The document describes the components and process of a coal-based thermal power plant. The plant uses a modified Rankine cycle to convert heat from burning coal into mechanical work through a steam turbine, then into electrical energy using a generator. It lists and explains the key components involved in coal handling, heating water to produce steam, generating power from steam, and managing waste ash.

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3. Coal based thermal power
plant works on the principal
of Modified Rankine Cycle.
The Rankine cycle is a
model that is used to predict
the performance of steam
engines. The Rankine cycle
is an idealised
thermodynamic cycle of a
heat engine that converts
heat into mechanical work.
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4. Coal handling plant
 Economiser
 Air Pre heater
Re heater
 Steam turbines
Condenser
 Boiler
Cooling tower
Ash handling
 Generator
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5. : In coal-fired power stations, the raw feed
coal from the coal storage area is first crushed into small pieces and then
conveyed to the coal feed hoppers at the boilers.
: they are used in order to remove the excess moisture from coal
mainly wetted during transport.
 : coal which is brought may contain iron
particles. The iron particles may include bolts, nuts wire fish plates etc.
so these are unwanted and so are removed with the help of magnetic
separators.
These are detect the presence of any ferrous and non-ferrous
metal in the coal and sends a signal to a relay which closes to seize the
movement of belt until the metal is removed. It basically consists of a
transmitter and a receiver
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6. To SSTPS from gudla
via a single railway
track
Wagon
tippler
hoppers
Crusher
house
bunkers
Raw coal
feeders
Coal mills
(pulverization)
Boiler furnace ( tangential firing
of pulverized coal)

7.  Boiler is a combustion chamber
where water is heated at such
a temperature to achieve high
pressure steam .
 1) fire tube boiler
 2) water tube boiler
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8.  Flue gases coming out of the boiler carry lot of heat. An
economizer extracts a part of this heat from flue gases and uses it
for heating feed water. This use of economizer results in saving
coal consumption and higher boiler efficiency
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9. The heat carried out with the flue
gases coming out of economiser are further utilized
for preheating the air before supplying to the
combustion chamber. It is a necessary equipment for
supply of hot air for drying the coal in pulverized fuel
systems to facilitate grinding and satisfactory
combustion of fuel in the furnace
 Power plant furnaces may have a re-heater
section containing tubes heated by hot flue gases
outside the tubes. Exhaust steam from the high
pressure turbine is rerouted to go inside the re-heater
tubes to pickup more energy to go drive intermediate
or lower pressure turbines.
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10.  A steam turbine is a device that extracts thermal energy from
pressurized steam and uses it to do mechanical work on a rotating
output shaft . Because the turbine generates rotary motion, it is
particularly suited to be used to drive an electrical generator.
Steam
HPT HPT IPT IPT LPT LPT
Generator
Super
Heater
RH
Steam
Shaft
Condenser
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11. Generator or Alternator is the electrical end of a turbo-generator
set. It is generally known as the piece of equipment that converts
the mechanical energy of turbine into electricity. The generation
of electricity is based on the principle of electromagnetic
induction. Generally three phase synchronous generator is used
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14.  The disposal of ash from a large capacity power station is of same
importance as ash is produced in large quantities. Ash handling
is a major problem.
While barrows are used for this. The ash is
collected directly through the ash outlet door from the boiler
into the container from manually.
Mechanical equipment is used for ash
disposal, mainly bucket elevator, belt conveyer. Ash generated is
20% in the form of bottom ash and next 80% through flue gases,
so called Fly ash and collected in ESP.
The dust particles are ionized and
attracted by charged electrodes. The electrodes are maintained at
60KV.Hammering is done to the plates so that fly ash comes
down and collect at the bottom.
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16. They can respond to rapidly changing loads
without difficulty
A portion of the steam generated can be used as a
process steam in different industries
Steam engines and turbines can work under 25 %
of overload continuously
Fuel used is cheaper
Cheaper in production cost in comparison with
that of diesel power stations
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17. Maintenance and operating costs are high
 Long time required for erection and putting
into action
A large quantity of water is required
Great difficulty experienced in coal handling
 Presence of troubles due to smoke and heat in the
plant
Unavailability of good quality coal
Maximum of heat energy lost
 Problem of ash removing
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