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abbasi
18-12-2004, 09:16 AM
can any body give me comparison of the two systems?

plz explain in both financial and technical terms




Regards

Tejbir Singh
18-12-2004, 10:05 AM
can any body give me comparison of the two systems?

I hope you are talking about aircondition units.

Cost wise there is huge difference if you compare the compression and absorption type chiller system.(in India Reciprocating type unit of say 100TR costs Rs.1000000.00 and Aborption unit of same capacity will cost Rs.2400000.00)

technically both systems are totally apart compression type require another deivce or drive to drive the compressor.

where as absorption type needs heat source only it may waste heat of foundries, biogas, CNG or steam or even hot water of Elecricity generators( og more than 500MW)

compresion units works with refrigerant only where as absorption units works with refrigerant and absorber.

dunham bush's web site explains all about absorption

Tejbir Singh :D

Tejbir Singh

botrous
02-01-2005, 11:20 PM
Technicly there are huge differences between the 2 systems :
A compression cycle uses : a compressor (mechanical action is needed) a condenser , an evaporator and an expansion device . . .
The refrigerant used in compression cycles in a full chemical composite that his proprieties varies according to his pressure and tempreture , the cycle takes advance of those propreties to produce cold (no such thing called cold , the cold is the substruction of heat from a place ).

An absorption cycle uses a generator usually need power or a source of heat to heat a solution of Ammonia NH3 or Lithium Bromire L2Br and have a condenser , evaporator and an absorber.
So the refrigerant used here is a water + additives (NH3) wihch makes the solution that will produce cold according to the evolution of it's propreties in the cycle .

Ammonia is very toxic and isn't advised to be used in residence and commerce ... Lithium Bromire isn't toxic , it is used nowadays in the minibars in the hotels rooms (ex: Electrolux minibars) .

Financially an absorption system costs more than a compression one maybe because it is rarely manufactured comparing to the compression systems

Comfort :
Absorption systems are noise free
Compression systems have noises

Servicing :
Absorption can be considered as a static system that rarely needs to be serviced and maintained.
Compression is a dynamic system with moving parts which cause it to need maintenance and servicing periodicly.

Hope the information were useful for u :D

ice_cool
11-11-2008, 10:57 AM
we should compare compression,absorption & thermo-electric. compressor system is for home & commercial cooling system. absorption is for industrial cooling system. thermo-electric is for small fridge.

yangchenchen
13-11-2008, 04:27 AM
compressor system is for home and commercial cooling system?
It is not correct, compression is also for industrial cooling system, and is used widely.

The MG Pony
17-11-2008, 05:37 AM
compressor system is for home and commercial cooling system?
It is not correct, compression is also for industrial cooling system, and is used widely.

*Points up* 2004 you're 4 (Closer to 5) years late ;)

Sridhar1312
18-12-2008, 03:40 AM
Compression uses electrical energy Absorption uses heat energy(it can be steam, direct fired, Natural gas etc)

Absorption in todays context is used where you have surplus steam similar to Paper mills where they have Co generation power plants or where easy availabilty of gaseous fuel like LPG or LNG is available.
Absorption is basically combination of heat & Mass transfer and has very few moving parts and will be bulkier compared to compression system.
Heat rejection factor in Compression system is in the order of 1.2 for water cooled system and for Absorption it 1.8 and needs bigger cooling tower compared to Compression system

abbasi
02-02-2009, 09:28 AM
i know the technical details, i just want financial comparison/feasibility

Brian_UK
02-02-2009, 09:12 PM
I would have thought that after four and a bit years you might have the answers by now ;)

Sridhar1312
06-02-2009, 04:50 PM
Can you give capacity and fuel source(steam / diesel / CNG /LPG) for Absorption to enable make a comparison.
In any case Absorption is feasible only where surplus steam is available.
For 100 TR Screw Chiller will cost Indian Rs.1800000 , where as Steam fired absorption shall be Rs.2500000 and you need to add boiler cost if captive generation need to be made.Trust this will give you a fair idea.
As per BEE(Bureau of Energy Efficiency) in their reccommendations suggest to use Vapor Absorption only where Steam is available in surplus typically in CO GEN Plants, Paper Mills where steam is used for process and will be available.

nh3wizard
06-02-2009, 09:26 PM
I would have thought that after four and a bit years you might have the answers by now ;)

:D:o:rolleyes::) My thoughts exactly, could have wrote a book on the subject.

Dial666
06-02-2009, 10:16 PM
I see its 4 year old but can somebody point in the direction of how an absorbers system works, many thanks