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Steam gasification of pine sawdust over hematite was carried out in a decoupled dual loop gasification system. The system is composed of two parts, i.e. a fluidized bed gasifier and a moving bed reformer. Two parallel loops based on the above two parts were set up followed by a particles grading cyclone. The bed material in gasification loop was fine quartz sand while that in the reforming loop was the mixture of coarse hematite and quartz sand. The ratio of hematite to biomass, reforming temperature and steam to carbon ratio (S/C) were investigated. The results show that the above factors play crucial roles in biomass steam gasification. Higher reforming temperature promotes tar removal and water conversion while higher S/C increases H 2 /CO ratio and dry gas yield. At gasification temperature 750 °C and reforming temperature 700 °C, the tar yield of 4.2 g/Nm3 and 29.6 g/Nm3 have been obtained with hematite and quartz sand as bed material, respectively. Unlabelled Image • Reforming loop is investigated independently in a decoupled dual loop gasifier. • Hematite shows excellent tar removal effect as circulating bed material. • High tar removal effect is obtained in relative low temperature. [ABSTRACT FROM AUTHOR]

Abstract Energy access in Sub-Saharan Africa (SSA) remains a challenging issue at the midway point to the United Nations' development goals. From the perspective of energy efficiency and diversification of power-generation sources, this paper investigates the capacity of the wood-processing industry to contribute to the decentralised power generation by performing a techno-economic analysis of the use of wood residues for cogeneration. Using a survey performed in Cameroon as a case study, a biomass-fuelled cogeneration scheme and a model analysing its viability are proposed for the specific context of SSA. A sensitivity analysis indicates for a given process efficiency of the industry, the attractiveness of cogeneration as the processing capacity and feed-in tariffs of electricity increase. More specifically, the threshold of feed-in tariffs ensuring the economic viability of CHP in the sub-region is estimated at $0.15 per kWh for mills where the output capacities of sawn timber products are of 5000 cubic metre per annum and more. The power-generation potential from the primary processing of timbers in the sub-region is about 388 kWh per cubic metre of sawn wood, while the energy intensity of the sawing process is estimated at 132 kWh per cubic metre. Therefore, the industry can generate up to 2472 GWh of electricity in the three sub-regions of East, West and Central Africa if a total of US$ 2.5 billion is invested, allowing a substantial increase of 1% of the current electricity-generation capacity for the geographic location which has the most important forestry resources on the continent. Highlights • Wood-processing residues can contribute significantly to the distributed power generation in African forestry regions. • Energy patterns and the biomass feedstocks from wood-processing industries in Sub-Saharan Africa is comprehensively analysed. • The condensing-extraction steam turbine appears to be the most suitable technology for wood-fired CHP in Sub-Saharan Africa. • A model analysing the viability of industrial wood-fired CHP in the particular context of Sub-Saharan Africa is provided. • Key barriers to the development of waste-wood-fuelled CHP in Sub-Saharan Africa are identified. [ABSTRACT FROM AUTHOR]

European Commission is promoting the usage of renewable energy and the replacement of fossil fuels with biomass. Two-thirds of renewable energy will be derived by biomass by 2020 (European Commission. 2012. Roadmap 2050. DOI: 10.2833/10759). However, increasing need for biomass generates sustainability issues by land-use change. Biomass waste as biofuels do not affect land-use, therefore the sustainability potential is improved (Searchinger T, Heimlich R, Houghton RA, Dong F, Elobeid A, Fabiosa J, Tokgoz S, Hayes D, Yu T-H. 2008. Use of U.S. croplands for biofuels increases greenhouse gases through emissions from land-use change. Science. 319:1238-1240). However, biomass waste contaminates could release toxic VOCs, and also particulates and ash may contain non-VOCs such as heavy metals (Pitman RM. 2006. Wood ash use in forestry-a review of environmental impacts. Forestry. 79(5):563-588). This study investigates the VOC combustion emissions of low-grade lignocellulosic waste to determine the suitability wood wastes as bio-fuel. [ABSTRACT FROM AUTHOR]

