Cascade cryogenic refrigeration system is a low-temperature refrigeration system which uses more than two refrigerants and combines them with heat exchangers (condenser evaporators) in more than two systems. For binary cascade refrigeration system chiller, it consists of two separate refrigeration systems. One is the high temperature system, the other is the low temperature system. The cryogenic system is used to cool the environmental laboratory, while the high-temperature system is used to cool the exhaust gas of the cryogenic system and condensate it at a lower temperature. This also achieves the purpose of reducing compression ratio and improving gas transmission coefficient.

The advantages of the industrial chiller for cascade cryogenic refrigeration system are the use of medium-pressure refrigerants suitable for high-temperature systems and high-pressure refrigerants suitable for low-temperature systems. The specific capacity of high pressure refrigerant gas at low temperature is much smaller than that of medium pressure refrigerant. Therefore, the refrigeration capacity of the same type of compressor for cascade refrigeration is several times larger than that of two-stage compression refrigeration at low temperature. The use of cascade refrigeration system water cooler can save a lot of investment and building area. Moreover, the high-pressure refrigerant operates at a low temperature with an inhalation pressure greater than or close to one atmosphere, and it does not often infiltrate into the system like a two-stage cryogenic system.

The cascade refrigeration system can be used for industrial water chillers, except that the user’s requirement varies greatly and the ambient temperature is above – 55 C. At present, there are more and more cold sources using cascade refrigeration system as cryogenic experimental equipment.