In the making process of carbonized fuel from biomass, it is important to understand the temperature dependence of product yields and to examine heating value and grindability of carbonized fuel. In this study, the carbonization experiments of Japanese pine pellets are conducted to define the carbonization characteristics of woody biomass and properties of its char in the basic apparatus. Yields of carbonization products in experiments show that the char yield decreases and the volatile yield increases when carbonization temperature goes up. It was found that yields of carbonization products change significantly between 300 and 350 degrees Celsius. From the results of analysis of char, the influence of carbonization temperature for the heating value, fuel ratio and grindabiligy were defined. The chemical structure of char was analyzed by FT-IR.

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Carbonization of woody biomass generally leads to a char yield only of 20?30% and large part of intrinsic chemical energy of the feed biomass is lost as volatile matters such as tar. The present study carried out experiments on tar recovery during carbonization of the feed biomass with the char that was produced in advance. The resultant char adsorbing the tar in it can be utilized as fuel. The carbonization temperature was 400, 500 and 600℃ and the temperature range of the char particle layer for tar recovery was set around 200?400℃. The char yield decreased with increasing the carbonization temperature, but total yield of the char and recovered tar was the maximum, 51% at 500℃. The total energy yield of the char and recovered tar was more than 70% at 500 and 600℃, while the energy yield of char alone was less than 35%.

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Liquid fraction produced during carbonization of iron-loaded wood at 800℃ was modified by making it pass through the fixed bed of ultra fine nickel and iron particles dispersed in 500℃-char of wood. Although the resulting oil portion was moderately cracked and deoxygenated, its heating value was lower than that of biodiesel fuel. It is thus proposed that the modified oil should be blended with bio-ethanol to use as an automotive fuel.

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This paper describes the results of gasification test used Carbonized Sewage Sludge. It reveals that the sufficient calorific value of syngas for gas engine had been obtained by mixing Carbonized Sewage Sludge and woody biomass. This way has control the fluctuation of Carbonized Sewage Sludge properties and the fuel cost would be cheaper than woody biomass. It would be effective to increase energy use of the sewage sludge and woody biomass.

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Comparison of gasification behavior of pulverized biomass charcoal with pulverized coal in blast furnace is necessary to use biomass charcoal in substitution for coal. The gasification behavior of these materials were observed by use of raceway hot model which simulated the lower part of blast furnace. The experimental results showed that the gasification behavior of biomass charcoal was affected by the quantity of the volatile matter as well as coal. And because the biomass charcoal had less quantity of ash than coal, the pressure drop of raceway in furnace decreased.

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Heat transfer and heterogeneous chemical reactions in a biomass particle during pyrolysis were investigated numerically. When the lignin decomposition would occur mainly, the temperature in the particle increased with the effect of the radiation heat transfer through the pores. If the tar decomposed to char and gas, the temperature in the particle increased slightly due to the exothermic reaction of char formation and the yield of gas was more than those of tar and solid. Time course of the temperature at the center didn't depend on the lignin content of the biomass. However, the higher the lignin content of biomass made the more the yields of the tar and solid and the less the yield of gas at steady state for 673K < T_S (setting temperature) < 1073K. There were two regimes for the relationship between the setting temperature (T_S) and the maximum gas flow rate didn't depend on the lignin content. The gas could be formed by the decomposition of cellulose and hemicellulose for T_S < 573 K while it would be formed by the decomposition of lignin for TS > 573 K. The maximum gas generation rate depended on the volume of the particle until a certain particle size, Dp*(a few mm). On the other hand, it depended on the surface area of the particle for Dp > Dp*.

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Hybrid catalysts composed of a specially designed methanol synthesis catalyst and solid acids could make butane-rich paraffin mixture from synthesis gas containing CO_2, at below 300℃ and under 2-3 MPa. The catalyst could make similar hydrocarbon mixture from only CO_2 and H_2. The product contained little dry gas (C_1-C_2) and C_6+ paraffins. The catalyst could be used more than 5,000 hr without regeneration and the deactivated catalyst was regenerated in situ. The combination of this process with the well designed gasification process gave the energy recovery of about 40% or higher, from woody biomass.

