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The tail gas with relatively high calorific value, generated from the depleted reduction of copper slag, can be used as fuel for gas turbines. In this study, the flame speed calculation module in PREMIX of CHEMKIN was used to simulate the combustion characteristics of the tail gas after sulfide removal, the effects of equivalence ratio, gas preheating temperature, and the CO2 concentration on the flame propagation speed and the flame combustion temperature were mainly investigated. Results show that the flame propagation speed and the flame combustion temperature increase continuously with the increase in preheating temperature, while it decreases continuously with the increase in CO2 concentration. Additionally, the peak flame combustion temperature appears at an equivalent ratio of 1.1, while the peak flame propagation speed appears at an equivalent ratio of 2.0, which indicates that the flame combustion temperature is not the main factor affecting flame propagation speed for tail gas.

In this experiment, photocatalysic material ,which is magnetic, photoluminesce and has superior light absorbing mesoporous, was synthesized by sol-gel method with tetrabutyl titanate, zinc acetate, stannic chloride , antimonic chloride and ferric nitrate as precursors, and tri-blocked copolymer F127 as the template.Based on the experiment results, when the annealing temperature is at 550°C, the annealing time is 120min , the doping amount of Zn is 4.0at%. These produced samples were shown to have superior luminescence and UV-vis light absorbance. When the weight of template was set to 1.5g, the obtained photocatalysic materials, indicated that their porous mainly distributed within 1.2nm to 4.7nm and their specific surface areas were larger than 110m2/g, and had excellent absorption properties.

Low breakdown electric field ZnO–Bi2O3–TiO2–Co2O3–MnO2 (ZBTCM) varistor ceramics doped with various amounts of B2O3 were prepared by the solid-state reactions. The sintering temperature was 900 °C, lower than the melting point of pure silver. The microstructural features and electrical properties were investigated by XRD, SEM and a capacitance meter. The results show that B2O3 is not only a sintering additive, but also an electrical property improver. ZBTCM based varistors with breakdown field of 131.25 V/mm, nonlinear coefficient (α) of 39.13 and leakage current density (JL) lower than 2.5 µA/mm2 were obtained by doping 1 wt% B2O3 sintered at 900 °C. [ABSTRACT FROM AUTHOR]

LaMnO3 with perovskite structure is a SCR de-NOx catalyst with good performance at low temperatures. In this paper, the SCR reaction process on the 010 surface of LaMnO3 catalyst was studied by DFT method, to guide the development of catalysts and their effective application. The results obtained through research indicate that both E-R and L-H mechanisms exist on the catalyst surface. The NH3 molecule can be absorbed on L acid and then oxidized by lattice oxygen to form NH2. Then, NH2 can react with the NO molecule to form NH2NO and decompose to N2 and H2O. The NH3 can also be absorbed with hydroxyl to form NH4+, it can also react with NO to form NH2NO and then decompose. The NH4+ also can react with NO3− which is formed by NO oxidized when O2 is present, to participate in the rapid SCR process. [ABSTRACT FROM AUTHOR]

In this study, waste engine oil (WEO) was used as catalyst for co-pyrolysis with waste tires (WT) to increase the heat transfer efficiency between tire particles. The synergetic effects during co-pyrolysis process of WT and WEO were investigated via thermogravimetric analyzer. Co-pyrolysis of different mixing ratios blends were performed in a self-made tube furnace at 500℃ to explore the effect on product distribution. The compositions of products were determined by FTIR, Py-GC/MS, and BET. TG and DTG curves of mixture demonstrate that WEO could change the pyrolysis process of WT significantly. The main pyrolysis temperature is reduced by 50℃. The conversion of pyrolysis oil increased, and the conversion of char decreased with the addition of WEO. The yield of H2 and D-limonene increased by 5.6% and 1.85%, respectively, when 20% WEO was added. Our work gives insight into the co-pyrolysis of WT and WEO, and provides a novel route of WT pyrolysis with high efficiency and quality. [ABSTRACT FROM AUTHOR]

Ceramic membranes based on naturally available materials are cost-effective and environmentally friendly alternatives to substitute Nafion™ 117 as separator in bioelectrochemical systems (BESs). In this study, copolymerization doped marine biomass-based (Ostrea gigas tnunb shell, OGTS; Sea sand, SS) ceramic membrane separators (CMSs) modified by Cu/Fe are synthesized by sintering. Modified CMSs exhibit superior chemical properties of acid and alkali resistance and thermodynamic stability. For CMS-ASO-Cu (CMS-Al 2 O 3 /SS/OGTS/Cu), Oxygen diffusion coefficient of 3.41 × 10−6 cm s−1 is 1.88 times higher than that of CMS-ASO-Fe (CMS-Al 2 O 3 /SS/OGTS/Fe). Proton transfer numbers of CMS-ASO-Cu is up to 0.62. Maximum power density 53.21 mW m−2 and current density 408.62 mA m−2 are achieved from CMS-ASO-Cu assisted BES, along with organic removal performance (COD >80%, NH 4 +-N > 80%, TP > 92%). Regeneration and antibacterial properties of the CMSs are confirmed by low-temperature sintering method and inhibition zone assay, ensuring the long-term, efficient and sustainable function of the C-BES. [Display omitted] • Copolymerization doped marine biowastes based ceramic membrane was synthesized. • Oxygen diffusion coefficient of CMS-ASO-Cu was 1.88 times of CMS-ASO-Fe. • Proton transfer numbers of CMS-ASO-Cu was up to 0.62. • Sustainable self-energy generation and organic removal were obtained in C-BES. • CMSs exhibited cyclic regeneration and antibacterial properties. [ABSTRACT FROM AUTHOR]

