Air separation
US5689975A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 9, 1996 |
| Grant date | Nov 25, 1997 |
| Priority date | — |
| Expiry date | Oct 9, 2016 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S62/924
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A stream of precooled and purified air is introduced into a double rectification column comprising a higher pressure rectification column and a lower pressure rectification column and is separated therein into an oxygen-rich fraction and a nitrogen-rich fraction. A stream of argon-enriched oxygen vapor flows from an outlet of the lower pressure rectification column into a side column in which argon is separated therefrom. An oxygen-enriched liquid air stream is taken from an outlet at the bottom of the higher pressure rectification column. A vaporous oxygen-enriched air stream is introduced into the lower pressure rectification column through an inlet above the outlet. At least part of the oxygen-enriched liquid is separated in a further or intermediate pressure rectification column provided with a reboiler, thereby forming a vapor depleted of oxygen and a liquid air stream further enriched in oxygen. At least one stream of the further-enriched liquid is vaporised to form the oxygen-enriched vapor that is introduced into the lower pressure rectification column. A part of the oxygen-depleted vapor is condensed in a condenser and is taken as product or reintroduced into the lower pre…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.