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In order to produce feedstock gas for BTL fuel synthesis process, pressurized gasification is an option. Pressurized fixed bed gasifier was chosen and an experimental setup was made for biomass gasification. Whole apparatus including gasifier, material hopper, feeder, etc. were put inside a pressure vessel. As a result, the difference between the two raw materials, PKS (Palme kernel Shell) and wood pellet, was seen in adaptability to the fixed bed gasifier. Gasification reaction was achieved well in the experiment for PKS while the trouble such as the channeling of the gas flow was caused using the wood pellet. Such trouble was reduced by lowering the bed height of the materials inside the gasifier, and outlet gas temperature increased by bed height lowering.

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This work studied a three reactors circulating fluidized bed biomass and coal co-gasification process. The three reactors circulating fluidized bed is constructed by a tar reforming reactor, a gasifier and a combustor. The circulating material is CaO made from limestone. The CaO works like heat transfer material, tar reforming catalyst, CO_2 sorbent, and sulfur sorbent.

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Power generation of combustion of the oil of the gasification technology which uses the diesel engine by the oil of Jatropha and the Jatropha seed oil expression residual substance, and Jatropha, and the dual-fuel combustion technology of Jatropha oil and biogas were developed. Carried out operate examination for long time by this generation technology, report it.

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The purpose of this study is to assess the energy and environmental performance of a mechanochemical method for preparing cellulose nanofibers (CNF) from woody biomass using a life cycle assessment approach. The energy requirements and greenhouse gas (GHG) emissions from CNF production were compared to those of petrochemical polypropylene (PP) production. The functional unit used in this study was 1 kg dry CNF. The background data (emission factor of industrial steam and water, wood density, and grid emission factor etc.) were collected from the Inventory Database for Environmental Analysis (IDEA) and published literature. The foreground data (power, heat, and water requirements in CNF production plant) were obtained from pilot plant experiments. The energy requirements for preparing CNF were 11.1〜30.2 MJ/kg, which were lower than that of PP (63.4 MJ/kg). The GHG emissions of preparing CNF ranged from 1.2〜3.7 kg CO_2 eq./kg, without accounting for carbon fixation of biomass. Water consumption for producing CNF was 17.8〜19.4 L/kg, which was much lower than that of PP (258.6 L/kg). When the CNF were used to produce composite with PP, the maximum GHG reduction was 2.4 kg CO_2 eq./kg, taking into account carbon fixation of biomass. The results showed that the utilization of CNF prepared from woody biomass using the mechanochemical method could contribute to saving energy and mitigating GHG emissions.

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The aim of this study is the assessment of energy consumption and CO2 emissions in the manufacture of wood tray. The energy consumption and CO2 emission were clarified in the manufacturing process composed of transport, sawmilling, boiling, slicing, and pressing. The energy consumption and CO2 emission per 1 kg wood tray of initial type system were 1.65MJ/kg and 0.11kg-CO2/kg for transport, 8.86MJ/kg and 0.56kg-CO2/kg for sawmilling, 26.68MJ/kg and 1.70kg-CO2/kg for boiling, 4.17MJ/kg and 0.27kg-CO2/kg for slicing, 82.62MJ/kg and 5.26kg-CO2/kg for pressing, and 123.98MJ/kg and 7.91kg-CO2/kg for total. In improved system, the energy consumption and CO2 emission were 1.23MJ/kg and 0.08kg-CO2/kg for transport, 2.43MJ/kg and 0.15kg-CO2/kg for sawmilling, 0.18MJ/kg and 0.01kg-CO2/kg for boiling, 0.58MJ/kg and 0.04kg-CO2/kg for slicing, 27.46MJ/kg and 1.75kg-CO2/kg for pressing, and 31.88MJ/kg and 2.04kg-CO2/kg for total.

