESC is now planning the replacement of LP-No.1 heater and the deaerator for Unit 3. Concerning Unit 4, it has been reported that a tube leak in the heater is visibly developed, and that HP-No.5, 6 heater and LP-No.3 heater have been out of service. Furthermore, in respect to H2 cooler, a visible tube leak has been found. This can be one of the causal factors of the plant shut down.
© Pumps (BFP, CWP, etc)
With regard to the pumps, although entire replacement of each unit had been carried out by KESC, there was a question from KESC arising as to whether there would be more room for improvement for the components of the pump. At the present moment, there is no particular problem that might cause plant shut down. However, it has been found that there are some vibration problems and damage to the components.
(4) Generator
According to the results of the interview survey, inspection and repair have been carried out at every overhaul under the direction of supervisors from suppliers. Further, it has been reported that there is a cooling hydrogen leak in Unit 3. In respect to Unit 4, it has been confirmed in the previous overhaul that there was electric erosion on the generator rotor wedge and it
was not repaired at last overhaul.
(5) Other
It has been reported in the interview survey that the many supervisory instruments in the control room is not in service due to its malfunction. It should be, therefore, required to identify the details in future investigation.
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4. Prerequisite for progress of facilities of Surveyed Unit
4.1 Prerequisite for improvement of facilities at BIN QASIM TPS
(1) Boiler
According to the results (operation data) of the previous overhaul for Unit 1 and 2, it appears possible to restore steam conditions for the boiler to the rated value by replacing the boiler tube. The degree of efficiency recovery value thereby, however, remains to be investigated at before and after overhaul. Considering the conditions of Unit 3 to 5, it should be necessary to consider modification and repair of the boiler equipment in order to prevent deterioration. It is because the deterioration of the boiler appears considerably developed due to decade long net operation. It should be also required to plan and study on the evaluation and improvement of boiler
efficiency.
Fuel used for Unit 1 to 4 is oil firing, and for Unit 5 and 6 is natural gas and oil mixed firing. In Pakistan of recent years, the production of natural gas has ever increased. It should be therefore required to consider the cut down of fuel cost by modifying the boilers to apply to gas firing which consequently leads to low-pollution.
Further, the boiler auxiliaries has frequently tripped and resulted in a causal factor of plant shut down. Thus, it should be necessary to plan for replacement with reliable equipment in order to improve the reliability of the
plant.
(2) Turbine
Unit 1 and 2 have been operated over 15 years since start of commercial operation, and considerable deterioration is of concern in the turbine equipment and especially in the high-temperature components. Therefore, a detailed inspection and remaining life assessment for the major equipment in the future overhaul should be carried out, and then proposals for modification and repair for the components causing the deterioration of
efficiency should be planned.
Regarding Unit 3 and 4, as no detailed design has been available, performance evaluation and reverse engineering of each component of the
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turbine should be required in order to carry out rehabilitation including the efficiency improvement. Thus, onsite investigation (e.g., sketching and measurement, etc.) should be carried out in the future overhaul, and then proposals for modification and repair should be planned.
As for Unit 5, the degree of deterioration and damage in the turbine components will be assumed from the results of a detailed inspection and remaining life assessment for Unit 1 and 2 being held in the future. In addition, a detailed inspection should be carried out at overhaul to identify the conditions of deterioration, and then proposals for modification and repair should be planned.
(3) Turbine Auxiliaries
Regarding part of the turbine auxiliaries (i.e., condenser, heaters, pumps, etc), KESC carried out itself replacement and modification. Therefore, data on the past inspections, repair and replacement should be collected and analyzed. Furthermore, a detailed inspection and performance evaluation should be carried out to plan the proposals for repair and modification.
(4) Generator
With regard to the plan for replacement of the generator components, a detailed inspection should be carried out in order to identify the degree of deterioration in each component. Then proposals for modification and repair should be planned considering the results of an inspection and performance evaluation.
Further, as for Unit 3 and 4, it will be required to carry out onsite investigation (e.g., sketching and measurement, etc.) in the future overhaul.
