1. -:A SUMMER TRAINIG
EXPERIENCE:
IN
-:NATIONAL THERMAL POWER PLANT{DADRI}:-
 PRESENTED
BY:
EMAM RAZA

ROLL.NO-1002940032

M.E STUDENT OF
KIET(GZB)
UNDER THE GUIDANCE OF:-
MR. R.K SHINHA
DGM, EE Department of power plant
(DADRI)

2. -:About NTPC:•
•
•
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•
•
•
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•
NTPC, the largest power Company in India, was setup in 1975 to accelerate
power development in the country.
Dr.Arup Roy choudhary is chairman & MD since 1/09/2010.
NTPC has installed capacity of 41,684 MW.
NTPC ranked 300th in the ‘2013, Forbes Global 2000’ ranking of the World’s
biggest companies.
NTPC plans to become a 128,000 MW company by 2032.
It has 16 coal based power stations (23,395 MW)
7 gas based power stations (3,955 MW)
4 power stations in Joint Ventures (1,794 MW).
NTPC has been awarded NO-1,best workplace in india among large
organization and the best psu for the year 2010.

4. -:NTPC, DADRI:TOTAL CAPACITY OF DADRI POWER PLANT :(A) THERMAL
I:- 04X210 MW = 840 MW
II:- 02X490 MW = 980 MW
TOTAL
= 1820 MW
B)
GAS
(C) SOLAR
= 817 MW
= 05MW
GRAND TOTAL = 2642 MW

5. PMI Revision 00
October 14, 2013
5

6. Diagram of a typical coal-fired thermal power station

7. -:Generation of Electricity:•
•
•
•
•
Prime mover coupled to
Alternator
Prime mover is driven by energy
obtained from various sources
such as
burning of fuel
pressure of water
Force of wind etc.
Fig. Fundamental of generation of Electricity

8. -:Thermal Power Plant:•
A generating station which converts heat energy of coal combustion
into electrical energy is known as a steam power station.
•
Steam is produced in the boiler by utilizing the heat of coal
combustion. The steam is then expanded in the steam turbine and is
condensed in a condenser to be fed into the boiler again. The steam
turbine drives the alternator which converts mechanical energy of the
turbine into electrical energy.

9. -:Basic Power Plant Cycle:-

10. -:WORKING OF STEAM POWER PLANT:Coal is burnt in a boiler ,which converts water into
steam.
• The steam is expanded in a turbine used to drive
alternator.
• The steam expanded is condensed in a condenser to
be feed into the boiler again.
• The entire arrangement of steam power plant can be
divided into.
•
a. fuel and ash plant.
b. air and fuel gas plant.
c. feed water and steam plant.
d. cooling water plant.

11. -:Main and Auxiliary Equipments:1. Coal handling plant
2. Stoker
3. Pulverizer
4.Boiler
5.Superheater
6.Eonomiser & Air preheater
7.Reheater
8.Deaerator
9.Condenser
10.Primary air fan
11.Turbine(prime mover)
12.Draft fan & chimney
13.Electo-static precipitator
14.Cooling tower
15.Ash handling plant
16.Electrical equipment
a. Generator
b. Transformers
c. Switch yard

12. -:Coal handling plant:-
•The
function of coal handling plant is automatic feeding of coal to the boiler
furnace.
• A thermal power plant burns enormous amounts of coal.
•A 200MW plant may require around 2000 tons of coal daily

13. Coal conveyor : This is a belt type of arrangement. With this coal is transported from
coal storage place in power plant to the place near by boiler.
Stoker : The coal which is brought near by boiler has to put in boiler furnace for
combustion. This stoker is a mechanical device for feeding coal to a furnace.
Pulverizer : The coal is put in the boiler after pulverization. For this pulverizer is used. A
pulverizer is a device for grinding coal for combustion in a furnace in a power plant. A
pulverizer is a device for grinding coal for combustion in a furnace in a power plant.
Pulverizing mills are further classified as:
1.Contact mill
2.Ball mill
3.Impact mill

14. -:Boiler:A boiler is closed vessel in which water is converted into steam by
utilising the heat of coal combustion.
Steam boilers are broadly classified into following two types:base on the
relative position of water and gases.
(a) Water tube boilers (b) Fire tube boilers
In a water tube boiler, water flows
through the tubes and the hot gases of
combustion flow over these tubes.
Water-tube boilers are used for highpressure boilers
Examples: cochron, Lancashire,
locomotive boiler.

15. In a fire tube boiler, the hot products of combustion pass through the
tubes surrounded by water.
• The heated water then rises into the steam drum. Here, saturated steam is
drawn off the top of the drum. The steam will reenter the furnace in
through a superheater in order to become superheated. Superheated
steam is used in driving turbines. Since water droplets can severely
damage turbine blades, steam is superheated to 730°F (390°C) or higher
in order to ensure that there is no water entrained in the steam.

16. -:Super heater:•
A device which removes last traces of moisture.
•
•
It helps in reduction in requirement of steam quantity.
steam being dry reduces the mechanical resistance of
turbine.
No corrosion at the turbine blades.
•

17. -:Economizer and Air Pre-heater:•
An economizer is a heat transfer device used for heating the feed water with
the help of hot flue gases before leaving the chimney.
•
It helps in improving the efficiency of the power plant.
•
Air preheater is a device which utilizes the waste heat of the flue gases leaving
the economizer to heat the air to be supplied to the boiler.