In recent years, the world has witnessed a rapid rise in waste production and energy demand, which has increased interests in waste to energy processes, particularly the co-pyrolysis of wood and plastic waste. Nonetheless, for plastic waste, most research studies narrowly focus on polyolefins because of their abundance in waste streams and their high oil yields from pyrolysis. In this paper, we study the co-pyrolysis of non-polyolefins – polystyrene (PS) and polyvinyl chloride (PVC) – and poplar wood (PW), in order to investigate the synergistic effect of PS and PVC content on product yield, gas specie yield and heating value. The experiments were performed using a fixed-bed reactor, heated to 750  ° C at a rate of 20  ° C/min under nitrogen atmosphere. Our results show that PVC has a large positive synergy on char yield with a maximum value of 8 wt% at 30 wt% PVC content, whereas PS only showed a slightly positive synergy (2.5 wt% maximum). Concerning oil and gas production, PS provides a small synergy. However, PVC showed a significant positive synergy on oil yield with a maximum value of 11 wt% at 50 wt% PVC content, which was linked to a strong negative synergy in gas production. Regarding gas specie yields, the addition of PS led to positive synergies in the formation of H 2 , CH 4 , CO and CO 2 , although insignificant interactions were observed for C x H y compounds. Furthermore, by comparing the distribution of chloride species in the products of co-pyrolysis with PVC, using experimental and theoretical methods, we discovered that the negative synergy in HCl yield observed was mainly due to the dissolution of HCl in the water fraction of the condensed oil phase, rather than the formation of chlorinated organic compounds, as suggested in previous literature works. Our study therefore consolidates the understanding of the synergistic interactions between wood, PS and PVC co-pyrolysis, under conditions that favour gas production. [ABSTRACT FROM AUTHOR]

Biomass fast pyrolysis oils contain molecules having a large variety of chemical functions and a wide range of molecular weights (from several tens to several thousand grams per mole). The good knowledge of their complex composition is essential for optimizing the conversion of bio-oils to biofuels, thereby requiring powerful separation techniques. In this work, we investigate the interest of centrifugal partition chromatography (CPC) as a first dimension for the analysis of a bio-oil. A CPC method is proposed to separate oxygen containing compounds according to their partition coefficients in the solvent system. This approach is a powerful and easy-to-use technique that enables fractionation of a bio-oil at a semi-preparative scale, without any sample loss related to adsorption on the stationary phase. Collected fractions are then injected in liquid chromatography as a second dimension of separation. Contour plot representations of the CPC × LC separation are established to discuss the potential of this approach. These representations can be used as a veritable fingerprint in the comparison of different samples or samples at different steps of a conversion process but also as a powerful tool to identify new compounds and describe the entire composition of the bio-oil. [ABSTRACT FROM AUTHOR]

Abstract This study presents a real-time drying control system that was developed to control air drying of sawdust in a pneumatic conveying dryer to produce high-grade wood pellets in the range of the target moisture content (MC). The real-time drying control system was installed with moisture sensors to control the ON/OFF periods of the fuel (pellet) supply motor for the sawdust to generate the heat necessary to dry the sawdust to an optimum level of 15% moisture content for pelletizing. The results of the experiment and the simulation showed that the drying efficiency improved when a buffer was introduced instead of using a conventional system, and the average moisture content of the dried sawdust was measured to be about 12.4% in a pneumatic conveying dryer without buffer and about 14.7%–15.2% in the developed real-time drying control system. This study shows that the real-time drying control system could dry the sawdust to the targeted constant moisture content, and the buffer in the pneumatic conveying dryer could improve the drying efficiency according to an increase in the resident time of the sawdust. Highlights • A real-time drying control system was developed to control the air drying process for sawdust in a pneumatic conveying dryer. • Drying efficiency was improved when the buffer was present instead of the conventional system. • The real-time drying control system dries the sawdust with constant range compared to the initial moisture content. [ABSTRACT FROM AUTHOR]

The growing population poses serious threats not only to forests but also to the overall environment due to fuel and wood consumption used for various purposes. However, converting organic waste into fire bricks could be a useful step towards alternative energy sources. In the present study, fire bricks were prepared using organic waste i.e., cardboard, rice husk, saw dust, cow dung and newspapers. Firstly, the brick manufacturing materials were soaked in water in various ratios and converted into paste with mortar and pestle to make bricks. Secondly, the fire bricks were analyzed for gas emissions, burning time period, flue gas temperature and net efficiency. The results reveal that gas emissions were below the National Environmental Quality Standards (NEQS). Moreover, the results were also compared with a commonly used fuel wood (Vachellia karroo) to calculate the statistical variations for various parameters. Thus, the net efficiency range of fire bricks was from 39.7 to 58.9%, significantly higher than that of the fuel wood. The flue gas temperature varied from 230 to 430 °C. Therefore, the bricks were found to have high heat intensity, to be easy to use, and to have needed small space for their storage. Additionally, fire bricks are cost-effective compared to fuel wood. It is concluded that high quality and durable fire bricks can be made while using a combination of rice husk and newspapers (RHNP), rice husk and cardboard (RHCB), sawdust and cardboard (SDCB), cow dung and cardboard (CDCB), cow dung and newspapers (CDNP), sawdust and cow dung (SDCD) in a ratio of 2:3. It is due to all these benefits, that fire bricks were considered eco-friendlier in efficiency than fuel wood. [ABSTRACT FROM AUTHOR]

