Refrigeration systems operation

Experience shows that work must be done to transfer heat from a cold reservoir to a warm one. Refrigeration systems operate by removing heat from cold objects and expelling it to a warm room, and they require the operation of a compressor that performs work during the process. 

The most commonly used absorption-refrigeration system operates with water as the refrigerant and a lithium bromide solution as the absorbent. This system is obviously limited to refrigeration temperatures above the freezing point of water. It is treated in detail by Perry and Green.t For lower temperatures the usual system operates with ammonia as refrigerant and water as the solvent. 

It may be noted that refrigeration system operating on high-pressure ammonia is to be operated and maintained very carefully to prevent any accident. Capacity control facility to run the compressor at lower load if required. 

Conception of an Absorption Refrigerating System Operating at Low Enthalpy Sources... 

Therefore, conpared with cooling at 5°C, cooling to -20°C is 0.257/0.144 times as expensive, and cooling to -50°C is 0.426/0.144 times as expensive. This analysis assumes that the two refrigeration systems operate equally efficiently with respect to the reversible limit and that the major cost is the power to run the conpressors. 

METMYLAMINE. CH1NH2. Aluminum alloy equipment has been used in refrigeration systems operating with methylamine. See also Ref (Dp. 137. (2) p. 

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