NTPC Farakka

Vocational Training at NTPC Farakka

1. By:- GOVIND KUMAR MISHRA ROLL NO. :- 14/ME/032 1 VOCATIONAL TRAINING (NTPC Farakka )

2. CONTENTS Basic requirements of a Thermal Power Plant NTPC Farakka Different plants Main Plant Coal handling plant Boiler and water walls Turbines and Generators Condensor and cooling water system Draught system 10.Ash collection and disposal system 11.Offsite plants 12.Conclusion 13. References 2

3. Basic requirements of a Thermal Power Plant Location ( Near to water sources and mines) Fuels ( eg . Coal,oil etc.) Water Resources ( eg . Rivers ) 3

4. Different Plants: Main Plant Water Treatment plant Coal Handling Plant Hydogen generation plant HFO Pump house Ash collection and disposal system 4

5. Overview of ntpc farakka   Stage     Unit Number   Installed Capacity (MW)   Date of Commissioning   First     1   200   January, 1986   First     2   200   December, 1986   First     3 200   August, 1987   Second     4   500     September,1992   Second     5   500   February, 1994   Third     6   500   April, 2012   Total     Six   2100   5

6. Typical diagram of coal fired thermal power station 1. Cooling Tower 10. Steam Control Valve 19 .Superheater 2. Cooling Water Pump 11. HP Steam Turbine 20. Forced Draught (Draft) Fan 3. Transmission Line (3-Phase) 12. Deaerator 21. Reheater 4. Step-up Transformer (3-Phase) 13. Feedwater Heater 22. Combustion Air Intake 5. Electrical Generator (3-Phase) 14. Coal Conveyor 23. Economizer 6. Low Pressure Steam Turbine 15. Coal Hopper 24. Air Preheater 7. Condensate Pump 16. Coal Pulverizer 25. Electrostatic Precipitator 8. Surface Condenser 17. Boiler Steam Drum 26. Induced Draught (Draft) Fan 9. IP Steam Turbine 18. Bottom Ash Hopper 27. Flue Gas Stack 6

7. Main Plant Boiler Feed Pump (BFP) High Pressure Heater 5 (HPH5) High Pressure Heater 6 (HPH6) Economizer inlet valve Economizer Boiler Drum Ring Header Through Downcomer Water Tubes Through Furnace Low Temp Super Heater (LTSH) Steam Water Platen Super Heater Final Super Heater Steam Reheater HP Turbine IP Turbine LP Turbine Condenser Boiler stop valve Steam Condensate Extraction Pump (CEP) De-aerator Gland Steam Cooler Drain Cooler Low Pressure Heater 1 (LPH1) Low Pressure Heater 3 (LPH3) Low Pressure Heater 2 (LPH2) CW in CW out Water Drain Make-up Drain Make-up Drain Drain Drain Make-up Make-up Make-up 7

8. Coal handling plant Coal Delivery Unloading Preparation Transfer Outside storage (Dead Storage) Covered storage (Live Storage) In plant handling Weighting and measuring Furnace 8

9. Wagon tippler & Conveyer belt 9

10. Coal mill 10

11. How coal mill works 11

12. Inside of a boiler 12

13. Boiler drum Function of Boiler Drum:   1. To provide the necessary space for separation of steam from mixture of steam and water.   3. To house the equipment needed for purification of steam after separation from the mixture of steam and water. 4. To provide a water storage for preventing the starvation of tubes during Operation 13

14. Water wall Water Wall and Superheater : Heating and evaporating the feed water supplied to the boiler from the economisers. 2. These are vertical tubes connected at the top and bottom to the headers. 3. These tubes receive water from the boiler drum by means of downcomers connected between drum and water walls lower header. 4.Approximately 50% of the heat released by the combustion of the fuel in the furnace is absorbed by the water walls. 14

15. BOTTOM RNG HDR & Z-PANEL 1 ST PASS W.W 1 ST PASS W.W O/L HDRS ROOF I/L HEADER 2 ND PASS UPPER C-HDR 2 nd PASS LOWER C-HDRS LTSH I/L HEADER LTSH O/L HEADER D.P.I/L HEADER D.P.O/L HEADER S.H. HEADER R.H.HEADER 2 ND PASS ROOF O/L HDR(REAR ECONOMISER M.S H.R.H C.R.H FROM F.R.S 15

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17. Condensor and cooling water system The Stator water is cooled and fed back to the stator through pumping via condensers which condenses or cools the hot stator water. The Pressure gauge provided over the condenser gives the measure of pressure of condensed water inside the condenser. By condensing the exhaust steam of a turbine at a pressure below atmospheric pressure, the steam pressure drop between the inlet and exhaust of the turbine is increased, which increases the amount of heat available for conversion to mechanical power 17

18. Ash collection and disposal system: 18 80 % of the ash is dry ash ,which is collected through Electrostatic precipitator. ESP:

19. ASH POND : Life of a power plant is estimated by the time required to fill the pond ash .It is generally 30-35 years. 19

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21. 5. Cooling Tower: Generally there are 2 cycle in a power plant. Closed cycle and Open Cycle. Closed cycle needs cooling tower, but in open cycle the feed water is taken from feed water canal and again the hot water from condenser is directly send to the feed water canal again. In NTPC Farakka , we have only 2 sets cooling tower for unit 6 for 500MW plant. So for stage 3 the cycle is closed whereas for stage 1 and 2 the cycle is open cycle. 21

22. 4. DM Plant: De mineralized Plant is used to remove the impurities from the raw water taken from feeder canal. There are many steps in working of DM Plant: 22

23. Offsite plants 1 .HFO Pump House(Heavy Fuel oil Pump House): Heavy fuel oil mainly diesel is used as HFO in thermal power plant to ignite the burning process in the furnace. 2. Hydrogen Generation Plant: : In this Plant H 2 is generated for cooling purpose of generators. H 2 O is passed through cell and by electrolytic process H 2 & O 2 is generated. H 2 O ---------> H 2 + (1/2)O 2 . Previously oxygen used to be stored also. But nowadays it is directly send to the atmosphere . 3.Cooling Water Pump House(CW Pump House): condenser Cooling tower Hot water CW Pump House Through Open Air Channel Cold Water 23

24. Conclusion: 24 In India 73 % electricity is generated by thermal power plant and NTPC is contributing a major role . NTPC Farakka is well situated on the basis of requirements for a thermal power plant and generates appreciable amount of electricity . NTPC Farakka distributes electricity in Bihar(23%), West Bengal(40%), Odisha (20%) and (10-15)% remains unused.

25. Reference: 25

26. Thank you 26