brief description about all thermal working poer plant

1. THERMAL POWER PLANT
Presented by 1.F..God Brain

2. INTRODUCTION
• A Thermal Power Plant converts the heat energy
into electrical energy. Coal is burnt in a boiler
which converts water into steam. The expansion of
steam in turbine produces mechanical power which
drives the alternator coupled to the turbine.Thermal
Power Plants contribute maximum to the
generation of Power for any country . Thermal
Power Plants constitute 75.43% of the total
installed captive and non-captive power generation
in India . In thermal generating stations coal, oil,
natural gas etc. are employed as primary sources of
energy.

3. THERMAL
POWER PLANT
STEAM THERMAL
POWER PLANT DIESEL ENGINE
POWER PLANT
GAS TURBINE
POWER PLANT

6. • 1. solid fuel as coal
• 2. liquid fuel as oil
• 3. gaseous fuel as gas

7. •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

8. • The huge amount of coal is usually supplied through
railways. A railway siding line is taken into the power
station and the coal is delivered in the storage yard. The
coal is unloaded from the point of delivery by means of
wagon tippler. It is rack and pinion type. The coal is
taken from the unloading site to dead storage by belt
conveyors. The belt deliver the coal to 0 meter level &
further moves to transfer point. The transfer points are
used to transfer coal to the next belt. The belt elevates
the coal to breaker house. It consists of a rotary
machine, which rotates the coal and separates the light
dust from it through the action of gravity and transfer
this dust to reject bin house through belt.

9. Pulverising plant
• In modern thermal power plant , coal is
pulverised i.e. ground to dust like size and
carried to the furnace in a stream of hot air.
Pulverising is a means of exposing a large
surface area to the action of oxygen and
consequently helping combustion.
• Pulverising mills are further classified as:
1. Contact mill
2. Ball mill
3. Impact mill

10. • Primary air that carries the powdered coal
from mill to the furnace in only 20% with
additional air kown as secondary air in
addition to prime function of mixing burner
must also maintain stable ignition of fuel air
mix& control the flame shape & travel I the
furnace

11. Oil burner
Gas burner
The function of an oil burner are to mix fuel & air in proper
proportion and to prepare the fuel for combustion

14. Steam turbine
A steam turbine converts heat energy of steam into
mechanical energy and drives the generator. It uses the
principle that steam when issuing from a small opening
attains a high velocity. This velocity attained during
expansion depends on the initial and final heat content
of the steam. This difference b/w initial and final heat
content represents the heat energy converted into
kinetic energy.
These are of two types :-
Impulse turbine
Reaction turbine

16. Ash handling plant
The percentage of ash in coal varies from 5% in good quality
coal to about 40% in poor quality coal
Power plants generally use poor quality of coal , thus amount
of ash produced by it is pretty large
A modern 2000MW plant produces about 5000 tons of ash
daily
The stations use some conveyor arrangement to carry ash to
dump sites directly or for carrying and loading it to trucks and
wagons which transport it to the site of disposal

17. Boiler
• A boiler or steam generator is a closed vessel in which water
under pressure, is converted into steam.
• It is one of the major components of a thermal power plant
• Always designed to absorb maximum amount of heat released in
the process of combustion
Boilers are of two types-
1. Fire tube boiler
2. Water tube boiler

18. Boiler

19. Types of boilers
• Lamount boiler
• Loeffler boiler
• Benson boiler
• Velox boiler

20. Lamount boiler

21. Loeffler boiler

22. Benson boiler

23. Velox boiler

25. • Diesel power plants produce power in the
range of 2 to 50MW.
• They are used as standby sets for continuity of
supply such as hospitals , telephone
exchanges , radio station , cinema theatres
and industries (peak load).
• They are suitable for mobile power generation
and widely used in railways and ships.

27. • The air required for the
combustion of fuel
inside the diesel engine
cylinder is drawn
through the air filter.
The purpose of the filter
is to remove dust from
the incoming air.
• dry filter- may be made
of felt , wood or cloth.
• wet filter- oil bath is
used

28. • Fuel from the
storage tank is
pumped through a
filter into a smaller
tank called all day
tank . this tank
supplies the daily
requirements of the
diesel engine.

