Enhancing e-waste estimates: improving data quality by multivariate Input-Output Analysis

Rethinking time-lagged emissions and abatement potential of fluorocarbons in the post-Kigali Amendment era

The Montreal Protocol has been successful in safeguarding the ozone layer and curbing climate change. However, accurately estimating and reducing the time-lagged emissions of ozone-depleting substances or their substitutes, such as produced but not-yet-emitted fluorocarbon banks, remains a significant challenge. Here, we use a dynamic material flow analysis model to characterize the global stocks and flows of two fluorocarbon categories, hydrochlorofluorocarbons (HCFCs) and hydrofluorocarbons (HFCs), from 1986 to 2060. We assess emission pathways, time-lagged emission sizes, and potential abatement measures throughout different life cycle stages while focusing on the role of banked fluorocarbons in global and regional decarbonization efforts in the post-Kigali Amendment era. Although fluorocarbon releases are expected to decline, the cumulative global warming potential (GWP)-weighted emissions of HCFCs and HFCs are significant; these will be 6.4 (±1.2) and 14.8 (±2.5) gigatons CO2-equivalent, respectively, in 2022-2060 in our business-as-usual (BAU) scenario. Scenario analysis demonstrates that implementing currently available best environmental practices in developed economies can reduce cumulative GWP-weighted emissions by up to 45% compared with the BAU scenario.

Potential of metal recovery from printed circuit boards in Brazil

In this study, the generation of domestic waste electrical and electronic equipment (WEEE) and waste printed circuit board (WPCB) were estimated, from 2015 to 2030. Based on the number of EEE put on the Brazilian market, the possession rate in the Brazilian households and obsolescence amounts of five EEE types were estimated using time series. The results show that, between 2015 and 2030, the quantity of WEEE generated per year will increase from 131.87 kt to 195.22 kt. In this period, WPCB generation will stay around 10% of WEEE generation. Additionally, this study shows that the urban mining potential of the materials recoverable from WPCB can be an important revenue source, with environmental benefits deriving from energy savings and a reduction in CO2 emissions. The results of this study provide a quantitative basis that may help decision makers develop strategic policies for WEEE management, considering material circularity.

Generation estimation and metals recycling potentials evaluation of retired mobile phones in Korea

The goal of this work is to evaluate generation and metals recycling potentials of retired mobile phones in Korea. The generation estimation is conducted with the sales&new method and statistic data, such as sales of mobile phones and amount of the subscribers. The result shows that there are 17.99 million of mobile phones retired in 2022, compared 13.12 million in 2001. Accordingly, the deduced lifetime has minimum and maximum values in 2003 and 2020, which are 2.02 and 4.33 years, compared with 4.16 years in 2022 and 2.21 years in 2001. The deduced lifetime trends to increase with the increased values of subscribers and the fluctuated values of sales. The crosscheck testifies to the veracity of the result in comparison with the actual condition. The amount and dynamic of critical metals are also calculated with the content and amount of retired mobile phones.

Towards the definition of WEEE recycling targets in Ecuador. A case of study for mobile phones

The rise of consumption patterns of electrical and electronic equipment (EEE) and the generation of waste EEE (WEEE) has been strongly increasing globally. Recycling rates (RRs) are one of the main indicators for monitoring the progress towards a circular economy and establishing recovery and treatment schemes. For this reason, this study discusses the setting of recycling targets for WEEE in Ecuador, using mobile phones as a case study. Firstly, the generation of mobile phone waste from 2012 to 2018 is estimated based on literature review. The most appropriate model for estimating WEEE generation is selected according to the applicable market conditions, input requirements and available data. Then, the composition of a mobile phone is determined through an extensive literature review. Based on these results, the materials' environmental impact and potential economic value are approximated using the ReCiPe Endpoint (H, A) method and the prices of virgin materials, respectively. The estimation shows that in Ecuador an average of 2 million devices are discarded every year, which represents an interesting source of resources but currently does not have appropriate management. Ecuador has implemented regulatory frameworks in favour of the integral management of these wastes. However, mass-based collection targets still appear to be the only available measure. Therefore, national results on electronics recycling do not allow adequate monitoring of progress towards a circular economy and largely neglect environmental aspects and economic potential.

A first comprehensive estimate of electronic waste in Canada

Detailed analysis of electronic waste (e-waste) generation and composition is of utmost importance for the proper management of growing e-waste stream worldwide, containing both hazardous and valuable materials. Considering the absence of such comprehensive and up-to-date studies in Canada, this work presents the first estimate of put-on-market electrical and electronic equipment (EEE), the in-use stocks of EEE and e-waste generation in Canada from 1971 to 2030 for 51 product categories comprising 198 product types. Using a dynamic material flow analysis (MFA), the put-on-market EEE is estimated based on trade data retrieved from national and international import and export statistics, and the in-use stocks of EEE and the resulting e-waste are calculated using the Weibull distribution function. The results show that the total mass of EEE within the 60-year period is estimated to be 42.3 million tonnes, with an annual average growth rate of approximately 0.5%. By 2030, the total accumulated in-use stock of EEE is estimated to exceed 13 million tonnes. The estimated e-waste over the 60-year timespan is 29.1 million tonnes. The total annual e-waste generation in Canada is calculated to be 252 kilo tonnes (kt) and 954 kt in the years 2000 and 2020 respectively, which is estimated to reach 1.2 million tonnes by 2030. The e-waste generation per capita increased from 8.3 kg in 2000 to 25.3 kg in 2020 and is estimated to reach 31.5 kg by 2030. This quantification provides valuable insights to policymakers for setting up targets for waste reduction and identifying the resource circularity potential for efficient management of e-waste.

Prediction of e-waste generation: Application of modified adaptive neuro-fuzzy inference system (MANFIS)

An accurate estimation of generated electronic waste (e-waste) plays a pivotal role in the development of any appropriate e-waste management plan. The present study aimed to exploit modified adaptive neuro-fuzzy inference system (MANFIS) for the estimation of generated e-waste. There are different parameters affecting e-waste generation, the most important of which need to be identified to achieve the accurate estimation. The MANFIS used for parameter selection involves evaluating multiple choices between twelve initially specified parameters. The MANFIS models with five inputs have the highest mean R²_(train) and R²_(test) (0.978 and 0.952, respectively, in training and testing stages). According to the results, the best combination of parameters was related to legal imports of electrical and electronic equipment (EEE), smuggling (illegal) imports of EEE, exports of EEE, accumulation of EEE in Tehran, and accumulation of EEE in Iran with RMSE_(train) and RMSE_(test) of 0.221 and 2.221, respectively. The findings showed that the model with three triangular membership functions had the best performance; R²_(train) and RMSE_(train) values were 0.981 and 1.371, as well as R²_(test) and RMSE_(test) values were 0.971 and 1.678, respectively. Finally, the developed model was successfully applied for prediction of monthly e-waste generation in Tehran for thirteen selected electronic items. The obtained consistent results emphasized that appropriate selection of the number of input parameters and their combination, along with identifying optimal structure of MANFIS, provides a proper, simple and accurate prediction of e-waste.

