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The production of CaO for lime-based plaster and render generates 1.2 t CO 2 /t CaO, consumes 1.78 t CaCO 3 /t CaO. This research paper examines the environmental and economic performance of upcycling paper mill sludge (PMS) and carbide lime (CL) as replacements for hydrated lime (HL) in lime-based plasters production. For this, a new Cradle-to-Gate industrial-scale inventory is designed, upscaling recent lab-scale innovations, investigating PMS and CL treatment processes, followed by a Cradle-to-Grave scenario analysis. The results show that incorporating CL in the plaster yields better environmental and economic outcomes compared to PMS. The intermediate treatment for CL is cost-effective and has low carbon emissions. The upcycling of CL eliminates 100% of CO 2 emissions, while PMS reduces emissions by 11%. The production of the traditional binder HL is more expensive than upcycling PMS (+69%) and CL (+65%), with carbon taxes accounting for 35%, 44% and 15% of production costs, respectively. The effect of an equilibrated carbon price to ensure fair market competition, considering the natural carbonation of lime (carbon credit) is discussed, and the cost assessment reveals a 47% and 54% reduction for upcycled plasters using PMS and CL, respectively, compared to traditional HL. [Display omitted] • Availability, properties, and treatments of secondary lime resources. • Industrial-scale inventory for upcycling carbide lime (CL) & paper sludge (PS). • Cradle-to-Grave assessment: CL reduces CO 2 most, trailed by PS and hydrated lime. • Key factors for Cradle-to-Grave impact: lime kiln heat consumption (PS) and drying operation (CL). • Cost analysis of carbon taxes and credits across the material's life-cycle. [ABSTRACT FROM AUTHOR]

This paper describes the role of Design Thinking (DT) in the context of sustainable development (SD), based on a perceived research need to identify the features which may characterise its deployment, and identify ways via which it may be optimised, especially in the implementation of the United Nations Sustainable Development Goals (UN SDGs). The main goal of this study is to examine the connection between DT and SD and showcase examples of what has been done to deploy it, using real-case situations. From a methodological perspective, the paper deploys a set of two methods: bibliometric analysis and case studies. Among other findings, the paper shows that DT can be used to help implement the UN SDGs by providing an approach that emphasizes human-centered design. This includes identifying problems, creating user-friendly solutions, and testing them in order to ensure that they are effective. Also, by using DT, companies, organisations, and governments can create low-cost, high-impact, and sustainable solutions to help achieve SDGs such as SDG8, SDG9, SDG12, and SDG13, among others. Overall, DT provides a framework for combining creative and analytical reasoning, specific mindsets, and diverse hands-on tools and techniques to improve critical thinking abilities towards sustainability challenges. The novelty of the paper relies on the fact that the combined use of the two methods allowed the identification of some useful features of DT, which may facilitate its deployment in sustainability contexts. This may assist future studies since it provides a theoretical basis for the field. • Research gaps in DT prevent its widespread use in SD. • The paper deploys bibliometric analysis and case studies. • DT within a circular economy is an emerging approach. • DT may foster sustainability practices. • A novelty is the identification of pathways to optimise DT in SD. [ABSTRACT FROM AUTHOR]

Hospitals in the Netherlands generate approximately 1.3 million kg of waste from the polypropylene (PP) wrapping paper (WP) used to wrap surgical instruments each year. The aim of this study was to develop a method to recycle WP waste into new medical devices. WP was recovered from Maasstad Hospital, Netherlands. The WP was melted into bars, granulated, and mixed with virgin material at different ratios and temperatures. Dog bones were injection-molded from volume (v.%) virgin, mixed (%R), and recycled (100%R) granulate, and a tensile testing machine was used to compare the material properties before and after ten disinfection cycles at the sterilization department. Then, 25 instrument openers were made from the 50%R material and circulated for four weeks. The data indicated no significant differences in the mechanical properties at different melting temperatures. For dog bones made from the 100%R, 50%R, and virgin granulate, the Young's moduli were 1021 (SD13), 879 (SD13), and 795 (SD14) MPa, and the strains were 8%, 12%, and 14%. Ten disinfection cycles did not significantly change the material properties. After one month, the openers did not show any deterioration or damage other than surface scratches. The results indicated that the initial WP melting temperature did not influence the mechanical properties. Although devices could be produced directly from the recycled WP granulate, increasing the recycled granulate in the mix ratio increased the strength and brittleness. It is feasible to recycle WP waste into a high-quality raw material for the injection molding of medical devices without using additives. This would allow hospitals to become more compliant with the circular economy enabling economically viable and circular processes that positively contribute to cleaner technical processes, sustainable products, and the reduction of medical waste. ⁃ Circular reprocessing of surgical waste into high quality raw material. ⁃ Enables cleaner processes for reduction of medical waste. ⁃ Increases sustainable development. ⁃ A new method to decrease the production of medical waste. ⁃ Decreases the shortage of base materials and costs. ⁃ Environmental and sustainability assessment: designs for products based on the "green" wishes of customers. [ABSTRACT FROM AUTHOR]

