Cryogenic H2 and carbon monoxide production with an impure carbon monoxide expander

A process for obtaining purified carbon monoxide from a gaseous mixture consisting essentially of hydrogen and carbon monoxide and one or more additional impurities to be removed by one or more vapor-liquid separation devices, comprising the steps of :

• (a) providing a feed stream of the gaseous mixture;
• (b) cooling and partially condensing the feed stream of the gaseous mixture to partially separate the feed stream of the gaseous mixture into at least one hydrogen rich vapor substream and at least one carbon monoxide rich liquid substream;
• (c) substantially reducing the hydrogen concentration of at least a portion of at least one of the at least one carbon monoxide rich liquid substreams;
• (d) withdrawing a first and a second substream from any one of the at least one carbon monoxide rich substreams;
• (e) passing the first substream through a first expansion valve to let down the pressure in the first substream to a pressure nominally the same as that of a first one of the one or more vapor-liquid separation devices downstream;
• (f) vaporizing the first substream using a heat exchange device subsequent to passing the first substream through the first expansion valve, and prior to introduction of the first substream into any downstream vapor liquid-separation device;
• (g) vaporizing the second substream using a heat exchange device to produce a third substream at a pressure substantially above that of the first one of the one or more vapor-liquid separation devices;
• (h) passing the third substream through a work extraction device to provide a substantial portion of all refrigeration for cooling for the process;
• (i) subsequently feeding the third substream to the first one of the one or more vapor-liquid separation devices;
• and
• (j) withdrawing substantially purified carbon monoxide from any one or more of the one or more vapor-liquid separation devices.

An apparatus for obtaining purified carbon monoxide from a gaseous mixture consisting essentially of hydrogen and carbon monoxide and one or more additional impurities to be removed by one or more vapor-liquid separation devices downstream, the apparatus comprising:

• (a) means for providing a feed stream of the gaseous mixture;
• (b) means for cooling and partially condensing the feed stream of the gaseous mixture to partially separate the feed stream of the gaseous mixture into at least one hydrogen rich vapor substream and at least one carbon monoxide rich liquid substream;
• (c) means for withdrawing a first and a second substream from any one or more of the at least one carbon monoxide rich substreams;
• (d) a first expansion valve through which the first substream is passed, adapted to let down the pressure in the first substream to a pressure nominally the same as that of a first one of the one or more vapor-liquid separation devices downstream;
• (e) a heat exchange device for vaporizing the second substream adapted to produce a third substream at a pressure substantially above that of the first one of the one or more vapor-liquid separation devices;
• (f) a work extraction device adapted to pass the third substream therethrough and adapted to provide a substantial portion of all refrigeration for cooling for the process;
• (g) means adapted to feed the third substream to the first one of the one or more vapor-liquid separation devices downstream of the work extraction device;
• and
• (h) means to withdraw substantially purified carbon monoxide from any one or more of the one or more vapor-liquid separation devices.

An apparatus for obtaining purified carbon monoxide from a gaseous mixture consisting essentially of hydrogen and carbon monoxide and one or more additional impurities to be removed by one or more vapor-liquid separation devices downstream, comprising:

• (a) means for providing a feed stream of the gaseous mixture;
• (b) means for cooling and partially condensing the feed stream of the gaseous mixture to partially separate the feed stream of the gaseous mixture into at least one hydrogen rich vapor substream and at least one carbon monoxide rich liquid substream;
• (c) means for substantially reducing the hydrogen concentration of at least a portion of at least one of the at least one carbon monoxide rich liquid substreams,
• (d) means for withdrawing a first and a second substream from any one of the at least one carbon monoxide rich substreams;
• (e) a first expansion valve through which the first substream is passed to let down the pressure in the first substream to a pressure nominally the same as that of a first one of the one or more vapor-liquid separation devices downstream;
• (f) a heat exchange device for vaporizing the first substream downstream of the first expansion valve, and upstream of any downstream vapor liquid-separation devices;
• (g) a heat exchange device for vaporizing the second substream to produce a third substream at a pressure substantially above that of the first one of the one or more vapor-liquid separation devices;
• (h) a work extraction device adapted to pass the third substream therethrough to provide a substantial portion of all refrigeration for cooling for the process;
• (i) means to feed the third substream to the first one of the one or more vapor-liquid separation devices;
• and
• (j) means for withdrawing substantially purified carbon monoxide from any one or more of the one or more vapor-liquid separation devices.