Combined refrigeration system with a liquid pre-cooling heat exchanger

A method of enhancing the operational efficiency of a combined refrigeration system having a refrigeration compressor for compressing gaseous refrigerant and a liquid refrigerant pump for receiving and discharging a liquid refrigerant, the method comprising the steps of:

• exposing the liquid refrigerant within a pre-cooling circuit to the gaseous refrigerant prior to the liquid refrigerant entering the liquid pump;
• enclosing the refrigeration compressor and the liquid refrigerant pump within a sealable housing;
• providing the pre-cooling circuit within the housing, the liquid refrigerant flowing through the pre-cooling circuit;
• and
• exposing the pre-cooling circuit to the gaseous refrigerant.

A compressor-pump unit for use in a vapor-compression refrigeration system, the compressor-pump unit comprising:

• a driving device including a rotatable shaft;
• a compressor, coupled with a first portion of the shaft, for compressing gaseous refrigerant within the vapor-compression refrigeration system;
• a liquid pump, coupled with a second portion of the shaft, for receiving liquid refrigerant having a first pressure and for discharging the received liquid refrigerant at a second pressure, the second pressure being higher than the first pressure by a predetermined amount such that the discharged liquid refrigerant is subcooled;
• and
• a pre-cooling circuit connected to the liquid pump, the pre-cooling circuit being exposed to the gaseous refrigerant whereby the gaseous refrigerant absorbs heat from the liquid refrigerant, prior to the liquid refrigerant entering the liquid pump, wherein the pre-cooling circuit is a tube.

A compressor-pump unit for use in a vapor-compression refrigeration system, the compressor-pump unit comprising:

• a driving device including a rotatable shaft;
• a compressor, coupled with a first portion of the shaft, for compressing gaseous refrigerant within the vapor-compression refrigeration system;
• a liquid pump, coupled with a second portion of the shaft, for receiving liquid refrigerant having a first pressure and for discharging the received liquid refrigerant at a second pressure, the second pressure being higher than the first pressure by a predetermined amount such that the discharged liquid refrigerant is subcooled;
• and
• a pre-cooling circuit connected to the liquid pump, the pre-cooling circuit being exposed to the gaseous refrigerant whereby the gaseous refrigerant absorbs heat from the liquid refrigerant, prior to the liquid refrigerant entering the liquid pump, wherein the pre-cooling circuit is an interstitial space defined between the gaseous refrigeration and the liquid pump.