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Understanding the factors affecting consumer replacement behavior is important in extending the product lifetime in a circular economy. Although such factors have been widely investigated, methodologies to quantitatively measure the potential of changes in these aspects are scarce. They help to consider effective strategies for product lifetime extension. This study focused on the expected product lifetime and constructed a framework to analyze this potential, using air conditioners in Japan as a case study. When the expected product lifetime increased by 1, 2, and 3 years, the mean actual product lifetime rose by 0.9, 1.8, and 2.72 years, respectively, whose values can be sufficiently recognized as potentials for product lifetime extension. The results indicate that products and services for product lifetime extension can actually be used by consumers. Therefore, business strategies for product lifetime extension can increase resource efficiency and potentially strengthen competitiveness in future resource constraint economies. [ABSTRACT FROM AUTHOR]

This study combined a dynamic discrete choice model for air conditioner replacement decisions with an inter-industry model in order to evaluate the economic impact of Japan's Home Appliance Eco-Point Program, an appliance replacement program that was in effect from May 2009 to March 2011. Focusing on air conditioners produced from 1995 to 1999 and replaced during the period from 2005 to 2013, we found that the eco-point program increased replacement probabilities by 1.5% to 1.9% in 2009. Moreover, the program produced an additional output of 31,337 million yen and a total value added of 21,259 million yen. However, the benefit–cost ratio – determined by dividing the increase in value added by the monetary value of the points awarded for appliance replacement – was only 0.68. From a cost-benefit perspective, the program can be judged not to have been an effective policy measure. [ABSTRACT FROM AUTHOR]

Our objective was to provide the information necessary to efficiently recover metals from end-of-life lithium-ion secondary batteries by assessing the metal content by year of production. In addition, we analyzed the concentrations of Sn and the toxic metals Pb, Cr, and Cd in battery pack components, including printed circuit boards and cables. Li and Co were the only active substances in the cathode materials of lithium-ion secondary batteries produced from 1997 to 2005. Ni and Mn also were used in cathode materials of batteries produced from 2007 to 2011. However, Ni became the main constituent in 2012, and Mn was not detected in batteries from that year. For printed circuit boards and cables, Pb concentrations from 1997 to 2004 ranged from 6451 to 12,107 mg/kg, but from 2005 onward maximum concentrations were 513 mg/kg, clearly showing that substitution for Pb had been completed a year before the EU Restriction on Hazardous Substances (RoHS) Directive came into effect. [ABSTRACT FROM AUTHOR]

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]

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: 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]

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]

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]

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]