Patent ID: 7357003
Filing Date: 2008-04-15
Classification: B01D,C10G,C10L,F25J

Abstract:
1. A process for separation of hydrocarbons to separate a feed gas comprising at least methane and a hydrocarbon less volatile than methane, in a distillation column, into a residue gas enriched with methane and lean in the hydrocarbon less volatile than methane and a heavier fraction lean in methane and enriched with the hydrocarbon less volatile than methane, comprising the steps of: (a) said feed gas is cooled and partly condensed, and separated into a gas and a liquid; (b) the liquid obtained in step (a) is supplied to a distillation column; (c) the gas obtained in step (a) is expanded by an expander and partly condensed, and separated into a gas and a liquid; (d) the liquid obtained in step (c) is supplied to the distillation column; (e) the gas obtained in step (c) is divided into a first gas portion and a second gas portion; (f) said first gas portion is supplied to the distillation column; (g) said second gas portion is condensed by being compressed and cooled, and then depressurized and supplied as a reflux to the distillation column; and (h) said residue gas enriched with methane and lean in the hydrocarbon less volatile than methane is obtained from the top part of the distillation column and said heavier fraction lean in methane and enriched with the hydrocarbon less volatile than methane is obtained from the bottom part of the distillation column.