Method for separating gaseous mixtures

Claim 1

METHOD OF SEPARATING GASEOUS MIXTURES INTO COMPONENT GASES EMPLOYING A LOW TEMPERATURE FRACTIONATING OPERATION INCLUDING PRELIMINARY SEPARATION IN A FIRST FRACTIONATING ZONE UNDER SUPERATMOSPHERIC PRESSURE PRODUCING GASEOUS LOW BOILING POINT FRACTIN AND LIQUID HIGH BOILING POINT FRACTION AND A FURTHER SEPARATION IN A SECOND FRACTIONATING ZONE UNDER RELATIVELY LOW PRESSURE PRODUCING GASEOUS LOW BOILING POINT COMPONENT AND LIQUID HIGH BOILING POINT COMPONENT, COMPRISING THE STEPS OF PROVIDING COOL GASEOUS MATERIAL UNDER SUPERATOMOSPHERIC PRESSURE FROM COMPRESSED GASEOUS MIXTURE TO BE SEPARATED, THE GASEOUS MIXTURE INCLUDING COMPONENTS OF THE GASEOUS MIXTURE WITH THE PERCENTAGE OF HIGH BOILING POINT COMPONENT BEING LESS THAN THE JPERCENTAGE OF HIGH BOILING POINT COMPONENT OF THE LIQUID HIGH BOILING POINT FRACTION AND GREATER THAN THE PERCENTAGE OF HIGH BOILING POINT COMPONENT OF THE GASEOUS LOW BOILING POINT FRACTION, PERFORMING A FIRST CONDENSING-EVAPORATING STEP INCLUDING ESTABLISHING HEAT INTERCHANGE BETWEEN COOL GASEOUS MATERIAL UNDER SUPERATMOSPHERIC PRESSURE AND LIQUID HIGH BOILING POINT COMPONENT UNDER A PRESSURE CORRESPONDING TO THE PRESSURE OF THE SECOND FRACTIONATING ZONE AND ESTABLISHING HEAT INTERCHANGE BETWEEN COOL GASEOUS MATERIAL UNDER SUPERATMOSPHERIC PRESSURE AND LIQUID HIGH BOILING POINT COMPONENT UNDER A PRESSURE LOWER THAN THE PRESSURE OF THE SECOND FRACTIONATING ZONE TO FURTHER COOL THE GASEOUS MATERIAL AND PROVIDE VAPORIZED LIQUID HIGH BOILING POINT COMPONENT UNDER A PRESSURE CORRESPONDING TO THE PRESSURE OF THE SECOND FRACTIONATING ZONE AND VAPORIZED LIQUID HIGH BOILING POINT COMPONENT UNDER A PRESSURE LOWER THAN THE PRESSURE OF THE SECOND FRACTIONATING ZONE, THE FIRST CONDENSING-EVAPORATING STEP INCLUDING UTILIZATION OF VAPORIZED LIQUID HIGH BOILING POINT COMPONENT UNDER A PRESSURE CORRESPONDING TO THE PRESSURE OF THE SECOND FRACTINATING ZONE AS REBOIL FOR THE SECOND FRACTIONATING ZONE, WITHDRAWING AS PRODUCT VAPORIZED LIQUID HIGH BOILING POINT COMPONENT UNDER A PRESSURE LOWER THAN THE PRESSURE OF THE SECOND FRACTIONATING ZONE, FEEDING FURTHER COOLED GASEOUS MATERIAL TO THE FRACTIONATING OPERATION, LIQUEFYING GASEOUS LOW BOILING POINT FRACTION, AND UTILIZING LIQUEFIED LOW BOILING POINT FRACTION AS REFLUX FOR THE FIRST AND SECOND FRACTIONATING ZONES.