The results of survey and the rehabilitation strategies for the equipment are shown in Table 4.1-1 to 4.1-3.
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Table 4.1-1 Result of Survey and Rehabilitation Plan for BIN QASIM TPS (1)
No. Item Unit No. 1 Unit No. 2 Unit No. 3 Unit No. 4 Unit No. 5
1 Operation
(1) Operating output 195 MW 195 MW 90 MW 140 MW 150 MW
(2) Operating condition Base load operation Base load operation Base load operation Base load operation Base load operation
(3) Fuel Oil (HFO, LDO) Oil (HFO, LDO) Oil (HFO, LDO) Oil (HFO, LDO) Oil (HFO, LDO) & Natural gas
2 Maintenance Overhaul carried out at
intervals of 7 to 8 years
Boiler, turbine, generator and
auxiliaries were overhauled at
1999-2000.
Overhaul carried out at
intervals of 7 to 8 years
Boiler, turbine, generator and
auxiliaries were overhauled at
1999-2000.
Time of overhaul carried out
is not clear.
(Overhaul is planned at
interval of 7 to 8 years)
Time of overhaul carried out
is not clear.
(Overhaul is planned at
interval of 7 to 8 years)
Overhaul carried out at
intervals of 7 to 8 years
(Overhaul is under planning
in 2001)
3 Boiler
(1) Operating condition
(from operation
records)
Steam flow rate: 645 t/h
(MCR 680 t/h)
Main steam press.: 14.0 MPa.a
(Rated: 14.56 MPa.a)
Main steam temp.: 525°C
(Rated: 530°C)
Reheat steam temp.: 520°C
(Rated: 530°C)
Steam flow rate: 690 t/h
(MCR 680 t/h)
Main steam press.: 14.0 MPa.a
(Rated: 14.56 MPa.a)
Main steam temp.: 520°C
(Rated: 530°C)
Reheat steam temp.: 520°C
(Rated: 530°C)
Steam flow rate: 285 t/h
(MCR N/A)
Main steam press.: 9.0 MPa.a
(Rated: 14.56 MPa.a)
Main steam temp.: 510°C
(Rated: 530°C)
Reheat steam temp.: 505°C
(Rated: N/A)
Steam flow rate: 285 t/h
(MCR N/A)
Main steam press.: 9.0 MPa.a
(Rated: 14.56 MPa.a)
Main steam temp.: 510°C
(Rated: 530°C)
Reheat steam temp.: 505°C
(Rated: N/A)
Steam flow rate: 475 t/h
(MCR 680 t/h)
Main steam press.: 14.0 MPa.a
(Rated: 14.37 MPa.a)
Main steam temp.: 526°C
(Rated: 530°C)
Reheat steam temp.: 525°C
(Rated: 530°C)
(2) State of demand
equipment and
parts, and
proposing
countermeasure
Boiler tubes have been
replaced at previous overhaul.
Regarding as boiler auxiliaries,
inspection and repair are
necessary because of their low
reliability.
Boiler tubes have been
replaced at previous overhaul.
Regarding as boiler
auxiliaries, inspection and
repair are necessary because
of their low reliability.
Replacement of boiler tube is
necessary as decrease of
main steam flow and
pressure.
Regarding as boiler
auxiliaries, inspection and
are necessary because of
their low reliability.
(ex. Trip of forced draught
funs).
Replacement of boiler tube is
necessary as decrease of
main steam flow and
pressure.
Regarding as boiler
auxiliaries, inspection and
are necessary because of
their low reliability.
(ex. Trip of forced draught
funs).
Damage of boiler tubes is
expected from decrease of
main steam flow.
Inspection of boiler tube is
necessary..
