Waste Management & Research最新文献

The growing demand for new energy vehicles (NEVs) has resulted in a corresponding increase in demand for cobalt as a critical material. It is crucial to estimate the cobalt resource recycling potential of China's NEV industry to ensure a balance between the supply and demand for cobalt metal minerals. This article is based on using the historical data of the new energy passenger vehicle (NEPV) sales volume from 2013 to 2022 to estimate the NEPV sales volume from 2023 to 2035. On this basis, the Weibull distribution was used to analyse the different sales scenarios (low sales and high sales) of NEPVs in China, and the recycling potential of cobalt metal in NEPVs was evaluated under three battery life scenarios (8, 10 and 12 years) from 2023 to 2035. Based on the above scenarios, in 2035, the greatest recycling potential of cobalt is predicted to be 166.9 kilotonnes, with economic values of CNY 49.01-94.60 billion. Moreover, the extent to which the recycling potential of cobalt can cover the market demand for NEPVs was analysed. Our analysis concluded that recycling cobalt as a secondary supply has emerged as a necessary solution to supplement the primary supply, which can make a significant contribution to alleviating the pressure of the supply and demand.

This article examines a specific subtype of informal waste picking: deposit picking. Despite its global prevalence, waste picking has neither been extensively studied in the Nordic countries nor in the context of a deposit-refund system. Through interviews and text analyses of waste pickers in Stockholm, Sweden, similarities and differences between deposit picking and traditional waste picking are uncovered. For example, unlike other waste materials, the income from deposits is stable. The focus on beverage containers and the ability of reverse vending machines to sort the containers, lowers the knowledge threshold to begin the activity. The lightweight nature of beverage containers makes collection mobile, and deposit pickers often carry only a bag. The deposit pickers are mainly older, poor and male. Similar to traditional waste pickers, deposit pickers are central to the formal waste system, but their work is invisible, and foreign deposit pickers, in particular, are stigmatized. The dual invisibility of their labour and contributions, coupled with their independence from formal social systems, highlights the need for internal organization and representation within the formal systems.

The implementation of ecological compensation for cross-regional domestic waste treatment is beneficial for balancing the interests of waste generation districts and waste treatment districts. This paper introduces dynamic differential games to capture the temporal evolution and adjustment of strategies, examining dynamic game strategies under different compensation scenarios (non-horizontal ecological compensation, horizontal ecological compensation and fully shared ecological compensation). A new interest distribution model is proposed, with empirical analysis conducted using Shanghai as a case study to validate the reliability and feasibility of the model. The findings indicate: (1) Government intervention combined with horizontal ecological compensation significantly improves waste management efficiency and urban welfare. The compensation mechanism fosters regional cooperation, optimizes resource allocation, reduces decision-making conflicts and enhances overall processing effectiveness. (2) Without a compensation mechanism, high costs in export regions and low benefits in import regions result in low cooperation willingness. The ecological compensation mechanism enhances willingness to cooperate by fairly distributing costs and benefits, optimizing long-term cooperation and overall gains. (3) Complete shared ecological compensation is optimal, though partial shared mechanisms are also effective in practice. Proper interest and ecological compensation ratios can significantly improve waste management efficiency and urban environment, strengthening long-term cooperation. The study theoretically expands the dynamic optimization and cooperation mechanism analysis in waste management, provides solutions for environmental policy formulation in cross-regional waste handling and offers new perspectives and tools for addressing complex issues in cross-regional environmental governance, including targeted policy recommendations with practical significance for enhancing cross-regional waste management.

