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Biodegradable plastics in single-use products have increased in popularity as a way to reduce the negative environmental impact of conventional plastics and meet the tightening law regulations. However, their recyclability needs to be assessed, as the environmental behavior of single-use plastics, even if compostable, is not negligible. Polylactide (PLA) is susceptible to thermal, oxidative, hydrolytic, and mechanical degradation during reprocessing, so the conditions of such cycles must be accurately controlled. The necessity of using additives to reduce such degradations during rotational molding, a process with long cycle times and oxidizing atmosphere, has been demonstrated. Chain extenders based on a carbodiimide (Bioadimide® 100 - KI), a methylene diphenyl diisocyanate (MDI), and a polystyrene-acrylic copolymer (Joncryl® ADR-4368c - J) have been added to post-consumer PLA wastes. It has been demonstrated that these three chain extenders enabled obtaining a higher molecular weight of the reprocessed polymer, compared to the ∼50% reduction for the neat PLA. The use of carbodiimide yielded the most similar performance to that of unprocessed raw material. All samples provided adequate thermal stability and processing parameters for the rotational molding. Carbodiimide is considered the most efficient additive, as it increases the molecular mass of the polymer as it remains unchanged after processing. Similarly, KI-modified PLA rheological behavior remains unchanged after processing, which means this compound can reduce thermooxidative and hydrolytic degradation reactions. Thus contributing to the achievement of improved processability and better performance; in particular, impact strength increased from 1.06 ± 0.56 for PLA to 8.12 ± 2.28 kJ/m2 for KI-modified PLA, and toughness of 5.36 ± 1.61 to 61.49 ± 8.01 J/mm3, respectively, leading to rotomolded items without structural defects. On the opposite, the use of Joncryl® and MDI led to structural defects in the rotomolded parts despite a higher molecular weight of the polymer, which resulted in poor mechanical properties, although better than PLA without any additive. All three chain extenders resulted in an amorphous PLA structure with increased glass transition temperature and improved thermal stability, which correlated with the reduced emissions of volatile compounds compared to neat recycled PLA. The presented findings significantly contribute to a better understanding of PLA and its modifications at a molecular scale required for its efficient and possibly environmentally burden-free reprocessing. Gathered knowledge will be crucial for optimizing its environmental performance and widening its applications, particularly in a process with long cycle times and oxidative character, such as rotational molding. [ABSTRACT FROM AUTHOR]

While the Circular Economy predominantly affects large companies and multinationals, its impact on Small and Medium-sized Enterprises (SMEs) is an emerging research area. This research aimed to unfold the Circular Economy strategies implemented by SMEs within an industrial cluster context. Ten companies from the Italian tanning cluster of Arzignano were selected as case studies. Thematic analysis, pattern-matching, and multi-value Qualitative Comparative Analysis techniques were used to analyze primary and secondary data. Main findings revealed that CE strategies taken by the studied companies were characterized by the economic and efficiency benefits provided, such as resource-saving, waste management, energy use reduction, and materials selection for further recycling. SMEs' management is targeting compliance with environmental regulations/certifications, market pressures, and cost-benefit assessments, evidencing an adaptive behavior to external exigencies. Novel findings came from the meso level, such as a 'symbiotic circularity' strategy taken by two SMEs and their value chain for co-production, and the chain actions related to recycling, remanufacturing, and reusing wasted products by partner companies. A cascade chain of interdependent actions toward Circular Economy practices was also identified within the cluster level. Reactive and proactive Circular Economy strategies were identified in a multilevel framework. [Display omitted] • Circular Economy at the meso-level (industrial clusters) needs further development. • Proactive/reactive strategies were identified at individual/collective dimensions. • Common Circular Economy action among SMEs is reducing. • Common Circular Economy action within the cluster is wastewater recycling. • The notion of symbiotic circularity actions is introduced. [ABSTRACT FROM AUTHOR]

Silica aerogels are excellent insulation materials, but they possess high embedded costs and their production includes many energy-intensive steps. A novel protocol developed to produce silica aerogel from waste soda lime glass via ambient pressure drying was assessed regarding sustainability. Upcycling waste materials and implementing a low-energy drying technique are aimed at increasing the sustainability of aerogels. This study presents a cradle-to-gate life cycle assessment (LCA) of this process on a laboratory scale (reactor volume of 0.5 l) as well as on a modeled industrial scale (reactor volumes of 100 l and 1000 l). The environmental impacts associated with each scale, as well as with each step of the production, were calculated and summarized with an environmental cost indicator in euros for each process. Potential end-of-life scenarios were considered to explore waste treatment approaches. Results show that electricity consumption is a major contributor to environmental impact, especially at the laboratory scale. However, at the industrial scale, efficiency is significantly improved, thereby drastically decreasing the impact of electricity. Additionally, the contributions of raw materials have a larger environmental impact than those of waste disposal, indicating that it is crucial to focus on the reduction and re-usage of reactants and solvents. • The environmental impacts of silica aerogel from waste glass are investigated with LCA. • Aerogel was produced via the ambient pressure drying method. • An industrial plant is modeled to assess differences between production scales. • Major contributors: electricity for lab scale, raw materials for industrial scale. • Kg CO 2 eq were 428 (lab, 0.5l) and 34 (upscaled, 100l) per kg of aerogel. [ABSTRACT FROM AUTHOR]

Livestock manure is commonly utilized as a fertilizer in agricultural system, potentially resulting in the dissemination of antibiotic resistance genes (ARGs) to plants. This raises concerns about the efficiency of manure treatment methods in reducing ARGs. Although sterilization treatment is frequently applied to mitigate the microbial loads, its efficacy in reducing ARGs remains unclear. This study investigated the impact of sterilized vs. unsterilized manure on the profiles of ARGs and bacterial community in a hydroponic lettuce system. After the 20-day cultivation period, 68 ARGs and 18 mobile genetic elements (MGEs) were identified. Manure sterilization not only promoted lettuce growth but also resulted in a reduction of ARG and MGE subtypes by 50.00%–86.21% in lettuce endophytes. Proteobacteria, Bacteroidota, and Firmicute were the dominant phyla, with a notable reduction of 70.05%–99.01% in Firmicutes by sterilization in lettuce endophytes. The predominant human pathogenic bacteria genera were Pseudomonas , Sphingomonas , and Bacillus , and sterilization effectively reduced the presence of Bacillus. Moreover, the estimated intake of ARGs in leaf endophytes ranged from 2.88 × 105 to 9.16 × 108 copies per day, including 6 high-risk ARGs. Manure sterilization reduced the association between high-risk ARGs and human pathogenic bacteria. The interaction between bacterial community and MGEs shaped ARG patterns with a contribution of 81.87%. Overall, these findings highlighted the critical role of sterilization in reducing ARGs in the manure used for hydroponic agriculture, providing guidance in waste management, crop safety, and public health. [Display omitted] • Manure sterilization reduced 50.00%–86.21% of ARGs and MGEs in lettuce endophytes. • Manure sterilization reduced 70.05%–99.01% of Firmicutes in lettuce endophytes. • Manure sterilization reduced 99.32% of Bacillus in root endophytes, a major HPB. • Sterilization preserved nutrients in the manure and promoted the lettuce growth. [ABSTRACT FROM AUTHOR]

Market growth for biogas solutions is important for climate change mitigation since it enables both effective waste management and a reduction of fossil fuel use. The aim of this paper is twofold. First, based on a discussion on previous research, a categorization of barriers to market growth in biogas solutions is developed. Second, the categorization is used to identify and analyze barriers within the Swedish market. The results show that market growth in Sweden has been reduced by the presence of multiple barriers such as regulatory uncertainties related to taxes and public policy instruments, lack of public funding, lengthy permit and planning processes, increased competition from electrification, lack of communication about biogas benefits, lobbying against biofuels, too high a price on biogas, and fierce competition from fossil fuels. The paper concludes with a discussion of contributions and the managerial and policy implications. • Develops a categorization of barriers to market growth in biogas solutions. • Presents key market actors involved in the respective categories of barriers. • Uses the categorization to identify and analyze barriers in Sweden. • The results show that multiple barriers to market growth exist in Sweden. [ABSTRACT FROM AUTHOR]

This study investigates the impact of implementing the pay-as-you-throw policy as a fiscal incentive mechanism for municipal waste management across municipalities in the Emilia-Romagna region, Italy. Utilizing panel data from 2010 to 2022 and employing a synthetic control with staggered treatment adoption, we evaluate the policy's effects on environmental and local public finance performances. Our findings reveal that treated municipalities witness an average 10% increase in separate waste collection alongside a parallel reduction in municipal waste production since the policy outset, equating to approximately 60 kg per capita annually. Furthermore, our analysis indicates that the policy enables local governments to reduce current energy and environmental expenditures by roughly €130 per capita annually in our optimal model. Notably, results hold robust across three recently developed estimators using difference-in-differences with staggered treatment adoption over time. The policy proves overall effectiveness in promoting circularity within municipal waste management systems, leading to better environmental performances, and decreased environmental management expenses. These implications underscore the potential value for local governments to adopt similar strategies where not yet envisaged. [ABSTRACT FROM AUTHOR]

In the coming decades, the failure and expiration of over 100,000 landfills involving billions of tons of waste not only threaten global water security but also lead to a sudden increase in the global demand for solid waste disposal. Therefore, further research is needed on the ways in which landfill performance is degraded, their life expectancy, the factors that influence them and the ways in which they are influenced. A study estimated the performance degradation and expected lifespan of a modern hazardous waste landfill in China. The landfill experienced slow performance degradation in early years (0–12 years). But during mid-term (12–62 years) due to the rapid degradation of the liner material, the rate of leakage from the containment layer will increase by a factor of 4.8–27.1, leading to its earliest failure after about 38 years. This indicates the need for measures to prevent rapid performance degradation in the middle of the landfill's service life and to strengthen monitoring of performance indicators and environmental medium pollution in the later period (after 62 years) to respond to potential scrapping and pollutant leakage problems. Differences in construction quality and regional climate can cause differences in the lifespan of landfill facilities by up to 20 and 30 times, highlighting the importance of scenario-based failure and lifespan prediction for designing reasonable monitoring plans and preparing response measures to prevent potential groundwater pollution and to meet the sudden increase in demand for secondary waste disposal. [ABSTRACT FROM AUTHOR]

