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Food waste (FW) being a major solid waste component and of degradable nature is the most challenging to manage and mitigate greenhouse gas emissions (GHEs). Policymakers seek innovative approaches to achieve net zero objectives and recover resources from the FW which requires a comparative and holistic investigation of contemporary treatment methods. This study assessed the lifecycle of six alternative scenarios for reducing net GHEs and energy use potential from FW management in a metropolis, taking Hong Kong as a reference. In both impact categories, the business-as-usual (landfilling) was the worst-case scenario. The combined anaerobic digestion and composting (ADC) technique was ranked best in the global warming impact but was more energy intensive than anaerobic digestion with sludge landfilling (ADL). Incineration ranked second in net GHEs but less favourable for energy recovery from FW alone. The proposed integration of FW and biological wastewater treatment represented an enticing alternative. Integration by co-disposal and treatment with wastewater (CoDT-WW) performed above average in both categories, while anaerobic co-digestion with sewage sludge (AnCoD-SS) ranked fourth. The sensitivity analysis further identified critical parameters inherent to individual scenarios along with biogenic carbon emission and sequestration, revealing their significance on the magnitude of GHEs and scenarios' ranking. Capacity assessment of the studied treatment facilities showed a FW diversion potential of ∼60% while reducing the net GHEs by ∼70% compared to the base-case, indicating potential of net zero carbon emissions and energy footprint by increasing treatment capacity. From this study, policymakers can gain insights and guidelines for low-carbon urban infrastructure development worldwide., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Ltd.)

This study presents a novel life cycle assessment-based framework for low-impact offshore oil spill response waste (OSRW) management. The framework consists of design of experiment, life cycle assessment (LCA), multi-criteria decision analysis (MCDA), operational cost analysis, and generation of regression models for impact prediction. The framework is applied to four OSRW management strategies as different combinations of solid and liquid oily waste collection, segregation, transportation, and treatment/disposal technologies. Hypothetical scenarios based on oily waste compositions are developed, and the associated environmental impacts and operational costs are evaluated. The LCA results show that oily waste composition accounts for < 5% of the total environmental impacts. Chemical demulsification has the highest total impacts due to high marine ecotoxicity and human toxicity, followed by incineration and transportation. The cost analysis reveals that the strategy comprised of centrifugation and landfilling is most preferable while the combination of chemical demulsification and incineration is least favorable. The strategy of combined use of centrifugation and landfilling is ranked as the most suitable in the MCDA. Regression models are developed to predict environmental impacts based on important factors. The framework can help waste management practitioners select low-impact strategies for handling offshore OSRW., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Considering the volume of plastic generation and its persistence in nature, the management of plastic wastes has gained increasing attention globally. To select the most environmentally sustainable solution, insights in the environmental impacts of different management strategies are crucial. This study thus aimed to evaluate different plastic waste management strategies such as mechanical recycling, incineration, industrial incineration, construction and landfill, and exemplified with potential case demonstrations in Hong Kong. The environmental impacts of the developed strategies are comparatively evaluated by the lifecycle assessment (LCA) technique in order to identify the most environmentally preferable strategy. The LCA results indicate that industrial incineration is the most potential preferential strategy for Hong Kong, as it can potentially consume the generated waste locally and substitute the imported coal for the cement industry. Mechanical recycling is the second preferential strategy for the city, as it conserves secondary resources significantly. Grate incineration for generating electricity is the third preferable solution, while the use of recycled plastics in construction may not be a benign environmental strategy for Hong Kong. The findings of this study could help policy makers to design strategic direction for environmentally sustainable management of plastic wastes locally based on the circular economy principle., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Resource recovery is a promising solution for multiple waste and economic challenges worldwide. Although the life cycle environmental performance of resource recovery systems has been widely studied, the impacts of their resultant waste processing byproducts remain unassessed. Depending on their management techniques and destinations, such large waste streams, such as non-recovered recyclables and anaerobic digestate, may significantly alter the overall environmental footprint of the integrated solid waste management (ISWM) strategy. This research aimed to assess the life cycle impacts of various ISWM strategies incorporating material recovery and waste-to-energy (WTE) systems. The examined strategies were based on combinations of incineration (INC) and anaerobic digestion (AD) plants, in addition to material recovery facilities (MRFs) and landfills. The study used eighteen scenarios to explore the effect of the potential pathways of waste processing byproducts on the overall carbon footprint of the strategies. The proposed lifecycle assessment framework was applied to an emerging metropolis. The highest energy recovery was achieved in the dual AD and INC scenarios, particularly when the digestate was incinerated, followed by the mono INC scenario. The highest material recovery, specifically recycled materials and digestate, was accomplished in the MRF+AD and MRF +AD+INC scenarios, in which digestate was marketed and non-recovered recyclables were incinerated. It was found that alternative pathways of waste-processing byproducts can reduce the overall global warming potential (GWP) of the base scenarios. Combining MRF and INC as well as MRF, AD, and INC while incinerating non-recovered recyclables, disposing ash, and marketing digestate (if any) were the optimum environmental options in terms of GWP. Incineration of non-recovered recyclables reduced carbon emissions by 29% compared to disposal, whereas marketing and incinerating the digestate positively impacted GWP compared to landfilling (83 and 77%, respectively). A breakdown of the sub-processes revealed that the energy recovery, recycling, and landfilling processes had the highest contributions to the total GWP (up to 88, 92, and 98%, respectively); the collection and transportation processes had the least impacts (2 and 13%, respectively). The more waste-processing byproducts were incinerated, the greater GWP contribution of energy recovery., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

