This paper investigates determinants for municipalities on accepting disaster wastes generated from the Great East Japan Earthquake, by using media coverage as reference and econometric analysis. Empirical results show that municipalities with higher amount of donations to the victims of disaster or higher number of volunteers are more positive about accepting of the disaster waste. In addition, it became clear that municipalities located further from the Fukushima Daiichi nuclear power plant or the municipalities with higher populations of agricultural worker are more negative toward accepting of the disaster the waste. These results suggest that there is an anxiety about the risk of radiation that prevents municipalities from accepting disaster waste from affected areas.

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To remove radioactive cesium (Cs) from sewage sludge ash, experiments were conducted on the chloride volatilization of Cs from pollucite, CsAlSi₂O₆, which may exist as a main cesium compound in such solid waste. The pollucite samples were prepared using the sol-gel method and regulated to particle sizes of 20-32 μm and 45-63 μm. They were subjected to chloride volatilization experiments, using a lab-scale electric heating apparatus, with a temperature range of 1173-1473K in a mixed N₂-Cl₂ (0.05-10 vol%) gas stream.
Results showed that the volatilization ratio of Cs from pollucite increased as the Cl₂ concentration increased up to 1 vol%. However, the ratio stayed almost the same regardless of increased Cl₂ concentrations from 1 vol% to 10 vol%. Meanwhile, the volatilization ratio of Cs increased with the heating temperature. Almost all Cs could be volatilized from pollucite within 12 h when the heating temperature was raised to above 1373 K and the Cl₂ concentration was 0.25 vol%. It was also found that the interparticle diffusion of the Cl₂ or CsCl produced did not have an influence on the volatilization rate of Cs from pollucite with particle sizes smaller than 63 μm.

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To remove ammonia from swine wastewater after primary treatment with swine manure compost-based char, adsorption experiments and removal experiments were conducted. The results of adsorption experiments showed that the Na and K cations inhibited ammonia adsorption on the biochar. The q_max parameter of the Langmuir isotherm had a strong negative correlation with the sum of Na and K concentrations. The amount of adsorption of ammonia from swine wastewater was higher than that expected from the results of an NH₄Cl solution that contained Na and K. The results of removal experiments showed that a 5% biochar addition to swine wastewater was enough to remove 130mg-N/L of ammonia, which is a target value to promote biological denitrification. This suggests that improvement of the biochar mixing method could decrease the ratio of added biochar. These results indicate that swine manure compost-based char could be utilized for ammonia removal from swine wastewater after primary treatment to promote biological denitrification.

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Decreasing the dioxin generated from combustion furnaces in waste incinerators and in other facilities that burn waste is a very important goal for society. Various technologies for decreasing dioxin in waste incinerators were investigated. However, while dioxins are collected by dust collectors, they are not removed from the dust or decomposed, so a fundamental decrease in dioxins is not achieved.
Consequently, we examined a basic technology that can resolve this problem by using low-cost ore with Mn content. The oxidation decomposition behavior of monochlorobenzene (MCB), which is known as a compound that is a precursor of dioxin, was investigated. This was evaluated using the burned product of the Mn ore, which mainly contains Mn₂O₃. In this condition, the burned product of the Mn oresuggests that it could have a decomposition effect with MCB for a long time. Moreover, reaction analysis results suggest it should not only have a role as an oxidation agent but also have an effect as a catalyst.

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Japan generates about 1 million kL of used lubricant oil annually, only 2 % of which is recycled as regenerated oil. The method presented in this report using solvent extraction with membrane separation produces few residual products : only impurities remaining in a membrane rubber bag. For this study, a continuous regeneration system was set up and operated with two waste lubricant oil samples. The oil recovery rate was estimated over time. Oil quality was tested before and after regeneration processing. Sulfur contents, carbon residue, viscosity at 40 °C, carbon number distribution, and water content were analyzed to assess the oil quality. Continuous regeneration up to 15 h was achieved. The regenerated base oil quality was confirmed, showing no degradation during 15 h extraction.

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While some of the plastic shopping bags given out to customers by shops are disposed of after a single use, others are reused as trash bags in municipalities where designated trash bags have not been introduced. In addition, discontinuation of plastic shopping bags has an influence on recycling of plastic containers and packaging in municipalities where recycling collection of plastics waste is implemented. The effect of stopping distribution of plastic shopping bags by retailers also depends on how waste management policies are implemented in the municipalities where retailers are located. This paper presents how stopping distribution of plastic shopping bags at shops can effect greenhouse gas reduction, evaluated using life cycle assessment that looks at differences in the indirect effects of municipal waste management policies. Results showed that regardless of the municipality, there were almost similar effects, when stopping distribution of plastic shopping bags was assumed to influence on only their life cycles. The effects were shown to be less in municipalities where plastic shopping bags had been reused or recycled, when stopping distribution of plastic shopping bags was assumed to influence on not only their life cycles but also that of other products as well.

