Numerical simulation of a combined system of ethanol steam reforming and HT-PEM fuel cell

Abstract

ABSTRACT In the present study, the integrated system of ethanol steam reforming (ESR) and the high temperature polymer electrolyte membrane fuel cell (HT-PEMFC) is simulated using ASPEN Plus™ and MATLABTM, respectively, in order to develop a clean energy technology. In ESR section, an ethanol steam reforming reactor (ESRR) is simulated using the R-Plug reactor based on a mechanistic kinetic model instead of a simple R-Gibbs reactor to consider the complexity of ESR reactions and a water gas shift reactor (WGSR) using the R-Equilibrium reactor modules of ASPEN Plus™ to obtain the optimal hydrogen production conditions. The simulated results show good agreement with the experimental observations for hydrogen yield, and it is found that the yield of hydrogen increases with increase in temperature and S/E ratio with minimal effect of pressure on it. Based on ESR section simulations, the optimal operating conditions of 923 K with S/E ratio of 4 under atmospheric condition are selected for ESRR and 423 K for WGSR to maximize hydrogen yield and minimize CO amount, respectively. The ESR section product is found to produce the fuel-cell-grade hydrogen [0.25 mole % of CO (dry, CO2-free basis) with the remaining as hydrogen] to be used in the HT-PEMFC section. The performance of HT-PEMFC section combined with ESR section is analyzed using MATLABTM, for the operating parameters like temperature, pressure, and feed CO concentration.