Circular Economy最新文献

{"title":"Biotechnological approaches: Degradation and valorization of waste plastic to promote the circular economy","authors":"Sridevi Veluru ,&nbsp;Ramakrishna Seeram","doi":"10.1016/j.cec.2024.100077","DOIUrl":"10.1016/j.cec.2024.100077","url":null,"abstract":"<div><p>The practical application of plastics is as indispensable as it is problematic regarding disposal. Plastics present significant opportunities in the context of circular usage and recycling. A circular economy dictates the utilization of every side stream to minimize waste. Current waste management techniques are insufficient in reducing plastic waste entering landfills, wastewater treatment systems, and the environment. Under these circumstances, plastic biodegradation has emerged as a viable and environmentally responsible approach to plastic pollution. Methods are needed for the natural degradation of plastics using microbes that can utilize plastics as their sole carbon source. Studies to enhance the catalytic activity of plastic-degrading enzymes through protein engineering approaches are a relatively new field of research. Enzymatic degradation for product creation represents a purely biological plastic recycling method in a sustainable economy. This review builds insights derived from previous studies and provides a brief overview of plastic degradation using enzymes, improvements in plastic-degrading enzyme efficiency, and stabilization via various protein engineering strategies. In addition, recent advances in plastic waste valorization technology based on systems metabolic engineering and future directions are discussed.</p></div>","PeriodicalId":100245,"journal":{"name":"Circular Economy","volume":"3 1","pages":"Article 100077"},"PeriodicalIF":0.0,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2773167724000050/pdfft?md5=4b610f8275feb9110300a0e663da825b&pid=1-s2.0-S2773167724000050-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140086533","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Extended producer responsibility to reconstruct the circular value chain","authors":"Xin Tong,&nbsp;Tao Wang,&nbsp;Jinling Li,&nbsp;Xuejun Wang","doi":"10.1016/j.cec.2024.100076","DOIUrl":"10.1016/j.cec.2024.100076","url":null,"abstract":"<div><p>This research explores the role of extended producer responsibility (EPR) as an enabler of circular value chain in the Chinese context. The driven forces and key stakeholders were identified to extend producer responsibility in developing the national-circular-economy strategies. An evaluation system was established to link the eco-design strategy of the producer with the downstream-recycling performance of products. The eco-design information was retrieved from the self-disclosure information in the sustainable development report of producers. The downstream-waste-flow information comes from multiple platforms of reuse and recycling companies. The aim of reforming the EPR system is to establish an open forum for competition and cooperation among different stakeholders to achieve a continuously-improving target of circularity and life cycle environmental performance of the products. With the evaluation results, the producers are encouraged to fully explore all opportunities in the circular value chain instead of focusing only on the final disposal or disassembly of waste. The conclusion suggests that EPR policies should break the restrictions on eco-design and innovation in business models by creating and capturing values of circularity along with the world's collective climate change mitigation efforts.</p></div>","PeriodicalId":100245,"journal":{"name":"Circular Economy","volume":"3 1","pages":"Article 100076"},"PeriodicalIF":0.0,"publicationDate":"2024-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2773167724000049/pdfft?md5=a2f6fd1bfeefb30d997276d40cf959d9&pid=1-s2.0-S2773167724000049-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139884128","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"PHOENIX: Towards a circular economy of plasmix waste—A systemic design approach","authors":"Eleonora Fiore ,&nbsp;Paolo Tamborrini","doi":"10.1016/j.cec.2024.100075","DOIUrl":"https://doi.org/10.1016/j.cec.2024.100075","url":null,"abstract":"<div><p>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.</p></div>","PeriodicalId":100245,"journal":{"name":"Circular Economy","volume":"3 1","pages":"Article 100075"},"PeriodicalIF":0.0,"publicationDate":"2024-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2773167724000037/pdfft?md5=2daa63567cb43d8d972bf1c24aa15378&pid=1-s2.0-S2773167724000037-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139936922","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Extended producer responsibility to reconstruct the circular value chain","authors":"Xin Tong, Tao Wang, Jinling Li, Xuejun Wang","doi":"10.1016/j.cec.2024.100076","DOIUrl":"https://doi.org/10.1016/j.cec.2024.100076","url":null,"abstract":"","PeriodicalId":100245,"journal":{"name":"Circular Economy","volume":"375 5","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139824368","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Extended producer responsibility to enable an inclusive circular economy","authors":"Xin Tong, Jingwei Wang","doi":"10.1016/j.cec.2024.100074","DOIUrl":"https://doi.org/10.1016/j.cec.2024.100074","url":null,"abstract":"","PeriodicalId":100245,"journal":{"name":"Circular