The effects of sludge treatment in animal manure composts on both carbon mineralization patterns, and the reduction of potassium and phosphate dissolution were examined in comparison with untreated composts and composts treated with poly-aluminum chloride.
1) Almost all of the potassium was dissolved by water out of the non-aluminum treated composts whereas, about 75% of the potassium was dissolved out of the aluminum treated ones.
2) The amounts of easily soluble phosphates in the sludge treated composts were 24-35% lower than those of untreated control composts. Similarly, those amounts in the poly-aluminum chloride treated composts were 38-42% lower.
3) The potentially decomposable carbon in proportion to the total carbon in the control composts, in the sludge treated composts and in the poly-aluminum chloride treated composts were 26.1-26.3%, 22.6-22.8% and 17.4-21.1%, respectively.
The amounts of water-soluble potassium and of easily dissoluble phosphate, and the carbon mineralization of composts were reduced by the addition of poly-aluminum chloride, but this addition tended to result in incomplete fermentation. On the other hand, the addition of sludge also reduced the amounts of water-soluble potassium and easily dissoluble phosphate, and the carbon mineralization of composts, but without any significant effect on the fermentation.

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Experiments were conducted to confirm the effect of actinomycetes seed addition on high-rate composting and the suppression of odor from shredded garbage by the measuring of evolved lower fatty acids and so on. Four kinds of samples were used : Run A was a dried garbage sample with pH adjustment and initial moisture content of 68%; Run B was a sample with actinomycetes seeding content of 52%, which was the dry weight standard, and initial moisture content of 69%; Run C was a sample with actinomycetes seeding content of 58% and initial moisture content of 66% ; and Run D was a sample with actinomycetes seeding content of 70% and initial moisture content of 61%. A standard-issue, practical fermentor (in both scale and structure) was used. Each run was carried out for around 7 days on garbage sediment 300 mm in height under natural aeration and with periodic turning over using a scoop-type mixer. The greater the content of actinomycetes seeding was, as in Run A, B, C and D, the faster the fermentation process was promoted, at a high temperature. In addition, in the early stage maximum concentrations of lower fatty acids appeared ; these values were not a constant tendency in the four conditions. Furthermore, maximum concentrations of odor appeared in the early stage ; these values were similar in the four conditions. During the period of the experiments, the lower the moisture content was, the larger was the volume of actinomycetes retained in the initial samples. Whether the volume of actinomycetes was large or small made no difference in the effectiveness on degradation of lower fatty acids. These results suggest that the prepared seeding material is effective in the promotion of fermentation and the early decrease of odor formation, and actinomycetes themselves do not have a practical effect on the presuppression of odor formation.

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In order to promote the use of waste molten slag as a construction material, the long-term environmental impact of slag must be appropriately evaluated. Slag is used in a variety of ways including as a roadbed material, as a concrete aggregate, etc. An evaluation method is required to reflect the different conditions of utilization. As for monolithic materials, diffusion tests have been used as a tool for estimating long-term environmental impact. In this paper, an application method for the diffusion test has been examined considering those cases where slag has been used directly as a roadbed material and as an aggregate in a mortar.
The main results of the tests were : 1) An improved analysis method using a release flux slope was proposed ; 2) The specific surface area of a slag particle was calculated by determining the working sphericity ; 3) The size of slag particles for the execution of the diffusion test could be as small as one to two millimeters. Results showed that the release mechanism for slag was a diffusion-controlled type ; and 4) The potential environmental impact of slag in a mortar was not significant.

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The relationship between the bulky density of MSW and its lower heating value was clarified as part of research for the establishment of the MSW feed rate stabilization system in stoker-type MSW incinerator. The compaction characteristic of MSW was also examined through experimentation with artificial MSW.
A strong correlation was admitted to exist between bulky density and the lower heating value of MSW. The presumption of the lower heating value became possible by measuring bulky density, although population and regional difference played an influential role in the bulky density concept.
There was great volume change for MSW in the feed part, and this became crucial when considering the compaction of MSW for the presumption of the MSW feed rate. The compaction characteristic curve obtained by the experiment consisted of the part expressed in the second approximation evaluation and in the first approximation equation. Though the curves depended on the composition of the MSW and/or the compaction experimental method, their shapes were basically similar.

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An efficient hand demolition system for wooden houses is proposed in this study for the effective recovery of wood materials.
The amounts of reusable wood building materials obtained from demolished wooden houses and the labor times for each demolition process were investigated. The amount of wood material (0.071 m³) recovered per unit of floor area (m²) was also obtained in this research. Demolishing a wooden house required 0.98 working hours (laborer·hours) per unit of floor area (m²) . By reducing the amount of wasted wood, the hand demolition system is very efficient from the considerations of both environment and economy.

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In order to reveal the effect of substituents for dechlorination of chloro-aromatic compounds, dechlorination reactions of mono- and di-chloro isomers of chlorobiphenyls and chlorotoluenes were carried out in a solution of NaOH in 2-propanol with a carbon-supported palladium catalyst (Pd/C) at 40°C. In the dechlorination of chlorobiphenyls, chlorine at 2 - (ortho-) position was less reactive than chlorine at 3- (meta-) and 4- (para-) positions, but chlorotoluenes exhibited no significant difference in dechlorination selectivity. The difference seems to arise from the steric effect of the substituents (phenyl and methyl) .

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