Patent ID: 7763086

Claim:
A hydrogen generation system comprising: a fuel reforming reactor generating a hydrogen-rich reformate gas at a temperature greater than 150 C; a pressure swing adsorption (PSA) hydrogen purification unit that separates the reformate gas into a relatively pure hydrogen stream and an off-gas stream; a catalytic reactor down stream of the PSA unit that converts carbon monoxide (CO) and hydrogen (H 2 O) contained in the relatively pure hydrogen stream into methane (CH 4 ) and water vapor (H 2 O); a first secondary purification stage downstream of the PSA unit and the catalytic reactor, the first secondary purification stage having a first water adsorbent material bed that adsorbs the H 2 O and a first hydrogen absorbent or adsorbent material bed downstream of the first water adsorbent material bed; and a second secondary purification stage downstream of the PSA unit and the catalytic reactor connected in parallel to the first secondary purification stage, the second secondary purification stage having a second water adsorbent material bed that adsorbs the H 2 O and a second hydrogen absorbent or adsorbent material bed downstream of the second water adsorbent material bed; wherein the relatively pure hydrogen stream is selectably connected to one of the first secondary purification stage and the second secondary purification stage.