摘要 |
Process for the purification and separation of a synthesis gas stream containing hydrogen, carbon monoxide and carbon dioxide in which synthesis gas is purified in a purification unit (W) involving a methanol washing step to remove carbon dioxide, the carbon dioxide depleted synthesis gas is purified by adsorption (P) to produce a purified synthesis gas stream and the purified gas stream is sent to a cryogenic separation unit (C) where it is cooled and separated by cryogenic separation in a column of a column system, at least one stream (13) enriched in carbon monoxide is removed from a column of the column system, warmed and divided in two, one part of the stream being removed from the cryogenic separation unit as a first stream, the other part of the stream forming a second stream (13B, 15B) and being sent to the purification unit wherein it is warmed and the warmed second stream is mixed with the first stream. |