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The CO_2 emission in energy conversion sector, mainly, the emissions in industrial and transportation sectors are comparatively large in Japan. One of countermeasure for reducing CO_2 emissions in these sectors would be promotion of BTL fuel. The recycled CO_2 gas which would be generated by CCS process, for instance, may be feedstock of methanol production system. Based on the current R&D level, we propose the MeOH production system due to Bio-H2 sand recycled CO_2 gas of fossil fuel origin, and the low pressurized MeOH synthesis production system. In order to compare their environmental impacts, we analysed the benefit of CO_2 emission reduction on LCA basis. As a result, it implies that the MeOH production system due to recycled CO_2 gas is advantage in comparison to conventional system of fossil fuel origin. Also, on the low pressurized system, the same effect would be obtained, too.

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The purpose of this study is to design a biomass utilization system for different types of biomass resources, fuel production technologies, and energy conversion technologies. Evaluation of biomass utilization system has been studied considering single resource or technology. However, the evaluation methodology for different resources and technologies is not established yet. In this study, the biomass energy system has been modeled and integrated for several types of biomass resources and technologies. The system consists of 4 processes; Resource, Fuel Production, Energy Conversion, and Waste treatment. By using this model, energy balance, CO_2 emission, economic impact of the biomass energy system can be evaluated.

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A purpose of this study is to evaluate the CO_2 emissions from the land use change for calculating lifecycle CO_2 (LC-CO_2) emission of Jatropha oil based biofuel. A Japanese law for expanding non-fossil fuel set in 2010 indicates that the publication of IPCC or global authorized, fair and neutral data should be used for the calculation. Therefore, based on the IPCC publication and supplemental documents, we extracted challenges on evaluating carbon stock quantity by calculating stock difference before and after cultivation in above-ground, below-ground and soils. As a result, it became clear that, in the grassland, the emission of the CO_2 was lower than 50% of fossil fuels, or emission standards on the law. However, in the shrub, it was more than 50%. There were very few areas of less than 50% in Indonesian Kalimantan Island.

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Supercritical water gasification technology (SCWG) is a technology to efficiently convert wet biomass to energy. Activated carbon is used as a gasification catalyst in supercritical water gasification. Therefore, we confirmed the effect of activated carbon concentration in supercritical water gasification of shouchu residue. As a result, there is a relation between activated carbon concentration and the plugging at heat exchanger tube by tar.

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Glucose decomposition in supercritical water shows interesting characteristics such that slow heating rate results in higher yield of char while fast heating rate results in higher carbon gasification efficiency. The effect of pressure is mainly observed in the supercritical temperature and not in the subcritical temperature. Acid addition results in both gas and tarry material yields enhancement. By applying reaction network model, and determining the reaction rate parameters for each reaction in the network, distinction between radical and ionic reactions were made, and these phenomena could be explained.

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In this study, hydrothermal treatment of coconut shell (200℃, 30 min), and separation of the reaction products using a filtration and an activated charcoal chromatography method were conducted. Water soluble reaction products were mainly xylose, acetic acid and furfural. Xylose and acetic acid were recovered with high yield by the filtration without water washing process. However, in case of furfural, it was necessary to wash filter cake with water. Furthermore, furfural could be separated by the activated charcoal chromatography.

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The N,N'-diacetylchitobiose (GlcNAc)2 yield after enzymatic degradation of chitin following pretreatment with high-temperature and high-pressure water (400℃, 1 min) and grinding (10 min) was 93%, compared with 5% without any treatment, 37% with high-temperature and high-pressure water pretreatment alone (400℃, 1 min), and 60% with grinding alone (30 min).

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In this work, we aimed to explore operating conditions where polysaccharides (β-glucans) in various biomass resources can be depolymerized to form bioactive low-molecular-weight saccharides by using several hydrothermal treatment techniques. As the results, we found that dried wakame particles were converted to desired products with molecular weights of 5 - 30 kDa from the initial molecular weight (more than 200 kDa). In case of kikurage, we found that hydrolysis of β-glucan in kikurage took place in an efficient manner and desired low-molecular-weight fraction with 5-15 kDa at 180℃ for more than 1 h. Hydrothermal electrolysis of the hydrolysates obtained by hydrothermal electrolysis of bamboo particles was able to generate some kinds of value-added chemical intermediates (e.g. dicarboxylic acids) via partial oxidation of saccharides on this treatment at 120-160℃ and direct currents of 1-5 A for 0.5-3 h.

