PROCESS AND APPARATUS FOR THE SEPARATION BY CRYOGENIC DISTILLATION OF A MIXTURE OF METHANE, CARBON DIOXIDE AND HYDROGEN

摘要

In a process for the cryogenic separation of a feed mixture of at least carbon monoxide, hydrogen and methane, the feed mixture is separated in a methane wash column (1) fed by a liquid methane stream (11) at the top of the methane wash column to produce a gas (12) enriched in hydrogen, a liquid stream (13) from the bottom of the methane wash column is treated to produce a mixture of carbon monoxide and methane (15), the mixture of carbon monoxide and methane is separated in a separation column (3) to produce a gas enriched in carbon monoxide (16) and a liquid methane flow (4) at least part of which forms a purge stream (20), the purge stream being varied to take account of load variations.