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Abstract: Syngas production from pyrolysis of municipal solid waste (MSW) with calcined dolomite as catalysts, has been investigated in a bench-scale downstream fixed-bed reactor over the temperature range of 750–900°C. The influence of weight hourly space velocity (WHSV) and reactor temperature on product yields and gas composition were studied. Syngas production from pyrolysis of MSW varied in the range of 47–67mol%. The results indicated that the presence of calcined dolomite influenced greatly the product yields and gas composition in pyrolysis process, and revealed significant catalytic performance on increasing gas yield and decreasing oil yield and char yield compared to non-catalytic process. A higher temperature resulted in a higher conversion of MSW into syngas production with a significant increase of H2 and CO contents. Meanwhile, syngas from MSW pyrolysis is highly desirable as feedstock for Fischer–Tropsch synthesis for the production of transportation fuels, also can be directly used as a MHV fuel with lower heating value of ∼13.87MJ/Nm3. [Copyright &y& Elsevier]

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 (H2 +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 1.22–1.51h−1. Over the ranges of experimental conditions examined, calcined dolomite revealed better catalytic performance at the presence of steam. H2 and CO2 contents increased with S/M increasing, while CO and CH4 contents decreased sharply, the contents of CH4, C2H4 and C2H6 were relatively small, and the influence of S/M was insignificant. The highest H2 content of 53.22mol%, the highest H2 yield of 42.98mol H2/kg MSW, and the highest H2 potential yield of 59.83mol H2/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 H2 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. [Copyright &y& Elsevier]

Abstract: The catalytic steam gasification of waste polyethylene (PE) from municipal solid waste (MSW) to produce syngas (H2 +CO) with NiO/γ-Al2O3 as catalyst in a bench-scale downstream fixed bed reactor was investigated. The influence of the reactor temperature on the gas yield, gas composition, steam decomposition, low heating value (LHV), cold gas efficiency and carbon conversion efficiency was investigated at the temperature range of 700–900°C, with a steam to waste polyethylene ratio of 1.33. Over the ranges of experimental conditions examined, NiO/γ-Al2O3 catalyst revealed better catalytic performance as a view of increasing product gas yield and of decreasing char and liquid yields in the presence of steam. Higher temperature resulted in more H2 and CO production, higher carbon conversion efficiency and product gas yield. The highest syngas (H2 +CO) content of 64.35mol%, the highest H2 content of 36.98mol%, and the highest CO content of 27.37mol%, were achieved at the highest temperature level of 900°C. Syngas produced with a H2/CO molar ratio in the range of 0.83–1.35, was highly desirable as feedstock for Fischer–Tropsch synthesis for the production of transportation fuels. [Copyright &y& Elsevier]

Abstract: The catalytic steam gasification of biomass was carried out in a lab-scale fixed bed reactor in order to evaluate the effects of temperatures and the ratio of steam to biomass (S/B) on the gasification performance. The bed temperature was varied from 600 to 900 and the S/B from 0 to 2.80. The results show that higher temperature contributes to more hydrogen production. The introduction of steam improves the dry gas yield and carbon conversion efficiency. But excessive steam will lower hydrogen content and degrade fuel gas quality. As S/B are 2.10, the hydrogen content reach the maximum, up to 52.7%. [Copyright &y& Elsevier]