01 Introduction & Classification

7/25/2019 01 Introduction & Classification

1/86

AN INTRODUCTION TO

COMPRESSION EQUIPMENT

Eng./ Alaa E. Omar

7/2009
http://www.airgas.co.za/images/comvmy.JPG


2/86

An Introduction to Compression Equipment

From the earliestrecorded times, man

has used the air

around him to drive

his sailing ships andturn the blades of his

windmills.


3/86


Sailors and shipbuilders knewthrough countless ears of

trial and error how to cut and

set a sail for ma!imum

efficienc. "h the pressureand flow of air made one

shape better than another was

of little interest to them.


4/86


#he air was then made to $magicall open and close$

temple doors to the wonderments of the assembled rulers

and common people. %ere again the wh was no practicalvalue in the ees of these people, and therefore did not

particularl interest them.

&arl &gptian writings tell of 'riests using simple bellowsto compress air.

(t wasn)t until the earl to mid 17th centurthat manstarted to recogni*e the importance of the world around

him. +t this time his knowledge of the air around him

began to increase significantl.


5/86


#he !"emish A"chemist# $%n &e"mont,suspected from his stud from the vapors

given off b fermenting fruit uices that the air

was not composed of a single element, but

that it might be a compound or mi!ture ofsubstances.

&enr C%'endish, was among the first to

establish that air was indeed a mi!ture of at

least - chemicall different gases. (n theprocess, he discovered hdrogen.


6/86


Ro(ert )o"e, an &nglish phsicist in the laterhalf of the 7th centur, discovered the laws

governing the relationship between air

pressure to volume

#he great !rensh chemist, Antoine*%'oisier was set the proportions of o!gen

to nitrogen in air,and proved that the o!gen

content was essential to animal life.

A"e+%ndre Ch%r"esdiscovered the laws governing the

relationship of air pressure and temperature,


7/86


E'%n-e"ist% Torrice""iin about 0discovered the principle of the barometerb

being the first to measure the weight of the

atmosphere. (n an elegant e!periment, he

found it to be e1uivalent to a column ofmercur 0 inches high.


8/86


+ir, when compressed, represents apotential energ that can be used in a

tremendous variet of was.

an began to compress air and appl it

to a widespread and diverse uses about00 ears ago.

&arl compressors were steam driven, but in other respects

were essentiall the same as toda)s models, differing onl

in refinement of materials and tolerances.


9/86


.h%t is % compressor/


10/86


+ compressor is a device used to increase the pressureof acompressi("e0"uid.

In

"etpressure

2

3

Disch

%r-epressur

e

Su( %tmospheric

Atmospheric

&i-h "e'e"

Compressor


11/86


Compressor


12/86


#he fluid can be an compressible fluid3

either gas or vapor and can have a wide

molecular weight range.

.h%t does this me%n/


13/86


(t means that, to se"ectand desi-nof an compressor,the fundamental is a knowledge of the basic properties of

the gas or gases being compressed.

4

564

&dro-en

Ur%nium he+%0"uoride

Mo"ecu"%r7ei-htr%n-e


14/86


15/86


Compressor

Station

Compressor

Station

Production

32,000 Compressors

Processing

5,000 Compressors

Transmission & Storage

8,500 Compressors

Distribution

0 Compressors

Compressor

Station


16/86


App"ic%tions o0 compressors8

1,1 Ch%r-e -%s compressor8

4ompressors are commonl used in the plant to raise feed gas pressure to

operating conditions.

1,4 M%9eup -%s compressor8

4ompressors are also used to suppl reacting gas to sustain chemical reactions

1,5 Recc"e -%s compressor8

4ompressors are also used to reccle gas within a process

1,: O00-%s compressors8

an processes produce light gasses as bproducts known as an off5gas3

this is normall burned as fuel or wasted as flare.

+ compressor is commonl used to process off5gas and make it a valuableproduct.

