This study was intended to predict effects on citizens'participation rates in recycling programs according to administrative actions such as promoting environmental consciousness, providing information, and changing of collection service.
Questionnaires designed to measure factors that are relevant to recycling behavior were sent to residents of Itabashi Ward, Tokyo. The authors developed logistic regression models for predicting recycling behaviors of: “Curbside Collection of Cans and Bottles”, “Drop-off Collection of Paper Packages”, and“Drop-off Collection of PET Bottles”. We selected predictors for recycling behaviors on three collection programs as: “Perception of Information”, “Evaluation of Trouble”, and“Perception of Coping Efficacy”.
The authors also conducted sensitivity analyses of the developed models. Participation rates were calculated for three conditions: “Maximization of Perception of Information”, “Minimization of Evaluation of Trouble”, and“Maximization of Perception of Coping Efficacy”. Results suggested that“Maximization of Perception of Information”had the greatest effect, followed by“Minimization of Evaluation of Trouble”, and“Maximization of Perception of Coping Efficacy”.
In addition, the authors suggested policy prescriptions for improving citizens'participation rates through analyses of the current status of citizens'utilization of PR media of the municipality and through analyses of the relationships between“Evaluation of Trouble”and relevant factors.

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We focused on separating fly ash by particle size in order obtain fractions with different compositions. We then conducted heating experiments on each fraction under a variety of temperature and atmospheric conditions in order to understand the re-synthesis mechanisms of chlorinated aromatics in fly ash and the distributions of PCBs and chlorobenzenes (CBzs) by fly ash particle size. As a result, we found that the contributions of metal catalysts and unburned carbon in the formation of PCBs and CBzs were dependent on heating temperature. The homologue patterns of PCBs and CBzs were almost the same in all fractions of fly ash in the heating experiments. This indicates that all fractions of fly ash had the same formation patterns. The effect of atmosphere on the formation of chlorinated aromatics showed no difference among the fractions. HCl in a nitrogen atmosphere with 10% oxygen did not promote generation of PCBs and CBzs in fly ash. We confirmed that metal chlorides in fly ash were important as a chlorine source rather than HCl gas for the formation of chlorinated aromatics in fly ash.

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The vaporization and diffusion of volatile chlorinated organic solvents, such as tetrachloroethylene and trichloroethylene, in contaminated soil were analyzed to predict the expansion of contamination and to clean them up more effectively. The vaporization rate of PCE liquid in soil was very high. The gas concentration reached saturated vapor pressure within 1.1 seconds of contact time. Therefore, it was shown that, if there are liquid chlorinated organic solvents in soil, strainers must be located to the liquid depth with high flow rate to clean them up effectively. The effective diffusion coefficients in soil were about 0.17 times that of the molecular diffusion coefficients, and the tortuosity factors were 1.8-2.5.

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To clarify the behavior of low-boiling-point heavy metals in the melting process of wastes, the suitability of simulations using thermodynamic models was investigated by comparing the results of simulations with those of actual operations undertaken in an incineration-residue melting furnace in a test plant.
Results of the simulations indicate that melting conditions such as melting temperature and oxygen partial pressure greatly affect the behavior of low-boiling-point heavy metals in the melting process. In particular, we obtained data on the behavior of Pb because its presence can cause environmental problems when molten slag is utilized.
As melting temperature increased and oxygen partial pressure decreased, the volatilization of Pb increased and the content of Pb in the molten slag became lower. In addition, the actual operations of a test plant confirmed that most Pb volatilizes into gas and the Pb content of molten slag is kept as low as 60-70 mg/kg. These results confirm the accuracy of the simulation test.

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Many kinds of processes for the removal and decomposition for trichloroethylene (TCE) have been investigated. The solvothermal process using methanol and sodium hydroxide (alkaline methanol solvent) has been developed and compared with ordinary alkaline hydrothermal conditions for dechlorination of TCE.
Even under alkaline hydrothermal condition using water as a solvent, perfect dechlorination of TCE (initial concentration up to 42, 000 mg/L) is achieved at a reaction temperature of 523 K and a few minutes of reaction time if the ratio of used NaOH to required NaOH is greater than 2.0. However, polymers are formed as byproducts and secondary disposal of solvents is required, because whole dissociated chloride ions are dissolved in the solvent. In contrast, we found that dechlorination of TCE (initial concentration 82, 000 mg/L) is possible with a reaction temperature of 523 K and a reaction time of 15 minutes by using thermal alkaline methanol solvent. Furthermore, the solvent (methanol) can be reused easily after the separation of sodium salts, because the dissociated chloride precipitates with salts and are not dissolved in methanol. Therefore, the dechlorination process of TCE can be made simpler and the secondary disposal of wastewater is not required.

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Waste treatment creates relations of interdependence between waste treatment sections and production sections. The Waste Input-Output table (WIO) analyzes the relations of such interdependence. Considering the product goods from the construction industry, there is a time lag between production and disposal. However, a static model like WIO is unsuitable for the analysis of durables with several years of life. The purpose of this study is to dynamically extend Waste Input-Output Analysis.

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Thermophilic methane fermentation at 55°C was applied to garbage treatment. Continuous feed-and-draw operation was conducted in a complete-mixing type reactor with artificially prepared garbage. Based on calculations of COD, more than 80% of the garbage was transformed to methane, with 0.4 to 0.5 L of methane gas being produced from 1 g VS of garbage. Inhibition of methanogenesis by ammonium nitrogen was initiated when its concentration exceeded 2, 000 mgN/L. Total nitrogen concentration in the garbage treated should be less than 4, 000 mgN/L, as about half of the total nitrogen was transformed to ammonium nitrogen by anaerobic methane production processes.

