Refrigeration of liquefied gases

Claim 1

A PROCESS FOR THE REFRIGERATION OF A LIQUID COMPRIING A LIQUEFIED FIRST NORMALLY GASEOUS MATERIAL CONTAINING A SECOND NORMALLY GASEOUS MATERIAL HAVING A NORMAL BOILING POINT BELOW THE NORMAL BOILING POINT OF THE FIRST MATERIAL COMPRISING WITHDRAWING A STREAM OF SAID LIQUID FROM A ZONE CONTAINING SAID LIQUID, REDUCING THE PRESSURE OF THE WITHDRAWN LIQUID WHEREVY AT LEAST A PORTION OF THE REDUCE PRESSURE LIQUID VAPORIZES, PASSING THE SO PRODUCED VAPOR AND ANY UNVAPORIZED LIQUID INTO INDIRECT HEAT EXCHANGE WITH LIQUID REMAINING IN SAID ZONE WHEREIN SAID UNVAPORIZED LIQUID VAPORIZES, WITHDRAWING VAPORS FROM THE HEAT EXCHANGE STEP, COMPRESSING THE WITHDRAWN VAPORS, CONDENSING THE COMPRESSED VAPORS THEREBY PRODUCING CONDENSATE, WITHDRAWING FURTHER LIQUID FROM SAID ZONE REDUCING PRESSURE ON THIS FURTHER WITHDRAWING LIQUID AND PASSING SAME IN INDIRECT HEAT EXCHANGE WITH SAID CONDENSATE WHEREBY SAID CONDENSATE IS CHILLED AND THE PRESSURE REDUCED FURTHER WITHDRAWN LIQUID IS VAPORIZED, INTRODUCING THESE LATTER FORMED VAPORS INTO SAID COMPRESSING STEP AND INTRODUCING THE CHILLED CONDENSATE INTO SAID ZONE.