Vocational Training at NTPC Farakka

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

2. CONTENTS
1. Basic requirements of a Thermal Power Plant
2. NTPC Farakka
3. Different plants
4. Main Plant
5. Coal handling plant
6. Boiler and water walls
7. Turbines and Generators
8. Condensor and cooling water system
9. Draught system
10.Ash collection and disposal system
11.Offsite plants
12.Conclusion
13. References
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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
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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
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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
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7. Main Plant
Economizer inlet
valve
Through
Downcome
r
Through Furnace
Steam
Water
Steam
HP Turbine IP Turbine LP Turbine
Boiler stop
valve
Steam
CW in
CW out
Water
Drain Make-up Drain Make-
up Drain
Drain
Drain
Make-up
Make-upMake-up
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8. Coal handling plant
8

9. Wagon tippler & Conveyer belt
9

10. Coal mill
10

11. How coal mill works
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12. Inside of a boiler
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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
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14. Water wall
Water Wall and Superheater :
1. 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.
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15. BOTTOM RNG HDR & Z-PANEL 1ST PASS W.W
1ST PASS W.W O/L HDRS ROOF I/L HEADER
2ND PASS UPPER C-HDR 2nd 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
2ND PASS ROOF O/L HDR(REAR ECONOMISER
M.S
H.
R.
HC.R.H
FROM F.R.S
15

16. 16

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
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18. Ash collection and disposal system:
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 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.
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

20. 20

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.
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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:
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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 H2 is generated for
cooling purpose of generators. H2O is passed through cell and by
electrolytic process H2 & O2 is generated. H2O ---------> H2 +
(1/2)O2 .
Previously oxygen used to be stored also. But nowadays it is
directly send to the atmosphere.
3.Cooling Water Pump House(CW Pump House):
Hot
water
Through Open
Air Channel
Cold Water
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24. Conclusion:
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 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:
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26. Thank you
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