Hydrogen-rich gas from catalytic steam gasification of municipal solid waste (MSW): Influence of steam to MSW ratios and weight hourly space velocity on gas production and composition

Abstract

The present work deals with a study coupling experiments and modeling of catalytic steam gasification of municipal solid waste (MSW) for producing hydrogen-rich gas or syngas (H 2 + CO) with calcined dolomite as a catalyst in a bench-scale downstream fixed bed reactor. The influence of steam to MSW ratios (S/M) on gas production and composition was studied at 900 °C over the S/M range of 0.39–1.04, for weight hourly space velocity (WHSV) in the range of 1.22–1.51 h −1. Over the ranges of experimental conditions examined, calcined dolomite revealed better catalytic performance at the presence of steam. H 2 and CO 2 contents increased with S/M increasing, while CO and CH 4 contents decreased sharply, the contents of CH 4, C 2H 4 and C 2H 6 were relatively small, and the influence of S/M was insignificant. The highest H 2 content of 53.22 mol %, the highest H 2 yield of 42.98 mol H 2/kg MSW, and the highest H 2 potential yield of 59.83 mol H 2/kg MSW were achieved at the highest S/M level of 1.04. Furthermore, there was a good agreement between the experimental gas composition and that corresponding to thermodynamic equilibrium data calculated using GasEq model. Consequently, a kinetic model was proposed for describing the variation of H 2 yield and carbon conversion efficiency with S/M during the catalytic steam gasification of MSW. The kinetic model revealed a good performance between experimental results and the kinetic model.