In order to apply a leachate circulation system, which is effective in land reclamation using domestic wastes, to seaside land reclamation with industrial wastes, a verification experiment with a pilot plant was performed. By circulating the leachate to create a semi-aerobic-anaerobic condition, the concentrations of COD, total organic carbon (TOC) and total nitrogen (T-N) in the leachate were reduced to 14.6-16.6%, 32.3-38.3% and 24.8-28.3%, respectively, and the outflow of leachate was reduced to 77.6-91.5%. The total amount of outflow of COD, TOC and T-N were reduced to 19.8-28.2%, 8.3-47.8% and 23.5-25.6%, respectively, and a sudden change of leachate quality, which was not desirable in the treatment, was prevented. This system was also effective against odor sources, such as ammonium and sulfide, and hazardous substances, such as heavy metals or total organohalogen compounds.

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In the Johkasou system (an on-site domestic wastewater treatment system), excess sludge is withdrawn and transported to a human excrement treatment facility. The operation of this system occupies a large part of the total treatment cost. Therefore, it is beneficial for reducing the production of excess in the system. The work presented in this paper focuses on the development of aerobic digesters for this purpose. Two types of reactors were set-up : Reactor-A was equipped with a filter unit for sludge separation and Reactor-B was a kind of submerged bio-filter process.
The sludge obtained from an anaerobic tank in a Johkasou system was fed once a day into the reactors at HRT = 10 days. Both reactors retained about 10,000 mg · L^-1 of MLSS. Effective solid separation performance was obtained, and the effluent contained about 15% of the fed SS.
After approximately 100 days of operation from start-up, the SS reduction ratios ranged from 30 to 40%. However, the SS reduction ratios in the first half of the period were lower due to the acclimation of biomass in the reactors. COD_Mn was effectively removed at 86-88% and the COD_Mn level of the effluent was similar to, or lower than, that of raw domestic wastewater.

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Shredder residues derived from ELV (End of Life Vehicles), home electrical appliances, automatic vending machines, and other products were characterized in terms of composition, heating value, and other parameters. Samples were collected from several shredding facilities that use different processes.
Physical compositions are different for each kind of shredded product. While hard plastics account for 70 percent of the residue in electrical appliances, various types of combustible components are included in the residue of ELV. Material recycling, therefore, is difficult when mixed products are shredded all together. Due to the high ash content in small particles of ELV residue, sieve separation effectively reduces ash content, but does not improve material recovery because of uniform composition among different size fractions. Since the copper content in shredder residues analyzed in this study are comparable to high-quality natural ore, recovery of copper is recommended for all types of waste products.

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Buckwheat husks were treated by cooking with water followed by carbonization. By cooking buckwheat with water, about 600 mg of rutin, a well-known bioactive polyphenol, was extracted per kilogram of husks. After cooking, the wet buckwheat husks were carbonized and yielded useful char and vinegar.

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Anaerobic digestion is an important technology for production of renewable energy from municipal solid waste (MSW). An MSW anaerobic digester usually transforms 70% of charged MSW to biogas and generates 30% residue. Wastewater containing high concentrations of ammonia is also produced. The necessary treatment of those residual materials reduces the overall economic efficiency of anaerobic digesters. We established hyper-thermophilic (80°C) anaerobic digesting sludge that includes more than four hyper-thermophilic microbes from hot springs. Hydrolysis enzyme activity tests revealed that hyper-thermophilic sludge solubilized MSW four-times faster at 80°C than anaerobic digestion sludge at 55°C. The total effects of this sludge were tested using a semi-continuous feed bench-scale digester. Results show that the digestion rate improved 4.3% and ammonia concentration of wastewater was lowered to half by ammonia stripping. The temperature and pH of hyper-thermophilic hydrolysis were suitable for ammonia stripping. Microbial flora of this hyper-thermal digester were characterized using PCR-DGGE. Some species of thermophilic bacteria were found from hyper-thermal hydrolytic sludge at 80°C, which do not usually exist in anaerobic digesters at 37°C or 55°C.

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Asbestos waste has been disposed of in landfills for many years. However, since landfills will be unable to accept more waste in 2.5 to 4.5 years, we need new disposal methods for asbestos. This study reports the results of laboratory experiments that examined the disposal of asbestos and waste that contains asbestos by melting with fly ash and ash at temperatures below 1500°C.
The proportions of chrysotile, ash and fly ash influenced the melting of chrysotile in a test of 30 minutes at a temperature of 1300°C. The ash used in this experiment included much Fe₂O₃, and the fly ash used in this experiment had a lot of CaO. SiO₂ also existed in the ash, but the amount depended on the type and volume of waste. Chrysotile contains much Si. Melting is possible when the proportions of SiO₂, Fe₂O₃ and CaO are suitable. Using ash and fly ash, we were able to melt 40% pure chrysotile.

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