Experimental study on steam co-gasification of biomass/municipal solid waste (MSW) for H2-rich gas production

Abstract

Co-gasification of biomass and MSW represents an effective approach for the waste recovery and carbon emission reduction. The optimal conditions for biomass/MSW gasification is important in planning large–scale setups. Here, an experimental study was conducted in a lab-scale fluidized bed gasification system at various temperatures (700–850 °C), steam/feedstock ratio (S/F: 0.25–1.0), MSW mixing ratio (MMR: 0–100 %) and Ni contents (0–20 %) for H₂-rich gas production. Ni/dolomite was selected as an in-bed material for tar reformer and solid absorption. The motivation of this work is to find out the suitable conditions for obtaining high-quality and low-tar syngas appropriate to use in engineering applications. Compared with calcined dolomite, Ni/dolomite revealed better catalytic activity in terms of tar modification. The results showed that there is an optimal value for Ni content. Increasing Ni content from 0 to 15 % resulted in more H₂ production, higher gas yield (Y_g) and lower tar yield (Y_T). However, a slight reduction in the catalytic activity of Ni/dolomite with a further increase of Ni content from 15 % to 20 % was observed, probably due to a slight coke deposition on Ni/dolomite catalyst for Ni content> 15 %. With the growth of MSW content, Y_G showed a slight variation due to a slight change in carbon content of biomass-MSW mixtures at high MMRs.