When biogas is used it is needed to remove hydrogen sulfide economically and efficiently, it is thought that biological desulfurization using microbes in digested slurry is effective. However, detailed examination on the usage of digested slurry has not been reported. The objective of this study is to clarify the most effective arrangement for desulfurization when using digested slurry in small scale experiments. The 0.24 m³ reaction pipe made of PVC was used as an experimental equipment, and carriers were installed inside. Digested slurry was sprayed into the equipment by a nozzle using a pump. Hydrogen sulfide concentration was measured before and after the desulfurization by a densimeter, and the effect was evaluated by desulfurization rate. The system of filling the carrier obtained high desulfurization rate, and improved the effect by combining a spray system. This result suggested that contant efficiency between biogas and digested slurry was raised by using the fine mists generated from spraying digested slurry and it became possible to supply moisture and nutrition on the surface of carriers effectively.

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The effects of organic fertilizer on methane emission and rice growth in the acidic low nutrient soil of Thailand and investigated. Treatment of straw and cow dung with chemical fertilizer further increased methane emission above levels achieved by treatment of conventional compost and green compost (Sesbania rostrata) along with chemical fertilizer or by chemical fertilizer only. The maximum methane emission was 15.2 mg/(m²·h) with the application of straw and chemical fertilizer. During methane emission, development of white roots and growth of rice not suppressed. Biomass above ground and grain yield are positively correlated with high methane emission. In addition, organic matter and soil elements such as phosphorous, potassium and total nitrogen were higher in soil with straw and cow dung treatments demonstrating a positive correlation with high methane emission.

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Whole crop silage (WCRS) production is associated with the greenhouse gas (GHG) emissions because rice cultivation is a major source of methane (CH₄) and nitrous oxide (N₂O). However, few studies addressed the GHG emission from WCRS production system and compared enviromental performance to imported hay (IH) production system. The objectives of this study were to evaluate the GHG emissions of WCRS production system with different mechanized systems at the cases in Chiba using life cycle assessment method and to compare the GHG emissions with IH production systems. The WCRS production system evaluated were three systems of different harvesting machineries according to the production system at Chiba. Using machineries at three systems were a cutting role baler and self-propelled bale wrapper (CBS), a mower, role baler and self-propelled bale wrapper (MRS) and a mower conditioner, role baler and bale wrapper (MRW). The GHG emissions of IH production system were estimated by the mean of GHG emissions from eight states hay production systems and N₂O emission from the U.S. agricultural land. The GHG emissions assessed were: carbon dioxide (CO₂), CH₄ and N₂O from energy use, chemical use and land use. Two functional units were used to express impact of the WCRS production system: operations of 10 a rice paddy fields and total digestible nutrients (TDN) yield at 10 a rice paddy fields. GHG emissions at CBS and MRW were similar to 720-860 kg-CO₂eq/10a. Because harvested area was small at MRS, GHG emissions were 1720-1860 kg-CO₂eq/10a. GHG emissions of IH production system were 950-1630 kg-CO₂eq, varied according to hay yields, production area, N₂O emission from land use and CO₂ emission from transportation. Compared with IH production system at mean transportation distance. The GHG emissions at WCRS production system with CBS and MRW were low 330-620 kg-CO₂eq/10a. Besides, bacause large impact of GHG emissions at WCRS production system was caused by CH₄ from paddy fields and CO₂ from machineries production, suitable water control at paddy fields and effective utilization of machineries with adequate land area and intensive machinery use were considered important measures to mitigate GHG emissions from WCRS production systems.

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Assuming a bio-ethanol production facility using rice straw, characteristics of field-to-facility transportation were examined through simulation modeling and trial calculations. The conversion rate from straw to ethanol, the quantity of straw collected, and the ratio of the field area to that around the facility all affected the fuel consumption, the number of trucks needed, and other factors.Standard conditions were assumed based on reported data and actual observations: 15 ML/yr ethanol production, 0.3 kL output of ethanol from 1 t of dry straw, 53.6 d/yr working days, 2.7 t truck load capacity, and 0.128 as the ratio of field to the area around the facility. The calculation results revealed that a quantity of 50 kt dry straw necessitated the following: 2.78 L fuel consumption for transportation of 1 t of dry straw, 109.5 trucks, and a 19.1 km collection area radius.The total travel distance was found to be proportional to the quantity of straw to the 1.5 power, but inversely proportional to the ratio of he 0.5 power. Furthermore, the fuel consumption for transportation was found to be proportional to the quantity of straw to the 0.5 power, but inversely proportional to the ratio of field to the 0.5 power.The rate of increase in the necessary number of trucks collecting straw increases with the decrease in the ratio of the field to the area around the facility.

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In the paper, the physical properties of cooked noodles made from a blend of kirara 397, one kind of Japonica rice used more popularly in Japan as main materials for noodles, and Yumetoiro rice with high amylase content, used as additive in the blend were studies to improve the quality of noodles from kirara 397. The results showed that: firstly, the tensile stress and tensile strain of cooked noodles from the blend were bigger than those of cooked noodles from 100 % Kirara 397, and the loss tangent of cooked noodles from the blend was smaller as well. These meant the cooked noodles from the blend had a stronger gel-network structure than those from pure Kirara 397. Therefore the physical properties of cooked noodles are much improved. Secondly, the rising speed of the Storage moduli (G′) and loss moduli (G″) of cooked noodles from the blend were more easily retrograded. Thirdly, from the point of sensory evalution, the cooking noodles from the blend were better than those from 100 % Kirara 397.

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Rice husks with several water contents were milled and sieved for a numerical evaluation of their particle distributions. The distribution for longer milling period shifted to smaller particle size, however changes in the parameter of the approximation to the Rosin-Rammler distribution had no dependence on the period. This was resulted from particular micro structures of the powder under 100 μm were uncrushed and it seemed that an accumulation of the structures affected to the distribution curbs. A new numerical method, which was total of the products of mesh size and weight percentages of the sieved powders in the mesh was applied and evaluated the distribution. Asa result, the changes in distributions for milling periods can be estimated by the numerical values. It was also evaluated that the particle distributions from lower water content material shifted to smaller particle size, if the milling time was constant.

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