G.K.Pandey, Advisor, Ministry of Environment & Forests, (Govt. of India)

S.K.Tyagi,Scientist, & B.Sengupta,Member SecretaryCentral Pollution Control Board,New Delhi (INDIA)

Paper presented at BAQ 2006 at Yogykarta,Indonesia

MANAGEMENT OF THERMAL POWER PLANTS IN INDIA

Coal, oil, gas and hydroelectric potential constitute the conventional sources of electricity generation. Total installed capacity of electricity generation in India is approx. 98,668 MW.

India ranked third in the world with 7 percent coal reserves of the total world reserves.

Coal production increased from 30 million tonnes to over 348 million tonnes in 1999. Expected to increase to 427 million tonne in 2010.

Seventy percent of the total coal produced is consumed for power generation. Steel & cement are other major consumers.

COAL AND ENERGY SCENARIO IN INDIA

Summary Table of Electric Power Generation

Source India Japan U.S.Coal 59.2% 21.2% 51.8%

Oil 13.9% 16.6% 03.1%

Gas 06.3% 22.1% 15.7%

Nuclear 02.5% 30.0% 19.9%

Hydro 17.8% 08.2% 07.4%

Others 00.3% 01.9% 02.2%

ENVIRONMENTAL ISSUES IN COAL BASED POWER GENERATION

Air Pollution :- High particulate matter emission levels due to burning of inferior grade coal which leads to generation of large quantity of flyash

Emissions of SO2, NOx & Green house gas (CO2) are also matter of concern

Water Pollution :- Mainly caused by the effluent discharge from ash ponds, condenser cooling /cooling tower, DM plant and Boiler blow down.

Noise Pollution :- High noise levels due to release of high pressure steam and running of fans and motors

Land Degradation :- About 100 million tonnes of fly ash is generated by use of coal far energy production. The disposal of such large quantity of fly ash has occupied thousands hectares of land which includes agricultural and forest land too.

ISSUES IN POWER SECTOR Seventy one per cent of electricity production is based on coal

and gas in the country.

83 coal based thermal power plants with total generation capacity of 62880.9 MW (as on July, 2003)

27 gas/naphtha based power plants with total generation capacity of 11299.6 MW (as on July, 2003)

More than 240 million tonnes of coal with ash content 35-45% is consumed annually by the Thermal Power Plants.

3715 MT/day of SO2 is emitted from coal based power plants,which is 89% of total emission of SO2 from industries in India

Nearly 100 million tonnes per annum coal ash is generated.

More than 25,000 hectares of land has been occupied for conventional disposal of ash.

More than 630 million M3 water is required for disposal of coal ash as in slurry form per annum

POLLUTION LOAD FROM COAL BASED THERMAL POWER PLANT

Pollutants Emissions (in tones/day)

CO2 424650

Particulate Matter

4374

SO2 3311

NOx 4966

Emission Estimates

Share of Suspended Particulate Matter Load (tonnes/day) by Different Categories of

Industries (With Control Device), Total Load = 5365 tonnes/day

Sugar10%

Thermal Power Plants82%

Others 1%

Cement7%

Others1%

Oil Refineries3%

Sulphuric Acid Plants

2%

Thermal Power Plants89%

Steel5%

Share of Sulphur Dioxide Load (Tonnes / Share of Sulphur Dioxide Load (Tonnes / day)day)

By different categories of IndustriesBy different categories of Industries(Total Load = 3715 Tonnes / day)(Total Load = 3715 Tonnes / day)

EMISSION STANDARDS FOR THERMAL POWER PLANTS

Depending upon the requirement of local situations, which may warrant stricter standards as in case of protected areas the State Pollution Control Board within the provisions of the Environmental (Protection) Act, 1986, may be prescribed limit of 150 mg/Nm3 irrespective of the generation capacity of the plant

Power Generation Capacity

Particulate Matter Emission

< 210 MW 350 mg/Nm3

= > 210 MW 150 mg/Nm3

For the proper dispersion of SO2 emission from thermal power plant, stack height criteria have been adopted in country. However, for larger capacities boilers (500MW and above) space provision for installing FGD system has been recommended.

Power generation capacity

Stack Height (mts.)

