Refrigeration system with a compressor-pump unit and a liquid-injection desuperheating line

A vapor-compression refrigeration system for providing cooling with improved efficiency through utilization of liquid pressure amplification and liquid injection desuperheating, the refrigeration system comprising:

• a condenser, an expansion device, an evaporator and a compressor each being interconnected with refrigerant piping, wherein refrigerant sequentially flows through the condenser, the expansion device, the evaporator, and the compressor;
• a liquid pump interposed between, and interconnected with, the condenser and the expansion device, the liquid pump including an inlet port for receiving liquid refrigerant from the condenser having a first pressure and a discharge port through which the received liquid refrigerant is discharged 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;
• a sealable housing within which the first and second portions of the shaft, the compressor, and the liquid pump are supported;
• a driving device including a rotatable shaft, wherein the compressor is coupled with a first portion of the shaft and the liquid pump is coupled with a second portion of the shaft;
• and
• a liquid injection assembly including a liquid injection pipe section, the liquid injection pipe section having an inlet downstream of a discharge port of the liquid pump and an outlet in a discharge pathway of the compressor, whereby a volume of the liquid refrigerant discharged by the liquid pump is diverted into gaseous refrigerant being discharged from the compressor to desuperheat the gaseous refrigerant within the compressor discharge pathway.

A method of enhancing the operational efficiency of a vapor-compression refrigeration system having a compressor driven by a rotatable shaft of a driving device, a condenser, an expansion valve, and an evaporator serially connected by refrigerant piping, the method comprising the steps of:

• interposing a liquid pump between the condenser and the expansion valve, wherein the liquid pump is connected to the condenser and the expansion valve with the refrigerant piping;
• coupling the liquid pump to the rotatable shaft of the driving device, whereby the compressor and the liquid pump may be concurrently driven by the driving device;
• positioning and supporting the compressor and the liquid pump within a sealable housing through which the rotatable shaft sealably passes, wherein the housing includes a pump cooling refrigerant pathway for directing gaseous refrigerant from the evaporator into heat transfer contact with a pump casing of the liquid pump;
• driving the compressor with the rotatable shaft of the driving device to pump gaseous refrigerant received by the compressor from the evaporator through the condenser;
• and
• concurrently with the compressor driving step, driving the liquid pump with the rotatable shaft of the driving device to pump liquid refrigerant received from the condenser at a first liquid refrigerant pressure to the expansion valve at a second liquid refrigerant pressure, the second liquid refrigerant pressure being higher than the first liquid refrigerant pressure by a predetermined amount, whereby the liquid refrigerant is subcooled.