Circular Economy Initiatives Research Articles

Applying social life cycle assessment in the informal recycling sector: Understanding challenges and limitations

The transition towards Circular Economy (CE) is a promising approach to sustainable development that may cause significant social impacts. Despite the benefits of CE initiatives, key players such as informal recyclers face serious social issues such as poverty, lack of social security, and discrimination. Although evaluating social impacts remains a considerable challenge, Social Life Cycle Assessment (SLCA) is recognized as a suitable methodology with a life cycle perspective. While most SLCA experiences are conducted in the formal sector, it is important to consider the informal sector, which plays a crucial role in developing countries. This article presents an analysis of SLCA studies in informal recycling settings in order to identify the challenges and adjustments required for informal settings. The analysis is based on a literature review and a documentary review of a pilot application of SLCA in the informal recycling system in Cuenca, Ecuador. The results show that SLCA requires adaptation to be applied in informal settings. There are particular challenges in delineating boundaries due to the fuzzy nature and variability of informal activities. Tasks such as establishing specific indicators, developing reference scales and data collection, require careful planning and active stakeholder participation. For instance, indicators regarding Fair Salary or Working hours were adapted based on best practices. Furthermore, tasks such as verifying and disseminating results should be included in interpretation phases to generate long-term impacts and influence behaviors. The study underscores SLCA's multidimensional view but highlights the need for further standardization and adaptation for informal sectors.

Geopolymer Production From Waste Polyethylene Terephthalate and Glass For Clay Subgrade Stabilization

In this study, the efficacy of Polyethylene Terephthalate (PET) and Waste Glass Powder (WGP) as soil stabilizers was investigated to address the research questions and objectives. It examines the enhancement of mechanical strength of clayey subgrade soils sourced from Ogun state, Nigeria across varying proportions (5% −20%) including the potential cost analysis. Providing experimental insights into soil stabilization using PET individually and in combination with WGP-based geopolymers. Optimal stabilization was achieved at 5% PET, accompanied by 5%-20% WGP, and activated with a 2M NaOH solution. Results demonstrated enhanced mechanical strength with both stabilizers, with the combination of PET and WGP proving the most effective. Specifically, stabilization with 5% PET (1.18mm) WGP geopolymer, activated with 2% NaOH, yielded optimal results, exhibiting UCS values ranging from 180kN/m2 to 320kN/m2, surpassing cement-based stabilization (UCS value: 380kN/m2). Moreover, durability testing revealed significant improvements, with PET+WGP samples displaying a UCS mean of 259.4kN/m2, a weight of 89.67g, and a percent change in mean and weight of −25.79% and −25.86%, respectively, compared to cement-stabilized soil (UCS mean: 408.66 kN/m2, percent change: 2.15%, weight mean: 109.25g, percent change: -25.86%). Furthermore, PET+WGP exhibited a 125% increase in CBR compared to PET alone and a better cost reduction of $6,153,850,000.00 for 100km, highlighting its superior performance and cost reduction. The findings of this study hold significance for informed decision-making in material selection for road pavement works, offering an alternative method and contributing to Sustainable Development Goals and Circular Economy initiatives by advocating sustainable waste management and road infrastructure.

More-than-transactional circular economies: the café-urban farm nexus and emergent regional food waste circuits

ABSTRACT As governments encourage circular economy (CE) initiatives, markets for waste recirculation are taking shape. But implementation is in its infancy and material circuits are emergent. Early food waste CEs shaped by commercial players emphasise capital investment, routinised forms of waged labour, processing sites distant from food waste sources, and transactional relationships. Less well understood is the potential for vernacular circularity beyond market-based, transactional frames. This paper reports from a collaborative research exercise with a non-profit community farm in nonmetropolitan Australia, seeking to connect with cafés to access food waste for composting. Cafés are a nexus of production and consumption, ubiquitous in the contemporary multicultural Australian context, and therefore ideal for grassroots CEs. Ten local cafes participated, reviewing existing food waste practices, motivations for circularity, and contextual factors including the regional setting. We found that food waste circularity emerges via divergent pathways related to enterprise type and scale, environmental values of actors, place embeddedness, and local relationships. These pathways reflect the place-based attributes and diverse sustainability values of residents and businesses in the coastal, industrial city of Wollongong, where the study is based. Contrasting distant, transactional circuits, are more-than-transactional food waste pathways, developed by microscale actors shaping vernacular material flows and “hacking” public provision of Food Organic and Garden Organic (FOGO) waste services to mobilise environmental values and community relationships. Overlooked by “big policy” more-than-transactional relationships bind producers, intermediaries and consumers in closer loops and, in so doing, enrich place and facilitate an ethic of care for soil and land.