Metal Requirements for Building Electrical Grid Systems of Global Wind Power and Utility-Scale Solar Photovoltaic until 2050

Wind and solar photovoltaic (PV) power form vital parts of the energy transition toward renewable energy systems. The rapid development of these two renewables represents an enormous infrastructure construction task including both power generation and its associated electrical grid systems, which will generate demand for metal resources. However, most research on material demands has focused on their power generation systems (wind turbines and PV panels), and few have studied the associated electrical grid systems. Here, we estimate the global metal demands for electrical grid systems associated with wind and utility-scale PV power by 2050, using dynamic material flow analysis based on International Energy Agency's energy scenarios and the typical engineering parameters of transmission grids. Results show that the associated electrical grids require large quantities of metals: 27-81 Mt of copper cumulatively, followed by 20-67 Mt of steel and 11-31 Mt of aluminum. Electrical grids built for solar PV have the largest metal demand, followed by offshore and onshore wind. Power cables are the most metal-consuming electrical components compared to substations and transformers. We also discuss the decommissioning issue of electrical grids and their recovery potential. This study would deepen the understanding of the nexus between renewable energy, grid infrastructure, and metal resources.

Improved Copper Circularity as a Result of Increased Material Efficiency in the U.S. Housing Stock

Material efficiency (ME) can support rapid climate change mitigation and circular economy. Here, we comprehensively assess the circularity of ME strategies for copper use in the U.S. housing services (including residential buildings and major household appliances) by integrating use-phase material and energy demand. Although the ME strategies of more intensive floor space use and extended lifetime of appliances and buildings reduce the primary copper demand, employing these strategies increases the commonly neglected use-phase share of total copper requirements during the century from 23-28 to 22-42%. Use-phase copper requirements for home improvements have remained larger than the demand gap (copper demand minus scrap availability) for much of the century, limiting copper circularity in the U.S. housing services. Further, use-phase energy consumption can negate the benefits of ME strategies. For instance, the lifetime extension of lower-efficiency refrigerators increases the copper use and net environmental impact by increased electricity use despite reductions from less production. This suggests a need for more attention to the use phase when assessing circularity, especially for products that are material and energy intensive during use. To avoid burden shifting, policymakers should consider the entire life cycle of products supporting services when pursuing circular economy goals.

Forecasting quantities of critical raw materials in obsolete feature and smart phones in Greece: A path to circular economy

Mobile phones represent an ever-increasing waste stream due to the increasing ownership and short lifetime. In particular, smartphones are among the most valuable e-waste because of their extremely high content of numerous key metals, specifically in the printed circuit board and magnets. As feature and smart phones contain different key metals at different concentrations, it is important to distinguish between the two phone types to make reliable estimations. This study presents estimations of obsolete mobile phones quantities, generated in Greece in 1995-2035 and the Critical Raw Materials (CRMs) and Precious Metals (PMs) embedded in them, making a differentiation between feature and smart phones. The dynamic material flow analysis is adopted, the lifespan is evaluated by the Weibull distribution and future sales are predicted by the logistic model incorporating phases of growth, saturation and decline. Then, the future wastes are predicted by the Market Supply A model. According to the results, the generation of obsolete smartphones is constantly increasing, while the waste flows of feature phones are declining. Efficient recycling of obsolete phones (1995-2020) can cover the demand for key metals (Au, Pd, Co) in the new smartphones for more than a decade in Greece, while the demand for Ag, Sb, Si, Zn, Be, Ti will be covered for more than 15 years. In 2020-2035 the accumulated amounts of CRMs and PMs, only from the smartphone waste, will be 1292.02 and 14.11 tonnes, respectively. The findings can contribute to the management of a valuable e-waste category closing the loop between resources-products-wastes.

Migration and Transformation of Multiple Heavy Metals in the Soil–Plant System of E-Waste Dismantling Site

E-waste generation has become a major environmental issue worldwide. Heavy metals (HMs) in e-waste can be released during inappropriate recycling processes. While their pollution characteristics have been studied, the migration and transformation of different multi-metal fractions in soil–plant system of e-waste dismantling sites is still unclear. In this study, pot experiments were conducted to investigate the migration and transformation of different multi-metal fractions (Cu, Pb, Zn and Al) in the soil–plant system using two Chinese cabbage cultivars (heavy metals low-accumulated variety of Z1 and non-low-accumulated Z2) treated with or without biochar. The result showed that the acid-soluble fraction of Cu, Pb, Zn and Al in soil decreased by 5.5%, 55.7%, 7.8% and 21.3%, but the residual fraction (ResF) of them increased by 48.5%, 1.8%, 30.9% and 43.1%, respectively, when treated with biochar and plants, compared to that of the blank soil (CK). In addition, Pb mainly existed as a reducible fraction, whereas Cu existed as an oxidisable fraction. Biochar combined with plants significantly increased the ResF of multi-metals, which reduced the migration ability of Pb among all other metals. The relative amount of labelled ¹³C in the soil of Z1 was higher than that of Z2 (25.4 fold); among them, the Gram-negative bacteria (18-1ω9c, 18-1ω7c) and fungi (18-2ω6c) were significantly labelled in the Z1-treated soil, and have high correlation with HM migration and transformation. In addition, Gemmatimonadete were significantly positive in the acid-soluble fraction of HMs, whereas Ascomycota mostly contributed to the immobilisation of HMs. Therefore, the distribution of fractions rather than the heavy metal type plays an important role in the HM migration in the soil–plant system of e-waste dismantling sites.

Assessing data in the informal e-waste sector: The Agbogbloshie Scrapyard

The Old-Fadama-Scrapyard, better known as Agbogbloshie, is located in Accra, Ghana. Over the last 20 years, the area has developed into a large scrapyard, where the informal sector processes mainly electronic waste (e-waste) and scrap metals. However, unsafe treatment methods, such as the open burning of cables and foams, and the spilling of hazardous liquids onto the ground, cause environmental pollution and create health risks by releasing persistent organic pollutants (POPs) and heavy metals. There is a recognized lack in literature of data on e-waste mass and material flows due to the lack of applicable methods to measure e-waste quantities in an informally managed treatment system. However, to establish sustainable e-waste management, e-waste mass and material flow data are crucial prerequisites. Therefore, the material flow analysis (MFA) methodology is proposed as a means for data collection within a limited time frame in the informal e-waste recycling context. In this case study, mass and material flows of e-waste processed at Agbogbloshie were estimated using two different approaches: Firstly, the kind, measures, constitution of load and number of loaded entering and exiting vehicles was observed and documented, and second, to validate the data collected, the mass and material flow of e-waste treatment processes on site were observed and documented. The resulting annual mass flows range between 13,090 t/a and 17,094 t/a of e-waste. Based on the data for Ghana from the Global E-waste Monitor, an average of 15,092 t/a (approximately 39% of the Ghanaian e-waste generation) is treated in Agbogbloshie.

Analysis of national policies for Circular Economy transitions: Modelling and simulating the Brazilian industrial agreement for electrical and electronic equipment

Public policies, incentives, and infrastructure are top-down instruments that can align stakeholders' roles and expectations for Circular Economy (CE) transitions, but it is crucial to analyse the possible effects of such instruments before implementation. This research investigates the Brazilian Industrial Agreement for Electrical and Electronic Equipment (BIAEEE) that governs the responsibilities and targets for nationwide collection and treatment of Waste from Electrical and Electronic Equipment (WEEE). A system dynamics simulation model is adapted for the use of smartphones in Brazil, and interventions focused on the collection of end-of-life products are examined against the BIAEEE targets. Twelve policy scenarios investigate three aspects of EEE collection: coverage increase, distribution of collection points and rewards. All scenarios show improvement in the EEE collection, but only one meets the BIAEEE targets. This research demonstrates how modelling and simulation can inform strategic decision-making in public policies for CE transitions.

