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Waste electrical and electronic equipment (WEEE) has become a critical environmental problem. Catalytic pyrolysis is an ideal technique to treat and convert the plastic fraction of WEEE into chemicals and fuels. Unfortunately, research using real WEEE remains relatively limited. Furthermore, the complexity of WEEE complicates the analysis of its pyrolytic kinetics. This study applied the Fraser-Suzuki mathematical deconvolution method to obtain the pseudo reactions of the thermal degradation of two types of WEEE, using four different catalysts (Al2O3, HBeta, HZSM-5, and TiO2) or without a catalyst. The main contributor(s) to each pseudo reaction were identified by comparing them with the pyrolysis results of the pure plastics in WEEE. The nth order model was then applied to estimate the kinetic parameters of the obtained pseudo reactions. In the low-grade electronics pyrolysis, the pseudo-1 reaction using TiO2 as a catalyst achieved the lowest activation energy of 92.10 kJ/mol, while the pseudo-2 reaction using HZSM-5 resulted in the lowest activation energy of 101.35 kJ/mol among the four catalytic cases. For medium-grade electronics, pseudo-3 and pseudo-4 were the main reactions for thermal degradation, with HZSM-5 and TiO2 yielding the lowest pyrolytic activation energies of 75.24 and 226.39 kJ/mol, respectively. This effort will play a crucial role in comprehending the pyrolysis kinetic mechanism of WEEE and propelling this technology toward a brighter future.

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Managing e-waste involves collecting it, extracting valuable metals at low costs, and ensuring environmentally safe disposal. However, monitoring this process has become challenging due to e-waste expansion. With IoT technology like LoRa-LPWAN, pre-collection monitoring becomes more cost-effective. Our paper presents an e-waste collection and recovery system utilizing the LoRa-LPWAN standard, integrating intelligence at the edge and fog layers. The system incentivizes WEEE holders, encouraging participation in the innovative collection process. The city administration oversees this process using innovative trucks, GPS, LoRaWAN, RFID, and BLE technologies. Analysis of IoT performance factors and quantitative assessments (latency and collision probability on LoRa, Sigfox, and NB-IoT) demonstrate the effectiveness of our incentive-driven IoT solution, particularly with LoRa standard and Edge AI integration. Additionally, cost estimates show the advantage of LoRaWAN. Moreover, the proposed IoT-based e-waste management solution promises cost savings, stakeholder trust, and long-term effectiveness through streamlined processes and human resource training. Integration with government databases involves data standardization, API development, security measures, and functionality testing for efficient management.

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Waste electrical and electronic equipment (WEEE) is defined as "urban mines" due to the various recoverable minerals they contain. However, current WEEE classification methods are mostly limited to their physical characteristics, focusing on collection, transport, and treatment purposes rather than on valorization. In the present study, our aim is to propose an alternative classification approach adapted for low-income countries for WEEE recovery that highlights their content of precious and valuable metals. A typology of WEEE was created based on WEEE generated in Ouagadougou (Burkina Faso). Principal component analysis (PCA) and the moving center technique (K-means) were used for the classification method. Ultimately, we have found that to improve the recovery of WEEE, they can be classified into three main groups: (i) a group of WEEE-containing batteries, (ii) a group of WEEE-containing valuable and precious metals, and finally, (iii) a group of WEEE made up of cathode ray tube televisions (CRT-TV) waste. The WEEE belonging to the second group are the ones that could generate higher economical values. This alternative classification approach will help investors and operators to better orient their valorization activities towards WEEE types that present the best precious metals recovery potential, maximizing their profits. On the other hand, decision-makers will find this classification useful for reorganizing the WEEE value chain.

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Every year an estimated two million tonnes of waste electrical and electronic equipment (WEEE) are discarded by householders and companies in the United Kingdom (UK). While the UK has left the European Union (EU), its waste-related policies still mirror those of the EU, including the WEEE-related policies. Motivated by the recent introduction the so-called 'Right to Repair' policy for electrical and electronic equipment (EEE) across the EU and UK, this paper aims to demonstrate that, depending on the commitment and behavioural changes by the consumers and the government, the future of the WEEE management of the UK will vary. To this end, focusing on landfilled WEEE reduction we develop a generic system dynamics model and apply it to eleven WEEE categories. They depict the flow of EEE and WEEE representing the interaction among the stakeholders (e.g., consumers and producers of EEE) and relevant government regulations of the UK. Our four scenario analyses find that longer use of EEE and better WEEE collection seem to be effective in reducing landfilled WEEE, while more reuse and more recycling and recovery have negligible impacts, despite excluding the additional generation of landfilled WEEE as a result of recycling and recovery. Comparing with the business-as-usual scenario, one year longer EEE use and 10% more of WEEE collection could at maximum reduce landfilled WEEE by 14.05% of monitoring and control instruments and 93.93% of display equipment respectively. Backcasting scenario analyses reveal that significant efforts are required to reduce the targeted amounts.

