Patent · US Expired

Nitrogen generator with waste distillation and recycle of waste distillation overhead

US4848996A · kind A · utility

15Cited by
13References
3Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 6, 1988
Grant dateJul 18, 1989
Priority date
Expiry dateOct 6, 2008

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF25J2245/02
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

The present invention is an improvement to a standard nitrogen generator. The improvement is two-fold; first, the addition of one or more distillation stages above the reboiler, which stages effectively transform the reboiler/condenser into a partial low pressure column and allow further separation (rectification) of the nitrogen generator bottoms liquid into two streams. Second, the recycle of the overhead stream (at a composition close to that of air) from the top of the low pressure column to the main air compressor. Additionally, at least a portion of the oxygen-enriched stream that exits the low pressure column below the bottom tray is expanded to provide refrigeration for the cycle.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.