Syngas production by catalytic steam gasification of municipal solid waste in fixed-bed reactor

Abstract

The catalytic steam gasification of municipal solid waste for syngas production was conducted in a lab-scale fixed-bed reactor. The influence of the reactor temperature, steam to carbon ratio (S/C) and catalyst type (NiO/γ-Al2O3 or calcined dolomite) on the gas yield, gas composition, H2/CO molar ratio and carbon conversion efficiency were investigated. The results indicated that increasing reactor temperature resulted in greater gas production in the initial pyrolysis and improved endothermic reactions (gasification of char, catalytic cracking and reforming of tar), which resulted in the increase of syngas yield. Compared with MSW catalytic pyrolysis, the introduction of steam leads to more tar and char participating in steam gasification, which resulted in a rapid increase of syngas yield and carbon conversion efficiency. NiO/γ-Al2O3 catalyst revealed better catalytic performance for the cracking of tar than calcined dolomite. The highest H2 content (54.22%) and gas yield (1.75N m3/kg) were achieved at 900°C, S/C being 2.41 with NiO/γ-Al2O3 as catalyst.