Hydrodeoxygenation (HDO) is effective for upgrading bio-oil to biofuel. However, the upgrading cost increased due to the high consumption of external hydrogen. In this paper, the hydrogen generated from cheap water using zinc hydrolysis for in situ bio-oil HDO was reported. The effect of different temperatures (200 °C, 250 °C and 300 °C) on bio-oil HDO over Pd/C catalyst was investigated in a batch reactor. The results show that 250 °C yielded biofuel with the highest heating value at 30.17 MJ/kg and the highest hydrocarbons content at 24.09%. Physicochemical properties including heating value, total acid number and chemical compositions of the produced biofuels improved significantly in comparison with that of the original bio-oil. [ABSTRACT FROM AUTHOR]

Uncertainties in quality and timely availability of feedstock are among major issues in planning an economically viable bioenergy enterprise. Reported studies in open literature on feedstock supply logistics are either the results of modeling or from laboratory scale investigation with limited usefulness to commercial operations. The objective of this research is to quantify the sensitivity of steam production rate in a commercial updraft gasifier to several critical feedstock quality attributes like moisture, ash, and particles size. The specific case study is a 7 MW thermal gasifier at the University of British Columbia that supplies process steam to campus facilities. The wood fuel is collected from a large number of urban waste wood sources, sorted, and blended in a recycling yard (depot) prior to delivery to the gasification plant. Several improvements in particle size uniformity, reduction in wood contamination with dirt, and dryness of the feedstock were made within a two-year period of recorded data (2013–2014). As a result, the overall percent of operating hours of the gasification plant increased from 75% to 94% while the average steam production increased by 30%. Most of the earlier variability in fuel properties was traced to the blending of dry fuel chips at a moisture content of 17% wet basis with a high moisture green wood at a moisture content of 40% wet basis. [ABSTRACT FROM AUTHOR]

The procedure and results of calculation of the thermodynamic and thermophysical properties of alternative fuel are given. [ABSTRACT FROM AUTHOR]

Sustainable use of wood may contribute to coping with energy and material resource challenges. The goal of this study is to increase knowledge of the environmental effects of wood use by analyzing the complete value chain of all wooden goods produced or consumed in Switzerland. We start from a material flow analysis of current wood use in Switzerland. Environmental impacts related to the material flows are evaluated using life cycle assessment-based environmental indicators. Regarding climate change, we find an overall average benefit of 0.5 tonnes carbon dioxide equivalent per cubic meter of wood used. High environmental benefits are often achieved when replacing conventional heat production and energy-consuming materials in construction and furniture. The environmental performance of wood is, however, highly dependent on its use and environmental indicators. To exploit the mitigation potential of wood, we recommend to (1) apply its use where there are high substitution benefits like the replacement of fossil fuels for energy or energy-intensive building materials, (2) take appropriate measures to minimize negative effects like particulate matter emissions, and (3) keep a systems perspective to weigh effects like substitution and cascading against each other in a comprehensive manner. The results can provide guidance for further in-depth studies and prospective analyses of wood-use scenarios. [ABSTRACT FROM AUTHOR]

The design and analysis of an integrated biomass gasification and PEMFC system to generate heat and power demand for residential applications are presented in this study. Two biomass gasification configurations using sawdust as a feedstock are considered: air–steam biomass gasification (AS-BG-PEMFC) and steam-only biomass gasification (SO-BG-PEMFC). The biomass processing consists of a biomass gasification which is used to produce H 2 -rich gas (syngas), followed by high- and low-temperature shift reactors and a preferential oxidation reactor. Pinch analysis is performed to evaluate and design a heat-exchanger network in the two biomass gasification systems. The remaining useful heat is recovered and employed for a reactant preparation step and for a heating utility system in a household. The simulation results indicate that the SO-BG-PEMFC generates syngas with a greater H 2 content than the AS-BG-PEMFC, resulting in higher fuel processor and electric efficiencies. However, the AS-BG-PEMFC provides a higher thermal efficiency because a high-temperature gaseous product is obtained, and more energy is thereby recovered to the system. The total heat and power efficiencies of the AS-BG-PEMFC and the SO-BG-PEMFC are 83% and 70%, respectively. The Sankey diagram of energy flows reveals that the performance improvement depends entirely on the utilization of useful energy in the exhaust gas. [ABSTRACT FROM AUTHOR]

