national thermal power cooperation

7/31/2019 National Thermal Power Cooperation

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NATIONAL THERMAL POWER COOPERATION

BADARPUR THERMAL POWER STATION

NEW DELHI

Submitted by:

Nisar Ansari

B.Tech 3rd Year

09ECS-54

Electronics and communication Engineering

JAMIA MILLIA ISLAMIA ,NEW DELHI-110025

Duration- 21/05/2012 to 30/06/2012


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ACKNOWLEDGEMENT

I would like to express a deep sense of gratitude and thanks to Mr AJEET KUMAR OJHA-

DGM(HR)without the wise counsel and able guidance, it would have been impossible to complete the

report

in this manner.

The help rendered by Mrs RACHANA SINGH BHAL, Sr. Manager, National Thermal

PowerCorporation for experimentation is greatly acknowledged.

I would also like to express gratitude to the HOD and other faculty members of department

of

Electronics and communication engineering, MNNIT for their intellectual supportthroughout the

course of this work.

Finally, I would like to thanks Er. SONIA SINGH and all other technical staff of B.T.P.S.for giving

helping me throughout the training period.

Nisar Ansari


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ECE-MNNIT ALLAHABD

[email protected]


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CONTENT

1. INTRODUCTION TO THE COMPANY

2. OPERATION OF POWER PLANT

3. VARIOUS CYCLE AT POWER STATION

4. CONTROL & INSTRUMENTATION

5. IT DEPARTMENT

6. REFERENCE


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. About The Company

. Vision

. Strategies

. Environmental Policy

. Evolution


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About The Company

NTPC, the largest power Company in India, was setup in 1975 to accelerate powerdevelopment in

the country. It is among the worlds largest and most efficient power generation companies.

InForbes list of Worlds 2000 Largest Companies for the year 2007, NTPC occupies 411th

place.

A View Of Badarpur Thermal Power Station, New-Delhi

NTPC has installed capacity of 29,394 MW. It has 15 coal based power stations (23,395

MW), 7 gasbased power stations (3,955 MW) and 4 power stations in Joint Ventures (1,794 MW). The

company has power generating facilities in all major regions of the country. It plans to be a

75,000

MW company by 2017.

Types Of Power Station

Number

Capacity(MW)

Coal Based Power Station

15

23,395

Gas Based Power Station

7

3,955


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Joint Venture

4

1,794

Total Capacity 29,394 MW

NTPC has gone beyond the thermal power generation. It has diversified into hydro power,

coalmining, power equipment manufacturing, oil & gas exploration, power trading &

distribution. NTPCis now in the entire power value chain and is poised to become an Integrated Power Major.

NTPC's share on 31 Mar 2008 in the total installed capacity of the country was 19.1% andit

contributed 28.50% of the total power generation of the country during 2007-08. NTPC has

set new benchmarks for the power industry both in the area of power plant construction and

operations. With its experience and expertise in the power sector, NTPC is extending

consultancyservices to various organizations in the power business. It provides consultancy in the area

of

power plant constructions and power generation to companies in India and abroad.

In November 2004, NTPC came out with its Initial Public Offering (IPO) consisting of

5.25% as fresh

issue and 5.25% as offer for sale by Government of India. NTPC thus became a listed

company with Government holding 89.5% of the equity share capital and rest held by

Institutional Investors and Public. The issue was a resounding success. NTPC is among the

largest five companies in India in terms of market capitalization.


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Growth Of NTPC Generation & PLF %

Recognizing its excellent performance and vast potential, Government of the India has

identified

NTPC as one of the jewels of Public Sector 'Navratnas'- a potential global giant. Inspired

by itsglorious past and vibrant present, NTPC is well on its way to realize its vision of being "A

world class

integrated power major, powering India's growth, with increasing global presence".


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VISION

Corporate vision: - A world class integrated power major, powering India's growthwith increasing global presence.

Mission :-Develop and provide reliable power related products and services at competitive

prices,

integrating multiple energy resources with innovative & Eco-friendly technologies andcontribution to the

society.

Core Values - BCOMIT

Business ethics

Customer Focus

Organizational & Professional Pride

Mutual Respect & Trust

Innovation & Speed

Total Quality for Excellence

A View Of Well Flourished Plant


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STRATEGIESSustainableDevelopmentMaintainsectorLeadershipFurther

EnchanceFuel SecurityExploitNewBusinessOpportunitiesTechnologyInitiativesNuturingHumanResource

STRATEGIES

Technological Initiatives

. Introduction of steam generators (boilers) of the size of 800 MW.

. Integrated Gasification Combined Cycle (IGCC) Technology.

. Launch of Energy Technology Center -A new initiative for development of technologieswith

focus on fundamental R&D.. The company sets aside up to 0.5% of the profits for R&D.

. Roadmap developed for adopting Clean Development.

. Mechanism to help get / earn Certified Emission Reduction.

Corporate Social Responsibility

. As a responsible corporate citizen NTPC has taken up number of CSR initiatives.

. NTPC Foundation formed to address Social issues at national level.

. NTPC has framed Corporate Social Responsibility Guidelines committing up to 0.5% ofnet

profit annually for Community Welfare Measures on perennial basis.

. The welfare of project affected persons and the local population around NTPC projectsare

taken care of through well drawn Rehabilitation and Resettlement policies.

. The company has also taken up distributed generation for remote rural areas.


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ENVIROMANTAL POLICY

NTPC is committed to the environment, generating power at minimal environmental costand

preserving the ecology in the vicinity of the plants. NTPC has undertaken massive a

forestation inthe vicinity of its plants. Plantations have increased forest area and reduced barren land.

The

massive a forestation by NTPC in and around its Ramagundam Power station (2600 MW)

havecontributed reducing the temperature in the areas by about 3c. NTPC has also taken

proactive

steps for ash utilization. In 1991, it set up Ash Utilization Division

A "Centre for Power Efficiency and Environment Protection- CENPEE" has been

established inNTPC with the assistance of United States Agency for International Development- USAID.

CENPEEP

is efficiency oriented, eco-friendly and eco-nurturing initiative - a symbol of NTPC'sconcern

towards environmental protection and continued commitment to sustainable power

development

in India.

As a responsible corporate citizen, NTPC is making constant efforts to improve the socio-

economicstatus of the people affected by its projects. Through its Rehabilitation and Resettlement

programmes, the company endeavors to improve the overall socio economic status Project

Affected Persons.

NTPC was among the first Public Sector Enterprises to enter into a Memorandum of

Understanding-

MOU with the Government in 1987-88. NTPC has been placed under the 'Excellentcategory' (the

best category) every year since the MOU system became operative.

Harmony between man and environment is the essence of healthy life and growth.

Therefore,maintenance of ecological balance and a pristine environment has been of utmost

importance to

NTPC. It has been taking various measures discussed below for mitigation of environment

pollution


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due to power generation.

NTPC is the second largest owner of trees in the country after the Forestdepartment.

Environment Policy & Environment Management System

Driven by its commitment for sustainable growth of power, NTPC has evolved a well

definedenvironment management policy and sound environment practices for minimizing

environmental

impact arising out of setting up of power plants and preserving the natural ecology.

NTPC Environment Policy

As early as in November 1995, NTPC brought out a comprehensive document entitled

"NTPCEnvironment Policy and Environment Management System". Amongst the guiding

principlesadopted in the document are company's proactive approach to environment, optimum

utilization

of equipment, adoption of latest technologies and continual environment improvement. Thepolicy

also envisages efficient utilization of resources, thereby minimizing waste, maximizing ash

utilization and providing green belt all around the plant for maintaining ecological balance.


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Environment Management, Occupational Health and Safety Systems:

NTPC has actively gone for adoption of best international practices on environment,

occupational

health and safety areas. The organization has pursued the Environmental ManagementSystem

(EMS) ISO 14001 and the Occupational Health and Safety Assessment System OHSAS

18001 at itsdifferent establishments. As a result of pursuing these practices, all NTPC power stations

have been

certified for ISO 14001 & OHSAS 18001 by reputed national and international Certifying

Agencies.