Assessment of end-of-life electric vehicle batteries in China: Future scenarios and economic benefits

A better understanding of the waste of end-of-life batteries from electric vehicles (EVs) is a basis for their sustainable management. This study aims to estimate the waste of end-of-life EV batteries during 2006-2040 in China and to analyze the opportunities and challenges of subsequent utilization, based on a developed numerical model, real market data, and elaborately developed scenarios. The result shows that end-of-life batteries would increase from 0.1 to 7.8 thousand tons during 2012-2018, and then to 1500-3300 thousand tons in 2040. Of the waste streams, around 50% are estimated to be metal materials, representing great opportunities for battery recycling for material recovery. Economically, battery recycling for energy storage is estimated to create more economic benefits compared with that for material recovery solely (147.8 versus 76.9 billion US dollars). However, the supply of end-of-life batteries can hardly meet the demand for renewable energy storage in the near future, and a spatial mismatch of the supply and demand of energy storage capacity exists between the eastern and western regions in China. Accordingly, this study highlights national coordination for the rational layout of the collection, disassembly, and remanufacture facilities for the second use of end-of-life EV batteries in China.

Dynamic estimation of future obsolete laptop flows and embedded critical raw materials: The case study of Greece

The coronavirus pandemic has turned school and university learning system from classroom-based to exclusively online all over the world. As this change is accompanied by a spike in demand of laptops, an excessive amount of obsolete devices will be witnessed in the near future. Laptops are the most valuable e-waste category containing a high content of numerous critical raw materials, thus their waste management is crucial. Considering the impact of the coronavirus pandemic on the laptop lifespan, the future quantities and pieces of obsolete laptops in Greece are estimated (2016-2040), as well as the critical raw materials (CRMs) and precious metals (PMs) embedded in them, to illustrate the potential of recovering useful resources, thus contributing to a circular economy. To this end, dynamic material flow analysis is adopted, lifespan distribution is evaluated and future sales are predicted by the logistic model utilizing a bounding analysis. Then the future End-of-Life (EoL) laptop quantities are estimated taking time-varying parameters into consideration such as penetration rate, population, laptop weight and lifespan. This study is a dynamic estimation that avoids using average values adopted from literature that are not country specific. The provided information is useful for implementing national plans, improving the management of the most valuable category, EoL laptops, enhancing resources efficiency and contributing to a circular economy. The coronavirus pandemic has a similar impact on laptop sales in other countries, affecting their future laptop waste as well.

Towards a Smart E-Waste System Utilizing Supply Chain Participants and Interactive Online Maps

Efficient electronic waste (e-waste) management is one of the vital strategies to save materials, including critical minerals and precious metals with limited global reserves. The e-waste collection issue has gained increasing attention in recent years, especially in developing countries, due to low collection rates. This study aims to search for progressive solutions in the e-waste collection sphere with close-to-zero transport and infrastructure costs and the minimization of consumers’ efforts towards an enhanced e-waste management efficiency and collection rate. Along these lines, the present paper develops a smart reverse system of e-waste from end-of-life electronics holders to local recycling infrastructures based on intelligent information technology (IT) tools involving local delivery services to collect e-waste and connecting with interactive online maps of users’ requests. This system considers the vehicles of local delivery services as potential mobile collection points that collect and deliver e-waste to a local recycling enterprise with a minimum deviation from the planned routes. Besides e-waste transport and infrastructure costs minimization, the proposed smart e-waste reverse system supports the reduction of CO2 through the optimal deployment of e-waste collection vehicles. The present study also advances a solid rationale for involving local e-waste operators as key stakeholders of the smart e-waste reverse system. Deploying the business model canvas (BMC) toolkit, a business model of the developed system has been built for the case of Sumy city, Ukraine, and discussed in light of recent studies.

16S rRNA molecular profiling of heavy metal tolerant bacterial communities isolated from soil contaminated by electronic waste

Electronic waste is an evolving source of harmful pollutants in our surrounding environments and considered to be perilous as it contains toxic metals such as chromium, cadmium, lead, mercury, zinc, and nickel in huge quantities. Heavy metals are harmful contaminants and accumulated in the environment due to various anthropogenic activities. The present study was conducted to isolate and characterize different heavy metal tolerant bacterial species, based on molecular techniques from soil contaminated by electronic waste. The contaminated soil samples were analyzed for various physicochemical properties such as pH, electrical conductivity, soil moisture, water holding capacity, organic carbon, organic matter, available phosphorus, total nitrogen, and potassium using standard procedures. The soil samples were found to contain a higher amount of different heavy metals such as copper, chromium, lead, iron, cadmium, and nickel. Serial dilution and spread plate techniques have been used for bacterial isolation. The identification and molecular characterization of isolated bacterial species were done by biochemical tests and 16S rRNA gene sequencing technique. The 16S rRNA sequencing analysis confirmed the presence of different bacterial species as, Micrococcus aloeverae, Kocuria turfanensis, Bacillus licheniformis, Bacillus jeotgali, Bacillus velezensis, and Bacillus haikouensis. The findings indicated that the e-waste dumping sites are the storehouse of elite bacterial species. The present research study offers a platform for systematic analysis of e-waste sites by microbial profiling that may help in the innovation of novel microorganisms of scientific importance and better biotechnological potential.

A review of sustainable e-waste generation and management: Present and future perspectives

Studies on sustainable management of waste from electrical and electronic equipment (or e-waste) have gained increasing attention from researchers around the world in recent years, with investigations into various aspects of e-waste management were investigated. Studies on e-waste generation by previous papers have been reviewed to provide an overview of the current research progress and recommendations for future research. The relevant existing studies were collected from various databases. Using content analysis, three main aspects of the existing studies were evaluated: the distribution and trends of the publications, the scope and boundaries of the studies, and the current research practices and research applications. Although there was a significant increasing trend of the amount of research on the evaluation of e-waste generation, however, the number of publications based on the countries of origin was still small. Another limitation was found related to the differences in the selection of research subjects and the level of analysis resulted in variations in the scopes and boundaries of the existing studies. Various other research areas were investigated further based on their research findings, but the analysis of various methodological aspects was complicated due to the increasing number of newly developed methodologies and the lack of comprehensive and up-to-date reviews on this research area. Additionally, there was also a need to evaluate emerging and/or older technology, which led electrical appliances to be overlooked. We found that comprehensive and up-to-date reviews of the methodological aspects of e-waste generation are still lacking. Based on the research gaps and limitations discussed, recommendations for future research were made.

Electrostatic separation of aluminium from residue of electric cables recycling process

Cables and wires have a widespread use due to their application in electric power and data transmission. Since they consist of a conductive core (Cu or Al) and an insulating layer (polymer), they can be brought back to life after disposal through recycling in the form of secondary raw materials such as copper, aluminium and/or polymer. The aim of this paper is to research the possibilities of electrostatic separation use for separating aluminium left in residue fraction after the process of recycling Al waste electric cables, as well as to determine the influence of operating parameters and the optimal separation conditions. Waste fraction characterisation has determined that aluminium is mainly found in small-size particles (<2 mm) with the mass fraction higher than 60%. During the research planning the central composite design was used and three operating variables of an electrostatic separator were tested: roll speed, voltage and separation splitter position. Results have shown that it is possible to obtain a concentrate with the Al mass fraction of 97.86% at 91.20% recovery. It has been shown that the splitter position has the most significant influence on the grade of concentrate and recovery. It has also been shown that the roll speed individually and the interaction of the roll speed and splitter position have a significant influence on the grade of concentrate.