The 17 Sustainable Development Goals (SDGs) defined by the United Nations represent a blueprint for the adoption of global practices and policies to foster sustainability in societies and increase efficiencies in resources uses. The Italian National Trust, FAI, has embraced these goals, developing a holistic and transdisciplinary methodology to promote a more sustainable approach to preserve its natural and built heritage. This methodology combines heritage protection with the SDGs in various macro-areas of interventions, including energy, water, biosphere, responsible consumption, and sustainable communities. The aim is to increase access to affordable and clean energy, reduce water, waste, and soil footprints, promote responsible consumption, and develop human capital. The paper proposes a set of strategies to achieve the SDGs in heritage, involving the collaboration of several stakeholders, ranging from institutions to citizens. The methodology is applied to a specific Italian case study, Casa Macchi in Morazzone, to highlight the challenges in achieving the dual objective of preserving the historic building and promoting sustainability in the built environment. [Display omitted] • We propose a trans-disciplinary methodology for sustainable heritage preservation. • The heritage preservation project is analyzed in five macro-areas of intervention. • Assessment of effects on energy, water, biosphere, resources, and sustainability. • Casa Macchi preservation project to apply methodology and prove effectiveness. [ABSTRACT FROM AUTHOR]

Emerging industries and technologies are made up of objective, practical requirements and ideas that encompass broad hopes for what future newness might enable. The bioeconomy is one such emerging industry. Its recent evolution has involved a complicated and dynamic mix of promises, reality checks and subsequent ambivalences. This article frames and investigates the emerging algae-based bioplastics industry as one niche within this broader system envisaged for social, technological, economic, political and ecological change. As such, our paper presents two categories of knowledge that in practice interrelate: 1) specific and practical recommendations that can assist a future algal-based bioplastics industry to develop in Australia in ways that are conscious of socio-ecological and socio-cultural dimensions, and 2) critical extensions that go beyond the attributes of newness, impact, suddenness and universality often emphasised in both popular and scientific research into emerging green technologies. In particular, our analysis highlights the importance of specific temporal, tonal and spatial factors when framing the contextual factors associated emerging industries, technologies and the different pathways for change they might help support. • Pathways and enabling factors for a algal-based bioplastics industry in regional Australia are presented. • The 'social idea' of the bioeconomy is analysed with reference to algal-based bioplastics. • The algal-based bioplastics industry is contextualised in relation to transition pathways literatureon the bioeconomy. • Themes and recommendations are synthesised from literature review and semi-structured interviews. [ABSTRACT FROM AUTHOR]

Circular Economy (CE) is a promising solution for a wide range of stakeholders, including companies, governments, and society at large to confront serious environmental concerns (Crome et al., 2023) to address resource depletion, environmental degradation, and waste generation. As Cambodia's economy heavily relies on resource extraction and export-oriented industries (e.g., textile industry and agriculture contributing significantly to GDP), it generates substantial waste (fundamentally, Municipal Solid Waste (MSW), but also industrial, construction and demolition waste (UNDP, 2022a,b)), and pollution. To tackle such issues, the government has recently demonstrated a stronger commitment to sustainable development by integrating CE principles into a national policy. First, this paper explores the current environmental issues of the country. Secondly, it assessed the country's CE Strategy and Action Plan. Thirdly, as a primary finding, it was discussed the potential barriers, international collaboration prospects, and implementation recommendations to catalyze challenges into opportunities, covering the gaps observed in the country's CE Strategy and Action Plan, and following prominent CE trends. Lastly, it concludes that despite the hurdles, CE has the potential in the country to provide socio-economic benefits, including job creation, resilience, reduced reliance on imports, and improved public health. This paper consisting of policy analysis combined with a bibliographical review presumably represents the first work on this topic; it will be useful for foreign investors, academia, and policymakers. • A contemporary analysis of the most noteworthy environmental issues in Cambodia. • Policy adoption assessment of Cambodia's Circular Economy Strategy and Action Plan. • Discussion with barriers, international opportunities, and recommendations. [ABSTRACT FROM AUTHOR]

