Potential reuse of small household waste electrical and electronic equipment: Methodology and case study

Designing a sustainable reverse logistics network for used cell phones based on offline and online trading systems

Unsustainable production and consumption are driving a significant increase in global electronic waste, posing substantial environmental and human health risks. Even in more developed nations, there is the challenge of low collection rates. In response, we integrate offline and online trading systems and design a material efficiency strategy for used cell phones. We propose a new multi-objective optimization framework to maximize profit, carbon emissions reduction, and circularity in the process of recycling and treatment. Considering multi-period, multi-product, multi-echelon features, as well as price sensitive demand, incentives, and qualities, we established a new multi-objective mixed-integer nonlinear programming optimization model. An enhanced, Fast, Non-Dominated Solution Sorting Genetic Algorithm (ASDNSGA-II) is developed for the solution. We used operational data from a leading Chinese Internet platform to validate the proposed optimization framework. The results demonstrate that the reverse logistics network designed achieves a win-win situation regarding profit and carbon emission reduction. This significantly boosts confidence and motivation for engaging in recycling efforts. Online recycling shows robust profitability and carbon reduction capabilities. An effective coordination mechanism for pricing in both online and offline channels should be established, retaining offline methods while gradually transitioning towards online methods. To increase the collection rate, it is essential to jointly implement a transitional strategy, including recycling incentives and subsidy policies. Additionally, elevating customer environmental awareness should be viewed as a long-term strategy, mitigating the cost of increasing collection rates during the market maturity stage (high collection rates).

Incorporating self-employed maintainers into WEEE formal recycling system: A system dynamic approach

The establishment and operation of a formal recycling system for waste electrical and electronic equipment is an important measure to reduce environmental hazards and improve the recycling of resources, but how to incorporate self-employed maintainers into the system has formed an important research gap. Based on the perspective of extended producer responsibility, we argue that self-employed maintainers are required to assume the corresponding environmental responsibility for the environmental externality caused by informal maintenance activities. Using qualitative structural analysis techniques of system dynamics approach with quantitative simulation analysis techniques, we construct an incentive model for self-employed maintainers' participation in formal recycling system, based on which we propose four incentive strategies. A simulation analysis is further conducted by using the case of waste mobile phones recycling in Qingdao to verify the effectiveness of our incentive model and strategies.

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 Novel ILP Formulation for PCB Maintenance Considering Electrical Measurements and Aging Factors: A “Right to Repair” Approach

The design of longer-lasting products, such as domestic electric appliances, is a key-stone approach of the circular economy to reduce the use of non-reusable materials and the number of wastes to be managed at the end of the product’s life as well as to extend it. The manufacturing of modern electric appliances includes the incorporation of printed circuit boards (PCBs). PCBs provide mechanical support and electrically connect electrical or electronic components using conductive trackpads and other features etched from one or more sheet layers of copper laminated onto and/or between sheet layers of a non-conductive substrate. This paper proposes a PCB maintenance framework, fully compliant with the “Right to Repair” concept, considering the impact of their aging failures based on measurements made on them, as well as the repair and replacement costs of their components. Herein, we present an algorithm that assesses the problem of handling the repair and replacement cost corresponding to specific failures while ensuring that the total cost of repair does not exceed a predefined value. This is achieved through an integer linear programming (ILP) formulation which maximizes the benefit to the life expectancy, Li, of an appliance, constrained by a customer’s limited budget. The proposed methodology is tested with different PCBs and considers different types of appliances. More specifically, two cases concerning PCBs of washing and dishwasher machines are studied to examine the dependency of the solutions on the aging rate of their various components. The simulation results show that considering a medium budget, after 3 years, we can achieve a health benefit of 92.4% for a washing machine’s PCB, while for a dishwasher’s PCB, the health benefit drops to 86.3%.