In the paper was presented experimental installation for monitoring parameters of the wood briquettes combustion process. The combustion process depends on the share wood sawdust and the waste material from refining process of base oils and paraffin. This is waste material from technology process after solvent dewaxing. In order to improve the physical and chemical properties of base oils and paraffin, method of treatment with active clay is used for generating a certain amount of oily waste material called filter cake. In this work determination of optimum ratio between wood sawdust, oil filter cake and paraffin filter cake was done in order to obtain an alternative fuel (ecological briquette) that can be safely used from energy-environmental aspects in certain types of fire boxes. The paper presents results of experimental researches achieved by combustion of ecological briquettes in type fire box. The results showed that the oil filter cake and paraffin filter cake in proper ratio can be mixed with sawdust generating briquette that can be used as fuel in furnaces for central heating. This work also showed that the products of combustion process are not harmful to human life and working environment. After solvent dewaxing, in order to improve the physical and chemical properties of base oils and paraffin, method of treatment with active clay is used for generating a certain amount of oily waste material called filter cake. [ABSTRACT FROM AUTHOR]

The hydrothermal treatment is an established chemical-free process to modify wood, improving wood durability and technological parameters through its service life. During the hydro-thermolysis several reactions of wood components occur, releasing volatile and non-volatile compounds. Once the process is accomplished, solid residues below the wood load are formed and gaseous products are generated and collected as condensed water from the gas stream. In order to understand and characterize the industrial residues generated during the hydrothermal treatment of Pinus radiata D. Don, solid and liquid samples were analyzed. The results indicated structural and chemical differences among the evaluated residues. In case of the solid sample, a superior thermal stability (above 300 °C) was displayed, mostly formed by sugars and lignin derived compounds. In contrast, the liquid sample started to degrade at lower temperatures (around 200 °C) and predominantly was composed by a large amount of phenolic and volatile compounds. Moreover, this liquid fraction exhibited antioxidant activity (about 54%) against DPPH free radical. Furthermore, the principal products detected in the both residues by chromatographic analysis were furfural, guaiacol and syringol derivatives. [ABSTRACT FROM AUTHOR]

Technical risk and unfavourable project economics are often touted as barriers to successful waste-to-energy systems. Understanding feedstock behaviour, and how this impacts technology selection and operation, is a key aspect to addressing the technical risk component. In gasification systems, feedstock reactivity to CO 2 is one of the factors that are known to contribute significantly to feedstock behaviour. In this work, the reactivities of char samples from components of municipal solid waste (MSW) to CO 2 were characterised as part of a wider study into gasification behaviour of waste streams. As expected, gasification rates of wood waste and garden waste chars are comparable to those from other biomass fuels. The least reactive chars were found to be those produced from textiles and printing papers. There were two orders of magnitude differences in the rates of the least reactive and most reactive components, which has significance for our understanding of how the composition of the material in a waste gasifier changes with time. Furthermore, we demonstrated a good closure between calculated rates (based on properties of individual components) and rates measured for the entire MSW sample. This shows that this study has a broader applicability, and could be extended to estimate the gasification behaviour of MSW streams of different compositions in a range of gasification technologies. [ABSTRACT FROM AUTHOR]

Numerical modelling is widely used in industry for detailed understanding of the combustion process and for appropriate design and optimization of biomass/waste-fired boilers. This paper presents a numerical study of a 13 MW th waste wood-fired grate boiler, based on the coupled in-bed fuel conversion modelling and freeboard combustion modelling methodology. A 1D model is developed for the conversion of the waste wood in the fuel bed on the grate, providing the appropriate grate inlet condition for the 3D simulation of the freeboard region. Since part of the flue gas is recycled into the boiler as an innovative attempt to improve the boiler performance, a refined weighted-sum-of-grey-gases-model of greater accuracy is developed to better address the impacts of the elevated CO 2 and H 2 O vapour concentrations on radiative heat transfer in the boiler. The impacts of full buoyancy on the turbulent flow are also investigated. The temperature profiles at different ports in the furnace are measured to shed some light on the flow and combustion characteristics in the boiler and also to collect some in-flame data for modelling validation. The overall modelling strategy, the new sub-models and the use of recycled flue gas are all of great benefit or reference for modelling and design of grate-fired boilers. [ABSTRACT FROM AUTHOR]

