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To clarify current collection rules of waste batteries in municipal waste management in Japan and to examine future challenges for hazardous substance control and safety, we reviewed collection rules of waste batteries in the Tokyo Metropolitan Area. We also conducted a field survey of waste batteries collected at various battery and small waste electric and electronic equipment (WEEE) collection sites in Tokyo. The different types of batteries are not collected in a uniform way in the Tokyo area, so consumers need to pay attention to the specific collection rules for each type of battery in each municipality. In areas where small WEEE recycling schemes are being operated after the enforcement of the Act on Promotion of Recycling of Small Waste Electrical and Electronic Equipment in Japan in 2013, consumers may be confused about the need for separating batteries from small WEEE (especially mobile phones). Our field survey of collected waste batteries indicated that 6–10% of zinc carbon and alkaline batteries discarded in Japan currently could be regarded as containing mercury. More than 26% of zinc carbon dry batteries currently being discarded may have a lead content above the labelling threshold of the EU Batteries Directive (2006/66/EC). In terms of safety, despite announcements by producers and municipalities about using insulation (tape) on waste batteries to prevent fires, only 2.0% of discarded cylindrical dry batteries were insulated. Our field study of small WEEE showed that batteries made up an average of 4.6% of the total collected small WEEE on a weight basis. Exchangeable batteries were used in almost all of mobile phones, digital cameras, radios, and remote controls, but the removal rate was as low as 22% for mobile phones. Given the safety issues and the rapid changes occurring with mobile phones or other types of small WEEE, discussion is needed among stakeholders to determine how to safely collect and recycle WEEE and waste batteries. [ABSTRACT FROM AUTHOR]

Abstract: Waste electrical and electronic equipment (WEEE) has received extensive attention as a secondary source of metals. Because WEEE also contains toxic substances such as heavy metals, appropriate management of these substances is important in the recycling and treatment of WEEE. As a basis for discussion toward better management of WEEE, this study characterizes various types of WEEE in terms of toxic metal contents. The fate of various metals contained in WEEE, including toxic metals, was also investigated in actual waste treatment processes. Cathode-ray tube televisions showed the highest concentration and the largest total amount of toxic metals such as Ba, Pb, and Sb, so appropriate recycling and disposal of these televisions would greatly contribute to better management of toxic metals in WEEE. A future challenge is the management of toxic metals in mid-sized items such as audio/visual and ICT equipment because even though the concentrations were not high in these items, the total amount of toxic metals contained in them is not negligible. In the case of Japan, such mid-sized WEEE items as well as small electronic items are subject to municipal solid waste treatment. A case study showed that a landfill was the main destination of toxic metals contained in those items in the current treatment systems. The case study also showed that changes in the flows of toxic metals will occur when treatment processes are modified to emphasize resource recovery. Because the flow changes might lead to an increase in the amount of toxic metals released to the environment, the flows of toxic metals and the materials targeted for resource recovery should be considered simultaneously. [Copyright &y& Elsevier]

Abstract: We estimated the amount of waste electrical and electronic equipment (WEEE) generated in South Korea by using the population balance model (PBM) based on a lifespan distribution analysis. This is the first study to apply PBM to estimate WEEE generation in South Korea. The lifespan distribution analysis of electrical and electronic equipment (EEE) was based on the results of a questionnaire survey of 1000 households, which were analyzed with the Weibull distribution. As a result, we could estimate the domestic service lifespan and lifespan distribution shape parameter for eight selected products. Using the lifespan distribution analysis and other data, such as the shipment volume and the number of products owned by households, we estimated the amount of WEEE generated for the eight selected items from 2000 to 2020. We found that 1.2million air conditioners, 2.5million televisions, 1.3million microwave ovens, 1.2million kimchi refrigerators, 17.0million mobile phones, 1.7million refrigerators, 2.0million vacuum cleaners, and 1.4million washing machines were generated as WEEE in 2010. We also compared our WEEE estimates with the number of items collected through the official WEEE recycling program from 2003 to 2009 and found that in 2009 washing machines had the highest collection rate (28%) and air conditioners had the lowest rate (7%). [Copyright &y& Elsevier]