Mapping anthropogenic mineral generation in China and its implications for a circular economy

Anthropogenic mineral is absorbing wide concern in the context of circular economy, but its generation mechanism and quantity from product to waste remain unclear. Here we consider three product groups, 30 products, and use the revised Weibull lifespan model to map the generation of anthropogenic mineral and 23 types of the capsulated materials by targeting their evolution from 2010 to 2050. Total weight of anthropogenic mineral on average in China reached 39 Mt in 2010, but it will double in 2022 and quadruple in 2045. Stocks of precious metals and rare earths will increase faster than most base materials. The total economic potential in yearly-generated anthropogenic mineral is anticipated to grow markedly from 100 billion US$ in 2020 to 400 billion US$ in 2050. Furthermore, anthropogenic mineral of around 20 materials will be capable to meet projected consumption of three product groups by 2050.

While a large quantity of underground mineral resources can be converted into manufactured products, a majority is still solid waste disposal. Here the authors found a large increase in total weight of anthropogenic mineral from 2010 to 2050 with faster growth rate for precious metals.

Bi-objective design of household E-waste collection with public advertising and competition from informal sectors

The rapid expansion of technology, coupled with the falling prices of electronic products and their fast obsolescence, has resulted in a rapidly-growing amount of e-waste worldwide. Because of adverse effects on environment and public health, more and more countries and regions have begun to establish and operate public e-waste collection systems. In many developing countries, the low level of environmental awareness and the existence of informal sectors present obstacles to the success of such collection systems. This paper proposes to design a household e-waste collection network and launch a corresponding public service advertising campaign to counteract the informal recycling markets. The proposed mixed integer nonlinear program maximizes the amount of collected e-waste and minimizes overall costs of developing the network and its advertising campaign. A decomposition-based, multi-objective metaheuristic was developed to obtain the Pareto frontier. A case study based on the e-waste collection system in Changsha, China contextualizes the problem and developed methodology. Experiment results show that the cost of network construction and public advertising must be carefully balanced for limited budgets. The impact of residents' environmental awareness is also important to the collection effect. From a methodology perspective, this paper uses the Pareto analysis approach to study the design of household e-waste collection networks, with a supporting public service announcement campaign, in the presence of informal recycling markets. This paper also offers a policy design decision support tool to help regulators determine most workable policies that will balance the trade-offs between the two objectives.

Designing for Circularity—Addressing Product Design, Consumption Practices and Resource Flows in Domestic Kitchens

Both the daily use and renewal of kitchens significantly contribute to the overall environmental impact of domestic buildings. To identify design implications related to circular consumption in domestic kitchens, 20 household interviews and one focus group session were performed, investigating how kitchens are used and transformed to meet households’ wants and needs. This study determined that daily kitchen resource use is greatly affected by kitchen design and that typical kitchen design generally does not promote sustainable resource use. Key factors that support minimization of resource use in the kitchen are the availability and planning of storage and workspaces. Furthermore, kitchens should be equipped with functions that enable households to use energy and water efficiently. Regarding kitchen renewal, various motivations that may initiate kitchen renovations can be summarised as follows: (1) Functional demands and changing needs, (2) aesthetic demands and changing trends, (3) obsolescence due to wear, and (4) linkage to another home renovation. This article concludes that a combination of design strategies is needed to reach a higher level of kitchen circularity. Moreover, these design strategies must be accompanied by circular business models and efforts to increase awareness of the environmental impact related to activities in and involving the kitchen.

Economic consequences of consumer repair strategies for electrical household devices

Purpose

The purpose of this paper is to investigate to what extent a consumer’s repair strategy impacts the annual costs of ownership of a washing machine and two types of vacuum cleaner.

Design/methodology/approach

The annual cost of ownership is determined by calculating the annual life cycle cost (LCC) for the respective devices. The annual LCCs of the different scenarios allow a comparison of the different repair strategy options. A Monte Carlo simulation is run to introduce parameter variability. The device’s failure rate is estimated by a combination of data sets on the devices’ performance.

Findings

Results demonstrate that the repair of the devices considered is a more favourable option over replacement. A consumer who aims for the lowest annual LCC should allow for a high number of repairs per device, without putting a maximum on the cost per repair. However, the consumer should become more cautious when a device approaches the end of its expected lifetime. Finally, the purchase of warranty can be interesting when the warranty covers a sufficiently long proportion of the device’s (expected) lifetime and when its cost does not exceed a threshold proportion of the initial purchase price.

Research limitations/implications

The costs for repair might be overestimated. Future research can focus on the reduction of repair costs following self-repair.

Practical implications

The results provide strong arguments in favour of repair instead of replacement of broken devices.

Originality/value

This is the first research to quantify the influence of consumer behaviour in the context of repair of devices on the ownership costs of these devices.

Global trends and future prospects of e-waste research: a bibliometric analysis

Electronic waste (e-waste) has been widely studied by scholars all over the world, but the research topics and development trends in this field are still unclear. This study aimed to explore the status quo, hot topics, and future prospects in the field of e-waste. Data of publications were downloaded from the Web of Science Core Collection. We used CiteSpace V, Histcite, and VOSviewer to analyze literature information. A total of 2800 papers in e-waste research were identified, and the number of publications increased rapidly after 2004. Six thousand five hundred seventy-three authors participated in the e-waste research, but 70.01% of the authors published only 1 article. The most productive country in this field was China (1146 publications), and the most productive institution was the Chinese Academy of Sciences (370 publications). The Waste Management (225 publications) was the most productive journal, and Environment Science & Technology (9704 co-citations) was the most co-cited journal. The main hot topics in e-waste field were management and recycling of e-waste in developing countries, health risk assessment after exposure to organic pollutants, degradation and recovery of waste metal materials, and impact of heavy metals on children's health. The frontier topic was degradation.

Understanding Consumer E-Waste Recycling Behavior: Introducing a New Economic Incentive to Increase the Collection Rates

Consumer electronics are made of a wide range of materials, including precious metals and critical minerals with limited global reserves. Ensuring the recycling of these materials is essential for future use, especially since many renewable energy solutions are based on them. In addition, improper end-of-life treatments of these products cause harm to the environment and human health. This study explores the incentives that have been used to increase consumer collection rates for end-of-life electrical and electronic equipment (EoL EEE). Based on extensive global literature reviews, we propose an alternative to existing consumer incentives. The research suggests that implementing an economic incentive based on the electronic bonus card system (EBCS) has several benefits compared to existing incentives. It compensates the consumers for the transaction costs of proper collection and satisfies the consumer perception of EoL EEE as having a residual value. However, application of the EBCS motivation technology will require the cooperation of various stakeholders, including electronics producers and national and international authorities.