Pollution Control systems:

While deciding the appropriate technology for its projects, NTPC integrates manyenvironmental

provisions into the plant design. In order to ensure that NTPC comply with all thestipulated

environment norms, various state-of-the-art pollution control systems / devices as

discussed belowhave been installed to control air and water pollution.

Electrostatic Precipitators:

The ash left behind after combustion of coal is arrested in high efficiency Electrostatic

Precipitators

(ESPs) and particulate emission is controlled well within the stipulated norms. The ashcollected in

the ESPs is disposed to Ash Ponds in slurry form.

Flue Gas Stacks:

Tall Flue Gas Stacks have been provided for wide dispersion of the gaseous emissions

(SOX, NOXetc) into the atmosphere.

Low-NOX Burners:

In gas based NTPC power stations, NOx emissions are controlled by provision of Low-

NOx Burners(dry or wet type) and in coal fired stations, by adopting best combustion practices.

Neutralisation Pits:


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Neutralisation pits have been provided in the Water Treatment Plant (WTP) for pH

correction of the

effluents before discharge into Effluent Treatment Plant (ETP) for further treatment anduse.

Coal Settling Pits / Oil Settling Pits:

In these Pits, coal dust and oil are removed from the effluents emanating from the Coal

Handling

Plant (CHP), coal yard and Fuel Oil Handling areas before discharge into ETP.

DE & DS Systems:

Dust Extraction (DE) and Dust Suppression (DS) systems have been installed in all coal

fired powerstations in NTPC to contain and extract the fugitive dust released in the Coal Handling

Plant (CHP).


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Cooling Towers:

Cooling Towers have been provided for cooling the hot Condenser cooling water in closed

cycle

Condenser Cooling Water (CCW) Systems. This helps in reduction in thermal pollutionand

conservation of fresh water.

Ash Dykes & Ash Disposal systems:

Ash ponds have been provided at all coal based stations except Dadri where Dry Ash

DisposalSystem has been provided. Ash Ponds have been divided into lagoons and provided with

garlanding

arrangements for changeover of the ash slurry feed points for even filling of the pond and

foreffective settlement of the ash particles.

Ash in slurry form is discharged into the lagoons where ash particles get settled from the

slurry and

clear effluent water is discharged from the ash pond. The discharged effluents conform tostandards specified by CPCB and the same is regularly monitored.

At its Dadri Power Station, NTPC has set up a unique system for dry ash collection and

disposalfacility with Ash Mound formation. This has been envisaged for the first time in Asia

which has

resulted in progressive development of green belt besides far less requirement of land andless

water requirement as compared to the wet ash disposal system.

Ash Water Recycling System:

Further, in a number of NTPC stations, as a proactive measure, Ash Water Recycling

System (AWRS)has been provided. In the AWRS, the effluent from ash pond is circulated back to the

station for

further ash sluicing to the ash pond. This helps in savings of fresh water requirements fortransportation of ash from the plant.

The ash water recycling system has already been installed and is in operation atRamagundam,

Simhadri, Rihand, Talcher Kaniha, Talcher Thermal, Kahalgaon, Korba and Vindhyachal.

The scheme


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has helped stations to save huge quantity of fresh water required as make-up water for

disposal of

ash.

Dry Ash Extraction System (DAES):

Dry ash has much higher utilization potential in ash-based products (such as bricks, aerated

autoclaved concrete blocks, concrete, Portland pozzolana cement, etc.). DAES has been

installed atUnchahar, Dadri, Simhadri, Ramagundam, Singrauli, Kahalgaon, Farakka, Talcher

Thermal, Korba,

Vindhyachal, Talcher Kaniha and BTPS.

Liquid Waste Treatment Plants & Management System:

The objective of industrial liquid effluent treatment plant (ETP) is to discharge lesser and

cleanereffluent from the power plants to meet environmental regulations. After primary treatment

at the

source of their generation, the effluents are sent to the ETP for further treatment. Thecomposite

liquid effluent treatment plant has been designed to treat all liquid effluents which originate

within

the power station e.g. Water Treatment Plant (WTP), Condensate Polishing Unit (CPU)effluent,


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Coal Handling Plant (CHP) effluent, floor washings, service water drains etc. The scheme

involvescollection of various effluents and their appropriate treatment centrally and re-circulation of

the

treated effluent for various plant uses.

NTPC has implemented such systems in a number of its power stations such as

Ramagundam,Simhadri, Kayamkulam, Singrauli, Rihand, Vindhyachal, Korba, Jhanor Gandhar,

Faridabad, Farakka,

Kahalgaon and Talcher Kaniha. These plants have helped to control quality and quantity of

theeffluents discharged from the stations.

Sewage Treatment Plants & Facilities:

Sewage Treatment Plants (STPs) sewage treatment facilities have been provided at all

NTPC

stations to take care of Sewage Effluent from Plant and township areas. In a number ofNTPC

projects modern type STPs with Clarifloculators, Mechanical Agitators, sludge drying

beds, Gas

Collection Chambers etc have been provided to improve the effluent quality. The effluentquality is

monitored regularly and treated effluent conforming to the prescribed limit is discharged

from thestation. At several stations, treated effluents of STPs are being used for horticulture

purpose.

Environmental Institutional Set-up:

Realizing the importance of protection of the environment with speedy development of the

power

sector, the company has constituted different groups at project, regional and CorporateCentre

level to carry out specific environment related functions. The Environment Management

Group,Ash Utilisation Group and Centre for Power Efficiency & Environment Protection

(CENPEEP)

function from the Corporate Centre and initiate measures to mitigate the impact of power

project


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implementation on the environment and preserve ecology in the vicinity of the projects.

Environment Management and Ash Utilisation Groups established at each station, look

aftervarious environmental issues of the individual station.

Environment Reviews:

To maintain constant vigil on environmental compliance, Environmental Reviews are

carried out atall operating stations and remedial measures have been taken wherever necessary. As a

feedback

and follow-up of these Environmental Reviews, a number of retrofit and up-gradation

measureshave been undertaken at different stations.

Such periodic Environmental Reviews and extensive monitoring of the facilities carried out

at allstations have helped in compliance with the environmental norms and timely renewal of

the Airand Water Consents.

Waste Management

Various types of wastes such as Municipal or domestic wastes, hazardous wastes, Bio-

Medical

wastes get generated in power plant areas, plant hospital and the townships of projects. Thewastes generated are a number of solid and hazardous wastes like used oils & waste oils,

grease,


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lead acid batteries, other lead bearing wastes (such as garkets etc.), oil & clarifier sludge,

usedresin, used photo-chemicals, asbestos packing, e-waste, metal scrap, C&I wastes, electricial

scrap,

empty cylinders (refillable), paper, rubber products, canteen (bio-degradable) wastes,buidling

material wastes, silica gel, glass wool, fused lamps & tubes, fire resistant fluids etc. These

wastesfall either under hazardous wastes category or non-hazardous wastes category as per

classification

given in Government of Indias notification on Hazardous Wastes (Management and

Handling)Rules 1989 (as amended on 06.01.2000 & 20.05.2003). Handling and management of these

wastes

in NTPC stations have been discussed below.


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NTPC was set up in 1975 with 100%

ownership by the Government ofIndia. In the last 30 years, NTPC has

grown into the largest power utility in

India.1975In 1997, Government of India granted

NTPC status of Navratna"being one

of the nine jewels of India, enhancingthe powers to the Board of Directors.1997NTPC became a listed company with

majority Government ownership of

89.5%.

NTPC becomes 3rdlargest by MarketCapitalization of listed companies2004The company rechristened as NTPC

Limited in line with its changing

business portfolio and transforms

itself from a thermal power utility toan integrated power utility.

2005National Thermal Power Corporationis the largest power generation

company in India. Forbes Global 2000

for 2008 ranked it 411th in the world.2008EVOLUTION


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INTRODUCTION

BADARPUR THERMAL POWER STATION was established on 1973 and it was the part

of Central

Government. On 01/04/1978 is was given as No Loss No Profit Plant of NTPC.

