| 摘要 |
Transport of water in a fuel cell system between a first gaseous stream having a higher concentration of water and a second gaseous stream having a lower concentration of water, by mass and heat transfer, is effected through a plurality of non-hydrophilic membranes in a membrane module, such that water uptake of the selective layer is less than 10 wt % measured at a water activity of 0.9 and at a temperature of 30° C.; the membrane has a minimum pressure-normalized water flux of 100 GPU at 50° C., and maintains an ideal selectivity of water over any remaining component in the gas mixture greater than 5 at 50° C. Water and heat are transferred from an exhaust stream from either the cathode or anode compartment of a PEM fuel cell into an incoming reactant stream, whether oxidant or fuel. Operation is at a temperature above 50° C. and water activity greater than 0.5 at that temperature; a membrane having a selectivity for water over any other component in the range from 50 to 500 at an operating temperature in the range from about 100° C. to 250° C. is preferred.
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