Circular Economy Goals Research Articles

An Analysis of the Círcular Economy in Europe through Comparative Research Employing the CRITIC-Based MAUT and COPRAS Methods

Purpose: The circular economy is an approach to sustainability that takes into account both the economic and environmental benefits of repurposing waste or underutilized inert assets into new, useable products or services. The research aims to present a comparative analysis of EU countries with multi-criteria decision-making methods using various indicators covering many topics, including emphasis on recycling, use of circular materials, material efficiency and collective management of waste. Methodology: The research aims to determine the weights through the application of the CRITIC method. It is gathered in 22 sub-indicators under three main categories, including sustainable resource management, social behaviour, and business operations, so as to assess effectiveness with regard to this notion while comparing nations. Additionally, every nation in the EU that has indicator data is assessed employing cluster analysis, a method of data mining, in addition to multi-criteria decision-making techniques like MAUT and COPRAS. Findings: Based on the assessments of nations, Denmark, Luxembourg, Finland, Austria, Sweden, the United Kingdom, and Germany exhibit a favourable and noteworthy distinction from other nations. Originality: This study offers the opportunity to make comparisons with a multi-criteria decision-making approach when it comes to environmental and circular economy goals.

Putting the ‘economy’ back in the circular economy

AbstractThis paper offers a business‐focused critique centring on the superordinate goal of circular economy (CE) strategy and advances an ideograph that can help economic planners and corporate leaders conceptualize CE strategies that meet the bifurcate goals of strengthening economic resilience while also attenuating resource footprints. The paper, based on critical discourse analysis (CDA) and supported by an extensive literature review, highlights the pervasive manner in which the CE is mischaracterized as a materials circulation (MC) strategy and demonstrates how an oft‐referenced ideograph—the Ellen MacArthur Foundation (EMF) Butterfly—graphically entrenches this characterization. The first contribution that this study makes centres on providing clarity on how CE principles can be integrated with corporate strategy to elevate competitive advantage through resource economic optimization (REO). The second contribution is the development of a reconceptualized ideograph—The Integrated Circular Economy (ICE) model—that better conveys how this strategic perspective on CE and be conflicted with economic networks to deliver better economic and environmental performance.

Circular Economy Goals, Large Capitalisation, and ESG Funds: An Investment Perspective

In the context of an obvious 32% growth, the relationship between the circular economy, risks and returns is becoming increasingly relevant. ESG indicators are increasingly pivotal in global investment decisions. The purpose of the study is to demonstrate that ESG-mandated companies are more likely to yield sustainable long-term performance, advocating for investors to consider ESG-based mutual fund schemes. The research evaluates the performance of the top 10 high-capitalization and ESG equity funds, comparing them to the Nifty-50 benchmark index using various performance metrics. An increasing trend in ESG-compliant investing is observed, contributing to the circular economy. It was concluded that even post-risk adjustment, ESG funds remain lucrative, offering sound long-term returns. Statistically significant returns are noted in both funds and index. The study recommends companies revise policies towards ESG compliance and investors kindness ESG funds. The novelty of the study is that it gives a new insight into the performance of two different categories of funds, how well circular economy strategies can contain investment risk and provide risk-adjusted returns.

Valorization of Agro-Industrial Orange Peel By-Products through Fermentation Strategies

The use of whole-cell biocatalysts in microbial cell factories is of great interest to produce added-value compounds. Through large-scale fermentative processes, which use secondary raw materials as substrates, it is possible to recycle and upgrade agro-industrial by-products. This review addresses the main fermentative processes and bioreactors currently used for the valorization of orange peel, a by-product of the Citrus processing industry. Among the main added-value products, bioethanol, organic acids, enzymes, single cell proteins (SCPs), dyes and aromatic compounds have been industrially produced using orange peel via solid state fermentation and submerged fermentation. This approach fits within the circular economy goals in terms of clean technology and renewable energy, valorization and recycling, upgrade of industrial by-products and sustainability.