Since then operating performance of NTPC has been considerably above the national

average. Theavailability factor for coal stations has increased from 85.03 % in 1997-98 to 90.09 % in

2006-07,

which compares favourably with international standards. The PLF has increased from

75.2% in1997-98 to 89.4% during the year 2006-07 which is the highest since the inception of

NTPC.

Capacity of BADARPUR THERMAL POWER STATION

Sr. No.

Capacity(MW)

Number

Total Capacity(MW)

1.

210

2

420

2.

95

3

285


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Overall Capacity- 705 MW

BASIC PRINCIPLE

As per FARADAYs Law- Whenever the amount of magnetic flux linked with a circuit

changes, an EMF is

produced in the circuit. Generator works on the principle of producing electricity. Tochange the flux in the

generator turbine is moved in a great speed with steam.

To produce steam, water is heated in the boilers by burning the coal. In a BadarpurThermal Power

Station, steam is produced and used to spin a turbine that operates a generator. Water is

heated,

turns into steam and spins a steam turbine which drives an electrical generator. After itpasses

through the turbine, the steam is condensed in a condenser; this is known as a Rankinecycle.

Shown here is a diagram of a conventional thermal power plant, which uses coal, oil, or

natural gasas fuel to boil water to produce the steam. The electricity generated at the plant is sent to

consumers through high-voltage power lines The Badarpur Thermal Power Plant has Steam

Turbine-Driven Generators which has a collective capacity of 705MW. The fuel being used

is Coalwhich is supplied from the Jharia Coal Field in Jharkhand. Water supply is given from the

Agra

Canal.


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Heat Enegrgy

SteamCoupling

Electricity from Coal

There are basically three main units of a thermal power plant:

1. Steam Generator or Boiler

2. Steam Turbine

3. Electric Generator

Basic Electricity Generation Chart


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Functioning of Thermal Power Plant

Typical Diagram of Coal Based Power Plant

Its various parts are listed below:-

1. Cooling tower

2. Cooling water pump

3. Transmission line (3-phase)

4. Unit transformer (3-phase)

5. Electric generator (3-phase)

6. Low pressure turbine

7. Condensate extraction pump

8. Condenser


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9. Intermediate pressure turbine

10. Steam governor valve

11. High pressure turbine

12. DE aerator

13. Feed heater

14. Coal conveyor

15. Coal hopper

16. Pulverised fuel mill

17. Boiler drum

18. Ash hopper

19. Super heater

20. Forced draught fan

21. Re heater

22. Air intake

23. Economiser

24. Air preheater

25. Precipitator

26. Induced draught fan

27. Fuel Gas Stack


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1. Cooling towers

Cooling Towers are evaporative coolers used for cooling water or other working mediumto near the

ambivalent web-bulb air temperature. Cooling tower use evaporation of water to reject heat

fromprocesses such as cooling the circulating water used in oil refineries, Chemical plants,

power plants

and building cooling, for example. The tower vary in size from small roof-top units to verylarge

hyperboloid structures that can be up to 200 meters tall and 100 meters in diameter, or

rectangular

structure that can be over 40 meters tall and 80 meters long. Smaller towers are normallyfactory

built, while larger ones are constructed on site.

The primary use of large , industrial cooling tower system is to remove the heat absorbed in

thecirculating cooling water systems used in power plants , petroleum refineries,

petrochemical andchemical plants, natural gas processing plants and other industrial facilities . The absorbed

heat is

rejected to the atmosphere by the evaporation of some of the cooling water in mechanicalforced-

draft or induced draft towers or in natural draft hyperbolic shaped cooling towers as seen at

most

nuclear power plants.

2. Cooling Water Pump

It pumps the water from the cooling tower which goes to the condenser.

3.Three phase transmission line

Three phase electric power is a common method of electric power transmission. It is a type

ofpolyphase system mainly used to power motors and many other devices. A Three phase

system uses

less conductor material to transmit electric power than equivalent single phase, two phase,or direct

current system at the same voltage. In a three phase system, three circuits reach their

instantaneouspeak values at different times. Taking one conductor as the reference, the other two current

are

delayed in time by one-third and two-third of one cycle of the electrical current. This delay

between


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phases has the effect of giving constant power transfer over each cycle of the current and

also

makes it possible to produce a rotating magnetic field in an electric motor.At the power station, an electric generator converts mechanical power into a set of electric

currents,

one from each electromagnetic coil or winding of the generator. The current are sinusoidalfunctions

of time, all at the same frequency but offset in time to give different phases. In a three

phase systemthe phases are spaced equally, giving a phase separation of one-third one cycle. Generators

output at

a voltage that ranges from hundreds of volts to 30,000 volts.

4. Unit transformer (3-phase)

At the power station, transformers: step-up this voltage to one more suitable for

transmission. Afternumerous further conversions in the transmission and distribution network the power is

finallytransformed to the standard mains voltage (i.e. the household voltage).

The power may already have been split into single phase at this point or it may still be three

phase.Where the step-down is 3 phase, the output of this transformer is usually star connected

with the

standard mains voltage being the phase-neutral voltage. Another system commonly seen in

NorthAmerica is to have a delta connected secondary with a center tap on one of the windings

supplying

the ground and neutral. This allows for 240 V three phase as well as three different singlephase

voltages( 120 V between two of the phases and neutral , 208 V between the third phase

( known as awild leg) and neutral and 240 V between any two phase) to be available from the same

supply.


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5. Electrical generator

An Electrical generator is a device that converts kinetic energy to electrical energy,generally using

electromagnetic induction. The task of converting the electrical energy into mechanical

energy isaccomplished by using a motor. The source of mechanical energy may be a reciprocating or

turbine

steam engine, , water falling through the turbine are made in a variety of sizes ranging fromsmall 1

hp (0.75 kW) units (rare) used as mechanical drives for pumps, compressors and other shaft

driven

equipment , to 2,000,000 hp(1,500,000 kW) turbines used to generate electricity. There areseveral

classifications for modern steam turbines.

Steam turbines are used in all of our major coal fired power stations to drive the generators

oralternators, which produce electricity. The turbines themselves are driven by steam

generated inBoilers. or steam generators. as they are sometimes called.

Electrical power station use large stem turbines driving electric generators to produce most

(about86%) of the world.s electricity. These centralized stations are of two types: fossil fuel

power plants

and nuclear power plants. The turbines used for electric power generation are most often

directlycoupled to their-generators .As the generators must rotate at constant synchronous speeds

according

to the frequency of the electric power system, the most common speeds are 3000 r/min for50 Hz

systems, and 3600 r/min for 60 Hz systems. Most large nuclear sets rotate at half those

speeds, andhave a 4-pole generator rather than the more common 2-pole one.

6. Low Pressure TurbineEnergy in the steam after it leaves the boiler is converted into rotational energy as it passes

through

the turbine. The turbine normally consists of several stage with each stages consisting of astationary

blade (or nozzle) and a rotating blade. Stationary blades convert the potential energy of the

steaminto kinetic energy into forces, caused by pressure drop, which results in the rotation of the

turbine

shaft. The turbine shaft is connected to a generator, which produces the electrical energy.


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Low Pressure Turbine (LPT) consist of 4x2 stages. After passing through Intermediate

Pressure

Turbine is is passed through LPT which is made up of two parts- LPC REAR & LPCFRONT. As

water gets cooler here it gathers into a HOTWELL placed in lower parts of Turbine.

7. Condensation Extraction PumpA Boiler feed water pump is a specific type of pump used to pump water into a steam

boiler. The

water may be freshly supplied or retuning condensation of the steam produced by theboiler. These

pumps are normally high pressure units that use suction from a condensate return system

and can be

of the centrifugal pump type or positive displacement type.Construction and operation

Feed water pumps range in size up to many horsepower and the electric motor is usually

separated

from the pump body by some form of mechanical coupling. Large industrial condensatepumps may

also serve as the feed water pump. In either case, to force the water into the boiler; thepump must

generate sufficient pressure to overcome the steam pressure developed by the boiler. This is

usuallyaccomplished through the use of a centrifugal pump.