Heavy metals like mercury that are emitted into the environment remain there indefinitely, posing a long-term threat to both the environment and human health. Elemental mercury is volatile and is in gaseous form, and because of the long residence time, transported over long distances. Comprehensive control of mercury emissions therefore remains an important international issue. The crucial steps for designing effective approaches for such control include the quantification of mercury emissions by sources and the identification of geographical characteristics of the emissions. In this study a detailed, high-resolution inventory of Japanese mercury emissions in 2005 was developed to improve understanding of their geographical distribution. Proceeding from a national emissions inventory per source category, emissions were spatially allocated with increasing geographical resolution in a stepwise procedure using statistics from geographic information resources, yielding mercury emissions per prefecture, per municipality and per grid cell of approximately 1 × 1 km. The five prefectures with the highest emissions were Fukuoka, Yamaguchi, Hyogo, Oita, and Hokkaido, accounting for 35.2% of all emissions. In each prefecture a small number of municipalities account for a major share of emissions. Distribution by grid cell is characterized by a concentration of 50% of all emissions in a mere 32 of the 255 954 grid cells over which emissions are distributed in this study. It was also quantitatively confirmed that use of larger grid cells leads to greater uncertainty in emissions distribution. Problems with data collection are clarified and measures to improve the accuracy of future estimation are proposed. [ABSTRACT FROM AUTHOR]

Abstract: In Japan, waste electrical and electronic equipment (WEEE) that is not covered by the recycling laws are treated as municipal solid waste. A part of common metals are recovered during the treatment; however, other metals are rarely recovered and their destinations are not clear. This study investigated the distribution ratios and substance flows of 55 metals contained in WEEE during municipal waste treatment using shredding and separation techniques at a Japanese municipal waste treatment plant. The results revealed that more than half of Cu and most of Al contained in WEEE end up in landfills or dissipate under the current municipal waste treatment system. Among the other metals contained in WEEE, at least 70% of the mass was distributed to the small-grain fraction through the shredding and separation and is to be landfilled. Most kinds of metals were concentrated several fold in the small-grain fraction through the process and therefore the small-grain fraction may be a next target for recovery of metals in terms of both metal content and amount. Separate collection and pre-sorting of small digital products can work as effective way for reducing precious metals and less common metals to be landfilled to some extent; however, much of the total masses of those metals would still end up in landfills and it is also important to consider how to recover and utilize metals contained in other WEEE such as audio/video equipment. [Copyright &y& Elsevier]

Abstract: End-of-life electrical and electronic equipment (EEE) has recently received attention as a secondary source of metals. This study examined characteristics of end-of-life EEE as secondary metal resources to consider efficient collection and metal recovery systems according to the specific metals and types of EEE. We constructed an analogy between natural resource development and metal recovery from end-of-life EEE and found that metal content and total annual amount of metal contained in each type of end-of-life EEE should be considered in secondary resource development, as well as the collectability of the end-of-life products. We then categorized 21 EEE types into five groups and discussed their potential as secondary metal resources. Refrigerators, washing machines, air conditioners, and CRT TVs were evaluated as the most important sources of common metals, and personal computers, mobile phones, and video games were evaluated as the most important sources of precious metals. Several types of small digital equipment were also identified as important sources of precious metals; however, mid-size information and communication technology (ICT) equipment (e.g., printers and fax machines) and audio/video equipment were shown to be more important as a source of a variety of less common metals. The physical collectability of each type of EEE was roughly characterized by unit size and number of end-of-life products generated annually. Current collection systems in Japan were examined and potentially appropriate collection methods were suggested for equipment types that currently have no specific collection systems in Japan, particularly for video games, notebook computers, and mid-size ICT and audio/video equipment. [Copyright &y& Elsevier]

We conducted a decomposition analysis of material flows in a dynamic system, focusing on factors in the generation of waste consumer durables. A methodology for the analysis of consumer durables was developed and applied to three common consumer durables: cathode ray tube TVs, refrigerators, and passenger cars. The methodology decomposed changes in the numbers of waste products into three factors: changes in lifespan distribution, past trends in replacement sales, and past trends in sales for additional purchases. The decomposed equation clearly showed that the number of waste products would not necessarily be reduced by lifespan extension alone. This is because the number of waste products generated is affected not only by current lifespan distribution but also by past trends in sales for replacement and in additional purchases. The results show that changes in past replacement sales influence the current generation of waste, even if current replacement sales are declining. To reduce the generation of waste products on a short-term basis, lifespan must be extended until the waste-reducing effect of lifespan extension exceeds the waste-increasing effect of the other two factors. From a long-term perspective, controlling current replacement and additional purchases can be used to prevent future waste product generation. [ABSTRACT FROM AUTHOR]

Lifespan is an essential parameter for the accounting and analysis of material stocks and flows, one of the main research topics in industrial ecology. Lifespan is also important as a parameter that portrays the current and historical situation of industrial metabolism, which is an area of interest to industrial ecologists. In the present article, the available information from various reports on product lifespan was reviewed. Although we found a large number of data for many durables, the definition of lifespan in published articles varied, which limited our ability to compare reported values. We therefore first defined lifespan and then compared the international and historical data. We compiled more than 1,300 data sets from various sources and identified some differences among the types of goods and among regions. With the reviewed data noted in this article, we established a database, named LiVES (Lifespan Database for Vehicles, Equipment, and Structures), and will disclose it on the Internet to share the information. [ABSTRACT FROM AUTHOR]