1,6 Re0ri-er%tion compressors8

4ompressors pla a ke role in developing low temperature conditions.


17/86


For comparison, the different tpes of compressors canbe subdivided into two broad groups based on

compression mode.

#here are two basic modes6

Intermittent ,

Continuous,


18/86

E;ectorDn%mic

Intermittent 0"o

COMPRESSORS

Continuous 0"o


Positi'e disp"%cement

8adial

flow

i!ed

flow

+!ial

flow

8otar8eciprocating

%elical lobe

Straight lobe

Sliding vanes

i1uid piston

echanical

piston
http://../DiskTop/Compressor%20TC/C%20Presentation/C%20Course%20Chapters/RotaryTypes.ppthttp://../DiskTop/Compressor%20TC/C%20Presentation/C%20Course%20Chapters/PositiveDTypes.ppthttp://../DiskTop/Compressor%20TC/C%20Presentation/C%20Course%20Chapters/RotaryTypes.ppthttp://www.airgas.co.za/images/comvmy.JPGhttp://../DiskTop/Compressor%20TC/C%20Presentation/C%20Course%20Chapters/RotaryTypes.ppthttp://../DiskTop/Compressor%20TC/C%20Presentation/C%20Course%20Chapters/PositiveDTypes.ppthttp://../DiskTop/Compressor%20TC/C%20Presentation/C%20Course%20Chapters/RotaryTypes.ppt


19/86

E;ectorDn%mic

Intermittent 0"o

COMPRESSORS

Continuous 0"o



8adial

flow

i!ed

flow

+!ial

flow

8otar8eciprocating

%elical lobe

Straight lobe

Sliding vans

i1uid piston

echanica

l piston

Intermittent modeofcompression is cclic

in nature, in that a

specific 1uantit of

gas is ingested b

compressor, actedupon and discharged,

before the ccle is

repeated.

Continuous compressionmode is one in which the

gas is moved into

compressor, is acted

upon, moved through the

compressor anddischarged without

interruption of the flow at

an point in the process.
http://../DiskTop/Compressor%20TC/C%20Presentation/C%20Course%20Chapters/RotaryTypes.ppthttp://../DiskTop/Compressor%20TC/C%20Presentation/C%20Course%20Chapters/PositiveDTypes.ppthttp://../DiskTop/Compressor%20TC/C%20Presentation/C%20Course%20Chapters/RotaryTypes.ppthttp://../DiskTop/Compressor%20TC/C%20Presentation/C%20Course%20Chapters/RotaryTypes.ppthttp://../DiskTop/Compressor%20TC/C%20Presentation/C%20Course%20Chapters/RotaryTypes.ppthttp://www.airgas.co.za/images/comvmy.JPGhttp://../DiskTop/Compressor%20TC/C%20Presentation/C%20Course%20Chapters/RotaryTypes.ppthttp://../DiskTop/Compressor%20TC/C%20Presentation/C%20Course%20Chapters/PositiveDTypes.ppthttp://../DiskTop/Compressor%20TC/C%20Presentation/C%20Course%20Chapters/RotaryTypes.ppt


20/86

Intermittent 0"o

COMPRESSORS



#rap consecutive 1uantities of gas in

some tpe of enclosure, reduce the

volume thus increasing the pressure,

or carr it without volume change tothe discharge port and compress the

gas b back flow from the discharge

sstem, then push the compressed

gas out of the enclosure.
http://../DiskTop/Compressor%20TC/C%20Presentation/C%20Course%20Chapters/RotaryTypes.ppthttp://../DiskTop/Compressor%20TC/C%20Presentation/C%20Course%20Chapters/RotaryTypes.ppthttp://www.airgas.co.za/images/comvmy.JPGhttp://../DiskTop/Compressor%20TC/C%20Presentation/C%20Course%20Chapters/RotaryTypes.ppthttp://../DiskTop/Compressor%20TC/C%20Presentation/C%20Course%20Chapters/RotaryTypes.ppt


