Abstract In a system for the liquefaction of natural gas by a closed refrigeration cycle operated with a refrigerant mixture, wherein the refrigerant mixture is conducted through a hermetically sealed cycle comprising a cycle compressor, a low-pressure cycle section and a high-pressure cycle section, and wherein when the cycle compressor is cut off, the pressure in the low-pressure cycle section would build up to a pressure above the maximum design pressure of said low-pressure section in the absence of a pressure relief valve, THE IMPROVEMENT COMPRISING PROVIDING SUFFICIENT BUFFER VOLUME IN SAID LOW-PRESSURE SECTION TO COMPENSATE FOR SAID BUILD-UP IN PRESSURE, SO SAID REFRIGERANT MIXTURE DOES NOT ESCAPE THROUGH SAID PRESSURE RELIEF VALVE.
IN A PROCESS FOR THE LIQUEFACTION OF NATURAL GAS BY A CLOSED "ONE FLOW CASCADE" REFRIGERATION CYCLE OPERATED WITH A REFRIGERNT MIXTURE, WHEREIN THE REFRIGERANT MIXTURE IS CONDUCTED THROUGH A HERMICALLY SEALED CYCLE COMPRISING A CYCLE COMPRESSOR, A LOW-PRESSURE CYCLE SECTION AND A HIGH-PRESSURE CYCLE SECTION, AND WHEREIN WHEN THE CYCLE CMPRESSOR IS CUT OFF, THE PRESSURE IN THE LOW-PRESSURE CYCLE SECTION WOULD BUILD UP TO A PRESSURE ABOVE THE MAXIMUM DESIGN PRESSURE OF SAID LOWPRESSURE SECTION IN THE ABSENCE OF A PRESSURE RELIEF VALVE THE IMPROVEMENT COMPRISING INTRODUCING SUFFICIENT BUFFER VOLUME IN SAID LOW PRESSURE SECTION WHEN THE CYCLE COMPRESSOR IS CUT OFF, TO COMPENSATE FOR SAID BUILD-UP IN PRESSURE, SO SAID REFRIGERANT MIXTURE DOES NOT ESCAPE FROM SAID CYCLE AND SO THAT PRESSURE RELIEF VALVES VENTING TO THE ATMOSPHERE ARE NOT REQUIRED, SAID BUFFER VOLUME BEING BYPASSING DURING NORMAL OPERATION OF THE CYCLE COMPRESSOR.
Claim 2
Dependent Claim
146 words
IN A PROCESS FOR THE LIQUEFACTION OF NATURAL GAS BY A CLOSED "ONE FLOW CASCADE" REFRIGERATION CYCLE OPERATED WITH A REFRIGERNT MIXTURE, WHEREIN THE REFRIGERANT MIXTURE IS CONDUCTED THROUGH A HERMICALLY SEALED CYCLE COMPRISING A CYCLE COMPRESSOR, A LOW-PRESSURE CYCLE SECTION AND A HIGH-PRESSURE CYCLE SECTION, AND WHEREIN WHEN THE CYCLE CMPRESSOR IS CUT OFF, THE PRESSURE IN THE LOW-PRESSURE CYCLE SECTION WOULD BUILD UP TO A PRESSURE ABOVE THE MAXIMUM DESIGN PRESSURE OF SAID LOWPRESSURE SECTION IN THE ABSENCE OF A PRESSURE RELIEF VALVE THE IMPROVEMENT COMPRISING INTRODUCING SUFFICIENT BUFFER VOLUME IN SAID LOW PRESSURE SECTION WHEN THE CYCLE COMPRESSOR IS CUT OFF, TO COMPENSATE FOR SAID BUILD-UP IN PRESSURE, SO SAID REFRIGERANT MIXTURE DOES NOT ESCAPE FROM SAID CYCLE AND SO THAT PRESSURE RELIEF VALVES VENTING TO THE ATMOSPHERE ARE NOT REQUIRED, SAID BUFFER VOLUME BEING BYPASSING DURING NORMAL OPERATION OF THE CYCLE COMPRESSOR.
Claim 3
Dependent Claim
32 words
A process defined by claim 1, wherein said low-pressure cycle section comprises shell spaces of tubular heat exchangers and conduits to expansion valves and to the intake side of the cycle compressor.