In biomass gasification power generation processes, the reduction and removal of tar generated in gasifiers is essential. In this study, a test for the removal of simulated tar components by a packed layer of sawdust was carried out with the aim of establishing a low-cost packing material tar removal technology. Using phenol as the simulated tar, the removal rate and maximum removal of phenol by sawdust were measured under a wide range of vapor pressure conditions across the dew point. Based on the experimental results obtained, a model for tar adsorption and coagulation removal was investigated.

With the introduction of both semi-trailers and European-type CTLs in Hokkaido, the availability was estimated to be 6,673,221 m³/year and 1,334,644 m³/year for used and unused woody materials, respectively. As for used woody materials, the value was significantly higher than 3,741,000 m³/year of coniferous material production in Hokkaido. The value of unused woody materials also showed a value that almost satisfied the wood chip 1,431,753 m³/year, which was a woody biomass fuel in Hokkaido. The increased availability was estimated to be 144,035 m³/year and 28,807 m³/year for used and unused woody materials. As for used woody materials, the value was converted to 1.49 billion yen/year in terms of monetary value and 3,648 houses/year in terms of single-family homes. For unused woody materials, the value for power generation was converted to 190 million yen/year in terms of monetary value and 3,688 households/year in terms of the number of households. The effects obtained by introducing both semi-trailers and European-type CTLs would not be small, and this implies that the introduction will lead to further use of forest resources.

5-Hydroxy methyl furfural (HMF) is a substitute for petroleum-based building blocks in fine chemicals and plastic products produced from agriculture by-products. Sago pith waste (SPW) is solid biomass residues from sago starch industry activity that consists of starch and fiber. This study developed a mixture model based on SPW consisting of starch and cellulose, aiming for a higher yield of HMF. The mixture became a feeding for HMF production in a simultaneous conversion reaction with catalysts in one pot. The condition of starch and cellulose for gaining HMF is different. However, a higher yield was obtained from the 3:1 (starch: cellulose) mixture at 160°C for 8 minutes, as much as 59.95%. In addition, this study also noted the importance of activated carbon and sodium chloride addition in a one pot system to get a higher HMF yield.

In this study, we clarified the economic required condition for wood chips fuel type small-scale gasification CHP business with wood chip on-site drying system. The IRR was 2.5 % in the base case condition we set. However, it became clear that it is difficult to secure the business feasibility of the five items examined in the sensitivity analysis when the conditions are worse than the base value.

Metal-organic-framework (MOF) is a metal-ligand coordination network, which has been applied for petrochemical separation, gas storage etc. It also shows promising catalytic prospective for woody biomass valorization. Cu-Zr@MOF818 which was developed by Liu et al showed stability in various pH and temperature ranges. ¹⁾ In this study, the CuZr@MOF-818 was successfully modified for catalyst use by microwave heating. The crystal structure was confirmed by X-ray Diffraction (XRD) analysis. And the crystallinity of the Cu-Zr@MOF-818 samples was lowered by reducing the reaction time. Cedar wood powders were degraded by the synthesized Cu-Zr@MOF-818 catalyst under alkali condition with the assistance of microwave heating. Organic acids including lactic acid, glycolic acid and hydroxybutanoic acid were detected from the degradation products. Furthermore, aromatic products including guaiacol, 2-methoxy-4- methylphenol, catechol, vanillin, 4-ethyl-2-methoxyphenoxy, acetovanillone, dihydroconiferyl alcohol, dihydroconiferyl acid were detected as the main lignin-derivative products.

In order to control the moisture content of the chips of Japanese Cedar with higher accuracy, in the process of wood chip gasifier, we investigated the time change of the moisture content due to warm air ventilation. Even if wood chips are manufactured from the same log, it is difficult to experimentally cover all the conditions because the shape and initial moisture content of wood chips are significantly different. Therefore, a drying test was performed by changing the chip size, and the drying speed was analyzed by a thermos-fluidic approach to calculate an approximate formula for obtaining the drying time for each chip size.

Among decentralised small-scale biomass energy sources with potential to revitalise local communities, combined heat and power (CHP) from gasification is promising in terms of its high power-generation efficiency, but it has not yet achieved stable operation, partly due to the variation in the moisture content of the wood chips that are used as fuel. This study reports on the techno-economic evaluation of a system using CHP, a wood chip-fired boiler and an organic Rankine cycle as heat sources, based on the assumption that a centre capable of efficiently producing high-quality dry chips is to be set up in a sawmill.

