Process to produce a krypton-xenon concentrate from a liquid feed

Claim 1

A process for the production of a krypton-xenon concentrate from a liquid feed, while also recovering a liquid product substantially free of rare gases, comprising enabling avoidance of excessive complication(s) occasioned by the handling of oxygen by the steps of: (A) providing a feed liquid comprising oxygen, krypton and xenon to a reboiling zone to form a reboiling liquid; (B) partially vaporizing the reboiling liquid to produce a vapor, and a liquid krypton-xenon concentrate; (C) recovering krypton-xenon concentrate; (D) passing the vapor against downflowing reflux liquid in a column; (E) stripping krypton and xenon from the vapor to the reflux liquid to produce a lean vapor and a richer liquid; (F) passing the richer liquid to the reboiling zone to form part of the reboiling liquid; (G) withdrawing lean vapor from the column; (H) heating the withdrawn lean vapor; (I) compressing the heated lean vapor; (J) cooling the compressed lean vapor by indirect heat exchange with the heating lean vapor; (K) condensing the cooled lean vapor in the reboiling zone by indirect heat exchange with the partially vaporizing reboiling liquid to produce a lean liquid; (L) passing a portion of the lean liquid to the column to form said reflux liquid; and (M) recovering a portion of lean liquid as liquid product substantially free of rare gases.