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The production and consumption of electronic goods have experienced a significant increase over the years, leading to a substantial surge in the global volume of electronic waste, commonly referred to as Waste Electrical and Electronic Equipment (WEEE). The selection of a sustainable location for WEEE recycling plants plays a crucial role in mitigating environmental concerns, preserving resources and promoting economic development. It signifies a proactive and responsible approach to electronic waste management in the contemporary world. To tackle the challenge of selecting sustainable locations for WEEE recycling plants, this study employed the Entropy and Entropy and Evaluation based on Distance from Average Solution (EDAS) methodologies, evaluating 10 alternative cities in Turkey based on 13 criteria. The selected criteria include land cost, personnel cost, energy cost, availability of labour, government support degree, tax preferences, road network accessibility, number of electronic equipment producers, existence of recycling plants, suitability of land use, population and availability of renewable resources (wind power and solar energy). The Entropy method was employed to calculate the weights assigned to each criterion, whereas the EDAS method was utilized to evaluate the decision alternatives. The results provide region-specific recommendations, such as Antalya for the Mediterranean region and Samsun for the Black Sea region. The literature lacks sufficient research on the selection of sustainable locations for WEEE recycling plants. Furthermore, the utilization of real data enhances the study's credibility and provides practical insights for decision-making. The selection of a sustainable location for a WEEE recycling plant in Turkey not only demonstrates the country's environmental commitment but also sets a global example for responsible waste management.

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Tremendous amounts of electric and electronic wastes (e-waste) are generated daily, and their indiscriminate disposal may cause serious environmental pollution. The recovery of non-metallic materials from e-waste is a strategy to not only reduce the volume of e-waste but also avoid pollutant emissions produced by indiscriminate disposal of e-waste. Pyrolysis, sub/supercritical water treatment, chemical dissolution, and physical treatment (e.g., ball milling, flotation, and electrostatic separation) are available methods to recover useable non-metallic materials (e.g., resins, fibers, and various kinds of polymers) from e-waste. The e-waste-derived materials can be used to manufacture a large variety of industrial and consumer products. In this regard, this work attempts to compile relevant knowledge on the technologies that derive utilizable materials from different classes of e-waste. Moreover, this work highlights the potential of the e-waste-derived materials for various applications. Current challenges and perspectives on e-waste upcycling to useable materials are also discussed.

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With an increase in the amount of waste electrical and electronic equipment (WEEE), the waste of resources and environmental hazards caused by WEEE cannot be ignored. Meanwhile, the lack of environmental awareness among consumers and the existence of informal recyclers pose a great challenge to the government in governing the WEEE recycling industry. This study constructs a tripartite evolutionary game model consisting of the government and formal and informal recyclers. Then, the payoff matrix, replicator dynamic equations and all the equilibrium points are obtained, and a stability analysis of the equilibrium points is performed to derive the evolutionary stability strategies (ESSs) and their formation conditions. Finally, the influence of important parameters on the WEEE recycling industry is examined through numerical analysis. The results suggest that the government cannot ignore the existence of informal recyclers but should take governance measures to intervene in informal recycling and guide such recyclers to upgrade their processing technology. Moreover, the willingness of informal recyclers to invest in processing technology increases with the increase in environmental damage taxes. Second, the government should provide formal recyclers with appropriate promotional subsidies. Third, the government should control its own cost of governance and reduce its financial burden. Fourth, with government subsidies, formal recyclers should decide whether to make promotional investments based on the investment cost and the sum of the benefits from the investment and government subsidy. Finally, under government tax pressure and the influence of formal recyclers' promotional investments, informal recyclers should actively invest in processing technology.