Lifespan of commodities is essential information for material flow analysis and material stock accounting. Lifespan data is available in the literature; however, it varies in definition and in methodology employed. This article reviews and categorizes different types of lifespan distribution and distribution estimation methodologies, and investigates the relationship and differences between lifespan definitions and estimation methodologies. Lifespan distribution of commodities can be classified into five types from two perspectives: base year for which the distribution is drawn, and vertical axis of the distribution. The methodologies for estimating lifespan distribution were classified into four types and the details of each methodology and the relationship to the definition of lifespan were also clarified. This article also examines differences in actual lifespan data—between the types of distribution, the definitions, and the employed methodologies—by comparing reported data in literature. Any of the four methodologies are theoretically applicable and provide the same value of a lifespan; however unless accurate data such as census statistics are available, lifespan data can vary, and therefore we must be very cautious about the representativeness of sample data. [ABSTRACT FROM AUTHOR]

Various toxic, useful, and/or scarce metals in waste electric and electronic equipment (WEEE) have rarely been assessed due to low data availability, except for the four metals regulated by the European Union's Directive on the Restriction of Hazardous Substances (RoHS). This article describes the results of screening 36 metals in WEEE using simple assessment methods for cases where the decision makers do not know for which substances in a product countermeasures should be taken and where data cannot be easily obtained. First, this study examines the decision-making process and prerequisites for screening, classifies existing assessment methods, and presents three simple indices for screening (resource consumption, water pollution affecting human health, and aquatic biota conservation) so that screening can be readily started for many (20-36) metals. Following this, a case study is conducted for waste TV sets, revealing which metal in which product module or component should be targeted by environmental countermeasures. Finally, the screening results are compared with those of six other methods using diagrams devised to indicate the superiority of screening methods, and several screening techniques are discussed. The conclusions are that the EU RoHS Directive does not necessarily cover all of the toxic metals that could be of concern and the screening methods presented could help identify such metals; the selection of methods is critical; and a more detailed method does not necessarily provide more accurate results. [ABSTRACT FROM AUTHOR]

In order to control microphase separation of polystyrene-silica nanocomposites, perhydropolysilazane (PHPS), which is a preceramic of silica, and epoxidized poly(styrene-block-butadiene-block-styrene) triblock copolymer [E-SBS,Mw= 8.0 × 104, styrene: 40 mol%, degree of epoxidization of butadiene: 20 mol%] or poly(styrene-block-butadiene-block-styrene) triblock copolymer [SBS,Mw= 1.40 × 105, styrene: 30 mol%] as templates of microphase separation were blended, following the calcination of composites in steam at 60°C. Well-arranged microphase separation was formed with E-SBS, though the macrophase separation was formed with SBS. The morphology of the microphase separation of the composites with E-SBS and PHPS was widely controlled by varying the PHPS content based on Molau's law. Silica domains were formed in polybutadiene domains. NMR analysis indicated the interaction between silanyl group of PHPS and epoxy group in E-SBS. The composites on the substrate were highly transparent and the surface of the composite with 73.5 vol% of silica was harder than 4H. [ABSTRACT FROM PUBLISHER]

Abstract Product replacement programs promote the replacement of durable goods such as automobiles, home appliances and houses with new energy-efficient products using financial incentives such as subsidies. Many countries have implemented such programs to reduce environmental loads. These programs affect the point in time at which the decision to replace a product is made (and acted on) by consumers, which, in turn, influences the overall effectiveness of the program. Thus, in order to improve the policy design of these replacement programs, it is necessary to consider the mechanism of the consumer product replacement decision. This study examines the effects of the Japanese Home Appliance Eco-Point Program on the timing of household air conditioner replacements and the resulting GHG emission reduction effects and assesses the program's cost-effectiveness using a dynamic discrete choice model and an input–output model. We found that the program increased the air conditioner replacement rate by 1.5%–1.9% and reduced GHG emissions by 28,516 tCO 2 eq. However, the cost per ton of CO 2 eq reduced was approximately 978 US dollars, which is quite high compared to the GHG emission reduction costs of other programs. We conclude that the Home Appliance Eco-Point Program as constituted in 2009–2010 was not a cost-effective means to reduce GHG emissions and that appropriate policy coordination needs to be conducted in order to improve the cost-effectiveness of such programs in the future. [ABSTRACT FROM AUTHOR]