Emulsification characteristics of bio-oils and diesel at various operating conditions are analyzed. Three different commercial emulsifiers (i.e., Span 80, Tween 80, and Atlox 4914) and four bio-oils from fast pyrolysis of wood wastes are studied. When the three emulsifiers are individually employed, the performance of the emulsifiers is characterized by the order of Atlox 4914 > Span 80 > Tween 80. Atlox 4914, consisting of the hydrophilic portion of PEG and the hydrophobic portion of poly alkyd resin, has a better performance. The HLB value of an emulsifier can be obtained by blending Span 80 and Tween 80 or Span 80 and Atlox 4914. The optimum HLB for the emulsification of bio-oils and diesel linearly increases with increasing the atomic O/C or H/C ratio, water content, and decreasing higher heating value (HHV) of bio-oil. The correlation of the optimum HLB and HHV provides the best result, which can be employed for practical emulsification operation between bio-oils and diesel and is conduce to reducing operation cost. The functional groups in the emulsifiers, bio-oils, and diesel are analyzed by a Fourier transform infrared spectroscopy (FTIR) to recognize the characteristics of emulsions. It is found that FTIR is a fast and effective tool to examine the stability and homogeneity of emulsified fuels, even though no stratification is observed. Accordingly, this developed method can be used to rapidly and precisely identify the performance of emulsification in industry. [ABSTRACT FROM AUTHOR]

This paper presents fuel molding technologies (PAS-i and PAS-r) with the participation of wood waste. These fuels are manufactured specifically for cement plants. The final product in the form of fuel derived from waste, meets the requirements of the recipient. In PAS-i fuel (Impregnated Solid Alternative Fuel), wood waste (sawdust) forms a matrix, to which slug and greasy waste materials are applied. Fuel PAS-r (Shredded Solid Alternative Fuel) is formed from combustible industrial and municipal waste which include wood waste groups. Fuel PAS-r is produced in the BMH installation. The presented tables include physical and chemical properties of PAS-r and PAS-i (fuels from waste) with respect to standards imposed by cement plants. Production of fuels from waste provides opportunities for managing types of wood waste that cannot be used otherwise. [ABSTRACT FROM AUTHOR]

This paper presents the melting characteristics of ash from different residual forest biomass - wood pellets, oak chips, coniferous bark, deciduous tree bark, wet sawdust and non-sorted blueberries. The melting temperatures of ash in reducing and oxidizing atmospheres were similar and did not differ by more than 10°C to 30°C. These values were within a range of 1230°C to 1330°C, and for the blueberry it was more than 1500°C. Only ash pellets melted in a reducing atmosphere at a temperature of 1280°C, and in an oxidizing temperature at 1430°C. To compare, determination tests were also performed for ash from "agro" biomass waste. Ash melting temperatures for biomass composites of agricultural origin (made in an oxidizing atmosphere), turned out to be lower than the temperatures of ash from wood biomass. In the results of the presented elemental analysis, the share of chlorine and sulphur and the impact S/Cl on high temperature corrosion processes were indicated. On the basis of the results for all the tested types of biomass, the calculated ratio S/Cl was below the value of 2.0. This means that the tested biofuels do not meet the safe use of biofuels detailed in the energy sector criterium (from the point of view of boiler operation). [ABSTRACT FROM AUTHOR]

In order to reveal the kinetic mechanism of thermal decomposition of hybrid poplar sawdust as biomass to produce biofuel, the thermogravimetric experiments were carried out at four different heating rates, 5, 10, 15 and 20 °C min −1 using a thermogravimetric analyzer under air atmosphere. The kinetic analysis was performed according to the Ozawa-Flynn-Wall method. The results showed that the activation energy altered from 38.08 kJ/mol to 141.47 kJ/mol. The pre-exponential factor values showed empirical first order reaction. The Gibbs free energy values changed from 102.76 kJ/mol to 184.82 kJ/mol, and the entropy changes were negative, showing that the disorder degree of products obtained by degradation was lower than that of initial compounds. The calorific value of the biomass was 19539 kJ/kg. [ABSTRACT FROM AUTHOR]