This study explores a novel integration of electro-physicochemical technologies to generate energy and treat water from combined food waste (FW) and blackwater (FW-BW), with BW containing waste activated sludge with simulated flush water. The FW-BW substrate was gravity-separated and pretreated with hydrodynamic cavitation (HDC). Solids from gravity separation were used for energy generation via anaerobic digestion (AD) alone or integrated with microbial electrolysis cells (AD-MEC). HDC pretreatment had 51.6% more CH 4 production in 5 days (266 mL CH 4 /g VS) and 63% more in 30 days compared to AD without HDC. The CH 4 production after 5 days of digestion with HDC pretreatment (266 mL CH 4 /g VS) was similar to the amount produced without HDC over 30 days (263 mL CH 4 /g VS). Using MEC increased CH 4 production by 12.7% compared to AD-only. The liquids from gravity separation were treated with electrocoagulation (EC) at 15 V (90 min), which removed 96.2% of the chemical oxygen demand (COD) and 100% of the total suspended solids. The pilot scale design indicates that the AD-MEC and EC units would generate 1.4 times more energy than energy consumed through applying these novel technologies. These findings demonstration the applications of four technologies (HDC, AD, MEC, and EC) in an energy-efficient waste management approach, producing bioenergy and cleaner water for low-tier use, especially in areas lacking traditional waste treatment options. [Display omitted] • Novel technologies for energy and water treatment of food waste + blackwater. • HDC pretreatment had 51.6% more CH 4 production in 5 days than AD-only. • AD-MEC integration increased energy production by 12.7% compared AD-only. • Electrocoagulation at 15 V for 90 min removed 96.2% COD and 100% of solids. • A pilot scale AD-MEC design showed 1.4x more energy generated than energy input. [ABSTRACT FROM AUTHOR]

This study evaluates the environmental impacts associated with the conversion of garden organic waste into value-added products, namely compost or biochar, employing various processes. Three distinct scenarios are considered: composting garden organic waste followed by screening of oversized materials (CBP), pyrolysis of oversized screenings of compost into biochar AP(I), and in-situ conversion of garden organics into biochar AP(II). A comprehensive Life Cycle Assessment (LCA) was conducted using OpenLCA software and life cycle impact assessment was conducted using Recipe 2016 midpoint methodology. The environmental ramifications of each scenario were assessed, optimising transport distances in AP(II) to achieve a functional unit of one tonne of biochar produced within a cradle-to-gate system boundary. For the first time, this study offers a holistic exploration of the benefits of soil biochar application, extending its scope to climate change mitigation, incorporating the optimisation of transport distance and its influence when scaling up the technology. The results revealed that global warming was increased from 125 kgCO 2 eq during composting of garden waste to 232 kgCO 2 eq where oversized screenings of compost is converted to biochar at an off-site facility. However, direct conversion of the oversized organic waste to biochar, without composting, showed reduced global warming impact of 56 kgCO 2 eq, and is thus the most favourable scenario to limit climate impacts of this fraction of organic garden waste. However, among 18 environmental impact indicators studied, eight indicators were either not influenced or did not significantly increase by transport distance to an off-site pyrolysis facility, while the magnitude of 10 impact indicators increased with transport distance. The insights and methodologies presented in this study hold global relevance, based on an actual case study in regional Australia, offering valuable recommendations for sustainable waste management practices and establishing biochar as a carbon-neutral or carbon-negative solution. The findings contribute to existing waste management knowledge and provide guidance for accessible carbon dioxide removal and soil carbon sequestration technologies. [Display omitted] • A comprehensive LCA for valorisation of garden organics was conducted. • Direct conversion of garden organics to biochar showed least potential environmental impacts. • Biochar provides opportunities for avoided, reduced, and removed carbon from atmosphere. • Maximum transport distance has been identified for individual impact categories. [ABSTRACT FROM AUTHOR]

Rapid industrialization and urbanization drive China's massive urban household solid waste (HSW) generation. Classification and resource recycling of HSW is an effective way to address the "garbage-sieged city" dilemma and promote "urban mineral resources" exploitation. Despite efforts since 2000, HSW sorting and recycling remain at 30%. This study develops a multi-agent based behavior simulation model for HSW classification and recycling, incorporating the interactions and decision-making of key agents, including residents, enterprises, and the government. Taking Suzhou, China as a case study, field surveys were conducted, and behavioral decision-making functions were constructed to simulate micro-behavioral responses and macro-system evolution under different policy incentives, and to predict the implementation effect of domestic waste management approaches, provides the basis for decision-making. The results demonstrate that a combination of waste metering charges, recycling subsidies, and enhanced education program can effectively regulate agent behavior and optimize the system. One year after the implementation of the simulation, the number of "unclassification" residents has dropped from 1.85 million to 250,000 decreased by 86%; the number of "classification deposition" residents has declined from 1.28 million to 1.08 million, reduced by 16%; the number of "selling after classification" residents has risen from 1.05 million to 2.81 million, increased by 63%; the daily waste output per capita has decreased from 1.21 kg to 1.04 kg, reduced by 14%; the recovery rate of resources has been raised from 33.4% to 66.5%. The implementation effects of other policy scenarios are ranked as follows: the metering charge > the recycling subsides > the enhanced education program. The findings provide a basis for decision-making in HSW management. Concerning the metering charge and the recycling subsidies, they can benefit positive interactions encouraged by such economic stimulus. At the same time, it is suggested to strengthen classification and recycling infrastructure, and push forward the integration of HSW classification recycling. • A multi-agent based behavior simulation model for household solid waste recycling is developed. • Behavioral decision-making functions were constructed taking Suzhou as a case study. • The implementation effects of four policy scenarios were dynamically evaluated using the model. • Ways and policy suggestions on promoting classification of HSW in China are proposed. [ABSTRACT FROM AUTHOR]

Clean production and the ecological transition pose significant challenges for international space organizations, which are developing new strategies for recycling space waste products within a circular economy model. Successful recycling initiatives, which could encompass all or only parts of space waste management, would facilitate the reuse of materials that would otherwise be discarded. The present study aimed at testing a method for the identification and categorization of space waste to facilitate the definition of effective sorting and recycling operations in space. In more detail, the study investigated the potential of a sustainable, low-cost method based on hyperspectral imaging (HSI), employing HSI sensors operating in two spectral ranges—shortwave infrared (SWIR) and near-infrared (NIR)—to develop a classification model capable of identifying and sorting space waste for recycling. The findings demonstrate the advantages of using HSI techniques to identify, recognize, and classify various materials, thereby presenting a viable approach aligned with the circular model. Moreover, the proposed approach is non-invasive and non-destructive, eliminating the need for chemicals that could harm the environment. The technique may enable the differentiation of potentially valuable space waste from pollutants, contributing to sustainable waste management and the circular economy. [ABSTRACT FROM AUTHOR]

Environmental sustainability has emerged as a crucial aspect for every business, as the wastage of used products greatly contributes to greenhouse gas emissions and environmental hazards. Adopting the circular economy concept is essential to address this problem. This approach prioritizes reliability and re-manufacturability, aiming to simultaneously reduce waste and enhance sustainability and profitability. In this context, the proposed model introduces a sustainable closed-loop supply chain model wherein the manufacturer oversees the production process and delivers requested batches to the retailer under the single order and multi-shipment policy. The model incorporates the notion of circularity, quantified by a circularity index representing the degree to which the product's circularity level. The level of product circularity can be enhanced by material choice, supplier selection, and innovative design while manufacturing. The model being presented aims to maximize the total integrated profit of the closed-loop supply chain system by optimizing the number of shipments as well as the circularity index. It is evident from the analysis that the circularity index significantly influences profits and environmental sustainability by increasing product demand and extending product life cycles. Notably, the numerical example provided in the model illustrates that accounting for the effects of the circularity index results in an optimal profit up to 5% higher compared to scenarios where such effects are not considered. • A CLSC model incorporating a multi-shipment policy for circular products has been formulated. • Model determines the circular economy index within a CLSC system. • Product's demand and price are assumed to be influenced by the circularity index. • Efficient waste management and increased overall profit are achieved through the inclusion of remanufacturing for used items. [ABSTRACT FROM AUTHOR]

Bromine resources, widely utilized in basic chemical engineering, are considered non-renewable. A substantial amount of Bromine-Rich Saline Wastewater (BRSW), a hazardous waste, is generated during the smelting process of waste printed circuit boards (WPCBs). The efficient conversion of bromine resources is important in BRSW, which contain high concentrations of bromide ions. This study developed a synergistic treatment method utilizing electrolytic manganese anode sludge (EMAS) achieved efficient conversion of Br− to Br 2 in BRSW. Optimal technical parameters are determined through single-factor experiments, and the oxidative acid leaching process was optimized using response surface methodology (RSM). The significant influencing factors for Br− conversion were ranked as acidity > anode mud addition amount > temperature > time, resulting in a bromine conversion efficiency of 96.55%. Kinetic studies of bromine conversion in BRSW during the oxidation-acid leaching process indicated a two-stage process: Stage I being a chemical reaction control model and Stage II being a diffusion control model. The reaction mechanism was elucidated, where H+ initially breaks the Mn-O bond in MnO 2 , exposing O vacancies and forming Mn4+, leading to a redox reaction between free Br− and Mn4+. This research embodies the concept of synergistic solid waste disposal, achieving cost-effectiveness and streamlined preparation of bromine, and providing technical and theoretical support for bromine resource recovery in BRSW. This study embodies the concept of synergistic disposal of solid waste, achieving low-cost and short-process preparation of bromine, and elucidates the kinetics and reaction pathways of the oxidative acid leaching process, with a bromine conversion efficiency as high as 96.36%. The reaction mechanism is clarified, where H+ first breaks the Mn-O bonds in MnO 2 , exposing O vacancies and forming Mn4+, followed by a redox reaction between free Br and Mn4+. [Display omitted] • Utilizing synergistic solid waste disposal yields good economic feasibility. • Realizing short-process conversion of bromine in bromine-rich saline wastewater. • The bromine conversion mechanism was elucidated. [ABSTRACT FROM AUTHOR]

