In a case study of a mixed dry field and dairy farming area in Hokkaido, we used a questionnaire to ascertain how farmers manage and use livestock waste, straw and other organic resources. Then, from a material balance perspective, we attempted to assess the supply-demand balance of organic resources between raising livestock and dry-field farming.
We found that the local cyclical use of composted livestock waste by dry-field farmers has made little progress, primarily due to a quality problem created by weed seeds mixed into the compost and the pattern that the more cattle a dairy farmer has, the smaller the amount of farmland available per head, causing a greater tendency to purchase straw and other resources from outside the area. This creates an input-output imbalance that increases the environmental burden.
In addition, this study confirmed that the appropriate local cyclical use of resources requires securing about 1 ha of feed-growing land per cow. Moreover, when ascertaining the environmental burdens of farms, applying a method based on the farm gate balance method, which uses data from production history ledgers, was found to be effective.

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Although waste management has contributed to improved levels of public hygiene, Japan still does not fully appreciate how sanitation conditions have stabilized at these higher levels. Future intermediate treatment systems must be planned in accordance with historical evaluation that takes into consideration measures for improvement of public hygiene. Moreover, with regard to technical assistance to developing countries, it is very important to highlight and explain the different roles waste management can play in the improvement of public hygiene. This study investigates the relationship between public hygiene and waste management, especially in the field of municipal solid waste (MSW) treatment. Results indicate that MSW management has contributed greatly to the improvement of public hygiene as well as water supply services and sewage treatment. In particular, measures adopted under the Public Cleansing Law of the Waste Disposal Act have proved to be quite successful, and nationwide construction projects for MSW incinerators, since around 1975, have also been instrumental in improving public hygiene.

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Since the Act for Recycling of Specified Kinds of Home Appliances was put into effect in 2001, Japan consumer electronic manufacturers have had to assume responsibility for 50-60wt% recycling of all disposed household appliances. Also, in expectation of a future rise in required recycling rates, it will be necessary to develop new material recycling technologies for plastics. The purpose of this study is to uncover effective utilization methods for the various residual plastics that are collected from consumer electronic recycling plants, waste that is presently being reclaimed and incinerated. The paper evaluates the relationship between contamination amounts and the mechanical properties of recycled polypropylene sorted from a mixture of residual plastics from waste household appliances. The purity of the recycled PP was 99.8% or more. The mechanical properties and the coefficient of variation for the mechanical properties of the recycled PP were almost equal to that of virgin PP. Due to the fact that some metal remains in the recycled PP, it is necessary to add a metal deactivator to the recycled PP in order to obtain a heat resistance comparable to that of virgin PP.

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Used fiberboard is difficult to recycle for wood material because it contains much adhesive and the fiber is deterioration. A great amount of lignocellulosic waste is generated in the fiberboard production process. In this study, the potential of used fiberboard as a molecular material through the application of a phase-separation system was examined.
Fiberboard was separated rapidly and quantiatively into carbohydrates and lignophenols through a phase-separation system composed of phenol derivatives and acid. Although plant cell walls form an interpenetrating polymer network (IPN) structure, fibrillated lignocellulosics had high accessibility for the reagents and allowed carbohydrates to be hydrolyzed effectively. On the other hand, phenol grafting to native lignin was accelerated. The resulting lignophenols from fiberboard had almost the same properties as those from wood meal, although a slight amount of the urea-melamine resin adhesive component was contained in the lignophenol. These results indicate that fiberboard is preferable to ordinary wood as an aliphatic and aromatic material source, and that it should be adopted for molecular level recycling through a phase-separation system.

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A method to harden incineration ash using binder materials that have calcium and silica as the main components is proposed in this paper. Incineration ash is burnt at a relatively low temperature of 800 degrees. This form of ash includes many harmful heavy metals. A large amount of metallic aluminum is contained in the incineration ash of municipal waste. Considerable expansion is caused by the generation of hydrogen gas through the response of metallic aluminum and calcium hydroxide as a result of the hydration of cement. In this paper, a method to control the expansion with this hydrogen gas and to restrain the leaching of heavy metals is proposed. The final volume of the solidified body is almost the same as that of the untreated incineration ash. The leaching concentration of lead from the final solidification is 1/2500 of that from incineration ash. In this paper, the safety of the solidified body was evaluated using a bioassay and a tank leaching test with lead.

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Using two count data models and the ITCM (individual travel cost method), we have estimated factors that determine the consumers’ voluntary recycling behavior and social welfare. Our research showed that consumers are more likely to recycle drink boxes if they are already socially responsible and concerned about social norms, if they are faced with greater costs for shipping recyclable boxes, and also if they are women. Hence, our policy implies that reducing recycling costs will raise public interest in protecting the environment. When 1kg of drink boxes is recycled (by consumers), the consumer surplus is equal to 234.79 yen.

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