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The conversion of biomass waste containing cellulose to fuel or chemical raw materials is desirable. Therefore, we sought to hydrolyze cotton waste, which is mainly composed of cellulose, to produce glucose. Then, this glucose was fermented to produce lactic acid, which is a raw material for bioplastics as polylactic acid. In addition, the lactic acid was used as a catalyst to promote the hydrolysis of cotton and to reduce the catalyst separation costs. For this paper, we investigated the optimum reaction conditions and reactor selection in order to promote the hydrolysis of cotton while suppressing excessive degradation of the glucose. The results suggest that high reaction temperature and long retention time are effective to promote the hydrolysis of cotton. However, low temperature and short retention time are effective to suppress excessive degradation of the glucose. This confirmed that a semi-flow reactor, which can discharge solution that contains glucose at any time, should be adopted to promote cotton hydrolysis while suppressing excessive glucose degradation.

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Crude glycerol, a byproduct of biodiesel fuel, BDF, was treated simply using dilution and neutralization. Then it was kept statically to separate an upper layer of oil from a lower layer of glycerol solution. The two layers were collected separately and were examined following recycle usage : the oil and the glycerol solution were used respectively as a fuel and denitrification reagent. Results obtained from laboratory experiments demonstrated that the oil contained small amounts of ash and water. The caloric content was almost equal to that of virgin edible oil. The denitrification efficiency and the biodegradability of the glycerol solution examined in the activated sludge of excreta treatment were almost equal to those of a 50 % methanol solution. Moreover, the glycerol solution, which was produced in a two cubic meter vessel assembled in an actual scale refining apparatus that showed identical results to those obtained from laboratory experiments, was available for use at an excreta treatment facility as a denitrification reagent.

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Versatile models that improve upon management of collection and transport of urban solid waste in developing countries are not often actualized due to the varied complex social situations at play. Meanwhile, an international cooperation project, known as The Project for Strengthening Solid Waste Management in Dhaka City, has invented a collection and transport improvement method called WBA (Ward-Based Approach). The project has been highly evaluated. The authors of this paper has conducted a field work on this project, found that the method was an approach integrated major components of collection and transport, and thus achieved the localization of them. Based on these findings, the authors present in this paper a conceptual model for improved management of collection and transport of urban solid waste in developing countries.

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WtE (Waste to Energy) plants contribute to the realization of a low-carbon society. Therefore, promotion of high-efficiency WtE power generation plants is expected in Japan. However, WtE plants have severe problems with the corrosion of boiler tubes, especially super-heater tubes. For this reason, the steam conditions of WtE boiler plants have been limited to 4 MPa and 400 °C.
It is very important to understand the high-temperature corrosion characteristics of super-heater tubes in actual WtE plants in order to design boilers that can have higher temperature steam conditions compared to current plants.
We developed a new tool for measuring the corrosion rate in a short period of time compared to conventional methods. Using this tool, we have measured many corrosion rates of SUS310J1 stainless steel in WtE plants with stoker type waste incinerators. SUS310J1 has been widely used as a high-temperature corrosion-resistant material for super-heater tubes in Japan.
Through this research, we found that the corrosion rate of SUS310J1 at gas temperatures below 550 °C and metal temperatures from 350 °C to 450 °C reaches a maximum at a metal temperature of around 400 °C after which it stays nearly constant. At higher gas and metal temperatures, however, the corrosion rate increases rapidly.

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At the Tono municipal waste incinerator, they burned grass that had been contaminated by radionuclides from the Fukushima Daiichi nuclear power plants with ordinary wastes. We analyzed the income and outcome balance of radioactive cesium using data of the incinerator. We obtained data of 394 days between November 2012 and July 2014 from Tono city. Selecting appropriate data of 274 days, Bayesian regression analysis revealed that the recovered proportion of radioactive cesium from ash was 64.7 % (95 % credible interval : 56.9-72.6). Allowing for the radioactive cesium that was lost by absorption or adhesion to the equipment, one can conclude that the bag filter collected 64.6 % of radioactive cesium from the flue gas. The ¹³⁷Cs concentration in the stack gas was estimated at up to about 1.4 Bq/m³N, which cannot be detected using current administrative methods. Scientific requirements for radioactive waste incineration should include a balance investigation of radionuclides and convincing analytical methods of radionuclide concentrations in the waste gas.

