Compact selective oxidizer assemblage for a fuel cell power plant

摘要

A process gas selective oxidizer assemblage for use in a fuel cell power plant includes one or more catalyzed selective oxidizer process gas flow fields and one or more adjacent non-catalyzed heat exchanger process gas flow fields. The catalyzed selective oxidizer process gas flow fields may be formed with catalyzed pellets or with a monolithic catalyzed open cell foam component. The heat exchanger process gas flow fields are formed by non-catalyzed monolithic open cell foam components which have coolant fluid passages disposed therein. Planar metal sheets form a common wall between the selective oxidizer process gas flow fields and the heat exchanger process gas flow fields. The use of the open cell foam to form the heat exchanger process gas flow fields provides enhanced heat transfer between the reformate gas and the coolant fluid. The use of the foam components in both the heat exchange process gas flow fields and the selective oxidizer process gas flow fields enables the construction of a more compact and lighter weight selective oxidizer assemblage. The repeating components are placed side-by-side in the assemblage, so that one of the catalyzed process gas flow fields operates at a higher temperature than subsequent catalyzed process gas flow fields. The process gas enters the higher temperature catalyzed flow field after it is admixed with air that is injected into the system just prior to the higher temperature flow field. The process gas-air mixture flows through the first higher temperature catalyzed process gas flow field; thence through a non-catalyzed heat exchanger process gas flow field; thence through a lower temperature catalyzed process gas flow field; thence through another heat exchanger process gas flow field; and so on, until the selectively oxidized process gas exits the assemblage.