Table 4.1-2 Result of Survey and Rehabilitation Plan for BIN QASIM TPS (2)No. Item Unit No. 1 Unit No. 2 Unit No. 3 Unit No. 4 Unit No. 5
4 Turbine
(1) Operating conditions Output: MAx.195 MW Output: MAx.195 MW Output: MAx.195 MW Output: MAx.195 MW Output: MAx.195 MW
(from operation record) (Rated 210 MW) (Rated 210 MW) (Rated 210 MW) (Rated 210 MW) (Rated 210 MW)
Condenser vacuum: Condenser vacuum: Condenser vacuum: Condenser vacuum: Condenser vacuum:
Max.S.OkPa.a (Rated: 7.0kPa.a) Max.S.OkPa.a (Rated: 7.0kPa.a) Max.S.OkPa.a (Rated: 7.0kPa.a) Max.S.OkPa.a (Rated: Y.OkPa.a) Max.S.OkPa.a (Rated: 7.0kPa.a)
(2) State of damaged (1) Deterioration of turbine (1) Deterioration of turbine (1) It is expected that (1) It is expected that (1) Deterioration of turbine
equipment and efficiency (erosion of nozzle efficiency (erosion of nozzle deterioration of turbine deterioration of turbine efficiency (erosion of nozzle
parts, and proposing and moving blades and and moving blades and efficiency and parts be efficiency and parts be and moving blades and
countermeasure. increase of packing gap) is increase of packing gap) is developed. developed. increase of packing gap) is
expected from comparison expected from comparison From the data recorded by From the data recorded by expected.
between main steam between main steam KESC it is confirmed the KESC it is confirmed the Although the turbine
condition, condenser condition, condenser deterioration of turbine deterioration of turbine deterioration is assumed to
vacuum and generating vacuum and generating efficiency. efficiency. be small because of shorter
output output operating time than Unit 1
(2) It is expected that (2) It is expected that and 2, detail inspection
(2) It is expected that turbine (2) It is expected that turbine deterioration of turbine parts deterioration of turbine parts should be carried out at
parts (especially high parts (especially high is developed from number of is developed from number of overhaul.
temperature parts) are temperature parts) are unscheduled shutdown. unscheduled shutdown.
deteriorated by operation for deteriorated by operation (2) Development of turbine
over 15 years. for over 15 years. (3) Although detail design of (3) Although detail design of deterioration is expected
Detailed inspection and Detailed inspection and turbine is not available, it is turbine is not available, it is from the damage condition
remaining life assessment remaining life assessment possible to modify the possible to modify the turbine of Unit 1 and 2, it is
are should be carried out at are should be carried out at turbine after the detail after the detail measurement necessary to plan to replace
overhaul and plan to overhaul and plan to measurement of turbine at of turbine at overhaul. the turbine parts and
replacement and replacement and overhaul. preparation of spare parts
modification for the modification for the based on the inspection
deteriorated parts. deteriorated parts. result.
Table 4.1-3 Result of Survey and Rehabilitation Plan for BIN QASIM TPS (3)No. Item Unit No 1 Unit No. 2 Unit No. 3 Unit No. 4 Unit No. 5
5 Turbine auxiliaries
(1) Condenser Condenser vacuum is
indicated near the rated value
at this survey (winter season).
Investigation on summer
season is necessary.
Condenser vacuum is
indicated below the rated
value, it is assumed tube leak
and lack of circling water.
It is necessary the investigation
of decrease of condenser
vacuum.
The rated condenser vacuum
is not available.
The survey of inspection
record and operation data is
necessary.
The rated condenser vacuum is
not available.
The survey of inspection record
and operation data is necessary.
Condenser vacuum is indicated
near the rated value at this
survey (winter season).
KESC reported that condenser
tube leak has occurred.
Investigation on summer season
is necessary.
(2) LP, HP heater,
Deaerator
Efficiency evaluation is not
possible from reported data
from KESC.
Investigation of deteriorated
parts and performance is
necessary.
Efficiency evaluation is not
possible from reported data
from KESC.
Investigation of deteriorated
parts and performance is
necessary.
Efficiency evaluation is not
possible from reported data
from KESC.
KESC reported that there are
heater tube leaks occurred
on LP and HP heaters.