Economy","volume":"51 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139882931","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Preparing polyethylene composites using nonmetallic fractions derived from waste printed circuit boards and shellfish waste: Toward synergistic waste utilization and circular economy","authors":"Jiayao Tong ,&nbsp;Shaoqi Yu ,&nbsp;Zhitong Yao ,&nbsp;Jingjing Jiang ,&nbsp;Hongwei Lu ,&nbsp;Ying-Guo Zhou ,&nbsp;Hongli Yang ,&nbsp;Zhengshun Wen","doi":"10.1016/j.cec.2024.100073","DOIUrl":"https://doi.org/10.1016/j.cec.2024.100073","url":null,"abstract":"<div><p>The recycling of waste printed circuit boards (WPCBs) generates nonmetallic fractions (NMFs); due to the complex components of NMFs and the limited nature of economic benefits of treating NMFs, treatment of NMFs is challenging. In this study, two types of NMFs—dry-NMFs (D-NMFs) and wet-NMFs (W-NMFs)—derived from the dry and wet separation processes of WPCBs, respectively, were investigated. These NMFs were used as fillers to reinforce the polyethylene (PE) matrix, and their effects on the composite properties were examined. Thermal property studies revealed that incorporating both types of NMFs improved the thermal stability of the prepared composite samples. When neat PE was filled with 15 wt% of D-NMFs and W-NMFs, the final decomposition temperature (<em>T</em>_f) increased from 475 to 482 and 487 °C, respectively. Mechanical property studies revealed that the addition of NMFs to the composite sample, particularly that of W-NMFs, enhanced the stiffness of the prepared samples, although at the expense of some reduction in their toughness values. The tensile strength, tensile modulus, flexural strength, and flexural modulus values increased from 9.41, 121.80, 5.89, and 99.15 MPa for neat PE to 11.15, 521.82, 17.94, and 597.29 MPa, respectively, for composites containing 25 wt% of W-NMFs. Furthermore, the introduction of shellfish wastes in the NMF/PE blend, especially that of clam shell, further enhanced the overall properties of the composite. After adding 8 wt% of clam shell with 15 wt% W-NMFs, the <em>T</em>_f increased from 487 to 498 °C. The tensile strength, tensile modulus, flexural strength, and flexural modulus values increased from 11.37, 355.13, 16.06, and 443.31 MPa for neat PE to 12.26, 466.73, 18.71, and 568.46 MPa, respectively, for the composite prepared with clam shell. Thus, this study contributes to the WPCB recycling literature and promotes circular economy development.</p></div>","PeriodicalId":100245,"journal":{"name":"Circular Economy","volume":"3 1","pages":"Article 100073"},"PeriodicalIF":0.0,"publicationDate":"2024-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2773167724000013/pdfft?md5=e5bf08dbe86ada37026531f210201009&pid=1-s2.0-S2773167724000013-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139936923","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Systems and Ecosystems in the Circular Economy: What’s the Difference?","authors":"Wisdom Kanda","doi":"10.55845/rmdn3752","DOIUrl":"https://doi.org/10.55845/rmdn3752","url":null,"abstract":"‘Systems’ and ‘ecosystems’ are buzz concepts in the circular economy literature. However, the differences between these concepts remain ambiguous. Systems and ecosystems are often used interchangeably and at times confusingly. While conceptual ambiguity offers possibilities for broad interpretations and engagement, it can undermine the relevance of these concepts as analytical lenses to disrupt the linear economy. In this perspective article, I examine whether systems and ecosystems are distinct concepts and how they complement each other. To do so, I analysed these concepts and applied them to a case of biomethane for transportation using scientific literature. Systems and ecosystems are not mutually exclusive; rather, they offer nuanced perspectives to describe, analyse, and facilitate complex interactions among entities and their external environment. They signify the complexity, interdependency, and co-evolutionary nature of the circular economy. Ecosystems are a subcategory of systems. Differences between the concepts of systems and ecosystems partially arise from their origins, evolution, and the research communities using them. The article shows how systems and ecosystems perspectives can enrich each other and calls for better integration between the two concepts in the circular economy discourse.","PeriodicalId":100245,"journal":{"name":"Circular Economy","volume":" 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139393617","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Co-processing paths of agricultural and rural solid wastes for a circular economy based on the construction concept of “zero-waste city” in China","authors":"Hongbin Cong ,&nbsp;Haibo Meng ,&nbsp;Mingsong Chen ,&nbsp;Wei Song ,&nbsp;Haohan Xing","doi":"10.1016/j.cec.2023.100065","DOIUrl":"https://doi.org/10.1016/j.cec.2023.100065","url":null,"abstract":"<div><p>The treatment and utilisation of agricultural and rural solid wastes are important initiatives to advance high-quality agricultural development and improve rural living environment in a concerted manner. We identified the general background and need of agricultural andrural solid wastes in China, and elucidated the main sources and classified the agricultural and rural solid wastes; we grouped the wastes according to their