Recycling in apartments has been problematised around the world, as this housing typology is associated with relatively low resource recovery rates. Rather that assuming that occupant behaviours are the key concern, this paper starts with the observation that apartments are sites of unevenly distributed spatialities and responsibilities. They co-shape material and infrastructural affordances and call upon diverse knowledge of waste management in collective and shared arrangements. This paper analyses data from an in-depth qualitative study involving apartment waste and apartment households in Melbourne, Australia. It shows that boundaries and boundary objects help define waste and its relationships, mutually shaping and being shaped by material flows and reconfiguring responsibilities. The co-production of these boundaries and boundary objects is correlated to mechanisms of governance, regulations, assumptions associated with verticality/shared living, and seasonality. In the context of post-consumer waste recovery policy ambitions, the paper illustrates how a) shifting boundaries to redistribute responsibility b) engaging with somatic work to bridge boundaries that challenge material flows, and c) harnessing boundaries that nurture and normalize sustainable waste practices, can be potential sites of intervention. As a theoretical contribution, it draws upon boundary work and social practices as a novel way to inform interventions to promote sustainability. • Boundaries define waste and its relationships, mutually shaping material flows. • Boundaries are produced through social practices. • Co-production of boundaries relates to governance and assumptions about apartments. • Harnessing boundaries that normalize sustainable waste practices is required. [ABSTRACT FROM AUTHOR]

An increasing number of electric vehicle batteries will reach the end of their life cycle with the fast growth of electric vehicles. Since the recycling of retired electric vehicles batteries is of great significance in the light of resource utilization, ecological protection, energy saving and economic benefits, the proper management of electric vehicle battery recycling (EVBR) is crucial for achieving sustainable development. However, due to the involvement of multiple stakeholders, there are many potential barriers in the process of EVBR, and analyzing these barriers can significantly help the recycling management of waste electric vehicle batteries towards a circular economy. Although the literature has focused on analyzing obstacles to implementing reverse logistics for electric vehicle lithium battery recycling from a manufacturer's perspective, less attention has been paid to analyzing barriers to EVBR from a multi-stakeholder perspective. This paper thus aims to investigate the barriers to EVBR from a multi-stakeholder point of view, identify the main barriers affecting battery recycling, and analyze the interrelationships and hierarchies between these barriers. Based on expert opinions and literature reviews, this paper identifies twenty major barriers to EVBR and uses interpretive structural modelling (ISM) method to determine the interrelationships and hierarchies between the barriers, and finally classifies the barriers to EVBR into a seven-level structural model. Furthermore, matriced impacts corises-multiplcation appliance classement (MICMAC) analysis is applied to categorize the identified barriers to EVBR, and the twenty barriers are finally classified into three categories, namely dependent barriers, linkage barriers, and driver barriers. This paper discusses theoretical insights, managerial and practical implications, and measures to overcome EVBR barriers based on the results, which show that the lack of more appropriate incentives is a major barrier to EVBR implementation. This paper provides a solid theoretical foundation for the further development of battery recycling policies, and will also help relevant stakeholders and governments to better understand these barriers and adopt effective approaches to address them. [Display omitted] • This paper studies the barriers to electric vehicle battery recycling. • A hierarchy of potential electric vehicle battery recycling barriers is identified. • Measures to overcome the barriers to electric vehicle battery recycling are given. • Several key theoretical implications and managerial insights are provided. [ABSTRACT FROM AUTHOR]

Pyrolysis of non-recycled municipal plastic waste has the potential to mitigate the plastic waste crisis and to produce transport fuels (diesel or hydrogen), as compared with the conventional methods such as incineration or landfilling that have potential adverse environmental consequences. Transport fuel production from non-recycled municipal plastic waste contributes to the transition to more sustainable waste management. However, little is known about the influences of system scales and end product selection on the carbon footprints of the plastic waste treatment. Here, we applied the approach of life cycle assessment to compare the carbon-saving potential of centralized, large-scale and decentralized, small-scale pyrolysis systems producing diesel and hydrogen in the United Kingdom. It is shown that centralized systems had a lower global warming potential results than decentralized systems despite their greater transportation distances. The global warming potentials of diesel production for centralized and decentralized systems were 801 and 1345 kg CO 2 -eq. per tonne of non-recycled municipal plastic waste, respectively, whilst hydrogen production had much higher global warming potentials which are 7110 and 7990 kg CO 2 -eq per tonne of non-recycled municipal plastic waste, respectively. In hydrogen-producing systems, crude carbon nanotubes are also produced, and the purification process of carbon nanotubes requires significant material resource (hydrochloric acid and deionized water) inputs, resulting in high Scope 2 and 3 emissions. Also, it is worth noting that the global warming potential related to the Scope 1 emissions for the diesel-producing systems exceeds 80%, whereas the hydrogen-producing systems yield opposite results. The end use of diesel produced has a greater carbon footprint than the end use of hydrogen. The carbon saving from the displacement of fossil hydrogen was two times higher than that from diesel displacement. Decentralized, small-scale hydrogen production from plastic waste had the highest global warming potential among all as the conversion process of municipal plastic waste to hydrogen and carbon nanotubes for small-scale systems is more energy and resource intensive. Sensitivity analysis showed that various factors, such as feedstock composition and the heating energy consumption in the conversion process, had less influence on the global warming potential of centralized systems as compared to decentralized systems. [Display omitted] [ABSTRACT FROM AUTHOR]

Adopting net zero neighborhoods (NZN) combined with circular economy are increasingly recognized as an essential strategy for construction companies, allowing their transition towards sustainability and contributing to climate change mitigation. Transforming existing neighborhoods into NZN is necessary to achieve energy self-sufficiency and net zero by 2050. The success of NZN hinges on government initiatives. However, existing studies appear to lack a comprehensive exploration of the transformation initiatives within NZN, spanning aspects like raw materials, construction practices, transportation, and waste management, particularly in terms of technological advancements. To address the gap, this research introduces a conceptual framework that integrates the multiple case studies design method with an urban transformative capacity model. This innovative framework is the first application of a multi-level urban transformative capacity model in transforming existing neighborhoods into NZN within a specific region. This research specifically utilizes South Wales in the UK as a case study. It identified four key initiatives in technology, construction, transportation, and waste management. These initiatives offer significant benefits, including fostering a more sustainable and environmentally friendly construction industry through enhanced traceability and efficiency, and simultaneously promoting social sustainability by improving community engagement, providing social benefits through sharing economy initiatives, and creating new green job opportunities. [Display omitted] • This study aims to apply CE principles to create net zero neighborhoods. • A conceptual framework is proposed for transforming existing neighborhoods into NZN. • The method integrates multiple case studies and urban transformative capacity model. • This research uses South Wales in the United Kingdom as a case study. • The innovative initiatives can drive successful transformations in the target city. [ABSTRACT FROM AUTHOR]

Achieving universal access to clean water, as mandated by SDG 6 – Clean Water and Sanitation, is crucial for supporting human health and environmental sustainability. Water treatment plants generate a by-product known as Water Treatment Plant Sludge (WTPS), comprising organic and inorganic substances. Traditionally, the disposal of WTPS poses environmental risks, including nutrient runoff and heavy metal contamination. This study investigates using centrifuged WTPS, without prior treatment, as an adsorbent to remove contaminants from treated wastewater, offering a sustainable waste management solution. Through comprehensive characterization using Scanning Electron Microscopy, Thermogravimetric Analysis, Fourier Transform Infrared Spectroscopy, and geo-environmental parameter assessment, the research evaluates the adsorption efficacy of WTPS. A factorial design methodology facilitated the systematic examination of adsorption tests. Findings indicate that WTPS exhibits adsorption capacities for phosphorus (q = 0.2 mg g-1), Chemical Oxygen Demand (q = 1.1 mg g-1), and metals under specific conditions. Maximum removal efficiencies for total coliforms and Escherichia coli were achieved with extended contact times, showcasing WTPS's potential as a robust adsorbent. The research demonstrates that centrifuged WTPS can significantly reduce concentrations of metals such as Pb, Co, and Ni (100%), Al (96%), Cu (95%), and Fe (93%) in treated wastewater, presenting a promising approach for enhancing wastewater quality. However, the interaction between WTPS and wastewater resulted in an increased concentration of Mn in the effluent, highlighting the complex dynamics of adsorption processes. In conclusion, centrifuged WTPS emerges as a viable, cost-effective adsorbent, aligning with sustainable waste management practices and circular economy principles. [ABSTRACT FROM AUTHOR]