Correlation analysis and predicting modeling of pyrolysis gas based on landfill excavated waste pyrolysis characteristics

The contribution of excavated waste to waste management is multifaceted, including minimization, non-hazardous disposal, access to useable land resources, improved waste management techniques and public environmental awareness, consistent with recent circular economy initiatives. Pyrolysis can be converted into tar, pyrolysis gas and char with recyclable utilization, enriching the application of pyrolysis technology in the field of excavation waste. In this study, the pyrolysis system includes horizontal tube furnace, gas collection device and Micro GC. The excavated waste was pyrolyzed at a temperature of 500∼900 °C with a heating rate of 10 °C/min. Pyrolysis gases include H2, CO, CO2, CH4, C2H4, C2H6 and C3H8. Pyrolysis was divided into four stages, the main decomposition range is 230∼500 °C, with a weight loss rate of 68.49% and a co-pyrolysis behavior. As the temperature increases, the tar and char decreased and the gas production increased significantly, and the pyrolysis gas reached 47.02% at 900 °C. According to Pearson correlation coefficient analysis, the generation of H2 and CO is positively correlated with temperature. Therefore, the target products can be influenced by changing the parameters, when considering the practical utilization of the excavated waste pyrolysis products. On this basis, the prediction models were built by polynomial fitting method. This model can reduce the experimental exploration cycle, reduce the cost, and accurately predict the pyrolysis gas, which has practical guidance for the application of pyrolysis industry, and provides a theoretical basis for the resource recycling and energy recovery of landfill.

Green logistics and circular economy in alleviating CO2 emissions: Does waste generation and GDP growth matter in EU countries?

The integration of Green Logistics (GL) and Circular Economy (CE) have been recognized as critical concepts for achieving sustainable economic and environmental performance. However, there is a lack of understanding on the combine impacts of CE and GL in alleviating CO2 emissions in pioneering nations relying on these concepts. This study examines the role of CE and GL sustainable in curbing CO2 emissions of 13 developed European Union (EU) countries from 2000 to 2020. The neoclassical growth and IPAT models, including the pool mean autoregressive distributed lags (PMG-ARDL) and the vector error correction model (VECM) are employed to estimate the short- and long-run effects and heterogeneous causal relationships. The long-run results reveal that CE and GL can mitigate CO2 (carbon dioxide) emissions, while the generation of municipal waste (GMW) has negative impact on the environment. Moreover, the long-run relationship between economic growth, CE, GL, and GMW validates the Environmental Kuznets Curve (EKC) hypothesis. The study also confirms a bidirectional causality between CE, GL, and CO2 emissions over the long run. This study proposes a model for assessing the impact of CE and GL initiatives on environmental performance and sustainability in both pioneering developed regions and emerging economies yet to embrace green growth concepts.

Towards a territorialisation of the circular economy: the proximity of stakeholders and resources matters

Abstract This article explores the territorialisation of the circular economy (CE) and analyses how the geographical and organised proximities of stakeholders facilitate the mobilisation of local resources for CE projects. It focuses on two local CE initiatives in Quebec (Canada) and France, for which 70 semi-structured interviews were conducted. The results highlight the importance of tangible and intangible territorial resources and demonstrate that geographical and organised proximities are crucial to the success of these initiatives. The relational dynamic between local players, stimulated by a sense of belonging and shared values, encourages commitment to CE. Thus, our study showcases the territorialisation of CE and emphasises the conditions enabling such activities to take root locally. This study has significant political implications and suggests the crucial role that local authorities must play in the deployment of CE projects.

Bio-Composite Filaments Based on Poly(Lactic Acid) and Cocoa Bean Shell Waste for Fused Filament Fabrication (FFF): Production, Characterization and 3D Printing.

