The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 19, 1989
Filed:
Nov. 29, 1988
Douglas V Eyre, Walnut Creek, CA (US);
Liquid Air Engineering Corporation, Walnut Creek, CA (US);
Abstract
A process and apparatus for the ultrapurification of cryogenic low boiling liquified gases such as oxygen and nitrogen which contain trace impurities. The impure gas is introduced into a first distillation column and is substantially at its liquid-gas equilibrium temperature at the pressures within the first distillation column. Here the gas is separated by distillation into a first vapor fraction containing low boiling point impurities and a first liquid fraction containing high boiling point impurities. The first vapor fraction is withdrawn and introduced into a second distillation column. The first vapor fraction is substantially at the liquid-gas equilibrium temperature at the pressures within the second distillation column. Here the vapor fraction is separated by distillation into a second vapor fraction containing high boiling point impurities and a second liquid fraction free of trace impurities which is withdrawn as product. Cooling for the process is provided by indirect heat exchange with a cryogenic low boiling gas such as nitrogen, oxygen, or air. The gas to be purified as well as the heat exchange gas can be obtained from a standard air separation unit or the process can be conducted using gases obtained from storage.