Over the past century, the world has grappled with the looming challenge of climate change, with the construction sector emerging as a significant greenhouse gas emitter. This research aims to estimate greenhouse gas (GHG) emissions, cumulative energy demand (CED), and associated disposal costs by applying life cycle assessment (LCA) principles to the disposal of construction materials in northern Thailand. The study employs LCA as the analytical method, focusing on the disposal of concrete, steel, and wood waste from residential construction projects. The life cycle inventory analysis investigates waste management practices, including on-site landfilling, recycling, and transportation with an average distance of 30 km. The findings reveal that concrete waste is the primary contributor, with transportation playing a pivotal role. In the conventional case, total GHG emissions reach 38.624 kgCO 2 eq/m2, with CED at 12.991 MJ/m2 and disposal costs totaling 420.97 THB/m2. Three waste management scenarios are explored: Scenario 1 (50% on-site landfilling, 50% reuse/recycling), Scenario 2 (75% on-site landfilling, 25% transportation landfill), and Scenario 3 (100% on-site concrete landfilling, 100% steel reuse/recycling, 100% wood waste landfilling). Scenario 3 shows a significant 20.3% reduction in GHG emissions, a 90.5% decrease in CED, and a disposal cost reduction of 20.9% compared to the conventional case. This study underscores the importance of strategic waste management decisions, highlighting the potential of sustainable practices to foster an eco-friendly construction sector. Its findings offer valuable insights and recommendations, advocating for refined strategies like prioritizing recycling, optimizing transportation, and minimizing incineration to effectively reduce emissions and promote environmental responsibility in construction. [Display omitted] • Thorough examination of construction waste management practices, focusing on concrete, steel, and wood materials. • Concrete identified as the primary contributor to greenhouse gas emissions, highlighting its significant environmental impact. • Exploration of three waste management scenarios, revealing substantial emission reductions and energy conservation potential. • Comparative analysis identifies strategies to optimize environmental impact and energy efficiency, particularly in wood waste management. • Refined strategies proposed, including recycling prioritization and transportation optimization, to effectively mitigate emissions and promote sustainability. [ABSTRACT FROM AUTHOR]

Repurposing of food waste (FW) affords an alternate waste management strategy and sustainable product yield. Thus, this study proposed an integrated biorefinery approach, repurposing pretreated FW hydrolysate for microalgae cultivation and utilizing residual solids for biomethane recovery. FW biomass with different solubilization ranging from (10–15 to 60–65%) obtained during surfactant coupled disperser pretreatment was used as a substrate for microalgae (Chlorella vulgaris) cultivation. A higher microalgae biomass productivity of 0.87 ± 0.003 g/g substrate was obtained from the FW hydrolysate with 40–45% solubilization. The microalgae cultivated in FW hydrolysate with 40–45% solubilization yielded a higher protein, carbohydrate, and lipid accumulation of 380 ± 20 mg/g, 480 ± 30 mg/g and 360 ± 15 mg/g. Besides, the methanogenesis process showed a higher methane yield of 0.294 ± 0.003 L/g COD utilizing residual solids of pretreated food waste as substrate. This integrated biorefinery provides a sustainable platform for completely valorizing food waste biomass and recovery of multiple products. [Display omitted] • Repurposing of food waste is an alternate sustainable waste management strategy. • Algal biomass of 0.87 ± 0.003 g/g was obtained from 40 to 45% solubilized food waste. • More biopolymer was noted in microalgae cultivated in 40–45% solubilized food waste. • Higher methane of 0.294 ± 0.003 L/g COD was obtained in 40–45% solubilized residues. [ABSTRACT FROM AUTHOR]

With the advancement of socio-economic development and the growing emphasis on environmental consciousness, electronic waste (e-waste) with hazardous properties has emerged as a focal point in global waste management. Waste printed circuit boards (WPCBs), which contain abundant metal elements such as Au, Ag, Cu, Al, Fe, and rare earth metals, have garnered widespread attention regarding the recycling challenges. In the absence of policy guidance and feasible technological advancements, WPCBs are typically disposed of through landfilling or incineration. However, WPCBs not only encompass economically valuable metals that can be extracted and processed but also harbor significant amounts of heavy metals and harmful substances that pose severe threats to both human health and environment. Therefore, the clean recycling of WPCBs is pivotal for fostering sustainable development in our society. This paper provides a comprehensive overview of the treatment methods for WPCBs. Firstly, the resource and environmental threat posed by WPCBs is introduced to illustrate the urgency of WPCBs recovery. Subsequently, the approaches for pre-treatment and pre-concentration of WPCBs recovery are described, along with an elaboration on their potential for development. The pre-treatment methods primarily involve crushing and grinding, while pre-concentration mainly utilizes physical techniques such as gravity separation and flotation based on particle density and surface properties. Thirdly, the deep purification methods for WPCBs metals are discussed, including pyrometallurgy, chemical treatment, and biological metallurgy; particular emphasis is placed on the application of bioleaching technology with sustainable development potential. Furthermore, the reuse methods for metallic components (MCs) and non-metallic components (NMCs) obtained through WPCBs separation are summarized. Finally, a systematic process for the clean and efficient recovery of WPCBs is proposed that encompasses pre-treatment, pre-concentration, biological leaching, and all components utilization, aiming to achieve sustainable resource utilization. [ABSTRACT FROM AUTHOR]

Photovoltaic (PV) technologies in the energy industry are crucial for transitioning to a decarbonized era that relies on renewable energy sources. This systematic review aimed to identify the potential environmental impacts associated with the entire life cycle of PV technologies. To accomplish this, the review analysed literature from the last five years focused on life cycle assessment and evaluating PV technologies' environmental impacts/toxicity. In total, 72 final articles were collected and analysed, considering the year of publication, research methodology, and geographical context. Although there is substantial knowledge regarding potential impacts associated with end-of-life (EoL) PV technologies, only a limited number of regions have specific regulations regarding PV waste. With the incorporation of circular economy principles, targeted strategies for EoL treatments can be developed and implemented, leading to a substantial reduction in the environmental impacts caused by EoL PV modules, where this aspect represents a critical concern within the context of PV technologies. Therefore, this study emphasises the need to integrate life cycle assessment, circular economy, and systems thinking to achieve more sustainable development when utilizing PV technologies so that the diffusion of PV technologies helps decarbonization transitions without creating major unintended environmental problems in waste systems. • Photovoltaics results in different environmental impacts across their entire life cycle. • End-of-life phase of photovoltaics results in significant environmental impacts. • Most nations lack in specific regulations for end-of-life treatment of photovoltaics. • Circular economy principles are imperative in the utilization of photovoltaics. [ABSTRACT FROM AUTHOR]

Digitalization and circular economy (CE) principles are crucial to 21st century organizations, wherein the management approach can function as a strategic lever. The main gap in the field is related to the position of digitalization in the waste management process, with a concentration on soft computing approaches in developed and developing countries. Actually, the steps of digitalization implementation in the waste management supply chain are evaluated in this research item as a review study. This study uses VOS viewer to analyze scientometrics to examine digitalization in waste management. The article pioneer's simulation methods showcasing digitalization and the circular economy in waste management. Digital technology fosters CE goals, vital for sustainable waste practices. In the subsequent discourse, an examination of the ramifications engendered by the process of digitalization for both the environment and the economy within the framework of the CE is presented. The fourth component of this comprehensive review develops simulation methods to demonstrate digitalization in waste management. The results of this research demonstrated that digitalization integrates Internet of Things (IoT). sensors, optimizes waste management efficiency, and aids decision-making. Route optimization and energy efficiency enhance sustainability in waste management. [Display omitted] • Systematic review of digitalization in waste management: Circular Economy aspect. • MATLAB simulation for waste reduction strategy analysis. • Statistical evaluation: Market size analysis for digitalization in waste management. • Energy management via digitalization simulation in waste processing. [ABSTRACT FROM AUTHOR]

The agricultural sector in Thailand contributes to air pollution, due to the practice of open burning of agricultural wastes. An in depth-analysis of regionalized health impacts and related damage costs of fine particulate matter (PM 2.5) exposure were computed for the 77 provinces of Thailand by parameterizing PM 2.5 characterization model. The characterization factors for PM 2.5 showed a wide variation for the various provinces ranging between 2 and 130 h of healthy population lifetime loss per kg PM 2.5 emitted. The factors were applied to compare the agricultural waste management of major crops (rice, sugarcane, maize, cassava, and oil palm) in Thailand between the business-as-usual scenario representing current management practices and five alternative scenarios of agricultural waste utilization or open burning. The total health impacts and damage costs of the business-as-usual scenario were 732,065 DALYs and 425 billion Thai Baht (THB), respectively. The open burning alternative scenario yielded additional damage of 524 billion THB. The alternative scenarios of management via animal feed, fertilizer, residues left in the field, and electricity generation provided economic benefits (431, 427, 422, and 399 billion THB, respectively). In this study, using the global average factor to assess the overall health impacts of PM 2.5 emissions in Thailand resulted in an underestimation of health impacts as compared to province-specific factors. While substituting province-specific factors with country average factor yields similar overall results at the country level, using province-specific factors are important to capture the large variability of impacts across individual provinces. In addition to developing a tool to quantify the PM 2.5 related health impacts of various agricultural wastes in Thailand, recommendations on the implementation of the alternative scenarios have also been outlined in the study. [Display omitted] • Health impacts of PM 2.5 emission from agricultural waste management were quantified. • Using regionalized factors yield more accurate results than global/country averages. • Open burning of agricultural residues results in the highest health impacts. • Animal feed and fertilizer production have potential for avoiding health burden. [ABSTRACT FROM AUTHOR]

