Design and Empirical Inquisition of Catalytic Combustor for Methanol Steam Reformer in HT PEM Fuel Cell Systems

Abstract

Steam reforming of methanol is a basic endothermic reaction. For which, a separate external system is required for generation of heat. The reaction speeds are controlled by operating temperature and heat transfer rate to the reactor. This operating temperature has a very narrow window of operation. It is therefore extremely important to have a system that generates controlled combustion based stable heat for providing required heat to reformer. A design of catalytic combustor was developed and analyzed for methanol steam reformer. The packed bed of combustion catalyst provides active sites for combustion of the methanol water mixture during start-up and later for combustion of anode exhaust gas (AEG) during normal operation. The combustion reactions and their thermodynamics were studied for commercial catalyst. System design was simulated using Engineering Equation Solver (EES) software for determining the quantity of air required for combustion of fuel as well as for dilution of gases to maintain a temperature of 573 K. The design was analyzed using ANSYS DISCOVERY LIVE for understanding the different operating condition(s) inside the combustor. It was also used to generate design of experiments to evaluate, build and demonstrate a catalytic combustor for on-board reformer for HT-PEM fuel cell system.