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An experimental gas-liquid equilibrium equation was obtained by measuring the polychlorinated biphenyl (PCB) concentration in gas that was in equilibrium with five insulating oil samples. The PCB concentration in the gas was calculated from the PCB adsorption amount of the activated carbon used in the exhaust-gas treatment of two large tanks for 533 days. Furthermore, a predictive equation of the PCB concentration in a handling room was determined from the volatilization rate of PCB and the ventilation air volume. Then, the indoor average concentration of PCB was calculated from the PCB adsorption amounts of the activated carbon used for 365-612 days in the air purification of five handling rooms where electrical equipment contaminated with trace amounts of PCB was stored, dismantled or had oil removed. Consequently, the indoor concentrations were 1/910,000-1/21,000 of the limit for workrooms and 1/45,000-1/1,100 of the provisional limit for the atmosphere. These findings suggest that the handling of electrical equipment contaminated with trace amounts of PCB in a properly ventilated room is sufficiently safe even without purifying the room air with activated carbon or using a gas mask.

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Industrial waste with silica components is anticipated as an alternative resource for silica stone, which is the main material for Autoclaved Lightweight Concrete (ALC) Panels. Using cements and silica stone powder as main raw materials, ALC panels can be produced to have heat resistance and long-term stability because of their tobermorite crystalline contents. Tobermorite generation requires hydrothermal synthesis under saturated steam pressure at 180 °C. This study assessed glass waste availability as an alternative resource for silica stone. Candidates were tiles and pot shard waste, liquid crystal glass, and glass bottles. Considering the influence on hydration products, these were evaluated using X-ray powder diffraction (XRD) analysis. Results show that the optimum replacement of silica stone powder with tiles and pot shards waste was approximately 25 % to produce tobermorite formation and dense structure. Calculating the demand of alternative resources and the supply of tiles and pot shard waste, results suggest that the 80 % of its annual emissions are useful.

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Clarifying the quantitative impacts of leachate on the surrounding environment for each landfill type is important. Large-scale lysimeters were prepared with controlled waste samples that included large amounts of organic waste. Experimental data from each landfill type were considered and compared in order to construct an estimation model for dissoluble carbon. During the liquefaction process of waste decomposition, the same value of dissoluble carbon was observed in each landfill type. Therefore, landfill types did not influence the dissolution rate of carbon. Moreover, the most important factor in our estimation proved to be the cumulative amount of leachate per unit volume of landfill waste. Finally, an estimation model for the dissolved carbon of leachate from semi-aerobic landfill was constructed with a logarithmic curve using an approximation equation. The applicability of this model was proven by the results of a comparison between the estimation data and the analyzed data.

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Material and energy balance in a dry methane fermentation facility were estimated using data from four years of operation. Input waste was source-separated food waste and waste paper from households and commercial sectors. Residents were asked to separate their food waste in biogas-collection bags prior to disposing. Based on a composition analysis, the rate of separation into biogas-bags was estimated to be 78.6 % for food waste and 45.6 % for waste paper. Participation rate of residents in this project was estimated to be 65.3 %. An analysis of weekly data shows that the biodegradation rate for the food waste is slightly higher than that of the waste paper. In this facility, waste is being heated by injecting steam into recirculated sludge. Heat loss was found to be very small in the summer time, and average loss in the first two years accounted for 40 % the heat provided by steam input.

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The production of playground equipment made from bamboo with blast-furnace slag was investigated. VOC-free bamboo board made from two unused materials was produced and some evaluation tests were performed. The blast-furnace slag was selected as an inorganic adhesive for the production of the board in order to make it VOC-free. The optimum conditions for the small boards were 160 °C solidification temperature and 3.0 MPa solidification pressure when the boards were produced under the conditions of commercial boards. The 14.5 MPa bending strength and 1.15 apparent density for the board at the optimum conditions were properties similar to those of commercial boards. The adhesive properties of the slag were confirmed by SEM observation. The linkage among the slag particles occurred easily and inorganic adhesives permeated the texture of the bamboo. Finally, 70cm square boards were manufactured in order to make playground equipment. A jungle gym was successfully manufactured using ordinary wood processing machines. In the future, VOC-free bamboo board could be used practically.

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A material flow analysis (MFA) study was conducted on all materials (including ferrous and non-ferrous), parts, equipment and consumables extracted from the ship breaking industry in Chittagong, Bangladesh. In fiscal year 2010, a total of 100 large vessels (1.35 million LDT) were dismantled. From this, 1.17 million tons of steel and ferrous materials along with 0.1 million tons of machines, equipment, hardware and fittings were collected. Out of this, about 89 % is being reused or recycled, while reuse by basic segregation, processing and repair accounts for about 22 %. Above all, “Ship to Ship” reuse by the shipbuilding and shipping industries accounts for about 8 %. Although a field survey observed insufficient control of hazardous materials, the situation has been slightly improved due to the expected enforcement of the ship recycling treaty in the future. In addition, the paper examines characteristics of ship breaking in developed and developing countries using a comparative study with a ship breaking pilot project in Muroran, Japan in 2010.

