Patent Number: 6,305,191

Title: Separation of air

Abstract: A first stream of air is compressed in a main air compressor and a booster compressor is cooled at a first pressure by passage through a main heat exchanger. The cooled stream is introduced without further compression into the higher pressure column of a double rectification column including in addition to the column a lower pressure column and a condenser-reboiler. A second stream of compressed air is expanded from a second pressure in an expansion turbine with the performance of external work. The expanded second stream of air is introduced into the lower pressure column. An oxygen product, typically impure, is taken from the bottom region of the lower pressure column. The second pressure is less than the first pressure column. The second pressure is less than the first pressure, the second air stream being taken from intermediate the compressors.

Inventors: Higginbotham; Paul (Guildford, GB)

Assignee: The BOC Group plc

International Classification: F25J 3/04 (20060101); F25J 003/04 ()

Expiration Date: 10/23/2018