A fuel cell system including a fuel reforming processor having a catalyst therein
constructed and arranged to produce a reformate stream including hydrogen and carbon
monoxide, a water gas shift reactor downstream of the fuel reforming processor
and wherein the water gas shift reactor includes a catalyst therein constructed
and arranged to reduce the amount of carbon monoxide in the reformate stream, a
preferential oxidation reactor downstream of the water gas shift reactor and wherein
the preferential oxidation reactor includes a catalyst therein constructed and
arranged to preferentially oxidize carbon monoxide into carbon dioxide and to produce
a hydrogen-rich stream, and a fuel cell stack downstream of the preferential oxidation
reactor constructed and arranged to produce electricity from the hydrogen-rich
stream, a first direct water vaporizing combustor constructed and arranged to combust
fuel producing a high-temperature fuel combustion byproducts exhaust and to produce
steam from water sprayed into the combustion byproduct exhaust and wherein the
first direct water vaporizing combustor is plumbed to the fuel reforming reactor
to charge steam therein, and a second direct water vaporizing combustor constructed
and arranged to combust fuel to produce a high-temperature fuel combustion byproduct
exhaust and to produce steam from water sprayed into the fuel combustion byproduct
exhaust and wherein the second direct water vaporizing combustor is plumbed to
the water gas shift reactor to charge steam therein.