In this study, novel biocomposite filaments incorporating cocoa bean shell waste (CBSW) and poly(lactic acid) (PLA) were formulated for application in Fused Filament Fabrication (FFF) technology. CBSW, obtained from discarded chocolate processing remnants, was blended with PLA at concentrations of 5 and 10 wt.% to address the challenge of waste material disposal while offering eco-friendly composite biofilaments for FFF, thereby promoting resource conservation and supporting circular economy initiatives. A comprehensive analysis encompassing structural, morphological, thermal, and mechanical assessments of both raw materials and resultant products (filaments and 3D printed bars) was conducted. The findings reveal the presence of filler aggregates only in high concentrations of CBSW. However, no significant morphological or thermal changes were observed at either CBSW concentration (5 wt.% and 10 wt.%) and satisfactory printability was achieved. In addition, tensile tests on the 3D printed objects showed improved stiffness and load resistance in these samples at the highest CBSW concentrations. In addition, to demonstrate their practical application, several 3D prototypes (chocolate-shaped objects) were printed for presentation in the company's shop window as a chocolate alternative; while retaining the sensory properties of the original cocoa, the mechanical properties were improved compared to the base raw material. Future research will focus on evaluating indicators relevant to the preservation of the biocomposite's sensory properties and longevity.

Industrial clusters as a vehicle for circular economy transition: A case study of networks in four industrial clusters in Zimbabwe

Multiple stakeholder partnerships are required to attain a Circular Economy (CE). Circularity can be achieved through industrial clusters in geographical proximity to each other. This research aims to assess the effects of industrial clustering on the adoption of CE in Zimbabwe (Workington, Southerton, Willowvale and Stapleford) in order to develop strategies for strengthening the impact of collaboration on CE practices in industry. The Workington and Southerton clusters were assessed as a joint cluster due to regular joint programming, whereas Willowvale and Stapleford were assessed separately. Interviews, document reviews and site visits were undertaken at selected members within the industrial clusters to understand some CE initiatives being carried out. A waste auditing programme was evaluated, resulting in ecological and economic benefits. Whilst many organisations were located in clusters, not all of them participated in CE activities. The Workington-Southerton cluster consisted of twenty-five (25) active members mainly dominated by private sector organisations in the manufacturing sector whilst Willowvale cluster had four (4) active members and Stapleford had nine (9) active members from industry and community network at the time of assessment. The main types of industries included food and beverages, fertiliser, metal fabrication, cable manufacturing, seed processing. Engineering, transport and bone char production. Collaboration based on geographical proximity allowed the organisations to undertake training, capacity building, workshops and industrial symbiosis. Implementation of the Industrial Waste Auditing Project (IWAP) by the networks, facilitated adoption of CE measures and presented an opportunity of improved waste recycling. It is concluded that geographical proximity can be used as an opportunity to facilitate attainment of a Circular Economy, but on its own is not a determinant of network success. Deeper issues of legal status, governance, value adding activities and financial viability - determine the ultimate impact of industrial clusters. We conclude that due to geographical proximity, there are opportunities of promoting industrial symbiosis. However, these opportunities need financing, technical capacity, governance and external support. Theoretical contributions of the research relate to the need for hybrid financing models to support CE activities and governance frameworks that provide oversight on industrial clusters. Further theoretical contributions relate to the new forms association beyond idiosyncratic organisations and advancing the need for measurable effects of collaboration using hybrid financing. Our theoretical contributions reveal new insights in governance and ownership of networks, especially how this can affect the delivery of CE activities.

Integrated biorefinery approach for seaweed Sargassum fusiforme: A step towards green circular economy