Investigation of deteriorated
parts and performance is
necessary.
Efficiency evaluation is not
possible from reported data
from KESC.
KESC reported that there are
heater tube leaks occurred on
LP and HP heaters and LP No.
2 heater is now out of service.
Investigation of deteriorated
parts and performance is
necessary.
Efficiency evaluation is not
possible from reported data
from KESC.
KESC reported that there are
heater tube leaks occurred on
LP and HP heaters.
Investigation of deteriorated
parts and performance is
necessary.
(3) Pumps
(BFP, CWP, etc.)
Replacement of pumps and
their parts are carried out by
KESC.
Detail inspection and plan to
replacement and modification
are necessary.
Replacement of pumps and
their parts are carried out by
KESC.
Detail inspection and plan to
replacement and modification
are necessary.
Replacement of pumps and
their parts are carried out by
KESC.
Detail inspection and plan to
replacement and modification
are necessary.
Replacement of pumps and
their parts are carried out by
KESC.
Detail inspection and plan to
replacement and modification are
necessary.
Replacement of pumps and
their parts are carried out by
KESC.
Detail inspection and plan to
replacement and modification
are necessary.
6 Generator Although overhaul was carried
out by direction of supplier's
supervisor, deterioration of
generator parts are expected
from operation of over 15
years.
It is necessary to make the
replacement and modification
plan.
Although overhaul was carried
out by direction of supplier's
supervisor, deterioration of
generator parts are expected
from operation of over 15
years.
It is necessary to make the
replacement and modification
plan.
However, Maintenance
condition is almost same as
Unit 1 and 2, detail design is
not available.
Therefore, planning of
replacement and modification
of generator parts are
necessary after on-site
investigation and confirmation
of deterioration at overhaul.
However, Maintenance
condition is almost same as Unit
1 and 2, detail design is not
available.
Therefore, planning of
replacement and modification of
generator parts are necessary
after on-site investigation and
confirmation of deterioration at
overhaul.
After confirmation of
deterioration state of Unit 1 and
2 generator parts, planning of
repair and preparation of spare
parts are necessary for the parts
that expected to deteriorate.
4.2 Prerequisite for improvement of the facilities at KORANGI TPS
(1) Boiler
Deterioration in the boiler components is remarkable due to seawater leaks in the condenser and a long-term operation. Therefore, it is necessary to plan the proposals for replacement and modification for the entire boiler equipment.
(2) Turbine
As confirmed in the boiler, deterioration in the turbine components is remarkable due to a prolonged operation. Unit 3 and 4 have also been in service over 20 years and have overrun the estimated average lifetime of turbine parts. Therefore, it should be unconditionally required to plan the proposals for comprehensive modification and repair without a detailed inspection and remaining life assessment.
(3) Turbine Auxiliaries
Regarding part of the turbine auxiliaries (i.e., condenser, heaters, pumps, etc), KESC carried out itself replacement and modification. Therefore, data on the past inspections, repair and replacement should be collected and analyzed. Furthermore, a detailed inspection and performance evaluation should be carried out to plan the proposals for repair and modification.
(4) Generator
It should be required to plan the proposals for comprehensive replacement of the entire components after considering the deterioration of the generator equipment due to constant operation over the long period.
The results of survey and the rehabilitation strategies for the equipment are shown in
Table 4.2-1 to 4.2-3.
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Table 4.2-1 Result of Survey and Rehabilitation Plan for KORANGI TPS (1)
No. Item Unit No. 3 Unit No. 4
1 Operation(1) Generating output 90 MW 90 MW(2) Operating condition Base load operation Base load operation(3) Fuel Oil (HFO, LDO) and Natural gas Oil (HFO, LDO) and Natural gas
2 Maintenance Overhaul carried out at intervals of 7 or 8 years.Turbine and Generator wereoverhauled at 1997.
Overhaul carried out at intervals of 7 or 8 years.Turbine and Generator wereoverhauled at 1999 to 2000.
