transformation project on energy saving and emission reduction … · 2016. 7. 13. · wet method...

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E1786 v5 Project Proposal for World Bank Global Environment Fund

ENVIRONMENTAL IMPACT SPECIFIC APPRAISAL

for

TRANSFORMATION PROJECT ON ENERGY SAVING AND EMISSION REDUCTION OF

YANGQUAN YANGGUANG POWER GENERATION COMPANY LTD. SHANXI

China Institute for Radiation Protection

November, 2007

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Project Name: Transformation Project on Energy Saving of Yangguang Power

Generation Company Ltd. Shanxi

Document Type: Environment Impact Specific Appraisal

Legal Representative of Appraisal Organization: Xuan Yiren

Contact person: Ma Hongyou

Contact Phone: (0351)2203007 Fax: (0351)2202377

Person in charge of the project: Ma Hongyou (Registered No. A13020110400)

Shi Xuefeng (ID No. of employment:L A13020095)

III

Persons in charge of each special issue for Environment Impact Specific Appraisal

Special issue Person in charge

Specialty Professional title

Qualification No.

Signature

Preface Shi Xuefeng

Environmental engineering

Assistant researcher

A13020095

Summary of existing project

Liu Hui Environmental planning and management

Deputy rearcher

A13020010500

Summary of Energy Saving and Reform Project

Shi Xuefeng


Assistant researche

A13020095

Summary of environment of regions effected by proposed project


Deputy rearcher

A13020010500

Analysis to environment impact of proposed project and policy for pollution protection

Zhang Jianxin


Senior engineer

A13020020400

Plan comparision and plan determination

Shi Xuefeng


Assistant researche

A13020095

Management plan for environment

Zhang Jianxin


Senior engineer

A13020020400

Public participation


Deputy rearcher

A13020010500

Conclusion Shi Xuefeng


Assistant researche

A13020095

Ma Hongyou

Environmental science

Deputy rearcher

A13020110400General editors of the report Zhang

Jianxin Environmental engineering

Senior engineer

A13020020400

IV

Contents

1 Preface

1.1 Project background and task origin······················································1

1.2 Appraisal goals ····················································································3

1.3 Basis of compiling ···············································································3

1.4 Identification of key environment issues and the factors of environment

impact··································································································5

1.5 Appraisal focus····················································································8

1.6 Appraisal grade····················································································9

1.7 Appraisal criteria ·················································································9

1.8 Environment sensitive area and protection targets ····························12

1.9 Security and ensure policies of WB ···················································13

2 Summary of project and engineering analysis

2.1 Summary of existing project ······························································14

2.2 Project analysis of transformation on energy sving····························25

3 Environmental situation of area affected by proposed project

3.1 Summary of natural environment·······················································48

3.2 Summary of social environment ························································50

3.3 Summary of ecological environment ·················································52

3.4 Living quality ····················································································52

3.5 Current situation of environmental quality·········································52

4 Analysis to environmental impacts of proposed project and

countermeasure to prevent and control the pollution

4.1 Analysis to environmental impact in implementation period ·············58

4.2 Analysis to environmental impact in operation period ·······················61

4.3 Analysis to social and environmental impact ·····································62

V

4.4 Analysis to positive environmental impacts of energy saving and

emission reduction···········································································63

5 Comparison and selection of plans

5.1 Analysis of zero option······································································65

5.2 Comparison and selection of optional plans·······································67

6 Environmental management and monitoring plan

6.1 Key impacts to environment and measure to reduce them··················61

6.2 Environmental management plan·······················································73

6.3 Environmental monitoring plan ·························································88

7 Public participation

7.1Goals of public participation·······························································92

7.2 Way of public participation ·······························································92

7.3 The 1st time public participation ························································93

7.4 The 2nd time public participation························································97

7.5 Exposure of information ····································································98

7.6 Brief summary·················································································100

8 Conclusion and suggestions

8.1 Conclusion·······················································································100

8.2 Suggestions······················································································106

Appendix Calculation formula for energy saving and emission reduction

Appendix “Letter of Authorization for Environment Impact Appraisal on the Transformation Project of Energy Saving for Yangguang Power Generation Company Ltd. Shanxi”

1

Environmental Impact Report on Transformation of Energy Saving and Emission Reduction for

Shanxi Yangguang Power Generaration Company Ltd.


1 Preface 1.1 Project background and task origin

Located in the boundary of Pingding County, Yangquan City, Shanxi Province, Shanxi Yangguang Power Generation Company Ltd. (Hereinafter refers as Yangguang Power Plant) is 4km away from the county seat and 15km to Yangquan City with an easy access for transportation, and the Expressway from Taiyuan to Shijiazhuang is at the north of the company. The plant covers an area of about 39 hectre and there are 1542 staff in the company.

With a total installed capacity of 4×300MW condensing coal-burning steam

turbine and a boilter total evaporating capacity of 4100t/h, Yangguang Power Plant is a national key construction project. Since the beginning of preparation for construction in 1984, the construction of plant was begun on December 1993 and 4 generator sets began to generate power from December 1996 to November 1999 successively.

According to the requirements of the relative policies, Yangguang Power Plant

has made transformation to the existing 4 generator sets by using Limestone-Gypsum Wet Method Desulfurization Technology (using limestone-gypsum method) and the desulfurization efficiency is 90% and the plant has also implemented the transformation of dust catcher at the same time. At present, the transformation of desulfurization for 4 boilers has been finished and all put into operation. The electrostatic precipitators from No.2 and No.4 boiler have been transformed into bag filters and put into use and the dust collection rate has been increased from former 99% into current 99.9%. The control system of electrostatic precipitators of No.1 and 3 boilers has been upgraded and transformed. Through the transformation of precipitators and desulfurization system, the soot and SO2 emissions from the plant will be greately reduced to lighten the impact to local environment.

The state government has paid very special attention to the energy saving and

emission reduction and state Development and Reform Commission issued “the Notice on the Publication and Issue on Mid-Term and Long-Term Special Planing of Energy Saving” in 2004, requiring that the transformation of thermal power plants should be regarded as the key field and key project, the coal consumption of thermal power plants in 2010 should meet the target of 360g standard coal/kwh, and in 2020 the target of 320g standard coal/kwh. On May 23, this year, the State Council issued “A Notice on Comprehensive Operation Plan for Energy Saving and Emission Reduction”, illustrating that the current situation is very serious to realize the target of energy saving and emission reduction and putting forward various kinds of operation

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plans for the implementation of energy saving and emission reduction to form the energy saving capacity of 240 million tons of standard coal during the period of “11th Five-Year Plan” and the capacity of 50 million tons of standard coal in this year. It also said that 10 key energy saving projects as the transformation project of industrial boiler (kiln), regional cogeneration engineering project, the project of waste heat and excess pressure utilization, the project of oil saving and oil substitutation, energy saving project of motor system, optimization project of energy system, energy saving project of building, green lighting project, energy saving project of governmental organization, the project of monitoring for energy saving and technical service system construction are the key points to be implemented and among those the thermal power plants are the most important area to be transformed.

In recent years, Yangguang Power Plant has also responded to the national policy

on energy saving and emission reduction, paying the most important attention to the work of energy saving and emission reduction and activitely applying the new technology and process on energy saving to try its best to reduce the energy consumption of the plant. For an example, the plant has implemented transformation of frequency conversion energy saving to circulation pump, condensing pump and fuel pump successively to farthest save the power consumption and to air pre-heaters from No.1 and No.2 boilers to save coal consumption, resulting in a favorable benefit on energy saving.