The Impact of Globalization on Innovative Public Procurement: Challenges and Opportunities

Incorporating circular economy principles into forward-thinking public procurement strategies enhances sustainability through the promotion of resource efficiency, sustainable sourcing, and extended producer responsibility. This approach not only encourages innovation and collaboration among suppliers but also drives the development of solutions aligned with circular economy goals. The ultimate result is a more cost-effective and environmentally friendly outcome in procurement. This article seeks to investigate the intersection of circular economy principles within the framework of an innovative public procurement system. The study explores the influence of globalization on this innovative public procurement paradigm, addressing both the challenges and opportunities inherent in the process. The study conceptualizes Innovative Public Procurement (IPP) as a strategic approach where public entities acquire goods, services, works, and utilities, emphasizing an optimal balance between price and quality. The central goal is to generate innovative benefits for both entities and society, all while minimizing adverse environmental effects. Employing traditional research methods, including the monographic method, document analysis, and comparison, the study illustrates how public procurement practices can be opened to innovators, including start-ups and innovative SMEs. The findings shed light on the challenges faced by these entities in navigating the procurement landscape, while emphasizing the potential opportunities arising from the synergy between innovative procurement practices and the circular economy. By adopting a holistic perspective that considers the full lifecycle costs and environmental impacts of goods and services, procurement decisions can prioritize options offering superior long-term value. This contributes to the broader transition towards a circular economy, effectively minimizing adverse effects on the environment...

Optimizing sustainable concrete compressive strength prediction: A new particle swarm optimization‐based metaheuristic approach to neural network modeling for circular economy and disaster resilience

AbstractThis study aims to predict the final‐age compressive strengths of sustainable concrete series produced using different aggregate types with high accuracy using an artificial intelligence model and to reduce environmental degradation and conserve rapidly decreasing natural resources within the scope of sustainable development and circular economy goals. For this purpose, 45 different sustainable concrete series containing all‐natural, recycled, natural, and recycled concrete aggregates were produced and subjected to compressive strength tests at 7 and 28 days. In addition, this study also considers whether deep neural network models, which have gained popularity in recent years but have high time and resource costs, or shallow models are more suitable for determining the compressive strength values with high accuracy. For this purpose, a method is proposed that can automatically generate the optimal neural network model using a metaheuristic approach that eliminates the human factor. For this purpose, the proposed method was extensively compared with different classical machine learning algorithms. The proposed method predicted the 7 and 28‐day compressive strength with a coefficient of determination of 0.999 and presented better compressive strength predictions than all other algorithms. Considering the number of buildings to be constructed after earthquakes, the widespread use of concrete, and the importance of compressive strength, the proposed method will likely provide significant gains within sustainable development, circular economy, and disaster risk reduction.

Does the Rubber Meet the Road? Assessing the Potential of Devulcanization Technologies for the Innovation of Tire Rubber Recycling

Innovation is crucial to meet the circular economy goals for tire recycling. Devulcanization, an innovative recycling method of reprocessing tire rubber, offers a pathway towards achieving circular economy objectives. While previous research on devulcanization has primarily focused on technical aspects, this study shifts the focus towards identifying opportunities and barriers for innovation through devulcanization. This research utilizes the Technological Innovation System framework as a basis to analyze the dynamics of innovation within value chains and innovation networks. Across Europe, 36 organizations were identified that develop and utilize devulcanization to transform rubber from end-of-life tires into a valuable resource for new rubber products. In this study, a semi-structured in-depth interview approach was applied to interview 12 organizations that have developed or utilize technologies for the devulcanization of tire rubber. It was found that the development of various devulcanization approaches for diverse types of products has created opportunities for upscaling. To capitalize on these opportunities, organizations need to collaborate throughout the entire value chain of tire production and recycling. Achieving this collaboration requires interventions across the industry.

