Patent ID: 6578377
Filing Date: 2003-06-17
Classification: F25J,Y10S

Abstract:
A method for the recovery of hydrogen and carbon monoxide from a feed gas mixture containing hydrogen, carbon monoxide, methane, and hydrocarbons heavier than methane, which method comprises:(a) separating the feed gas mixture containing hydrogen, carbon monoxide, methane, and hydrocarbons heavier than methane to yield an intermediate feed stream depleted in hydrocarbons and a reject stream enriched in hydrocarbons heavier than methane; (b) separating the intermediate feed stream in a cryogenic separation system to yield a hydrogen-rich overhead product stream and one or more intermediate streams enriched in carbon monoxide and methane, wherein the separation system includes an absorption column refluxed with a methane-rich liquid reflux stream; (c) introducing the one or more streams enriched in carbon monoxide and methane into a cryogenic distillation system and withdrawing therefrom a carbon monoxide-enriched overhead product stream and a liquid bottoms stream enriched in methane; and (d) utilizing at least a portion of the liquid bottoms stream enriched in methane in (c) to provide the methane-rich liquid reflux stream in (b).