Sustainable development and reducing natural and energy resource consumption are the focus of the policies of many institutions. In this context, livestock farming is one of the major anthropogenic sources of GHG and acidifying gas emissions and requires comprehensive analysis to minimise its ecological footprint. For this reason, it is beneficial to analyse the various processes within this production sector to reduce the consumption of resources, particularly water and soil consumption; reduce energy consumption; and try to valorise the biowaste produced, especially manure, byproducts and wastewater. Reusing residual bioresource and organic waste offers the possibility of valorising a discarded product and, at the same time, reducing the consumption of natural resources. For this purpose, biorefinery processes allow bioresources to be transformed into bioproducts or bioenergy. Therefore, this study investigates the application of biorefinery processes to animal-derived waste, aiming to extract valuable resources while curbing resource consumption. This review analysed 293 scientific papers on biorefinery processes published in the last 11 years applied to livestock biomass to extract relevant information to understand the evolution of this topic and formulate hypotheses regarding future research directions. The analysis strongly emphasizes energy production and a growing interest in insect cultivation. In the coming years, one of the most significant challenges will be the successful transfer of technologies and processes from experimental research to the applied industry. To do this, it will be necessary to reduce costs, exploit economies of scale, improve process management, and develop synergies between different industrial sectors to implement smart circular economy systems. Overall, this review aims to clarify the hypothesis driving research in this area and emphasizes the tangible applications of findings within the broader context of sustainable resource management. [Display omitted] [ABSTRACT FROM AUTHOR]

Industrial Symbiosis (IS) projects are today well known for their contribution to sustainable development. Designing IS projects implies modelling the quantity of material flows between economic components (ECs), in particular to evaluate the environmental and economic gains obtained through more material circularity and use efficiency. The Industrial Symbiosis concept is now being applied to activities distributed over territories much wider than industrial parks. For such setups, existing modelling methods are becoming strained by the number of economic components involved, their dissemination within heterogeneous landscapes and the resulting complexity of the exchanges. In this paper, we propose a generic, spatially explicit simulation model based on stakeholder decision rules to study regional scale flows quantification between ECs in n-n IS networks. Our approach introduces the use of the Gale-Shapley stable matching algorithm for addressing the many-to-many supply-demand matching problem. The method is deterministic and provides stable solutions that optimise the individual objectives of the ECs. A second introduction considers using transport cost along the road network among the decision rules when ECs preferences are ordered. This solves the issue of correctly estimating travel distance in heterogeneous landscapes where it can be significantly different to the distance as the crow flies. We tested the model with the implementation of two real and concrete case studies related to the bioeconomy of a tropical island: (i) collective storage of fodder and (ii) co-composting platforms. The outputs of the model make it possible to compare scenarios based on EC satisfaction relative to supply and demand as well as the total distance travelled along the road network. Finally, we discuss the limitations and genericity of the model to explore diverse industrial symbiosis projects. • Industrial symbiosis material flow modelled using stakeholder decision rules. • Our approach is spatially explicit, determinist and based on interactions. • Stable deferred acceptance matching algorithm used to link economic components. • Decision rules incorporate transport costs estimated based on the road network. • Model tested in n-n networks involving several thousand components at regional scale. [ABSTRACT FROM AUTHOR]