21/86

E;ectorDn%mic

Intermittent 0"o

COMPRESSORS

Continuous 0"o



8adial

flow

i!ed

flow

+!ial

flow

8otar8eciprocating

%elical lobe

Straight lobe

Sliding vans

i1uid piston

echanica

l piston

4ompress the gas b themechanical action of rapidl

rotating impellers or bladed

rotor that impact velocit to

the gas then convert it into

pressure in stationardiffusers or blades to the

flowing gas


22/86


2

20

200

02 0 0- 0: 0

ultistage

8eciprocating

Single stage

8ecip.

!"o r%te


23/86


62 >2 72 ?2 @2 122 112 142

>2

?2

122

142

1:2

Percent !"o

Pe

rcentPressure

R%tio

or&e%d

'ositive

;isplacement

4ompressors

+!ial5Flow

4ompressor

4entrifugal

4ompressors

;esign 'oint

ener%" Per0orm%nce Cur'e


24/86


25/86


Intermittent mode compressorsReciproc%tin- compressors


26/86



(t is a piston and

clinder device with


27/86



;eliver is usuall to a receiver.

#he receiver is effectivel a store of

energ used to drive


28/86



"hen a single clinder

is used or when multiple

clinders on a commonframe are connected in

parallel, the

arrangement is referred

to as a single-stagecompressor.


29/86



"hen multiple clinders

on a common frame are

connected in series,usuall through a cooler,

the arrangement is

referred to as a

multistage compressor.


30/86


31/86



;ue to their si*e and the

vibrations caused, the

re1uire large foundationsand ma not be suitable

where noise emissions are

an issue.

>evertheless, the are the most energ efficient, both at fulland part loads.


32/86



(t is generall in the lower

flow end of the compressor

spectrum. (nlet flows rangefrom less than 00to

appro!imatel 0,000 cfm/

clinder.

(t is particularl well suited for high5pressureservice.

#he reciprocating compressor is one of the most efficient of

all the compressors.


33/86

E;ectorDn%mic

Intermittent 0"o

COMPRESSORS

Continuous 0"o



8adial

flow

i!ed

flow

+!ial

flow

8otar8eciprocating

%elical lobe

Straight lobe

Sliding vanes

i1uid piston

echanical

piston


34/86


Intermittent mode compressorsRot%r Compressors

(t consists of a single rotor

mounted eccentricall in a

clinder slightl larger than

the rotor.

S"idin- $%ne Compressors

#he rotor has a series ofradial slots, which hold a set

of vanes.


35/86



#he vanes are free to move

radiall within the rotor slots.

S"idin- $%ne Compressors

#he maintain contact with

the clinder wall b

centrifugal force generatedas the rotor turns.


36/86

E;ectorDn%mic

Intermittent 0"o

COMPRESSORS

Continuous 0"o



8adial

flow

i!ed

flow

+!ial

flow

8otar8eciprocating

%elical lobe

Straight lobe

Sliding vanes

i1uid piston

echanical

piston


37/86



*iquid Piston Compressors

(t performs its compression

b use of li1uid ring acting

as a piston.

#he single rotor is located

eccentricall inside a

clinder or stator.


38/86

E;ectorDn%mic

Intermittent 0"o

COMPRESSORS

Continuous 0"o



8adial

flow

i!ed

flow

+!ial

flow

8otar8eciprocating

%elical lobe

Straight lobe

Sliding vans

i1uid piston

echanical

piston


39/86



&e"ic%" *o(e or Scre Compressors


40/86





41/86




Oi" in;ected Oi" !ree


42/86


Intermittent mode compressors

Rot%r Compressors


Screw


43/86



Rot%r Compressors


@ariable output and variable

speed drives are usuall available

from most suppliers.

?il (nected


44/86



Rot%r Compressors


4arr the same benefits as oil

inected screw compressors but

compress in two stages and have

no lubricant in contact with the

gas during its passage through

the compressor.