The environmental impacts from three management alternatives for organic fraction of municipal solid waste were compared using lifecycle assessment methodology. The alternatives (sanitary landfill, selective collection of organic waste for anaerobic digestion and anaerobic digestion after post-separation of organic waste) were modelled applying an attributional as well as consequential approach, in parallel with the aim of identifying if and how these approaches can affect results and conclusions. The marginal processes identified in the consequential modelling were in general associated with higher environmental impacts than average processes modelled with an attributional approach. As all investigated waste management alternatives result in net-substitution of energy and in some cases also materials, the consequential modelling resulted in lower absolute environmental impacts in five of the seven environmental impact categories assessed in the study. In three of these, the chosen modelling approach can alter the hierarchy between compared waste management alternatives. This indicates a risk of underestimating potential benefits from efficient energy recovery from waste when applying attributional modelling in contexts in which electricity provision historically has been dominated by technologies presenting rather low environmental impacts, but where projections point at increasing impacts from electricity provision in coming years. Thus, in the present case study, the chosen approach affects both absolute and relative results from the comparison. However, results were largely related to the processes identified as affected by investigated changes, and not merely the chosen modelling approach. The processes actually affected by future choices between different waste management alternatives are intrinsically uncertain. The study demonstrates the benefits of applying different assumptions regarding the processes affected by investigated choices - both for provision of energy and materials substituted by waste management processes in consequential LCA modelling, in order to present outcomes that are relevant as decision support within the waste management sector., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

In recent years, increased light has been shed on the large amounts of food wasted along the food supply chain (FSC). As lifecycle assessments (LCAs) are commonly used for estimations of environmental impacts from food production, it is relevant to investigate and discuss how such wastage is reflected in foodstuff LCAs. The objective of the present paper is to review a larger set of LCAs of foodstuff in order to (1) investigate if and how wastage along the FSC is addressed and (2) explore the importance of including wastage accumulated along the FSC in terms of environmental impacts. Twenty-eight LCA case studies and two review papers, focusing on tomatoes, were reviewed and greenhouse gas (GHG) emissions chosen as indicator for the second objective. Only one third of the studies consider wastage at some part of the supply chain, in many cases in an inconsistent manner, and only in nine cases were GHG emissions from wastage included in overall systems GHG emissions. In these, wastage accounts for between 2 and 33% of total contribution to climate change. Omitting wastage when conducting LCA of foodstuff could result in underestimations of environmental impacts. Occurrence of wastage along all phases of the supply chain should be acknowledged in order to estimate environmental benefits from prevention and to identify areas where strategies with the aim of reducing wastage could be most efficient.

Urban animal farming is becoming increasingly important in feeding the growing population of many sub-Saharan African cities. However, management of the animal manure generated is proving to be challenging due to space restrictions. Vermicomposting is one of the methods proposed to address this challenge. This study investigated the environmental performance of the vermicompost system by measuring the gaseous emissions generated from the system. In addition, the vermicompost system was compared with other manure management systems currently in use, using life cycle assessment (LCA) methodology. The emissions factors for the vermicompost system were found to be 10.8, 62.3 and 12.8 g/Megagram biowaste for methane, nitrous oxide and ammonia, respectively. LCA showed satisfactory performance of vermicomposting in terms of global warming and eutrophication potential, although if the vermicompost generated is dumped, this could lead to increased eutrophication. However, this is still much lower than the eutrophication caused by open dumping of untreated manure., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Food waste (FW) increases with urbanization and population growth, which puts pressure on the treatment system, causing a variety of harmful impacts on the environment. Proper FW treatment is imperative for ecological integrity and public health. Even though FW treatment is an extensively studied topic, the sustainable FW treatment considering holistic-lifecycle-based environmental impacts has rarely been evaluated. This study addresses this gap through a comprehensive analysis of various FW treatment methods, including co-treatment with sewage, anaerobic digestion, incineration, and aerobic composting. The impacts of greenhouse gas (GHG) emission and energy use efficiency are assessed by analyzing diverse FW treatment methods in Shenzhen, China. The study indicates that FW addition to sewage does not adversely affect the current sewage treatment plant, but benefits GHG avoidance and energy recovery. Compared with the other FW treatment methods, FW anaerobic digestion avoids the most GHG emissions with −71.3 kg CO2 eq/FU and recovers the most energy with −223 kWh/FU, followed by FW co-treated with sewage. The energy conversion efficiency of the combined heat and power (CHP) unit greatly affects FW incineration, while energy consumption in incineration and anaerobic digestion (AD) process is relatively minor. Perturbation analysis pinpoints key parameters influencing outcomes, including CHP efficiency, GHG emission factor of local electricity, and chemical oxygen demand (COD) in FW with ratios of −13~−0.942, −0.518~0.22, and −13~1.01, respectively, that should be given special attention. This study sheds light on sustainable FW management strategies, not only in China but also transferrable to regions confronting similar challenges. Advocating ecologically balanced and resource-efficient approaches, the study aligns with broader aims of fostering sustainable development. [ABSTRACT FROM AUTHOR]

