Abstract 1,054,149. Liquefaction and re-vaporization of natural gas. SHELL INTERNATIONALE RESEARCH MAATSCHAPPIJ N.V. Nov. 8, 1965 [Nov. 9, 1964], No. 47244/65. Heading F4P. Liquefaction of natural hydrocarbon gas or revaporization of the gas in the liquid phase is effected by heat exchange with a refrigerant having a freezing point at atmospheric pressure near the boiling point of methane and having a boiling point above or slightly below ambient temperature. Suitable refrigerants include isobutane, isopentane, isohexane and mixtures thereof. After revaporization of liquid methane transported by tanker, the so-cooled refrigerant is fed into the tanker reservoir, transported back to the supply port and used to liquefy natural gas being loaded into the tanker. The so warmed refrigerant may be used as fuel or transported back to the unloading port.
A METHOD OF TRANSPORTING A GAS COMPRISING THE FOLLOWING STAGES: (A) A FIRST QUANTITY OF GAS IS LIQUEFIED AT A PRODUCTION POINT BY COOLING AND IS PASSED IN THE LIQUID STATE INTO A RESERVOIR IN WHICH A PRESSURE OF AT LEAST APPROXIMATELY ONE ATMOSPHERE IS MAINTAINED; (B) THE RESERVOIR CONTAINING THE LIQUID GAS IS TRANPORTED TO A CONSUMPTION POINT; (C) AT THE CONSUMPTION POINT THE LIQUID GAS IS CONVERTED TO THE GASEOUS STATE BY BRINGING IT INTO HEAT EXCHANGE WTH A LIQUID REFRIGERANT HAVING AN ATMOSPHERIC PRESSURE BOILING TEMPERATURE ABOVE OR SLIGHTLY BELOW THE AMBIENT TEMPEATURE AND AN ATMOSPHERIC PRESSURE FREEZING TEMPERATURE BELOW OR SLIGHTLY ABOVE THE ATMOSPHERIC PRESSURE BOILING TEMPERATURE OF SAID GAS TO FURTHER COOL SAID REFRIGERANT WITHIN THE LIQUID PHASE RANGE; (D) THE COOLED LIQUID REFRIGERANT IS PASSED INTO AN INSULATED RESERVOIR IN WHICH A PRESSURE OF APPROXIMATELY ONE ATMOSPHERE IS MAINTAINED; (E) THE INSULATED RESERVOIR FILLED WITH SAID COOLED LIQUID REFRIGERANT IS TRANSFERRED TO THE GAS PRODUCTION POINT, SAID REFRIGERANT BEING PRESERVED IN THE LIQUID PHASE AT APPROXIMATELY ONE ATMOSPHERE PRESSURE BY THE INSULATION OF SAID RESERVOIR; (F) AT SAID GAS PRODUCTION POINT A SECOND QUANTITY OF GASEOUS GAS IS COOLED ACCORDING TO STAGE (A), AT LEAST SOME OF THE HEAT OF VAPORIZATION OF SAID GAS BEING TRANSFERRED IN HEAT EXCHANGE WITH SAID LIQUID REFRIGERANT.
Claim 2
Independent Claim
219 words
A METHOD OF TRANSPORTING A GAS COMPRISING THE FOLLOWING STAGES: (A) A FIRST QUANTITY OF GAS IS LIQUEFIED AT A PRODUCTION POINT BY COOLING AND IS PASSED IN THE LIQUID STATE INTO A RESERVOIR IN WHICH A PRESSURE OF AT LEAST APPROXIMATELY ONE ATMOSPHERE IS MAINTAINED; (B) THE RESERVOIR CONTAINING THE LIQUID GAS IS TRANPORTED TO A CONSUMPTION POINT; (C) AT THE CONSUMPTION POINT THE LIQUID GAS IS CONVERTED TO THE GASEOUS STATE BY BRINGING IT INTO HEAT EXCHANGE WTH A LIQUID REFRIGERANT HAVING AN ATMOSPHERIC PRESSURE BOILING TEMPERATURE ABOVE OR SLIGHTLY BELOW THE AMBIENT TEMPEATURE AND AN ATMOSPHERIC PRESSURE FREEZING TEMPERATURE BELOW OR SLIGHTLY ABOVE THE ATMOSPHERIC PRESSURE BOILING TEMPERATURE OF SAID GAS TO FURTHER COOL SAID REFRIGERANT WITHIN THE LIQUID PHASE RANGE; (D) THE COOLED LIQUID REFRIGERANT IS PASSED INTO AN INSULATED RESERVOIR IN WHICH A PRESSURE OF APPROXIMATELY ONE ATMOSPHERE IS MAINTAINED; (E) THE INSULATED RESERVOIR FILLED WITH SAID COOLED LIQUID REFRIGERANT IS TRANSFERRED TO THE GAS PRODUCTION POINT, SAID REFRIGERANT BEING PRESERVED IN THE LIQUID PHASE AT APPROXIMATELY ONE ATMOSPHERE PRESSURE BY THE INSULATION OF SAID RESERVOIR; (F) AT SAID GAS PRODUCTION POINT A SECOND QUANTITY OF GASEOUS GAS IS COOLED ACCORDING TO STAGE (A), AT LEAST SOME OF THE HEAT OF VAPORIZATION OF SAID GAS BEING TRANSFERRED IN HEAT EXCHANGE WITH SAID LIQUID REFRIGERANT.