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Short rotation willow coppice is one of the most promising energy biomass crops. In this research, we studied mechanical, chemical and preserving potential of the short rotation willows. 4 willow clones were collected at 1 and 2 year of cultivation. Particleboards were fabricated from willow chips, and measured their mechanical properties. Willow clones showed enough bending properties for practical use, and 0.7 g/cm^3 density board satisfied 18-type of JIS A 5908. About chemical composition, wood part of 2 year willows had higher holocellulose ratio compared with 1 year willows. Willow barks had higher insoluble lignin, ash, and extract content compared with willow woods. Among willow clones, SEN clone showed especially high extract content.

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In the food industry, the syrup containing a high concentration of sugar used for fruits storage is abundantly discharged as a food processing waste, and almost disposed by incineration. It results in the rise of the manufacturing cost and environmental pollution. This study demonstrates that waste syrup is utilized as carbon source for production of docosahexaenoic acid (DHA) and astaxanthin (Asx) by thraustochytrid, Aurantiochytrium sp. strain KH105. KH105 could be grown in the culture medium containing 3-50% waste syrup, and the maximum yields of DHA and Asx were obtained at 207.6 mg/L and 1.1 mg/L. When the culture medium condition was optimized, DHA and Asx yields increased 2.1 and 1.5 times, respectively, as much as in the standard culture condition. When the waste syrup treated with activated carbon was used, Asx yield increased 2.3 times with reduction of the citrate concentration in waste syrup. This study shows that the functional lipid production by thraustochytrid is effective as the utilization of waste syrup.

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Jatropha curcas has high potential as an energy crop. Jatropha seeds can be pressed into bio-oil that has good characteristics for direct combustion in compressed ignition engines or for the production of biodiesel. However, more than 60% weight of raw material remains as residue after screw-pressed, therefore utilization technology of Jatropha residues is required. In this study, biogas production from seeds of Jatropha after screw-pressed was examined according to components of seed residues. Cumulated biogas production from unseparated, episperm and endosperm part of seed residues was 452, 216 and 798 mL g^<-1> VS, respectively. High biogas production from endosperm is probably due to high contents of easily decomposable organic matter like fatty oil. In contrast, low biogas production from episperm is probably due to high contents of persistent organic matter like lignin. Consequently, biogas production per organic input from seed residues of Jatropha was more than that from cow manure, therefore it can be concluded that single fermentation of seed residues of Jatropha after screw-pressed is feasible under this experimental condition.

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EBARA Environmental Plant (EEP) has constructed several biomass energy plants with a swirling flow type fluidized-bed furnace. Domestically, internally circulating fluidized bed boiler (ICFB) is the major model for power plant fueled by scrap lumber, wood chips, and paper sludge waste. Meanwhile in overseas, relatively large-scale power plants of fluidized-bed incinerator (TIF, European name is "TWINREC-TIF"), have been constructed as Waste to Energy Plant for multi fuel (municipal solid waste and sewage sludge) by licensed company. In this paper, representative example of actual plant and future prospects of our business are presented.

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We conducted a pilot test of a small-scale methane fermentation system using heat from a hot spring, and evaluated its environmental impact. In the pilot test, although both the concentration and quantity of methane gas were influenced by temperature, they increased with increasing microbial growth. Therefore, a system responsive to temperature change could be designed by increasing the diversity of acclimatized microbes. When income and output for 1 year were taken into consideration, the impact of this system was equivalent to or smaller than that of a standard methane fermentation system. Therefore, in this area, it would be both environmentally and economically advantageous to install systems in several places, rather than a standard methane fermentation system in one place.

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Based on the proposal of the forum on the Northeastern Japan Revival in the7th Biomass Science Meeting last January 2012, we have been discussing with people and local governments of Iwate, Miyagi, and Fukushima Prefectures for supporting the revival activities from the disaster 3.11 2011 in Northeastern Japan by utilizing biomass energy. Especially, efficient utilization system of non-utilized biomass resources including wastes caused by the disaster should be established in terms of their collection, storage and transportation in the local areas, in order to design the energy supply center of cogeneration of heat and power for public facilities such as schools and hospitals. In addition, combined utilization system of biomass with other renewable energies is to be developed through the intimate communication and exchanging information with local people and governments related to such biomass utilization schemes.

