Bench-scale methanol autothermal reformer for distributed hydrogen production

摘要

A bench-scale methanol autothermal reformer (ATR) for distributed proton exchange membrane fuel cell (PEMFC) power system has been developed. A coating of ZnO-Cr2O3/CeO2-ZrO2 mixed oxides on ceramic honeycombs was employed as the reforming catalyst. In order to avoid non-uniform distribution of the reactants at the inlet of the reforming catalyst bed, a distributor has been designed by computational fluid dynamics (CFD) simulation. Thus, uniform distribution of the reactants can be achieved, which can lead to a good performance of the reformer. Based on the optimized reformer, a fuel processor comprised of an ATR unit, a water gas shift (WGS) unit, a CO preferential oxidation (PROX) unit and a fuel evaporator unit has been developed and successfully integrated with a 75kWe class PEMFC stack. The test shows that 120 Nm~3 h~(-1) H2-rich reformate can be provided by the methanol fuel processor, with 53 vol% H2 and less than 20ppm CO content, and the peak power output of the PEMFC system can attain 75.5 kWe during the 3-h operation of the integrated system. By using the anode offgas from the PEMFC stack to evaporate the fuel, the lower heating value (LHV) efficiency of the fuel processor can reach 96.5%.