Oil-Based Drill Cuttings (OBDC) are one of the hazardous wastes of the oil and gas industry. In this study, Reclaimed Asphalt Pavement (RAP), OBDC and Fly Ash (FA) geopolymer were used in Cold Central Plant Recycling (CCPR) mixtures. The dynamic modulus test was used to appraise the viscoelastic properties of CCPR mixtures. The Toxicity Characteristic Leaching Procedure (TCLP) test was also utilized to investigate the long-term contaminants leaching. In addition, a cradle-to-grave Life Cycle Assessment (LCA) and Life Cycle Cost Analysis (LCCA) were conducted to evaluate the potential environmental burdens and economic costs of pavement structures containing CCPR mixtures. Moreover, Multi-Criteria Decision-Making (MCDM) analysis using four different methods was performed to determine the optimal sample. The results revealed that the recycling of OBDC and RAP in stabilized CCPR mixtures with FA geopolymer can improve the viscoelastic properties and prevent the leaching of contaminants from these waste materials. Furthermore, recycling of the mentioned waste materials in CCPR mixtures has caused a significant reduction in global warming, acidification, eutrophication, smog, respiratory effects, Human toxicity, ecotoxicity, and cumulative energy demand up to 41%, 36.6%, 73%, 43%, 47%, 34%, 73%, and 13%, respectively. Additionally, using CCPR mixtures containing the OBCD, RAP, and FA geopolymer in the pavement structure has led to economic benefits of up to 31% compared to the conventional pavement system. [Display omitted] • OBDC and RAP were recycled as alternative aggregates in CCPR mixtures. • Replacing RAP with OBDC enhanced the viscoelastic performance of CCPR mixtures. • Recycling OBDC and RAP in CCPR-stabilized mixtures with geopolymer lowers leaching. • LCA and LCCA reveal benefits from recycling OBDC and RAP compared to landfilling. • MCDM analysis was performed in order to determine the optimal mixture. [ABSTRACT FROM AUTHOR]

Wet free radical advanced oxidation technology such as Fenton reaction is thought to be a very efficient method to remove NO from flue gas, but it requires the consumption of additional oxidants to achieve high removal efficiency. For this purpose, a ligand-enhanced UV-Fenton system without additional oxidants was proposed for NO removal. Three common chelating ligands, EDTA, NTA, and Citrate, were selected to promote UV-Fenton reaction for NO removal. The NO removal performance, mechanism, and kinetics of three different ligand-enhanced photochemical Fenton systems including EDTA/UV/Fe(II), NTA/UV/Fe(II), and Citrate/UV/Fe(II), were studied. Results showed that ligand addition can greatly promote a NO removal in the UV-Fenton system, in the following order of efficiency: EDTA > NTA > Citrate. The mechanism research indicated that these ligands not only enhanced NO oxidation removal by promoting the generation of •OH, but also provided NO complexation removal, which synergized oxidative denitrification and complexation denitrification in the same reaction system, greatly promoting wet NO removal. NO from simulated flue gas was mainly converted into NO 3 −, NO 2 −, NH 4 +, N 2 , and N 2 O through synergistic complexation-oxidation. The optimum ratio of ligand to Fe(II) was 1:1 for EDTA and NTA and 3:1 for citrate. NO removal efficiency was increased and then decreased with the increase in pH value or O 2 concentration. The low temperature was found to be favorable for NO removal. Furthermore, the kinetics demonstrated that the L/UV/Fe(II) system reaction was a pseudo-first-order process involving nitric oxide. Finally, compared with other Fenton and Fenton-like denitrification systems, EDTA(NTA)-enhanced UV-Fenton system had shown great priority in terms of removal performance, absorbent cost, and waste disposal. [ABSTRACT FROM AUTHOR]

Sustainable biowaste utilization is currently an interesting research area to enhance its conversion to value-added products. Electrochemical and bioelectrochemical technologies are cracking up the fractionization of various types of waste for environmental cleanup processes. In the present study, agricultural waste-based extracted material was used to capture the nutrients and/or pollutants from the anaerobic bioelectrochemically treated sewage wastewater (SWW). Hydrogen production potential of 15.52–11.77 times higher than the single carbon source indicated efficient utilization of organic and inorganic matters by extant microorganisms in the SWW. The electrochemical hemicellulose (HC) extraction, nutrient recovery and other components like applied potential (mV), NaOH (M) and rice straw load (%) analysis were evaluated at three factors and three levels. The N/C ratio of 0.06 and the highest functionalities in the 150-mV extracted HC, confirm its suitability to trap nutrients/pollutants from wastewater. With the potential to substitute expensive adsorbents in the future, the additional advantage of HCs being useful in the recovery of ammonium ions for use in agriculture could positively impact the global food security program. The aim of the study is not only the recovery of nutrients from waste but also to unravel the clean path of waste management with possible green energy production. [Display omitted] • SWW showed higher hydrogen and ethanol production potential than SW. • Nutrient recovery from the treated sewage wastewater using HC-based adsorbent. • Applied potential of 150 mV showed more functionality in the biosorbent. • ICP-OES and EDX data confirmed the elements uptake by biosorbent. [ABSTRACT FROM AUTHOR]

The conversion of sludge from sewage treatment plants (STPs) into bioenergy is a promising approach to sustainable energy generation and effective waste management. This process occurs through anaerobic digestion in the biodigesters, resulting in biogas production. However, given that the sludge comes from various STPs in different cities, identifying the ideal locations requires careful selection due to the complexity of sludge management, associated costs, and transportation logistics. In this context, this work aims to formulate a mathematical optimization model to determine the best locations for the installation of sludge processing centers, considering the minimization of the economic, environmental, and social costs. The model is implemented in MATLAB software, and geospatial analysis of the regions of interest is performed using QGIS software. For model validation, three distinct instances are considered. The results obtained demonstrate significant potential in terms of biogas and electricity production, with the highest values for the third instance being 61,997,501 Nm³/year and 149,275 MWh/year, respectively. The proposed methodology represents a crucial step toward sustainability, as it promotes the generation and use of bioenergy from STP sludge and contributes to improved waste management and the prevention of air, soil, and water pollution. • A mixed NLP model is proposed to assist in the process of utilizing sewage sludge. • A genetic algorithm is proposed as a metaheuristic for optimization model solution. • Focus is given to minimizing economic, social, and environmental costs. • Computational experiments with real instances are conducted. [ABSTRACT FROM AUTHOR]

Blockchain technology has the potential to address sustainability challenges in the agri-food industry. This scoping review analyzes 72 papers and finds that blockchain technology can enhance economic, environmental, and social sustainability. By reducing transaction costs, improving transparency, and empowering consumers, it contributes to economic sustainability. Environmental sustainability is enhanced through carbon emissions reduction, waste management, and better environmental impact monitoring. Social sustainability is promoted through food safety, consumer trust, and financial inclusion for small farmers. However, unexplored avenues like obstacle identification, localized solutions, consumer trust factors, crisis resilience, environmental implications, and fair market access require further research. The transformative potential of blockchain in the agri-food industry requires interdisciplinary collaboration to fully harness its benefits for a more sustainable future. [ABSTRACT FROM AUTHOR]

The accurate quantification of construction waste (CW) is prerequisite for achieving zero-waste in the building sector. This study employs a Spatial Material Flow Analysis model considering building life cycle to estimate the spatio-temporal dynamics of CW in Nanjing, China, over two decades. Additionally, it employs an ARIMA model for forecasting CW generation over the forthcoming decade. During 2000 to 2020, Nanjing's CW witnessed a CW increase from 0.8 to 59.0 Tg, predominantly comprising non-metallic materials. Meanwhile, the spatial distribution of CW has widened, accompanied by the emergence of numerous CW hotspots, in parallel with economic and population growth. Future projections suggest a continuous yet decelerating increase in CW generation, highlighting a significant opportunity for resource recovery. The application of this hybrid approach not only enhances CW management accuracy but also supports the broader goal of fostering sustainable building practices. This research expects to enlighten the stakeholders committed to advancing sustainable construction and waste management strategies in the context of zero-waste buildings. [ABSTRACT FROM AUTHOR]

High-temperature molten vitreous (HTMV), as the primary means of hazardous waste disposal, was produced in large quantities. Exploring its potential in photothermal applications could extend its high-value. Herein, the HTMV was used to explore the photothermal performance potential. It indicates that the HTMV possesses significant photothermal conversion capability, capable of increasing the tested water temperature by 6.65 °C. The HTMV mass and water volume are critical factors affecting the water temperature outcomes. The HTMV exhibits distinct conversion capabilities when applied at different application scenarios on the test object. Application on the bottom primarily focuses on photothermal conversion with high heat production efficiency, while side application additionally demonstrates excellent thermal insulation properties. Based on heat balance and backpropagation neural network predictions, optimal scheme of HTMV on both inside and outside bottom application scenarios of the heated object can achieve a maximum heat input of 660.6 kJ m−2 and 570.1 kJ m−2, respectively, and reduce carbon emissions by 0.062 kg CO 2 m−2 and 0.054 kg CO 2 m−2. This study not only provides a foundation for the further application of HTMV but also opens a new direction for the development of photothermal conversion materials, which is of great significance in advancing sustainable energy technology. [Display omitted] • HTMV from hazardous waste shows photothermal potential. • HTMV Attached as bottom can additionally increase water temperature by 6.65 °C. • 660.6 kJ m−2 heating and 0.062 kg CO 2 /m2 reduction can be realized. [ABSTRACT FROM AUTHOR]