?il free


45/86



Rot%r Compressors


"ater inected screw

compressors are also available

where oil free air is re1uired.

?il free


46/86

E;ectorDn%mic

Intermittent 0"o

COMPRESSORS

Continuous 0"o



8adial

flow

i!ed

flow

+!ial

flow

8otar8eciprocating

%elical lobe

Straight lobe

Sliding vans

i1uid piston

echanical

piston


47/86



Rot%r Compressors

Str%i-ht *o(e Compressors

#he are commonl called

blowers, and the are low5pressure machines.

#he feature uni1ue to these

compressors is that the machines

do not compress the gas

internall as do most of the other

rotaries.


48/86



Rot%r Compressors


#he straight lobe compressor

uses two rotors, which inter5meshas the rotate.


49/86



Rot%r Compressors


#he features rotar compressors

have in common are6The imp%rt ener- to the -%s (ein-

compressed ( % o0 %n input sh%0t

mo'in- % sin-"e or mu"tip"e rot%tin-

e"ements,

The per0orm the compression in %n

intermittent mode,

The do not use in"et %nd disch%r-e

'%"'es,


50/86



Rot%r Compressors



51/86


52/86


Continuous compression compressors

E;ectors

#he eector can first be identified as having no moving parts .

it is used primaril for that feature as it is not as efficient as

most of the mechanical compressors.


53/86



E;ectors

#he eector is operated directl b a motive gas or vapor

source. +ir and steam are probabl the two most common of

motive gases.


54/86



E;ectors

#he eector uses a no**le to accelerate the motive gas into

the suction chamber where the gas to be compressed is

admitted at right angles to the motive gas direction.


55/86



E;ectors

(n the suction chamber, also referred to as the mi!ture

moves into a diffuser where the high velocit gas is graduall

decelerated and increased in pressure.


56/86



E;ectors

#he eector is widel used as a vacuum pump, where it is

staged when re1uired to achieve deeper vacuum levels.


57/86


58/86


59/86



E;ectors

#he eector is one of the few compressors immune to li1uid

carrover in the suction gas.


60/86

E;ectorDn%mic

Intermittent 0"o

COMPRESSORS

Continuous 0"o



8adial

flow

i!ed

flow

+!ial

flow

8otar8eciprocating

%elical lobe

Straight lobe

Sliding vans

i1uid piston

echanical

piston


61/86



Dn%mic compressors

(n dnamic compressors energ is transferred from a moving

set of blades to the gas.

Aecause of the dnamic nature of these compressors, the

densit and molecular weight have an influence on the

amount of pressure the compressor can generate.

#he energ takes the form of velocit and pressure in therotating element, with further pressure conversion taking

place in the stationar elements.


62/86



Dn%mic compressors

#he dnamic compressors are further subdivided into three

categories, based primaril on the direction of flow through

the machine.#hese are radial, a!ialand mi!edflow.


63/86

E;ectorDn%mic

Intermittent 0"o

COMPRESSORS

Continuous 0"o



8adial

flow

i!ed

flow

+!ial

flow

8otar8eciprocating

%elical lobe

Straight lobe

Sliding vans

i1uid piston

echanical

piston


64/86



Dn%mic compressors

R%di%" 0"o or centri0u-%" compressor


65/86



Dn%mic compressors


(t is a widel used compressor and is

probabl second onl to the reciprocatingcompressor in usage in the process

industries.

#he compressor uses an impeller consisting

of radial or backward5leaning blades and afront and rear shroud.


66/86



Dn%mic compressors


#he front shroud is optionall rotating or

stationar depending on the specific design.

+s the impeller rotates gas is moved between

the rotating blades from the area near the

shaft and radiall outward to discharge into a

stationar section, called a diffuser.


