Refrigeration system with integrated economizer/oil cooler

摘要

A refrigeration system for cooling air s disclosed. The system includes a substantially liquid refrigerant and an evaporator for transferring heat from the air to the substantially liquid refrigerant. The substantially liquid refrigerant becomes a low temperature, low pressure first superheated gas refrigerant. A compressor compresses the first superheated gas refrigerant into a high pressure, high temperature second further superheated gas refrigerant. A lubricant circuit supplies lubricant to the compressor, wherein a portion of the lubricant is mixed with the further superheated gas refrigerant. A condenser rejects heat from the second superheated gas refrigerant and forms a high pressure, low temperature sub-cooled liquid refrigerant. The condenser has an output stream. A metering device transforms the sub-cooled liquid refrigerant into the substantially liquid refrigerant for the evaporator. An economizer circuit provides an intermediate temperature and pressure economizer refrigerant flow to the compressor. The economizer refrigerant flow originates from the output stream of the condenser. The economizer circuit includes an economizer heat exchanger. The economizer heat exchanger includes paths for receiving and cooling the lubricant before returning to the compressor and the sub-cooled liquid refrigerant on route to the metering device, wherein the economizer refrigerant flow is a cooling medium in the heat exchanger.