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Since the accident of nuclear reactor at Fukushima, it becomes important problem to evaluate the influence of radioactive isotopes. Therefore, the comparison and evaluate of radioactivity concerning forest woody biomass and the food were performed. The problem of higher radioactive ash after combustion of woody biomass was examined and also the relation between radioactive cesium and potassium40 are investigated. Finally, the biomass of low radioactivity is discussed.

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Phytoremediation is an emerging technology, which uses plants to remove pollutants from contaminated sites. In this study, bioethanol production and cadmium removal from phytoremediation plant was investigated. We used the rice straw (Oryza sativa L.) for the remove of cadmium from contaminated sites. Oryza sativa L. was contained 80 ppm of cadmium after phytoremediation treatment. When Oryza sativa L. was treated by 2% of sulfuric acid and enzymes, 75% of sugar yield and 90% of cadmium release were achieved. Furthermore, production of bioethanol from rice straw by simultaneous saccharification and fermentation (SSF) using Schizosaccharomyces japonicus was investigated. 16 (g/L) of bioethanol was produced.

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In March 2011, Great Earthquake was occurred in east Japan, and led to the catastrophe caused by the tsunami in Sanriku coast. In the town of Minamisanriku, located in the northern part of Miyagi Prefecture, 612 people were dead, 226 people are missing, 3,316 houses were stricken partially or completely destroyed. The amount of rubble generated in this disaster is 817,000 tons estimated in this area. We built a gasification generation plant to handle this earthquake rubble, and have carried out its operation. In this paper, we report the overview of this gasification plant and the actual process.

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In order to decontaminate of radioactive substances in agricultural lands and forests, we are developing the densification technologies for the polluted bulky biomass. In the primal study, comminution and pelletization in the small scale were carried out for woody branches and leaves obtained from forest in FFPRI (Ibaraki and Tokyo). As a result, densification ratios were from 1/3 to 1/8 by comminution and from 1/6 to 1/25 by pelletization. By mixing wood part with leaves and branches, the mixed pellet showed enough durability. Densification test for herbaceous and woody biomass in a larger scale (200kg/h of feedstock) is in progress at Yamakiya district in Kawamata-town. Fukushima Prefecture, in order to design the commercial plant.

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The aim of this study is to investigate the effects of artificially controlled environment, especially elevated pressure, on the photosynthesis and respiration during plants growth. The pressure affects not only cells and organelles in leaves directly but also diffusion coefficients and degrees of solubility of carbon dioxide and oxygen. In this study, photosynthesis of a model plant, Arabidopsis thaliana, was investigated under elevated pressure in a chamber made of acrylic and aluminium. Fluorescent lamps were set up around the chamber as the light sources. The photon flux density (PFD) for the plant was able to be changed from 0 to 70 μmol/m^2s. The pressure and absolute humidity were varied from 0.1 to 0.5 MPa and from 0.78 ×10^<-2> to 13 ×10^<-2> kg/kg', respectively. The effects of elevated pressure on the photosynthesis were analyzed by measuring a change in the amount of carbon dioxide in the chamber. The results clearly showed that the amount of photosynthesis increases up to 1.5 times with increasing pressure. The results indicate that the photosynthesis during plant growth is improved under elevated pressure. There are possibilities that the obtained results are applicable to cultivate biomass more efficiently in plant factories in the future.