67/86


68/86


69/86



Dn%mic compressors


+nother feature of the centrifugal is its abilit

to admit or e!tract flow to or from the mainflow stream, at relativel close pressure

intervals, b means of strategicall located

no**les.
http://www.airgas.co.za/images/comvmy.JPGhttp://www.airgas.co.za/images/comvmy.JPG


70/86



Dn%mic compressors

)"oer8(s a single stage centrifugal fan

App"ic%tions8

Single5stage blowers are

preferred for high volume,

low pressure applications.


71/86

E;ectorDn%mic

Intermittent 0"o

COMPRESSORS

Continuous 0"o



8adial

flow

i!ed

flow

+!ial

flow

8otar8eciprocating

%elical lobe

Straight lobe

Sliding vans

i1uid piston

echanical

piston
http://../DiskTop/Compressor%20TC/C%20Presentation/C%20Course%20Chapters/RotaryTypes.ppthttp://../DiskTop/Compressor%20TC/C%20Presentation/C%20Course%20Chapters/PositiveDTypes.ppthttp://../DiskTop/Compressor%20TC/C%20Presentation/C%20Course%20Chapters/RotaryTypes.ppthttp://www.airgas.co.za/images/comvmy.JPGhttp://../DiskTop/Compressor%20TC/C%20Presentation/C%20Course%20Chapters/RotaryTypes.ppthttp://../DiskTop/Compressor%20TC/C%20Presentation/C%20Course%20Chapters/PositiveDTypes.ppthttp://../DiskTop/Compressor%20TC/C%20Presentation/C%20Course%20Chapters/RotaryTypes.ppthttp://www.airgas.co.za/images/comvmy.JPG


72/86



Dn%mic compressors

A+i%" compressors


73/86


74/86



Dn%mic compressors

+ gas particle passing through the machine

alternatel moves through a stationar row,then a rotor row, then another stationar

blades row, until it completes the total gas

path.

'air of rotating and stationar blades rowsdefines a stage.

A+i%" compressors


75/86


76/86



Dn%mic compressors

?ne common arrangement has the energ

transfer arranged to provide :0B of thepressure rise in the rotating row and the other

:0B in the stationar row. #his design is

referred to as :0B reaction.

+!ial compressors are smaller and aresignificant more efficient than centrifugal

compressors when a comparison is made at

an e1uivalent flow rating.

A+i%" compressors


77/86



Dn%mic compressors

#he a!ial compressor, because of a low

pressure rise per stage, is e!clusivelmanufactured as a multistage machine.

A+i%" compressors

+!ial compressors are an integral part of

large gas turbines where the pressure ratios

normall are much higher. (n gas turbineservice, discharge pressures up to :0 psiare

utili*ed.


78/86



Dn%mic compressors

!%ns

Single5stage a!ial compressors or a!ial flow fans,

App"ic%tions8

used in applications in

which large volumes of

compressed air or gasare re1uired.


79/86

E;ectorDn%mic

Intermittent 0"o

COMPRESSORS

Continuous 0"o



8adial

flow

i!ed

flow

+!ial

flow

8otar8eciprocating

%elical lobe

Straight lobe

Sliding vans

i1uid piston

echanical

piston
http://../DiskTop/Compressor%20TC/C%20Presentation/C%20Course%20Chapters/RotaryTypes.ppthttp://../DiskTop/Compressor%20TC/C%20Presentation/C%20Course%20Chapters/RotaryTypes.ppt


80/86



Dn%mic compressors

Mi+ed 0"o compressor


81/86


82/86



Dn%mic compressors

Mi+ed 0"o compressor

#he compressor si*e is fle!ible

and covers the centrifugalcompressor flow range, generall

favoring the higher flow rates.

#he head per stage is lower than available in the centrifugal.


83/86


Compressors

PositiveDisplacement

Dynamic

PistonReciprocating

Rotary Centrifugal Axial

Conc"usion


84/86


85/86


Conc"usion


86/86


Documents

01 Introduction & Classification