In addition to expansion of waste recycling efforts alone, even further reduction of waste is required if a society that can boast an environmentally sound material cycle is to be finally achieved. In light of such a requirement, most local governments have begun“Awareness Raising Programs, ”whereby they strongly appeal to residents, who discharge wast, for greater reduction and recycling of waste. The effectiveness of these programs are typically based on the distribution of information in the form of pamphlets and other educational materials. Local governments make good use of media, and develop strategies that back up their policies for greater understanding and efforts by residents. In order to better calculate the impact such approaches have on the actual amounts of waste from ordinary households, we have carefully examined the quantity of household waste and performed experiments on strategies taken up by local governments. In our results, we were able to confirm that the quantity of various component parts of waste has been reduced when local waste reduction campaigns are established and information is provided to citizens who are discharging waste. These impacts continued for more than four months and the reduction of waste generation has also endured.

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We developed a new treatment system for food waste and garbage using a two-phase methane fermentation system with aerobic solubilization. In a continuous 190-day experiment, we found that the aerobic solubilization process could handle a volumetric load of 80 to 100 kg-garbage/ (m³· day) and that the acidification process could be operated at an HRT of 1.2 day. The maximum volumetric load of the methane fermentation (EGSB) process was 9 kgCOD/ (m³· day) . In comparison with single-phase methane fermentation, this system has the advantages of shortening the HRT and making possible the discharge of treated water into the sewer system. However, we found that lipid matter accumulated in the acidification tank and suspended solids also accumulated in the EGSB reactor. Analysis of the fatty acids revealed that these originated from lipids contained in meat and seafood.

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The disposal of used dry batteries containing mercury in Japan led to fears of environmental contamination by mercury, becoming a major social issue in 1983. Many of the details of the behavior and characteristics of mercury from landfilled dry batteries are yet unknown.
This paper discusses an investigation of mercury leakage into the leachate and vaporization into the atmosphere, using a large-scaled lysimeter. The lysimeter was disassembled 10 years after the landfill was started, and the behavior of mercury inside the lysimeter investigated.
Results indicate that total mercury leaking into leachate over the 10-year period was no more than 0.1%, and atmospheric dispersion no more than 2 %. Disposal (vaporization) into the atmosphere through outgassing was therefore more important in the release of mercury into the environment. Mercury was found to have transferred from the dry batteries to the waste layers. Over 90% of the original mercury content remained in the landfill after the 10-year period, confirming that the substance does not leak into the landfill site easily.

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In waste processing, the gasification and melting system is effective in reducing the volume of ash and dioxin emission. For a more effective use of this system via the improvement of energy recovery and efficient usage of char as fuel, it is necessary to understand the pyrolysis behavior in the changes of Municipal Solid Waste (MSW) composition. In this study, we developed the pyrolysis reaction model of MSW which consists of typical chemical substances.
First, from MSW composition investigation, cellulose, xylan, lignin, polyethylene, polypropylene, polystyrene, and silicon dioxide were determined as representational substances of MSW. Secondly, their pyrolysis behavior, which were expressed with thermogravimetric (TG) curves were analyzed by a multireaction model, and the TG curves of the mixed samples of the representational substances were in good agreement with the weighted sum of the model TG curve of each representational substance. Finally, TG curves of MSW and refuse-derived fuels (RDF) were approximated with the weighted sum of the TG curve of the representational substances, and the composition calculated by the proposed model and the real composition were in good agreement with of all MSW and RDF.

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In order to study the degradation of biodegradable plastics, 8×2.5cm² samples of five kinds of plastic sheets (PBSA, PLA, PHB/V, PCL, PBS) were buried with two types of mixed solid waste (A: Incineration ash+crushed waste, B: A+compost) . Samples of each kind of solid waste were kept in 350 mL pots at 25 and 37°C. The degradation rate was measured by the reduction in area and the plastic was examined using SEM. We made six findings. (1) Two types of degradation processes were observed: hole expansion aided by bacteria and crack formation caused by alkalis in the incineration ash. (2) Hole-expansion type degradation was promoted by increasing the temperature from 25 to 37°C or by adding compost to the ash. (3) The degradation rate of the biodegradable plastics in ash with a low organic content was similar to that in normal soil. (4) Degradability could be ranked from high to low as PBSA>PHB/V>PCL>PBS>PLA. (5) When microorganisms did not affect the biodegradable plastics, alkalis produced cracks in the plastics. (6) PBSA and PCL probably increase microbial activity in mixed solid waste.

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Conflicts have frequently arisen in the process of facility siting for industrial waste management facilities (IWMFs) which are undesirable to residents who are living nearby. Since, from the viewpoint of environmental justice, it would not be appropriate for these sites to have disproportionate spatial distribution, their spatial distributions were examined quantitatively. In addition to the IWMFs, the spatial distribution of illegal industrial waste dumping sites, also causing social problems, was also analyzed. This paper concerns landfill sites, intermediate processing facilities (incineration facilities, shredding/crushing facilities, dewatering facilities), and illegal dumping sites for nine prefectures in the Kanto region, which were counted by municipality units, and investigates trends for each locality using the Geographical Information System (GIS) . Our results showed that through a statistical analysis for positive spatial autocorrelation, the significant level of 1% existed in the distribution which therefore indicates that there are spatially uneven distributions. In addition, a similarity between the spatial distribution of landfill and illegal dumping sites was observed at a significant level of 1 %. This finding makes it clear that similar factors could possibly exist, and result in uneven siting for both of these types of facilities.

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We have investigated the chemical composition and mineral species of some precipitations and electrostatic precipitator ash from MSW stoker incinerator facilities. Results of this investigation could be made use of for the processing of waste in the dismantling of incinerator facilities. Samples were analyzed using EDXRF method. EDXRF results showed that major elements of samples were Si, Ti, Al, Fe, Mg, Ca, Na, K, S, P, Cl. Mineral species were identified using XRD method and TGDTA method. Mineral species identified were Anorthite, Gehlenite, Quartz, Hematite, Lime, Portlandite, Hydrocalumite, CaClOH, Ca (ClO) ₂⋅4 H₂O, Halite, Sylvite, Calcite and Anhydrite. In addition, Akermanite, Perovskite, Farringtonite and Mg₂P₂O₇, were presumed to be possible minerals. Sprayed Portlandite was transformed into CaClOH and Ca (ClO) ₂⋅4H₂O.

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Although various routes for waste wood recycling have been examined from the viewpoint of reductions in waste disposal and effective use of resources, behavior of wood preservatives which may flow into waste wood materials, and related compounds, in the recycling processes have not been fully elucidated upon. The behavior of heavy metals, chlorinated hydrocarbons and polycyclic aromatic hydrocarbons (PAHs) were surveyed in the manufacturing process of construction material (particle board) using waste wood chips. It was found that waste wood treated with pentachlorophenol (PCP) or creosote might flow into the crude chips. Also, there was formation of PCDD/DFs which were contained as impurities of PCP during the manufacturing process. Consequently, chemical substances originating in those behaviors were contained in the final products. In order to promote the environmentally sound management of waste wood, verification of the chemical levels in final products, through examination of a risk control policy, will be required.

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