Patent · US Expired

Air separation

US5331818A · kind A · utility

12Cited by
4References
23Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJun 23, 1993
Grant dateJul 26, 1994
Priority date
Expiry dateJun 23, 2013

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S62/94
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

Air is rectified in a rectification system comprising a higher pressure rectification column, an intermediate pressure rectification column, and a lower pressure rectification column. A first reboiler-condenser provides liquid nitrogen reflux for the higher pressure rectification column and for the lower pressure rectification column and also reboils the intermediate pressure rectification column. Another reboiler-condenser provides liquid nitrogen reflux for the intermediate pressure rectification column and reboils the lower pressure rectification column. Air is fed to the higher pressure rectification column through a pair of inlets. A first oxygen product is withdrawn from the intermediate pressure rectification column by a pump. Gaseous nitrogen products are withdrawn from the intermediate and lower pressure rectification columns through a pair of outlets thereof.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.