Promotion of Household Waste Utilization in China: Lessons Learnt from Three Case Studies

Household waste utilization has been regarded as an important pathway to promote the circular economy paradigm and sustainable development for a long time. However, relevant enterprises are facing dilemmas in terms of the backward disposal methods for food waste, inadequate recycling of low-value recyclable waste and the lack of leading enterprises, resulting in unsustainable expansion of the industry. To address these problems, we investigated governmental departments and 20 household waste utilization enterprises in China. From the investigation, three typical enterprises, representing the advanced technology for food waste, the recycling mode of recyclable waste and the cultivation mode of leading enterprises, were selected for case studies. The results indicate that applying the technology of bioconversion by maggots could improve the utilization of food waste and adopting the “online and offline” dual-channel mode could benefit the recycling of low-value recyclable waste. Additionally, leading enterprises can be cultivated by franchise mode, which can drive the utilization of household waste in China effectively. The findings enrich the theory of household waste utilization in terms of disposal methods, recycling modes and enterprise operation. Practically, this research should enlighten decision-makers to improve household waste utilization. Furthermore, the research results could be generalized in other countries, thereby advancing the household waste management worldwide.

Municipal solid waste collection systems: An indicator to assess the reusability of products

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Reuse assessment of WEEE: Systematic review of emerging themes and research directions

The reuse of Waste Electrical and Electronic Equipment (WEEE) is deemed the best end-of-life option in terms of the environmental impact and socio-economic benefits. Taking this cue, this paper applies a systematic literature review to map the existing knowledge base to present the major and emerging themes of the reuse assessment of WEEE. In all, 12,216 articles published from 2005 to 2019 in the Web of Science, ProQuest, and Google Scholar are collected, from which 331 articles are shortlisted for review. The shortlisted articles are divided into two sub-periods 2005-2014 and 2015-2019 to draw out the development of the research themes and the contribution of the recent research articles to the literature on WEEE reuse assessment. Bibliographic coupling combined with keyword analysis is performed using SciMat and VOSViewer. The results inform that the major ongoing themes are Consumer behaviour towards use, disposal, collection, reuse, repair and recycling of WEEE; Assessing the potential of WEEE for reuse; Product recovery strategy and market analysis for WEEE remanufacturing; and Material flow analysis of WEEE in circular economy. The research themes of Informal WEEE management in developing countries; Impact of government subsidy on WEEE management; and Product service system and circular economy deserve further attention. In the articles reviewed, mobile phones and computers are extensively studied for WEEE reuse assessment followed by refrigerators and televisions. Assessing the environmental impact and legal aspects of WEEE reuse, cross-border movements and flow in secondary markets, policies and regulations on the purchase of reprocessed WEEE, and the reprocessing and revenue made by the informal sector in developing countries are possibilities for future research.

Sustainable Solutions for Wearable Technologies: Mapping the Product Development Life Cycle

Wearable technologies involve the integration of technology into clothing or accessories to bring new functionalities for people on the move. Many examples of wearables are emerging, from simple fitness tracking watches to electronics deeply embedded into garments for multi-touch sensing and control for personal music players. Without careful development, wearables can have a negative impact on the environment due to increased production of electronic components, increased e-waste from abandoned devices, and increased energy usage. We examine environmental sustainability issues through a review of recent research and cases across three broad areas including the fashion industry, information and communications technology (ICT), and wearable technologies. In the analysis, we examine stages in the product life cycle and identify the unique issues for each sector, including the extraction of materials, production process, distribution of products, use, and disposal of products that have reached the end of their life. The findings are gathered as implications for design so that researchers, educators, designers, developers, and product managers will gain an overview of the issues related to environmental sustainability. Related examples of products and prototypes are provided to enable informed choices during the design and development of wearables that are more environmentally sustainable.

