Tonnage nitrogen generator
US4222756A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 7, 1979 |
| Grant date | Sep 16, 1980 |
| Priority date | — |
| Expiry date | May 7, 1999 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF25J2250/50
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A process for producing nitrogen which comprises removing all or substantially all carbon dioxide and water vapor from air, introducing said air at between 85 and 125 psia and below -260.degree. F. into a first distillation column, expanding at least part of the overhead product from said first distillation column in an expander to a pressure in the range 45 to 70 psia, expanding at least part of the bottoms product from said first distillation column to a pressure in the range 45 to 70 psia, introducing at least a part of both expanded products into a second distillation column, using at least part of the refrigeration contained in the bottoms product of said second distillation column to provide reflux in said first distillation column, expanding at least a part of the bottoms product from said second distillation column to a pressure equal to or less than 30 psia and using at least part of the refrigeration therein to provide reflux in said second distillation column, and collecting nitrogen product from the top of said second distillation column. The present invention also relates to an apparatus for carrying out the process.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.