Biomass producer gas presents a very promising alternative fuel to diesel since it is a renewable and clean burning fuel having similar properties to those of diesel. In this outline, a multi-cylinder diesel engine is experimentally optimized for maximum diesel savings, lower emissions, and without any excessive vibration of the engine using sawdust biomass as producer gas. Emission parameters of the double-fuel engine at diverse gas flow rates are contrasted with those of diesel at distinctive load conditions. The study brings out that the greatest diesel reserve happens to be 80% at 8 kW load without any engine issue in dual-fuel mode. Carbon monoxide (CO), hydrocarbon (HC), and carbon dioxide (CO2) emissions in dual-fuel mode are more contrasted with diesel at all test extents. Smoke opacity and oxide of nitrogen (NO) emission values in dual-fuel mode are less contrasted with diesel. [ABSTRACT FROM PUBLISHER]

This paper reports about the release qualities of preheated jatropha oil mixes alongside producer gas from waste wood pieces of babul in double-fuel direct injection diesel motor. Jatropha oils were inspected in both individual and double-fuel modes at a consistent gas stream rate of 21.69 kg/h at all loading conditions. From the results it might be inferred that oxides of nitrogen and smoke emission decrease although carbon dioxide (CO2), carbon monoxide (CO), and hydrocarbon (HC) increase for all test fuels in double-fuel operation contrasted with that of a single mode at diverse loading conditions. All fuel blends show preferable emissions over that of diesel. [ABSTRACT FROM PUBLISHER]

The paper presents an analysis of the fuel and emission properties of selected types of post-consumer wood. The tested materials include flooring, wood door frames, and used furniture, as well as wood as a material for comparison. In addition, through the results of tests carried out in the laboratory, the paper presents possibilities related to the optimization of waste combustion plants equipped with combustion chambers with mobile grates. For this purpose, indicators of quantitative assessment were determined, i.e. the reaction rate, the fire point, mass loss during combustion, and the heat load of the grate. [ABSTRACT FROM AUTHOR]

This article aims to determine experimentally the energy potential of samples from oversize compost fraction formed into briquettes. Theoretical combustion characteristics of the briquettes are determined and are compared with a reference fuel. Elemental analysis and stoichiometric calculations were performed for the samples. Classical grate combustion device with manual fuel supply was chosen for combustion tests. Flue gas temperature and emission parameters, such as the emission levels of carbon monoxide, carbon dioxide and nitrogen oxides, were monitored by a multi-purpose flue gas analyzer Madur GA-60. Dependence of these parameters on air input was followed. Elemental analyses and stoichiometric calculations of individual samples indicate favourable properties of the energy compost for further energy utilisation, namely the gross calorific value of 16.42 MJ kg-1. Excess air was causing high losses through heat of the flue gas during the experiments on combustion device. This fact occurred in a situation when the temperature of flue gas leaving the chimney reached high levels. The excess air coefficient also significantly influenced emissions of carbon dioxide and monoxide and nitrogen oxides in the flue gas. The trends are analysed statistically and are expressed by regression equations. The results can serve in practice for optimization of combustion processes in grate boilers with manual feed of the fuel. [ABSTRACT FROM AUTHOR]

The incineration of treated waste wood generates more contaminated fly ashes than when forestry or agricultural waste is used as fuel. The characteristics of these biomass fly ashes depend on the type of waste wood and incineration process parameters, and their reuse is restricted by their physical, chemical and environmental properties. In this study, four different fly ash types produced by two different incineration plants were analysed and compared to Dutch and European standards on building materials. A combined treatment was designed for lowering the leaching of contaminants and the effect of each treatment step was quantified. A pilot test was performed in order to scale up the treatment. It was found that chlorides (which are the main contaminant in all studied cases) are partly related to the amount of unburnt carbon and can be successfully removed. Other contaminants (such as sulphates and chromium) could be lowered to non-hazardous levels. Other properties (such as particle size, LOI, oxide and mineralogical compositions) are also quantified before and after treatment. [ABSTRACT FROM AUTHOR]

