Patent classifications
B01D2311/106
Enhanced hydrogen recovery utilizing gas separation membranes integrated with pressure swing adsorption unit and/or cryogenic separation system
Processes and systems for recovering hydrogen include feeding a gas stream, comprising hydrogen and additional gases, to a pressure swing adsorption (PSA) system and feeding a membrane permeate stream comprising hydrogen to the PSA system. In the PSA system, a portion of the hydrogen is separated from the additional gases to recover a hydrogen product stream and a PSA tail gas stream comprising unseparated hydrogen and the additional gases. The PSA tail gas stream is fed to a membrane separation unit for separating hydrogen from the additional gases and to recover (i) the membrane permeate stream comprising hydrogen fed to the PSA system and (ii) a membrane tail gas stream comprising the additional gases. Processes and systems herein may additionally include a refrigeration system for partially condensing one or both of the feed gas stream and the PSA tail gas stream, enhancing the efficiency of the membrane separation unit.