This study aims to maximize the utilization of Sargassum fusiforme (SF), embedding the concept of a green circular economy. We developed a green extraction process using water and ultrasound assistance to extract high-value SF polysaccharides (SFPS). A 2k factorial design coupled with center points evaluated the curvature effect in the extraction process. Optimal extraction conditions were identified to be a mass-liquid ratio of 1:59 (w/v), an extraction temperature of 70 °C and time of 88 min, yielding 15.30 wt% SFPS, validated through experiments. SFPS demonstrated significant antioxidant capacity, indicated by their ferric ion reduction ability and superoxide anion scavenging ability. Post-extraction, the waste ethanol solution and SF residue were employed as feedstock for hydrothermal liquefaction (HTL), aiming to produce biocrude oil. We explored various parameters affecting the yield and quality of the resultant biocrude. The optimal HTL conditions for SF residue included a temperature of 280 °C and a reaction time of 45 min. The biocrude obtained using the waste solution exhibited higher carbon content (69.83%) and higher heating value (33.42 MJ/kg) compared to freshwater, indicating enhanced energy recovery (87.65% vs. 15.39%). Also, the presence of ethanol in waste solution facilitated a decrease in fatty acid content from 48.50% to 24.50%, while simultaneously increasing ester content from 6.37% to 35.54%, presumably due to the trans-esterification of fatty acids into esters. Utilizing the waste ethanol solution as HTL processing medium also led to a much lower greenhouse gas emissions (1714.0 kg CO2-eq) compared to that of freshwater (7735.4 kg CO2-eq) as evidenced by the life cycle assessment. This study's innovative approach not only valorizes the waste streams from SFPS extraction but also adds value by generating high-quality biocrude oil, offering practical solutions for waste reduction and resource recovery, fostering sustainable development and circular economy initiatives.

Circular economy and the hospitality industry: A comparison of the Netherlands and Indonesia

The concept and practice of the Circular Economy is a key response to sustainability concerns, pioneered by the manufacturing sector and mainly explored from a developed economy perspective. This leaves a gap in relation to other sectors and contexts. This research investigates the adoption of circular economy initiatives and barriers to their implementation in the hospitality sector in the Netherlands and Indonesia through a comparative case study. Findings suggest that businesses in the Netherlands are hindered by their prioritization of delivering quality service as well as insufficient access to information on actionable circular interventions. For Indonesia, the predominant barriers include weak infrastructure, lack of regulatory enforcement and facilitation, and a lack of education and mindset. Our results provide an emerging economy perspective to knowledge of the circular economy, an under explored area of research. We also provide insights into the application of the circular economy in the hospitality industry. We uncover new challenges, especially in the context of emerging economies, and are able to confirm the relevance of previously identified barriers to both emerging economy and hospitality industry contexts.

Are the circular economy initiatives achievable through digitalization, technological advancements, and renewable energy

AbstractThe study examines the role of digitalization, technology, and renewable energy on environmental footprint which aims to access the circular economy in Saudi Arabia. We used the quarterly data, from 1998 to 2020, which is simulated by using the Markov chain Monte Carlo method for empirical estimations. The findings have reported the significant and positive coefficients for economic complexity and digital economy. On contrary, the digital infrastructure and technological advancement have provided the significant and negative coefficients. The results of digitalization indicators are diverse, mentioning that digitalization needs to be subcategorized to conclude the appropriate relationship between digitalization and carbon economy. We further report the findings on the basis of Saudi Vision 2030, which are useful for policy suggestions. The outcomes of this study are useful to form the environmental policies based on circular economy. Moreover, the policymakers have to put more efforts in digitalizing the economy, which leads to minimize the environmental damages.

Entrepreneurship and Carbon Footprints in Sub-Saharan Africa

This study examines the impact of entrepreneurship on carbon footprints in sub-Saharan Africa (SSA). The study applied the generalised method of moments on the data sourced from the World Development indicators (WDI) and World Governance Indicators (WGI). Result shows that entrepreneurship has a negative but not statistically significant impact on carbon footprints in SSA. Furthermore, across SSA subregions, entrepreneurship has a positive and statistically significant impact on carbon footprints in Central Africa (0.052%) and Southern Africa (0.1914%), while entrepreneurship has a negative and statistically significant impact on carbon footprints in Eastern Africa (0.064%) and Western Africa (0.0273%). Based on findings, the study concludes that entrepreneurs can develop and promote clean technologies, renewable energy projects, circular economy initiatives, sustainable agriculture practices, green transport solutions, and educational programs to lower carbon footprints. This calls for collaboration between stakeholders to create an enabling environment for sustainable entrepreneurship and accelerate Africa's transition towards a low-carbon future. The findings of the study contribute to the policy dialogue for the actualisation of sustainable development goals of good health and wellbeing (SDG 3), clean water and sanitation (SDG 6), promotion of development-oriented policies that support productive activities, decent job creation and entrepreneurship (SDG 8.3); sustainable cities and communities (SDG 11), climate action (SGD 13), life below water (SDG14) and life on land (SDG 15), respectively.