Feed water pumps usually run intermittently and are controlled by a float switch or other

similar

level-sensing device energizing the pump when it detects a lowered liquid level in theboiler is

substantially increased. Some pumps contain a two-stage switch. As liquid lowers to the

trigger pointof the first stage, the pump is activated. I f the liquid continues to drop (perhaps because

the pump

has failed, its supply has been cut off or exhausted, or its discharge is blocked); the secondstage will


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be triggered. This stage may switch off the boiler equipment (preventing the boiler from

running dryand overheating), trigger an alarm, or both.

8. Condenser

The steam coming out from the Low Pressure Turbine (a little above its boiling pump) is

brought

into thermal contact with cold water (pumped in from the cooling tower) in the condenser,

where itcondenses rapidly back into water, creating near

vacuum-like conditions inside the condenser chest.

9. Intermediate Pressure Turbine

Intermediate Pressure Turbine (IPT) consist of 11 stages. When the steam has been passedthrough

HPT it gets enter into IPT. IPT has two ends named as FRONT & REAR. Steam enters

through front

end and leaves from Rear end.

10. Steam Governor ValveSteam locomotives and the steam engines used on ships and stationary applications such as

power

plants also required feed water pumps. In this situation, though, the pump was oftenpowered using a

small steam engine that ran using the steam produced by the boiler. A means had to be

provided, of

course, to put the initial charge of water into the boiler(before steam power was available tooperate

the steam-powered feed water pump).the pump was often a positive displacement pump

that hadsteam valves and cylinders at one end and feed water cylinders at the other end; no

crankshaft was

required.In thermal plants, the primary purpose of surface condenser is to condense the exhaust

steam from a

steam turbine to obtain maximum efficiency and also to convert the turbine exhaust steam

into pure


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water so that it may be reused in the steam generator or boiler as boiler feed water. By

condensing

the exhaust steam of a turbine at a pressure below atmospheric pressure, the steam pressuredrop

between the inlet and exhaust of the turbine is increased, which increases the amount heat

availablefor conversion to mechanical power. Most of the heat liberated due to condensation of the

exhaust

steam is carried away by the cooling medium (water or air) used by the surface condenser.Control valves are valves used within industrial plants and elsewhere to control operating

conditions

such as temperature,pressure,flow,and liquid Level by fully partially opening or closing in

responseto signals received from controllers that compares a set point to a process variable

whose value

is provided by sensors that monitor changes in such conditions. The opening or closing of

controlvalves is done by means of electrical, hydraulic or pneumatic systems

11.High Pressure Turbine

Steam coming from Boiler directly feeds into HPT at a temperature of 540C and at a

pressure of136 kg/cm2. Here it passes through 12 different stages due to which its temperature goes

down to

329C and pressure as 27 kg/cm2. This line is also called as CRH COLD REHEAT

LINE.


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It is now passed to an REHEATER where its temperature rises to 540C and called as

HRH-HOTREHEATED LINE .

12. DeaeratorA Dearator is a device for air removal and used to remove dissolved gases (an alternate

would be the

use of water treatment chemicals) from boiler feed water to make it non-corrosive. Adearator

typically includes a vertical domed deaeration section as the deaeration boiler feed water

tank. A

Steam generating boiler requires that the circulating steam, condensate, and feed watershould be

devoid of dissolved gases, particularly corrosive ones and dissolved or suspended solids.

The gases

will give rise to corrosion of the metal. The solids will deposit on the heating surfacesgiving rise to

localized heating and tube ruptures due to overheating. Under some conditions it may giveto stress

corrosion cracking.

Deaerator level and pressure must be controlled by adjusting control valves- the level byregulating

condensate flow and the pressure by regulating steam flow. If operated properly, most

deaerator

vendors will guarantee that oxygen in the deaerated water will not exceed 7 ppb by weight(0.005

cm3/L)

13. Feed water heaterA Feed water heater is a power plant component used to pre-heat water delivered to a

steam

generating boiler. Preheating the feed water reduces the irreversible involved in steamgeneration and

therefore improves the thermodynamic efficiency of the system.[4] This reduces plant

operating

costs and also helps to avoid thermal shock to the boiler metal when the feed water isintroduces

back into the steam cycle.

In a steam power (usually modelled as a modified Ranking cycle), feed water heaters allowthe feed

water to be brought up to the saturation temperature very gradually. This minimizes the

inevitableirreversibility.s associated with heat transfer to the working fluid (water). A belt conveyor

consists of

two pulleys, with a continuous loop of material- the conveyor Belt that rotates about

them. The


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pulleys are powered, moving the belt and the material on the belt forward. Conveyor belts

are

extensively used to transport industrial and agricultural material, such as grain, coal, oresetc.

14. Coal conveyor

Coal conveyors are belts which are used to transfer coal from its storage place to Coal

Hopper.

15. Coal Hopper

Coal Hopper are the places which are used to feed coal to Fuel Mill. It also has the

arrangement of enteringof Hoy Air at 200C inside it which solves our two purposes:-

1. If our Coal has moisture content then it dries it so that a proper combustion takes place.

2. It raises the temperature of coal so that its temperature is more near to its IgniteTemperature so

that combustion is easy.


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16. Pulverised Fuel Mill

A pulveriser is a device for grinding coal for combustion in a furnace in a fossil fuel power

plant.

17. Boiler DrumSteam Drums are a regular feature of water tube boilers. It is reservoir of water/steam at the

top end

of the water tubes in the water-tube boiler. They store the steam generated in the watertubes and act

as a phase separator for the steam/water mixture. The difference in densities between hot

and cold

water helps in the accumulation of the hotter-water/and saturated steam into steamdrum. Made

from high-grade steel (probably stainless) and its working involves temperatures 390.C and

pressure

well above 350psi (2.4MPa). The separated steam is drawn out from the top section of thedrum.

Saturated steam is drawn off the top of the drum. The steam will re-enter the furnace inthrough a

super heater, while the saturated water at the bottom of steam drum flows down to the

mud-drum/feed water drum by down comer tubes accessories include a safety valve, water level

indicator and

fuse plug.

18. Ash Hopper

A steam drum is used in the company of a mud-drum/feed water drum which is located at alower

level. So that it acts as a sump for the sludge or sediments which have a tendency to the

bottom.19. Super Heater

A Super heater is a device in a steam engine that heats the steam generated by the boiler

again

increasing its thermal energy and decreasing the likelihood that it will condense inside theengine.

Super heaters increase the efficiency of the steam engine, and were widely adopted. Steam

which hasbeen superheated is logically known as superheated steam; non-superheated steam is called

saturated

steam or wet steam; Super heaters were applied to steam locomotives in quantity from theearly 20th

century, to most steam vehicles, and so stationary steam engines including power stations.


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20. Force Draught Fan

External fans are provided to give sufficient air for combustion. The forced draft fan takesair from

the atmosphere and, first warming it in the air preheater for better combustion, injects it via

the airnozzles on the furnace wall.

21. Reheater

Reheater are heaters which are used to raise the temperature of air which has been fallen

down due to

various process.

22. Air Intake

Air is taken from the environment by an air intake tower.

23. Economizers

Economizer, or in the UK economizer, are mechanical devices intended to reduce energy

consumption, or to perform another useful function like preheating a fluid. The termeconomizer is

used for other purposes as well. Boiler, power plant, and heating, ventilating and air

conditioning. In


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boilers, economizer are heat exchange devices that heat fluids , usually water, up to but not

normallybeyond the boiling point of the fluid. Economizers are so named because they can make

use of the

enthalpy and improving the boiler.s efficiency. They are a device fitted to a boiler whichsaves

energy by using the exhaust gases from the boiler to preheat the cold water used the fill it

(the feedwater). Modern day boilers, such as those in cold fired power stations, are still fitted with

economizer which is decedents of Green.s original design. In this context they are turbines

before it

is pumped to the boilers. A common application of economizer is steam power plants is tocapture

the waste hit from boiler stack gases (flue gas) and transfer thus it to the boiler feed water

thus

lowering the needed energy input , in turn reducing the firing rates to accomplish the ratedboiler

output . Economizer lower stack temperatures which may cause condensation of acidiccombustion

gases and serious equipment corrosion damage if care is not taken in their design and

materialselection.