With the escalating generation of municipal solid waste (MSW) and the increasing utilization of collection and transportation (C&T) vehicles within the MSW classification system, the associated costs and greenhouse gas (GHG) emissions from waste drop-off, as well as the C&T processes, have risen sharply. However, the mesoscopic view of the waste drop-off and C&T system is limited. Therefore, we divided the waste classification management (WCM) system into three subsystems: generation and drop-off, C&T, and disposal. Based on system dynamics theory, the logical relationships between relevant parameters in each subsystem were established. A WCM system dynamics model, which focused mainly on the drop-off and C&T processes, was constructed using Anylogic software. Using sensitivity, scenario, and uncertainty analyses, the economic impact and GHG emissions of the WCM system were analyzed in detail. The results showed that the waste drop-off and C&T processes accounted for 54.29–57.87% ($47.31 per ton) and 24.54–26.83% ($21.39–21.93 per ton) of the total cost in the whole waste management chain, respectively. GHG emissions were mainly generated in disposal facilities (116.84–257.86 kg CO 2 -eq/t), followed by C&T (19.02–20.55 kg CO 2 -eq/t) and drop-off processes (12.68–18.78 kg CO 2 -eq/t). The system cost and GHG emissions were significantly influenced by the components of the source-separated waste and operational parameters of the applied C&T vehicles. This study not only provides a basis for WCM policy formulation but also a tool for the design and optimization of waste C&T systems. • A system dynamics model was developed for waste classification management. • Collection and transportation sections cost $64.99–72.48/tMSW. • Vehicle operation significantly impacts cost and GHG emissions. • Electric vehicles have limited advantages. [ABSTRACT FROM AUTHOR]

The current surge in plastic waste generation from human activities has led to environmental hazards associated with Sustainable Development Goal (SDG) 6 (Clean Water and Sanitation), from mismanaged polymeric waste and its derived free plastic debris. Chemical recycling enables the effective end-of-life (EoL) of plastic wastes and debris by transforming them into value-added chemicals, reducing their offsite manufacturing's environmental and social risks related to SDG 13 (Climate Action) while mitigating plastic pollution associated with SDG 6, SDG 14 (Life Below Water), and SDG 15 (Life on Land). Herein, this work examines the recent research progress, technological advancements, and policy implications on the chemical recycling of plastic waste and derived debris from macro to micro levels and implications for achieving SDGs. We identify three primary research challenges related to plastic pollution mitigation: 1. Understanding the extent of plastic pollution and consequences by sources originating from human activities; 2. Exploring the sustainable material life cycle of plastics with minimum waste generation, free debris exposure and pollution related to SDGs 14 and 15, and carbon emissions aligned with SDG 13; 3. Indicating the necessary local and global efforts to deploy plastic production, use, and waste management as per sustainable plastic life cycle concepts associated with SDG 12 (Responsible Production and Consumption). Future perspective directions lie in mitigating plastic pollution on both the sources identified by plastic waste and derived debris generation from individual human activity and the sinks associated with free debris exposure to natural environments. Reducing plastic use, waste reuse, repurposing, and recycling can fully mitigate these negative externalities but also generate greenhouse gas emissions, which requires decarbonization under climate commitments. [Display omitted] • Sustainable plastic chemical recycling targets treating both macro and micro wastes. • Recent progress of chemical recycling from macro- to microplastics was reviewed. • Technology improvement and policy implications were listed via literature review. • The plastic pollution level from routines and full mitigation efforts is unknown. • Three perspective research directions were proposed to fill these knowledge gaps. [ABSTRACT FROM AUTHOR]

In today's technologically advancing and increasingly urbanized world, the search for new materials like biochar has become crucial to address environmental challenges such as pollution and agricultural needs. Biochar, derived from pyrolyzed biomass, offers a sustainable solution for soil improvement and pollution control. This review explores biochar's diverse applications in waste management, pollution control, and agriculture, emphasizing its potential for promoting sustainability and circular economy practices, while also discussing emerging applications like supercapacitors. Compared to previous works, this review offers a comprehensive examination of biochar's diverse applications and its potential for future trends in environmental sustainability. [Display omitted] • A review was conducted on the use of biochar for environmental remediation purposes. • Biochar plays a crucial role in enhancing soil health and boosting crop productivity. • Future research in biochar is poised to explore unconventional applications. • Biochar holds significant potential for addressing global. [ABSTRACT FROM AUTHOR]

Efficient management of waste generated in healthcare systems is crucial to minimize its environmental impact and ensure public health. Sustainable medical waste management (MWM) systems require careful network design, which can be achieved through efficient optimization techniques. This work develops a mixed-integer linear programming (MILP) to formulate the problem, a two-step MILP (TSMILP) to generate quality lower bounds, and a novel parallel heuristic algorithm to configure a sustainable waste management system including waste generation centers (WGCs), waste treatment centers (WTCs), waste recycling centers (WRCs), waste disposal centers (WDCs) and waste incineration centers (WICs). Such a hybrid methodology has not been yet offered in the literature wherein the aim is to address strategic (establishment of facilities), tactical (employment of transportation system), and operational decisions (transportation planning) optimally in large networks. As reflected in the literature, there is a huge gap in efficiency and application of combinatorial optimization, and parallel computing in sustainable MWM systems, where the suggested MILPs' solvers are not technically capable of discovering quality solutions in reasonable runtimes on large-sized instances. Thus, we suggest a novel heuristic equipped with parallel computing to share the complexity of the problem, with all the CPU cores to shorten runtime. Comparing the results generated by the parallel heuristic with those of the sequential heuristic, the MILP, and the TSMILP on three sets of benchmark instances using Nemenyi's post-hoc procedure for Friedman's test, it is inferred that the parallel heuristic is so effective in coping with the problem, and produces high-quality solutions, especially on the large-sized set. Finally, sensitivity analysis is adopted to analyze the effects of parameters on the objective values and provide useful managerial insights. [ABSTRACT FROM AUTHOR]

Biosolids, derived from wastewater treatment processes, have garnered increasing attention as a valuable resource due to their rich organic and inorganic constituents, which can be beneficially utilized in multiple sectors, including agriculture, civil engineering, and energy recovery. The present review article begins by providing an overview of biosolids, including their production methods and classification based on treatment processes. Subsequently, the chemical composition of biosolids is explored, highlighting the diverse array of organic and inorganic components present. The characterization techniques employed for analyzing biosolids, such as spectroscopy, chromatography, and microscopy, are thoroughly discussed, emphasizing their role in determining the quality and suitability of biosolids for different applications. Furthermore, the environmental impacts associated with biosolids disposal are extensively examined. This includes the potential risks posed by heavy metals, pathogens, and emerging contaminants, as well as strategies for mitigating these risks through proper treatment and management practices. In addition to environmental considerations, the article explores the various products that can be derived from biosolids. These include organic matter-rich soil amendments for agricultural applications, inorganic nutrient supplements for enhancing plant growth, and the potential for energy recovery through anaerobic digestion and thermal conversion technologies. The utilization of biosolids in civil engineering projects, such as landfill capping and construction materials, is promising. Land application of biosolids also can have economic and waste management benefits (e.g., conservation of landfill space; reduced demand on non-renewable resources like phosphorus; and a reduced demand for synthetic fertilizers). [Display omitted] • The utilization of biosolids and their environmental impacts and disposal was reviewed. • The nutrient content of biosolids provides insight into their agronomic utility. • Methane and biogas production is an emerging technique for recovering energy from biosolids. • The conversion of biosolids into useful materials is significant. [ABSTRACT FROM AUTHOR]

Typical organic waste in urban and rural regions (TWUR) is big in volume and poor in resource utilization, and there is currently a lack of integrated evaluation studies on the optimal pattern of TWUR resource utilization. Based on a representative case study of China's circum-Taihu Lake region, this study integrated material flow, life cycle assessment and comprehensive evaluation methods to explore the optimal scenario pattern for TWUR disposal and utilization under multi-scenario settings from multiple perspectives, including cost-benefit-technology-resource depletion. The synergistic coupled aerobic fermentation scenario in Scenario S2, which has a high level of technological maturity and can maximize nutrient recycling while minimizing environmental impacts, is the optimal scenario for using TWUR, according to the results of the entropy weight-TOPSIS integrated evaluation. Following the implementation of Scenario S2, 20% of the chemical fertilizers utilized in the study region will be substituted with organic fertilizers, resulting in a $16.19 billion reduction in organic waste disposal expenses and $228.64 billion in economic benefits. Additionally, China's carbon emissions will drop by 94.316 million tons as a result. This study validates that the optimal configuration pathway to achieve TWUR resource usage is synergistic coupled aerobic fermentation, in contrast to the majority of prior studies. In addition to being a valuable reference for TWUR's resource use transition and future market planning, this environmental technology analysis will help China in achieving its carbon emission reduction targets. [Display omitted] • Multi-source typical organic waste disposal and utilization models were constructed. • Scenario 2 is the optimal pattern according to the multivariate integrated evaluation. • TWUR disposal pattern shift improves N/P recovery and reduces environmental impacts. • Promotion of optimal scenario will reduce disposal costs and yield vastly benefits. • TWUR rational disposal could offset 0.82% of the nation's CO 2 emissions. [ABSTRACT FROM AUTHOR]

Chain elongation (CE) is a promising technology that can produce medium-chain fatty acids (MCFAs) from sewage sludge, reaching the dual benefits of waste management and clean energy production. The feasibility of using biochar to enhance CE efficiency was examined in this study, where the underlying promoting mechanisms and optimal biochar dosage were also simultaneously explored. Biochar improved the carbon conversion and electron transfer efficiency of CE. The highest caproate concentration (3347.95 mg/L) occurred in the group with 10 g/L biochar addition, and caprylate was most accumulated (612.36 mg/L) when biochar dosage was 20 g/L. The electroactive genera positively related to MCFAs (e.g., norank_f__JG3 0-KF -CM45 and Acetobacterium) were noticeably enriched by low dosage, but the acidification genera proliferated better under excessive dosage. The different MCFAs production induced by varied biochar dosages was closely related to the genera Dysgonomonadaceae. The strengthened dominant CE pathways, FAB, might account for the promoted MCFAs production. [Display omitted] • Biochar accelerated substrate utilization and MCFAs production from sewage sludge. • Low biochar dosage enriched CE bacteria and enhanced their syntrophic metabolism. • Acidification bacteria proliferated better than CE bacteria under excessive biochar. • Dysgonomonadaceae was tightly related to varied MCFAs caused by biochar dosage. • Biochar reinforced the dominant status of the FAB metabolic pathway. [ABSTRACT FROM AUTHOR]

