compressed air system in thermal power plant

8/13/2019 Compressed Air System in Thermal Power Plant

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26 December 2013 PMI Revision 00 1

COMPRESSEDAIR SYSTEM


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What is Compressed Air System It consists of compressor used to generate high

pressure air as per requirement of a TPS.

The compressor used in power plant is a two

staged reciprocating type. Two separate compressed air system namely

Instrument air system and Plant air system are

in use.

Suitable dryer is provided for making the

delivered air free from moisture for specific

application purpose.


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Necessity of Compressed Air Operating Electro pneumatic controllers,

pneumatic valves, Oil burner movement, Burner

tilt mechanism, pneumatic motors and devices

etc. in main plant

Operating MGR & CHP equipments

Pneumatic transportation of ash for DACS.

Cleaning purpose.


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Instrument Air Compressor basicstructure Instrument air compressors are of the double

acting horizontal cross head type of two

opposed cylinder. The compressors are driven

by electric motor through V belts The suction air filter is at the middle of the

cylinder so that air can enter at both ends of

the piston.


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Instrument Air Compressor basicstructure After compression the air passes through the

delivery valves to the Inter-cooler where the airis considerably cooled and enters the H.P.cylinder.

The entrapped air in HP side is compressed in a

similar manner as in L.P. Cylinder to therequired pressure and enters the headerconnected to the H.P. cylinders through thedelivery valves and then finally to the airreceiver.


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Reciprocating Compressor


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Air-Drying Unit Air contains moisture which tends to condense,

and causes trouble in operation of variousdevices by compressed air.

Air drying unit consists of dual absorptiontowers with embedded heaters for reactivation.

The absorption towers are adequately filled withspecially selected silica gel and activatedalumina.

While one tower is drying the air, the other toweris under reactivation.


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Service-Air Compressor Station air compressor is generally a slow speed

horizontal double acting double stage type and isarranged for belt drive

From the high pressure cylinder compressed air isled through water cooled " after cooler" which isprovided with inlet and outlet water connection and

a drain.


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Compressor outletinterconnection A moisture separator with a drain trap and a filter

are provided to remove moisture and dust particles

from the compressed air.

There is one interconnection between service airand instrument air headers just at the inlet of air

drying units.

This connection has been provided as an

emergency provision to meet the requirement of

instrument air in case of non-availability of

instrument Air Compressor.


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Problem encountered with compressed airsystem System leakage.

Loading unloading cycle.

Ambient temperature. Moisture in outlet. (in efficiency in dryer)


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THANK YOU

compressed air system in thermal power plant

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