As the completion of transformation and putting into operation of desulfurization

system and precipitators of Yangguang Power Plant and as the increase of power consumption of running equipment, the power utilization rate will increase about 1.5% and coal consumption about 3-4g/kwh and bring some impact on the economic operation for the power plant. To farthest overcome the side impact caused by these factors to the economic operation of the plant, it should enlarge the investment to the projects of energy saving to reduce the energy consumption as much as possible.

The transformation project on energy saving of Yangguang Power Plant includes

four sub-projects: The transformation project of frequency conversion of primary fan from No.1 boiler, Online Monitoring Equipment Project for coal powder pipe on No.4 boiler, the transformation project of steam seal for No.4 boiler and the software development project of inverse balancing for coal consumption calculation of the whole plant. After the implementation of these projects, every year the plant can save

18,760 tons of standard coal, the reduction volumes of producing soot, SO2 NO and

CO2 will be 6922t/a, 732t/, 170t/a and 49939t/a and the emission reduction volumes of soot, SO2, NOX and CO2 will be 6.9t/a, 73.2t/a, 170t/a and 49939t/a. The total investment of the project is 14.22 million yuan which will be submitted to World Bank for the financing from Global Environment Fund.

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The project should process environment impact appraisal according to the regulations from “Environment Impact Appraisal Law of PRC” and “World Bank Operation Guidebook-Environment Impact Appraisal”. Yangguang Power Generation Company Ltd. of Shanxi Province entrusted China Academy of Radiation Protection on August 1st, 2007 to be in charge of the environment impact appraisal for the transformation project of energy saving.

1.2 Appraisal goals

The environment impact appraisan of this project has made analysis to the technical standard, index of energy saving, economic index and investment and operation cost through the combination with the engineering characteristic of the transformation of energy saving project and the comparison of the alternative plans to finally determine the selected plan. A complete and systematic analysis has been made to the positive and negative impacts caused by the project during the implementation period and operation period to local environment and social environment and the feasibility of the construction of the project has been conducted from the point of environmental protection. The management plan of environment protection and environment monitoring plan of the project are confirmed through the integration of suggestions from public participation.

1.3 Basis of compiling

1.3.1 Basis of task Yangguang Power Generation Company Ltd. Shanxi, “Letter of Authorization for Environment Impact Appraisal on the Transformation Project of Energy Saving for Yangguang Power Generation Company Ltd. Shanxi” (See appendix) August 1st,2007.

1.3.2 Basis of laws, regulation and policies

(1) Environment Protection Laws of PRC December 1989.

(2) Air Pollution Prevention and Control Laws of PR Revised on

Aprin, 2000.

(3) Detailed Rules of Implementation for Water Pollution Prevention and

Control of PRC Revised on March 2000.

(4) Environment Noise Pollution Protection and Control Laws of

4




PRC December, 1996.

(5) Solid Waste Pollution Protection and Control Laws of PRCRevised

on December, 2004.

(6) Environment Impact Appraisal Laws of PRC October, 2002.

(7) Promotion Laws on Clean Production of PRC June, 2002.

(8) The Order of State Council of PRC No. 253Regulations on

Environment Protection and Management for Construction

Project November, 1998.

(9) The Order of State Environment Protection Bureau No. 14The List for

Classification Management of Environment Protection for Construction

Project January, 2003.

(10) The Order of State Development and Reform Commission of PRC

No.40 Directory of Guiding the Industrial Structure Reasjustment(2005

Version) December, 2005.

(11) Huanfa No. [2006]28, State Environment Protection

Bureau Temporary Measure on Public Participation of Environment Impact

Appraisal March, 2006.

(12) Huanjian No. [1993]324, State Environment Protection BureauNotice

on Strengthening the Management of Environment Impact Appraisal for

Construction Project Financed by International Fund OrganizationJune

21th, 1993. (13) Fagaihuanzi No. [2004]2505 by State Development and Reform

Commission Notice on Publication and Issue of Mid-Term and Long-Term

Special Planning for Energy Saving November 25, 2004.

(14) Guofa No. [2005]39 by State CouncilDecision on Carrying out

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Scientific Outlook of Development and Strengthening Environment

Protection 2005.

(15) Guofa No. [2006]28 by State CouncilDecision on Strengthening

Energy Saving August 6, 2006.

(16) Guofa No. [2007]15 by State CouncilNotice on the Publication and

Issue of Integrated Operation Plan for Energy Saving and Emission

Reduction May, 23, 2007.

1.3.3 Related Regulations from World Bank

� World Bank OP/BP4.01 and AnnexEIA January, 1999.

� World Bank OP/ EIA January, 1999.

� World Bank GP4.01 EIA January, 1999.

� World Bank OP/BP4.04 Natural Habitated Land September, 1995.

� World Bank GP4.07 Management of Water Resource December,

2000.

(6) World Bank GP14.70 Participation of NGO in WB Financed

Activities

1.3.4 Guiding rule and technical criteria for appraisal technology

(1) General Rule, Guiding rule for EIA Techonology HJ/T2.1-93

(2) Air Environment, Guiding rule for EIA Techonology HJ/T2.2-93

(3) Surface Water Environment, Guiding rule for EIA

Techonology HJ/T2.3-93

(4) Sound Environment, Guiding rule for EIA Techonology HJ/T2.4-

1995

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1.3.5 Data for Engineering Design

(1) Technical Plan for Transformation Project of Energy Saving for

Yangguang Power Generation Company Ltd. ShanxiYangguang Power

Generation Company Ltd. Shanxi, July, 2007.

(2) Related technical data provided by the construction unit, AugustOctober,

2007.

1.4 Identification of key environment issues and the factors of environment impact

1.4.1 Identification of key environment issues Idintification of key environment issues of the project has been made according

to the characteristic of the project and combining with the environmental characteristic of the local area. The results are shown in Table 1.4-1.

Table 1.4-1 Results of indentification of key environment issues

Period Pollution type Project Environmental issue

The transformation project of frequency conversion of primary fan from No.1 boiler,

Production of small amount of dust during the process of the construction of frequency conversion control room

Online Monitoring Equipment Project for coal powder pipe on No.4 boiler

Production of small amount of soot produced from welding during the process of equipment installation

Transformation project of steam seal for No.4 boiler

Production of a small amount of soot produced from welding during the process of transformation

Waste gas

Software development project of inverse balancing for coal consumption calculation of the whole plant

Production of a small amount of soot produced from welding during the process of equipment installation


Production of a small amount of waste water from the construction process of 4 frequency conversion control rooms.


No

Imple- mentation

period

Waste water

Transformation project of steam seal for No.4 boiler No

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No


Production of 60 70dB(A) noise during the process of construction of frequency conversion control room


Production of 50 60dB(A) noise during the transformation process


Production of 60 70dB(A) noise during the transformation process

Noise


Production of 50 60dB(A) noise during the measurement equipment installation


Production of a small amount of construction waste during the construction of frequency conversion control room


No


78 waste steam seal rings from the replacement of steam seal in transformation

Solid waste


No

Waste gas

4 Sub-projects No

Waste water

4 Sub-projects No


Production of 50 60dB(A) noise from axial flow fan functioning for cooling in frequency conversion


No

Operation period

Noise


Noise from vibration of steam seal

8





No.

