Patent ID: 7216505
Filing Date: 2007-05-15
Classification: F25B

Abstract:
1. A multiple stage recirculated single feed refrigeration system, the system comprising: a first high stage compressor for compressing vapor refrigerant from a first evaporator via a first recirculator; a condenser for receiving hot vapor refrigerant from the first compressor and condensing the hot vapor refrigerant to a liquid refrigerant; a high pressure receiver for feeding high pressure liquid refrigerant to the first recirculator; a second compressor for compressing vapor refrigerant from a second evaporator via a second recirculator and wherein the second recirculator is fed by liquid refrigerant from the first recirculator and the second evaporator is fed by the second recirculator; a third compressor for compressing vapor refrigerant from a third evaporator via a separator vessel wherein the third evaporator is fed by the second recirculator wherein excess liquid refrigerant is transferred to the separator vessel; a liquid transfer vessel for receiving excess liquid refrigerant from the separator vessel; a motorized valve in connection between the separator vessel and the liquid transfer vessel for controlling flow of the liquid refrigerant to the liquid transfer vessel; and a refrigerant liquid pump for transferring excess liquid refrigerant from the liquid transfer vessel to the second recirculator and for transferring liquid refrigerant to the high pressure receiver.