operation problems compressor.ppt

8/10/2019 Operation Problems Compressor.ppt

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Compressors & Drivers


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Compressor Types

Dynamic

Centrifugal

Ejector

Displacement

Positive Diplacement Issues

Control

Seals
http://www.chemeng.ca/maine.htmlhttp://www.chemeng.ca/mainf.htmlhttp://www.chemeng.ca/maine.html


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EJECTOR CENTRIFUGAL

DYNAMIC

ROTARY RECIPROCATING

DISPLACEMENT

COMPRESSORS

SUCTION

DISCHARGEMOTIVEFLUID


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EJECTOR CENTRIFUGAL

DYNAMIC


DISPLACEMENT

COMPRESSORS


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EJECTOR CENTRIFUGAL

DYNAMIC


DISPLACEMENT

COMPRESSORS


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EJECTOR CENTRIFUGAL

DYNAMIC


DISPLACEMENT

COMPRESSORS


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EJECTOR CENTRIFUGAL

DYNAMIC


DISPLACEMENT

COMPRESSORS


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EJECTOR CENTRIFUGAL

DYNAMIC


DISPLACEMENT

COMPRESSORS

Axial


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EJECTOR CENTRIFUGAL

DYNAMIC


DISPLACEMENT

COMPRESSORS


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EJECTOR CENTRIFUGAL

DYNAMIC


DISPLACEMENT

COMPRESSORS

SUCTION

DISCHARGE


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ESTIMATOR CHOICES


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Selection Chart


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ESTIMATOR - Compressor

Input


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Fluid Power Calculation Fluid Static Head -> approx. 0

Include Piping Frictional Losses of 10 psi per

segment between equipment. Exchanger Losses per simulation assumptions

Control Valve losses (15 psi for our 500 psig

system - but eliminate if possible?).

Fluid Flow

Efficiency (75% to 80%)


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PRO II OutputUNIT 8, 'COMPRESSOR'

FEEDS LP-RECYCLE

PRODUCTS VAPOR HP-RECYCLE

OPERATING CONDITIONS

INLET ISENTROPIC OUTLET

----------- ----------- -----------

TEMPERATURE, C 39.83 254.14 278.88

PRESSURE, KPA 1190.00 39100.00 39100.00

CP/CV 1.2533 1.2627 ACT VAP RATE, M3/SEC

0.1042

ADIABATIC EFF, PERCENT 80.0000

HEAD, M

ADIABATIC 30028.91

POLYTROPIC 31045.39

ACTUAL 37536.13

WORK, KW

THEORETICAL 542.63

POLYTROPIC 561.00

Seals Normally

Limited to 350 F(180 C)


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Compression Ratio P2 / P1 (absolute pressures)

Not required in our calcs for cost but if

excessive are an indication that a multistagecompressor would be required (usuallyconfirmed by outlet temperature).


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Centrifugal

Compressors and FansPerformance & Controls

Diff

Press

Inlet Volumetric Flow Rate

Surge Okay


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Centrifugal - Control For constant discharge pressure systems

(most common). Variations in process flow

rate are controlled through the inlet valve

Inlet Vane Changes

The Flow vs DP

Curve of the

Compressor


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Centrifugal - Control

Diff

Press


Open Inlet Valve

Closing Inlet Valve

Surge Line


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Centrifugal - ControlAt the point where further restriction in the

inlet valve would cause surging other controls

are required. Usually

Blow Off

Recirculation


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Centrifugal - Control Blow Off

Blow Off Valve

Disch

Inlet

Blow Off


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Centrifugal - Control Recirculation

Disch

Inlet


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Centrifugal - ControlVariable SpeedUsed on the smaller compressors for

energy efficiency

Diff

Press


High RPM

Low RPM


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Drives For Pumps andCompressors


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Drives For Pumps and

Compressors T.E.F.C.


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TEFC

Air Flow

seal

bearing


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Electric Drives Enclosures

protected from outside environment

allows free ambient room air to cool windingsdrip proof guarded

weather protected

Totally Enclosed Fan Cooled

TEFC most common motor used - isolated fromthe free exchange of outside air

Explosion Proof - designed to isolatesurroundings from ignition sources such as

sparking or high temperatures inside the motor


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Electrical Area Classification Performed by electrical and process engineers

Process of classification

identifies processes that have explosion potential flammable liquids, gases, vapors, combustible dust, or

ignitable fibers or flyings

based on flash point, operating temperature etc.

Identifies distances from process that are safe

identifies equipment and instrumentationenclosure requirements

i.e. Explosion proof


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Our Compressor What composition we have going through

compressor?

Is the material a fire/explosion hazard (operatedabove its flash point) ?

Do we have an explosion potential if it leaks out ofcompressor?

What drive type should we choose?

operation problems compressor.ppt

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