The study focuses on the design of renewable energy systems introducing biomass resources for a rural area in Japan. In an energy-economic model, woody biomass and animal manure (livestock and poultry manure) have been introduced to supply stable power, combining with wind and PV etc. Intermittency of climate conditions and the changes in demand of electricity are carefully considered to examine cost effec-tive systems for the area. As a result, we have found that gasification of woody biomass can supply electric-ity at a reasonable cost, and the biogasification of animal manure becomes cost effective provided inverse onerous contract of the waste is available. The renewable energy system reduces the carbon emissions by 65%, and reduces the annual cost of the entire system by 15%.

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In recent years, changes in the family composition and lifestyles have increased the use of automatic washing machines that save energy and are less environmentally harmful. These factors, along with new developments such as compact powdered detergent, have led to changes in consumer home-laundry behav-ior. In place of a typical environmental life cycle product assessment (called ISO-LCA), we proposed the application of social life cycle assessment (called social LCA) as part of a comprehensive study of consumer behavior related to home laundry. In this study, we examined plans to reduce environmental impact during the overall life cycle, including the wear cycle of clothes, through the application of social LCA to two types of washing machines: the pulsator type and the drum type. We examined the effect of the mechanical action of pulsator-type and drum-type washing machines by measuring detergency using artificially soiled test clothes (JIS C 9606), by evaluating the raveling of MA test pieces (Technology Institute, Denmark), and by determining the shrinkage percentage of shirt collars. In addition, we measured the consumption of elec-tricity and the water volumes of the washing machines in a single cycle. Our study of the social LCA of the home laundry process has clarified that CO₂ emissions during machine use are much greater than CO₂ emissions during the actual manufacture of either type of washing machine. In addition, it has been clarified that the pulsator-type washing machine can reduce total CO₂ emissions to a greater extent than the drum-type washing machine over its lifecycle with an increasing weight of clothes washed per load. Of all lifecycle stages, levels of CO₂ emissions are highest during the period in which the wears phase. Furthermore, we found that the total CO₂ emissions increased to the greatest extent if the drying process is included.

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The demand pattern with a high time resolution is indispensable to examine and design an appropriate distributed energy system for residential sector. This paper describes energy consumption pattern with high resolution in the apartment of a cold district which consists of 34 households. The heat-power ratio of energy demand changes from about two in summer to about ten in winter. The maximum electric power demand is about 1kW/household and the minimum is about 200W/household. The estimated minimum capacity of electricity storage device is 80wh/household. The several simulation of distributed systems based on the survey of energy demand is carried out. By the system which consists of SOFC and heat pump, as a result of operating heat pump in accordance with heat demand, energy consumption was reducible 26%. Further, as a result of enlarging the generator of the system and operated to meet electric power and heat demand, energy consumption was cut down further and 95% of total electric power demand has been supplied by the distrib-uted system. Furthermore, in the system which added the electricity storage device of the capacity of 10kWh, it turns out that it is possible to supply 100% of electricity demand.

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The coal pyrolysis behavior, that is the initial reaction in the coal gasifier, is investigated to clarify phenomena in the gasifier of IGCC. Since pressurized entrained flow gasifiers are adopted for the almost all IGCC processes for large-scale power generation and these gasifiers are operated at a pressurized reducing atmosphere and high temperature, the influence of the pyrolysis temperature and pressure on the composi-tion and properties of the pyrolysis product was examined. As a result of rapid pyrolysis tests for three types of bituminous or semi-bituminous coal using a pressurized drop tube furnace facility (PDTF) in nitro-gen gas flow at high temperatures of over 1000 degrees Celsius and at high pressures of under 2.1MPa, the yield of the volatilized gas components decreased when pyrolysis pressure increased. The product char of pyrolysis tests was formed many more than fixed carbon in coal, and contained a large amount of fine particulates of carbon like coke or soot. For some coal types, the CO₂ gasification reactivity of the fine particulates was so lower than that of the char particles originated from fixed carbon that it could be said that the clarification of the formation mechanism of coke is important. The amount of the coke particulates existing outside char particles at pressurized pyrolysis tests was less than that of the coke particulates at 0.15 MPa because of deceleration of volatilization at primary pyrolysis reactions. Furthermore, it was con-firmed that the coke particulates were also formed at the conditions where gasifying agent existed like the inside of gasifiers.

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Influences of external surface and total areas of some H-mordenites (HM) were examined to elucidate the role of external acid sites in the isopropylation of biphenyl (BP).
The several types of HM (SiO₂/Al₂O₃ ratio: 12-19; BET surface area 480-500 m²/g; external surface area: 0.1-25m²/g) were obtained commercially or synthesized by the methods referred to the literature for ZSM-5 and other zeolites. The selectivity for 4, 4'-diisopropylbiphenyl (4, 4'-DIPB) was almost constant for all HMs in the isopropylation; however, the catalytic activity was varied by samples.
H-Mordenites with different particle size HM [a] (average particle size 2μm; SiO₂/Al₂O₃=18.7; external surface area: 17m²/g) and HM [b] (average particle size 1μm; SiO₂/Al₂O₃=15.7; external surface area: 25m₂/g) were dealuminated by the combination of steam treatment at 600°C and acid leaching at 80°C. The selectiv-ity for 4, 4'-DIPB was in the similar level for both series of HMs in the range of SiO₂/Al₂O₃ ratio from 20 to 400. However, the catalytic activity was varied with the ratio.
These results from two types of HMs show that selective formation of 4, 4'-DIPB occurred inside the pores of HMs, that the external acid sites did not play an important role on the shape-selectivity, and that catalytic activities for the isopropylation were influenced by external surface area.

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