Implementation of Additive Manufacturing in the Healthcare Supply Chain for Circular Economy Goals: Paradoxical Tensions and Solutions from an Industry 5.0 Perspective

AbstractThis study addresses the paradoxical tensions that arise during additive manufacturing (AM) implementation for circular economy goals in the healthcare sector. Using the lens of paradox theory, this study identifies four competing priorities that stakeholders may encounter while adopting AM. Focus group discussions among 12 industry experts from the healthcare supply chain were conducted to verify the paradoxes. Semi-structured interviews were then conducted with 10 industry experts to derive the solutions to manage these tensions from an Industry 5.0 perspective to achieve the full benefits of AM. This study expands paradox theory into the AM literature and provides a novel ‘both/and’ perspective (i.e. a pluralistic rather than a dualistic perspective) to look at emerging tensions encountered while implementing AM in the healthcare sector. This perspective will help decision-makers realise that these tensions can be managed over time to turn them into creative, rather than destructive, forces.

Leveraging intellectual capital for building a supply chain circular economy system: A knowledge-based view

Organizations are inevitably pursuing circular economy goals through a supply chain approach. This paper examines the impact of intellectual capital on supply chain circular economy (SCCE) systems made up of a closed-loop supply chain (CLSC) and a reverse omnichannel. By employing the knowledge-based view, this paper constructed the relationship between intellectual capital and SCCE systems. We tested the proposed hypotheses by employing structural equation modeling on a dataset collected from 193 Chinese manufacturing firms. Finally, we used a bootstrap method and tested the indirect effect of intellectual capital components on SCCE systems. We found that intellectual capital both directly and indirectly contributed to SCCE systems. Human capital and structural capital, in particular, were positively associated with CLSC, whereas social capital was strongly related to reverse omnichannel. However, human capital and structural capital had no significant relationship with reverse omnichannel, and social capital had no significant impact on CLSC. We also found that structural capital mediated the human capital-CLSC association, and social capital played a mediating role between human capital and reverse omnichannel. Drawing on the knowledge-based view, our study offers insights into the intellectual capital literature, circular economy literature, and supply chain management literature. The findings add to our existing understanding of how existing knowledge of the organization can be leveraged for better operations by CLSC and improved services by reverse omnichannel.

Enabling circular economy practices in regional contexts: Insights from the UK Southwest

While much research has focused on embedding circular economy (CE) practices in urban contexts, there is growing interest in the opportunities and challenges of rural settings. Adopting a regional lens can account for local knowledge, collective practices and community memory, yet CE conceptualisations often lack both a place-based dimension and a consideration of regional stakeholders. The aim of this paper is to explore the role of various stakeholders, in driving the adoption and implementation of CE practices at a regional level. We do this through engagement with 31 participants from business, governance and community groups in a peripheral region situated in the Southwest of the UK. Using stakeholder theory and thematic analysis of interviews, participant observation and workshop scripts, we identify ‘influencers’ as a key stakeholder group leading the implementation of regional CE goals and practices. Furthermore, we highlight key barriers and enabling factors which underpin interactions among different stakeholder groups and discuss their implications for regional CE transition.

Revolutionizing Urban Waste Management in San Francisco: The Role of Technology-Driven Solutions in Advancing Circular Economy Practices

This study analyses the impact of technology-driven solutions on urban waste management within the U.S. circular economy, focusing on San Francisco as a case study. San Francisco's waste management system, characterized by its innovative use of technology, robust policy frameworks, and active community engagement, serves as a model for understanding the implementation and challenges of sustainable urban practices. The research employs a case study methodology, relying on a comprehensive review of secondary data sources, including official reports, academic literature, and statistical data. The findings reveal that while technological advancements, such as advanced sorting systems, composting technologies, and waste-to-energy initiatives, significantly enhance waste management efficiency, they also bring challenges in terms of financial and infrastructural constraints. The study underscores the importance of supportive policy frameworks and community engagement in facilitating the success of these initiatives. Despite its successes, San Francisco’s approach highlights key challenges, including maintaining technological advancement and ensuring community participation. The study concludes that the integration of technology in waste management, underpinned by strong policies and community engagement, is crucial in advancing circular economy goals. The insights from San Francisco’s experience provide valuable lessons for other cities aiming to implement similar sustainable waste management practices.

