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In order to improve the calorific value and reducibility of the syngas produced by traditional coal gasification technology, and to solve the problem of high cost of heat source in coal gasification, this paper proposes to use high-temperature copper slag as the heat carriers and catalyst for coal gasification, and CaO as the CO2 adsorbent during the coal gasification reaction. In this way, the proportion of H2 in the syngas gas can be increased, and the coal gasification reaction can be improved. In the experiment, the samples with different ratios were fully mixed, and then thermogravimetric experiment and gasification experiment were carried out. Through research, the following rules were found. The use of high-temperature copper slag as the heat source and catalyst in coal gasification can lead to a 20% increase in the final weight loss rate. Additionally, when CaO is used as the CO2 adsorbent during the coal gasification reaction, a noticeable secondary weight loss occurs at around 600°C and can reach a maximum speed of 0.19%/min. The use of the C/S/CaO = 1/1/2 ratio can result in a maximum weight loss rate of 23%. Meanwhile, the C/S/CaO = 1/2/1 group has been shown to achieve a maximum weight loss speed of 0.5%/min, and the C/S/CaO = 1/1/1 group exhibits a maximum secondary weight loss speed of 0.32%/min. The samples after gasification experiment were analyzed by SEM, CaO produced clustered iron-based and porous structure on the surface of copper slag in gasification reaction. Based on the Coats-Redfern method, kinetics of gasification reaction is obtained, and the optimum fitting function is C2, mechanism functions didn't change with the variation of C/S/CaO. The research results suggest that CaO and copper slag can both enhance the coal gasification reaction. In addition, CaO is proven to be a more affordable and accessible CO2 adsorbent compared to other alternatives. [ABSTRACT FROM AUTHOR]

Abstract: A new concept that a heat recovery system from blast furnace (BF) slag which would generate hydrogen-rich gas was proposed and a continuous moving-bed biomass gasification reactor was designed to evaluate the feasibility. The influences of temperature and particle size of BF slag on gasification product distribution and gas characterization were discussed. The results show that BF slag demonstrated better catalytic performance in improving tar cracking, enhancing char gasification and reforming of hydrocarbons; higher BF slag temperature and smaller particles size can produce more light gases, less char and condensate; as temperature of BF slag being 1200 °C and its size below 2 mm, gas yield and H2 content achieved the maximum being 1.28 N m3/kg and 46.54%, respectively. [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]

Abstract: The catalytic steam gasification of pig compost (PC) for hydrogen-rich gas production was conducted in a fixed-bed reactor. The influence of the catalyst and reactor temperature on yield and product composition was studied at the temperature range of 700–850 °C, for weight hourly space velocity (WHSV) in the range of 0.30–0.60 h−1. The results indicate that the developed NiO on modified dolomite (NiO/MD) catalyst reveals better catalytic performance on the tar elimination and hydrogen yield than calcined MD or NiO/γ-Al2O3 catalyst. Meanwhile, the lower WHSV and higher reactor temperature can contribute to more hydrogen production and gas yield. Moreover, the char from catalytic steam gasification of PC has a highest ash content of 75.84% at 850 °C. In conclusion, pig compost is a potential candidate for hydrogen gas production through catalytic steam gasification technology. [Copyright &y& Elsevier]

Abstract: The catalytic steam gasification of pig compost (PC) for hydrogen-rich gas production was experimentally investigated in a fixed bed reactor using the developed NiO on modified dolomite (NiO/MD) catalyst. A series of experiments have been performed to explore the effects of catalyst, catalytic temperature, steam to PC ratio and PC particle size on the gas quality and yield. The results indicate that the NiO/MD catalyst could significantly eliminate the tar in the gas production and increase the hydrogen yield, and the catalyst lives a long lifetime in the PC steam gasification. Moreover, the higher catalytic temperature and smaller PC particle size can contribute to more hydrogen production and gas yield. Meanwhile, the optimal ratio of steam to PC (S/P) is found to be 1.24. [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: In the present study the catalytic steam gasification of MSW to produce hydrogen-rich gas or syngas (H2 +CO) with calcined dolomite as a catalyst in a bench-scale downstream fixed bed reactor was investigated. The influence of the catalyst and reactor temperature on yield and product composition was studied at the temperature range of 750–950°C, with a steam to MSW ratio of 0.77, for weight hourly space velocity of 1.29h−1. Over the ranges of experimental conditions examined, calcined dolomite revealed better catalytic performance, at the presence of steam, tar was completely decomposed as temperature increases from 850 to 950°C. Higher temperature resulted in more H2 and CO production, higher carbon conversion efficiency and dry gas yield. The highest H2 content of 53.29mol%, and the highest H2 yield of 38.60mol H2/kg MSW were observed at the highest temperature level of 950°C, while, the maximum H2 yield potential reached 70.14mol H2/kg dry MSW at 900°C. Syngas produced by catalytic steam gasification of MSW varied in the range of 36.35–70.21mol%. The char had a highest ash content of 84.01% at 950°C, and negligible hydrogen, nitrogen and sulphur contents. [Copyright &y& Elsevier]