An ion chromatography with post-column derivatization with 1,5-diphenylcarbazide (IC-DPC) analytical method was modified to enable measurement of trace-level hexavalent chromium (Cr(VI)) in air. One of the difficulties in determining trace levels of Cr(VI) in air with conventional IC-DPC methods is co-elution of the solvent and ion peaks due to high concentrations of ionic compounds in the extract. However, by using gradient elution rather than isocratic elution we were able to fully resolve the Cr(VI) ion peak from the solvent peak without the need for diluting the extract, which would have reduced the minimum quantifiable level of the method. With this method, we were able to detect Cr(VI) in air at concentrations of 5.3 ng/m 3 (assuming a sampling volume of 1 m 3 and a final solution volume of 10 mL). Recovery tests at three different concentrations of Cr(VI) (50, 250, 1000 ng) were performed with or without fly ash; recovery rates at all the concentrations of Cr(VI), with or without fly ash, ranged from 68% to 110% (mean ± relative standard deviation, 96% ± 11%), and there were no differences in recovery rates with respect to the presence or absence of fly ash. Finally, we used the developed method to determine the concentration of Cr(VI) in stack gases collected from eight industrial waste incinerators located in Japan. The concentration of Cr(VI) in the stack gases ranged from below the method quantification limit to 3100 ng/m 3 . The highest concentrations of Cr(VI) detected in the stack gases were two to three orders of magnitude higher than that in ambient air in Japan. [ABSTRACT FROM AUTHOR]

National accounts for material stocks and flows are reported regularly by an increasing number of countries to promote a sustainable use of our natural resources. In this research we build upon the work of Herman Daly and Donella Meadows and propose a framework that links material stocks and flows to a conceptual hierarchy of ends and means which are societal benefit and natural capital. We introduce a set of six indicators that link together to quantitatively relate material consumption and societal benefits: material productivity, primary material use rate, stock retention time, stock productivity, service productivity, and service utilization. We apply this analytical framework to accounts of the material stocks and flows of Japan for the period 1990 to 2015. We find that Japan's material flow productivity doubled from 1.6 US$/kg to 3.2 US$/kg. This improvement can be primarily attributed to improvements in stock retention rates and circular material use, but has been offset by decreasing productivity of Japan's material stocks from 0.2 US$/kg to 0.14 US$/kg. We discuss the future potential of our indicator framework to include additional indicators for specific sectors and argue for the need for proper measurements of societal services and human wellbeing to enhance the policy implications of the indicator framework. • We present a framework of 6 indicators to study stocks, flows, and services. • The indicators address productivity, circularity, service provision, and wellbeing. • The framework quantifies the means-ends approach to sustainable development. • We apply this framework to new stock & flow accounts for Japan 1990–2015. • Japan's material productivity improved due to circularity and stock retention. [ABSTRACT FROM AUTHOR]

Front face fluorescence spectroscopy of typical Japanese soil powders (soil A: Typic Hapludand; soil H: Typic Hydraquent; soil Y: Typic Paleudult) has been conducted. Three dimensional excitation-emission matrix fluorescence spectra of the 100 wt% soils showed similar fluorescence patterns to each other. The fluorescence patterns were similar between the soil samples and their residues after extraction by NaOH solution for 60 min. In order to examine fluorescence extinction from a view point of whiteness of the soils, the soil powders were mixed with white and black diluents (Al 2 O 3 and Fe 3 O 4) and fluorescence spectra of the mixtures were measured at 450 nm excitation. At low levels of dilution with Al 2 O 3 (2–100 wt% of A; 50–100 wt% of H and Y), the fluorescence intensities increased with dilution. At high levels of dilution with Al 2 O 3 , the fluorescence intensities decreased with dilution. On the other hand, fluorescent intensities decreased by dilution with Fe 3 O 4. These results suggested inner filter effect-like fluorescence extinction by (1) large amount of blackish organic compounds giving high total carbon value and (2) blackish non-fluorescent mineral compounds. In order to correct the fluorescence intensities of the mixtures containing the sample soils and the diluents, we preliminary applied a correction method based on the Kubelka-Munk theory using diffuse reflectance. The corrected fluorescence intensities of samples with white diluents (Al 2 O 3) were described by a simple fluorescence response model having saturation values. Unlabelled Image • Front face fluorescence spectroscopy of typical Japanese soil powders was performed. • The soil powders showed 3D-EEM fluorescence patterns. • Inner filter effect-like fluorescence extinction by blackish compounds was suggested. • The extinction could be partly corrected by incorporating diffuse reflection. [ABSTRACT FROM AUTHOR]