source, value, components, and form, and described the basic characteristics of agricultural and rural solid wastes, namely, diversity, spatio-temporal fluctuations, and consistency of collection. Based on this, the technical pathways of agricultural and rural solid waste co-processing were systematically summarised for a circular economy based on the construction concept of ‘zero-waste city’ in China, including conversion to fertilisers and energy, value enhancement, and volume reduction. Three main models were developed, namely, the mixed fermentation of agricultural and rural solid wastes for fertiliser production, mixed pyrolysis/gasification/incineration for energy production, and urban-rural integrated waste treatment. Subsequently, we systematically analysed the main framework, fundamental characteristics, and applicable scenarios of the three models. We established the foundations and strategies for the co-processing and efficient utilisation of agricultural and rural solid wastes.</p></div>","PeriodicalId":100245,"journal":{"name":"Circular Economy","volume":"2 4","pages":"Article 100065"},"PeriodicalIF":0.0,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2773167723000420/pdfft?md5=f435bcf571b607f97d1725a4e7b165a0&pid=1-s2.0-S2773167723000420-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138483991","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Recent advances of research in coal and biomass co-firing for electricity and heat generation","authors":"Li Liu ,&nbsp;Muhammad Zaki Memon ,&nbsp;Yuanbo Xie ,&nbsp;Shitie Gao ,&nbsp;You Guo ,&nbsp;Jingliang Dong ,&nbsp;Yuan Gao ,&nbsp;Aimin Li ,&nbsp;Guozhao Ji","doi":"10.1016/j.cec.2023.100063","DOIUrl":"https://doi.org/10.1016/j.cec.2023.100063","url":null,"abstract":"<div><p>Coal-fired power generation resulted in a shortage of conventional fossil fuels and an increase in greenhouse gas emissions. The co-firing of coal and biomass waste in coal-fired boilers was a promising strategy to supplement the energy source and reduce greenhouse gases. However, the co-firing mechanism and potential problems were not well understood. Therefore, the differences between coal and biomass in properties such as proximate and ultimate composition, components in ash and the calorific value were first discussed. Next, compared with the combustion of coal alone, this review analyzed the discrepancies and corresponding issues of co-firing in combustion behaviors and products such as ash and gaseous pollutants. Finally, this review outlined how operational conditions could affect the co-firing performance.</p></div>","PeriodicalId":100245,"journal":{"name":"Circular Economy","volume":"2 4","pages":"Article 100063"},"PeriodicalIF":0.0,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2773167723000407/pdfft?md5=f831fc20f57da638b1b34ac70744e0e8&pid=1-s2.0-S2773167723000407-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138501959","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A recycling technology selection framework for evaluating the effectiveness of plastic recycling technologies for circular economy advancement","authors":"Idowu O. Kunlere,&nbsp;Kalim U. Shah","doi":"10.1016/j.cec.2023.100066","DOIUrl":"https://doi.org/10.1016/j.cec.2023.100066","url":null,"abstract":"<div><p>Despite progress in plastic waste recycling technologies, global plastic waste recycling rates remain disappointing. This issue not only suggests an underutilization of existing recycling technologies but also hinders resource utilization, the circular economy, and sustainable manufacturing. Several studies have proposed to address this issue, such as by evaluating the efficiency of recycling technologies based on the volume of recycled waste. However, such single-indicator methods often overlook other critical factors and, thus, may not provide holistic assessments. Additionally, existing methods for evaluating or comparing different recycling technologies are often complex and time-consuming. Meanwhile, several other studies have proposed hundreds of indicators for assessing the effectiveness and suitability of recycling technologies, which often complicates the selection process. Consequently, recyclers and other stakeholders often struggle to select effective and suitable recycling technologies for different plastic waste types and under specific conditions. To address these challenges, we propose the recycling technology selection framework (RTSF), a simple tool that enables easy visualization of relevant recycling indicators under five key pillars: economic, technical, environmental, social, and policy. By allowing recyclers and stakeholders to quickly identify, select, and visualize factors of interest from a large pool, the RTSF enables qualitative comparison and enhances the evaluation of the effectiveness and suitability of multiple plastic recycling technologies. Lastly, the RTSF can serve as a preliminary tool and be used in conjunction with other approaches to enhance the effectiveness of plastic recycling technologies.</p></div>","PeriodicalId":100245,"journal":{"name":"Circular Economy","volume":"2 4","pages":"Article 100066"},"PeriodicalIF":0.0,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2773167723000432/pdfft?md5=d47b7580938de439e2fb470d66b243b9&pid=1-s2.0-S2773167723000432-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138471822","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}