Cryogenic rectification method and apparatus
US5471842A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 17, 1994 |
| Grant date | Dec 5, 1995 |
| Priority date | — |
| Expiry date | Aug 17, 2014 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF25J2245/02
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A cryogenic rectification method for producing a product stream from a gaseous mixture having higher and lower volatility components and heavy impurities. In accordance with the method, the mixture is separated by a cryogenic rectification process employing one or more columns having plates, trays or packing for intimately contacting ascending vapor and descending liquid streams within the column. The mixture to be separated after having been compressed is combined with the recycle stream to produce a combined stream which is purified in a prepurification unit that is designed to remove the heavy contaminants. The combined steam is divided into major and minor streams. The major stream is then cooled and separated into liquid and vapor phases. Heavy impurities concentrate in the liquid phase taken as the recycle stream, which is then pumped to a high enough pressure for vaporization of the impurities. The resulting vapor is then reduced in pressure and combined with the incoming gaseous mixture. The concentration of heavy impurities in the vapor phase is reduced to a sufficient extent such that a product stream concentrated in the lower volatility component will have a reduction in…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.