Solid waste

4 Sub-projects No.

1.4.2 The indentification and selection of factors affecting environment The matrix method has been used to identify and select the factors affecting the

environment of the project according to the characteristic of project and the identification results of key environment issue, the results can ben seen in Table 1.4-2

Table 1.4-2 The indentification and selection of factors affecting environment

Implimentation period Operation period

Project

Environ- Mental factors



Transformation

project of steam seal for No.4 boiler

Software development project of inverse balancing for coal

consumption

calculation of the whole plant




Software development

project of inverse

balancing for coal

consumption calculation of

the whole plant

Environ

ment air -1S -1S -1S -1S +1L +1L +1L +1L

Surface

water

Natural

physical

environ

ment Sound

environ

ment

-1S -1S -1S -1S

Agro-

crops +1L +1L +1L +1L

Natural

ecologic

al

environ

ment

Plants

on

ground

+1L +1L +1L +1L

Enterpris

e’s profit +1L +1L +1L +1L

Social

environ

ment Public

health +1L +1L +1L +1L

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Newly

added

land

N N N N N N N N

Resettle

ment N N N N N N N N

Note “ ”means positive impact “ ” means negative impact “N” means no impact. “1” minor impact “2” medium impact “3” major impact. “S” short-term impact “L” long-term impact.

1.5 Appraisal focus

According to the engineering characteristic of the transformation project of energy saving and combining the environment issues with the indentification and selection result of the factors affecting environment, the appraisal focus of the project is to make a quantitive analysis for the energy saving index after the transformation project, the improvement of local environmental quality from the reduction of pollutant emission and the positive benefit from energy saving and emission reduction.

1.6 Appraisal grade

The side impact caused from the transformation project of energy saving to the environment is very limited, and it will bring certain function of improvement to local environment after the completion of transformation project since the project will bring agood impact of energy saving and emission reduction for the plant.

According to the principle of classification of OP4.01 EIA of World Bank, this project belongs to a project only concerning refitting, maintenance and upgrading. It is not necessary to process a full-scale environment impact appraisal, but still necessary to process environmental analysis. Therefore, this project belongs to B category of environment.

1.7 Appraisal criteria

According to the requirement of zone planning for environmental function of the appraisal area, the criteris for the appraisal of the project are:

1.7.1 Criteria for environmental quality (1) Criteria for environmental air quality: the area the project is located is the

mixture area of rural and general industrial zones, the environmental air quality function zone planning belongs to second zone, where the second grade of

Standards of environmental aie quality GB3095-1996 should be carried out.

The standard limits are shown in Table 1.7-1.

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Table 1.7-1 Concentration limited values for environmental air quality

standard mg/m3

Pollutants TSP SO2 NO2 PM10 Annual average 0.20 0.06 0.08 0.10 Daily average 0.30 0.15 0.12 0.15 1 houraverage — 0.50 0.24 —

(2) Surface water: The surface water system located near the project belongs to Nanchuan River which belongs to Ziyahe water system of Hai River drainage basin and the surface water appraisal should use IV category standard from

GB3838 2002 of Standard for surface wter environmental quality and the

standard limited values are shown in Table 1.7-2.

Table 1.7-2 Standard limited values of surface water environmental

quality mg/L

Pollutant pH Ammonia-

nitrogen CODCr BOD5

Volatile

phenol

Standard

value 6 9 1.5 30 6 0.01

Pollutant Cyanide Fluoride Sulfide Oil

Standard

value 0.2 1.5 0.5 0.5

Note pH dimensionless (3) Underground water: Local people living in this area use the underground

water for drinking. According to the underground water classification requirement of

Standard for underground water quality GB/T14848-93 and the underground

waer defined as category III based on “the basic value of people healthcare, mainly used for water source for collective living and drinking and agriculture”, the quality of underground water in the appraisal zone is defined as category III and applied to

standard of category III from Standard for underground water

quality GB/T14848-93 . The standard limited values are shown in Table 1.7-3.

Table 1.7-3 Standard limited values of underground water environmental

quality mg/L

Project pH value Total rigidity

(CaCO3)Sulfate Fluoride

Total caliform group(N/L)

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Standard value

6.5 8.5 �450 �250 �1.0 �3.0

Project Ammonia-

nitrogen Nitrate Nitrite Cr6

Total bacteria (N/ml)

Standard value

�0.2 �20 �0.02 �0.05 �100

(4) Environment noise: Apply to 2 category standard from Standard for

environmental noise in urban area(GB3096-93), the standard value is listed in

Table 1.7-4.

Table 1.7-4 Standard for environmental noise

Standard value (dB(A)) Category

Day Night 2 60 50

1.7.2 Standard for Pollutant Emission

� Implementation period The noise at construction site applies to the requirement of limited values for

construction site from Noise limited value for construction site(GB12523-90)

and the standard values are shown in Table 1.7-5.

Table 1.7-5 Limited value for noise from construction site

Limited value of noise

(dB(A)) Implementation

period Main noise source

Day Night

Structure Tamper, electronic saw etc. 70 55

Decoration Crane and lift 65 55

�Implementation period �Standard for air pollutant emission

According to the requirements of Shanxi Provincial Environmental Protection Bureau to the Approval of EIA on desulfurization project of Yangguang Power Plant, the desulfurizaation project before the transformation should carry out the highest allowable emission concentration for the phase I of coal-burning boiler regulated in

Standard for air pollutant emission for thermal power plantGB13223-

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2003 and after the transformation it should follow the highest allowable emission

concentration for the phase III of the standard. The standard values are shown in Table 1.7-6.

Table 1.7-6 Standard for air pollutant emission for thermal power plant

Boiler type

Pollutants Highest allowable emission concentration of Phase I mg/m3

Highest allowable emission concentration of Phase

III mg/m3

Soot 600 50 SO2 2100 400

Coal burning boiler NOX 1500 —

Note Vdaf 10%

� Standrd for waste water emission

Waste water emission should carry out the first grade standard from Table 4 of

Standard for waste water emission GB8978 1996 . The standard values are

shown in Table 1.7-7.

Table 1.7-7 Standard for waste water emission

Pollutant Standard

value Pollutant

Standard value

Pollutant Standard

value PH 6 9 Oil 5 CODCr 100

Suspended solid

70 Fluoride 10

� Standard for noise emission

The standard for noise emission in the west, south and east boundary of the plant

should carry out the standard of Category II from Standard for noise from industrial

plant boundary GB12348 90 and the north boundary the standard of Category

IV from GB12348 – 90. The standard limited values are shown in Table 1.7-8.

Table .7-8 Noise standard for industrial plant boundary

Standard value B(A)) Category

Day Night

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� 60 50� 70 55

�Standard for solid waste storage

The treatment of solid waste should carry “the Control standard of the storage of general industrial solid waste and treatment of site pollution” (GB18599 – 2001).

1.8 Environmental sensitive area and protection target.

Table 1.8-1 shows the environmental protection targets and sensitive area around the power plant.

Table 1.8-1 Environmental protection targets

Environmental factors

Environmental sensitive area

and protection targets

Characteristic of area

Direction Distance

(km)

Xiaonanao Village village E 0.26 Guanzhuan Village village W 1.44

Changjiaguo Village E 1.18 Atmosphere

Nanao Village village N 0.81

water Nanchuan River Category IV N 0.15

Noise Xiaonano Village village E 0.26

1.9 Security and ensure policy of World Bank

According to the relative regulations of World Bank, it is necessary to pay special attention to public benefit during the process of project implementation and it is also the goal EIA is being carried out by the appraisal unit. Therefore, the unit in charge of the appraisal has verified and confirmed the policies of World Bank on security and ensure one by one according to the related regulations. The results are shown in Table 1.9-1.

Table 1.9-1 The filtration of security and ensure policies

Series No.

Content for checking

Confirmation result

1EIA

OP/BP4.01EIA is under processing

2Natural habitated

land The transformation of energy saving is implemented in

the existing area of the plant which is located near the

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OP/BP4.04 county seat of Pingding, Yangquan City, Shanxi Province, not concerning with natural habitated land.

3Management of

pests OP4.09

The project has not involved in management of pests.