PHOENIX: Towards a circular economy of plasmix waste—A systemic design approach

Plastic recycling is a critical aspect of achieving a circular economy, aiming to reduce fossil fuel dependency, greenhouse gas emissions, and biodiversity impacts from uncontrolled disposal routes. The study outlines the evolving landscape of plastic recycling in the European Union (EU), addresses challenges, and emphasizes the need for innovative approaches to achieve circular economy goals. This paper delves into the innovative approaches and strategies employed by the PHOENIX project, a multidisciplinary project funded by the Cariplo Foundation, which focuses on plasmix – a complex mixture of plastics often excluded from recycling due to its heterogeneous composition. The authors utilize a systemic design approach, integrating survey results, interviews, literature reviews, and case studies to provide a comprehensive understanding of plasmix and propose novel solutions. Key findings include the application of design from recycling, systemic design strategies, and the utilization of plasmix in new product developments. It presents survey insights and stakeholder perspectives, and introduces systemic strategies applied in the project. The study concludes with valuable considerations for future research and underscores the significance of such initiatives in reshaping the plastic recycling paradigm.

Harmony with nature: Disentanglement the influence of ecological perception and adaptation on sustainable development and circular economy goals in country

From the perspective of ecosystem attributes, this research was conducted to explore the impact of people's adaptation and response to their perception of environmental risks on their preference for sustainable development strategies and the realization of a circular economy based on Social Judgment Theory and the Value-Belief-Norm (VBN) theory. To achieve the goal, three substudies were conducted using questionnaire surveys—the first substudy aimed to examine the influence of ecological attributes on environmental risk perception (ERP). The second substudy attempted to understand the intricate connection between ERP and justice, while the third study explored the relationship between justice and SDS (sustainable development strategies) and CEG (realization of a circular economy). The results indicate the following: (1) The first substudy reveals that ecological attributes impact environmental risk perception (ERP), with different environmental values exerting distinct influences. (2) The second substudy suggests that ERP facilitates the realization of social, environmental, and ecological justice, but people's preference for a specific economic growth strategy will affect their tendency to realize justice. (3) The third substudy shows that sustainability strategies (i.e., sustainable production, consumption, and use) mediate the relationship between justice and circular economy goals (CEG). Among the three strategies, sustainable use plays the most significant mediating role. The research outcomes underscore the importance of prioritizing sustainable use in future research in theory and practice.

Waste to energy, indispensable cornerstone for circular economy: A mini-review.

This mini-review aims at proving that waste-to-energy (WtE) is an essential cornerstone for circular economy (CE). Based on literature, the history of thermal waste treatment over the last 150 years is investigated, from open burning to WtE with resource recovery and final sink function. The results show that in the past incineration solved the issues it was designed for but often created new and sometimes even worse problems: The introduction of incineration in the 19th century improved urban sanitation, decreased waste volume and prolonged operational life of landfills. But it also polluted the environment, triggering an unprecedented scientific and engineering effort of all stakeholders. Today, WtE is one of the best investigated and optimized technologies in waste management. It enables the recovery of energy as heat and electric power and facilitates the 'cleaning' of cycles by the destruction of hazardous organic substances. Recent developments in resource recovery from WtE residues allow to recycle metals and, in the case of sewage sludge, even phosphorus by thermal recycling. Combined with carbon capture and storage technology, WtE stands for a quantifiable contribution to greenhouse gas reduction. Today, WtE is indispensable to reach the goals of CE, namely recycling of energy and materials, supplying safe final sinks for persistent organic substances and minimizing the need for sinks for hazardous inorganic substances.

Four-decades evolutionary development of municipal solid waste management in China: Implications for sustainable waste management and circular economy.