Ascending the Waste Hierarchy: Re-use potential in Swedish recycling centres

According to the waste hierarchy principle, which constitutes the basis of European waste legislation, waste prevention and re-use are considered – most of the times – better waste management options than recycling. However, prevention and re-use activities are difficult to operationalise and measure, without a monitoring framework in place. This contribution investigates the potential of re-using end-of-life products that have been disposed at recycling centres in Sweden. Recycling centres receive a wide variety of materials for recycling, of which a portion could be re-used instead. The aim is to identify what product groups can be re-used, the share of these potentially re-usable products in the recycling centres, and under what conditions their re-use is feasible. A literature review of similar studies, site visits at recycling centres in Sweden, and semi-structured interviews with relevant stakeholders were used to analyse the potential for re-use in private recycling centres in Sweden. The most suitable product groups for re-use identified are building materials, furniture and electrical equipment (mainly white goods), as other material types are mostly handled by charity organisations (e.g. textiles). There is significant potential for increasing re-use operations in recycling centres, but in order to be economically profitable it is important to identify the most suitable material fractions (or product groups) and engage in strategic partnerships that will allow more effective organisation of re-use processes.

A Preparation for Reuse Trial of Washing Machines in Ireland

This paper presents the results of a “preparation for reuse” trial of washing machines in Ireland. For the trial, a methodology for the quantitative assessment of potentially reusable appliances in the waste electric and electronic equipment (WEEE) stream is developed and applied to a statistically significant sample allowing the study to quantify a theoretical potential for the “preparation for reuse” of washing machines in the WEEE stream in Ireland under current collection conditions. For a statistically significant sample size, data on preparation for re-use trials conducted on B2C (Business-to-Consumer) WEEE was collected and reviewed. From the 23,129 appliances which were accepted into the trial, the study found that 327 of these washing machines were successfully prepared for reuse and sold back into the Irish market, leading to an overall reuse rate of 1.5%. A quantitative analysis of the trial data is presented with a complimentary qualitative evaluation which provides insights into the causes for this low reuse figure, the occurrence of specific repairs and recommended actions to address these.

Repair vs. replacement: Selection of the best end-of-life scenario for small household electric and electronic equipment based on life cycle assessment

This study presents a methodology designed for selecting, from an environmental point of view, the best end-of-life scenario for electric and electronic equipment which breaks before the end of its life span. To this end, the environmental impact of the life cycle of the equipment is evaluated for two different end-of-life scenarios: repair & reuse vs. replacement. As a case study, the proposed methodology is applied to a representative sample of nine categories of small household electric and electronic equipment (120 appliances). Repair & reuse scenarios consider the life span and the typical failures and repairs associated with each electric and electronic equipment category and the use of the repaired equipment until the remaining life span after its breakage. Replacement scenarios also consider the life span associated to each electric and electronic equipment category and the replacement of the broken equipment by an equivalent during the remaining life span after its breakage. The environmental impact obtained for both scenarios for each small household electric and electronic equipment category is compared in order to identify the best end-of-life scenario. To do so, the life cycle assessment methodology is applied, using CML and ReCiPe as midpoint- and endpoint-impact assessment methods, respectively. The results indicate that for all the analysed categories, the repair & reuse scenarios generally prove environmentally better than replacement scenarios, as Directive 2012/19/EU promotes. However, for some types of failure, e.g. those related to motors or printed circuit boards, if the failure occurs at the end of its life span, replacement is a better option than repair & reuse, since the environmental impact of the repair activities is not offset by the environmental benefits of extending the useful life until the end of the life span.

How to meet reuse and preparation for reuse targets? Shape advertising strategies but be aware of "social washing"

