Recovery from a Mixed Hydrogen-NG Network

CMSMs meet the PEM fuel cell leqrrirement of H2 prrrity mote than 95%, even when the feed hydrogen concentration is as low as 5 mol%. 

The lowest cost is obtained for the low H2 recovery from a feed of 40 bar and 30 mol% hydrogen. 

Product H2 purity decreased as the H2 recovery increased. When the modttle is operated a 25°C, however, prrrity reqrriiement (H2 95 mol%) was met up to the recovery of 90%. This was not the case for the operating temperatiue of 90°C. 

The optimum permeate pressure decreased as H2 recovery increased and as feed pressure or feed hydrogen concerttration decreased. 

The cost of membrane influences the optimum permeate pressure. If the mem-braue costs more, the optimum permeate pressure becomes less. This is to iucrease the driviug force for the gas permeatiou aud reduce the membrane area requirement. 

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