4Material cultural

heratige OP/BP4.11

The project is implemented in the plant to make transformation on energy saving. Through the field survey by the unit in charge of EIA, confirmation is made that there is no any material and cultural heratiges in this project.

5Non-volunteer resettlement OP/BP4.12

The project has not involved in the issue of resettlement.

6Minority

OP/BP4.11

The area of the project is the place of assembling for Han nationality and not involving with the issue of

minority.

7Forest

OP/BP4.36No natural forest or artificial forest located near the

project.

8Dam security OP/BP4.37

No large scale dam near the project.

9Region of disputation OP/BP7.60

No international region of disputation at the project area.

10 International river

OP/BP7.50The project has not involved in international rivers.

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2 Summary of project and engineering analysis

2.1 Summary of the existing project

2.1.1 Geographical location

Located in the boundary of Pingding County, Yangquan City, Shanxi Province, Yangguang Power Plant is 15km away from Yangquan City and 4km to county seat of Pingding County. The topography where the plant is located is widen, in the opposite bank with Nanao Xiang acrossing Nanchuan River and Yang-She Railway Line connecting with Shijiazhuan-Taiyuan Railway is passing through the east of the plant area. Special railway line of Yangquan No.5 Coalmine Bureau passing through the north of the plant connects with Yang-She Railway Line at Pingding. Yang-Xi highway passes through in the east side of the plant while Shijiazhuan-Taiyuan Expressway passes in the north of the plant, providing a good access of transportation. Yangpoguo ash field of the plant is a wet ash field locating at about 7km to the east of the plant. The slag yard of the power plant is No.3 gouge in the south of the plant. The geographical locations of the plant site, ash field and slag yard can be found in the Figure 2.1-1.

2.1.2 Summary of project

The total installed capacity of Yangguang Power Generation Company Ltd. is 4×300MW condensing coal-burning steam turbine and a boilter total evaporating capacity of 4100t/h. Began to prepare the construction in 1984 and the construction was begun on December 1993 and 4 generator groups began to put into operation on November 27, 1999. No. 1, 2, 3 and 4 boilers share a steel bar concrete stack with a mouth diameter of 8m and a height of 240m.

According to the requirements of State Environmental Protection Bureau, People’s Government of Shanxi Province and Municipal Government of Yangquan City, Yangguang Power Plant has conducted the transformation of disulfurization to 4 generator groups using Limestone-Gypsum Wet Method Desulfurization Technology and the desulfurization efficiency is 90% and transformed the former electrostatic precipitators. At present, the desulfurization project of 4 generator groups have already completed and put into operation. On December, 2006, the electrostatic precipitators associated with No.2 and 4 boilers have been transformed into Bag filters and the precipitator rate has been increased from former 99% to 99.9% while the control system of electrostatic precipitators of No.1 and 3 boilers have been upgraded and transformed.

16




Figure 2.1-1 Geographical locations of plant site, ash field and slag yard of Yangguang Power Plant

N

6ODJ

3ODQW

$VK

17




Ash moving system utilizes high concentrated hydraulic transportation with a ratio of 1: 4 for ash and water, being transported to Yangpoguo Ash Field through two steps of ash mortar pumps. To realize an integrated utilization of power coal ash, the dry ash intake systems had been added to No.2, 3 and 4 boilers from 2005 to 2006 and the slag is transported by truck to slag yard for storage.

The key facilities and environmental protection equipment of Yangguang Power Plant are shown in Table 2.1-1.

Table 2.1-1 A table of summary of key facilities and environmental protection

equipment of Yangguang Power Plant

Project Unit 1# 2# 3# 4#

Contribution MW 300 300 300 300 Contribution and time to put into operation

Time Each group began to put into operation from

December 1996 to November 1999 every year.

Model

DG1025/18.2-II“W”blaze,

positive pressure direct

blowing, subcritical, one

mediate reheat, natural

circulation boilers.

B&WB-1025/18.3M“W”

blaze, intermediate bunker,

subcritical, one mediate

reheat, natural circulation

steam boilers.

Boiler

Vaporization volume

t/h 1025 1025 1025 1025

Model N300-16.7/537/537-4

Variety Subcritical, single shaft double cylinders, two

condensers, one mediate reheat section condenser Steam turbine

Contribution MW 300 300 300 300 Model QFSN-300-2-20

Cooling mode

Water—hydrogen—hydrogen Generator

Capacity MW 300 300 300 300 Varitey Limestone-Gypsum Wet Method Desulfurization

Desulfurization equipment

Desulfurization rate

% 90

Variety

Double chamber 4

electronic fields

electrostatic

precipitater

(Control system

has been upgraded

and reformed

Bag filter

Double chamber 4

electronic fields

electrostatic

precipitater

(Control system has

been upgraded and

reformed

Bag filter

Precipitators

Dust catching rate

% 99.0 99.9 99.0 99.9Flu

ega

str

eatm

ente

quip

men

t

Stack Series No. 1# 2#

18




Mode Reinforced concrete

structure Reinforced concrete

structure Height m 240 240 Mouth

diameter m 8 8

Variety Adopting natural ventilation cooling tower Coolind mode Cooling

space m3 4500 4500 4500 4500

Waste water from

production

Waste water after treatment of waster water treatment

station recycles back to coal transportation system,

spraying in coal field or supplies to ash washing system

Domestic sewage

After 2-grade bio-chemical treatment it will supply into

ash washing system

Way of waste water treatment

Ash water After clarification of silo, it will be emitted out

Powder coal ash

High concentration water ash emission will put into ash

field or be used together with coal powder for

comprehensive usage. Way of slad treatment

Slag Slag will be transported by trucks to slag yard or

comprehensive usage.

2.1.3 Layout of plant area

In the plant area, 220kv indoor distribution device, natural ventilization cooling tower, major workshop, railway line and coal field are allocated from south to north. The indoor distribution device is located at the terrace in the farmost south of the plant area, linking with the power line outside the plant at the south. The dateiled layout is shown in Figure 2.1-2.

2.1.4 Coal consumption and water consumption

(1) Coal consumption The coal used by the plant is supplied by local coalmiles under the administration

of Yangquan No. 5 Coalmine and Pingding County among which all the coal supplied by Yangquan No.5 Coalmine is transported into the plant through railway and those by Pingding local coalmine is transported by truck, entering from the east side of the plant.

Anthracite quality burned by Yangguang Power Plant in 2005-2006 is: sulfur 0.68-1.8%, ash content 18075-45.02%, the average quality of coal is shown in Table 2.1-2. The total coal burning volume is 3.8358 million t/a.

19




Table 2.1-2 Analysis of average coal quality in 2005-2006

Project Symbol Unit Numerical value Applied base moisture Mt % 9.6 Received base ash content Aar % 30.24 Dried base volatile Vdaf % 7.5 Received base carbon Car % 59.12 Received base sulfur St,ar % 1.66 Received base hydrogen Har % 2.39 Received base nitrogen Nar % 0.86 Received base oxygen Oar % 3.47 Reived base low calorific value Qnet.ar kJ/kg 22180

(2) Water consumption The water needed for the project is supplied by Water Pumping Project from Nianziguang to Pingding with a fresh water volume of 3092m3/h. Table 2.1-3 shows the water consumption situation of the plant and Figure 2.1-3 shows water balancing of the power plant.