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The surge in Waste Electrical and Electronic Equipment (WEEE) generation, reaching 53.6 million metric tons (Mt) in 2019, demands efficient recycling solutions. This study focuses on the Shredder Light Fraction (SLF), a material stream derived from the mechanical pre-processing of WEEE, which is considered "municipal waste". SLF constitutes 4.2% of the output material and is rich in metals like copper, tin, lead, zinc, silver, and gold. Pyrolysis treatment was applied to SLF, enabling recyclability. Both batch and continuous setups were employed for materials flow analysis and technical evaluation of the resource potential. The research evaluates the impact of pyrolysis technology on solid fraction metal content and pyrolysis gas/oil energy potential. Scaling up the process addressed material heterogeneity and increased the reliability of the obtained results. An innovative pyrometallurgical extraction approach was suggested, to recover valuable metals in SLF which otherwise could be lost via energy recovery methods. The resulting solid product after pyrolysis showed enriched concentrations of copper, zinc, lead, and precious metals with concentrations acceptable for industrial use. Additionally, it displayed reduced mass and diminished hazardous constituents. The non-condensable gas, rich in hydrogen, carbon monoxide, and methane, exhibited potential as an alternative energy source or reducing agent in the metallurgical sector. This research advances metal recycling from SLF, offering valuable insights for environmental impact mitigation as waste was transformed into a valuable by-product for potential use in the copper industry.

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The waste electrical and electronic equipment (WEEE) stream in Thailand shifted from exporting WEEE to recycling them in domestic enterprises after China's import restrictions on e-waste in 2018. This study aims to investigate the pollution status, pollution sources, and ecological risk of heavy metals from manual WEEE dismantling facilities (12 repair shops and 8 junk shops) in the Nakhon Si Thammarat province of southern Thailand by examining the concentrations of As, Cd, Ni, and Pb in the topsoil (0-15 cm) during the wet and dry seasons. The results revealed that the mean concentrations of all heavy metals were higher during the dry season than in the wet season. The concentrations of analyzed soil heavy metals decreased as the intensity of e-waste dismantling activities increased, with recycling sites > repair sites > control sites (no e-waste recycling activities). Only 10% of WEEE processing workshops (junk shops) had soil Pb and As concentrations that exceeded Thailand's residential soil quality standards. However, ecological indexing models based on the geo-accumulation index found that 75% of electric repair shops were contaminated with the analyzed heavy metals, particularly Pb. Moreover, the Nemerow integrated pollution index indicated that 16.7% of electric repair shops were on the pollution warning line. Our findings suggest that policymakers should promote ecological risk assessment as a method for mitigating the negative environmental impact of electronic repair businesses, which are widely dispersed in residential areas and tend to dominate the WEEE stream because of the circular economy concept of "right to repair", and highlight the decline of junk shops and e-waste dismantling villages for waste export resulting from China's ban.

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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.

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The disposal practises and preferences of household waste from electrical and electronic equipment disposal (WEEE) are essential components in material flow analysis (MFA). Nevertheless, the synergistic of consumers' behaviours and preferences with the disposal of different WEEE has yet to be investigated in depth. This study examined several consumer features of WEEE management using a quantitative questionnaire survey, including consumers' disposal behaviours and preferences. As a Malaysian federal government administrative centre, and model of a contemporary and sustainable Malaysian city, Putrajaya was chosen as the study area. Using stratified random sampling, the questionnaire was distributed through face-to-face and online surveys among households across 20 precincts within Putrajaya. From June 2021 to January 2022, 500 surveys were distributed over seven months, and IBM SPSS Statistic version 26 was used to analyse the data. The result shows that 80% of respondents have a good knowledge of WEEE management and are fully aware of the dangerous materials they have in their WEEE. 75% said they would recycle their WEEE, but only 44% said they would separate it from other household wastes. It was also shown that 88% of the household were willing to pay a collection fee of at least RM 10 for each collection. This analysis found that Extended Producer Responsibility (EPR) mechanisms can assist in overcoming weaknesses in WEEE management by including beneficial schemes to incentivise consumers to improve current waste policies. In the meantime, governments, media, and local non-governmental organisations may help by increasing awareness of effective and sustainable WEEE management.