The increased demand for waste wood (WW) as fuel in Swedish co-combustion facilities during the last years has increased the import of this material. Each country has different laws governing the use of chemicals and therefore the composition of the fuel will likely change when combining WW from different origins. To cope with this, enhanced knowledge is needed on WW composition and the performance of pre-treatment techniques for reduction of its contaminants. In this study, the chemical and physical characteristics of 500 WW samples collected at a co-combustion facility in Sweden between 2004 and 2013 were investigated to determine the variation of contaminant content over time. Multivariate data analysis was used for the interpretation of the data. The concentrations of all the studied contaminants varied widely between sampling occasions, demonstrating the highly variable composition of WW fuels. The efficiency of sieving as a pre-treatment measure to reduce the levels of contaminants was not sufficient, revealing that sieving should be used in combination with other pre-treatment methods. The results from this case study provide knowledge on waste wood composition that may benefit its management. This knowledge can be applied for selection of the most suitable pre-treatments to obtain high quality sustainable WW fuels. [ABSTRACT FROM AUTHOR]

A low temperature method was used to produce bio-oil from fir sawdust by means of microwave pyrolysis. Effects of reaction temperature, ratios of the microwave absorption medium to sawdust, and reaction time on the yield of bio-oil were investigated. The results show that an optimized yield of 21.22% is achieved. Bio-oil obtained was analyzed by gas chromatography-mass spectrometry and Fourier transform infrared, and the result reveals that the product mainly consists of phenolic compounds with esteric compounds as the minor components. Thermal weight loss curves of bio-oil were determined by thermogravimetry-differential thermal analysis in the oxygen atmosphere at different super-heating rates, and combustion kinetic parameters were calculated. [ABSTRACT FROM PUBLISHER]

The industrial wood briquette making process is an alternative to add value to forestry waste and involves the compaction of sawdust at high pressure and temperature. The present study was performed in an industry in the state of Goiás, Brazil. All kinds of energy involved in the wood briquette manufacturing process were qualified and quantified, in all stages of the process. The methodology used was based on Cotrim (1992), Silva (2001), (BEN, 2007), Inconprera (2008) and NBR 8633. The total energy demand to produce one ton of Pinus wood briquettes using sawdust at 43.8% moisture was 435 kWh. When producing the same amount of briquettes at 11% humidity, this value fell to 101.66 kWh per ton. Thus, drying process of sawdust consumes 76.63% of all the energy used for manufacturing. The amount of energy required for the production of 1 ton of briquettes corresponds to 10.8% (wet sawdust) and 4.37% (dry sawdust) of the energy contained in this one ton of briquettes. [ABSTRACT FROM AUTHOR]

In the present study, sawdust bio-oil (SBO) manufactured by fast pyrolysis of Japanese red pine (Pinus densiflora Siebold and Zucc.) sawdust was analyzed for its volatile chemical compound composition and evaluated for its free radical scavenging potential, inhibition of lipid peroxidation and reducing power. Gas chromatography and mass spectroscopy revealed 29 volatile compounds, comprising 97.6% of the total volatile compounds in SBO. The antioxidant potential of SBO in terms of IC50 values was 48.44 μg/mL for hydroxyl radical scavenging, 89.52 μg/mL for 1,1-diphenyl-2-picrylhydraxyl radical scavenging, 94.23 μg/mL for 2,2'-azino-bis[3-ethylbenzothiazoline-6-sulphonic acid] radical scavenging, and 136.06 μg/mL for superoxide radical scavenging activity. The total phenol content in SBO was 5.7% gallic acid equivalent. Based on the composition of its volatile compounds, high free radical scavenging potential and antioxidant properties, SBO could be used as a source of antioxidant compounds, flavoring agents and nutraceuticals in the food, pharmaceutical, and cosmetic industries. [ABSTRACT FROM AUTHOR]

Background: Reducing the cost of producing cellulosic ethanol is essential for the industrialization of biorefinery. Several processes are currently under investigation, but few of these techniques are entirely satisfactory in terms of competitive cost or environmental impact. In this study, a new ethanol and lactic acid (LA) coproduction is proposed. The technique involved addition of waste alkaline peroxide pretreated hydrolysate (mainly LA and hemicelluloses) to the reaction mixture after ethanol fermentation (mainly LA and xylose) to reduce the ethanol production cost. Results: The following processes were investigated to optimize LA production: no addition of hemicelluloses or hydrolysate, addition of recycled hemicelluloses, and addition of concentrated hydrolysate. The addition of concentrated hydrolysate at 48 hours, which resulted in a maximum LA concentration of 22.3 g/L, was the most environment-friendly and cost-effective process. After the improved fermentation, 361 mg LA and 132 mg ethanol were produced from 1 g of raw poplar wood. That is, the production of one gallon of ethanol produced $9 worth of LA. Conclusions: The amount of LA produced from the pretreated hydrolysate and reaction mixture after ethanol fermentation cannot be underestimated. The recovery of hydrolysate rich in LA and hemicelluloses (or xylose) significantly improved LA yield and further reduced the ethanol production cost. [ABSTRACT FROM AUTHOR]

