SEPARATION OF CARBON DIOXIDE AND HYDROGEN

摘要

A process is described for removing carbon dioxide from a synthesis gas feed stream in a cryogenic separation plant. In an example described the synthesis gas feed stream (3) comprises 40 to 65 mole % hydrogen and is fed to a single stage or a first stage of a series of separation stages (120, 103, 104) at a pressure in the range of 46 to 90 bar absolute. The single stage or a stage of the series is operated at a temperature in the range of−53 to−48° C. and a pressure in the range of 44 to 90 bar absolute. In some examples, the single stage or the combined stages of the series remove 70 to 80% of the total moles of carbon dioxide in the synthesis gas feed stream. Liquefied C02 product stream(s) discharged from the stage (s) (7,10,13) of the cryogenic separation plant may be sequestrated and/or used in a chemical process (71).