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.