20




1

23

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

No Name No Name No Name1 Turbinehouse 12 In house220kv power

distribution facility23 Hydrogen generation

station2 Deoxygenating

house13 Natural shaft cooling

tower24 Officebuilding

3 Coal bunker 14 Signal tower 25 Communicationbuilding

4 Boiler house 15 Underground bridgeandtruck dischargeditch

26 Open oil storage

5 Precipitators 16 Coal yard 27 Dinning hall6 Wind-blower

house17 Coal transport building 28 Single resident building

7 Flue channel 18 Ash pumpshouse 29 Shelter storage8 Chimney 19 Fuel tanks 30 Material warehouse9 Boiler imitation

house20 Acid and base storage 31 Coal dozer house

10 Central controlbuilding

21 Chemical water treatmenthouse

32 Wastewater treatmentplant

11 Transformers 22 Air compressor house 33 Coal Handling Gallery34 Desulfuration tower

34

Locations of transformation projects on energy saving

Symbol Transformation Project

Transformation of frequency conversion for primary fan on No.1 boiler

Transformation of steam seal on No.4 generator group

� Installation of onlinemonitoring on coal ash pipe lineof No. 4 boiler

21




Figure 2.1-2 Layout of Plant Area

22


Table 2.1-3 Situation of water using by power plant

Variety of water source

Purpose Unit Volume of circulation

water

Volume of supplied fresh

water Cooling water 74000 1579 Supplied water

for boiler 194

Industrial water

m3/h

1303

Ground water

Domestic water m3/h 16 Total m3/h 74000 3092

Cooling towerCirculation water

74000

Circulation Water

Water for chemical treatment

Water source

Water recovery pool

Neutralization pool

Evaporation loss

Ash flushing pool

3092

15791036

1303

194112

82

16

38

13

6203

79

1

Desulfuration system

268

298

1005Water for

industrial use

Industrial Wastewater Treatment Plant

288

20

235

Coal transport system, coal yard spray

20

Ash Yard

Wastewater discharge 543

Boiler refill

Water for domestic use

Biochemical Treatment

Watering plants or

street spray 4loss

Figure 2.1-3 Water balancing chart of plant

Waste water produced from the plant and domestic waste water from the plant area enter the two systems for production waste water treatment and domestic waster treatment separately and after the treatment they are sent back to use in coal transportation system, spraying in coal field and water for ash pouring, the drainage outside ash field is used to emit the water into Nangchuan River.

2.1.5 Situation of pollutant emission

(1) Waste gas

� Concentration of emission The Testing Center of Taiyuan University of Technology conducted monitorings

Table2.1-4 for flue gas from boiler in power plant on July 2004 and April 2005

respectively. The result shows that the concentrations of soot and NOx emission from 4 boilers all meet the requirements of the I Period of “the Standard of Air Pullutant Emission of Thermal Power Plant”(GB13223-2003). Since the power plant had not

23


realized desulfurization project when monitoring, the concentration of SO2 emission from flue gas of boiler exceeds the standard at that time.

In 2006, after the completion of transformation of bag filters associated with No2 and 3 boilers, Haarbin University of Technology, Sciene and Technology for Environment Protection Company Ltd., conducted a test to the capacity of the equipment and the result was: the soot concentration in the flue gas at the exit of the bag filters was 18.75mg/m3 after the transformation; the soot concentration in the flue gas at the exit of the electrostatic precipitator of No.1 and 3 boilers after the transformation was 35.0mg/m3: . Afte the full operation of desulfurization equipment, the desulfurization rate of soot from boilers was 90%.

After the transformation of desulfurization and precipitators, the soot and S02 emissions of No. 1 and 4 blioers meet the requirements of III time period standard from “the standard of pollutant emissions from thermal power plant” (GB13223-2003). From the bellow Table 2.1-4, we can find the concentration of pollutants before the transformation of desulfurizationa and precipitators and the conditions of meeting the standard.

Table 2.1-4 Flue gas and pollutant emission situation from boiler unit:mg/m3

Pollutant 1# 2# 3# 4# Emission concentration 358.4 414.6 234.2 276.6

Emission standard 600 600 600 600 Soot

Meeting standard or not

Meeting standard

Meeting standard

Meeting standard

Meeting standard

Emission concentration 3345 3167 3147 2642

Emission standard 2100 2100 2100 2100 SO2


Exceeding standard

Exceeding standard

Exceeding standard

Exceeding standard

Emission concentration —— —— 1344.80 1109.97

Emission standard 1500 1500 1500 1500

Bef

ore

tran

sfor

mat

ion

ofdu

stca

tchi

ngan

dde

sulf

uriz

atio

n

NOx

Meeting standard or not —— ——

Meeting standard

Meeting standard

Emission concentration 18.75 35.0 18.75 35.0

Emission standard 50 50 50 50 Soot


Meeting standard

Meeting standard

Meeting standard

Meeting standard

Emission concentration 334.5 316.7 314.7 264.2

Aft

ertr

ansf

orm

atio

nof

dust

catc

hing

and

desu

lfur

izat

ion

SO2

Emission standard 400 400 400 400

24



Meeting standard

Meeting standard

Meeting standard

Meeting standard

Note No monitoring is conducted to NOx from 1#2# boilers.

� Emission volume According to the statistic report of environment of Yangguang Power Plant in

2006, the pollutant emission of the plant was : SO2 36668t/a; soot 6060t/a; the total SO2 volume index assigned by Yangquan Environmental Protection Bureau was 52530 t/a, meeting the requirement of the total volume index. After the completion of transformation of desulfurization and precipitators, the total volume index of SO2 designated by Yangquan Environmental Protection Bureau was 6500 t/a.

(2) Waste water The waste water emitted to outside in the Thermal Power Plant is only the waste

water emission in ash field. Table 2.1-5 shows the results of monitoring conducted by Shanxi Electronic Science Research Institute on waste water emission emitted to outside of ash field meeting the requirements of the Grade One standard from “Standards of Conprehensive Emission of Waste Water” (GB8978-1996), and emitting into Nanchuan River from the sewage of ash field.

Table 2.1-5 Ash water quality emitted outside the ash field (unit:mg/L except

pH)

Project pH Suspended

solid Fluoride CODCr oil

Ash water quality

7.84 11.4 1.47 25.3 Not found

Standard value

6~9 70 10 100 10

(3) Solid waste

The major solid wastes are coal powder and slag. The production of coal powder is about 962,000 t/a, the production of slad is 118,000 t/a. The coal powder uses high concentration water power ash washing system and transported to Yangpogou ash field through two steps ash mortar pump systems. To implemente a comprehensive utilization of coal powder, the dry ash conveying systems were added to No.2, 3 and 4 boliers in 2005-2006 and it is estimated that in 2007 the comprehensive utilization volume of coal powder will reach 240,000 tons with a utilization rate of 24.5%. The waste slad is transported by trucks to the consumers of comprehensive utilization or to store them in No.3 slag yard located in the south of the plant.

2.1.6 The existing issues and the measures taken

25


As an old plant put into operation from 1996-1999 successively, Yangguang Power Plant has carried out the transformation and improved the impmentation of prevention and control on pollution continuously according to the more and more strick control on the environmental protection during its development, such as: the transformation of precipitators, the transformation of desulfurization, transformation of dry ash conveying system and wind-proof wall in coal field, greatly reducing the emission volume of pollutants and making a great contribution to the local environment.

After a series of transformation measures, the measures which can still be further improved for the pollution protection and control are as follows:

Desulfurization of flue gas: the boilers the power plant are using are “W”

type blaze with a high temperature in furnace chamber and large emission of NOX. Though this emission is in accordance with the standard of “Air Pollutants Emission” (GB13223-2003) Time period of I, the power plant should still carry out further measures to reduce the emission of NOX for the improvement of local environment.

Solution: The power plant should set up an independent project bureau on denitrogenation environmental protection and equipped with special personnel to be in charge of the data collection of data and preliminary study for this work.