The aim of the present study is to highlight the effect of two commonly used plastics, polyethylene (PE) and polyethylene terephthalate (PET), on the quality and health indices of soil. To this end, a pot experiment was carried out using two soils, one acidic and one alkaline. The soil samples were collected from rural areas of central and Northern Greece and had similar particle size composition and almost equal copper (Cu), zinc (Zn), cadmium (Cd) and lead (Pb) concentrations. PE and PET microplastics (MPs) were added into the soil samples in two ratios (2% and 4% v/v) and remained in the soils for 20, 60 and 120 days. Then, the changes in the properties, nutrients, potentially toxic elements and health indicators of the soil samples were measured. PE addition at 4% v/v caused the maximum increase in trace element availability when it remained in the soil sample for 120 days. In contrast, PET addition caused a maximum decrease in the DTPA-extractable concentration of toxic elements (Cd and Pb), after 120 days of incubation in acid and alkaline soil. The present work provides a fresh perspective evaluating MPs from unwanted waste to materials with potential positive benefits, enhancing the circular economy approach to soil systems. Knowledge of the MPs present in soils, along with physicochemical soil properties, including their nutrient and toxic element content, are critical aspects that need to be addressed to ensure that soil quality and health are not adversely affected.

The management of end-of-life vehicles (ELVs) has become a significant environmental and economic challenge due to the substantial volumes of hazardous waste generated. This article analyses sustainable practices in ELV management across Europe, with a focus on contributions to the circular economy. The systematic literature review, conducted for articles published in the period 2016-2024, identifies five topics: (1) policy and regulatory frameworks evaluations and suggestions; (2) economic and environmental benefits through optimization modelling; (3) trends and performances analysis; (4) advanced treatment technologies and their impact and (5) economic and environmental impacts assessments. The findings highlight the importance of state-of-the-art recycling processes and coordinated stakeholder efforts in improving ELV management outcomes. In addition, the correlation between ELVs recycling and gross domestic product (GDP) was analysed. Data analysis for 27 European countries in the period 2016-2021 shows a moderate correlation. Specifically, countries with stronger economies tend to produce more ELVs, distinguishing two clusters when GDP is 35,000 € per capita. By adopting best practices and innovative approaches, European countries can enhance their ELV management systems, support a more circular economy and sustainable development. This work highlights the possible correlation between GDP per capita and ELV recycling rates across the European Union, the identification of economic clusters, and the critical role that advanced recycling technologies play in improving sustainability.

This article offers a reflective retrospective of the literature and practice on the informal waste and recycling sector. The authors have joined to share our experience and knowledge on the interface between the formal solid waste sector and informal recyclers and operators. Together, we discuss where this discourse has come from, where it is now, and where we, as practitioners, think it is going. We share our understanding of the waste and recycling sectors and how informality within them functions. The retrospective covers nearly 40 years of research, practice, advocacy, action, writing and intervention. The main storyline is how the public and private solid waste authorities and service providers relate to informal operators in both recycling ('the (private) value chains') and waste management ('the (public) service chain'). The recurring theme is how engaged scholarship and practice have interacted with, modified and improved the position of informal operators and workers and contributed to positive outcomes in both service and value chains. Throughout the period covered by this retrospective, opinions and framing on all sides have shifted substantially through the years, whereas the economic activities of informal recyclers and informal waste collection service providers have remained largely unchanged. Although we refer to both scientific and operational documents, we do not have the ambition to produce a scientific paper. Rather, we follow other authors of the special issue in referring to ourselves as involved witnesses who share a commitment to improving waste and recycling practices at the boundary of formal and informal systems.

The escalating volume of construction activities and resultant waste generation underscores the imperative for developing sophisticated segmentation models to facilitate efficient sorting and recycling processes. This study introduces WasteSAM, an enhanced iteration of the segment anything model (SAM), specifically tailored to address the intricate complexities inherent in construction waste imagery. Drawing upon a comprehensive dataset comprising over 15,000 masks representing five distinct categories of construction materials, WasteSAM exhibits notably superior segmentation capabilities. Quantitative analysis demonstrates significant performance improvements, with WasteSAM outperforming the original SAM model by an average of 23.9% in dice similarity coefficient and 30.0% in normalized surface distance metrics. The integration of stereo-image techniques in refining the training dataset has facilitated WasteSAM in more accurately discerning the three-dimensional structure of waste materials, thereby augmenting the precision of waste classification. Noteworthy is the model's adeptness in handling intricate textures and patterns across diverse imaging modalities, including varying lighting conditions and complex object interactions. While showing promising results, this study also highlights the need for high-quality, diverse datasets that reflect real-world construction site complexities, rather than merely larger datasets.

