Air separation
CA 2040796 C · Owner: The Boc Group Plc · Inventors: Buttle, Andrea
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A compressed air stream is separated in a double rectification column 8 having a higher pressure stage 10 and a lower pressure stage 12. The lower pressure stage 12 contains a low pressure drop liquid-vapour contact means 13 having a pressure drop of less than 400 Pa per theoretical stage, for example a structured packing to effect mass, transfer between ascending vapour and descending liquid. A product gaseous oxygen stream is withdrawn from the stage 12 through an outlet 36 and is warmed to about ambient temperature in the heat exchanger 6 in countercurrent flow relationship with the compressed air stream which is thereby cooled. Refrigeration for the process is created by expansion of …
Read the whole patent
Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed April 18, 1991 and granted December 25, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 18, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 18, 2013.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.