3 Boiler(1) Operating condition (From operation records)
Steam flow rate: Max.268t/h (MCR 400t/h)Main steam press.: 9.75MPa.a (Rated: 12.4 MPa.a)Main steam temp.: 527°C (Rated: 538°C)Reheated stem temp.: 535°C (Rated: 538°C)
Steam flow rate: Max.268t/h (MCR400t/h)Main steam press.: 10.3MPa.a (Rated: 12.4 MPa.a)Main steam temp.: 528°C (Rated: 538°C)Reheated stem temp.: 546°C (Rated: 538°C)
(2) State of damaged equipment and parts, and proposing countermeasure
Deterioration of boiler isconfirmed from decrease ofmain steam flow andpressure.Occurrence of boiler tube leak is reported from KESC and the detail inspection and planning to replace deteriorated parts are necessary.
Deterioration of boiler isconfirmed from decrease ofmain steam flow andpressure.Occurrence of boiler tube leak is reported from KESC and the detail inspection and planning to replace deteriorated parts are necessary.
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Table 4.2-2 Result of Survey and Rehabilitation Plan for KORANGI TPS (2)
No. Item Unit No. 3 Unit No. 4
4 Turbine
(1) Operating condition Output: Max.90 MW Output: Max.90 MW(from Operation records) (Rated: 125 MW) (Rated: 125 MW)
Condenser Vacuum: Condenser Vacuum:Max.6.5kPa.a Max.8.2kPa.a(Rated 8.5kPa.a) (Rated 8.5kPa.a)
(2) State of damaged (1) Operation time is over 20 (1) On the last overhaul, itequipment and parts, years and maintenance was confirmed that theand proposing condition is almost same as deterioration of HIP andcountermeasure Unit 4, it is expected that LP rotors is heavy and
turbine parts deteriorated replacement of theseand damaged as heavily as rotors is necessary.that of Unit 4.
(2) On the last overhaul, it(2) The modification plan of was confirmed that all LP
same as Unit 4 mentioned lower diaphragms areas right is necessary. fixed on the casing and it
is impossible to disassemble.And from heavily damages of diaphragms, replacement of these diaphragms is necessary.
(3) From the result ofinspection carried out at last overhaul, the deterioration of turbine efficiency are expected, so the modification of turbine including efficiency improvement with new technology is necessary.
19
Table 4.2-3 Result of Survey and Rehabilitation Plan for KORANGI TPS (3)
No. Item Unit No. 3 Unit No. 4
5 Turbine auxiliaries
(1) Condenser Condenser tube leak is confirmed remarkably.For stable operation and effect to other equipment, planning to replace the parts is necessary.
It is reported that condenser tube leak has occurred fromKESC.It is expected that efficiency deterioration and effect on the boiler and heaters, planning of replacement of the parts is necessary based on the detail inspection.
(2) LP, HP heater, Deaerator
LP No. 2, 3 and HP No. 5 and6 heaters had been replaced, and LP No. 1 heater and deaerator is necessary to be replaced with new one for deterioration.And hydrogen cooler tube leak is frequently occurred because it is on the condensate water system.
LP No. 3, HP No. 5 and 6 heaters are now out of service because of their heavy tube leak.Other heaters are expected the same deterioration, planning of replacement of these heaters is necessary.
(3) Pumps(BFP, CWP, etc.)
However maintenance and replacement of equipment and its parts are carried out by KESC, development of deterioration is remarkable.It is necessary to plan the replacement of parts and preparation of spear parts.
However maintenance and replacement of equipment and its parts are carried out by KESC, development of deterioration is remarkable.It is necessary to plan the replacement of parts and preparation of spear parts.
6 Generator Deterioration and damage of generator parts are expected for 30 years of long-term operation.It is necessary to plan the replacement of total parts of generator.
Deterioration and damage of parts are remarkable for over 20 year operation.However the damage of rotor wedge was confirmed at last overhaul, repair works were not carried out.The deterioration and damage are expected to develop by future operation, planning of the replacement of total parts of generator is necessary.
