The document discusses various components and processes involved in a steam power plant. It describes different types of boilers used including water tube, fire tube, and supercritical boilers. It also discusses coal handling systems, pulverizers, fluidized bed combustion, ash handling, dust collection, condensers, cooling towers/ponds, turbine governing, regeneration/reheating, plant operation and maintenance, heat balance/efficiency calculations, and factors considered for site selection of a steam power plant.

1. jahangirabad institute of technology

2. Steam power plant
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3. General layout of steam power
plant
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4. Power plant boilers
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Boilers
Water tube Fire tube
Babcock
Wilcox
Benson
boiler
Critical
pressure
Cochran
boiler
Lancashire
boiler
Locomotive
boiler

5. Super critical boilers.
In all modern power plants, high pressure boilers (> 100 bar)
are universally used. These high pressure boiler is known
supercritical boiler.
Types of super critical boilers are as follows.
La Mont boiler
Benson boiler
Loeffler boiler
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6. La Mont boiler
A forced circulation boiler was first introduced in 1925 by La Mont. The
arrangement of water circulation and different components are shown in
Fig.
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7. Loeffler boiler
The major difficulty experienced in Benson boiler is the
deposition of salt and sediment on the inner surfaces of
the water tubes.
The difficulty was solved in Loeffler boiler by preventing
the flow of water into the boiler tubes.
Most of the steam is generated outside from the feed water
using part of the superheated steam coming out from the
boiler.
This boiler can carry higher salt concentration than any
other type and is more compact than
indirectly heated boilers having natural circulation.
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8. Boilers mountings and
accessories
Mounting:- Boiler mountings are used to run a boiler in a
safe way ex: safety valve, Water level indicators etc.
accessories:-Boiler accessories are used to improve the
efficiency of a boiler ex: economizer, air pre-heater etc
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9. Coal handling
Coal delivery equipment is one of the major components of
plant cost. The various steps involved in coal handling are
as follows,
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Coal
Delivery
Unloadin
g
Transfer
Outdoor
Storage
Covered
Storage
In Plant
Handling
Weighing
&Measuri
ng
Furnace

10. pulverizers and coal burners
 A pulverized coal burner should satisfy the following requirements:
 It should mix the coal and primary air thoroughly and should bring this
mixture before it enters the furnace in contact with additional air known as
secondary air to create sufficient turbulence.
 It should deliver and air to the furnace in right proportions and should
maintain stable ignition of coal air mixture and control flame shape and
travel in the furnace.
 Coal air mixture should move away from the burner at a rate equal to flame
front travel in
 order to avoid flash back into the burner.
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11. Fluidized bed combustion
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 Burning of pulverised coal has some
problems such as particle size of coal
used in pulverised firing is limited to
70-100 microns.
 the generation of high temp. about
(1650 C) in the furnace creates
number of problems like slag
formation on super heater.
 Fluidized Bed combustion system can
burn any fuel including low grade
coals (even containing 70% ash), oil,
gas or municipal waste.
tubes
Air
Flue
gases
stea
m
Fuel and
dolomite
water
Distributer
plate
tube
s
ash

12. Ash handling system
 A large quantity of ash is, produced in steam power plants using coal.
Ash produced in about 10 to 20% of the total coal burnt in the
furnace.
 It is desirable to quench the ash before handling due to following
reasons:
1. Quenching reduces the temperature of ash.
2. It reduces the corrosive action of ash.
3. Ash forms clinkers by fusing in large lumps and by quenching
clinkers will disintegrate.
4. Quenching reduces the dust accompanying the ash.
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13. The commonly used ash handling
systems
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(i) Hydraulic system
(ii) pneumatic system
(iii) Mechanical system.

14. Dust collection system
 In coal fed furnaces the
products of combustion contain
particles of solid matter
floating in suspension.
 This may be smoke or dust.
 In spreader stokers and
pulverised coal fired furnaces
the coal is burnt in suspension
and due to this dust in the form
of fly ash is produced. The size
of dust particles is designated
in microns (1 μ =0.001 mm).
The disposal smoke to the
atmosphere is not desirable due
to the following reasons
 A smoky atmosphere is less
healthful than smoke free air.
 Smoke is produced due to
incomplete combustion of coal.
 In a smoky atmosphere lower
standards of cleanliness are
prevalent.
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15. condenser and cooling towers and
cooling ponds
Condenser:- A closed vessel in which steam is condensed
by abstracting the heat and where the pressure is
maintained below atmospheric pressure is known as a
condenser.
Steam condenser are of two types:
1. Surface condenser.
2. Jet condenser.
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16. Types of condenser
Surface type Jet type
 In surface condensers there is
no direct contact between the
steam and cooling water and
the condensate can be re-used
in the boiler.
 In such condenser even impure
water can be used for cooling
purpose whereas the cooling
water must be pure in jet
condensers.
 In jet condensers the exhaust
steam and cooling water come
in direct contact with each
other.
 The temperature of cooling
water and the condensate is
same when leaving the
condensers.
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17. Governing of turbine
Governing of steam turbine means to regulate the supply
of steam to the turbine in order to maintain speed of
rotation sensibly constant under varying load conditions.
(i) Bypass governing.
(ii) Nozzle control governing.
(iii) Throttle governing.
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18. Regeneration and reheating
Regeneration Re heating
 In regeneration cycle, the heat
energy from the exhaust flue
gases is transferred to the
compressed air before it enters
the combustion chamber.
 In reheat cycle, the combustion
gases are not expanded in one
turbine only but in two
turbines.
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19. Operation and maintenance of
steam power plant
 Application of control power illuminates all the malfunctions lights.
 Operate ‘Reset switch’ to reset malfunctions circuits: By doing so, malfunction
lights go off and all control devices assume the condition for starting.
 Operate “Start” switch to initiate starting sequence. By doing this, lube oil pump and
cooling fan start. If there are separate switch for these, operate these.
 When lube oil reaches a preset pressure, the starter is energized and cranking of the
engine begins.
 With the cranking of starting of starter, the engine and exhausts ducts are purged of
any combustible gases that might be present.
 During the cranking cycle, the fuel boost pump is used and operated to increase fuel
pressure.
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20. Heat balance and Efficiency
this is a useful method to watch the performance of the
diesel power plant.
Among all the heat supplied to an engine only part of it is
converted into useful work.
The heat balance of an engine depends on a number of
factors among which loads are primary importance.
Quantity of cooling water and its outlet and inlet
temperatures.
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21. Site selection of a steam power
plant
These are the factors effecting the selection of power plant
Availability of water.
Distance from populated area.
Distance from load center.
Accessibility to site.
Waste disposal.
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