System for separation of argon from air

Claim 1

A PROCESS OF SEPARATING ARGON FROM AIR, WHICH PROCESS COMPRISES REFRIGERATING AIR AT ELEVATED PRESSURES IN COLD ACCUMULATORS COOLED TO RELATIVELY LOW TAEMPERATURE, RECTIFYING THE REFRIGERATED AIR INTO ITS MAJOR CONSTITUENTS INCLUDING AN OXYGEN FRACTION CONTAINING ARGON AND A NITROGEN FRACTION, SEPARATELY WITHDRAWING SAID FRACTIONS AND COOLING SAID ACCUMULATORS THEREWITH WHILE DIVERTING A PORTION OF SAID OXYGEN FRACTION PASSING TO SAID ACCUMULATORS, LIQUEFYING SAID DIVERTED PORTION OF SAID OXYGEN FRACTION AND RECTIFYING SAID LIQUEFIED PORTION TO A LIQUID OXYGEN RESIDUE AND AN OVERHEAD FRACTION CONTAINING ARGON WHILE SUBJECTING THE SEPARATED ARGON IN A RECTIFYING ZONE TO THE REFLUX PRODUCED BY CONTINUOUS INDIRECT HEAT EXCHANGE BETWEEN THE SAID SEPARATED ARGON AND SAID LIQUID OXYGEN RESIDUE AND WHILE CORRECTING FOR IMBALANCE IN THE ACCUMULATORS BY STEPS COMPRISING THE FOLLOWING: COMPRESSING AN AMOUNT OF AIR EQUIVALENT TO THE AMOUNT OF THE SAID DIVERTED PORTION OF SAID OXYGEN FRACTION, COOLING THE SAID LATTER AIR IN HEAT EXCHANGE RELATAIONSHIP WITH COLD SEPARATED NITROGEN IN THE FIRST-MENTIONED RECTIFYING STEP, PASSING SAID LATTER COOLED AIR INTO HEAT EXCHANGE RELATIONSHIP WITH THE SAID LIQUID OXYGEN RESIDUE OBTAINED IN THE SECOND-MENTIONED RECTIFYING STEP AND SUPPLYING THE SO TREATED LATTER AIR TO THE FIRST-MENTIONED RECTIFYING STEP FOR FRACTIONATION WITH THE FIRST-MENTIONED AIR.