20
5. Effect of Rehabilitation for Thermal Power Stations
5.1 Effect of rehabilitation for BIN QASIM TPS
Regarding the effect of rehabilitation for the equipment of the BIN QASIM TPS, followings can be expected.
(1) Plant Life Extension
KESC is now expecting that the plant should be kept in service for a period of 30 years from the start of commercial operation to an average plant lifetime. However, by implementing rehabilitation, it can be expected that the conditions of the equipment will considerably improve and that the lifetime will extend up to 20 to 30 years. Further, it should be quite possible to extend lifetime by means of regular inspection and repair.
(2) Recovery of Generating Output
It is expected that the decrease in power output due to deterioration and damage should be recovered by means of the implementation of rehabilitation. Operation at the rated output will be possible by implementing comprehensive rehabilitation for the plant facilities. Maximum capability of BIN QASIM TPS is approximately 970 MW with a total of 6 units. It can be anticipated that the generating output will be recovered for approximately 280 MW to reach the total rated output of approximately 1250 MW even if a decreased amount of output for Unit 6 is excluded. Further, the units can retain the recovered output after the rehabilitation by means of regular inspection and repair.
(3) Recovery and Improvement of Plant Efficiency
Although it has been confirmed that the generating efficiency has been considerably decreased due to deterioration in the equipment, it is possible to recover the efficiency up to almost the designed value. What is more, further recovery can be expected by replacing with components developed by new technology.
(4) Recovery of Reliability
Of all the units, shut down for failure in the equipment occurs frequently in Unit 1 to 4, which affects the stable supply of electric power. By implementing the
21
rehabilitation, the reliability for the plant facilities and stable supply of electric power can be recovered.
5.2 Schedules for Investigation and Rehabilitation (for BIN QASIM TPS)
In order to make the schedule of the rehabilitation, any facilities with longer operating time and a large number of start and stop should be selected, and then the investigation be carried out. The contents of the schedule are as follows;
(1) Investigation at overhaul and study (approx. 6 months)
(2) Performance evaluation for the facilities and study (approx.6 months)
In addition, in order to plan the proposals for the rehabilitation, a detailed inspection and remaining life assessment for any facilities with longer operating time and a large number of start and stop should be initially conducted. Then the rehabilitation schedule and plan for all the facilities subject to rehabilitation should be respectively developed.
5.3 Effect of rehabilitation for KORANGI TPS
The effect of the rehabilitation for the equipment of KORANGI TPS can be expected as follows;
(1) Plant Life Extension
Considering the 30 year-operating duration for Unit 3 and 23 years for Unit 4 and maintenance condition, it can be assumed that the remaining life of facilities for both units is coming near to the end. Therefore, by implementing rehabilitation, it can be expected that the lifetime will drastically extend.
(2) Recovery of Generating Output
The current total output for Unit 3 and 4 is approximately 180 MW at maximum. However, it can be anticipated that the output will be recovered approximately 70 MW to reach the total rated output of approximately 250 MW (for Unit 3 and 4) by implementing the rehabilitation. Further, the units can retain the recovered output after the rehabilitation by means of regular inspection and repair.
In addition, KESC has the interest in re-powering modification with additional installation of gas turbine. Therefore, the study for this modification should be
conducted.
(3) Recovery and Improvement of Plant Efficiency
Although it has been confirmed that the generating efficiency has been considerably decreased due to deterioration in the equipment, it is possible to recover the efficiency up to almost the designed value. What is more, further recovery can be expected by replacing with components developed by new technology.
(4) Recovery of Reliability
Shut down for failure in the equipment occurs in both Unit 3 and 4, which affects the stable supply of electric power. By implementing the rehabilitation, the reliability for plant facilities and stable supply of electric power can be recovered.
5.4 Schedules for Investigation and Rehabilitation (for KORANGI TPS)
In order to make the schedule of the rehabilitation, any facilities with longer operating time and a large number of start and stop should be selected, and then the investigation be carried out. The contents of the schedule are as follows;
(1) Performance evaluation for the facilities and study (approx.6 months)
In addition, in order to plan the proposals for the rehabilitation, a rehabilitation schedule and plan for all the facilities subject to rehabilitation should be respectively developed as both Unit 3 and 4 without detailed inspection and remaining life assessment.
