Patent ID: 11965694
Assignee: L'AIR LIQUIDE, SOCIETE ANONYME POUR L'ETUDE ET L'EXPLOITATION DES PROCEDES GEORGES CLAUDE
Field: Chemical engineering (Chemistry)
Classification: CPC F | IPC F

Claim 9:
10. An apparatus for separation of a mixture comprising carbon monoxide, hydrogen and methane, the apparatus comprising:
a scrubbing column having a top portion and/or at least one phase separator;
a stripping column having a top portion and a bottom portion;
a separation column having a top portion and a bottom portion;
a heat exchanger;
means for sending the mixture to be cooled to a cryogenic temperature to the heat exchanger;
means for sending the cooled mixture or a fluid derived from said cooled mixture to the scrubbing column fed at the top portion with a liquid containing at least 80 mol % carbon monoxide and/or to at least one phase separator;
means for withdrawing a bottom liquid from the scrubbing column and/or the at least one phase separator, wherein the bottom liquid is depleted in hydrogen with respect to the mixture;
means for sending the withdrawn bottom liquid to the stripping column;
means for withdrawing a gas at the top portion of the stripping column;
means for sending a bottom liquid from the stripping column to the separation column, wherein the separation column is configured to separate the bottom liquid into a top gas enriched in carbon monoxide and a liquid enriched in methane;
means for withdrawing the liquid enriched in methane from the bottom of the separation column, wherein the means for withdrawing the liquid enriched in methane are in fluid communication with the heat exchanger in order to form gaseous methane;
a compressor;
means for sending the gaseous methane to the compressor; and
means for returning a part of the gaseous methane following compression in the compressor to the bottom portion of the separation column for separation therein,
wherein the separation column comprises a top condenser that is cooled by a closed refrigeration cycle, wherein the closed refrigeration cycle is selected from the group consisting of a closed nitrogen refrigeration cycle and a closed carbon monoxide refrigeration cycle,
wherein the part of the gaseous methane following compression that is returned to the bottom of the separation column has the same methane concentration as the liquid enriched in methane withdrawn the bottom portion of the separation column.