Patent ID: 7976992

Claim:
In a PEM fuel cell power plant having fuel cells ( 4 ) that produce a humidified gaseous reactant effluent stream during power plant operation, a reactant effluent stream processing system comprising: a) ducts ( 30 ) configured to flow the humidified gaseous reactant effluent stream away from said fuel cells; b) a condenser ( 16 ) for condensing water out of the humidified gaseous reactant effluent stream so as to produce a condenser effluent stream which contains gas and condensed water; c) a separator ( 20 ) configured for separating water from gas in the condenser effluent stream; and d) a vent ( 24 ) configured for venting gas from said separator, said vent including a layer of antifreeze ( 40 ) through which gas in the separator can pass to ambient surroundings.