Patent · US Expired

Plural stage distillation of a natural gas stream

US3983711A · kind A · utility

42Cited by
2References
14Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJan 2, 1975
Grant dateOct 5, 1976
Priority date
Expiry dateJan 2, 1995

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02P20/151
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

Natural gas, containing carbon dioxide and nitrogen, is demethanized in a first fractional distillation tower to provide an overhead of nitrogen and methane free of carbon dioxide and components heavier than methane. A sidestream is withdrawn from the first tower at a point therein where carbon dioxide concentration is maximized and the sidestream is fractionated in a second tower to recover methane and carbon dioxide as overhead. Nitrogen is rejected from the carbon dioxide free overhead from the first tower by liquefaction of methane to provide a send-out gas free of nitrogen. The cold potential of various streams is used to provide cooling requirements for the process.

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