Thermal Power Plants in India

According to Central Electricity authority of India, there were 83 coal fired thermal power are plants existing in India on March 31, 1998. Thermal power (coal, diesel and gas) generation during was 338104 and hydro-power generation was 74582 GWH.

Coal consumption by various plants in the country during the year 1997-98 was 202.75 million tons. The specific coal consumption in 1997-98 is 0.73 kg/ kWh. Average heat input for all the power p 2801 kcal/kWli in 1997-98. Some power plants are more efficient than others. The efficient der combustion technology, operating conditions, and the coal fired thermal power plants, 13 power plants, having aggregate installed capacity of 7594 MW, produced 43387 GWH. Represents 11% of total steam generation and an overall thermal efficiency of less than 25%. 42p with an aggregate installed capacity of 27080 MW had an overall thermal efficiency between 25% generated 183558 GWH, which is 46% of total steam generation. 26 power plants with aggregate 24850 MW had an overall thermal efficiency above 30% and produced 171349 GWH representing steam generation.

Anthropogenic Emissions

Anthropogenic emissions from energy activities in India: Generation and source characterization.

Emissions from coal fired Thermal Power plants in India: Based on the input parameters and the ultimate analysis of coal used for power each of the Power generation, emission of CO-,, SO-, NOx, Soot Carbon and particulate matter (SPM) from each of the Power plant has been computed.

Input parameters-Actual air supplied (during operation) electric power generated per day and coal used for unit power generation, For boosting combustion small amount of diesel oil and furnaces oil (FO) as supplementary fuel is used.

NTPC Run Thermal power plants

Supplementary fuel consumption is 0.2 to 0.3 ml / Unit of Power in old plants they range from 1 to 4% of the Fuels Emission form these supplementary fuels is not accounted in the computations. Ultimate analysis available from seven thermal power plants namely Chandrapur, Dhana, Singrauli, Dadri Rihend, Kutch and Nayveli are used most thermal power plants in India use E and F grade coals only. AN Average ultimate analysis of coals (E and F grades) as given in Table 3.5.2 is used for remaining 74 thermal power Plants Nox calculations assume equilibrium reactions and 1700 К gas temperature. CO, emissions are estimated based on the carbon content in the coal and the excess air used in its combustion. 12% carbon based on the no measurement data it is assumed that 10% carbon remains unbumt- and mixes with the ash and 2% carbon forms soot) is subtracted before calculating emissions of CO, (Assuming 88% of carbon to undergo combustion)

CO, emissions from power plants per day (Computed)

C02 (Thousand tons per

No of power plants

Coal used per day million tons)

40-50

5

0.16

30-40

3

0.08

20-30

9

0.15

10-20

24

0.3

0.10

40

0.43

Total C02 emissions from all power plants (coal fined) in India was 1.1 thousand tons per day during the year 1997-98 on 395 million tons per annum (computed). Yearly estimates of power generation and emission are based on the plant load factor (PFF) is the ratio of actual power generation and installed capacity CO, emission from power Sector in India for 1990 is 213 million tons.

= CO, emission from Power Plants per day (Computed)

Total C02 emissions from all power plants (coal fined) in India was 1.1 thousand tons per day during te year 1997-98 on 395 million tons per annum (computed). Yearly estimates of power generation and emission are vased on the plant load factor (PLF) is the ratio of actual power generation and installed capacity CO, emission from power sector in India for 1990 is 213 mission tons.

= CO, emission per unit of electricity generated (computed)

C02 (kg/kWh)

No of Power Plants

1.4 to 1.8

4

1.2 to 1.4

9

1.0 to 1.2

27

0.8 to 1.0

40

0.6 to 0.8

1

Most power plants CO, emission range between 0.8 and 1.2 kg/kWh same between 1.2 and 1.4 kg/kWli, Four have more than 1.4 kg/kWh this reflects operational efficiency due to poor coal quality of operating conditions one power plants has CO, emission less than 0.8 kg/kWh SO, emissions : Sulphur content in Indian coal as compared US coal is low Assuming that no control technology is used SO, emissions from all the power plants (Coal fired) in India per day is estimated as 7.6 thousand tons per day and 2.8 million tons per annum. Average SO, emission of Indian Thermal Power Plants has been found to be 7.4 gm/kWh. The lignite based power plants have maximum S02 emission/kWh generated (e.g., most of the other plants emit between 4 to 9 gm SO,/kWli.

NOx Emissions

Are based on equilibrium reaction and average gas temperature of 1700 K, in reality the gas temperature in the boiler varies from 900 to 2500 К an reaction also occurs is several phases, present estimate of NOx emission from thermal coal fired Power Plants in India is 7.9 thousand tons per day and 2.9 million tons per annum. The Nellore Thermal Power plant emits the largest of NOx per unit of electricity generated with a value of 13.1 gm/kWh. Plants like Faridabad, Harduaganj, Tanda, Korba II and III, Kothagundem, Barauni, Muzaffeipur and Patram are also amongst the larger emitter of NOx/kWli - emission ranges from 10-12 gm/kWli, most of other plants emissions of NOx are in the range of 6-10 gm/kWh.

Soot Emissions

Approximately 67 toii/day on 24 thousand tons per year is estimated to be emitted from thermal power plants in India during 1997-98. Emission factor 0.08 gm/kg of coal and 0.06 gm/kg of lignite in Indian Power plants. Nellore thermal coal fired ower plant with an estimated 0.1 gm/kWh has been found to be the largest emitter (e.g. Kutch 31 gm/kWh, Nyvet 18gm/KWH, Nyveli 10 gm/kWh of Soot. The other large emitter Thermal Power Plants include Faridabad, Harduaganj, Korba II, and III, Kothagudenn, Beraun, Muzzaferpur and Talcher where the soot emission range from 0.08 to 1.0 gm/kWh.

Fly Ash Pond / Pitash Emissions

The ash content in the coal consumed in thermal power plants is responsible for 2.3 thousand tons of SPM in the form of fly-ash per day and 0.8 million tons SPM per annum. The chondrapur, Kothgudem Nellore Baraumi and Muzaffarpur thermal Power Plants have been found to be amongst the largest emitter of SPM per kWh generated about 3 to 3.5 gm of SPM/kWh has been estimated to have been emitted from these plants. Plants like Faridabad, Harduaganj, Obra, Panki, Paricha, Tanda Korba II & III Satpura Emnore Patratu Calcutta, New Cassipore, Talchar NTPC and IB vally TPS emit in the range of 2.5 to 3 gm SPM/kWh. Rest of the plant have SPM emission lower than 2.5 gm / KWH.

 
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