Emission behaviors of nitro- and oxy-polycyclic aromatic hydrocarbons during pyrolytic disposal of electronic wastes

Emission factors (EFs) of polycyclic aromatic hydrocarbon (PAH) derivatives (12 nitro-PAHs and 4 oxy-PAHs) during the pyrolysis of two types of electronic waste (E-waste) were measured. Compositional profile, particle size distribution, gas-particle partitioning, correlations with precursor species and influences of pyrolytic temperature were investigated. The derivative products were dominated by oxy-PAHs. The averaged EFs of oxy-PAHs were 3.37 ± 4.10 μg/g and 32.6 ± 18.1 μg/g for PWBs and plastic casings, respectively, and those of nitro-PAHs were 85.7 ± 92.4 ng/g and 83.3 ± 69.7 ng/g, respectively. Most EFs of derivative species significantly correlated with their corresponding parent PAHs (p < 0.05), except a few cases, indicating formation of derivatives via related reactions of parent species. Most nitro-PAHs occurred in fine particles with the size < 2.1 μm, and oxy-PAHs were prevailing in fine particles with the size between 0.4 μm and 2.1 μm. Proportions of oxy-PAHs in particulate phase, especially those with higher molecular weight, were noticeably greater than those of the corresponding parent species. Below 480 °C, there was no evident difference in the EFs of PAH derivatives, while the EFs noticeably increased from 520 °C. With the increasing temperature, the majority of oxy-PAHs still occurred on finer particles, while the contribution of coarser particles tended to increase.

Estimating the generation of household e-waste in municipalities using primary data from surveys: A case study of Sao Jose dos Campos, Brazil

Estimating the generation of Waste from Electrical and Electronic Equipment (WEEE) in municipalities is relevant for the adequate planning of take-back systems. However, current WEEE estimation studies have focused primarily at the country level, and relied mostly on secondary data from literature, especially when adopting discrete average lifespans for each type of appliance. This paper aims at developing and applying a WEEE estimation method in a Brazilian city, by obtaining primary data that reflects the differences in WEEE generation among the various social and economic profiles in the city. A survey with a stratified sample was carried out to collect representative data from each city Zone. Results show that lifespan distributions are most desirable for WEEE estimation studies than discrete averages, and that the lifespan profiles in the city are considerably different than previous values adopted in other Brazilian studies. Results also show significant variations of lifespan profiles for different types of WEEE among the different Zones of the city, which reflect the social and economic differences.

Estimating the Evolution of Urban Mining Resources in Hong Kong, Up to the Year 2050

Rapid urban metabolism is causing many resources to flow from consumption to waste. But many of these wastes could be secondary resources, and cities could become urban mines and an increasing supply of future resources. Hong Kong, one of the most developed and populated cities in the world, has demonstrated a completely metabolic evolution to be an urban mine, since the 1970s. Covering 14 types of e-waste and eight types of end-of-life vehicles, this study first investigates Hong Kong's evolution as an urban mine. The potential output weight of the urban mine quickly grew from 117 kt in 2000 to 368 kt in 2014, and it is estimated to remain in the range of 300-350 kt over the years 2015-2050, with 40-50 kg/cap/year. The economic potential of urban mining, for 18 metals, plastic, glass, and rubber tires, will be approximately US$2 billion annually, mainly contributed by precious and rare metals. All the obtained results contribute to Hong Kong's waste management and promise to have positive impact on urban mining and circular economy for other, less-developed cities or regions.

Impacts of heavy metals and soil properties at a Nigerian e-waste site on soil microbial community

Heavy metal contamination is a serious problem worldwide threatening soil environment and human health. In the present study, concentrations of 6 heavy metals at an electronic waste (e-waste) site in Nigeria were correlated to their mobility, showing distinct distribution pattern between surface soils and subsoils. Proteobacteria, Firmicutes, Acidobacteria and Planctomycetes dominated the indigenous soil microbial communities, and there was significant discrimination of bacterial taxonomic composition between the heavy metal contaminated and uncontaminated areas. The abundance of most bacterial taxa changed with heavy metal contamination level to different extent. The multivariate regression tree (MRT) analyses illustrated that main environmental variables influencing bacterial taxonomic composition included soil texture (31%) and organic carbon (14%), whereas microbial diversity was affected by soil pH (32%) and soil texture (14%). Our results surprisingly indicated that soil properties were more influential in determining soil bacterial composition and diversity than heavy metals even at the e-waste site which was seriously contaminated by heavy metals. The present study contributes to a deeper insight into the key environmental variables shaping the diversity and composition of soil microbes at heavy metal contaminated e-waste sites.

Changes of waste generation in Australia: Insights from structural decomposition analysis

Waste generation is linked to consumption both in households (Final demand) and in the supply chain. Gaining understanding into the driving forces that change of waste generation in the supply chain can contribute to solving issues of waste management. The environmentally-extend input-output model is an effective tool with which to investigate the relationship between economic activities and waste generation. In this paper structural decomposition analysis (SDA) is employed to analyse the determinants of changes of waste generation in Australian economy from 2007-2008 to 2013-2014. Empirical results indicate that the major determinant for the increase of waste generation was change in Final demand's overall level of economic activity. Changes in the production mix of Final demand (mix effect) was responsible for a decrease of waste generation in Australian economy during the period. The Manufacturing sector was found to have the highest waste generation intensity. Meaning that each million $AUD output of the Manufacturing sector resulted in the most amount of waste generation. In addition, technological change has contributed the largest waste generation effect for the Construction sector in 2011-2012. These findings suggest that Final demand, technological changes and sectoral changes are identified as the drivers of Australian waste generation historically. To reduce waste generation, policy must be targeted at altering behaviour of consumption and waste generation, and increasing innovation of new ecological technologies for Australian industry.

Assessment of solid waste generation and treatment in the Australian economic system: A Closed Waste Supply-Use model

The Household sector (HS) is not only the major cause of waste generation in industrial sectors, but also the same function as an industrial sector to generate waste. Current researches mainly focus on waste generation caused by the demand of the HS based on the environmentally-extend input-output (EEIO) models while the effect of the HS as an industrial sector on waste flow has not been analysed. In addition, there is uncertainty around the economic cost of waste management discussed in EEIO models due to the lack of the calculation of the cost of labor. We adjust waste supply-use table to analyse effects of the HS as an industrial sector on waste flow, resulting in closed waste supply-use table (CWSUT). The novelty of the method lies in a shift in the effect of the HS, from an exogenous factor to an endogenous factor. Results derived from Australian CWSUT in 2009-10 illustrate waste generation effects of intermediate sectors and the mixed waste flows of the HS. The definition of "intermediate sector" is that the sector consumes intermediate inputs from producing sectors and generates intermediate outputs to Final demand. They show that: (1) the Construction sector has the largest waste generation effects, in which the amount of masonry waste has accounted for the most direct and total effects of waste generation; (2) investigations regarding the HS in CWSUT can calculate the amount of direct and total waste generation, the monetary flow, and effects of the Income for the Household sector. Base on the above results, the paper puts forwards the application of the CWSUT on other types of environmental issues and waste policies.