To further increase the conprehensive utilization rate of coal powder

At present, there is still a great volume of coal powder and stag which have not been utilized completely.

Solution: To increase the comprehensive utilization rate of coal powder, the measures the plant is going to carry out include: installation of day ash catching system to No. 1 boiler, construction of the production line of gas-adding concrete block, further development of market for coal powder to raise the comprehensive utilization rate of coal powder to more than 75%.

2.2 Analysis to engineering of transformation project on energy

saving

2.2.1 Situation of energy consumption of Yangguang Power Plant The annual energy consumption of Yangguang Power Plant is about 2.9 million

tons, the level of coal comsumption for power supply is about 348g/kwh level, the annual fresh water volume is about 20 million tons and energy consumed by the plant itself is about 300 to 400 million digrees.

In recent years, the energy saving project has been listed as the first option for the technical transformation project and realized many energy saving projects as the transformation of frequency conversion and the transformation of air preheaters. The energy consumption of each generator group is reducing year by year, the detailed index can be found in Table 2.2-1.

26


Table 2.2-1 Situation of energy consumption of Yangguang Power Plant

Time Project

2003 2004 2005 2006

Power generated 10

thousand kwh793618 843168 820668 822988

Coal consumption for

power supply g/kwh

350 349 349 348

Power utilization rate of plant g/kwh

5.42 5.11 4.92 5.05

Note In 2006, because of putting into operation of bag filters in No.2 and 4 boilers, the power consumption of that year increased a little.

2.2.2 Summary of transformation project on energy saving The transformation project on energy saving of Yangguang Power Plant includes

four sub-projects. See Table 2.2-2 for details.

Table 2.2-2 Summary of transformation projects on energy saving in Yangguang

Power Plant

Project name Transform

ation content Result of energy

saving Planned

time to realize

Investment

10 thousand

yuan

The

transformation

project of

frequency

conversion of

primary fan from

No.1 boiler,

Installation

of frequency

conversion

equipment to 2

sets of primary

fan

Saving standard coal 1560 t/y, reduction of power consumption for 0.045%, reduction of coal sumption of the whole plant for 0195g/kwh

During minor

maintenance of

No.1 boiler on

Nov. 2008

442


Installation

of online

monitoring

system on coal

as pipe line

Saving standard coal

of 7200t/y, coal

consumption/ group

reducing 3.60g/kwh

During major

maintenance of No.

4 bilor on June

2008

500


Replacing

of steam seals

Reduction of coal

consumption /generator

group off 3.00g/kwh

annually

During major

maintenance of

No.4 group on

June, 2008

120

27



Software

development

Annual consumption

of 4000t standard coal.

Reducing coal

consumption of

0.50g/kwh

During major

and minor

maintenance of

No.1. 2. 3 and 4

boilors on Jan.

2008.

360

Total — 18760 — 1422

2.2.3 Transformation project of primay fan on frequency conversion

in No. 1 Boilor

2.2.3.1 Analysis to the necessity of frequency conversion

transformation There are 4 sets of FWEC D-100 double entering and double going out coal grinding machine positive pressure blowing powder manufacturing system for No. 1 boiler in Yangguang Power Plant: and also equipped with 2 sets of G9-36-1NO171 centrifugal primary fan (each with a rate of 1400KW). At present, the system adjusts the pressure of major pipe of coal and hot wind through the adjusting of baffle at the intake of primary fan, and through the adjusting of load baffle of coal glinding machine to change the contribution power of coal grinding machine. The adjust faffle at the intake of primary fan and load faffle in coal grinding machine have the loss of throttle with relative large amount, resulting in the loss of energy consumption. If changing primary fan into frequency conversion control, theough the adjustment of the rotate speed of the fan, the direct of coal powder production for coal grinding machine can be realized and the loss of throttle can be reduced as well as the reduction of energy consumption be realized.

2.2.3.2 Analysis to designed index of operation of primary fan

Index of primary fan of No. 1 boiler is shown in Table2.2-3

Table 2.2-3 Index of primary fan Operation point Project

TB B-MCR

Wind volume(10 thousand m3/s) 21.74 16.7 Intake temperature(�) 25 25 Intake density (mg/m3) 1.3 1.3

Average air pressure (mmHg) 697.9 —Total pressure (Pa) 15242 10464

Ratio pressure energy (Nm/kg) 5349.2 3855 Rotete speed of shaft of

ventilation machine(R/min) 1490 —

Input power of driving machine 1143 788

28


(KW) Recommended rating power of

driving machine(KW) 1400 —

Motor current (A) 157.7 —

From the above mentioned analysis, we can learn:

�During the normal operation of primary fan of No. 1 boiler, baffle opening condition is about 50-60%, with a great loss of throttle, providing the possibility of transformation of frequency conversion in the field of economy.

�Since the primary fan is operating generally on a set pressure, the primary pressure during the operation is keeping on about 11kPa. After the transformation of frequency conversion, the primary pressure can be reduced into about 9kPa to let the fan realize a specific adjustment to rotate speed.

Therefore, primary fan of No. 1 boiler has the possibility for the transformation of frequency conversion.

�Specific experiment for primary fan on cooling condition On September 2004, during the minor maintenance period of No. 1 boiler, an

experiment was conducted to the operation points on primary fan to associate with the transformation project of frequency conversion on fan for the power plant and to provide base information for the transformation. From the experiment of cooling condition of fan, there is still a large margin for the design of fan. During the experiment, an experiment was conducted to the seal condition of coal grinding machine, when the load baffle was opened to wider than 80%, the pressurized wind pressure could meet the demand.

Therefore, the primary fan on No. 1 Boiler has the possibility for the transformation of frequency conversion.

2.2.3.3 The implementation plan of frequency conversion and

engineering contents.

�Determination of the plan Based on the issues raised through the overall analysis to the primary wind

system and the major and supplementaly machine systems, the final determination of the transformation plan for frequency conversion is: the control plan of one pulling one/ automatic transversion between power frequency and frequency conversion according to the principle of “ensuring the safe and reliable system, reasonable constructure, simple operation and small amount in transformation.

Since there is no standby operation mode and the primary fan system is working with two sets and one fan can only supply 60% load for the group. Under the situation of high load of fan group, the trip of each fan can cause safety problem to the operation of the group though RB system of the group can realize automatic adjustment and reduction of load for major and supplementary system when trip occurs to realize the stable transversion and continuous operation. However, using the

29


automatic transversion plan between power frequency and frequency conversion is to ensure the transition the process of the fan group from frequency conversion to power frequency and the safe operation of the unit.

�Engineering content of transformation The contents of transformation of frequency conversion include: construction of

a frequency conversion control room with 40m2, installation of frequency conversion equipment and transformation of the circuit of fans, the location points of the transformation is shown in Table 2.2-1.

The detailed principle chart of electronic structure of the system is shown in Figure 2.2-2, among which, QF means high pressure switch; QES means the grounding point of high pressure switch; TF means transducer; M means motor. The system is adding QF13 and QF23 high pressure switches at both sides of 6kv major lines to replace QF11 and QF21 to realize the power frequency operation function on the base of existing primary fan, and adding QF12 and QF22 at both sides of transducer to realize the isolation of electricity and gas furing the operation of primary fan.

Figure 2.2-1 The place to conduct the transformation of frequency conversion on

primary fan of No. 1 boiler.

