Monitoring of the numbers and production dates of waste PET Bottles (mineral water/soft drink), which wash up onto the beaches of Tottori in Japan, was carried out every month over a period of seven years. A total of 56,306 bottles (560 chinese bottles with legible production dates) were collected and analyzed. The analysis indicates that these littered bottles flow into the sea from Taiwan and southern China around April to June and are washed up onto Tottori’s beaches mainly during the months of August and September. Most bottles from other areas of China are transported to the sea via rivers around July and August, and are washed up onto the shores around October and November. The bottles from Southeast Asia are washed up from August through November. On the whole, the floating bottles from the East China Sea drift into the Sea of Japan from August through November. Bottles originating in Korea flow into the sea in summer and drift toward the north. The Korean bottles mix with bottles from Russia, then drift southward pushed along by northerly autumnal winds. These bottles are then washed up onto the beaches in Tottori around November and January. Thus, it was revealed that the drift pathways for these waste PET bottles are governed by the East Asian monsoon cycle and the corresponding sea currents.

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The detergent fiber method has been widely employed for the analysis of lignocellulose ingredients, which are very important for biomass research. However, its application is complicated and a large amount of waste liquid is discharged. Therefore, in this study, a quick and simple analysis of lignocellulose ingredients by thermogravimetric analysis was proposed and examined. The differences in thermal decomposition characteristics of hemicellulose, cellulose and lignin were used for the quantitative analysis of lignocellulose ingredients. The practical feasibility of a proposed method as a simple and quick analytical method with no waste fluid discharge was shown by a series of experimental examinations.

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In 1988, a landfill closure law went into effect in Japan. The law stipulates requirements related to landfill closure conditions such as leachate quality, landfill gas conditions, and the interior temperature of the landfill site. The landfill closure standard influences landfill stabilization decision tools. Presumably, the calories of the leachate reflect the landfill biodegradation and its chemical reactions. The landfill stabilization decision tools and closure decisions are affected by the leachate temperature and quality. The total calories from discharged leachate reflect heat generation conditions inside the landfill and its waste stabilization situation.
Additionally, relations among the pollutant load amounts in leachate, the landfilled waste amount, and the landfill layer depth are clarified through caloric measurements. Results clarified that the leachate quality, temperature, and amount are useful but simple parameters for decision tools used to assess landfill stabilization and closure.

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Based on a life cycle assessment, this study evaluates changes in environmental impact as a result of the introduction of a clay roof tile recycling system. The clay roof tile is a ceramic product that must be crushed in order to be recycled. Our case study focuses on a recycling system introduced in Nagoya City. Energy consumption, CO₂ emission, NO_x emission, SO_x emission and waste emission were selected as the environmental loads for this study. The results of our inventory analysis reveal that while NO_x emission, SO_x emission and waste emissions saw a decrease under this system, energy consumption and CO₂ emissions increased. We carried out integrated analysis using several methods. LIME (Life-cycle Impact Assessment Method based on Endpoint Modeling) results showed that this recycling system would cause a decrease in the integrated environmental loads. On the other hand, results achieved by Eco-indicator 95 and EPS (Eco-Scarcity Method) showed increased environmental loads. We also conducted an estimate of the total discharge amount of waste roof tiles in Nagoya City using GIS, then analyzed material balance in the recycling system. Results showed that only the system in Nagoya City resulted in an increase of 0.03% CO₂ emission and achieved 21% of the reduction target for final industrial waste discharge throughout Aichi Prefecture.

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In the present work, experiments on the non-thermal plasma decomposition of isobutanol, which is a particularly malodorous volatile organic compound, were conducted by using a wire-in-tube plasma reactor in an N₂-O₂ atmosphere (N₂: balance gas). The initial concentration of isobutanol was fixed at 100 ppm and the concentration of O₂ and the relative humidity ranged from 0-75vol% and 0-60%, respectively, at a total gas flow rate of 200×10⁻⁶ m³· min⁻¹ and a reaction temperature of 298K. The influence of coexisting O₂ and H₂O on the plasma decomposition of isobutanol was studied on the basis of the experimental results obtained.
As a result, under these experimental conditions, it was found that the ratio of decomposition of isobutanol decreased with an increase in O₂ concentration and increased with an increase in relative humidity. An isobutanol decomposition ratio of 100% was obtained in a reaction atmosphere of O₂ 20vol% and a relative humidity of 60% at a specific input energy higher than 0.90MJ · m⁻³. From this finding, it is thought that OH radicals produced from the plasma decomposition of H₂O enhanced the plasma decomposition of isobutanol.

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Fishery wastes (scallop remnants and squid viscera) were decomposed and their volumes were reduced using microbial treatment. Chipped larch trimmings were mixed with buckwheat husks for use as the microbial supporting medium. Functional microbes (Bacillus spp., Yarrowia lipolytica) that have the ability to decompose proteins and lipids were added to the supporting medium. By adding functional microbes, the decomposition rates of the scallop remnants and squid viscera were increased. The decomposition rates of these fishery wastes were measured and the optimum temperature, pH and water content conditions for continuous treatment were examined.

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