Modelling a Decarbonization Agenda for Bembibre’s Industrial Park

The design of the Sustainable Strategy Agenda for the Bembibre industrial zone in the Bierzo region employing the Open-Source Energy Modeling System (OSeMOSYS) is presented. This municipality, which has been affected by the collapse of the coal mining industry, is at the epicentre of the reindustrialization and Just Transition (none left behind) initiatives of the Spanish government. Among the challenges to be tackled are the zone's entire decarbonization by 2030, the incorporation of circular economy initiatives, and the development of quality jobs that attract and retain new residents. To facilitate decision-making, different roadmaps have been evaluated, including the repurposing of an old coal mine galley as a reverse hydro storage system, the deployment of enterprises dedicated to the recycling of solar panels, and the incorporation of second-life batteries from electric vehicles as energy storage. Among the scenarios evaluated, the most complex turns out to be the most interesting. With an initial outlay of 190 M€, it incorporates a 210 MW photovoltaic park linked to a mixed storage system comprised of 0.25 GWh of reverse hydraulic systems and 68MWh of second life reconditioned batteries. About 850 jobs in the implementation stage and 70 more permanent in the exploitation phase are envisaged.

Smart disassembly cell for circularity: Turn industry 4.0 technologies for disassembly and recovery of components.

Circular Economy initiatives have introduced a solution demand for the treatment of End of Life (EoL) products, switching from shredding and material recycling to the recovery of modules/components that remain functional. The process needs product recovery and diagnostic, disassembly, and requalification. These tasks are today carried out by human labour due to their complexity and uncertainties concerning the working conditions of the received product. But it implies time and costs that hardly balance the economical balance in developed countries context. Human – Cobot collaborative disassembly are promising solution to overcome the uncertainties without compromising the flexibility and the rate of disassembly operation. The Smart Disassembly Cell for Circularity (SDC2) project aims to provide a semi–automated disassembly solution for EoL electronic products. This paper portrays the requirements for the implementation of a Human-Cobot collaborative cell for electronic products. The goal of this project is to implement a shared workplace where the robot and the worker can work in parallel or share a common task with safe interaction. A literature study on available solutions was made. From there, the study and implementation of the decision system, database and service platform started. This document describes the function of the database and decision system as well as the service platform to establish global communication. MySQL and Python with the FLASK package were used to frame the database and service platform, Genetic algorithm was implemented for providing the robotic disassembly planning solution. A case study using a personal computer and a Power inverter was conducted to verify the development in each stage. The systems are under development with an aim to provide a global disassembly cell which will be able to disassemble various products rather than focusing on a specific product.

Exploring the Mechanisms Underlying Firms’ Intent to Adopt Circular Business Models

Firms play a vital role in the transition towards a circular economy (CE). However, the number of firms implementing CE initiatives, or circular business models (CBMs—economic models based on CE principles), is currently small. In light of this, this study quantitatively assesses the critical factors that influence firms' intentions to adopt CBMs, with the theories of Planned Behavior and the Resource-based View providing the theoretical background. We applied the PLS-SEM to 321 firms and found that attitude and perceived behavioral control of firm owners/managers, as well as long-term orientation and social pressure of firms, significantly influence the intention to adopt CBMs, with perceived behavioral control emerging as the most influential factor. The findings also confirm that finance and knowledge have a crucial influence on firm owners'/managers' perceptions of the conditions necessary to undertake CBMs. Overall, then, the study provides sound policy implications and scholarly evidence to fill the relevant research gap, and in so doing contributes to ensuring a better transition towards a CE.

INOVAÇÃO E TENDÊNCIAS DE SUSTENTABILIDADE AMBIENTAL NA INDÚSTRIA DE FITAS ADESIVAS

The last few years have presented an optimistic scenario for the adhesive tape industry on international scale. However, producers are being challenged to keep their operational structure competitive. Market demands and regulatory requirements also add increasing pressure for more sustainable products and more efficient production logistics processes. In this context, the present work evaluates the state of the art in innovation and environmental sustainability trends in the adhesive tapesindustry. Such environmental sustainability evaluation comprehended water usage in production processes, use of renewable electricity, CO2 emissions, use of organic solvents, waste recycling from the production process and circular economy initiatives by the main producers in this industrial field. These indicators are those that have been worked on by companies in the market and are in line with studies being carried out in the academic field.