24. Air Preheater

Air preheater is a general term to describe any device designed to heat air before another

process (forexample, combustion in a boiler). The purpose of the air preheater is to recover the heat

from the

boiler flue gas which increases the thermal efficiency of the boiler by reducing the usefulheat lost in

the fuel gas. As a consequence, the flue gases are also sent to the flue gas stack (or

chimney) at alower temperature allowing simplified design of the ducting and the flue gas stack. It also

allows

control over the temperature of gases leaving the stack.

25. PrecipitatorAn Electrostatic precipitator (ESP) or electrostatic air cleaner is a particulate device that

removes

particles from a flowing gas (such As air) using the force of an induced electrostaticcharge.

Electrostatic precipitators are highly efficient filtration devices, and can easily remove fine

particulate matter such as dust and smoke from the air steam.ESP.s continue to be excellent devices for control of many industrial particulate emissions,

including

smoke from electricity-generating utilities (coal and oil fired), salt cake collection from

black liquor


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boilers in pump mills, and catalyst collection from fluidized bed catalytic crackers from

several

hundred thousand ACFM in the largest coal-fired boiler application.The original parallel plate-Weighted wire design (described above) has evolved as more

efficient (

and robust) discharge electrode designs were developed, today focusing on rigid dischargeelectrodes

to which many sharpened spikes are attached , maximizing corona production. Transformer

rectifiersystems apply voltages of 50-100 Kilovolts at relatively high current densities. Modern

controls

minimize sparking and prevent arcing, avoiding damage to the components. Automatic

rappingsystems and hopper evacuation systems remove the collected particulate matter while on

line

allowing ESP.s to stay in operation for years at a time.

26. Induced Draught Fan

The induced draft fan assists the FD fan by drawing out combustible gases from the

furnace,

maintaining a slightly negative pressure in the furnace to avoid backfiring through any

opening. At

the furnace outlet, and before the furnace gases are handled by the ID fan, fine dust carriedby the

outlet gases is removed to avoid atmospheric pollution. This is an environmental limitation

prescribed by law, additionally minimizes erosion of the ID fan.


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27. Fuel gas stack

A Fuel gas stack is a type of chimney, a vertical pipe, channel or similar structure throughwhich combustion

product gases called fuel gases are exhausted to the outside air. Fuel gases are produced

when coal, oil,natural gas, wood or any other large combustion device. Fuel gas is usually composed of

carbon dioxide

(CO2) and water vapor as well as nitrogen and excess oxygen remaining from the intakecombustion air. It

also contains a small percentage of pollutants such as particulates matter, carbon mono

oxide, nitrogen

oxides and sulfur oxides. The flue gas stacks are often quite tall, up to 400 meters (1300feet) or more, so as

to disperse the exhaust pollutants over a greater aria and thereby reduce the concentration

of the pollutants

to the levels required by governmental environmental policies and regulations.When the fuel gases exhausted from stoves, ovens, fireplaces or other small sources within

residentialabodes, restaurants , hotels or other stacks are referred to as chimneys.

OPERATION OF BOILER

The boiler is a rectangular furnace about 50 ft (15 m) on a side and 130 ft (40 m) tall. Its

walls are

made of a web of high pressure steel tubes about 2.3 inches (60 mm) in diameter.

Pulverized coal is air-blown into the furnace from fuel nozzles at the four corners and it

rapidly

burns, forming a large fireball at the center. The thermal radiation of the fireball heats thewater

that circulates through the boiler tubes near the boiler perimeter. The water circulation rate

in theboiler is three to four times the throughput and is typically driven by pumps. As the water

in the

boiler circulates it absorbs heat and changes into steam at 700 F (370 C) and 22.1 MPa. It

is


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separated from the water inside a drum at the top of the furnace. The saturated steam is

introduced into superheat pendant tubes that hang in the hottest part of the combustion

gases asthey exit the furnace. Here the steam is superheated to 1,000 F (540 C) to prepare it for

the

turbine.

The steam generating boiler has to produce steam at the high purity, pressure and

temperaturerequired for the steam turbine that drives the electrical generator. The generator includes

the

economizer, the steam drum, the chemical dosing equipment, and the furnace with its

steamgenerating tubes and the superheater coils. Necessary safety valves are located at suitable

pointsvto avoid excessive boiler pressure. The air and flue gas path equipment include:

forced draft

(FD) fan, air preheater (APH), boiler furnace, induced draft (ID) fan, fly ash collectors(electrostatic

precipitator or baghouse) and the flue gas stack.


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Schematic diagram of a coal-fired power plant steam generator

Boiler Furnace and Steam Drum

Once water inside the boiler or steam generator, the process of adding the latent heat of

vaporization or enthalpy is underway. The boiler transfers energy to the water by the

chemicalreaction of burning some type of fuel.

The water enters the boiler through a section in the convection pass called the economizer.

Fromthe economizer it passes to the steam drum. Once the water enters the steam drum it goes

downthe down comers to the lower inlet water wall headers. From the inlet headers the water

rises

through the water walls and is eventually turned into steam due to the heat being generatedby the

burners located on the front and rear water walls (typically). As the water is turned into

steam/vapour in the water walls, the steam/vapor once again enters the steam drum.

Fuel Preparation System

In coal-fired power stations, the raw feed coal from the coal storage area is first crushedinto small

pieces and then conveyed to the coal feed hoppers at the boilers. The coal is next

pulverized into a very fine powder. The pulverizers may be ball mills, rotating drum

grinders, or

other types of grinders.

Some power stations burn fuel oil rather than coal. The oil must kept warm (above its pour

point) in the fuel oil storage tanks to prevent the oil from congealing and becoming un-pumpable.

The oil is usually heated to about 100C before being pumped through the furnace fuel oil

spraynozzles.


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Fuel Firing System and Ignite System

From the pulverized coal bin, coal is blown by hot air through the furnace coal burners atan

angle which imparts a swirling motion to the powdered coal to enhance mixing of the coal

powder with the incoming preheated combustion air and thus to enhance the combustion.

To provide sufficient combustion temperature in the furnace before igniting the powdered

coal, the

furnace temperature is raised by first burning some light fuel oil or processed natural gas

(by usingauxiliary burners and igniters provide for that purpose).


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Air Path

External fans are provided to give sufficient air for combustion. The forced draft fan takes

air from

the atmosphere and, first warming it in the air preheater for better combustion, injects it viathe air

nozzles on the furnace wall.

The induced draft fan assists the FD fan by drawing out combustible gases from the

furnace,

maintaining a slightly negative pressure in the furnace to avoid backfiring through anyopening. At

the furnace outlet, and before the furnace gases are handled by the ID fan, fine dust carried

by the

outlet gases is removed to avoid atmospheric pollution. This is an environmental limitationprescribed by law, and additionally minimizes erosion of the ID fan.

Fly Ash Collection

Fly ash is captured and removed from the flue gas by electrostatic precipitators or fabric

bag

filters (or sometimes both) located at the outlet of the furnace and before the induced draft

fan.

The fly ash is periodically removed from the collection hoppers below the precipitators orbag

filters. Generally, the fly ash is pneumatically transported to storage silos for subsequent

transportby trucks or railroad cars.

Bottom Ash Collection and Disposal

At the bottom of every boiler, a hopper has been provided for collection of the bottom ash

from

the bottom of the furnace. This hopper is always filled with water to quench the ash andclinkers

falling down from the furnace. Some arrangement is included to crush the clinkers and for

conveying the crushed clinkers and bottom ash to a storage site.

