As one of the countermeasures against global warming, it is effective to make use of wood resources that serve as carbon storage and improve energy-saving efficiency of buildings. In this study, it is examined how the wall composition of a wooden house affects indoor thermal environments and its energy-saving effects. Three types of wooden wall panels with different compositions are used to examine each type's thermo-physical properties by JIS-compliant tests as well as large-scale tests with experimental buildings. Moreover, power consumption of a heated building was also measured in order to make clear the effect of the wall composition of a wooden house on energy-saving. The obtained results are as follows : 1. Coefficients of overall heat transmission were qualitatively larger in the following order : general mud wall > wall composed of wood and mud > wall primarily composed of heat insulating material. 2. The air-conditioner's power consumption was larger in the following order : house with mud walls > house with walls composed of wood and mud > insulation-type house. As the temperature difference between indoors and outdoors increased, this tendency became more notable. 3. In the cases of insulation-type houses, the ratio of electric power consumption for heating to temperature difference between indoors and outdoors was generally constant, while in the case of a house with walls composed of wood and mud or with mud walls, the ratio was not constant, denoting the effect of heat capacity. 4. The compound wall of Japanese cedar and mud showed a better heat insulation property than the mud wall, and its energy-saving effect was improved.

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The characterization of the process of separating cellulose fibers from wood by using L-lactic acid was investigated. Sugi (Cryptmeria Japonica) were cooked with L-lactic acid at 200°C for 1hr to be separated as pulp-like fibers and liquefied wood components. The pulp-like fibers were analyzed with molecular weight, SEM, X-Ray diffractions, IR, and ¹³C NMR. Molecular weight was about 1.1×10⁶-1.5×10⁶. The crystals of the pulp-like fibers were type I and the crystallinity was 23-25%. The pulp-like fibers were esterified with L-lactic acid. It was concluded that the cooking the wood with L-lactic acid was a significant separation system, taht the delignification occurred by acid hydrolysis and decomposition, and that esterified cellulose derivatives were produced from wood material.

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The waste substrate from sawdust-based cultivation of Heicium erinaceum was reused. This process was conducted three times. Even when the waste substrate was reused three times, the yield of fruiting bodies was equal to that of fresh medium. However, the yield of the 1st waste substrate was the best of all waste substrate media, and the yields of subsequent waste substrate media decreased with recycling times. The yield of the 1st or 2nd waste substrate medium was 1.3-1.4 times that of the fresh medium. The content of low molecular α-glucan and β-glucan of the 1st or 2nd waste substrate medium increased and the C-N ratio of the 1st or 2nd waste substrate medium decreased. These results suggest that low-molecular glucan and N sources contribute to increased fruiting bodies. It was clear that the 1st and 2nd waste substrates were useful for the cultivation of Heicium erinaceum.

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Nickel-loaded wood charcoal obtained by catalytic carbonization at 900°C was subjected to pulverization followed by acid-soaking to examine the crystallinity of the carbon and the pore structure, in addition to the content of the metal. Obtained results showed enhancement of the quality or performance of the resulting char as electro-conductive carbon and liquid phase adsorbent for macromolecules, with about 99% removal of the metal. This aspect explains that incorporation of such post-treatments into the manufacturing process of carbon products is greatly advantageous. Furthermore, useful information on the fine structure of this charcoal, particularly the mesopore structure, could be drawn from the relevant analyses.

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The “Ball-Vibration Simultaneous Saccharification and Fermentation system” was tested for more effective conversion of the spent Maitake (Grifola frondosa) culture medium to ethanol. This system converts biomass to ethanol in one vessel containing cellulase, yeast and small balls with vibration. In this system, high ethanol yield was obtained, but ethanol fermentation was inhibited during continuous vibration. This inhibition was relieved by using intermittent ball vibration which alternates stationary culture and vibrating culture, and consequently ethanol fermentation time was significantly decreased and ethanol yield was 1.3 times higher than for vibration without balls. Therefore, the Ball-Vibration SSF system was effective for increased ethanol conversion rate of the spent Maitake culture medium. It is likely that this system would also be effective for ethanol conversion of various types of biomass.

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In order to incinerate the swine feces, which causes subterranean water pollution in the Miyakonojyo basin, low quality charcoal was used as auxiliary fuel. Through this method, swine feces which do not self-burn can be converted into an energy source. From the viewpoint of the energy yield, it is preferable that the processing temperature of the charcoal is less than 300°C. There are some advantages in mixing swine feces and charcoal ; the mixture produces sufficient heat energy for self-burning, the bad odor of feces decreases, the drying of feces becomes easier and faster, and the handling of feces is improved. A technical scale experiment for the continuous incineration of the feces-charcoal mixture was done for 48 hours. During the experiment, the amount of steam generated from the system was measured. The result revealed that the quantity of the steam is insufficient for high-temperature kiln-drying system such as 120°C, but would be useful for a mild-temperature kiln-drying system. Because the energy efficiency is quite high, it is expected that the direct burning of wood biomass, though it is low-technology, will contribute to the large saving of fossil fuel.

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The transportation cost of construction waste wood from a demolition spot to the intermediate treatment mill, the crush processing cost at the intermediate treatment mill, and the transportation cost of crushed chips to the recycling mill were estimated and ways to reduce those costs were discussed. The transportation cost of construction waste wood and of crushed chips was greatly reduced by increasing the number of round trips per day. The transportation cost of construction waste wood was about two times that of crushed chips. The transportation cost of crushed chips was greatly reduced by increasing the backhaul use rate when the section between an intermediate treatment mill and the recycling mill was a distant place allowing only about 1 round trip per day. The total transportation cost of construction waste wood and crushed chips was mainly influenced by the location of the intermediate treatment mill. The total transportation cost was estimated by each number of round trips of construction waste wood and crushed chips, and by the backhaul use rate of crushed chips. The crush processing cost was reduced greatly when the annual processing scale of the intermediate treatment mill was increased from 20000 t to 50000 t or 100000 t.

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