Circular Economy from a Consumer Perspective: Malaysia Versus Pakistan

The industrial revolution has fuelled excessive production and consumption of products to the extent that is decimating the environment. To mitigate this issue, the newly discovered procedure of ‘The Circular Economy’ is entrenched. This concept encourages new and innovative systems of production, consumption and disposal with less to no adverse effects on the environment. The topic of circular economy, however, has been hardly researched by marketing scholars. The present research, therefore, attempts to consider the consumer stance in the circular economy, while reflecting on 757 consumers in two developing circular nations. Analysis was performed to test the proposed model and the hypotheses. Results evince that circular economy accelerates resource regeneration for both nations such that individual social norms, attitude and concern for the ecosystem are more relatively important than appropriacy and the right to control how consumer perceived their intention which aligned with sustainability and circular economy initiatives.

Circular Economy Initiatives in Supply Chain: A Systematic Literature Review and Future Research Directions

The concept of a circular economy (CE) entails developing a closed-loop system that strives to reduce waste, which adversely impacts the environment, while also minimising the use of resources (both natural and technical). The authors perform a thorough literature assessment of relevant papers using bibliometric and network analysis methodologies to identify the major components involved in a CE and solve the issues associated with implementing CE practices in the supply chain (SC). One of the objectives of this study is to determine current trends in SC based on the CE from 2013 to 2022. 101 articles are selected for in-depth analysis based on a bibliometric and network analysis approach. The review sheds light on the most important success factors of CE practices in SC across a variety of industries, as well as current and upcoming research trends. This review identifies research gaps and highlights additional theoretical approaches to the critical success factors of CE practices in the SC. The findings of this research will enable organisations to better understand the challenges and opportunities associated with CE practices and develop more efficient and sustainable SC strategies.

Exploring the alignment and misalignment in the transition to a circular economy within private companies and public organizations

The paper explores the alignment and misalignment of objectives within private companies and public organizations in their approach to the circular economy. While many studies have investigated the alignment within single actor types, this research reveals the dynamics of alignment when private companies and public organizations engage. Drawing upon qualitative research protocol, our study employs a circular economy financing initiative implemented in Italy as the empirical foundation for investigating these dynamics. The results highlight the positive repercussions when private companies and public organizations achieve perfect alignment, which triggers internal transformations within both entities. However, perfect alignment is seldom achieved. Our findings thus contribute to the literature by proposing actor misalignment as a potential barrier to the circular economy. This paper provides both theoretical and managerial insights into alignment dynamics within the context of the circular economy and offers a perspective on how these dynamics might evolve over time in multi-stakeholder circular economy initiatives.

The Urban-Industrial metabolism: contribution of waste recycling to the circular economy objectives within the construction sector

The construction and buildings sector is facing an urgent need to reduce GHG emissions and ensure efficient resource utilization while minimizing waste in order to comply with climate change policies and circular economy initiatives. Alkali-activated materials, as an alternative binder to CO2-intensive conventional cement, show potential in utilizing waste streams from urban environments in their production technology, thereby reducing CO2 emissions. This study examines two waste streams generated in Switzerland: incineration ashes from municipal solid waste treatment facilities and mineral wool waste from building stock renovation and demolition activities. Geospatial analysis is combined with LCA methods to assess optimal scenarios for waste recycling, utilizing a multi-objective optimization framework based on mixed integer linear programming. The objectives are to minimize the environmental impacts and costs associated with alternative supply chain networks, thereby identifying optimal locations for waste pre-treatment and concrete manufacturing. The proposed scenarios demonstrate reductions of 56% in global warming potential and 29% in costs when compared to the business-as-usual scenario of conventional cement concrete use and waste landfilling. Results show that recycling of urban waste streams in alternative concrete can reduce GHG emissions of industry and heavy transportation sectors by 0.46 mt. CO2 eq. by year 2030, equivalent to 23% and 4% of the Swiss carbon budget reduction targets for these sectors.