Method and apparatus for low-temperature separation of gases

Claim 1

A PROCESS FOR LOW TEMPERATURE SEPARATION OF GAS MIXTURES AND COMPRISING THE STEPS OF RECTIFYING A FIRST PART OF THE GAS MIXTURE TO BE SEPARATED IN A FIRST COLUMN TO OBTAIN A LOWER BOILING POINT PRODUCT AND A LIQUID ENRICHED WITH A HIGHER BOILING POINT COMPONENT OF SAID GAS MIXTURE; EXPANDING A SECOND PART OF THE GAS MIXTURE TO BE SEPARATED TO PRODUCE EXTERNAL WORK; RECTIFYING SAID SECOND PART OF THE GAS MIXTURE TO BE SEPARATED IN A THIRD COLUMN TO OBTAIN A LOWER BOILING POINT PRODUCT AND A LIQUID ENRICHED WITH A HIGHER BOILING POINT COMPONENET OF SAID GAS MIXTURE, WITHDRAWING THE LIQUIDS ENRICHED WITH A HIGHER BOILING COMPONENT OF SAID GAS MIXTURE FROM SAID FIRST COLUMN AND SAID THIRD COLUMN AND RECTIFYING THESE IN A SECOND COLUMN SO THAT RECTIFICATION VAPORS PASS UPWARDLY THROUGH PERFORATED BAFFLES, AND LIQUIDS ACCUMULATE ON THE PERFORATED BAFFLES TO OBTAIN A LOWER BOILING POINT PRODUCT AND A HIGHER BOILING POINT PRODUCT, THE FIRST COLUMN BEING AT A HIGHER PRESSURE THAN THE SECOND COLUMN; STORING THE LOWER BOILING POINT PRODUCT PRODUCED IN THE FIRST COLUMN; AND INTERMITTENTLY RELEASING THE STORED LOWER BOILING POINT PRODUCT INTO