18. -:Reheater :Some of the heat of superheated
steam is used to rotate the turbine
where it loses some of its energy.
The steam after reheating is used
to rotate the second steam turbine
where the heat is converted to
mechanical
energy.
This
mechanical energy is used to run
the alternator, which is coupled to
turbine , there by generating
electrical energy.

19. -:DEAERATOR:•A steam generating boiler requires that the boiler feed water should be devoid
of air and other dissolved gases, particularly corrosive ones.
• In order to avoid corrosion of the metal, power station uses a Deaerator, for
the removal of air and other dissolved gases from the boiler feed water.
•A deaerator has a vertical, domed deaeration section mounted on top of a
horizontal cylindrical vessel which serves as a deaerated boiler feed water
storage tank.

20. -:Condenser:Which condenses the steam at the exhaust of turbine.
•It
creates a very low pressure at the exhaust of turbine, this
helps in converting heat energy of steam into mechanical
energy in the prime mover.
•The
condensed steam can be used as feed water to the
boiler.
•Classification of condenser
1.Jet condensers or contact condensers,
2. Surface condensers

21. Primary Air Fan:•
Air to blow the coal from the mill
to the boiler, called the primary
air, is supplied by a large fan
driven by a variable speed motor
•
When mixed with a stream of air
the powdered coal behaves more
like a gas than a solid
•
Primary air does two jobs –
heating the coal powder and
secondly lifting it into the furnace
through pipelines

22. -:Prime Mover (i.e. Turbine):A steam turbine is a mechanical device that extracts thermal energy from
pressurized steam, and converts it into mechanical energy.
The steam turbine is a form of heat engine that derives much of its
improvement in thermodynamic efficiency from the use of multiple stages in
the expansion of the steam, which results in a closer approach to the ideal
reversible expansion process.
About 86% of all electric generation in the world is by use of steam turbines.
BOILER
GENERATOR
STEAM TURBINE

23. -:Cooling Towers:Remove heat from the
water discharged from the
condenser so that the water
can be discharged to the
river or re circulated and
reused.
• Air can be circulated in the
cooling towers through
natural draft and
mechanical draft.
• Type of cooling tower
1. Wet cooling tower
2. Dry cooling tower
•

24. Induced Draught (ID) Fan
Chimney
•
•
Two induced draught fans draw
gases out of the boiler
•
The gas has already passed
through the air heaters and
precipitators before it has
reached these fans
•
The heat from the flue gases or
smoke is used in the air heaters
to heat up the primary and
secondary air
The chimney is 275 meters' high
and 50,000 tonnes of reinforced
concrete were used to make it
•
It consists of flues each of which
serve typically two or three boilers
(two units)

25. -:Electro-Static Precipitator:-
Top View of ESP Schematic Diagram

Side view of ESP Schematic Diagram
It is a device which removes dust or other finely divided particles from flue gases by
charging the particles inductively with an electric field, then attracting them to highly
charged collector plates. Also known as precipitator. The process depends on two
steps. In the first step the suspension passes through an electric discharge (corona
discharge) area where ionization of the gas occurs. The ions produced collide with
the suspended particles and confer on them an electric charge. The charged particles
drift toward an electrode of opposite sign and are deposited on the electrode where
their electric charge is neutralized. The phenomenon would be more correctly
designated as electrode position from the gas phase

27. -:COAL TRANSPORTATION SYATEM:


Source of coal = Piparwar Mines North Karanpur (Jharkhand)
Location = Near Ranchi
Means of transportation-Railway

Rout of ply=kalari-gawaroad,seonnogarmughalsarai,Allahabad,Kanpur,Aligarh,dadri-plant unloading area.

Distance = 1124 Km from kholori to dadri with electrified trak from
seonnogar.

Type of coal = F-grade (Washed),E grade(Raw)

C.V(calorific value)=3600-3800 kcal/kg.

Coal requirement = 13,000 MT/Day(04 rakes)

Type of wagon= 1.BOBR(bogy open rapid discharge)
= 2.Box-N(min 2 door on each said)

28. ASH HANDLING PLANT
The percentage of ash in coal is 5% in good quality coal & about 40% in poor
quality coal.
• Power plants generally use poor quality of coal , thus amount of ash produced
by it is quite large.
• A modern 1000MW plant produces about 4800 tons of ash daily.
• The stations use some conveyor arrangement to carry ash to dump sites.
•

29. -:Electrical Equipments:Alternator
An alternator is coupled to a steam turbine and converts mechanical
energy of the turbine into electrical energy.
It may be hydrogen or air cooled.
The necessary excitation is provided by means of main and pilot exciters
directly coupled to the alternator shaft.
Transformers
(a) main step-transformers, which steps-up generated voltage transmission
of power
(b) station transformers, general purpose
(c) auxiliary transformers, which supply to individual unit-auxiliaries.
Control Room and Switchyard :
The control room monitors the overall operation of the plant. It is
provided with controls for real and reactive power flow. It is provided
with safety relays and switchgears.

30. -:Coal Ash can be used in:•
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Construction of embankments and fills
Construction of road in sub-base
Manufacture of cement
Manufacture of bricks/blocks
Filling as flowable fill material
Agriculture as soil amendment/source of
essential plant nutrients

31. -:TRIPICAL DIAGRAM OP THERMAL POWER PLANT:-

32. Efficiency of Thermal Power Station or Plant
The overall efficiency of a thermal power station or plant varies from 20% to 26% and
it depends upon plant capacity.