System and method for recovery of non-condensable gases such as neon, helium, xenon, and krypton from an air separation unit

Abstract

A system and method for recovery of rare gases such as neon, helium, xenon, and krypton in an air separation unit is provided. The rare gas recovery system comprises a non-condensable stripping columnlinked in a heat transfer relationship with a xenon-krypton column via an auxiliary condenser-reboiler. The non-condensable stripping column produces a rare gas containing overhead that is directed to the auxiliary condenser-reboiler where most of the neon is captured in a non-condensable vent stream that is further processed to produce a crude neon vapor stream that contains greater than about 50% mole fraction of neon with the overall neon recovery exceeding 95%. The xenon-krypton column further receives two streams of liquid oxygen from the lower pressure column and the rare gas containingoverhead from the non-condensable stripping column and produces a crude xenon and krypton liquid stream and an oxygen-rich overhead.

Description

technical field [0001] The present invention relates to systems and methods for recovering noble gases such as neon, helium, xenon and krypton from air separation plants, and more particularly to systems and methods for recovering neon and other noncondensable gases, Including a thermally coupled non-condensable stripping column and a xenon-krypton column arranged in operative association with an auxiliary condenser-reboiler and a second reflux condenser, all fully integrated within the air separation unit. The recovered crude neon vapor stream contains greater than about 50 mole percent neon with an overall neon recovery of greater than about 95%. Additionally, crude xenon and krypton streams are produced in the xenon-krypton column. Background technique [0002] A cryogenic air separation unit (ASU) is typically designed, constructed and operated to meet the baseload product make-up needs / requirements of one or more end-user customers, and optionally to meet local or merc...

AI Technical Summary

Problems solved by technology

In addition, since none of the above-mentioned prior art neon recovery systems have the ability to easily and efficiently co-generate xenon and krypton, further needs include noble gas recovery systems that have a total neon recovery greater than about 95%, and Can co-produce a crude neon vapor stream containing greater than about 50 mole percent neon and greater than about 50 mole percent helium, and can produce xenon and krypton in commercial quantities

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