To promote their public image, a growing number of companies have adopted corporate social responsibility (CSR) projects that benefit various social interests. As such, it is imperative to audit the social, environmental, and economic dimensions of CSR projects for their sustainable development. This paper presents an assessment of three CSR projects undertaken by the energy industry (renewable energy) and commercial sector (plastic waste recycling) in Thailand to transition towards the circular economy (CE) business model. A set of CE indicators were selected from the World Business Council for Sustainable Development: WBCSD 2018 European Commission 2018, and British Standard Institution 2017 and compared with the sustainability indicators listed in the ISO 26000:2010 (referenced in the Global Reporting Initiative (GRI): G4 Guidelines). These indicators were established to assess the readiness of companies to implement sustainable CSR projects. The assessment results showed that the CSR projects in the case study were conducive to the CE model, as most of the CE concepts evaluated by the performance indicators were already in place. This study aimed to support the implementation of CSR projects that contribute to adopting a CE business model and determine key performance indicators (KPIs) to measure and monitor CSR projects in terms of their CE concepts. The sustainability KPIs proposed in this study can serve as a set of guidelines to drive CE strategy adoption and allow for the identification of sustainable CSR projects that can simultaneously offer more value creation and satisfaction for all stakeholders, including society and the companies, while reducing environmental impacts. This paper integrates CSR into a CE approach that results in business sustainability and contributes to Sustainability Development Goal (SDG) targets. [Display omitted] • KPIs were adopted for the comprehensive assessment of CSR projects. • CSR projects of renewable energy and plastic waste were evaluated in their ability to CE concepts. • The KPIs can identify sustainable level and contribute to CE and SDG targets of businesses. [ABSTRACT FROM AUTHOR]

In recent years, the Circular Economy (CE) has gained attention as a strategy for achieving sustainable development through cleaner production and reducing waste and pollution. At the same time, digital technologies are recognized as crucial sustainability drivers by enabling efficiency, collaboration, and innovation. This research paper explores the factors that support Green Entrepreneurship (GE) and digitalization in the context of CE and Waste Management (WM) in Indian manufacturing "Micro, Small, and Medium Enterprises" (MSMEs). Further, the study prioritizes, establishes a contextual relationship, and clusters the GE factors that enable digitalization in the CE and WM of Indian manufacturing MSMEs. To meet research goals, the study uses a mixed-methods approach that includes a literature review, qualitative interviews with MSME managers, and theoretical support (stakeholder theory, resource-based view, dynamic capability theory, met expectation theory, and upper echelons theory) to find the enablers. Further, two-phase "Multi-Criteria Decision Making" (MCDM) tools are utilized. Initially, the quantitative "Best-Worst Method" (BWM) was used for ranking, and then "Total Interpretive Structural Modeling" (TISM) was used to establish a mutual relationship among the enablers. The strength of relationships among the enablers was established based on "dependence power" (DEP) and "driving power" (DRP). The findings through BWM analysis show that among the main category, technology-based enablers, and among sub-categories, top management and organizational coordination are the high-priority enablers/sub-enablers to optimize sustainable action. The findings also suggest that technology infrastructure for cleaner and sustainable manufacturing, knowledge of green entrepreneurs, training, the dynamic capacities of digitalization towards a CE, subsidies, and finance are driving enablers. The research contributes to understanding the enabling factors of GE and digitalization and their interdependencies for CE and sustainable development. [Display omitted] • Green Entrepreneurship and Digitalization drive Sustainable Waste Management and Circular Economy. • Top management and organizational coordination are crucial for sustainable action. • Infrastructure and knowledge drive digitalization in the Circular Economy. • Digitalization and green entrepreneurship complement the circular economy. [ABSTRACT FROM AUTHOR]

Rapid population growth and urbanisation have accelerated waste generation, and effective waste management has become a major challenge worldwide. With advances in technology and management methods, waste management strategies have begun embracing digitalisation, leveraging the Internet of Things (IoT), big data analytics, cloud/edge computing, machine learning, 5G communication, and blockchain technologies. Amongst them, the blockchain technology has the structural features of achieving information security and integrity without central guarantees. Blockchain also meets the data record/storage needs of waste management and the design of new mechanisms for effective waste management. These benefits make blockchain an attractive technology in the field of waste management, with researchers and practitioners alike investigating its broad applications to support sustainable waste management. However, this emerging technology has not yet been widely accepted by potential users. To further champion the application of blockchain technology, this review paper provides a systematic overview of the various pathways in which the technology has been applied in the waste management industry and further discusses its related challenges and opportunities via considering the promising prospect of combining blockchain technology with IoT, artificial intelligence (AI) and life cycle assessment (LCA). This review also provides insights for interpreting some emerging applications of blockchain in the field of waste management and clarifying the research paths in the context of blockchain, digitalised waste management, and circular economy. [Display omitted] • Impacts of blockchain technology on waste management have been substantial. • Recent development from blockchain's functional perspectives was surveyed. • There is a long way towards blockchain-based sustainable waste management. • Relevant challenges and opportunities in blockchain applications were discussed. • Outlooks in digitalised waste management and circular economy were clarified. [ABSTRACT FROM AUTHOR]