This study collected data on waste generation and management in China between 1979 and 2020 from government statistics and literature and reviewed the development of municipal solid waste (MSW) management in China. The extended stochastic impact by regression on population, affluence and technology (STIRPAT) model was employed to identify the driving forces of MSW generation, and the cointegration analysis showed that economy (0.35, t = -3.47), industrial structure (3.34, t = -20.77) and urbanization (-1.5, t = 5.678) were the significant socioeconomic driving forces in the long run. By employing the framework of evolutionary economics, this study then investigated the internal rules of long-term interaction between socioeconomic factors and MSW management. The results indicate that, in the long run, MSW management development can be viewed as an evolutionary process that includes a continuous adaptation to external socioeconomic factors and the co-evolution of internal institutions and technologies. Adaptation and diversity of institutions and technologies play an important role in achieving sustainable waste management and circular economy (CE). This study offers a novel evolutionary perspective for explaining dynamic changes of MSW management in China, as well as recommendations for emerging economies to achieve sustainable waste management and CE goals.

Enabling Net-Zero GHG Emissions in the UK Metals and Transport Industries through a Circular Supply Chain Framework

The UK metals industry is indispensable in achieving the country’s net-zero greenhouse gas (GHG) emissions target by 2050, especially considering the heavy reliance of the transport sector on metals. This paper proposes strategies based on recycling and refining locally sourced scrap metals to build a robust circular supply chain. Findings revealed that 16% of global crude steel is used in transport and this accounts for 8% of the world’s GHG emissions. Domestically, iron and steel account for 14% of the UK industrial emissions, with over 8 million metric tons of scrap metals exported annually. Insights from stakeholders revealed export dependency and infrastructure gaps impeding circularity. Collaborative efforts between industry, government, and recyclers are vital. Investing in electric arc furnaces and storage can enable the processing of domestic metal scrap for high-quality yield. A closed-loop flow of battery-critical metals will also support sustainable manufacturing of electric vehicles. Ultimately, this paper advocates systemic efforts across policy, technology, infrastructure, and partnerships to realise a sustainable supply chain in the metals industry aligned with the decarbonisation and circular economy goals.

A Holistic Self-Assessment Tool for Circular Economy Transitions in Cities and Regions

In the European context, cities and regions play a key role in boosting circularity and achieve the European Green Deal action plan mbition to ‘boost the efficient use of resources by moving to a clean, circular economy’. To this end, cities and regions will be instrumental in promoting circularity through engagement with key actors and integration of circular economy (CE) goals within their policies and spatial plans. To support this effort, it is essential to develop appropriate metrics and tools for evaluating the progress and transition towards a circular economy. Although numerous new assessment methodologies have been suggested (Corona et al., 2019), they generally focus on quantitatively assessing how circular a project, system, or business is, or on evaluating the extent to which circular strategies align with the principles of a circular economy. Current metrics rarely extend beyond material sustainability assessments, which means they often do not capture the complexity of the CE transition and lack a comprehensive, integrated perspective. In particular, what they omit are the spatial (Williams, 2020), the governance (Korhonen et al., 2018) and the social dimensions (Pitkänen et al., 2020). In this paper, we propose a holistic transition assessment tool developed and tested across several metropolitan regions, including Amsterdam, Naples, Łódź, Hamburg and Pécs, being at different stages of the circular economy transition. The final version of the tool was applied in two cases, the Amsterdam Metropolitan Area and the city of Tomaszów Mazowiecki. The tool focuses on five dimensions: (1) governance structures, (2) awareness, comprehensiveness of the sustainability assessment, (3) tools for measuring material stocks and flows as well as (4) for co-creation of solutions and strategies with stakeholders, and (5) circular built environment. The results of applying the tool in a series of workshops with regional CE stakeholders allow for exploring the following questions: What is the state of the transition towards CE in European urban regions from a holistic perspective? What hinders these transitions? And how to identify means to overcome those barriers? The assessment tool is of interest for regional and urban policy-makers, planners and stakeholders engaged in development of CE strategies and policies. What is more, the results presented in the paper allow for comparative insights into the state of transition towards CE and for drawing lessons on what it takes to nudge the development of regions and cities towards circularity.