Abstract: Biomass micron fuel (BMF) produced from feedstock (energy crops, agricultural wastes, forestry residues and so on) through an efficient crushing process is a kind of powdery biomass fuel with particle size of less than 250μm. Based on the properties of BMF, a cyclone gasifier concept has been considered in our laboratory for biomass gasification. The concept combines and integrates partial oxidation, fast pyrolysis, gasification, and tar cracking, as well as a shift reaction, with the purpose of producing a high quality of gas. In this paper, characteristics of BMF air gasification were studied in the gasifier. Without outer heat energy input, the whole process is supplied with energy produced by partial combustion of BMF in the gasifier using a hypostoichiometric amount of air. The effects of equivalence ratio (ER) and biomass particle size on gasification temperature, gas composition, gas yield, low-heating value (LHV), carbon conversion and gasification efficiency were studied. The results showed that higher ER led to higher gasification temperature and contributed to high H2-content, but too high ER lowered fuel gas content and degraded fuel gas quality. A smaller particle was more favorable for higher gas yield, LHV, carbon conversion and gasification efficiency. And the BMF air gasification in the cyclone gasifier with the energy self-sufficiency is reliable. [Copyright &y& Elsevier]

Abstract Sludge gasification for the production of hydrogen-rich gas is a promising technology. In this paper, a pilot study on the hydrogen-rich gas production by sludge gasification using waste heat of blast furnace slag was carried out, and the mass and energy balance of gasification process using waste heat from blast furnace slag were evaluated. The results show that the higher the gasification temperature, the higher the hydrogen content in the gas. When the gasification temperature reaches 880 °C, the hydrogen content in the gas reaches the maximum,35.3%. The technology of sludge gasification combined with waste heat recovery of high furnace slag is feasible. Its efficiency of heat recovery can reach up to 64.35%, and the gasification efficiency and energy consumption ratio can reach to 42.30% and 3.67, respectively. Highlights • The sensible heat of molten slag was converted into hydrogen-rich gas gas. • A study on the sludge gasification using waste heat of BF slag was conducted. • The mass and energy balance of gasification were evaluated. [ABSTRACT FROM AUTHOR]

Abstract: The catalytic steam gasification of biomass was carried out in a lab-scale fixed bed reactor in order to evaluate the effects of particle size at different bed temperatures on the gasification performance. The bed temperature was varied from 600 to 900°C and the biomass was separated into five different size fractions (below 0.075mm, 0.075–0.15mm, 0.15–0.3mm, 0.3–0.6mm and 0.6–1.2mm). The results show that with decreasing particle size, the dry gas yield, carbon conversion efficiency and H2 yield increased, and the content of char and tar decreased. And the differences due to particle sizes in gasification performance practically disappear as the higher temperature bound is approached. Hydrogen and carbon monoxide contents in the produced gas increase with decreasing particle size at 900°C, reaching to 51.2% and 22.4%, respectively. [Copyright &y& Elsevier]

Abstract: NiO on modified dolomite (NiO/MD) catalysts were developed for hydrogen-rich gas production from steam gasification of municipal solid waste (MSW). The catalysts were prepared through deposition-precipitation method and characterized by various characterization methods. The activity of NiO/MD on the steam gasification of MSW was investigated in a lab-scale fixed bed. The results indicated that the catalysts could significantly eliminate the tar in the gas production and increase the hydrogen yield. In addition, higher temperature contributed to higher hydrogen production and gas yield, meanwhile, the optimal ratio of steam to MSW (S/M) was found to be 1.23. In the experimental conditions, the NiO/MD catalysts showed a good performance over a long lifetime test. [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 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: Based on composition and volume-mass properties of MSW (i.e., unit weight, void ratio, and water content), a new way for the breakage of the organic MSW is presented to effectively convert MSW to heat and fuel gas. A lab-scale shredder consisting of compaction and shredding chambers is designed and the breakage process of MSW in the shredder can be divided into three successive phases: deformation, further deformation, compressive shearing. The performances of the shredder, such as the effect of the rotor velocity and hydraulic pressure on product size distribution and specific energy are investigated. The results show that with hydraulic pressure the specific energy is reduced, and size distribution of product is finer. When hydraulic pressure is constant, the specific energy decreases with increasing rotor velocity, while the products size distribution is coarser. [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]

Abstract: In this paper, we report a simple hydrothermal method to synthesize barium strontium titanate (Ba1−x Sr x TiO3, x =0–1) dendrites without any templates. The obtained products were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), electron diffraction (ED), and energy-dispersive X-ray spectroscopy (EDX), respectively. All the samples were identified as cubic perovskite phase by XRD and the obtained Ba1−x Sr x TiO3 (x =0–1) dendrites were single-crystal. The formation process of Ba1−x Sr x TiO3 dendritic structures was also investigated. It is rational to expect that dendritic structures of other perovskite oxides may also be synthesized by this simple method. [Copyright &y& Elsevier]