Patent · US Expired

Method for separating a multi-component feed stream using distillation and controlled freezing zone

US5120338A · kind A · utility

86Cited by
6References
24Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 14, 1991
Grant dateJun 9, 1992
Priority date
Expiry dateMar 14, 2011

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S62/93
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

The invention relates to a method for separating two primary components of a multi-component feed stream (e.g., methane and nitrogen) in the presence of a third, freezable component (e.g., carbon dioxide) having a relative volatility less than that of either primary component. The inventive process employs both a distillation section and a controlled freezing zone ("CFZ"). The freezable component is allowed to freeze in the CFZ, and the resulting solids are collected at the bottom of the CFZ. The CFZ also produces a vapor overhead product enriched in one of the primary components and a liquid bottom product enriched in the other primary component. The solids of the freezable component are melted and mixed with the CFZ liquid bottom product to form a liquid feed stream for the distillation section which operates like a conventional distillation section, while tolerating significantly high concentrations (i.e., >0.1 mole %) of the freezable component without solids formation, at temperatures well below the freezable component's freezing point.

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