Air separation
US5715706A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Aug 29, 1996 |
| Grant date | Feb 10, 1998 |
| Priority date | — |
| Expiry date | Aug 29, 2016 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S62/90
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
Cooled and purified air is introduced into a higher pressure rectification column and separated into oxygen-enriched liquid and nitrogen vapour. A stream of the oxygen-enriched liquid is flashed through a pressure reducing valve to form a mixture of liquid further enriched in oxygen and vapour depleted of oxygen. The liquid is reboiled by reboiler. A stream of the further enriched liquid is reboiled in condenser and is introduced into a lower pressure rectification column for separation into oxygen and nitrogen products. Reflux for the columns and is formed by condensing in condenser nitrogen vapour separated in the higher pressure rectification column. A reboiler provides an upward flow of vapour through the column. The condenser and reboiler take the form of a single heat exchanger. The reboiler is located in a phase separator, the reboiler is located in a rectification column containing liquid-vapour contact devices above the level at which fluid issuing from the valve is introduced. Oxygen-depleted vapour is condensed in the condenser by heat exchange with the further enriched liquid and at least some of the resulting condensate introduced into the lower pressure rectification …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.