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From the viewpoint of energy security, development of new energy production systems is needed to prevent exhaustion of fossil fuel. Biomass is expected to be one of the most remarkable alternative sources of energy, because biomass is the product of plant photosynthesis converting carbon dioxide to organic compounds. So far, to use the biomass effectively, it is needed to select appropriate plants which contain a lot of fuel components (e.g. starch, oil, terpenes) and investigate its combustion characteristics. Moreover, development of methods for using biomass effectively is important. The aim of this study is to investigate the effects of artificially controlled environment, especially elevated pressure, on the plant-growing speed. In this study, we designed and constructed a plant-growing chamber to control the environmental parameters. Fluorescent lamps were set up around the chamber as the light sources. By using the chamber, the photon flux density (PFD) for the plant was able to be changed from 0 to 70 μmol/m^2s. The pressure and absolute humidity were varied from 0.1 to 0.5 MPa and from 0.78 ×10^<-2> to 13 ×10^<-2> kg/kg', respectively. An aquatic plant, Spirodela polyrrhiza, was used as a test plant to evaluate its growth rate under the elevated-atmospheric pressure varying from 0.1 to 0.4 MPa. The results clearly showed that the growing rate increases up to 1.22 times under 0.2 MPa. It was suggested that photosynthesis was improved under the conditions of elevated pressure.

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How to get a new wood chip ,as a pellet-substitute? Chip-fuel has a difficulty on the feed flow, at the fuel-silo. As an indicator of the particles-sliding on sloped surface, the repose angle of the various particles should be adopted. considering the inter-particle friction.

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We extract the problems in the dissemination of biomass energy in Japan. Here is a report about the results of the study on issues such as energy policy, legislation, professional development, the use of Japanese materials, system FIT, in the country. I recommend, to develop plan to deal with the heat FIT, to train like professionals, such as forester of Germany etc.

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This work clarified an improvement to the enzymatic saccharification and volume reduction of rice straw pellets. During pelletization, rice straw is triturated under high temperatures and pressures. This increases the saccharification rate to 36%, over 20% higher than crushing alone. The bulk density of the pellet is 0.64, over four times as much as that of a rice straw roll bale. The collection and transportation cost of pelletization system was slightly higher than that of the conventional system. The cost of the secondary transport and loading-unloading was cut by the volume reduction. However, this did not lead to a reduction in overall cost because of the higher cost of pelletization.

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Cotton which is mainly composed of cellulose accounts for about 60 percent of the fiber waste. When the hydrolysis of cotton and the fermentation are performed, the lactic acid which is a raw material of poly-lactic acid is generated. However, general hydrolysis has problems that the 5-hydroxymethyl furfural (HMF) which is generated on hydrolysis disturbed the fermentation and the addition of the catalyst separation process is necessary. Then, the lactic acid is selected as a catalyst to reduce the catalyst separation process because lactic acid is a product on fermentation. Therefore, whether batch type reactor or fixed bed flow reactor is suitable to reduce the HMF on hydrolysis was examined. As a result, it turned out that fixed bed flow reactor is suitable because glucose was flowed out properly to control the production of HMF. Besides yield of glucose is sure to rise if effect of retention time was elucidated.

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Utilization of energy crop is the major option for stable bioenergy production at low cost and that will not compete with food production. Further energy crop must be grown in marginal land. The objective of this study is establishing the scenario for bioenergy feedstock production using wild Miscanthus species in cold and snowfall area (CSA) where is not suitable for biomass production (BP) due to short and stressful growing season. 43 wild accessions of M. sinensis from different areas were grown side-by-side at an experiment field in CSA to identify major factors involved feedstock production. The study was carried out for four growing seasons (2008, 2009, 2010, 2011). From 2008 and 2009 studies, large variability among wild lines was observed and then five high yield performance lines were selected under non fertilization conditions. In the study from 2010 to 2011, selected breeding lines were used to evaluate the effect of field managements to B_P. Finally, a scenario was established integrating environment (temperature, growing degree-days), M. sinensis genotypes (morphological growth duration), field management (weed control, fertilization) and harvesting time. Although the harvesting time remains under consideration, it could be applicable that wild M. sinensis is domesticated as a promising energy crop in cold region with BP between 25〜30 t ha^<-1> without fertilizer input.

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We compared the effects of differences in thinning and transportation methods for sawing logs and logging residue logs on the profitability of forestry operations in Niyodogawa, Japan. As a result, the profit per hour was greater when the machine cost was low and working efficiency was high for thinning and transporting sawing logs, and the profit for transporting logging residue logs was high when carrying capacity was high. It was clear that if lumberyards are established in Niyodogawa, the profitability will be higher due to the shorter transportation distance and lower costs. In future studies, it will be necessary to examine the break-even point, thinning scale and arrangement of lumberyards, and optimize the methods for thinning and transporting logs.