Boiler Make-up Water Treatment Plant and Storage


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Since there is continuous withdrawal of steam and continuous return of condensate to the

boiler,

losses due to blow-down and leakages have to be made up for so as to maintain the desiredwater

level in the boiler steam drum. For this, continuous make-up water is added to the boiler

watersystem. The impurities in the raw water input to the plant generally consist of calcium and

magnesium salts which impart hardness to the water. Hardness in the make-up water to the

boilerwill form deposits on the tube water surfaces which will lead to overheating and failure of

the

tubes. Thus, the salts have to be removed from the water and that is done by a water

demineralising treatment plant (DM).

OPERATION OF TURBINE

Steam turbines are used in all of our major coal fired power stations to drive the generators

oralternators, which produce electricity. The turbines themselves are driven by steam

generated in

'Boilers' or 'Steam Generators' as they are sometimes called. Energy in the steam after it

leaves theboiler is converted into rotational energy as it passes through the turbine. The turbine

normally

consists of several stages with each stage consisting of a stationary blade (or nozzle) and arotating

blade. Stationary blades convert the potential energy of the steam (temperature and

pressure) intokinetic energy (velocity) and direct the flow onto the rotating blades. The rotating blades

convert

the kinetic energy into forces, caused by pressure drop, which results in the rotation of the

turbineshaft. The turbine shaft is connected to a generator, which produces the electrical energy.

The


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rotational speed is 3000 rpm for Indian System (50 Hz) systems and 3600 for American (60

Hz)systems.

In a typical larger power stations, the steam turbines are split into three separate stages, thefirst

being the High Pressure (HP), the second the Intermediate Pressure (IP) and the third the

LowPressure (LP) stage, where high, intermediate and low describe the pressure of the steam.

After

the steam has passed through the HP stage, it is returned to the boiler to be re-heated to its

original temperature although the pressure remains greatly reduced. The reheated steamthen

passes through the IP stage and finally to the LP stage of the turbine.

High-pressure oil is injected into the bearings to provide lubrication.


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VARIOUS CYCLES AT POWER

STATION

. COAL CYCLE

. CONDENSATE CYCLE

. FEED WATER CYCLE

. STEAM CYCLE


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Coal Stock

YardRC BunkerRC FeederMillFurnace

COAL CYCLE


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From LP

TurbinecondensorCondensatePumpEjectorGlandSteamLPH1LPH2LPH3Dearrator

Condensate Cycle


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Boiler Feed

PumpHPH5HPH6HPH7Feed WaterLineEconomizerBoiler

DrumDown

CornerWaterFFED WATER CYCLE


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From Boiler

DrumLT SuperHeaterFinal HeaterMain Steam

LineHP TurbineCold Reheat

LineReheaterHot ReheatLineLow pressure

LineTo

CondensorSTEAM CYCLE


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CONTROL & INSTRUMENTATION

. INTRODUCTION

. C&I LABS

. CONTROL & MONITORING MECHENISM

. PRESSURE MONITORING

. TEMPERATURE MONITORING

. FLOW MEASUREMENT

. CONTROL VALVES


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INTRODUCTION

This division basically calibrates various instruments and takes care of any faults occur in

any of the

auxiliaries in the plant.

Instrumentation can be well defined as a technology of using instruments to measure and

control the physical and chemical properties of a material.

C&I LABS

Control and Instrumentation Department has following labs:

1. Manometry Lab

2. Protection and Interlocks Lab

3. Automation Lab4. Electronics Lab

5. Water Treatment Plant6. Furnaces Safety Supervisory System Lab

OPERATION AND MAINTAINANCE

Control and Instrumentation Department has following Control Units:

1. Unit Control Board

2. Main Control Board

3. Analog & Digital Signal Control4. Current Signal Control

This department is the brain of the plant because from the relays to transmitters followed

by the

electronic computation chipsets and recorders and lastly the controlling circuitry, all fall

underthis.

A View of Control Room at BTPS


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1. Manometry Lab

TRANSMITTERS

It is used for pressure measurements of gases and liquids, its working principle is that theinput

pressure is converted into electrostatic capacitance and from there it is conditioned and

amplified. Itgives an output of 4-20 ma DC. It can be mounted on a pipe or a wall. For liquid or steam

measurement transmitters is mounted below main process piping and for gas measurement

transmitter is placed above pipe.

MANOMETER

Its a tube which is bent, in U shape. It is filled with a liquid. This device corresponds to a

differencein pressure across the two limbs.

BOURDEN PRESSURE GAUGE

Its an oval section tube. Its one end is fixed. It is provided with a pointer to indicate the

pressure

on a calibrated scale. It is of 2 types:

(a) Spiral type: for Low pressure measurement.

(b) Helical Type: for High pressure measurement.

While selecting Pressure Gauge these parameters should keep in mind-

1. Accuracy

2. Safety

3. Utility4. Price

ACCURACY

Higher Accuracy implies Larger Dial Size for accuracy of small and readable pressurescale

increments.

SAFETY


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While selecting Pressure Gauge it should consider that Gauge Construction Material should

bechemically compatible with the environment either inside or outside it.

UTILITY

It should keep it mind that range of the Gauge should be according to our need else

OverpressureFailure may occur resulting in damage of Gauge.

PRICE

Lager the Gauges Dial size larger would be our price. Better Gauges Construction

material also

increses the cost. So they must be chosen according to our need.


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2. Protection and Interlock Lab

INTERLOCKING

It is basically interconnecting two or more equipments so that if one equipment fails otherone can

perform the tasks. This type of interdependence is also created so that equipments

connectedtogether are started and shut down in the specific sequence to avoid damage. For protection

of

equipments tripping are provided for all the equipments. Tripping can be considered as the

seriesof instructions connected through OR GATE, which trips the circuit. The main equipments

of this lab

are relay and circuit breakers. Some of the instrument uses for protection are:.

RELAY

It is a protective device. It can detect wrong condition in electrical circuits by constantly

measuring

the electrical quantities flowing under normal and faulty conditions. Some of the electricalquantities are voltage, current, phase angle and velocity. 2. FUSES It is a short piece of

metal

inserted in the circuit, which melts when heavy current flows through it and thus breaks the

circuit.

Usually silver is used as a fuse material because:

a) The coefficient of expansion of silver is very small. As a result no critical fatigue occurs

and

thus the continuous full capacity normal current ratings are assured for the long time.b) The conductivity of the silver is unimpaired by the surges of the current that produces

temperatures just near the melting point.

c) Silver fusible elements can be raised from normal operating temperature to vaporization

quicker than any other material because of its comparatively low specific heat.

Miniature Circuit Breaker-

They are used with combination of the control circuits to.

a) Enable the staring of plant and distributors.

b) Protect the circuit in case of a fault. In consists of current carrying contacts, one movable

and other fixed. When a fault occurs the contacts separate and are is stuck between them.

There are three types of trips


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I. MANUAL TRIP

II. THERMAL TRIP

III. SHORT CIRCUIT TRIP.

Protection and Interlock System-

1. HIGH TENSION CONTROL CIRCUIT for high tension system the control system are

excited byseparate D.C supply. For starting the circuit conditions should be in series with the starting

coil of the equipment to energize it. Because if even a single condition is not true then

system will not start.

2. LOW TENSION CONTROL CIRCUIT For low tension system the control circuits aredirectly

excited from the 0.415 KV A.C supply.

The same circuit achieves both excitation and tripping. Hence the tripping coil is provided

foremergency tripping if the interconnection fails.


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3. AUTOMATION LAB

This lab deals in automating the existing equipment and feeding routes. Earlier, the old

technology

dealt with only (DAS) Data Acquisition System and came to be known as primary systems.The

modern technology or the secondary systems are coupled with (MIS) Management

InformationSystem. But this lab universally applies the pressure measuring instruments as the

controlling force.

However, the relays are also provided but they are used only for protection and interlocks.