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The Ministry of Environment Notification has defined no analytical method for recycled material resources. However, because an appropriate resource evaluation system is necessary, we compared the contents of WEEE and molten metal found using several methods. The methods included matte fusion, which is used for the evaluation of resources in the field of nonferrous metal smelting, and chemical analysis using test methods outlined in Notification No.19 of the Ministry of the Environment, provisional analytical methods for precious and rare metals in electric and electronic products (“provisional analysis method”). The content values obtained using the test methods in Notification No.19 were lower than those obtained using the other method, but the provisional analysis method seems to be suitable for use as a screening test. Although the reproducibility of analysis using the provisional analysis method was lower than that of the matte fusion method, both methods provided comparable content values. Matte fusion is difficult to implement except by the refining industry. For various and diverse metals, provisional analysis is useful by environmental laboratories operated by local governments. Therefore, the provisional analysis method is expected to be used by local governments for analyses conducted in the resource recycling field.

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Supplies of phosphorus are strongly dependent on imports from China and Morocco. Therefore, development of recycling techniques for phosphorus from industrial waste materials is an important objective for future resource security and supply stability. This study investigated the possibility of recycling phosphorus from waste chemical conversion treatment sludge to produce positive electrodes of lithium-ion secondary batteries. Lithium iron phosphate (LiFePO₄) was synthesized using phosphorus and iron contents of waste sludge. The crystal structure and electrode properties of the synthesized LiFePO₄ were evaluated. Results show that LiFePO₄, which is rechargeable, was synthesized from waste sludge. The positive electrode produced from synthesized LiFePO₄ exhibited excellent cyclic performance, although the charge-discharge capacity decreased concomitantly with increasing amounts of sludge. The positive electrode containing 25 % waste sludge as a source of phosphate retained more than 140 mAh g⁻¹ of discharge capacity, which is comparable to commercially used batteries. Results of this work demonstrate the possibility of recycling waste chemical conversion treatment sludge to produce positive electrode materials for lithium-ion secondary batteries.

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Most bio-waste contains a high amount of moisture, but has high caloric value if dried. Effective drying could produce solid fuel from bio-waste. This paper discusses the effectiveness of drying with aerobic microbiological degradation similar to a composting process. Wood chips (WC) that show little bio-degradation and a mixture of WC and dogfood (Mix) that shows bio-degradation were used as experimental materials. Each of them was placed in a plastic column and aerated. During each experiment, changes in temperature, moisture and dry mass were monitored. The results showed that the moisture evaporation from Mix was greater than that from WC because of the increased temperature that resulted from biodegradation. We also clarified that the heat generation from biodegradation was greater than the heat used for moisture evaporation, material temperature increase and aeration. This indicates that effective drying can be achieved by utilizing the heat generated from biodegradation.

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In spite of being a huge metropolis with a population of more than three million, Surabaya in the Republic of Indonesia has drastically reduced its landfill disposal over a period of five years, transforming itself into a green city. The driving force behind this achievement is the Takakura Composting Method, which was acquired in Surabaya in cooperation with Kitakyushu. This paper investigates the role and effects of this technology through a field study conducted in Surabaya. The Takakura Composting Method was set up as a technology that inspires satisfaction amongst the various stakeholders because of its effective administrative policies and the way in which it inspires inhabitants to become active about the issue of garbage composting. Although the contribution ratio for reduction of landfill disposal against garbage recycling for the program was restrictive—at approximately 19.9 %—it has promoted the collection of recyclable waste within the community and spilled over into development of a compost center by the administration. Since 2011, the city has been able to reduce its landfill disposal rate by more than 60 % per capita GRP. Moreover, with the aim or reaching a 30 % green goal, composting of organic waste is being vigorously promoted, there have been reports that as the program continues, the amount of waste can be stabilized at an all-time low level in the foreseeable future.

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The purpose of this research was to produce an amino acid-rich food resource from marine waste such as the scallop mantle by using an enzyme agent treatment. From the analysis of the protein content, it was observed that this raw material could be effectively used as a protein resource. The measurement of harmful heavy metal indicated that the raw material was safe as food. The solubilization rate of the mantle markedly increased due to the effect of enzyme agent treatment. HPLC was carried out to obtain basic palatability characteristics for the scallop mantle extract. The free amino acid content of the extract was quadrupled by enzyme agent treatment. Due to its high amino acid content and infinitesimal amount of harmful heavy metal, the extract is promising as a food resource.

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