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:
Aug. 15, 1995
Filed:
Jan. 18, 1994
Pascal Arriulou, Saint Maurice, FR;
L'Air Liquide, Societe Anonyme Pour L'Etude, Paris, FR;
Abstract
Process and installation for the production of ultrapure nitrogen by distillation of air, wherein the air to be treated is separated in a first column (6) into nitrogen at the head and liquid at the bottom rich in oxygen. The nitrogen in the head is used to circulate in a refrigeration cycle, a flow of high pressure cycle nitrogen being purified from hydrogen in a second column (7) comprising a bottom vaporizer (11) which ensures the condensation of this nitrogen before its introduction into this second column, and a head condenser (10) cooled by the bottom liquid of the first column (6). The ultra-pure production nitrogen is withdrawn (at 24) from the bottom of the second column (7), and a second high pressure cycle nitrogen flow is condensed (in 10; 10A) by vaporization of the bottom liquid of the first column (6). At least a portion of the nitrogen condensed by vaporization of bottom liquid of the first column (6) is purified of hydrogen in the second column (7), and at least a portion of the nitrogen condensed by vaporization of bottom liquid in the first column (6) is introduced as reflux into the head of the first column (6).