Primary fan Location to set up control room for frequency conversion

30


Figure 2.2-2 Principle chart for major electronic structure of frequency conversion system

To realize the automatic transversion between power frequency and frequency conversion, the system utilizes vacuum breaker as the functioning part for operation which has advantages of high realibility, low malfunction rate, short time in switching onand off and complete protection function. At the same time, an overall design to the control logic of high pressure switch is done to raise the high security and realiability for the system, main including the following aspects:

The transformation has been done to the control circuit of the switching on and off

function of high pressure switch on the upper part of transducer to realize the combined protection function with transducer. When the transducer has not under the condition of supplying power, the high pressure switch allows the loop to prevent malfunction of power supplying; when the major accidents occur on transducer, the emergy switch will shut down the high pressure switch to cut off the power source of 6kv to protect the safety of the system.

Realization of the combinated function to high pressure switch at the lower part of

transducer. When the switch at the lower part of transducer is in the condition of disconnection, the starting of transducer will be prohibited; when the primary fan frequency convension is under operation, and any abnormal disconnection happens at the lower part of the switch, the frequency conversion system will issue the abnormal signal to ensure the primary wind system can response an emergency reaction to the accident.

Through the realtime monitoring and treatment to the working point of the

operation by the combination of upper high pressure and lower high pressure switches of transducer and the judgement and analysis of the location of the failure by primary wind system by different grades and points to make a

31


judgement of the actual situation of failure fro 6kv net side, equipment, primary fan and load. Through the comprehensive treatment and analysis, automatic functions of checking and treatment will be realized under the situation of happening any failure. Under the emergency, the system will determine the frequency conversion of primary fan should be switched to power frequency when the frequency conversion shuts down.

Installation of synchronizated power switch system to realize fast switch from

frequency conversion into power frequency operation mode of primary fan after checking out that the failure point is not the problem of the primary fan or motot to gurantee the primary wind system not to lose pressure or switching off the fire.

To avoid the short circuit for power frequency and frequency conversion, two

isoletad and blocked electronic circuits are located at high pressure switch of the lower part of transducer and the high pressure switch of power frequency, realizing a hard connection through the circuit on the one hand and a soft connection through the primary wind system logic on the other hand to function as two different level of protection.

The groundings located in lower part high pressure switch and power frequency

high pressure switch of transducer have mutually locked function to prevent the occurance of malfunction when the machine is under operation or under maintenance and avoid the happening of serious accidents. When one side is under operation, the system will lock the other side grounding to prohibite the gounding action at other other; when one side is switching into grounding function, the operation of primary will be prohibited.

Realization of automatically transversion between power frequency and frequency

conversion freely according to the need of the operation to ensure the retreat of transducer under the situation of failure and re-connection stably under the situation becomes normal.

The control and logic treatment circuit of the system switch and transducers are all

under control by automatic control system of frequency conversion.

2.2.3.4 Newly adding equipment and demand of technical index for frequency

conversion transformation

�The new equipment needed to add for the transformation of primay fan

The list of the equipment needed to added is shown in Table 2.2-4

Table 2.2-4 List of newly added equipment for transformation of frequency conversion for primary fan

Series Name Amount set

32


No. 1 High pressure transducer 2 2 High pressure switch box 4 3 Heat exchanger 2 4 Axil flow fan 380VAC 2 5 Sychronized power switching equipment 2

�Required technical index of transducer

The detailed technical index is shown in Table 2.2-5

Table 2.2-5 The technical index of transducer

Series

No. Name Index

1 Transducer capacity (KVA) 1400

2 Qualified motor rate (KW) 1400

3 Input frequency (Hz) 45 55

4 Rating input voltage (V) 6000V+5%/-10%

5 Input power factor 0.95 >20% load

6 Tranducer efficiency Under rating load >0.96

7 Out frequency range (Hz) 050

8 Output frequency resolution (Hz) 0.01

9 Over loading capacity 120% per minute 150% protect

immediately

10 Simulated input 0 10V/4 20mA design as one wish

11 Simulated output 2 lines, 010V/4 20mA selectable

12 Time to accelerate and reduce(s) 0.13000

13 Environment temperature under

operation �0 40

14 Temperature on storage/transportation� -40 70

15 Environmental humidity

33


degrees), the plant can decrease the coal consumption of 0.195g/kwh, save 1560 tons of standard coal annually, if calculated as 300yuan per ton, the plant can have a benefit of 468,000 yuan annually.

34


2.2.4 Installation project of online monitoring on coal powder pipe of No. 4

Boiler.

2.2.4.1Analysis to the necessity of installation of online monitoring system During the operation of thermal power plant, the coal powder density within the powder piping system of boiler combustion system, i.e. primary wind coal density is the important factor. The high and low of coal density directly influences the equality of powder transmitted in the pipe, the stability of working point in the chamber and the effeiciency of combustion in the boiler chamber. At present, there is no online monitoring system equipped on pipe of coal transmission, the major issues are the followings:

� There are measuring holes on the pipes of existing system which are used for the measurement of off line wind speed when combustion is operation in the boiler, but it is impossible to realize online measurement to coal density, speed of coal powder flow and the controllers can not have a good control to coal powder index entering into the boiler chamger and it is impossible for them to make an adjustment in time according to the situation.

�There are few intersects between the steam and water systems of the boiler in the plant, resulting in the unequality of coal powder for primary wind under operation which can cause the decline of blaze in the chamber easily and let specific part of heating become overheated and effect the safe operation of boiler.

�Because of the different density of coal powder coming out from the fire mouths with different widths on hearth under the operation of boiler, when the specific part is in high density, the supplied wind is not enough and effect the complete combustion of coal powder; when the specific part is in low density, the stability of consbustion will be effected.

�When the coal powder density in the pipe is too high and the wind speed is too low, the jam in the coal powder transmission pipe will occur even the result of the accidents as firing of coal powder pipe.

Therefore, after the installation of only monitoring system on the pipe and we can measure the equality of coal density of primary wind and the equality of the coal powder transmission, under the coal powder flow and density realtimely, and make fast djustment in time according to the measurement result, we can realize the optimization of combustion, let it more stable, reduce carbon content of ash, more stable hearth temperature and improve the boiler efficency.

2.2.4.2 Analysis to the feasibility of installation of online monitoring system Our focus is the analysis to the influence of the equality of coal powder to

combustion. The boiler of No.4 generator group of the plant is B&WB-1025/18.3M”W” type

blaze, mid-storage, subcritical, primary middle reheating and natural circulation steam turbine produced by Beijing Bawei Boiler Factory. There are 16 burners in it. Because of the different distributions of powder supplying pipes of powder supplyer and

35


primary wind pipes, the different resistances of coal powder pipe occur, which will cause the larger difference to the speed of coal powder pipe and difference in the coal powder volume under transmission, the density and equality of coal powder have much greater diffeence.

During the actual combustion process, the speeds of wind and powder mixed at the mouth of coal powder pipe are changing very rapidly and frequently within a wide range as the changes of combustion and coal quality, and they are influencing the stability of combustion. If we want to maintain the stable of combustion and raise the burning efficience, it is necessary to continuously measure and adjust the density and equality of coal powder. Through the observation to the influence of coal powder equality to the combustion under the manual cooling and heating admustment of the boiler combustion, the result is that under the condition of equal coal powder, the combustion is stable, the negative hearth pressure wave is small, carbon content of ash is low and the whole earth temperature is very equal.

Therefore, the equality of coal powder is very important to the combustion. If we can have a realtime measurement and adjustment to the equality of coal powder according to different load and coals under operation, we can increase the burning efficiency of boiler and realize the energy saving and emission reduction.

2.2.4.3 Implementation plan and project component of installation of online

monitoring system �The determination of the plan Through the analysis mention above, the coal powder density- primary wind coal

powder density within the powder transmission of boiler burning system is a critical factor. Therefore, it is necessary to install online monitoring system on coal powder pipe. The determination of the measurement method for the plan is electric charge induction method from the direct methods.

