This paper analyzes the effect of industrial waste taxes on waste generation in Japan using panel data and considers the differences in the various types of taxation. The effects of economic activity on the generation of industrial waste are also analyzed. Results showed that first, taxation brings a decrease in waste generation only in the third and fourth year following the introduction of taxation, for the category of special levy by final disposal contractors. Other types of taxation, however, did not result in waste reduction. In particular, under the declaration payment by waste generators taxation system, there was an increase seen after taxation rather than any decrease. The paper also emphasizes that main economic activity have a significant correlation with waste output. Finally, this paper examines the reasons industrial waste taxation in Japan has had hardly any significant effect on waste reduction, with the exception of a few prefectures.

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The effect of reducing greenhouse gas (GHG) emissions from recycled products, a system that has been legally approved by prefectural authorities, was evaluated using a technique known as Life Cycle Assessment (LCA). Various recycled products in asphalt concrete, cement concrete, and interlocking block were evaluated based on data that was collected through a questionnaire-style survey. Results showed a clear reduction in GHG emissions for all such products. An environmental load reduction coefficient (ELRC) was defined and calculated : the amount of GHG reduction per unit of recyclable resource mixing rate for production of 1ton of the recycled product. Stock-taking of recycled products was investigated, and the amount of recyclable resources and the effect of the GHG discharge reduction were also measured. As a result of this research, it is estimated that there is a 660000ton-CO₂/year potential to reduce GHG emissions using recycled products in every prefecture throughout Japan.

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It is necessary to efficiently remove chlorine from polyvinyl chloride (PVC) and other waste plastics containing chlorine using thermal degradation liquefaction technologies for municipal waste plastics (MWP). In particular, the chlorine content of reclaimed oil products must be kept less than 100ppm due to the quality standard for pyrolysis oil in Japan. As a result, liquefaction recyclers have given up on liquefaction for MWP, because they have been unable to reduce the chlorine content. Even now, the dechlorination technology of liquefaction for MWP is an important issue for study. On the other hand, twin-screw extruders, which have been developed for dechlorination technologies used in blast furnaces and coke ovens, show shorter reaction times for dechlorination than other dechlorination technologies.
This study focused on the dechlorination ability of the screw extruder, and started with the single-screw extruder for dechlorination. The single-screw extruder was able to achieve high-efficiency dechlorination.
These technologies have been operated commercially by Sapporo Plastic Recycling Co., Ltd. since 2000.

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We compared the efficiency of capillary barriers that use several different industrial byproducts as cover sands. Unlike natural sands, such byproducts have smaller correlations between grain size distribution and drainage efficiency. On the other hand, the concentration of fluorine in cover sands that use molten slag varied as a function of the degree of compaction.
We also constructed a capillary barrier in which ferronickel slag was used as an alternative material for sand in final disposal. The environmental safety of this system was confirmed, and it succeeded in practical use.
As a result of this study, we suggest a design procedure to use alternatives to natural sands for the construction of capillary barriers.

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The recycling of food waste poses a challenge mainly due to its widespread character and the instability of its composition. In this paper, we investigate the composition of food wastes with the aim of establishing a new recycling system using the process of carbonization.
To begin, food wastes were collected from various obvious sources: manufacturers, retailers and food service businesses. The waste was then sorted into categories such as grain, vegetable, animal, bone, impure wastes and so on. The physical and chemical characteristics of these different food wastes could then be analyzed.
A large amount of moisture was found to be included in the different types of food waste. The three major components—grains, vegetables and animals—all had varying percentages of moisture depending on the seasons. However, these categories occupied 85-95% of the wet weight for the total food wastes originating from all industry types. Similarly, these components contained about 50% carbon in the dry weight. The yield of char obtained from each component through carbonization at 500 °C was about 25-30%, and fixed carbon was estimated to be 60-80%. Based on the calculations of this experiment for yield of char and fixed carbon in the air-dried char, it was estimated that there was a decrease of 30-55% in carbon release. As a result, we conclude that utilizing carbonization for the recycling of food wastes can be a useful technique for addressing various environmental issues.

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There is a wide range of stakeholders involved in the recycling system of post-consumer plastic containers and packaging : manufacturers, consumers, municipalities, recyclers and policy makers. As for some of the problems that exist within the system, challenges to specific stakeholder groups who recognize the problems may be different from challenges to those who have the potential to solve these issues. In general, methods of discussion for solving these problems, which create certain conflicts with regard to the interests of stakeholder groups, are supported by detached recommendations based on objective information. In this study, a life cycle assessment (LCA) was applied as a means of providing objective information from the viewpoint of CO₂ emission and fossil resource consumption in an attempt to develop problem-solving strategies targeted at municipalities and recyclers. Field surveys conducted with recyclers who are engaged in material recycling and feedstock recycling by liquefaction revealed problems that affected the recyclers but that were difficult to solve on their own. In light of this, recommendations for problem-solving, based on scenario assessment using LCA in addition to other aspects such as working environment and quality of recycled products, were presented to the municipalities. Some of these recommendations were rejected due to constraints imposed on the municipalities, and problem-solving strategies were further discussed.

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Utilization of food wastes as biomass is not greatly promoted. In addition to their uses as fertilizer and animal feed, food wastes are rich organic resources that can be used as bioenergy. Therefore, we thought about making charcoal from food waste available as fuel and fertilizer. In this study, food wastes were examined by thermal analyses using simultaneous thermogravimetry (TG) and differential thermal analysis (DTA). The gases produced were detected by MS and FTIR. Oxidative pyrolysis occurred in three stages of weight loss that generated two prominent exothermic peaks. Pyrolysis under oxygen-free conditions occurred in two distinct stages of weight loss that did not generate prominent exothermic peaks. The main gases produced were H₂O, CO₂ and CO, and the characteristics of the produced gas peaks were different in artificial air and oxygen-free atmospheres.

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