The complexity of risk assessment and the challenges in decision-making often impede the application of various models to renewable energy systems. This study introduces a comprehensive framework designed to streamline this process, facilitating informed decisions regarding the estimation of risks associated with solar photovoltaic (PV) technologies. Leveraging data and information available in the literature, the framework is particularly useful for manufacturers in selecting materials that balance low environmental risk with high efficiency. The framework emphasizes early-stage risk minimization by integrating changes during PV development, thereby promoting cleaner production systems. It's interconnected components encompass various approaches to risk assessment, control, and management, providing a structured methodology for risk reduction. Based on available information, the defined steps guide users through evaluating and mitigating risks. Applying risk minimization by metal substitution approach lowers the oral-ingestion and dermal-contact risk by a magnitude of four and six times, respectively. This framework will guide regulatory bodies throughout each step of the product life cycle, suggesting necessary changes and assessment strategies aligned with the perspectives of various stakeholders. By facilitating the identification and implementation of the most effective risk management strategies, the framework aims to advance the development of sustainable and safe PV technologies.

This study investigates, for the first time, the anaerobic digestion of food waste in Kuwait to optimize methane production through a combination of artificial neural network (ANN) modelling and continuous reactor experiments. The ANN model, utilizing eight hidden neurons and a 70-20-10 split for training, validation and testing sets, yielded mean squared error values of 0.0056, 0.0048 and 0.0059 and coefficient of determination (R²) values of 0.9942, 0.9986 and 0.9892, respectively. Methane percentages in biogas were predicted using six parameters: biomass type, pH, organic loading rate (OLR), hydraulic retention time (HRT), temperature and reactor volume. To validate the ANN results, continuous reactor experiments were conducted under an OLR of 3 kg VS m⁻³ d⁻¹ and HRT of 20 days at varying temperatures (35°C, 40°C, 45°C, 50°C and 55°C). The experiments demonstrated optimal methane production in the mesophilic range, with ANN predictions closely aligning with experimental data up to 45°C. However, deviations were observed at higher temperatures, particularly under thermophilic conditions beyond 50°C. This study provides novel insights into waste-to-energy initiatives in Kuwait and highlights the potential of integrating computational models with empirical data to enhance biogas production processes.

Piled smouldering has great potential for treatment and utilization of biomass wastes. However, its unsteady-state nature limits its industrial utilization, as well as treatment of smoke. This article addresses this issue by proposing the sequential operation of numerous smouldering chambers to realize steady- or quasi-steady-state piled smouldering. The superposition characteristics of sequential unsteady-state curves were analysed theoretically, and a code was developed to determine an appropriate number of piled chambers at an allowance oscillation percentage. Smouldering experiments were performed on a single mini chamber (length × width × height: 340 × 140 × 140 mm³) containing piled wood pellets mixed with wood powder. The superposition of sequential burning rate curves was demonstrated using the code based on the mass loss data of experiments. Analysis shows that the perfect-steady state is possible given the superposition value of the burning rate curve is a constant in this proposed system. Experiments show that the molar ratio of CO/CO₂ in smoke is almost a constant around 0.5 during densely piled smouldering, showing the great potential for self-sustained burning out the smoke. Based on the experimental results, the calculation results show that the relative oscillation range of burning rate (OSC) decreases from 75% to 3% while increasing the number of chambers from 2 to 7. This work provides a novel technology to enable quasi-steady-state smouldering for industrial utilization.