Modular CO2 refrigeration system

摘要

A cascade CO2 refrigeration system includes a medium temperature loop for circulating a medium refrigerant and a low temperature loop for circulating a CO2 refrigerant. The medium temperature loop includes a heat exchanger having a first side and a second side. The first side evaporates the medium temperature refrigerant. The low temperature loop includes a discharge header for circulating the CO2 refrigerant through the second side of the heat exchanger to condense the CO2 refrigerant, a liquid-vapor separator collects liquid CO2 refrigerant and directs vapor CO2 refrigerant to the second side of the heat exchanger. A liquid CO2 supply header receives liquid CO2 refrigerant from the liquid-vapor separator. Medium temperature loads receive liquid CO2 refrigerant from the liquid supply header for use as a liquid coolant at a medium temperature. An expansion device expands liquid CO2 refrigerant from the liquid supply header into a low temperature liquid-vapor mixture for use by the low temperature loads.

主权项

1. A cascade CO2 refrigeration system, comprising:
a medium temperature loop for circulating a medium temperature refrigerant, the medium temperature loop including a heat exchanger having a first side and a second side, the first side configured to evaporate the medium temperature refrigerant and a medium temperature compressor, a condenser, and a medium temperature expansion device packaged in a modular unit with the heat exchanger; a low temperature loop for circulating a CO2 refrigerant, the low temperature loop including: a low temperature discharge header configured to circulate the CO2 refrigerant through the second side of the heat exchanger, the second side of the heat exchanger configured to condense the CO2 refrigerant; a liquid-vapor separator configured to collect liquid CO2 refrigerant and to direct vapor CO2 refrigerant to the second side of the heat exchanger; a pump; a liquid CO2 refrigerant supply header; a plurality of medium temperature loads configured to receive liquid CO2 refrigerant from the liquid CO2 refrigerant supply header for use as a liquid coolant in the medium temperature loads and to discharge the CO2 refrigerant directly to the liquid-vapor separator; a plurality of low temperature loads; a low temperature expansion device associated with the low temperature loads and configured to expand the liquid CO2 refrigerant from the liquid CO2 refrigerant supply header into vapor CO2 refrigerant for use as a vapor refrigerant by the low temperature loads.