Less than 200/210 MW H = 14 (Q) 0.3 , where Q is emission rate of SO2 in kg/hr,

H= Stack Height 200/210 or less than 500

MW 220

500 MW and above 275

STACK HEIGHT REQUIREMENTS

Status of Pollution Control in Thermal Power Plants in India

Total number of power plants : 81 

Air Pollution

         Power plants complying with emission : 43 standards         Power plants not complying with emission : 35 standards         Power plants closed : 03 

Water Pollution          Power plants complying with ash pond : 49 Effluent standards         Power plants not complying with ash pond : 29 Effluent standards         Power plants closed : 03

REASONS FOR NON-COMPLIANCE OF ENVIRONMENTAL STANDARDS IN

THERMAL POWER PLANTS 

        Inconsistent supply of coal

        High resistivity of coal

        Inefficient operation of ESPs

        Delay in supply of ESPs

       Low Specific Collection Area (SCA) of ESPs

        Inefficient management of ash ponds

        Large quantities of ash generation

CLEAN COAL TECHNOLOGIES (CCTS)

Need for adoption of CCTs

To meet in creasing demand of power with minimal environmental impact for sustainable development, adoption of clean coal technologies with enhanced power plant efficiency, fuel switching, use of washed coal, efficient pollution control systems and proper by-product and waste handling & utilization, is necessary.

Classification :

Pre-combustion Technologies : Ash, sulphur and other impurities (coal benefaction) ca n be reduced from the coal before it is burned

Combustion technologies : Generation of emissions of SO2, NOx (FBC : CBFC, AFBC,PFBC, and CO2 can be minimised by

IGCC) adopting improved combustion technologies

Post combustion technologies : End of pipe treatment (installation pollution

control equipments such as ESP, DENOx & De SOx systems)

USE OF BENEFICIATED COALIn order to minimise fly ash generation, it was recommended to use beneficiated coal in the power plants. A Gazette notification has been issued under EPA, 1986, stating that :

“On and from the 1st day of June 2002, the following coal based thermal power plants shall use beneficiated coal with ash content not exceeding thirty four percent, namely :

Power plants located beyond 1000 km from the pit head and

Power plants located in urban area or sensitive area or critically polluted area irrespective of their distance from the pit head except any pit headed power plants.

The power plants based on FBC (CFBC, PFBC & AFBC) and IGCC technologies are exempted to use beneficiated coal irrespective of their locations.

ADVANTAGES OF BENEFICIATED COAL Implementation of use of beneficiated coal in thermal power plant w.r.t. June 30, 2002, shall yield following benefits during 2002-03:

Reduction in tonnage (MT) 11

Saving in transport cost (US M$) 240

Saving in Diesel consumption (KL) 63750

Reduction in Bottom Ash (MT) 2

Reduction in Fly Ash (MT) 8

Reduction in CO2 (MT) 23

Out of 81 coal based thermal Power plants, 39 plants are required to use beneficiated coal not containing ash more than 34% w.r.t. June 30, 2002.

GOVERNMENT INITIATIVESMinistry of environment and forests has issued following directions under section 3 & 5 of Environment (Protection) Act, 1986 vide a Gazette notification no. GSR . 763 (E) dated 14/09/1999

Use of flyash, bottom ash or pond ash in the manufacture of bricks and other construction activities

Utilisation of flyash by thermal power plants and

Specifications for use of flyash based products by Government agencies

Action Plans for utilisation of Flyash by Thermal Power Plants

Out of 81 power plants, 52 power plants have been submitted their action plans remaining have been asked to submit action plans immediately.

Submission of action plans by the Submission of action plans by the power plantspower plants New Power PlantsNew Power Plants• 30 % flyash utilisation within 3 year30 % flyash utilisation within 3 year• 100 % flyash utilisation within 9 100 % flyash utilisation within 9 yearsyears

Existing Power PlantsExisting Power Plants• 20 % flyash utilisation within 3 20 % flyash utilisation within 3 yearyear• 100 % flyash utilisation within 15 100 % flyash utilisation within 15 yearsyears

Conclusions• Existing coal based power plants being

monitored by the regulatory agencies and directions are issued

• Use of Beneficiated Coal in Thermal Power Plants

• Emphasis on clean technology for new plants• Emphasis on utilisation of fly ash• Emphasis on non-carbon/low carbon based

technologies for power sector• Emphasis on on cogeneration

Thank you