An Effectiveness Assessment of China's WEEE Treatment Fund

Policy is essential to the management of waste electrical and electronic equipment (WEEE). In order to present valuable findings for policy improvement, we performed a quantitative effectiveness assessment of China’s WEEE treatment fund from 2012 to 2015. The achievement of the general goal of the WEEE treatment fund was evaluated with various indicators. We calculated the values of all indicators and analyzed the changes in them. The results show that the WEEE treatment fund was important in promoting WEEE collection and recycling activities and has provided great benefits in the form of resources and the environment. Moreover, the authorized enterprises also experienced progress in their development. In a word, the WEEE treatment fund was effective to some extent. However, because of the limited subsidies and other factors, the WEEE treatment fund had different effects on five categories of WEEE. We found that its approach worked best for the TV set. Although the promotional effects on the other four categories of WEEE have been increasingly significant since 2014, there is room for improvement. Fortunately, the subsidy rates have been adjusted by administrations and new subsidies were provided in 2016. As it is crucial for the effectiveness of the WEEE treatment fund, new subsidy rates should be evaluated regularly.

Scenarios for Demand Growth of Metals in Electricity Generation Technologies, Cars, and Electronic Appliances

This study provides scenarios toward 2050 for the demand of five metals in electricity production, cars, and electronic appliances. The metals considered are copper, tantalum, neodymium, cobalt, and lithium. The study shows how highly technology-specific data on products and material flows can be used in integrated assessment models to assess global resource and metal demand. We use the Shared Socio-economic Pathways as implemented by the IMAGE integrated assessment model as a starting point. This allows us to translate information on the use of electronic appliances, cars, and renewable energy technologies into quantitative data on metal flows, through application of metal content estimates in combination with a dynamic stock model. Results show that total demand for copper, neodymium, and tantalum might increase by a factor of roughly 2 to 3.2, mostly as a result of population and GDP growth. The demand for lithium and cobalt is expected to increase much more, by a factor 10 to more than 20, as a result of future (hybrid) electric car purchases. This means that not just demographics, but also climate policies can strongly increase metal demand. This shows the importance of studying the issues of climate change and resource depletion together, in one modeling framework.

E-Waste Recycling System in Closed Loop Supply Chain

This article describes how technology growth and the lifecycle of devices and also other tendencies for buying new devices all cause a huge mass of electronic waste. Due to materials used in production which are dangerous or valuable metals, the environmental aspects and natural resources make electronic waste management and electronic waste recycling a pressing subject. This article studies electronic waste recycling and its importance in research of closed loop supply chain management and the impact of electronic waste recycling. Using structural equation modelling to study the factors, data was collected from 120 expert questionnaires and analyzed by SPSS and SmartPLS. Causal relationships among the studied factors and efficacy coefficients of each factor were identified by the fuzzy DEMATEL technique. Finally, the dynamic model was plotted by VENSIM.

Global Lithium Flow 1994-2015: Implications for Improving Resource Efficiency and Security

Lithium has been widely recognized as an essential metal for next-generation clean technologies. With the aim of identifying opportunities for improving lithium resource efficiency and security, this study establishes a long-term trade-linked material flow analysis framework to analyze lithium flow throughout the technological life cycle and across national boundaries during the 1994-2015 period. The results indicate that with broader purposes identified, global lithium production and consumption experienced rapid growth over the past decades. A widely distributed, actively functioning lithium trade network has been established, with the United States, China, the European Union, Chile, and Australia playing essential roles. Global lithium in-use stock, which is mainly embodied in ceramics and glass, reached 29 kilotons in 2015. The lithium stock contained in battery-related applications, together with the huge potential production of stock in future decades, represents a major opportunity for secondary lithium recovery. In the context of intensive international trade, international cooperation on lithium waste management is extremely important. It is also suggested that there is a high risk of lithium shortage for countries with strong dependence on lithium import. The establishment of domestic lithium reserves may be an option for these countries.

Combined analyses of costs, market value and eco-costs in circular business models: eco-efficient value creation in remanufacturing

Eco-efficient Value Creation is a method to analyse innovative product and service design together with circular business strategies. The method is based on combined analyses of the costs, market value (perceived customer value) and eco-costs. This provides a prevention-based single indicator for ‘external environmental costs’ in LCA. The remanufacturing of products is an environmental and sustainable approach, in the circular economy, and can deliver lower eco-costs of materials depletion and pollution. From a business point of view, however, remanufacturing seems to be viable in B2B niche markets only. In consumer markets, remanufacturing is less common. The question is how can remanufacturing become a viable business solution for mainstream consumer markets. Traditional ‘green’ marketing approaches are not enough: green has a positive, but also negative connotations, so marketing approaches are complex. By using the Eco-efficient Value Creation method, marketing strategies for the roll-out of remanufacturing in mainstream consumer markets, can be revealed. This approach has led to the development of five aspects, which are key to innovative circular business models, for remanufacturing: (1) buyers differ from the buyers of the ‘new product’ (2) quality must be emphasised in all communications (3) risk must be taken away from the buyer (4) top level service is required to convince the buyer (5) a ‘green’ brand may support the remanufactured product image.

Flow, stock, and impact assessment of refrigerants in the Japanese household air conditioner sector

Refrigerants provide society with great benefits while have the potential to cause adverse effects on the environment and human health. The present study estimated time-dependent flows and stocks and assessed the effects of refrigerants (R-22, R-410a, and R-32) in household air conditioners in Japan. It was found that stock of R-22 and R-410a peaked at 49,147t in 2000 and 55,994t in 2017, respectively. The largest flow of R-22 and R-410a to waste phase occurred at 3417t/yr. in 2005 and 4011t/yr. in 2023, respectively. The total global warming potential (GWP) due to refrigerant emissions increased from 3.6kt CO₂ eq. in 1952 to 6999kt CO₂ eq. in 2019, and then decreased to 5314kt CO₂ eq. in 2030. The ozone depletion potential (ODP) peaked at 141t CFC-11 eq. in 2002. When substituting R-410a for R-22, the ODP decreased 50% while the GDP increased 8%. When substituting R-32 for R-410a, there was no effect on the ODP while the GDP decreased 6%. The human health damage due to the global warming effect of refrigerant emission was much higher than that due to the ozone depleting effect. The refrigerant emission in use and waste management phases dominated the human health damage. The dynamic estimation not only allows us to evaluate the performance of past policies but also supports the future sustainable management associated with the health effects of refrigerants.

Use, Storage, and Disposal of Electronic Equipment in Switzerland

Electronic devices contain important resources, including precious and critical raw materials. For an efficient management of these resources, it is important to know where the devices are located, how long they are used and when and how they are disposed of. In this article, we explore the past and current quantities of electronic devices in the in-use stock and storage stock in Switzerland and quantify the flows between the use, storage and disposal phase with dynamic material flow analysis (MFA). Devices included are mobile phones, desktop and laptop computers, monitors, cathode ray tube and flat panel display televisions, DVD players, and headphones. The system for the dynamic MFA was developed as a cascade model dividing the use phase in first, second and further use, with each of these steps consisting of an in-use stock and a storage stock for devices. Using a customized software tool, we apply Monte Carlo simulation to systematically consider data uncertainty. The results highlight the importance of the storage stock, which accounts for 25% (in terms of mass) or 40% (in terms of pieces) of the total stock of electronic devices in 2014. Reuse and storage significantly influence the total lifetime of devices and lead to wide and positively skewed lifetime distributions.

Where next on e-waste in Australia?

