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Comparison of Vapor Absorption System with Vapor Compression System

Comparison of Vapor Absorption System with Vapor Compression System

Comparison of Vapor Absorption System with Vapor Compression System can be done in 9 aspects, they are energy input, moving part, evaporator pressure, load variation, evaporator exit, coefficient of performance, capacity,refrigerant and lowest temperatures.
S.no
Aspect
Vapor Absorption System
Vapor Compression System
1Energy InputVapor absorption system takes in low grade energy such as waste heat from furnace, exhaust team or solar heat for its operations.Vapor compression system takes in high grade such as electrical or mechanical energy for its operation of compressor used in the cycle.
2Moving partIt uses a small pump as moving part, which is run by a small motor.It uses a compressor driven by an electric motor or engine.
3Evaporator pressureIt can operate with reduced evaporator pressure, with little decrease in refrigerant capacity.The refrigerant capacity decreases with lowered evaporator pressure.
4Load variationThe performance of vapor absorption system does not change with load variationThe performance of vapor compressing system is very poor at partial load.
5Evaporator exitIn vapor absorption system, the liquid refrigerantleaving the evaporator does not put any bad effect on the system except to reduce the refrigerant effect.In a vapor compression system, it is desirable to superheat vapor before leaving the evaporator, so no liquid can enter the compressor.
6Lowest temperatureSince water is used as refrigerant, thus the lowest temperature attained is above 0°C.With cascading, the temperature can be lowered upto -150°C or even less temperature.
7Coefficient of PerformanceThe COP of the system is poor.The COP of the system is excellent.
8CapacityIt can built in capacities well above 1000 TR.For a single compression system, it is not possible to have a system with more than 1000 TR capacity.
9RefrigerantWater or ammonia is used as refrigerant.Chloroflourocarbon, hydroflorocarbon and hydrochlorofluorocarbon are used in most of the systems.

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