Patent · US Expired

Air separation

US5237822A · kind A · utility

12Cited by
3References
8Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJan 10, 1992
Grant dateAug 24, 1993
Priority date
Expiry dateJan 10, 2012

Classification

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

Abstract

Air is compressed in a compressor and has water vapor and carbon dioxide removed therefrom in an apparatus. A portion of the resulting purified air is then cooled by passage through a main heat exchanger to a temperature suitable for its separation by rectification. The air is then introduced into the higher pressure stage of a double rectification column (which also has a lower pressure stage). Liquid oxygen is withdrawn from the lower pressure stage by a pump and is vaporized by passage through the heat exchanger countercurrently to the aforementioned air to form a high pressure gaseous oxygen product. A second portion of the purified air is further compressed in compressors and is then passed through the heat exchanger 6 countercurrently to the oxygen product, thereby helping to warm such product. A part of the first portion of air is withdrawn from an intermediate region of the heat exchanger, is expanded in a turbine and is introduced into the lower pressure rectification stage. A part of the second portion of the air is taken from intermediate the compressors and is passed through the heat exchanger, being withdrawn therefrom at an intermediate location thereof. This air stre…

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