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:
Jun. 04, 2002
Filed:
Jun. 12, 2001
John Louis Griffiths, Pittsburgh, PA (US);
Paul Higginbotham, Guildford, GB;
Air Products and Chemicals, Inc., Allentown, PA (US);
Abstract
A process for the cryogenic distillation of air uses a distillation column system having a supplemental column and a distillation unit including a lower-pressure column and a higher-pressure column. A liquid stream enriched in oxygen is withdrawn from the lower-pressure column and is eventually vaporized through indirect latent heat transfer, thereby producing a reflux stream, a portion of which is eventually sent to the lower-pressure column, the higher-pressure column, and/or the supplemental column. At least a portion of the reflux for the supplemental column is eventually derived from the distillation unit. A nitrogen-enriched liquid removed from the distillation unit is increased in pressure and is fed to the supplemental column or back to the distillation unit. An oxygen-enriched fluid from the bottom of the supplemental column is fed to the distillation unit. At least some of the nitrogen product from the supplemental column is returned to the distillation unit.