EFFECT OF H_2S ON MCFC 10KW-STACK PERFORMANCE

摘要

The conversion of coal, biomass and RDF(refuse-derived fuel) etc. by means of gasification into a fuel suitable for a high temperature fuel cell has recently received more attention as a potential substitute for fossil fuels in electric power production. However, combining the gasification with a high temperature fuel cell (Molten Carbonate Fuel Cell) raises many questions with regard to gas quality and impurities. We have paid attention to H_2S impurity contained in fuel gas and investigated the effect of H_2S on MCFC performance by operating a 10kW-class stack. The experimental results show the H_2S tolerable concentration to MCFC performance decreases with the decrease of H_2 concentration in fuel gas. A reason for this H_2S tolerance is due to the inhibition for shift reaction (H_2O + CO → H_2 + CO_2) by H_2S adsorption to anode. This inhibition by H_2S adsorption decreases the capability of high temperature fuel cell to utilize CO as a fuel.