Excess waste tires in Puerto Rico pose health and fire hazards. A policy was proposed to switch 75% of paving materials to asphalt modified with recycled ground tire rubber (GTR). Recycling would mitigate the health risks and fire hazards while reducing the dependence on the export of waste tires for energy recovery. This study uses a lifecycle assessment (LCA) and two scopes to inform the policy from an environmental perspective. The pavement-level analysis compares the conventional and rubberized pavement pilot sections. The system-level analysis evaluates the consequences of the policy's tire diversion from tire-derived fuel (TDF) to GTR. In doing so, this study bridges the gap between the waste management LCAs (focused on processing and less on the use of recycled products) and pavement LCAs (which assess GTR in pavements but not potential waste stream reductions). The results of the pavement-level analysis indicated that GTR pavements present higher impacts than their conventional counterparts. The increased impacts of the GTR section are primarily due to the higher binder content, increased mixing energy, and the binder modification process. The system-level analysis revealed that paving in Puerto Rico can use 6–16% of annual waste tires. When TDF replaces environmentally intense kiln fuels (coal and petroleum coke), tire diversion into GTR is not environmentally beneficial. Conversely, when replaced fuels are more environmentally friendly (coal and natural gas), tire diversion to GTR may present benefits. With the use of greener fuels in the cement industry, GTR deployment may gain interest. [ABSTRACT FROM AUTHOR]

Considering rapid economic development and continuously increasing environmental concerns, end-of-life vehicles (ELVs) have significant socioeconomic value as a crucial waste stream. The research relating to ELVs has rapidly evolved over the last few years. However, existing review studies focus on specific research themes, and thus, fail to present a complete picture. Hence, this research intends to explain the current research scenario relating to ELVs by reviewing the critical published studies of the last 22 years. A total of 1405 research publications were extracted from the Scopus database covering the period from 2000 to 2021. Mainly employing bibliometric analysis techniques, this research analyzes the quantity of literature, researchers, institutions, countries, and research themes to understand the current status and future trends in ELV recycling and management. The results revealed a considerable rise in the number of articles published in the last five years. The key producers of influential ELV research are listed as the United States, China, and the United Kingdom. Globally, Chinese universities have the most ELV-related articles published. Similarly, Serbian researcher Vladimir Simic authored the most ELV-related articles during the research period. This article also identifies various research themes: management and recycling, resource recovery and components, life cycle evaluation, and socioeconomic effects. The results also reveal a strong association between distinct ELV research clusters. [ABSTRACT FROM AUTHOR]

Polyethylene terephthalate (PET) is the preferred packaging material for beverages in the petrochemical industry. In this study, PET waste bottles were used to prepare cost-effective sustainable green fiber through green electro-spinning, with waste management and wastewater treatment. The study proposes a fiber bottle production model that consists of a single waste supplier and a single fiber bottle producer operating within a circular framework. The model takes into consideration green investment, waste management, and water treatment to reduce waste bottles from the fiber industry. The effect of emission reduction technology and waste minimization technology with carbon cap policy are studied, and found that the industry benefits from investments in green technology and waste minimization technology by generating 8.076% more profit while less emissions and waste through r-PET compared to virgin PET. The numerical example has been provided to illustrate the optimization procedure for finding the optimal solution. Sensitivity analysis and managerial framework in the petrochemical industry are presented to observe the changes in decision variables when key parameters are changed. The study concludes that the implementation of the reuse, recycle, and reduce the concept of circularity for the end-of-life processing with life cycle assessment and material recovery. Upcycling PET waste bottles into high-values-added products may enhance the supply chain profit with less pollution, which is the ultimate goal of a sustainable economic model. [Display omitted] • Environmental impacts of PET waste control and emission reduction are employed. • Recycled PET waste in the production of sustainable fibre and other value-added products. • Electrospinning techniques and wastewater treatment through nanofiber are studied. • Reduction of PET waste plastics from the fibre industry gets more profit. [ABSTRACT FROM AUTHOR]