29. • The exhaust gases coming out of the engine is very
noisy. In order to reduce the noise a silencer is used.

30. • This circuit includes lubricating oil tank , oil
pump and oil cooler.
• The purpose of the lubrication system is to
reduce the wear of the engine moving parts
.part of the cylinder such as piston , shafts ,
valves must be lubricated.
• Lubrication also helps to cool the engine.

31. • Diesel engine used in diesel power plant is not
self starting . The engine is started from cold
condition whit the help of an air compressor.
Schematic diesel engine power plant

32. • The temperature of the burning fuel inside
the engine cylinder -15000C to 20000C. In
order to lower this temperature water is
circulated around the engine.
• The hot water leaving the jacket is passed
through the heat exchanger.
• The heat from the heat exchanger is carried
away by the raw water circulated through
the heat exchanger and is cooled in the
cooling tower

34. 1. Very simple design also simple
installation and occupies less space.
2. Limited cooling water requirement.
3. Smaller storage is needed for the fuel.
4. Layout of power plant is quite simple.
5. There is no problem of ash handling.
6. Less supervision required.

35. 1. High Maintenance ,lubrication cost and operating
cost.
2. Fuel cost is more, since in India diesel is costly.
3. The plant cost per kW is comparatively more.
4. The life of diesel power plant is small due to high
maintenance.
5. Noise is a serious problem in diesel power plant.
6. Diesel power plant cannot be constructed for
large scale.

37. Gas turbine power plant
Working principle :
Air is compressed(squeezed) to high pressure by a
compressor.
Then fuel and compressed air are mixed in a combustion
chamber and ignited.
Hot gases are given off, which spin the turbine wheels.

38. Description:
Gas turbines burn fuels such as oil, nature gas and
pulverized(powdered) coal.
Gas turbines have three main parts:
i) Air compressor
ii) Combustion chamber
iii) Turbine

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Air compressor:
The air compressor and turbine are mounted at
either end on a common shaft, with the combustion
chamber between them.
Gas turbines are not self starting. A starting motor
is used.
The air compressor sucks in air and compresses it,
thereby increasing its pressure.

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Combustion chamber:
In the combustion chamber, the compressed air
combines with fuel and the resulting mixture is
burnt.
The greater the pressure of air, the better the fuel air
mixture burns.
Modern gas turbines usually use liquid fuel, but they
may also use gaseous fuel, natural gas or gas
produced artificially by gasification of a solid fuel.

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Turbine:
Hot gases move through a multistage gas
turbine.
Like in steam turbine, the gas turbine also has
stationary and moving blades.
The stationary blades
guide the moving gases to the rotor blades
adjust its velocity.
The shaft of the turbine is coupled to a
generator.

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Open cycle gas turbine power plant

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Closed cycle gas turbine power plant

45. • Open cycle gas turbine with separate power
turbine
• Series flow gas turbine plant
• Parallel flow gas turbine plant
• Series flow plant with intercooled compression
• Series flow plant with reheat between turbine
stages
• Straight compound gas turbine plant

47. Open cycle gas turbine with separate power turbine

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Applications of gas turbine:
drive pumps, compressors and high speed cars.
aircraft and ships.
 Power generation (used for peak load and as stand-
by unit).

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Advantages of gas turbine power plant
 Storage of fuel requires less area and handling is
easy.
 The cost of maintenance is less.
 It is simple in construction. There is no need for
boiler, condenser and other accessories as in the case
of steam power plants.
 Cheaper fuel such as kerosene , paraffin, benzene
and powdered coal can be used which are cheaper
than petrol and diesel.
 Gas turbine plants can be used in water scarcity
areas.
 Less pollution and less water is required.

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Disadvantages of gas turbine power plant
 66% of the power developed is used to drive the
compressor. Therefore the gas turbine unit has a low
thermal efficiency.
 The running speed of gas turbine is in the range
of (40,000 to 100,000 rpm) and the operating
temperature is as high as 1100 – 12600C. For this
reason special metals and alloys have to be used for
the various parts of the turbine.
 High frequency noise from the compressor is
objectionable.