Based on the particularities issued by the increasing carbon dioxide concentration in the atmosphere and the climate changes that we have already experienced, the redeemable power sources gain more and more ground (solar power, wind power, biomass, geothermal power, sea wave's power). The local factor is represented by the existence of huge quantities of beech wood wastes resulted from the wood primary processing. These wastes could be used as biofuel by consensus with the durable development requests, as the wood accumulates solar energy, grows in our atmosphere taking carbon dioxide from air, minerals from soil, energy from the Sun and eliminates oxygen, and when it is burned off, the carbon dioxide is eliminated back in the atmosphere. On the other hand, the caloric value of the wood is comparable to the other fuels currently used to warm our houses. The conclusion of the experiments shows that the optimum solution for the presented issues depends mostly on the technologies and plant/equipment being used. The more and more performing and variable technologies, the particular requests of the wood processing industry and financially stimulating politics make bases of the efficiency for using completely these redeemable power sources. [ABSTRACT FROM AUTHOR]

In energy valorization by burning solid biomass fuels, the achieved thermal power is relatively low, so that maximum electrical power is about 2 MW for agricultural waste and 5 MW for wood waste. Low power turbine construction involves solving a multitude of functional and structural problems. This paper examines different solutions for steam turbines up to 2 MW electrical power. The thermo-economic analysis is carried out for a 200 kW steam turbine used for valorizing energy willow, resulting from its harvesting experience in Romania. [ABSTRACT FROM AUTHOR]

The first objective of this paper was to provide an inventory of developments of certification schemes for sustainable biomass production, following recent EU legislation (both formalized and under development). One main pillar is the EU Timber Regulation for legal harvesting; a second one is the EU’s 2010 recommendations for sustainable woody biomass sourcing for energy; the third one is the EU Waste Directive. The second objective was to benchmark the coverage of this (draft) legislation, when wood product certificates for sustainable forest management (SFM) are used as proof of the related legislative requirements. We studied North America, as it is a major biomass supplier to the EU-28. Together with existing forest legislation in the US and Canada, SFM certificates are actively used to cover the EU’s (draft) legislation. However, North American forests are only partially certified with fibers coming from certified forests; these are referred to as forest management (FM) fibers. Other certified fibers should come from complementary risk assessments downstream in the supply chain (risk based fibers). Our benchmark concludes that: (a) FM fiber certification by the Forest Stewardship Council (FSC) and the Program for the Endorsement of Forest Certification (PEFC) international standards show the highest level of coverage with EU’s (draft) legislation; (b) There is insufficient coverage for risk based fibers by FSC Controlled Wood (FSC-CW), PEFC Due Diligence (PEFC-DD), or SFI-fiber sourcing (SFI-FS). Other weaknesses identified for elaboration are: (c) Alignment in definitions are needed, such as for primary forest, high carbon stock, and wood waste (cascading); (d) Imperfect mass balance (fiber check downstream) needs to be solved, as non-certified fiber flows are inadequately monitored; (e) Add-on of a GHG calculation tool is needed, as GHG life cycle reporting is not covered by any of the SFM frameworks. [ABSTRACT FROM AUTHOR]

This work is focused on the use of biomass waste to feed already existing coal combustion plants as a part of paving the way toward the reduction of the environmental impact. The biomass waste supply chain optimization is critical to conceive long-term viable projects and deal with the biomass heterogeneous nature and drawbacks to be used with coal, i.e. principally high moisture content and low bulk density. This paper studies biomass transportation, storage and change of properties (moisture content and hence dry matter, energy density and bulk density) through the use of different pre-treatments: (i) torrefaction, (ii) torrefaction combined with pelletization, (iii) pelletization, (iv) fast pyrolysis and (v) fast pyrolysis combined with char grinding, which produce a range of very different pretreated biomass. The optimization problem is formulated as a mixed integer linear program (MILP) that evaluates the net present value and the environmental impact through a life cycle assessment (LCA). The results propose location-allocation decision together with the selection/capacity of pre-treatment technologies for each scenario. The scenarios contemplate different biomass characteristics, availability and distribution for a supply chain case study located in Spain: forest and agricultural woody residues used to replace at least 10% of the total thermal inlet power provided by coal in the existing network of thermal plants. [ABSTRACT FROM AUTHOR]