In recent years, sustainability concerns gained traction in the scientific literature on cleaner production, as well as in industry and application. In this regard, the circular economy (CE) is intended to contribute to the current ecological transition, providing economic advantages and preserving global society for future generations. CE initiatives have been implemented in recent decades to offset the harmful environmental consequences of supply chain operations. Notably, CE strategies can be applied at different supply chain levels, in product design, manufacturing, transportation, consumption, and disposal. Using the Life Cycle Assessment (LCA) methodology, the present research examines a case study from the Italian egg industry, highlighting the environmental benefits and social implications of initiatives supporting CE (i.e. the use of recyclable and biodegradable packaging and the adoption of a short supply chain). The implementation of those CE strategies shows a 22% reduction in Kg CO 2 -eq emissions, proposing that circular concepts should be incorporated into sustainable supply chain management. Notably, this paper analyses the environmental implications of the intermediate phases of the egg industry supply chain. Both primary and secondary data have been collected. We collected primary data via direct interviews with companies' managers throughout all the study phases. As a result, despite various external issues affecting the company decisions, the paper shows that incorporating CE strategies may deliver demonstrable environmental benefits for the companies. In addition, other strategies that should be adopted in the long term have also been outlined. Finally, the implications that sustainable behaviours of the companies can entail have been examined. [ABSTRACT FROM AUTHOR]

Circular economy is a sustainable economic development model. It replaces the traditional economic development model that relies heavily on resource consumption and waste generation. Circular economy is particularly important to the waste electrical and electronic equipment industry as e-waste contains toxic substances and precious metals. While previous review studies focused on specific aspects of the WEEE industry (e.g., "4R" circular economy strategies), these studies offer little details on how circular economy practices affect the development of the environment and economy in the waste electrical and electronic equipment industry. This study examines "10R" circular economy strategies to advance knowledge of the existing literature that focuses on "4R" circular economy strategies. To improve the methodology used in the previous review studies that apply subjective methods (e.g., content analysis), this paper conducts a systematic literature review on 208 studies and uses citation network analysis to examine specific circular economy practices in the waste electrical and electronic equipment industry. The citation network analysis identified five major research domains (i.e., "e-waste management systems and practices", "e-waste legislation and its components", "extended producer responsibility schemes", "recycling critical materials from e-waste", "circular economy strategies for the waste electrical and electronic equipment industry"). Based on these results, this study conducts a main path analysis to reveal ten major topics (i.e., e-waste recycling system; exploring untapped e-waste; compliance assurance of stakeholders; e-waste reverse logistics; reward and punishment mechanisms in extended producer responsibility system; verifying the rationality of product classification; recycling critical materials from urban mines; setting a specific target for preparation for reuse; "10R" strategies applied in the smart factory; consumer attitude toward remanufactured/refurbished/repurposed strategies and the resultant products) in the identified research domain. Finally, this paper proposes future research directions and provides managerial and policy implications for researchers and practitioners. • "10R" strategies for the waste electrical and electronic equipment industry. • Effect of circular economy practices on environmental and economic performance. • Related publications evolution characteristics in 2003–2020. • Five key research domains of circular economy practices and their major topics. • Research directions for future studies. [ABSTRACT FROM AUTHOR]

Contemporary concepts of economic development in the European Union (EU) progressively focus on environmental protection. At the stage of their implementation by the EU countries, some of the policies include sustainable development, green growth, green economy, and circular economy. The leading concept in this regard is the European Green Deal. It should be noted, that a multitude of means exists within EU countries, by which plastic waste is managed, with a significant share of countries largely landfilling it or placing it in waste storage facilities. The aim of this paper is to introduce a proposal meant to propel the prospects related to managing plastic waste through chemical recycling. This recommendation would contribute to the fulfillment of the circular economy model implemented by EU countries. By means of chemical recycling, it is possible to transform plastic waste into a full-value market product which can be used, for example, in the fuel industry, constituting an alternative to the agricultural products used (biocomponents). Thereby, it may result in the production of, for example, engine fuel components that can replace plant-based components or other added-value chemicals. The findings demonstrated on four levels: environmental, technical, economic, and managerial, confirm the technological possibilities of chemical recycling of plastics and the legitimacy of the implementation of the presented concept. [ABSTRACT FROM AUTHOR]