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Actual conditions of environmental balance (input and output) of an office, which was regarded as having no strong environmental consciousness, were measured continuously over a period of eight years (1995-2002) . Following field measurements, we analyzed and clarified effects of some behavioral analysis methods, such as prompting and feedback, on behavioral changes of office members to environmentally conscious actions. By installment of boxes for paper that was printed on a single side, much was used. Nevertheless, recycled paper was seldom purchased. Furthermore, waste paper was seldom classified and was not thought of as a recoverable resource. Instead, it was cast away as a combustible. Effects of installing the boxes for half-used paper on behavioral changes of office members to use single-sided paper disappeared over three years because of the change in office members and the office arrangement. The method of real time feedback together with detailed instructions on environmentally concerned actions caused behavioral changes in use of copy machines, printers, and desktop computers, thereby reducing electricity consumption. On the other hand, the electricity that was consumed by laptop computers increased. Consequently, our findings showed the following tendency: it is easier to reduce electricity consumption by changing the methods of use of infrequently used business machines, such as copy machines, printers and desktop computers than those of frequently used equipment, such as laptop computers.

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The present study explored the effects of commitment to volunteer environmental activities on empowerment and intention to participate in further volunteer activities. A survey of 378 volunteer members was conducted in two cities in which the municipal administrations had introduced a new recycling system. Main results of the survey were the following. The commitment enhanced both individual empowerment and collective empowerment. The effect of commitment to volunteer activities on intention was mediated by the acquired empowerment. Collective empowerment (efficacy to community change) and individual empowerment (solidarity) were the main determinants of their intention to participate in further voluntary activities.

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Residential waste was carbonized as a means of fuel production, metal recovery, and pretreatment for landfill. Tested materials were combustible waste, incombustible waste and bulky waste, which were collected from a residential area and a shredding facility.
Char product from bulky waste showed good quality for fuel due to high wood content and potential recovery of metal such as Cu. The quality of char from the other two types of waste was low, but the leaching of heavy metal was minimized and organic contents were reduced, showing its effectiveness as a pretreatment for landfill disposal. Washing treatment could also reduce chlorine contents enough for fuel use. Though both screening after ball milling and density separation were effective in reducing ash contents, the former was more practical because of its simple process.

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Since the full implementation of the Law for Promotion of Sorted Collection and Recycling of Containers and Packaging (The Containers and Packaging Recycling Law) in 2000, numerous local governments have introduced a separate collection system for plastic containers and packaging other than PET bottles. We have gathered information from these localities to grasp the per-capita amounts and composition of separate collection regimes. Then, we analyzed their differences resulting from various collection methods and other factors.
Per-capita amounts of the separate collections are greater in cases where the collection scheme is applied to the whole administrative area, in contrast to where it is carried out in limited “model areas”. This tendency is probably attributable to limited awareness-raising methods associated with model area applications.
Results of household-waste compositional analyses in Neyagawa-city provide supporting evidence for that conjecture: when the model area scheme was extended to the whole area, residents' cooperation increased. Consequently, more than 70% of plastic bottles, packs and trays were separated appropriately for collection.

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Refuse derived fuel (RDF), as a carbonaceous material, was made to react isothermally with sub-supercritical water (400-650°C, 200-300 atm) and a CO₂ fixation reagent, Ca (OH) ₂, inside a closed metallic tube reactor (7cm³) . The product gas consisted of hydrogen and a little methane gas. Addition of catalysis NaOH or KOH increased the production of gas. KOH was 2.4 times more effective in producing gas than NaOH. X-ray diffraction revealed that Ca (OH) ₂ and CaCO₃ existed mainly in residues after reaction tests with a CO₂ fixation reagent, Ca (OH) ₂ or CaO. Therefore, it is supposed that the overall reaction took place according to the chemical reaction below. Steelmaking slag for CO₂ fixation provided maximum gas generation of 1.27 times as much as molar carbon in an RDF sample with KOH.
C+H₂O+Ca (OH) ₂=CaCO₃+2H₂

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Catalytic dechlorination of 4-chlorobiphenyl (4-CBp) and chlorobenzene (CBz) was carried out at 35°C in a solution of NaOH in 2-propanol in the presence of a supported palladium catalyst (Pd/C or Pd/Al₂O₃) . In the individual substrate reaction, the initial dechlorination rate of CBz was much faster than that of 4-CBp by a factor of 3.4. When they were mixed, the dechlorination rate of CBz was suppressed and was slower than that of 4-CBp. Since 4-CBp preferably adsorbs on the catalyst in the presence of CBz, the adsorption abilities of substrates seem to affect the reaction rate in the competitive reaction.

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The adsorption characteristics of volatile chlorinated organic compounds in soil must be clarified to understand the extent of contamination and to determine effective cleanup conditions for soil vapor extraction. In this study, an adsorption equilibrium model for soil with any water content and an estimation method for adsorbed amounts were developed. This model was developed with consideration of the different adsorption rates of dry and wet pores, the adsorption to organic soil matter and the dissolution in water. The adsorption equilibrium relation of every kind of soil and every substance can be expressed well using the dry pore adsorption ratio γ. γ can also be expressed related to the water content. The predicted amounts agreed well with the measured data.

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