23
6. Conclusion
Results of the survey on the facilities at the thermal power plants of KESC are indicated as below;
(1) Generating Output
As a result of the survey on the operational status of the facilities, it has been found that most of the facilities are lack of output and that it is impossible to operate at the rated output due to considerable deterioration attributed to a long-term operation of the facilities.
(2) Generating Efficiency
It is revealed that plant efficiency has been deteriorated, causing the increase of fuel and the deterioration in power output.
(3) Operational Reliability
As the plant equipment has a high incidence of defect and failure, which consequently causes the frequent occurrence of unscheduled shutdown, it is difficult to maintain stable electric power supplies.Furthermore, after having considered the actual operating conditions of the plants and the designing specifications, the units and scope for rehabilitation of the abovementioned plant at KESC are shown as follows;
(4) Units for the Rehabilitation
It has been determined to conduct rehabilitation for Unit 1 to 5 of BIN QASIM TPS and Unit 3 and 4 of KORANGI TPS considering the current conditions of deterioration and maintenance efficiency of the facilities.
(5) Scope of the Rehabilitation
As mentioned many a time, it is revealed that the deterioration of the plant facilities has been considerably developed. Thus, the recovery of output, efficiency and reliability as well as the life extension of the equipment should be primarily considered and therefore, it is essential to carry out for the entire equipment including the boiler, turbine, generator, and auxiliary equipment (i.e., condenser, heaters, pumps, etc.).
24
(6) Contents of the Rehabilitation
Contents of the rehabilitation include an onsite investigation of the equipment, and preparing proposals for modification and replacement of any deteriorated components. In addition, it should be concurrently required to plan the replacement by new components with new technologies in order to efficiency improvement.
(7) Effect of Rehabilitation
As the effect of the rehabilitation, the recovery of generating output and efficiency up to the rated value, life extension of the facilities, and the recovery of reliability for stable electric power supplies, etc. can be expected. Furthermore, although it was not within the scope of this survey, it can be possible to improve the operational reliability and efficiency by modifying the control equipment.
It can be highly expected that further investigation should be carried out to find the operational conditions and the degree of deterioration of the equipment, and the past maintenance records that will be necessary for future rehabilitation.
25
List of technical surveyors
Surveyor Responsibility Items surveyed
OsamuOkada Project manager
Overall supervision of the project.Generally managing basic items of the project.
MakotoNishimura Project sub-manager
Overall supervision assistance of the project. Generally managing basic items of the project.
ShigeoMu rata
Thermal system coordinator
Considers and evaluates the project schedule, particularly the plant efficiency after replacement.
FumiyukiHi rose
Gas turbine maintenance engineer
Considers the project schedule in terms of its gas turbine equipment. Generally managing gas turbine equipment.
YoshikazuMoritomo
Gas turbine maintenance engineer
Considers the project schedule in terms of its gas turbine equipment. Considers in detail the gas turbine equipment.
SatoshiKusaka
Instrumentation and control engineer
Considers the project plan in terms of its instrumentation and control design. Generally managing the control design.
FumiharuMoriwaki
Instrumentation and control engineer
Considers the project plan in terms of its instrumentation and control design.
MitsuhiroNunokawa Electric system engineer
Considers the project plan in terms of its electric system design.
TomoyoshiEndo Generator engineer
Considers the project schedule in terms of its generator design.
Ken-ichiTsukano Site layout engineer
Considers the project schedule in terms of its overall layout plan. Considers a carry-in plan for the gas turbine.
MasanoriFujisaki Control panel engineer
Considers the project schedule in terms of its control panel design.
Any part or a whole of the report shall not be disclosed without prior content of International Cooperation Center, NEDO.
Phone 03 (3987) 9466 Fax 03 (3987) 5103
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