Abstract: A PSA process involving the storage of products of various purities in segregated storage tanks for subsequent usage is disclosed. Products of increasing purities, admitted at the product end of the bed, are used during purging and repressurization steps. In addition, different composition streams collected at the feed end of the bed during the countercurrent depressurization step are admitted at the feed end of the bed, in the order of increasing product component content, during the rising pressure step(s). This cycle gives higher recovery and lower bed size factor than prior art PSA cycles.
Type:
Grant
Filed:
December 9, 1997
Date of Patent:
December 28, 1999
Assignee:
Praxair Technology, Inc.
Inventors:
Mohamed Safdar Allie Baksh, Frank Notaro
Abstract: An air separation system and method for producing a plurality of oxygen product streams at varying pressures and purities. The system combines a VPSA oxygen generator with a multi-stage cascade membrane unit to provide a high pressure, low purity product stream and a low pressure, high purity product stream.
Type:
Grant
Filed:
February 14, 1997
Date of Patent:
October 27, 1998
Assignee:
Praxair Technology, Inc.
Inventors:
Ravi Prasad, Pauline Jane Cook, Christian Friedrich Gottzman