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Waste electrical and electronic equipment is one of the essential pollutants with significant negative impacts on the environment and human health. In this study, a multi-period mixed-integer linear programming model is developed to design a closed loop supply network for the management of electrical and electronic equipment by explicitly considering the economic and environmental sustainability with a budget constraint. Different recycling options like refurbishing, disassembling, remanufacturing, and disposal centers are considered in the design of the network. The model minimizes the total costs of the network and the total carbon emission tax. The literature review shows that the introduced model is more comprehensive than the other existing models because it simultaneously determines the location of facilities, the capacity of facilities, type of manufacturing technologies, variety of vehicles, and the allocation and transportation of materials and products. The model was applied to a real-life case study in Iran and could provide a profit of IRR 245,509,165 M during the planning periods. The carbon tax policy with different echelons is applied to control the environmental impacts in which the carbon tax increases as carbon emissions increase. The results show a nearly linear relationship between the total costs of the network and the carbon tax. The carbon tax of equal to or more than 10,800 IRR/t CO2 can be a deterrent factor for the electrical and electronic equipment manufacturer in Iran to diminish emissions through investment in green technologies.

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With the growing use of electrical and electronic equipment (EEE), managing end-of-life EEE has become critical. Thus, the demand for sorting and detaching batteries from EEE in real time has increased. In this study, we investigated real-time object detection for sorting EEE, which using batteries, among numerous EEEs. To select products with batteries that have been mainly recycled, we crowd-sourced and gathered about 23,000 image datasets of the EEE with battery. Two learning techniques-data augmentation and transfer learning-were applied to resolve the limitations of the real-world data. We conducted YOLOv4-based experiments on the backbone and the resolution. Moreover, we defined this task as a binary classification problem; therefore, we recalculated the average precision (AP) scores from the network through postprocessing. We achieved battery-powered EEE detection scores of 90.1% and 84.5% at AP scores of 0.50 and 0.50-0.95, respectively. The results showed that this approach can provide practical and accurate information in the real world, hence encouraging the use of deep learning in the pre-sorting stage of the battery-powered EEE recycling industry.

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Modular connectors are applied by computer users, and they can be metallic secondary sources containing metals such as gold and copper. Because gold is a micro-component, the solution obtained after the pin digestion contains a low concentration of gold(III) ions, and efficient and selective sorbent should be used for gold(III) ion recovery. The selective removal of small amounts of gold(III) from 0.001-6 M hydrochloric acid solutions using pure and solvent-impregnated macroporous polystyrene crosslinked with divinylbenzene sorbents (Purolite MN 202 and Cyanex 272) is presented. Gold(III) ions were recovered effectively from the chloride solution after the digestion of the modular connector RJ 45 (8P8C) using Purolite MN 202 after the impregnation process. The dependence of the recovery percentage (R%) of gold(III) on the contact time was determined. The highest value of gold(III) ion sorption capacity (259.45 mg·g-1) was obtained in 0.001 M HCl for Purolite MN202 after the Cyanex 272 impregnation. The results can be applied to gold recovery from e-waste. The presented method of gold recovery does not generate nitrogen oxides and does not require the use of cyanides.

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Electronic waste (e-waste) is a growing waste stream. In Europe, e-waste is regulated by the Waste Electrical and Electronic Equipment (WEEE) Directive. Each manufacturer or importer is responsible for the end-of-life (EoL) treatment of the equipment it handles, although this task is usually outsourced to producer responsibility organizations (PROs) that collect and treat the e-waste. The WEEE regime has been criticized for focusing on waste handling according to the traditional linear economy, while, in a circular economy, the goal is to eliminate waste. Information sharing helps improve circularity, and digital technology is seen as enabling information transparency and visibility in the supply chain. However, there is need for empirical studies demonstrating the use of information in supply chains to improve circularity. We conducted a case study of a manufacturer, including its subsidiaries and PROs in eight European countries, in which we investigated the product lifecycle information flow related to e-waste. Our findings indicate that product lifecycle information is available, but that it is provided for purposes other than e-waste handling. Actors are willing to share this information, but it is not regarded as useful for EoL treatment since the actors involved in EoL handling believe that using this information could lead to delays and poorer performance in e-waste handling. Our findings contradict the optimistic view of digital technology as improving circularity in circular supply chain management. The findings further give reason to question the implementation of digital technology to improve the product lifecycle information flow as long as the involved actors do not request this information.

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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.