This VSI focuses on what cross-cutting insights might be gained from research to increase the energy/materials circularity and the contribution of eco-innovation, cleaner consumption, and waste management to produce a logical body of knowledge that may lead to increased resilience and a sustainable Planet. The articles' collection shows development trends of sustainable, cleaner production under the Special Issue: A Resilient and Sustainable World. Some selected d papers have been presented and emerged from the 10th and 11th International Workshop on Advances in Cleaner Production (IWACP), held in hybrid mode in Italy (Ferrata and Florence). The contribution of the articles in this Special Issue could be divided into efforts toward sustainable and cleaner production, aiming (i) Eco-innovation for cleaner production and circular economy, (ii) Proper monitoring and identification of cleaner production, circular economy, and eco-innovation, (iii) cleaner production, circular economy and eco-innovation targeting social wellbeing and cleaner environment, (iv) cleaner production, circular economy and eco-innovation targeting emission reduction, and (v) cleaner production, circular economy and eco-innovation targeting improved and optimized production processes. [ABSTRACT FROM AUTHOR]

We need a proper mechanism to manage issues related to our environment, economy, and society to proceed toward sustainability. Many researchers have worked for sustainable development goals using artificial intelligence (AI) and machine learning to develop an efficient mechanism to facilitate a circular economy and link up the needs of the present generation without disconcerting the capability of coming generations. This study offers a comprehensive review of AI and sustainability and suggested future research scope. The review has focused on different use cases in industries like construction, transportation, healthcare, manufacturing, agriculture, and water. The systematic review is based on 287 papers selected out of 8341 search results with an application of PRISMA based method. Out of all the techniques used in sustainability regression, RL and DSS-based AI models are more popular than others. The review also provides directions surrounding which industrial sectors are using which methods for incorporating sustainable development practices in their organization. • We analyzed the impact of Artificial Intelligence on Sustainability. • A PRISMA based method is used for undertaking this literature review. • Areas covered in this study are environmental causes, technical challenges, and social issues. • Various AI algorithms used till now for achieving sustainability has been presented. • We present future research directions for use of AI for sustainable development. [ABSTRACT FROM AUTHOR]

Post-occupancy evaluation (POE) enables designers and contractors to determine whether a building's performance 'in-use' meets the specifications prescribed 'in-design'. Hence, POE presents an invaluable opportunity for stakeholders within the architecture, engineering, construction and operations (AECO) sector to learn from mistakes and improve the environmental performance of future designs. Against this contextual backdrop, this paper identifies the barriers to performing a POE implementation following a building's hand-over and use, and how these barriers inadvertently prevent sustainable development goals from being reached. A theoretical model is developed which enables building owners and users to implement a POE and thereby realise its innate potential to reduce the impact of the built environment upon the natural environment. An interpretivist philosophical stance is adopted to analyse both secondary and primary data collated using a three-stage waterfall process. First, a thematic content analysis is conducted utilising the transcript of a practitioner focus group convened to garner perspectives on the prominent barriers to POE implementation. Second, a scientometric analysis is undertaken to examine the prevailing body of knowledge (BoK) pertaining to sustainability, circular economy and barriers to POE implementation. Finally, a cross-comparative analysis of the emergent findings emanating from the previous two stages is conducted to ascertain whether academic literature is addressing the barriers identified by industry practitioners. The research reveals that despite the significant opportunities that POE presents to reduce the built environment's substantial impact upon the natural environment, only a relatively small proportion of the POE BoK explores this objective. Similarly, an even smaller proportion of literature examines the barriers to POE implementation and how to overcome them. The cross-comparative analysis undertaken highlights inconsistencies between practitioner requirements regarding implementation barriers and the proportion of the POE BoK pursuing this objective. Curiously, there is no literature delineating POE's potential to facilitate a circular economy within the built environment sector. A novel theoretical model emerges from this research which acts to bridge a gap between theory and practice and provides utility for researchers and practitioners alike to increase the interchange of knowledge pertaining to pertinent POE requirements. The resultant model establishes POE as a crucial environmental feedback mechanism for stakeholders within the AECO sector. [ABSTRACT FROM AUTHOR]

