Enhancement of the quality of syngas from catalytic steam gasification of biomass by the addition of methane/model biogas

Abstract In this study, methane and model biogas were added during the catalytic steam gasification of pine to regulate the syngas composition and improve the quality of syngas. The effects of Ni/γ-Al 2 O 3 catalyst, steam and methane/model biogas on H 2 /CO ratio, syngas yield, carbon conversion rate and tar yield were explored. The results indicated that the addition of methane/model biogas during biomass steam gasification could increase the H 2 /CO ratio to about 2. Methane/model biogas, steam and Ni/γ-Al 2 O 3 catalyst significantly affected the quality of syngas. High H 2 content syngas with H 2 /CO ratio of about 2, biomass carbon conversion >85% and low tar yield was achieved under the optimum condition: S/C  = 1.5, α  = 0.2 and using Ni/γ-Al 2 O 3 catalyst. According to ANOVA, methane and catalyst were the key influencing factors of the H 2 /CO ratio and syngas yield, and the tar yield mainly depended on the Ni/γ-Al 2 O 3 catalyst. Biogas, as a more environmentally friendly material than methane, can also regulate the composition of syngas co-feeding with biomass.