Study On A Mini-reformer Coupling Exothermal With Endothermal Catalytic Reaction For Hydrogen Production

The aim of this paper is to develop a low cost, compact and efficient mini-reformer, which can provide reforming gas with high hydrogen concentration, low CO composition to the100We proton exchange membrane fuel cell(PEMFC). Further more, the system integration of hydrogen and fuel cell is realized to provide practical technical route.According to the asymmetric coupling of the heat exchanger design concept, the catalytic combustion and methanol steam reforming was coupled in the mini-reformer, and different particle metal catalysts were filled in each reaction chamber, and metal fin was also filled inside to enhance the heat conduction. A series experiments have been carried out to obtain the temperature distribution and the optimum operation conditions, the experimental results are analyzed and discussed. The results achieved were valuable for the design and optimization of the mini-reformer.A model describing the reaction process in the mini-reformer was derived using a three-dimensional numerical model countercurrent flow arrangement. Temperature distributions in different chambers and materials composition distribution in reforming chamber have been calculated. Theoretical predictions of the temperature distribution in reformer were in good agreement with experimental results.Base on the experiment and the CFD simulation results, a mini-reformer contain one rforming chamber, one water gas shift reaction chamber, one preheating chambers and one combustion chamber was successfully fabricated. It can be started-up at room temperature by the combustion of hydrogen. The effects of reaction temperature, methanol gas space velocity(GSV) and ratio of water to methanol on reforming reaction were investigated, and the stability of reformer was also studied under various operation conditions. Furthermore, the integrated reformer which can supply reformed gas at the maximum flow rate of90L/hr has been integrated with a miniature fuel cell, the small power system can produce continuous power more than100W.