Managing waste and promoting a transition to a resource-efficient economy are key elements of the European environmental policy. This research aims to explore waste transport's environmental relevance and assess how to operationalize inter-territorial cooperation for waste management. This study develops a lifecycle-based indicator to analyze and compare three alternative scenarios for residual waste flow planning. Results indicate that the incidence of transport is relevant to the point that, if not considered, it can lead to ineffective decisions. • A residual solid waste flow planning process at the regional level is analyzed. • The subject of this study are three alternative landfills in the same region. • The landfills under study are in different districts. • The lifecycle assessment method is used to develop a lifecycle-based indicator. • Burdens of waste transport are so relevant that they always need to be considered. [ABSTRACT FROM AUTHOR]

Many waste LCA models are available for waste management decision and policy makers to better manage their waste streams. These models contain inherent differences in their functionality (e.g., LCI, LCIA, technical assumptions), which creates complications for non-expert LCA users to interpret results. Here, we present a unique approach to identify crucial model similarities and differences by conducting scenario runs and comparing the results in the context of waste management decision making. Five waste LCA models were evaluated, the model defaults for the LCI, LCIA, and technical assumptions related to recycling, landfilling, and combustion were used. The recycling/combustion default assumptions were relatively similar amongst models compared to their landfill defaults. For recycling, the assumption of a forest carbon credit for paper products (applied in WARM) resulted in an environmental offset and in different outcomes than other models. The major differences for landfilling resulted from landfill gas management and energy recovery defaults, with MSW-DST associated with the most conservative collection efficiencies and no energy conversion which resulted in the greatest environmental footprints compared to other models, especially SWOLF and EASETECH. While for combustion the major difference amongst models was the inclusion of non-ferrous metal ash recovery. Overall, the models agreed the most environmental favorable results were to combust paper and organic materials and recycle plastics, glass, and metals. The results here assist waste management decision makers, who are typically non-expert LCA users, to gain a greater understanding of the major differences/similarities in their LCA study when using multiple models and better decide which model's functionality aligns best with their goals and scope. Expert LCA practitioners can use the study results to identify areas needing data collection, and to facilitate discussion about the acceptance of, or lack of, important technical assumptions. • Five waste LCA models were evaluated for defaults assumptions. • Assumption of a forest carbon credit for paper products is important in recycling. • Major differences for landfilling resulted from landfill gas management defaults. • Models agreed most environmental favorable is to recycle. • Results used to facilitate discussion about standardizing technical assumptions. [ABSTRACT FROM AUTHOR]

This article presents the abstract of the paper Economic and Environmental Analysis of the Wine Bottle Production in Spain by Means of Life Cycle Assessment, which appeared in the 2005 issue of the International Journal of Agricultural Resources, Governance and Ecology. The paper's objective is to analyse the improvements obtained by the implementation of eco-efficiency in wine production. The principal aim is to achieve the rational energy and materials consumption in the whole wine production process implementing the Life Cycle Analysis (LCA) methodology. The production processes and the products are analysed taking into account their LCA from the raw materials and the intermediate process products, to the final product, the waste and the emissions generated. Their possible re-utilisation and the process integration are also analysed in order to minimise the load pollutant. Through LCA, energy, material requirements and waste are identified and described quantitatively for each process. Moreover the associated impacts are evaluated and explained identifying the processes with higher improvement potential. Finally the innovative solutions implemented for eco-efficient wine production are described and analysed.

This article presents the abstract of the paper LCA and Tomato Production in Mediterranean Greenhouses, which appeared in the 2005 issue of the International Journal of Agricultural Resources, Governance and Ecology. Life cycle analysis is used to analyse and evaluate the environmental impact associated with the process of greenhouse cultivation of tomato crop. Tomato production in kilogram is selected as a functional unit. Three different tomato production processes were compared: soil cultivation and open and closed hydroponic systems. Three different waste management scenarios were also analysed. The most significant negative environmental impacts were identified, enabling the application of the most suitable technology in order to mitigate their effects. The main negative impact of greenhouse tomato production derives from the waste of biomass and plastics, therefore suitable waste management is the best practicable environmental option to reduce this. The composting of biodegradable matter is the best way of managing this kind of waste. Improving the material composition of structures and auxiliary materials is also advised. Lastly, more rational management criteria for the supply of nutrients to the crop will have to be found.