Preparation for reuse (PfR) is a fundamental waste management practice that is second only to prevention in the waste hierarchy. The paper, building on advertising literature, investigates how to leverage the pro-social nature of this option for giving products that have become waste a second life. To examine how advertising strategies based on emotional, functional or combined stimuli can be used to increase intention to buy these items, we carried out an experiment on 507 actual visitors a PfR items shop run by a social cooperative in Northern Italy. We found that, depending on consumers' social involvement, both emotional and functional stimuli based on the social impact of preparation for reuse tend to outperform functional stimuli and have a positive impact on brand attitudes by shaping attitudes to advertisements. Purchasing behaviour has a positive impact on attitudes toward the PfR organization and moderates the effect of emotional and combines stimuli on attitudes toward the advertisement. Since emotional stimuli can be freely used by both legitimated and opportunistic companies, the former should seek to preserve their value proposition by making it easier for consumers to recognise actually trustworthy organizations. This is possible combining the use of advertisements with the development of solid customer relationships. To this end, awareness campaigns, closer relationships with stakeholders and third-party verifiable standards and certifications should be considered to reduce the risk of "social washing" in the current second-hand market context.

Identifying design guidelines to meet the circular economy principles: A case study on electric and electronic equipment

This study presents a methodology that allows the analysis of how an existing product design meets the design guidelines required from the circular economy perspective, and which are the design guidelines that would need to be incorporated into its design to become a better circular design product. For that, as a starting point, the design guidelines required for the circular product design have been identified from an extensive literature review. Then, criteria have been defined to measure the margin of improvement of a product design based on the level of compliance of each circular design guideline, and the relevance of each circular design guideline for the specific product category to which it belongs. Finally, the methodology has been applied to a representative sample of 127 appliances belonging to different categories of small household electrical and electronic equipment. The circular design guidelines related to extending life span and to product/components reuse have been identified as those that more urgently need to be incorporated, while the urgency of those related to connectors or product structure is moderate.

Accounting for the environmental benefits of remanufactured products: Method and application

Although the importance of reusing products has been stated frequently, both in legislation and by academics, the scientific literature does not provide comprehensive and systematic methods of assessing the reuse of a generic product from an environmental point of view. Moreover, the definitions of reuse provided in the literature and legislation are not always consistent. This article introduces an original classification of different types of reuse, including some suggested definitions. It then focuses on remanufacturing, a type of reuse in which a used product (or its components) is returned to at least its original performance level. The article describes the development of a method for assessing, from a life-cycle perspective, the potential environmental benefits of remanufacturing energy-related products. The method includes several novel aspects: it helps to analyse possible trade-offs between potential environmental impacts and energy efficiency; it allows the independent modelling of some parameters that influence product reuse; and it can be applied even at the early stages of the design process, when some specifications may not yet have been defined. The environmental impacts of a product's life-cycle stages are used as input parameters for the assessment. The method is then applied to an enterprise server, a case-study product for which remanufacturing is a current market practice. A sensitivity analysis is included to check how uncertainties could affect the overall results. The results of the case study show that remanufactured servers, even those that are less energy efficient, can have lower environmental impacts than new ones. For example, reusing some components (e.g. hard disk drives and memory cards) is environmentally beneficial even if the remanufactured server consumes up to 7% more energy than a newly manufactured server. The case study also demonstrates how the method proposed could be used in the context of product policy discussions.

Modelling the correlations of e-waste quantity with economic increase

Waste from Electrical and Electronic Equipment (WEEE or e-waste) is regarded as one of the fastest growing waste streams in the world and is becoming an emerging issue owing to adverse consequences on the natural environment and the human health. This research article reveals the presence of a strong linear correlation among global e-waste generation and Gross Domestic Product. The obtained results indicate that the best fit for data can be reached by comparing e-waste collected volumes and GDP PPS. More in detail, an increase of 1000 GDP PPS means an additional 0.27kg of e-waste collected and 0.22kg of e-waste reused/recycled. Furthermore, for each additional citizen, there will be an increase of 7.7kg of e-waste collected and 6.2kg of e-waste reused/recycled. The better collection of e-waste acts an important role concerning the circular economy, and it can be an advantageous approach. Therefore, e-waste could be considered as an opportunity for recycling or recovery of valuable metals (e.g., copper, gold, silver, and palladium), given their significant content in precious metals than in mineral ores.