4. PYROMETRY LAB

LIQUID IN GLASS THERMOMETER

Mercury in the glass thermometer boils at 340 C which limits the range of temperature

that canbe measured. It is L shaped thermometer which is designed to reach all inaccessible places.

1. ULTRA VIOLET CENSOR-

This device is used in furnace and it measures the intensity of ultra violet rays there and

according

to the wave generated which directly indicates the temperature in the furnace.

2, THERMOCOUPLES

This device is based on SEEBACK and PELTIER effect. It comprises of two junctions at

different

temperature. Then the emf is induced in the circuit due to the flow of electrons. This is animportant part in the plant.

3. RTD (RESISTANCE TEMPERATURE DETECTOR)

It performs the function of thermocouple basically but the difference is of a resistance. In

this due

to the change in the resistance the temperature difference is measured. In this lab, also themeasuring devices can be calibrated in the oil bath or just boiling water (for low range

devices) and

in small furnace (for high range devices).

5. FURNACE SAFETY AND SUPERVISORY SYSTEM LAB


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This lab has the responsibility of starting fire in the furnace to enable the burning of coal.

For first

stage coal burners are in the front and rear of the furnace and for the second and third stagecorner

firing is employed. Unburnt coal is removed using forced draft or induced draft fan. The

temperature inside the boiler is 1100C and its heights 18 to 40 m. It is made up of mildsteel. An

ultra violet sensor is employed in furnace to measure the intensity of ultra violet rays inside

thefurnace and according to it a signal in the same order of same mV is generated which

directly

indicates the temperature of the furnace. For firing the furnace a 10 KV spark plug is

operated forten seconds over a spray of diesel fuel and pre-heater air along each of the feeder-mills.

The

furnace has six feeder mills each separated by warm air pipes fed from forced draft fans. In

firststage indirect firing is employed that is feeder mills are not fed directly from coal but are

fed fromthree feeders but are fed from pulverized coalbunkers. The furnace can operate on the

minimum

feed from three feeders but under no circumstances should anyone be left out underoperation, to

prevent creation of pressure different with in the furnace, which threatens to blast it.


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6. ELECTRONICS LAB

This lab undertakes the calibration and testing of various cards. It houses various types of

analytical

instruments like oscilloscopes, integrated circuits, cards auto analyzers etc.Various processes undertaken in this lab are:

1. Transmitter converts mV to mA.

2. Auto analyzer purifies the sample before it is sent to electrodes. It extracts the magneticportion.

ANNUNCIATIN CARDSThey are used to keep any parameter like temperature etc. within limits. It gets a signal if

parameter goes beyond limit. It has a switching transistor connected to relay that helps in

alerting

the UCB.

CONTROL & MONITORING MECHANISMS

There are basically two types of Problems faced in a Power Plant

1. Metallurgical

2. Mechanical

Mechanical Problem can be related to Turbines that is the max speed permissible for a

turbine is

3000 rpm so speed should be monitored and maintained at that level.

Metallurgical Problem can be view as the max Inlet Temperature for Turbine is 1060 C so

temperature should be below the limit. Monitoring of all the parameters is necessary for thesafety

of both:

1. Employees2. Machines

So the Parameters to be monitored are:

1. Speed

2. Temperature

3. Current


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4. Voltage

5. Pressure

6. Eccentricity

7. Flow of Gases

8. Vacuum Pressure

9. Valves

10. Level


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11. Vibration

PRESSURE MONITORING

Pressure can be monitored by three types of basic mechanisms

1. Switches

2. Gauges

3. Transmitter type

For gauges we use Bourdon tubes. The Bourdon Tube is a non-liquid pressure

measurement device.It is widely used in applications where inexpensive static pressure measurements are

needed.

A typical Bourdon tube contains a curved tube that is open to external pressure input on

one end and is coupled mechanically to an indicating needle on the other end, as shown

schematically below.

Typical Bourdon Tube Pressure Gages

For Switches pressure switches are used and they can be used for digital means of

monitoring as

switch being ON is referred as high and being OFF is as low.

All the monitored data is converted to either Current or Voltage parameter.

The Plant standard for current and voltage are as under

Voltage : 0 10 Volts range


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Current : 4 20 milli-Amperes


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We use 4mA as the lower value so as to check for disturbances and wire breaks.

Accuracy of such systems is very high.

ACCURACY : 0.1 %

Programmable Logic Circuits (PLCs) are used in the process as they are the heart of

Instrumentation.

TEMPERATURE MONITORING

We can use Thermocouples or RTDs for temperature monitoring. Normally RTDs are usedfor low

temperatures.

Thermocouple selection depends upon two factors:

1. Temperature Range2. Accuracy Required

Normally used Thermocouple is K Type Thermocouple:

In this we use Chromel (Nickel-Chromium Alloy) / Alumel (Nickel-Aluminium Alloy) as

two metals.This is the most commonly used general purpose thermocouple. It is inexpensive and,

owing to its

popularity, available in a wide variety of probes. They are available in the-200C to+1200C range.

Sensitivity is approximately 41 V/C.

RTDs are also used but not in protection systems due to vibrational errors.


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We pass a constant current through the RTD. So that if R changes then the Voltage also

changes

RTDs used in Industries are Pt100 and Pt1000

Pt100 : 0C 100 O ( 1 O = 2.5 0C )

Pt1000 : 0C - 1000O

Pt1000 is used for higher accuracy.

The gauges used for Temperature measurements are mercury filled Temperature gauges.

For Analog medium thermocouples are used and for Digital medium Switches are used

which are

basically mercury switches.


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FLOW MEASUREMENT

Flow measurement does not signify much and is measured just for metering purposes and

for monitoring the processes

ROTAMETERS:

A Rotameter is a device that measures the flow rate of liquid or gas in a closed tube. It

isoccasionally misspelled as 'Rotometer'.

It belongs to a class of meters called variable area meters, which measure flow rate by

allowing the

cross sectional area the fluid travels through to vary, causing some measurable effect.

A rotameter consists of a tapered tube, typically made of glass, with a float inside that is

pushed up

by flow and pulled down by gravity. At a higher flow rate more area (between the float andthe

tube) is needed to accommodate the flow, so the float rises. Floats are made in many

differentshapes, with spheres and spherical ellipses being the most common. The float is shaped so

that it

rotates axially as the fluid passes. This allows you to tell if the float is stuck since it will

only rotate ifit is not.

For Digital measurements Flap system is used.

For Analog measurements we can use the following methods :

1. Flow meters

2. Venturimeters / Orifice meters


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3. Turbines

4. Mass flow meters ( oil level )

5. Ultrasonic Flow meters6. Magnetic Flow meter ( water level )

Selection of flow meter depends upon the purpose, accuracy and liquid to be measured sodifferent

types of meters used

.

TURBINE TYPE:

They are simplest of all. They work on the principle that on each rotation of the turbine apulse is

generated and that pulse is counted to get the flow rate.


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VENTURIMETERS :

Referring to the diagram, using Bernoulli's equation in the special case of incompressible

fluids (such as the approximation of a water jet), the theoretical pressure drop at the

constriction would be given by (./2)(v22 - v12).

And we know that rate of flow is given by:

Flow = k v (D.P)

Where DP is Differential Presure or the Pressure Drop.

CONTROL VALVES

A valve is a device that regulates the flow of substances (either gases, fluidized solids,slurries, or

liquids) by opening, closing, or partially obstructing various passageways. Valves are

technicallypipe fittings, but usually are discussed separately. Valves are used in a variety of

applications

including industrial, military, commercial, residential, transportation. Plumbing valves arethe most

obvious in everyday life, but many more are used.

Some valves are driven by pressure only, they are mainly used for safety purposes in steam

enginesand domestic heating or cooking appliances. Others are used in a controlled way, like in

Otto cycle

engines driven by a camshaft, where they play a major role in engine cycle control.