Smouldering is a novel low-energy, low-cost and high-effective technology for the disposal of high-moisture wastes. Most of the existing reports focus on the lab-scale studies and non-continuous operation, but the study about the large-scale device and continuous process is lacking. This work scales up the self-sustained smouldering from the lab-scaled device to the pilot-scale device for treating the printing and dyeing sludge (PDS) with high moisture (over 60%) under continuous operation. Firstly, the lab-scale smouldering experiments with different sand/PDS mixing ratios are performed, and the 4.5/1 mixing ratio is selected as a suitable mixing ratio. Then, the pilot-scale smouldering experiments are carried out and the influence of the discharging residual interval (50s, 35s, 20s) on the reaction stability is tested under continuous operation. Results indicate that the 35s for discharging residual interval may be suitable to maintain the high-temperature region at a relatively stable location under the studied operating condition. The flue gas concentrations are relatively stable during discharging residual, and the main component concentrations are 17.0–17.8% for O 2 , 2600∼3000 ppm for CO, 20∼35 ppm for VOCs, and 60∼80 ppm for NO x , 0.0415–0.0836ngTEQ/m3 for dioxin, respectively. The research in this study can give helpful information for the application of the continuous smouldering treatment in the future. [Display omitted] • Smouldering is scaled up from lab-scaled to pilot-scale for treating PDS. • Continuous operation is successfully performed in pilot-scale device. • Effect of discharging residual interval on smouldering is tested and 35s is suitable. [ABSTRACT FROM AUTHOR]

Plastic waste pollution is a challenging and complex issue caused mainly by high consumption of single-use plastics and the linear economy of "extract-make-use-throw". Improvements in recycling efficiency, behaviour changes, circular business models, and a more precise waste management system are essential to reduce the volume of plastic waste. This paper proposes a simplified conceptual model for a smart plastic waste separation system based on sensor technology and deep learning (DL) to facilitate recovery and recycling. The proposed system could be applied either at the source (in a smart waste bins) or in a centralised sorting facility. Two smart separation systems have been investigated: i) the one utilising 6 sensors (near-infrared (NIR), humidity, temperature, CO 2 , CH 4 , and a laser profile sensor) and ii) the one with an RGB camera to separate packaging materials based on their composition, size, cleanliness, and appearance. Simulations with a case study showed that for a camera-based sorting, Inception-v3, a DL model based on convolution neural networks (CNN), achieved the best overall accuracy (78%) compared to ResNet-50, MobileNet-v2, and DenseNet-201. In addition, the separation resulted in a higher number of misclassified items in bins, as it focused solely on appearance rather than material composition. Sensor-based sorting faced limitations, particularly with dark colouration and organic matter entrapment. Combining the information from sensors and cameras could potentially mitigate the limitations of each individual method, thus resulting in higher purity of the separated fractions. [Display omitted] • Plastic packaging waste is separated using sensors and deep learning algorithms. • The Separation is based on plastic type and cleanliness. • Inseption-V3 yielded the best classification results (78.34 %). • Sensors resulted in a better identification of dirty packaging items then camera. • Both methods minimised the number of items in the mixed waste bin. [ABSTRACT FROM AUTHOR]

China's construction and demolition waste has been substantially increasing due to the country's urbanization. However, since the recycling rate of construction and demolition waste is still much lower in China compared to most developed countries, its construction industry still relies heavily on natural resource consumption and is very much a linear economy. Although a circular economy for construction and demolition waste management has been promoted by the government in recent years, the transition from open-ended to close-looped circularity for construction and demolition waste management strategies have not been fully investigated. This study therefore identifies stakeholder engagement and closed-loop key strategies as part of a circular economy for construction and demolition waste management in China. Integrated approaches are used to achieve the aim of this study including literature review, semi-structured interview, questionnaire survey, and causal loop diagram development. The stakeholder engagement and key strategies were identified through literature review, semi-structured interviews, questionnaire survey, and statistical analysis. A causal loop diagram was then developed to demonstrate the interconnection and causal effect between stakeholders and key strategies. The findings reveal that stakeholder engagement and key strategies are highly interrelated for achieving closed-loop construction and demolition waste management. Government ranks as the most important stakeholder engagement, and improving secondary material quality and value is the most important key strategies. This study provides insights for practitioners and academics alike to help understand the interrelationship between stakeholder engagement and key strategies as part of a circular economy for construction and demolition waste management in China. [ABSTRACT FROM AUTHOR]

Efficient waste management practices play a critical role in addressing the acute challenges of environmental protection, public health and resource conservation. A well-designed system guarantees that waste is efficiently collected, treated and disposed while minimizing negative impacts on ecosystems and human well-being. This work presents a robust bi-level decision support system to establish a sustainable waste management system using a co-modal transportation network to treat municipal solid waste timely and efficiently. Consequently, two integrated multi-objective mathematical models are developed to formulate the problem. Configuring the municipal solid waste network in the first level of the suggested decision support system, the transportation network is designed in the second level taking into account non-identical modes. The objectives are to minimize total cost and total emission in both levels, while maximization of total job creation is also addressed in the first level. Robust optimization method and weighted goal programming method are then utilized to accommodate the developed decision support system against uncertainty and multi-objectiveness, respectively. To validate the efficiency of these methods, they are assessed against possibilistic linear programming technique and Lp-metric approach with the help of simple additive weighting (SAW) method, respectively. Eventually, several numerical examples are generated based on the benchmarks given in the literature, which are then tackled using CPLEX solve to appraise the applicability and complexity of the developed methodology. The findings reveal the efficacy of the decision support system in terms of finding solutions in less than 448 s on average. Finally, sensitivity analyses are performed to draw out useful practical implications and decision aids. • Designing a bi-level decision support system for municipal solid waste management • Addressing sustainable development by developing two novel multi-objective models • Applying robust optimization technique to deal with uncertainty • Implementing weighted goal programming to treat multi-objectiveness • Conducting a set of sensitivity analyses to draw managerial insights [ABSTRACT FROM AUTHOR]

To meet increasingly stringent standards of Nitrogen oxide (NO x), it is highly desirable to develop high-efficiency denitration technology during hazardous waste incineration. Therefore, a state-of-art decoupling combustion technology of liquid hazardous wastes (LHW) has been proposed to achieve low NO x emission. In this technology, LHW is introduced into a low-NO x reactor to reduce NO x generated from solid hazardous waste (SHW) incineration prior to its complete combustion. The present article is devoted to clarifying the optimal conditions for denitration reactions by LHW, so the capabilities of nitric oxide (NO) reduction by reduction by LHW model compounds, namely methanol and methylbenzene, were evaluated in fixed-bed and fluidized-bed reactors. The highest denitration efficiency is 78.9% at 900 °C for methanol and 70.0% at 1000 °C for methylbenzene in the test temperature range. The NO reduction activities were closely associated with cracking characteristics of LHW. The presence of oxygen (O 2) exhibited different effects on denitration: it promoted NO reduction at low temperatures due to the generation of more denitration-favored agents but suppressed NO reduction at high temperatures due to the oxidation of denitration-favored agents into CO 2 and H 2 O by excessive O 2. Moreover, the fluidized-bed reactor, characterized by good heat transfer, exhibited an approximately 17% higher NO reducing efficiency compared to the fixed-bed reactor at low temperatures, but both reactors demonstrated similar NO reduction efficiencies of around 83% at high temperatures. In addition, methanol and methylbenzene showed higher NO reduction efficiencies than their cracking-produced reducing gases, with the reducing gases accounting for approximately 50% of the overall NO reduction efficiency at 1000 °C. According to the above results, a two-step denitration reaction pathway was proposed in which both cracking-formed free radicals and reducing gases contribute to the overall NO reduction. The results of this study can provide valuable insights for NO reduction in the hazardous waste disposal. [Display omitted] • Unavailability of SCR in hazardous waste incineration. • Decoupling combustion of liquid hazardous waste. • Effects of temperature and O 2 on denitration. • A two-step denitration reaction pathway. • Potential practical NO reduction application. [ABSTRACT FROM AUTHOR]

Unsustainable waste management practices impose severe environmental hazards, health risks, and financial burdens. Waste valorization systems have emerged to mitigate the negative impacts of landfilling while recovering finite materials and renewable energy. This study aims to develop a life cycle assessment (LCA)-based multi-criteria framework using linear programming to optimize municipal waste allocation to multiple valorization facilities. The developed optimization model minimizes the life cycle impacts of integrated waste management on several life cycle impact categories. A multi-criteria decision-making analysis is implemented to account for the relative importance of the examined environmental categories, and a sensitivity analysis is conducted to study the effect of varying the importance weights. The variation between different LCA methods, IMPACT, CML, and ReCiPe, is also investigated. The proposed framework is applied to Egypt based on local conditions and strategic priorities. The LCA findings reveal that processing recyclables in material recovery facilities enhances the environmental performance in all impact categories except ozone layer depletion. To achieve minimum environmental effects on the assessed impact categories, single objective models suggest the diversion of recyclables to material recovery facilities and non-recyclables to gasifiers. The Pareto front of IMPACT involves anaerobic digesters and incinerators, CML comprises composting facilities, and ReCiPe includes incinerators. Overall, this study provides a lifecycle-based decision-making guide for the planning and optimization of sustainable waste management systems, and highlights the potential variations in the outcomes of different LCA methods adopted. • Single/multi-objective optimization was conducted based on three standard LCA methods. • Recovering recyclables led to + ve lifecycle impacts in most environmental categories. • Composting organics imposed negative impacts in all categories except global warming. • Single-objective optimization suggested recovering recyclables and incinerating others. • Findings showed a significant variation among different lifecycle assessment methods. [ABSTRACT FROM AUTHOR]