Anaerobic digestion of bioplastics' wastes may represent a valuable disposal strategy for these important substitutes for plastics, in order to reduce their leakage into the environment and to produce bioenergy in the form of biomethane, contributing positively to the sustainability of the entire bioplastics' life chain. Only lab-scale data about bioplastics' anaerobic degradability and biomethane production have been produced until now, using approaches far from full-scale conditions. This paper presents a novel approach in studying the potential of bioplastics to produce biomethane because a pioneering methodology was adopted, allowing acquisition of full-scale data that can be useful to further attest environmental and economic sustainability in recovering bioplastics' wastes. A simple and replicable experimental approach was proposed to studying bioplastic degradability during anaerobic digestion, which consisted of placing the bioplastics into a full-scale digester within perforated steel boxes. Three different bioplastics items (one starch-based and two polylactic-acid based) were co-digested with organic wastes in a real anaerobic digestion plant using the real process parameters (thermophilic temperature for 30 days of hydraulic retention time followed by 30 days of mesophilic maturation). The experiments were replicated at laboratory-scale to evaluate the potential for biomethane recovery from bioplastics degradation. Laboratory-scale data did not differ from the data coming from the full-scale experiment, i.e., bioplastic degradation was not affected by the reactor volume. Bioplastics showed an average degradation of 27 ± 5% on a weight basis and a different degradation mechanism for the two types studied was found through Fourier Transform-InfraRed spectroscopy (FTIR) analysis. Starch-based bioplastics showed a quick consumption of the starch component, followed by a slow degradation of the polyester fraction. Polylactic acid bioplastics were degraded without chemical changes to their composition. In both laboratory-scale and full-scale experiments, temperature was a key parameter affecting bioplastics' degradation, i.e., thermophilic temperatures were needed to obtain a significant degradation. Biomethane potential determination of the bioplastics (135 ± 23 NLCH 4 kg Volatile Solids−1 as average at the end of the thermophilic digestion) proved that anaerobic digestion of bioplastics may be a sustainable approach, reducing bioplastic leakage and producing bioenergy (biogas), respecting Circular Economy principles. Anaerobic digestion may represent a valorisation treatment for bioplastics' wastes contributing positively to the sustainability of the entire bioplastics' life chain. [Display omitted] • First assessment of bioplastics' anaerobic degradation using a full-scale approach. • Starch-based and polylactic acid-based bioplastics degrade differently during AD. • Bioplastics' anaerobic degradation may enhance biomethane production from AD plant. • AD of bioplastics can avoid their leakage into natural environments. [ABSTRACT FROM AUTHOR]

Mismanaged plastic waste is a major environmental concern, especially in countries of the Global South. Municipal solid waste management can not only alleviate environmental problems but also create jobs and promote local economic growth. However, providing appropriate waste management services is costly. The question is to what extent waste management policies that have proven to be successful in other geographies can help solve the challenge in developing countries. Specifically, the economics and financial flows along the value chain need to be known. In this paper, we shed light on these questions by presenting a novel, model-based method to elicit and assess the cost structure of the recycling sector in developing countries. We exemplify our method with plastics waste management in the Greater Accra Region of Ghana—an area particularly challenged by plastic waste. For this purpose, we surveyed over 80 participants of the waste management value chain and combined the data with insights from expert interviews and workshops. Based on this data, we built a bottom-up model with 67 parameters, reflecting all cost positions in the waste management value chain. We found that street waste pickers are the poorest and most vulnerable, earning only a fraction of the already low minimum wage. Middlemen and aggregators, while often being criticized for their earnings, also provide social-security-like services to waste pickers. In addition, formal and informal recyclers differ not only in earnings and size but also in recyclate quality where the informal sector provides higher quality. [Display omitted] • Analysis of formal & informal plastic waste management value chain in Accra, Ghana. • New bottom-up method for estimating & modelling true cost of waste management. • Waste pickers abstain from necessary safety equipment to achieve positive returns. • Formal recycling structures allow for scaling but reduce recyclate quality. • Substantial investments are needed to scale up recycling capacity and quality. [ABSTRACT FROM AUTHOR]