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:
Apr. 17, 1990
Filed:
Mar. 08, 1989
John T Lavin, Guildford, GB;
David J Layland, Basingstoke, GB;
The BOC Group, Inc., Murray Hill, NJ (US);
Abstract
A process for the separation of air to obtain oxygen, nitrogen and argon is disclosed which comprises: subjecting air from which carbon dioxide and water have been removed to fractional distillation in a first column to form oxygen-nitrogen vapor and argon-enriched oxygen; separating argon from the latter in a second column operating at substantially lower pressure than the first; liquefying a portion of the nitrogen vapor in a cycle including heat exchange with incoming air and compression to a pressure above that of the first column, a portion of the liquid nitrogen being taken as product and a second portion being returned to the first column as reflux. Liquid-oxygen and nitrogen vapor from the first column are mixed in a liquid-vapor contact column, impure liquid nitrogen is withdrawn therefrom and used as reflux in the first column. A remixed oxygen-nitrogen stream is withdrawn from the contact column and expanded to create refrigeration for the system. Also, disclosed is apparatus for carrying out the subject process.