LOW TEMPERATURE FUEL CELL POWER PLANT OPERATION

摘要

A fuel cell power plant system (22) includes the ability to operate an enthalpy recovery device (40) even under old conditions. A bypass arrangement allows for selectively bypassing one or more portions of the recovery device under selected conditions. In one example, the enthalpy recovery device (40) is completely bypassed under selected temperature conditions to allow the device to freeze and then later to be used under more favorable temperature conditions. In another example, the enthalpy recovery device (40) is selectively bypassed during a system startup operation. One example includes a heater (60) associated with the enthalpy recovery device (40). Another example includes preheating oxidant supplied to one portion of the enthalpy recovery device (40).