Process development and techno-economic analysis for mechanochemical recycling of poly(ethylene terephthalate)

Chemical recycling of consumer plastics has garnered great attention recently towards achieving circular economy goals. Particularly in the case of PET waste, mechanochemical depolymerization in ball mill reactors has been identified as a very promising technology due to the high conversion rates achieved under mild conditions. While the absence of solvents in the reaction mixture reduces significant separation costs, mechanochemical depolymerization still presents challenges with respect to the efficient separation and purification of monomers. Thus, meticulous experiments, process modeling, and simulations are essential for demonstrating the separation and purification of monomers. In this study, we present the lab-scale separation process flow for the recovery of terephthalic acid (TPA) and ethylene glycol (EG) from mechanochemically depolymerized polyethylene terephthalate (PET). We additionally examine the use recycling of ideal PET powder and commercial samples (e.g., PET fibers, bottles, and food containers) as feedstocks. The process parameters are optimized to achieve 97 %+ of monomer recovery with 99 %+ purity. The complete recovery of EG, and recycling of process water enables a ‘zero-liquid discharge’ process design. Subsequently, we conduct a techno-economic analysis (TEA) to evaluate the economic potential of the proposed sequence, which resulted in a positive net present value (NPV) for the different scenarios and a minimum selling price (MSP) of $0.99/kg. Finally, we compare the economic potential of mechanochemical recycling of PET to fossil-based production and other recycling methodologies based on economic metrics.

Ureolytic bacteria-assisted recycling of waste concrete fines

This study investigates the potential of microbially-induced calcite precipitation (MICP) in converting waste concrete fines (WCF), an underutilized byproduct generated during the crushing of old concrete, into construction material. WCF samples treated with Sporosarcina pasteurii DSM 33 for periods ranging from 14 to 90 days exhibited up to an 11% increase in CaCO3 content, compared to a control group treated with a saline solution. The formation of CaCO3 crystals also resulted in a 15% reduction in porosity and, most importantly, enhanced the integrity of the WCF conglomerates, reaching 20% of the stiffness of autoclaved aerated concrete. These results suggest that MICP could be used for the valorization of WCF, aligning with sustainability and circular economy goals.

Environmental sustainability assessment of different end-of-life scenarios for the pulper rejects produced in the paper recycling process

Resource recovery from wastes through recycling processes promotes near-zero-waste residue business models and supports the circular economy's goals by facilitating the closure of loops in industrial systems and reducing energy and resource consumption as well as pollutant emissions. However, the approach is sustainable only when the waste can be valorized, and the environmental impact of the recycling is lower with respect to other end-of-life (EOL) scenarios. Due to the diversity and complexity of wastes streams, these aspects need to be evaluated on a case-by-case basis.This study focuses on a mechanical recycling process for pulper rejects, a mixed waste stream generated during recycled paper production, with two aims: (1) to define a feasible mechanical recycling process and (2) to evaluate its environmental performance through life cycle assessment (LCA) compared to the most common EOL treatments, such as incineration with energy recovery and landfilling. ReCiPe 2016 H method was used to estimate the environmental impacts of all scenarios, adopting both midpoint and endpoint approaches, on a functional unit (FU) defined as 1000 kg of pulper rejects. The LCA results indicate that the pulper rejects recycling is always preferable to landfilling across all impact categories considered. On the contrary, in comparison to incineration, the best environmental option depends on the specific impact category considered. In particular, recycling is the best EOL alternative in terms of impacts on global warming, with an impact 33 % lower, but it is not the most sustainable one in terms of fossil resource consumption, mainly due to the amount of energy required during all steps of the recycling process, while allowing the recovery of materials that would otherwise be lost. Currently, it is not possible to identify an overall ‘winner’ between incineration with energy recovery and recycling for the pulper rejects because the most environmentally sound alternative varies depending on the priority given to different environmental issues. Therefore, further improvements of the pulper rejects recycling pathway performances are required to make the process even more efficient and competitive.