For almost two decades waste electrical and electronic equipment, WEEE or e-waste, has been considered a growing problem that has global consequences. The value of recovered materials, primarily in precious and base metals, has prompted some parts of the world to informally and inappropriately process e-waste causing serious environmental and human health issues. Efforts in tackling this issue have been limited and in many ways unsuccessful. The global rates for formal e-waste treatment are estimated to be below the 20% mark, with the majority of end-of-life (EoL) electronic devices still ending up in the landfills or processed through rudimentary means. Industrial confidentiality regarding device composition combined with insufficient reporting requirements has made the task of simply characterizing the problem difficult at a global scale. To address some of these key issues, this paper presents a critical overview of existing statistics and estimations for e-waste in an Australia context, including potential value and environmental risks associated with metals recovery. From our findings, in 2014, on average per person, Australians purchased 35kg of electrical and electronic equipment (EEE) while disposed of 25kg of WEEE, and possessed approximately 320kg of EEE. The total amount of WEEE was estimated at 587kt worth about US$ 370million if all major metals are fully recovered. These results are presented over the period 2010-2014, detailed for major EEE product categories and metals, and followed by 2015-2024 forecast. Our future projection, with the base scenario fixing EEE sales at 35kg per capita, predicts stabilization of e-waste generation in Australia at 28-29kg per capita, with the total amount continuing to grow along with the population growth.

Assessing the role of informal sector in WEEE management systems: A System Dynamics approach

Generally being ignored by academia and regulators, the informal sector plays important roles in Waste Electrical and Electronic Equipment (WEEE) management systems, especially in developing countries. This study aims: (1) to capture and model the variety of informal operations in WEEE management systems, (2) to capture the dynamics existing within the informal sector, and (3) to assess the role of the informal sector as the key player in the WEEE management systems, influencing both its future operations and its counterpart, the formal sector. By using System Dynamics as the methodology and India as the reference system, this study is able to explain the reasons behind, on the one hand, the superiority of the informal sector in WEEE management systems and, on the other hand, the failure of the formal systems. Additionally, this study reveals the important role of the second-hand market as the determinant of the rise and fall of the informal sector in the future.

The Abandoned E-Waste Recycling Site Continued to Act As a Significant Source of Polychlorinated Biphenyls: An in Situ Assessment Using Fugacity Samplers

The recycling of e-waste has attracted significant attention due to emissions of polychlorinated biphenyls (PCBs) and other contaminants into the environment. We measured PCB concentrations in surface soils, air equilibrated with the soil, and air at 1.5-m height using a fugacity sampler in an abandoned electronic waste (e-waste) recycling site in South China. The total concentrations of PCBs in the soils were 39.8-940 ng/g, whereas the concentrations in air equilibrated with the soil and air at 1.5 m height were 487-8280 pg/m(3) and 287-7380 pg/m(3), respectively. The PCB concentrations displayed seasonal variation; they were higher in winter in the soils and higher in summer in the air, indicating that the emission of PCBs from the soil was enhanced during hot seasons for the relatively high temperature or additional sources, especially for low-chlorinated PCBs. We compared two methods (traditional fugacity model and fugacity sampler) for assessing the soil-air partition coefficients (Ksa) and the fugacity fractions of PCBs. The results suggested that the fugacity sampler provided more instructive and practical estimation on Ksa values and trends in air-soil exchange, especially for low-chlorinated PCBs. The abandoned e-waste burning site still acted as a significant source of PCBs many years after the prohibition on open burning.

Quantifying Domestic Used Electronics Flows using a Combination of Material Flow Methodologies: A US Case Study

This paper describes the scope, methods, data, and results of a comprehensive quantitative analysis of generation, stock, and collection of used computers and monitors in the United States , specifically desktops, laptops, CRT monitors, and flat panel monitors in the decade leading up to 2010. Generation refers to used electronics coming directly out of use or postuse storage destined for disposal or collection, which encompasses a variety of organizations gathering used electronics for recycling or reuse. Given the lack of actual statistics on flows of used electronics, two separate approaches, the sales obsolescence method (SOM) and the survey scale-up method (SSUM), were used in order to compare the results attained and provide a range for estimated quantities. This study intentionally sought to capture the uncertainty in the estimates. To do so, uncertainty in each data set was incorporated at each stage using Monte Carlo simulations for SOM and establishing scenarios for SSUM. Considering the average results across both methods, we estimate that in 2010 the U.S. generated 130-164 thousand metric tons of used computers and 128-153 thousand tons of used monitors, of which 110-116 thousand tons of used computers and 105-106 thousand tons of used monitors were collected for further reuse, recycling, or export. While each approach has its strengths and weaknesses, both the SOM and the SSUM appear to be capable of producing reasonable ranges of estimates for the generation and collection of used electronics.

Environmental pollution of electronic waste recycling in India: A critical review

The rapid growth of the production of electrical and electronic products has meant an equally rapid growth in the amount of electronic waste (e-waste), much of which is illegally imported to India, for disposal presenting a serious environmental challenge. The environmental impact during e-waste recycling was investigated and metal as well as other pollutants [e.g. polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs)] were found in excessive levels in soil, water and other habitats. The most e-waste is dealt with as general or crudely often by open burning, acid baths, with recovery of only a few materials of value. As resulted of these process; dioxins, furans, and heavy metals are released and harmful to the surrounding environment, engaged workers, and also residents inhabiting near the sites. The informal e-waste sectors are growing rapidly in the developing countries over than in the developed countries because of cheapest labor cost and week legislations systems. It has been confirmed that contaminates are moving through the food chain via root plant translocation system, to the human body thereby threatening human health. We have suggested some possible solution toward in which plants and microbes combine to remediate highly contaminated sites.

Estimation of the Unregistered Inflow of Electrical and Electronic Equipment to a Domestic Market: A Case Study on Televisions in Vietnam

Waste electrical and electronic equipment (WEEE) constitutes one of the most problematic waste streams worldwide, and accurately estimating the scale of WEEE can assist in tackling its associated issues. However, obtaining an accurate estimation of WEEE remains a challenge because a share of the waste is difficult to calculate. This share stems from the administratively unregistered (so-called "invisible") inflow of electrical and electronic equipment (EEE) into the domestic market. As a first attempt to qualitatively and quantitatively investigate this invisible inflow, this study discusses the nature of this flow in detail and proposes a calculation pathway for quantifying its magnitude. The size of the invisible inflow to a domestic market (assumed equal to invisible sales) is calculated by subtracting the registered, also called "visible", sales from the total sales. The total sales are modeled, whereas the visible sales are derived from statistical data. The method is illustrated by a case study on televisions (TVs) in Vietnam. The results show that from 2002 to 2013, the invisible TV inflow contributed, on average, 15% to the total TV sales (coefficient of variation: 0.21). This average share would increase by approximately 1.0% when the maximum number of TVs used per household increased by 1.0%. However, it would decrease by 1.7% when the visible sales increased by 1.0%. Additionally, the average share of the invisible TV inflow would change from 15% to 27% when an unadjusted constant instead of an adjusted time-varying lifespan is employed. This first estimation of the invisible EEE inflow to the domestic market can be improved with additional knowledge and data in the future.