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The standardization of formal recycling and rational subsidy plays an important role in waste electrical and electronic equipment recycling. In order to explore the tripartite decision and evolution path of waste electrical and electronic equipment recycling in different time periods, a tripartite evolutionary game model consisting of recyclers, manufacturers, and government are presented. Moreover, the evolution stability strategies and conditions in each period are calculated by replicating the dynamic equation and Jacobian matrix. Numerical simulations on tripartite evolution stability strategies corresponding to different stages of industry development are used to verify the rationality of the model. The results indicate that there is existed an indirect effect between tripartite decisions, and the indirect effect can expand the slack of tripartite decisions' thresholds of waste electrical and electronic equipment recycling. The variable subsidy in waste electrical and electronic equipment recycling proposed in this paper is useful to incentive recyclers to choose a formal recycling strategy, and manufacturers also choose production with recycled materials as subsidy varies. Besides, the appropriate waste electrical and electronic equipment processing fee is a conducive indirect effect for the tripartite decision to the optimal evolutionary stability strategy in waste electrical and electronic equipment recycling and can promote manufacturers to produce with the recycled materials. The research can assist in benefit coordination and behavior adjustment of waste electrical and electronic equipment recycling members and provide a theoretical basis for the government to formulate appropriate recycling subsidies to promote the formal recycling of electronic waste recycling.

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In 2015-16, a study of approximately 500 waste plastic articles showed that portable X-ray fluorescence (XRF) was up to 95 % effective in screening for compliance with low persistent organic pollutant (POP) concentration limits (LPCLs) on brominated flame retardants (BFRs) in waste. The present study conducted in 2019-20 mirrors that conducted five years prior on a similar number and range of articles, testing the hypothesis that increased use of alternative BFRs as replacements for POP-BFRs will reduce the effectiveness of XRF as a tool for monitoring compliance with LPCLs. In comparing the results, the overall screening efficacy for LPCL compliance reduced from ~95 % to ~88 %, due in part to decreased prevalence of POP-BFRs and potentially increased presence of alternative flame retardants, particularly in goods with shorter lifecycles such as electronics. We additionally examined the impacts of a number of modifications to the XRF measurement protocol on its efficacy, including: using elemental Sb as a qualifier in detecting POP-BFRs in hard plastics; reduced XRF analysis time; and the elimination of background interference using a test stand. The rate at which hard plastics from electronic waste may be analysed by XRF can be substantially improved by reducing analysis time to 5 s, with minimal increase in false exceedances of the LPCL. Monitoring Sb does not appear an effective qualifier for the presence of POP-BFRs, as Sb seems to be used with a range of BFRs. Use of the test stand, while reducing interference, appeared to reduce accuracy when screening low density and thin samples. Despite a seeming increased use of alternative BFRs, screening of waste for compliance with LPCLs using rapid and low-cost screening methods such as portable XRF is still necessary as methods such as GC-MS cannot be scaled up to match the quantities of waste requiring screening.

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With the acceleration of the digitization process and the popularization of the internet, the recycling of waste from electrical and electronic equipment (WEEE) has become a potential and emerging recycling method. Stakeholders in the WEEE internet recycling industry have different roles which need to be clarified. The stakeholder structure and relationships, and stakeholder characteristics, lie at the core of recycling system governance. Therefore, it is necessary to identify stakeholders in the existing WEEE Internet recycling industry. This study selected 10 important stakeholders and classified them into key, potential, and marginal stakeholders using the Mitchell scale while analyzing their characteristics and interactions. The results showed that internet recycling companies, government, residents, and traditional recyclers are key stakeholders that are important for promoting the development of the industry. Based on the above analysis, policy advice is proposed to provide directions for the improvement of the WEEE industry.

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Waste electrical and electronic equipment (WEEE) which contains various valuable and harmful materials is an inevitable waste in modern society. In order to resolve the pollution problems associated with WEEE treatment, a WEEE management system has been established in China. The main role of importers and manufacturers of electrical and electronic equipment (EEE) is to pay the treatment fees to facilitate the WEEE recycling in China. The announced treatment and subsidy fee is given by set, not by the weight of WEEE. There is no lesser green treatment fee for the producers which can produce environmentally friendly EEE in China. Also, the recovery of refrigerants from the foaming agent of refrigerators is not required in China. In total, 45 million sets of recycled WEEE were certified in 2020, a year that contains the most updated data. Among them, 48%, 14%, 20%, 10% and 8% are for TV, refrigerator, washing machine, computer and air conditioners, respectively. The spatial analysis indicates that the WEEE recycling activities are mainly concentrated on the mid-east and east regions of China. It also can be concluded that the certified amount of each province has higher positive correlation with provincial population than provincial GDP per capita and green recovery rate. It also clearly notes that the amount of recycled air conditioner is the lowest for each province. Thus, more effort should be conducted to increase the recycling of scrapped air conditioner in China.