The barley-, sweet potato-, rice sho-chu post-distillation slurry are organic acid rich waste which annually produced from sho-chu manufactures. The biological hydrogen production from sweet potato sho-chupost-distillation slurry by newly isolated bacteria was demonstrated. The bacteria that can produce hydrogen were isolated from 187 location sites. The anaerobic bacterium, Clostridium sp.JPCC H-3 was found the highest hydrogen producer from Ametaki. The maximum hydrogen production rate of Clostridium sp.JPCC H-3 was obtained at 5.35±0.19ml/5ml-solution for 24hr under 37°C and dark conditions. It was 1.4 times higher than that of Clostridium butyricum NRBC3315 as comparative strain. Moreover, organic acids such as acetic acid and lactic acid were substrates for hydrogen production by Clostridium sp.JPCC H-3. The sweet potato sho-chu post-distillation slurry could be use substrates for hydrogen production and Clostridium sp.JPCC H-3 will be one of the suitable candidates for hydrogen production from sweet potato sho-chu postdistillation slurry.

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Despite efforts to decrease the environmental impact at a product level, the environmental impact at a household level is in danger of increasing due to the fact that the number of home appliances per household on the rise. Therefore, “Factor X” on home appliances at a household level in 2003 with respect to 1990, from the viewpoints of the prevention of global warming and the effective utilization of resources is simulated.The number of home appliances used in a household increased 1.2 times from 65 to 79, but since the GHG emissions over the life cycle per year was 0.64 times the former amount, dropping from 8456kg-CO2eq/year to 5383kg-CO2eq/year, and the non-circulating resources per year became 0.99 times the previous amount, dropping from 231kg/year to 228kg/year, the GHG Factor was 1.9 and the Resource Factor was 1.2. Although based on a restricted simulation model, these results could show the potential for realizing a “Sustainable Society” that involves the reduction of environmental impact at the same time as improving quality of life.

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Air-steam gasification of waste biomass was performed using a downdraft-fixed gasifier at atmospheric pressure and 1173K. The effect of a chemical property of waste biomass feedstock on the product distribution and product gas composition was statistically investigated. Twelve types of waste biomass and three types of model compounds of woody biomass were employed as feedstock. Gas, water soluble compound, water insoluble-acetone soluble compound, acetone insoluble compound, and char were obtained as products. Regardless of the variety of feedstock, the volatile matter content was the factor affecting the distribution to gas and product gas composition. The distribution to gas, i.e., the conversion to gas on a carbon basis, increased from 52.8 to 97.9C-mol% with an increase in the volatile matter content in the feedstock. The distributions to the water soluble compound, water insoluble-acetone soluble compound, and acetone insoluble compound were independent of the chemical property, and would be affected by the nitrogen and ash contents in the feedstock. The main product gas was H₂ (20-35mol%), CO (15-30mol%), CO₂ (20-35mol%), and CH₄ (5-10mol%). When the volatile matter content was more than 70wt%, the molar ratio of H₂ to CO in the product gas (H₂/CO) decreased with an increase in the volatile matter content, while the molar ratio of H₂ to CO₂ (H₂/CO₂) was approximately unity and independent of the chemical property.In waste biomass with a volatile matter content of 70-80wt%, syngas with the desired H₂/CO ratio for methanol synthesis was obtained. In waste biomass with a volatile matter content of more than 80wt%, syngas with the desired H₂/CO ratio for dimethyl ether (DME) synthesis was obtained.

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This report introduces five biomass gasification power generation plants in Europe, three nations, Swit-zerland, Austria and Germany, where the author visited November 2004. PYROFORCE in Switzerland used fixed bed gasification system with 200kW GE-Jenbacher gas engine. This gasification system promotes very little tar even as a fixed bed gasifier because of optimization of shape of reactor and airflow. Gassing in Austria uses internally circulating fluidized-bed gasification system. Characteristic of this system are to promote medium calorific gas because of using steam and to use combustion heat efficiently for gasification. This plant is equipped with 2000kW GE-Jenbacher gas engine. Electricity is sold for homes and factories, heat is supplied to regional heating system in the city. Future Energy GmbH and CHOREN GmbH in Ger-many operate the entrained bed gasification system. In Future Energy, there are three type entrained bed gasification systems for fuel types. CHOREN has established Carbo-V system with entrained bed with the charcoal fire pit. All of plants use woody biomass. Thus, the author thinks it difficult to transfer European techniques to Japan without modifications because of different surroundings. It is also needed to develop not alone technology, but policy to adopt biomass generation in Japan.

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