Uncovering the Recycling Potential of "New" WEEE in China

Newly defined categories of WEEE have increased the types of China's regulated WEEE from 5 to 14. Identification of the amounts and valuable-resource components of the "new" WEEE generated is critical to solving the e-waste problem, for both governmental policy decisions and recycling enterprise expansions. This study first estimates and predicts China's new WEEE generation for the period of 2010-2030 using material flow analysis and the lifespan model of the Weibull distribution, then determines the amounts of valuable resources (e.g., base materials, precious metals, and rare-earth minerals) encased annually in WEEE, and their dynamic transfer from in-use stock to waste. Main findings include the following: (i) China will generate 15.5 and 28.4 million tons WEEE in 2020 and 2030, respectively, and has already overtaken the U.S. to become the world's leading producer of e-waste; (ii) among all the types of WEEE, air conditioners, desktop personal computers, refrigerators, and washing machines contribute over 70% of total WEEE by weight. The two categories of EEE-electronic devices and electrical appliances-each contribute about half of total WEEE by weight; (iii) more and more valuable resources have been transferred from in-use products to WEEE, significantly enhancing the recycling potential of WEEE from an economic perspective; and (iv) WEEE recycling potential has been evolving from ∼16 (10-22) billion US$ in 2010, to an anticipated ∼42 (26-58) billion US$ in 2020 and ∼73.4 (44.5-103.4) billion US$ by 2030. All the obtained results can improve the knowledge base for closing the loop of WEEE recycling, and contribute to governmental policy making and the recycling industry's business development.

Systematic characterization of generation and management of e-waste in China

Over the last decade, there has been much effort to promote the management of e-waste in China. Policies have been affected to prohibit imports and to control pollution. Research has been conducted in laboratories and on large-scale industrial operations. A subsidy system to support sound e-waste recycling has been put in place. However, the handling of e-waste is still a concern in China and the issue remains unresolved. There has been relatively little work to follow up this issue or to interpret continuing problems from the perspective of sustainable development. This paper first provides a brief overview of conventional and emerging environmental pollution in Chinese "famous" e-waste dismantling areas, including Guiyu in Guangdong and Wenling in Zhejiang. Environmentalists have repeatedly proven that these areas are significantly polluted. Importing and backyard recycling are decreasing but are ongoing. Most importantly, no work is being done to treat or remediate the contaminated environmental media. The situation is exacerbated by the rising tide of e-waste generated by domestic update of various electronics. This study, therefore, employs a Sales Obsolescence Model approach to predict the generation of e-waste. When accounting for weight, approximately 8 million tons of e-waste will be generated domestically in 2015, of which around 50% is ferrous metals, followed by miscellaneous plastic (30%), copper metal and cables (8%), aluminum (5%), and others (7%). Of this, 3.6% will come from scrap PCBs and 0.2% from lead CRT glass. While more and more end-of-life electronics have been collected and treated by formal or licensed recyclers in China in terms of our analysis, many of them only have dismantling and separation activities. Hazardous e-wastes, including those from PCBs, CRT glass, and brominated flame retardant (BFR) plastics, have become problematic and probably flow to small or backyard recyclers without environmentally sound management. Traditional technologies are still being used to recover precious metals--such as cyanide method of gold hydrometallurgy--from e-waste. While recovery rates of precious metals from e-waste are above 50%, it has encountered some challenges from environmental considerations. Worse, many critical metals contained in e-waste are lost because the recovery rates are less than 1%. On the other hand, this implies that there is opportunity to develop the urban mine of the critical metals from e-waste.

An evaluation of the potential yield of indium recycled from end-of-life LCDs: A case study in China

With the advances in electronics and information technology, China has gradually become the largest consumer of household appliances (HAs). Increasingly, end-of-life (EOL) HAs are generated in China. EOL recycling is a promising strategy to reduce dependence on virgin production, and indium is one of the recycled substances. The potential yield of indium recycling has not been systematically evaluated in China thus far. This paper estimates the potential yield of recycled indium from waste liquid crystal displays (LCDs) in China during the period from 2015 to 2030. The quantities of indium that will be used to produce LCDs are also predicted. The estimates focus on the following three key LCD waste sources: LCD TVs, desktop computers and portable computers. The results show that the demand for indium will be increasing in the near future. It is expected that 350 tonnes of indium will be needed to produce LCDs in China in 2035. The indium recycled from EOL LCDs, however, is much less than the demand and only accounts for approximately 48% of the indium demand. The sustainable index of indium is always less than 0.5. Therefore, future indium recycling efforts should focus on the development of recycling technology and the improvement of the relevant policy.

Forecasting waste compositions: A case study on plastic waste of electronic display housings

Because of the rapid succession of technological developments, the architecture and material composition of many products used in daily life have drastically changed over the last decades. As a result, well-adjusted recycling technologies need to be developed and installed to cope with these evolutions. This is essential to guarantee continued access to materials and to reduce the ecological impact of our material consumption. However, limited information is currently available on the material composition of arising waste streams and even less on how these waste streams will evolve. Therefore, this paper presents a methodology to forecast trends in the material composition of waste streams. To demonstrate the applicability and value of the proposed methodology, it is applied to forecast the evolution of plastic housing waste from flat panel display (FPD) TVs, FPD monitors, cathode ray tube (CRT) TVs and CRT monitors. The results of the presented forecasts indicate that a wide variety of plastic types and additives, such as flame retardants, are found in housings of similar products. The presented case study demonstrates that the proposed methodology allows the identification of trends in the evolution of the material composition of waste streams. In addition, it is demonstrated that the recycling sector will need to adapt its processes to deal with the increasing complexity of plastics of end-of-life electronic displays while respecting relevant directives.

Systematic characterization of generation and management of e-waste in China

Over the last decade, there has been much effort to promote the management of e-waste in China. Policies have been affected to prohibit imports and to control pollution. Research has been conducted in laboratories and on large-scale industrial operations. A subsidy system to support sound e-waste recycling has been put in place. However, the handling of e-waste is still a concern in China and the issue remains unresolved. There has been relatively little work to follow up this issue or to interpret continuing problems from the perspective of sustainable development. This paper first provides a brief overview of conventional and emerging environmental pollution in Chinese "famous" e-waste dismantling areas, including Guiyu in Guangdong and Wenling in Zhejiang. Environmentalists have repeatedly proven that these areas are significantly polluted. Importing and backyard recycling are decreasing but are ongoing. Most importantly, no work is being done to treat or remediate the contaminated environmental media. The situation is exacerbated by the rising tide of e-waste generated by domestic update of various electronics. This study, therefore, employs a Sales Obsolescence Model approach to predict the generation of e-waste. When accounting for weight, approximately 8 million tons of e-waste will be generated domestically in 2015, of which around 50% is ferrous metals, followed by miscellaneous plastic (30%), copper metal and cables (8%), aluminum (5%), and others (7%). Of this, 3.6% will come from scrap PCBs and 0.2% from lead CRT glass. While more and more end-of-life electronics have been collected and treated by formal or licensed recyclers in China in terms of our analysis, many of them only have dismantling and separation activities. Hazardous e-wastes, including those from PCBs, CRT glass, and brominated flame retardant (BFR) plastics, have become problematic and probably flow to small or backyard recyclers without environmentally sound management. Traditional technologies are still being used to recover precious metals--such as cyanide method of gold hydrometallurgy--from e-waste. While recovery rates of precious metals from e-waste are above 50%, it has encountered some challenges from environmental considerations. Worse, many critical metals contained in e-waste are lost because the recovery rates are less than 1%. On the other hand, this implies that there is opportunity to develop the urban mine of the critical metals from e-waste.