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Many valves are controlled manually with a handle attached to the valve stem. If the handle

is

turned a quarter of a full turn (90) between operating positions, the valve is called aquarter-turn

valve. Butterfly valves, ball valves, and plug valves are often quarter-turn valves. Valves

can also becontrolled by devices called actuators attached to the stem. They can be electromechanical

actuators such as an electric motor or solenoid, pneumatic actuators which are controlled

by airpressure, or hydraulic actuators which

are controlled by the pressure of a liquid such as oil or water. So there are basically three

types ofvalves that are used in power industries besides the handle valves.

They are :

PNEUMATIC VALVES They are air or gas controlled which is compressed to turn or

movethem

HYDRAULIC VALVES They utilize oil in place of Air as oil has better compression


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MOTORISED VALVES These valves are controlled by electric motors

FURNACE SAFEGUARD SUPERVISORY SYSTEM

FSSS is also called as Burner Management System (BMS). It is a microprocessor based

programmable logic controller of proven design incorporating all protection facilitiesrequired for

such system. Main objective of FSSS is to ensure safety of the boiler.

The 95 MW boilers are indirect type boilers. Fire takes place in front and in rear side.

Thats why its

called front and rear type boiler.

The 210 MW boilers are direct type boilers (which means that HSD is in direct contact

with coal)firing takes place from the corner. Thus it is also known as corner type boiler.

IGNITER SYSTEM

Igniter system is an automatic system, it takes the charge from 110kv and this spark isbrought in

front of the oil guns, which spray aerated HSD on the coal for coal combustion. There is a

5 minutedelay cycle before igniting, this is to evacuate or burn the HSD. This method is known as

PURGING.

PRESSURE SWITCH

Pressure switches are the devices that make or break a circuit. When pressure is applied,

the switch

under the switch gets pressed which is attached to a relay that makes or break the circuit.

Time delay can also be included in sensing the pressure with the help of pressure valves.


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Examples of pressure valves:

1. Manual valves (tap)

2. Motorized valves (actuator) works on motor action

3. Pneumatic valve (actuator) _ works due to pressure of compressed air

4. Hydraulic valve


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IT DEPARTMENT

. IT BTPS VISION

. IT ROLE & RESPONSIBLITIES @BTPS

. IT APPLICATION @BTPS

. BENEFITS OF IT INNOVATION @ BTPS

. VARIOUS E-SERVICES @BTPS

. SMS ALERT @ BTPS

. REWARDS & RECOGNITION


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BTPS IT VISION

. INTEGRATED IT ENABLEMENT OF BUSINESS PROCESSES FOR EFFICIENT

PLANT

MANAGEMENT. INFORMATION ANYTIME ANYWHERE

IT ROLE & RESPONSIBILITIES @ BTPS

1. Development, Implementation & Support for Local Applications

2. Procurement & Maintenance of IT Infrastructure ( PCs, Printers, Servers & Network

LAN,WAN

etc)

3. Support to users for ERP & modules to supplement ERP.

4. Customization & Implementation support for BTPS Applications to other projects.

IT APPLICATION @ BTPS

At BTPS, Information Technology has been used extensively to manage following business

processes-

1. Maintenance Management System

2. Materials Management System

3. Financial Accounting System4. Contracts Management System

5. Operations & ABT Monitoring System

6. Coal Monitoring & Accounting System7. Hospital Management System

8. HR, T/S & Training Management System

9. Office Automation & Communication System

10. E-Samadhan complaints monitoring system

Benefits of IT Innovations @ BTPS

1. OPERATIONS

Important & critical parameters of Power Plant operation are monitored online to enable

effective

control on operation of various equipments and reduce down time. Online load analysis &

Generation


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values are monitored to have optimum load balance of various units. Auxiliary power

consumption

monitored and controlled. Meritorial operation practicing enabled.

2. MAINTENANCE

Better control over maintenance cost by way of online information available through the

system.Based

on failure analysis and equipment history, modified maintenance strategy of Preventive,Predictive and

Risk Based maintenance is implemented. Equipment spares planning are streamlined by

way of Annual


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requirement, Vendor wise, linked to Equipment, Standardization of defects and repair

codes for easyfilling of Work Order Card, for future analysis.

3. MATERIALS

Material Planning and Procurement system streamlined, resulting in reduction in

Administrative leadTime. Further, procurement on Annual Rate Contract basis enabled through the system,

Ordering on

actual need basis (just in time). This further reduces lead time and Inventory carrying.

Detection of duplicate and obsolete items, standardization of material description and

specification,

Cleaning and Weeding of redundant data, resulting in overall system improvement and

functionalities,Availability of coal stock status online, reduction in demurrages paid to railways.

4. OFFICE AUTOMATION AND COMMUNICATION

With implementation of e-Desk/e-broadcast, e-alerts, auto mail and BTPS website,information is

available instantly to all and all time, resulting in tremendous reduction in paper

communication and

cost.

BTPS IT Applications Highlights

1. Single Login screen, Pass Word & Role based secured access .

2. G.U. Interface, Easy information retrieval/search facility.

3. Information captured once at source.4. Automation of routine activities.

A View of BTPS Login Page


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ERP/SAP MODULES IMPLEMENTED(ERP-ENTERPRISE RESOURCES PLANNING)

. Maintenance Management- PM

. Finance Management- FI

. Materials Management- MM

. Human Resource Management- HR

. Operations Management- OPN

. Employee Self Service- ESS

Maintenance Management system, Anurakshan @ BTPS

1. Permit to Work Issue with detailed feedback.

2. Daily Plant Meeting minutes generated online.3. Trends of defects priority wise /department wise for a period.

4. Equipment history with detailed feedback available.

5. Analysis of repeated equipment failure for corrective action.

6. Standardization of defects & repair codes.7. Interface with Materials Management System & CMS for WOC cost

MATERIAL & CONTRACT MANAGEMENT SYSTEM (CMS)

1. Initiation and approval of Contract Proposal.2. Preparation of Tender Documents and approvals.

3. Preparation and processing of Bills.

FINANANCIAL ACCOUNTING SYSTEM (FAS)

1. Status of Income Tax Details, PF slips, Leave, Accrued Interest, and Earning Cardavailable online.

2. Fund Flow Statements & other Reports for day to day functioning.

3. Bank Reconciliation.


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Coal Accounting System (CAS)

1. Online uploading of Wagon wise Weight from Wagon Tipplers.2. Coal and Rail Freight bill payments accounting & reconciliation.

3. Tariff Summary, coal accounting and MIS reports generated from the system.

HOSPITAL MANAGEMENT SYSTEM (HMS)

1. Online patient registration

2. Doctors prescription

3. Medicines issues/availability


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4. Investigation reports

5. Annual check-ups, patient history , referrals etc.

A View of Hospital Management System

HR/TRAINING MANAGEMENT SYSTEM

1. Computerized Attendance recording system.

2. Employee database to record/ update information of employees

3. Township/Quarter management system.

4. Performance Management analysis & evaluation system.


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E-SERVICES OFFICE

AUTOMATION &COMMUNICATIONKEY FOCUS AREATOWAREDS PAPERLESS

OFFICEE-Desk , E-Broadcast,

SMS & E-Mail as PrimaryCommunication &

Document Delivery

System.

A View of Tanning Management System

VARIOUS E-SERVICES @ BTPS

SMS ALERT @ BTPS

1. One more IT initiative for fast & convenient way to information sharing thru SMS2. Automatic SMS alert is already in use for plant load & unit Trip.

3. Send SMS instantly or scheduled date/time.

4. SMS to groups or individual numbers.


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Plant Load & Unit Trip SMS Alert

REWARDS & RECOGNITION

. Badarpur has achieved unique distinction of being; First site in NTPC, with independent

initiative of Development & Implementation of new Oracle based integrated online

Applications, with in house effort. This has been appreciated by NTPC higher

management.. BTPS Received Golden Peacock award for IT Innovation in 2004.

REFERENCE

. TRAINING REPORTS OF PAST YEARS AT NALANDA LIBRARY

. INTERNET

. DOCUMENTS OF IT DEPARTMENT


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