Non-compression cascade refrigeration system for closed refrigerated spaces

摘要

A non-compression cascade refrigeration system 30 for refrigerating a closed refrigerated space includes a cascade condenser 34 in heat exchange relationship with a primary evaporator 24, a cascade evaporator 28 positioned in the refrigerated space 40 and a liquid and vapor separator 42. A first coolant delivery conduit 44 delivers liquid coolant from the cascade condenser 34 to the separator 42 which then provides the coolant through a second coolant delivery conduit 46 to the cascade evaporator 28 for cooling the refrigerated space 40. A first coolant return conduit 50 returns the coolant from the cascade evaporator 28 to the separator 42 where the return coolant is separated into liquid and gaseous coolant, such that the liquid coolant is directed to the second delivery conduit 46 for reuse in the cascade evaporator 28 and the gaseous coolant is directed to a second coolant return conduit 52 and returned to the cascade condenser 34.