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Measurements were taken for a 35-ton-per-hour biomass-fired travelling grate boiler. Local mean concentrations of O(2), CO, SO(2) and NO gas species and gas temperatures were determined in the region above the grate. For a 28-ton-per-hour load, the mass ratios of biomass fly ash and boiler slag were 42% and 58%, the boiler efficiency was 81.56%, and the concentrations of NO(x) and SO(2) at 6% O(2) were 257 and 84 mg/m(3). For an 18-ton-per-hour load, the fuel burning zone was nearer to the inlet than it was for the 28-ton-per-hour load, and the contents of CO and NO in the fuel burning zone above the grate were lower.

Roasting is an important step in the pretreatment of biomass upgrading. Roasting can improve the fuel quality of biomass, reduce the O/C and H/C ratios in the biomass, and provide the biomass with a fuel quality comparable to that of lignite. Therefore, studying the structure and component evolution laws during biomass roasting treatment is important for the rational and efficient utilization of biomass. When the roasting temperature is 200–300 °C, the cellulose and hemicellulose in the biomass undergo a depolymerization reaction, releasing many monocyclic aromatic hydrocarbons with high reactivity. The proportion of monocyclic aromatic hydrocarbons in biomass roasting products can be effectively regulated by controlling the reaction temperature, residence time, catalyst, baking atmosphere, and other factors in the biomass roasting process. This paper focuses on the dissociation law of organic components in the pretreatment process of biomass roasting. [ABSTRACT FROM AUTHOR]

In order to determine the synergistic effects of the mixed additives of Fe and other catalysts on the yields and characteristics of bio-oil products, hydrothermal liquefaction (HTL) of pinewood sawdust (PW) was performed at 300 °C for 30 min (biomass/water mass ratio = 1:10) in the presence of metallic iron (Fe), other homogeneous/heterogeneous catalysts (Na 2 CO 3 , NaOH, FeSO 4 , MgO, Ru/C, FeS), as well as mixed additives. The results indicated that the metallic Fe could increase the yield and promote the degree of hydrodeoxygenation of bio-oil products. Noticeable synergistic effects on improving the bio-oil yields were found in the presence of mixed additives of Fe and an alkali catalyst (Na 2 CO 3 /NaOH) or FeS. The maximum bio-oil yield and the most energy recovery from bio-oil (81%) were obtained with Fe + Na 2 CO 3. In addition, the combination of Fe + Ru/C produced bio-oil with the highest carbon and hydrogen contents, the highest HHV (30.93 MJ/kg), as well as the lowest contents of oxygenated compounds and the largest amount of hydrocarbons. In summary, this work demonstrates the synergistic effects of the mixed additives of Fe and several catalysts (Na 2 CO 3 , FeS and Ru/C) in HTL of woody biomass, promoting both yields and quality of bio-oil products. • Mixed additives of Fe and other catalysts were applied during HTL of woody biomass. • Synergistic effects between Fe and catalysts on bio-oil yields/properties were found. • Maximum bio-oil yield and energy recovery was obtained with Fe + Na2CO3. • Hydrodeoxygenation of bio-oil was promoted by Fe + Ru/C or Fe + FeS. • Both yields and quality of bio-oil could be improved with Fe and suitable catalysts. [ABSTRACT FROM AUTHOR]

Developing carbon materials featuring both high accessible surface area and high structure stability are desirable to boost the performance of constructed electrochemical electrodes and devices. Herein, we report a new type of microporous carbon (MPC) derived from biomass waste based on a simple high-temperature chemical activation procedure. The optimized MPC-900 possesses microporous structure, high surface area, partially graphitic structure, and particularly low impurity content, which are critical features for enhancing carbon-based electrochemical process. The constructed MPC-900 symmetric supercapacitor exhibits high performances in commercial organic electrolyte such as widened voltage window up to 3 V and thereby high energy/power densities (50.95 Wh kg −1 at 0.44 kW kg −1 ; 25.3 Wh kg −1 at 21.5 kW kg −1 ). Furthermore, a simple melt infiltration method has been employed to enclose SnO 2 nanocrystals onto the carbon matrix of MPC-900 as a high-performance lithium storage material. The obtained SnO 2 -MPC composite with ultrafine SnO 2 nanocrystals delivers high capacities (1115 mAh g −1 at 0.2 A g −1 ; 402 mAh g −1 at 10 A g −1 ) and high-rate cycling lifespan of over 2000 cycles. This work not only develops a microporous carbon with high carbon purity and high surface area, but also provides a general platform for combining electrochemically active materials. [ABSTRACT FROM AUTHOR]

Abstract: In this paper the gasification of sawdust in an air cyclone gasifier was investigated to produce a high quality fuel gas with less tar. The effect of air to fuel ratio on the gasification characteristics was studied. The results indicate that as the air to fuel ratio varying from 0.23 to 0.35, the lower heating value of the produced gas is 4.5–5.7MJ/Nm3, the carbon conversion is 77.0–94.2%, the cold gas efficiency of the gasification system is 53.6–63.0%, while the tar content is 4.4–8.4g/Nm3. A detailed CFD model of a cyclone gasifier has been developed, based on the Fluent package. Models of sawdust pyrolysis and combustion of volatiles and char have been added to the standard model. The model provides information on the gas temperature in the gasifier and the composition of the outlet gas. [Copyright &y& Elsevier]

• Effect of Fe on HTL of cornstalk in ethanol–water mixed solvents was investigated. • Maximum oil yield of 50.46 wt% was obtained with Fe at the optimal conditions. • Hydrogenation and deoxygenation were promoted by Fe and mixed solvents. • Oil derived from Fe/mixed solvents mainly consist of phenolics, esters and hydrocarbons. • Effect of Fe in mixed solvents was primarily due to the reaction between Fe and water. In this article, effects of metallic Fe on biocrude oil production from cornstalk via hydrothermal liquefaction (HTL) in ethanol–water mixed solvents were investigated under various conditions. Experiments were conducted in single solvent of water or ethanol using Fe 3 O 4 catalyst to explore the role of metallic Fe in the liquefaction process. The physiochemical properties of the liquefaction products were comprehensively characterized by elemental analysis, GC–MS, FT-IR and XRD. The results showed that the maximum biocrude oil yield (approx. 50 wt%) and higher heating value (HHV) of 30.86 MJ/kg were obtained in ethanol–water mixed solvents (50/50, v/v) at 300 °C for 30 min with 10 wt% Fe loading. It was found that the presence of Fe also promoted the hydrogenation and deoxygenation of liquid products, obtaining biocrude oils mainly consisted of phenolic, ester and hydrocarbon compounds. The positive role of metallic Fe in HTL of biomass in ethanol–water mixed solvents, simultaneously improving the yield and quality of biocrude oil, was believed to be due to in-situ hydrogen formed from the reaction of metallic Fe and water, while the generated Fe 3 O 4 exhibited negligible catalytic effect in the process. [ABSTRACT FROM AUTHOR]