PROCESS AND DEVICE FOR THE CRYOGENIC SEPARATION OF A METHANE-RICH STREAM

摘要

In a process for the cryogenic separation of a methane-rich feed stream (4) containing oxygen and nitrogen, the feed stream is cooled in order to produce a cooled stream, at least one portion of the cooled stream is sent to a distillation column (6), a bottom stream is withdrawn from the distillation column, the bottom stream being enriched in methane compared to the feed stream, a stream enriched in oxygen compared to the feed stream is withdrawn from the distillation column and a recycle stream (9) is introduced to the top of the column in liquid form in order to be separated, this stream being constituted by a liquid originating from the column which is enriched in methane compared to the feed stream.