In Malaysia, the challenge of managing the burgeoning volume of food waste in an environmentally sustainable manner is critical, given the country's rapid urbanization and the resulting increase in waste. This review article critically examines contemporary efforts and technologies in food waste management, focusing on anaerobic digestion (AD), incineration, and the emerging Hydrothermal Carbonization (HTC) technology, emphasizing their application within the Malaysian context. It is observed that landfills, currently the predominant method for waste disposal, contribute significantly to environmental degradation, highlighting an urgent need for sustainable alternatives. AD is identified as a beneficial approach, offering the dual advantages of waste volume reduction and biogas production; however, it is hindered by technical and economic challenges. Incineration, while effective in waste reduction and energy recovery, raises concerns regarding potential emissions of carcinogenic substances and its economic feasibility. The novel HTC technology, on the other hand, presents a promising avenue for converting food waste into Hydrochar, a carbon-rich product, demonstrating the potential for environmental sustainability and economic viability. The review underscores the imperative of optimizing these technologies to suit Malaysia's specific conditions, suggesting that future research should focus on enhancing HTC's application. This comprehensive evaluation aims to contribute to advancing sustainable food waste management practices, advocating for integrated solutions that are environmentally responsible, economically feasible, and socially acceptable. [Display omitted] • Malaysia's food waste at 16688 t/day; 80% landfill reliance. • Anaerobic digestion: potential vs. high investment. • Incineration reduces waste but raises cost, emissions. • Hydrothermal Carbonization (HTC) emerges as future solution. • Need for tailored solutions in Malaysia's unique context. [ABSTRACT FROM AUTHOR]

The generation of waste materials is an inevitable byproduct of various human and ecological activities. Inadequate management of waste materials can have detrimental effects on the environment, leading to long-lasting harm to both living organisms and the broader ecosystem. A waste-to-sustainable energy concept based on TENGs is a new research technology added to the other green and renewable energy technologies. It is highly efficient technology in using a wide range of waste materials to convert chaotic environmental energies into green electricity for various intelligent applications. In this review, waste materials are classified into non-degradable waste (plastic waste), bio-degradable waste, and a combined waste. These types of waste materials showed great capability in converting low frequency wasted mechanical energies into electrical pulses for various applications, including healthcare, IoT and wireless technologies, and smart buildings. It is worth noting that utilizing plastic waste as tribo-pairs doe does not compromise the performance efficiency of the fabricated TENGs. For instance, a non-modified X-ray waste filmwas used as a positive tribo-layer for force sensing application. The TENG showed great performance with maximum power density of 1.39 W/m2 which is comparable to the TENGs fabricated using prepared tribo-materials. We propose waste-to-sustainable energy technology based on TENGs as a promising and sustainable alternative for the generation of renewable energy and the upcycling of waste materials. [Display omitted] [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic has had a significant impact in various areas, particularly in health, and the search for new therapeutic and preventive approaches remains crucial. In this study, we investigated the antiviral potential of bio-oil (BO) obtained from residual woody biomass of Citrus sinensis. BOs were produced through pyrolysis at different heating rates (1, 3, 5, and 7 °C min−1) and subsequently underwent a purification process. Physical-chemical analyses and identification of chemical compounds were performed using Gas Chromatography-Mass Spectrometry (GC/MS). Furthermore, the hemolytic capacity of BOs and their activity against the 3 C L protease enzyme (3CLpro) of SARS-CoV-2 were evaluated. The heating rate was found to affect the chemical properties of the BOs, resulting in variations in pH and chemical composition. A total of 23 chemical compounds were identified, with a significant presence of furans, pyrans, and phenolic compounds. Regarding hemolytic capacity, concentrations equal to or below 1% of BOs showed no hemolytic effect. Concerning antiviral activity, the BO obtained at a heating rate of 5 °C min−1 demonstrated greater efficacy in inhibiting SARS-CoV-2 compared to the BO obtained at a heating rate of 1 °C min−1. This antiviral activity may be associated with the synergistic action of the chemical compounds present in the bio-oils, especially phenolic compounds. These results indicate that the chemical and antiviral properties of BOs can be influenced by the heating rate used during production. In addition, these are unprecedented results and will serve to guide future research aimed at the use of the pyroligneous liquid for the development of a bioactive product. [Display omitted] • The heating rate applied during pyrolysis affects the pH of the bio-oil. • Bio-oil obtained with higher heating rates are rich in phenolic compounds. • A concentration of 1% of bio-oil exhibits non-hemolytic activity. • The concentration of phenolic compounds in bio-oil affects the anti-SARS-CoV-2 3CLpro activity. [ABSTRACT FROM AUTHOR]

Polyhydroxyalkanoate (PHA) is a biodegradable biopolymer synthesized from renewable resources, providing sustainable and eco-friendly plastics. The utilization of activated sludge for PHA production has gained prominence due to its cost-effectiveness and abundant availability. Upscaling PHA production from activated sludge can contribute to waste management and resource recovery simultaneously, thereby reducing the dependence on petroleum-based plastics. This review critically examines the progress and challenges in this field, while offering valuable insights into strategies for enhancing productivity, improving product quality, and reducing costs. The analysis primarily focuses on identifying key factors influencing each stage of the three-stage process aimed at increasing productivity. Noteworthy strategies proposed include optimizing the enrichment process and feast/famine ratio. For high-quality PHA, the emphasis is on oriented acid production, and the selection of appropriate extraction methods is crucial. The review also addresses cost reduction, discussing the simplification of the process through the two-stage process, and integration of nitrogen removal with PHA production. Future research directions are outlined, highlighting the optimization of PHA quality, scalability of production, development of efficient extraction methods, assessment of environmental impacts, and alignment with policy measures. Conclusively, activated sludge-based PHA production shows great promise and necessitates further research and development for industrialization. [Display omitted] • Activated sludge proves ideal resource for PHA production. • Industrialization challenges are low productivity, quality issues and high costs. • Solutions for industrial PHA production from activated sludge are discussed. • Advancements are required for the transition to successful commercialization. [ABSTRACT FROM AUTHOR]

The copper dust derived from the double-flash copper smelting process contains high level of arsenic with almost zero positive potential impurities. This study explores a new process for the preparation of high-purity copper through selective leaching of arsenic-rich copper dust with waste acid-purification-electrodeposition. Furthermore, the study also explores the causes and solutions for recurrent occurrence of excessive Hg impurity content. The results indicate that, the high-purity copper that meets standard 6 N (China) requirements and exhibits smooth surface, dense crystallization, and uniform color can be obtained under the optimal conditions of 200 A/m2 current density, electrolyte sulfuric acid concentration of 120 g/L, additive dosage of 120 g/t·Cu, electrolysis temperature of 50 °C, electrode spacing of 45 mm, endpoint Cu2+ concentration of 30.50 g/L, with C1 used as active adsorbent to purify the electrolyte. The current efficiency can be up to 99.65 %, with average tank voltage of 1.87 V and electrical energy consumption of 1582.93 kW h/t⋅Cu. There will be good environmental and economic benefits with this process of co-disposal and high-value recovery of arsenic-rich copper dust and waste acid. • Co-disposal of waste acid and arsenic-rich copper dust economically. • The reasons and solutions for Hg impurity in high-purity copper were investigated. • 6 N high-purity copper is obtained by one-step electrodeposition. [ABSTRACT FROM AUTHOR]

Volatile organic compounds (VOCs) and pathogens that are generated during fermentation of food waste by microorganisms have caused odor annoyance and health risks. In this work, the evolution profiles of them during aerobic decomposition of inter-type and intra-type food waste were compared in laboratory-controlled reactors for three months. The emission fluxes of VOCs reached peak on the 10th day (except fish waste), then decreased sharply until leveled off. For vegetable waste, watercress emitted higher concentrations (2.5 × 104−2.4 × 106 μg/m3) and emission fluxes of VOCs (5.4−508 μg kg−1·h−1) than pepper and onion. While for meat waste, the emitted VOCs from fish (1.4 × 105−8.4 × 106 μg/m3 and 68.4–4.3 × 103 μg kg−1·h−1) were higher than chicken and pork. Dimethyl trisulfide (DMTS) and ethyl acetate as well as DMTS and methyl methacrylate were dominant oxygenated VOCs and volatile organic sulfur compounds in vegetable and meat wastes, respectively. The odor from the leachate was attributed to the emitted sulfur-containing compounds. The main fermented bacteria in intra-type food waste were highly similar, but differed greatly between the inter-type food waste with Lactobacillus and Comamonas as well as Peptoniphilus and Wohlfahrtiimonas as the major fermented bacteria in vegetable and meat wastes, respectively. Significant correlations between microbial community and VOCs including ethyl acetate, DMDS and 2-butanone were observed. As predicted by functional annotation of prokaryotic taxa (FAPROTAX), Lactobacillus and Bacteroides were correlated with the respiration of sulfur-containing compounds and hydrocarbon degradation, respectively, suggesting that production of VOCs was contributed mainly by bacteria communities. Pathogenicity of food waste was mainly due to Enterococcus , Proteobacteria , Mycobacterium and Salmonella. Our results are conductive to develop countermeasures to reduce VOC emission during food waste decomposition. [Display omitted] • VOSCs and OVOCs were the dominant VOCs emitted from food waste fermentation. • The released unpleasant odor was attributed to the sulfur-containing compounds. • Intra-type and inter-type food waste had similar and different bacterial communities. • Ethyl acetate, 2-butanone, VOSCs were correlated with microbial communities. • Enterococcus, Proteobacteria, Mycobacterium , and Salmonella were the main pathogens. [ABSTRACT FROM AUTHOR]