The present invention provides a method and
system for efficiently producing
hydrogen that can be supplied to a fuel
cell. The method and
system of the present invention produces
hydrogen in a reforming reactor using a
hydrocarbon stream and
water vapor stream as reactants. The
hydrogen produced is purified in a hydrogen separating membrane to form a retentate
stream and purified hydrogen stream. The purified hydrogen can then be fed to a fuel
cell where electrical energy is produced and a fuel
cell exhaust stream containing
water vapor and
oxygen depleted air is emitted. In one embodiment of the present invention, a means and method is provided for recycling a portion of the retentate stream to the reforming reactor for increased hydrogen yields. In another embodiment, a
combustor is provided for combusting a second portion of the retentate stream to provide heat to the reforming reaction or other reactants. In a preferred embodiment, the
combustion is carried out in the presence of at least a portion of the
oxygen depleted air stream from the fuel cell. Thus, the
system and method of the present invention advantageously uses products generated from the system to enhance the
overall efficiency of the system.