COMPACT REGENERABLE SULFUR SCRUBBER FOR PHOSPHORIC ACID FUEL CELLS

A BENCH SCALE TEST PROGRAM IS PROPOSED TO EVALUATE USE OF CUO/ZNO DESULFURIZATION SORBENTS FOR THE NOT REGENERABLE SULFUR REMOVAL FROM LOGISTIC HYDROCARBON FUELS REFORMED FOR USE IN DISPERSED PHOSPHORIC ACID FUEL CELL POWER PLANTS. AN EFFICIENT REGENERABLE DESULFURIZATION PROCESS OPERATING WITHIN THE TEMPERATURE RANGE OF 450 TO 650 DEG C WOULD PROVIDE CONSIDERABLE FLEXIBILITY FOR INSERTION INTO THE FUEL PROCESSING BETWEEN HYDRODESULFURIZATION AND HYDROCARBON REFORMING STAGES (HIGH TEMPERATURE STEAM REFORMING, AUTOTHERMAL REFORMING OR PARTIAL OXIDATION) OR BETWEEN THE HYDROCARBON REFORMING STAGE AND THE SHIFT CONVERSION STATES. SULFUR REMOVAL FROM THE PROCESS STREAMS TO LOW LEVEL (<<10 PPM H2S) IS ESSENTIAL FOR PROTECTION OF BOTH THE LOW TEMPERATURE SHIFT CORROSION CATALYST AND THE FUEL CELL ANODE. DEMONSTRATION HAS ALREADY BEEN ESTABLISHED THAT SECOND STATE HOT DESULFURIZATION OF COAL GASES WITH AIR AND AIR/STEAM OXIDATION REGENERATION MIXED CUO/ZNO SORBENTS PROVIDE AN EFFICIENT SULFUR REMOVAL STAGE FOR MOLTEN CARBONATE FUEL CELL APPLICATIONS.