A survey on consumers' attitude towards storing and end of life strategies of small information and communication technology devices in Spain

This study analyses the current habits and practices towards the store, repair and second-hand purchase of small electrical and electronic devices belonging to the category of information and communication technology (ICT). To this end, a survey was designed and conducted with a representative sample size of 400 individuals through telephone interviews for the following categories: MP3/MP4, video camera, photo camera, mobile phone, tablet, e-book, laptop, hard disk drive, navigator-GPS, radio/radio alarm clock. According to the results obtained, there is a tendency to store disused small ICT devices at home. On average for all the small ICT categories analysed, 73.91% of the respondents store disused small ICT devices at home. Related to the habits towards the repair and second-hand purchase of small ICT devices, 65.5% and 87.6% of the respondents have never taken to repair and have never purchased second-hand, respectively, small ICT devices. This paper provides useful and hitherto unavailable information about the current habits of discarding and reusing ICT devices. It can be concluded that there is a need to implement awareness-raising campaigns to encourage these practices, which are necessary to reach the minimum goals established regarding preparation for reuse set out in the Directive 2012/19/EU for the category small electrical and electronic equipment.

Attitude of the stakeholders involved in the repair and second-hand sale of small household electrical and electronic equipment: Case study in Spain

The European legal framework for Electrical and Electronic Equipment (EEE) and Waste Electrical and Electronic Equipment (WEEE) (Directive 2012/19/EU) prioritises reuse strategies against other valorisation options. Along these lines, this paper examines the awareness and perceptions of reusing small household EEE from the viewpoint of the different stakeholders involved in its end-of-life: repair centres, second-hand shops and consumers. Direct interviews were conducted in which an intended survey, designed specifically for each stakeholder, was answered by a representative sample of each one. The results obtained from repair centres show that small household EEE are rarely repaired, except for minor repairs such as replacing cables, and that heaters, toasters and vacuum cleaners were those most frequently repaired. The difficulty of accessing cheap spare parts or difficulties during the disassembly process are the commonest problems observed by repair technicians. The results obtained from second-hand shops show that irons, vacuum cleaners and heaters are the small household EEE that are mainly received and sold. The results according to consumers indicate that 9.6% of them take their small household EEE to be repaired, while less than 1% has ever bought a second-hand small household EEE. The main arguments for this attitude are they thought that the repair cost would be similar to the price of a new one (for repairs), and hygiene and cleaning reasons (for second-hand sales).

Disassembly properties and material characterisation of household small waste electric and electronic equipment

This paper is focused on characterising small waste electric and electronic equipment, specifically small household appliances, from two different points of views: disassembly properties and material identification. The sample for this characterisation was obtained from a selective collection campaign organised in Castellón de la Plana (Spain). A total amount of 833.7kg (749 units) of small waste electric and electronic equipment was collected, of which 23.3% by weight and 22.4% by units belonged to the subcategory household equipment. This subcategory, composed of appliances such as vacuum cleaners, toasters, sandwich makers, hand blenders, juicers, coffee makers, hairdryers, scales, irons and heaters, was first disassembled in order to analyse different aspects of the disassembly process for each equipment type: type of joints, ease of identification of materials, ease of access to joints for extracting components, ease of separation of components from the whole, uniformity of tools needed for the disassembly process and possibility of reassembly after disassembly. Results show that the most common joints used in these equipment types are snap-fits and screws, although some permanent joints have also been identified. Next, the material composition of each component of each appliance belonging to each equipment type was identified visually and with additional mechanical trials and testing. It can be observed that plastic and electric/electronic components are present in all the equipment types analysed and are also the material fractions that appear with higher percentages in the material composition: 41.1wt% and 39.1wt% for the plastic fraction and electric/electronic components, respectively. The most common plastics are: polypropylene (PP), acrylonitrile butadiene styrene (ABS) and polycarbonate (PC), while the most common electric/electronic components are: cable, plug and printed circuit boards. Results also show that disassembly properties and material characterisation vary widely from one equipment type to another.