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The effect of metal-modified catalyst on the pyrolysis behaviors of jatropha de-oiled cake was examined. With py-GC/MS method, ca.80 % of aromatic hydrocarbons with other by-products was produced in the presence of Ni/activated carbon or Pt/zeolite catalyst. The aromatic selectivity is dependent on both the weight ratio of catalyst/jatroppha and reaction conditions. In fact, under conditions of quartz reactor and Pd/zeolite catalyst, the aromatic selectivity was found to be ca.40% and efforts have been made to improve selectivity and oil yield.

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Producing the bio-oil with flash pyrolysis of biomass is one of effective usage as a final stage of biomass refinery. 48% of Japanese planted forest is consisted of Japanese cedar and most of the thinned woods are left in the forest stand and not utilized. So it is necessary to use them effectively as resources of bioenergy such as pellets, char and chips. In this study, the most suitable pyrolysis condition to produce bio-oils was investigated using Japanese cedar and Moso bamboo. As the results of GC analysis from cedar pyrolysis under different temperature, total peak area in GC was increased with temperature and,major peaks area were increased to 550℃ and after that these peaks area were decreased to 600℃ except for levoglucosan. Amount of levoglucosan increased as temperature raised up from 400 to 600℃.Comparing with bio-oil compositions produced from heartwood, sapwood, bark and trunk pyrolysis, levoglucosan obtained by the primary thermal degradation of cellulose was detected as a major peak in the composition from bark. From GC profiles from other tissues, pyrolitic products were consisted of thermal degradation products from cellulose hemicellulose and lignin according to components of raw material. The largest total peak area of pyrolysis products in GC analysis was from heartwood.

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Carbohydrates (holocellulose and α-cellulose) prepared from bamboo were pyrolized with pyrolizer with GC. Main products were furfural, 5-hydroxymethylfurfural and levoglucosan. To evaluate the formation mechanism of these compounds, other polysaccharides, dimer and monomer. While levoglucosan was found in the pyrolitic products from cellobiose, pyrolysis of glucose, sucrose, maltose and starch yielded as a minor product. Furfural and 5-hydroxymethylfurfral were produced from mono-, di- and polysaccharide except for starch. Formation of pyrolytic products investigated in this study should be depended on streospecific effect of carbohydrate.

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The reforming of biomass tar during gasification was carried out in a two-stage fixed bed reactor using nickel-loaded brown coal char (20 wt.% of nickel) prepared by an impregnation method. The effect of catalyst pretreatment (400, 500,600 and 650 ?C) and reforming temperatures(400, 500, 600 ?C) on the tar reforming property was investigated.Although tar reforming was promoted by increasing reforming temperature, the performance high enough was obtained at 500 ?C using the catalytic pretreatment at 500 ?C. In addition, transmission electron microscopy reveals that the Ni species are well-dispersed in and outside brown coal char at catalytic pretreatment temperature lower than 600 °C.

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Recently, wood biomass is promoted as the substitute of fossil fuel. Hinoki are one of the famous tree types in Japan. Waste wood is plentiful as a by-product of processing in Japan because wood has such a variety of uses as building,engineering works and boat building. Gasification of hinoki waste wood can generate fuel for engine dynamos. Then, it enables energy use except heat use. In this study indirect gasification is carried out by using a closed gasification reactor. The purpose of the study is to research the influence of water rate, pressure and heating temperature on the volume and composition of the gas generated. In an experiment, the heating temperatures ranged from 600℃ to 900℃ every 100℃. Also water rate (mass of the water/ mass of the dry sample+ mass of the water) ranged from 0% to 50% every 10%. One collection method is to collect the gas generated after stopping pressure rise inside the reactor, and the other is to do so, maintaining the pressure at a certain degree of Pascal inside the reactor. We compared the volume and composition of the two types of gas generated

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