Willow trees are used to make effective use of dormant forest lands, which are increasing as the population decreases. Willow trees are fast-growing trees and require little reforestation, which reduces the cost of cultivation. We estimated the unit cost of power generation and the unit cost of reducing carbon dioxide emissions when willow trees are used as fuel for power generation.

Semi-flow hydrothermal treatment of beech (Fagus crenata) wood was used to fractionate its cell wall component into cellulose-rich insoluble residue and lignin-rich precipitates, and the evaluation of the enzyme-medicated digestibility of the insoluble residue and the photoluminescence properties of the precipitate were investigated. For the residue, enzymatic saccharification was greatly enhanced by the improvement of enzyme accessibility. In contrast, the precipitates dissolved in DMSO and its solution showed obvious photoluminescence by controlling the chromophore distances. Furthermore, 2-naphthol, a carbocation scavenger that inhibits lignin recondensation, was impregnated into wood flour prior to the hydrothermal treatment. As a result, the digestibility of cellulose component in the residue was improved since the formation of unproductively-binding between lignin and enzyme was suppressed along with the suppression of lignin recondensation. In contrast, the photoluminescence intensity of the precipitates was significantly enhanced, suggesting that 2-naphthol bound to the side-chain of lignin molecule contributed to the photoluminescence properties of the lignin. This information would give us a clue to utilize the whole cell wall component.

The purpose of this study is to develop an electrochemical heat pump using β”-alumina solid electrolyte that operates in the high temperature range of 700K or higher. Based on the measured electrode characteristics, the compression efficiency of the electrochemical compressor was analyzed under various temperature conditions. Performance calculations show that compressor efficiency𝜂_𝑐𝑜𝑚 at T_H =1000K, G=10, B=1000AK^0.5/(m²Pa) is about 65% when the compressor is operated at 100A/m² .

Sink float separator is intended to separate the mixed plastics (PE, PP, PET) as to apply on the difference in specific gravity between the water and each plastic. A vertical separator is consisted the inner tube, helical slope plate and the three nozzles on tops are placed in a vertical cylindrical tank. This report was considered as functions of stirring, separation and discharge of the mixed plastics in the experiments and numerical simulations.

With the progress of information processing technology such as AI and IoT, the arterial industry is expected to make a big change by automation and efficiency, and its application to the vein industry is not attracting attention. The situation surrounding the industry is changing day by day, and the demand for automation and labor saving is increasing.

Electric vehicles (EVs) are getting attention to mitigate CO₂ emissions from the transportation sector in the world. However, EVs emit CO₂ throughout their life, and it is important to evaluate total amount of CO₂ emission as the lifecycle emission. In particular, large amounts of electricity are used to manufacture lithium-ion batteries. Reducing CO₂ emissions during the life cycle can be expected by improving the battery performance. Therefore, the aim of this study is to evaluate the lifecycle CO₂ emissions of lithium-ion batteries for EVs according to the Life Cycle Assessment (LCA) framework, taking into consideration the improvement of battery performance.

To find the quantitative evaluation methods for Environmental Activities by the companies, we tried to analyze the CSR using the correlation analysis and text mining. As a result, we found a quantitative trend toward companies with superior initiatives. To develop this, information disclosure activities should be promoted in the future.

In biogas power generation from sewage sludge, the amount of sludge generated determines the scale of the sewage farm and power generation, however the amount of sludge generated is affected by population change. In this study, taking Yamagata prefecture as an example, we evaluated the economic feasibility of biogas power generation, taking population change into account. As a result, it was found that the cost of treating digestive sludge was the highest among all treatment costs, including power generation, and that a decrease in sludge generation due to a decrease in population had a greater impact on reducing the cost of treating digestive sludge than a decrease in income from electricity sales.

Since the start of the COVID-19, people have become increasingly conscious of indoor air quality. Therefore, in order to investigate and improve the indoor thermal and air environment, we measured and evaluated air temperature, relative humidity and carbon dioxide concentration in a laboratory in Tokyo from March to May 2022. It is also proposed that the indoor air environment can be better predicted by making visualization of the number and behavior of people in the room using AI thermal cameras.