The operation theory of the method is that: During the process of coal block being grinded in the grinding machine, the process of coal being smashing and the process of being transmitted, the coal powder grain always hits the pipe wall, friction and distribution with the pipe wall always happen, and even among the coal powder grains, the crash, friction and distribution are always happening. Such kind of processes with a great volume and close contact and separation can bring coal powder with curtain amount of static charge. The coal powder grain with static charge can produce curtain amount of static fields. When they are passing through the metal sensors, the surfaces of the sensors can produce the equal amount of inductive charges. When a large amount of coal powder with charge is passing through the sensors, the inductive electric current will be formed on the surface of the sensors. There is a relationship between the volume of inductive electric current and the flow volume of coal powder flow passing through the sensors. Setting inductive electric current as the measurement signal, and through the analysis and treatment of them, we can get the density signal of coal powder. At present, this method has been already put into industrial utilization with a good result.

�Engineering content of transformation

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The whole online monitoring system is composed of three parts as sensor, on the spot box and central control computer, needing to install 16 sets of measurement equipment in total.

The place of transformation is shown in Figure 2.1-2 and the detailed part to be transformed is shown in Figure 2.2-3.

2.2-3

Figure 2.2-3 The location on coal powder pipe of No.4 boiler where online monitoring system to be installed.

To install the sensors on coal powder pipe, then send the signal colleted through the induction to on the spot box through coaxial cable for the treatment. After the treatment, send the signal through the cable to the central computer. The computer will make analysis and treatment to the received data to calculate the flow speed, flow volume and equality of coal powder passing through in the pipe, and display them on the screen and send them to DCS system of power plant through network for the data optimization for the combustion for the program. The operation theory sketch map of online monitoring system on coal powder pipe is shown in figure 2.2-4.

Coal powder transmission pipes outside the major workshop

The location on coal powder pipe where the online monitoring system to be installed.

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Powder house

Powder supplier

Primary coal powder pipe

Downloading

Powder pipe Primary

Boiler bellow

sensor sensor

Figure 2.2-4 The operation theory sketch map of online monitoring system on coal

powder pipe

2.2.4.4The equipment needed to newly added and technical index for online

monitoring system on coal powder pipe �New equipment to be added 16 sets of online monitoring system on coal powder pipe. �Technical requirement Detailed technical index is shown in Table 2.2-6 Table 2.2-6 Technical index of online monitoring system on coal powder pipe

Series No. Name Perameter

1Measurement range of coal powder density (kg powder/ kg gas)

0.2 2.0

2m/s Measurement range of speed

(m/s) 5 50

3Measurement precision of coal powder density (kg powder/kg gas)

±0.1

4 Measurement precision of speed (m/s) ±1.0

Amplifi Amplifier

PC

38


5 Working temperature of sensors � �300

6 Power voltage (v) AC220±10%

7 Power consumption (kw) �3

2.2.4.5 Analysis to the result of installation of online monitoring system on coal powder pipe

Installation of online monitoring system on coal powder pipe can realize the continuous measurement of coal density and the speed, through the adjustment and control of primary wind, the coal powder entering each burner can become equal, the wind speed can be reduced, power consumption of fan be decreased, fineness of coal powder be improved, combustion be more completed, stable and the efficiency of machine be increased.

After the transformation, carbon content of ash is �5%; the efficiency rate of boiler increases 1%, which can be converted into the reduction of coal consumption 3.6/kwh per machine, saving 7200 tons of standard coal annually, if calculate as 300 yuan per ton of standard coal, we can have a benefit of 2.16 million yuan each year.

2.2.5 Transformation project of steam seal of No.4 boiler

2.2.5.1 Analysis to the necessity of the transformation of steam seal

At present the issues existing in No.4 group are as follows:

� A large leakage amount in high pressure rear shaft seal and middle pressure rear seal and water leaking into tank is serious.

� The large clearance in low pressure front and rear seals influences the vacuum of condenser, resulting in the frequently dis-qualification of the tightness test of vacuum and affecting the economic and stable operation of the machine.

� The clearance between seals on the top of high and middle pressure cylinders much larger than standard, and the steam seal on top of high and middle pressure cylinders is unadjustable which is one of the major reasons causing the low heat efficiency of cylinder.

� Steam leaking volume in steam seal on two sets of minor machines is the major reason of low vacuum of the major machine.

Therefore, the issues of low efficiency of high and middle pressure cylinders, large consumption of steam and low efficiency of turbine of No.4 steam turbine are needed to be transformed to the steam seal urgently.

2.2.5.2 Analyhsis to feasibility of steam seal transformation

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� The steam seal used in the end of the shaft of high and middle pressure is the type of labyrinth, and through the utilization of this kind of steam stem turbine group should meet the standard of steam sealing according to the point of theory but there are some problems existing in the actual operation, the most important issue is that it is very difficult to ensure the clearance value of steam seal. If the adjustment of the clearance is too big, it will result in the poor tightness of steam seal, steam leaking in some parts, and reduction of heat economy of the machine and it can also cause the accidents as water entering into oil happening frequently; if the adjustment of the clearance is too small, it is easy to cause the friction between steam seal and shaft surface, and when the friction is serious, it can cause the happening of safety problems as the bending of shafte because of overheated of the shaft surface and vibration problems. Is is calculated that whenever the steam leaking volume of steam seal on the shaft of high pressure cylinder increases 1t/h, the energy consumption will increase 4.8kJ(kw.h).

� The flow clearance between high and middle pressure cylinders is too big. The steam seal on cylinder top has never been replaced since putting into operation and it is still the traditional steam seal of labyrinth type. Because of the factors as invalidation of the spring of press plate for steam seal after using for a lont time, existing of oxide skin and rust dirt in the flow area and the distoration of steam seal, steam seal body, the steam seal can be blocked in the groove and not to concede. To ensure the avoiding of wearness of steam seal after starting, the clearance of steam seal has to be enlarged during the maintenance but this cause the increase of steam leaking between the parts and great reduction of turbine effiency but we have to sacrifice the economic capacity to ensure the security.

�The steam seal of low pressure shaft end uses slanting flat tooth steam seel. To ensure that there is no friction in movement part when starting, the standard for the clearance when installation and adjustment have to use the upper limit one, but this will cause a large volume of steam leaking. The larger clearance between steam seal at low pressure shaft end will cause the leaking of air into condenser, reduction of vacuum. When the 50g/h aire is leaking into condenser, the vacuum of condenser will reduce 1kPa, the heat consumption of the turbine will increase 0.6-0.8%.

To reduce energy consumption, increase the economic capacity and security of the turbine group and solve all the above questions, we are going to implement the transformation to high and middle pressure shaft end steam seal, top steam seal and seals at shafts of two small machines in No.4 turbine through the combination with the successful experience of the plant to the steam seal transformation of No. 2 and 3 turbines.

2.2.5.3 Content of steam seal transformation project

�Content of transformation project

�Transformation of high and medium pressure shaft seal, high and medium

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steam seal 29 rings at total.

�24 rings of steam seal from front and rear shafts of two small machines transformation.

�Transformation of high and medium pressure top steam seal and low pressure top steam seal 25 rings in total.

The location of transformation is shown in Figure 2.1-2 and the detailed part is shown in Figure 2.2-5.

Figure 2.2-5 Detailed part of steam seal transformation in No.4 boiler

�The advantage of the plan

The contact type steam seal is a kind of steam seal without any clearance, i.e. there is no any clearance between shaft and steam seal to realize the clearance that traditional clearance steam seal (traditional steam seal belongs to clearance steam seal) can not rea

transformation project on energy saving and emission reduction … · 2016. 7. 13. · wet method...

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