Environmental Sustainability Analysis of Case Studies of Agriculture Residue Exploitation

Barriers to implementing circular citrus supply chains: A systematic literature review

Citrus is one of the world's most popular and widely cultivated fruits. The processing of citrus fruits for juice extraction generates solid and liquid biowaste, a valuable bio-resource that can be utilized in various sectors, including food and non-food industries. Incorporating Circular Economy (CE) principles into the citrus supply chain offers numerous opportunities but also presents certain barriers. The existing literature lacks a comprehensive study that explicitly explores the obstacles hindering the implementation of citrus waste valorization. Therefore, this study adopts a systematic literature review approach to answer three research questions related to defining the valorization processes and pathways of citrus processing waste to achieve net-zero waste and to explore, classify, and analyze the barriers to the implementation of Circular Citrus Supply Chains (CCSC). One hundred twenty-eight distinct barriers have been identified and classified into seven categories: economic, regulatory, technological, informational, market-related, managerial, and logistical. The most significant categories for CCSC were technological, economic, and informational barriers. This study provides practitioners and academics with a comprehensive understanding of the valorization opportunities and the various challenges faced during the adoption of circular models within the citrus processing supply chain. The findings thus provide a platform for the development of more competitive and sustainable strategies for CCSC. Additionally, future work was proposed regarding stakeholder engagement, barriers investigation, valorization processes' technical and economic feasibility, the interrelationship between barriers, and the effect of integrating emerging technologies to advance the CCSC field further.

The complexities of decision-making in food waste valorization: A critical review

The efficient utilization of food waste (FW) resources through Food Waste Valorization (FWV) has received increasing attention in recent years. Various decision-making studies have been undertaken to facilitate FWV implementation, such as the studies on decision-making framework and FWV technology assessment. Food waste hierarchy is a widely discussed framework in FW management, but it was found too simplified and does not always contribute positively to environmental sustainability. Moreover, decision-making studies in FWV often focus on specific aspects of the food system and employ distinctive decision-making approaches, making it difficult to compare the results from different studies. Therefore, our literature review is conducted to provide a comprehensive understanding of FWV decision-making. This study identifies what decisions are needed, and three levels of decisions are revealed: system-level, FW stream-level, and FWV option-level. The assessment approaches and criteria used to support decision-making in FWV are also collected and analyzed. Building upon these findings, an hourglass model is synthesized to provide a holistic illustration of decision-making in FWV. This study untangles the complexities of FWV decision-making and sheds light on the limitations of current studies. We anticipate this study will make more people realize that FWV is a multidisciplinary issue and requires the collective participation of researchers, practitioners, policymakers, and consumers. Such collective engagement is essential to effectively address practical challenges and propel the transition of the current food system toward a more resource-efficient paradigm.

Life Cycle Assessment of Rare Earth Elements-Free Permanent Magnet Alternatives: Sintered Ferrite and Mn-Al-C

Permanent magnets are fundamental constituents in key sectors such as energy and transport, but also robotics, automatization, medicine, etc. High-performance magnets are based on rare earth elements (RE), included in the European list of critical raw materials list. The volatility of their market increased the research over the past decade to develop RE-free magnets to fill the large performance/cost gap existing between ferrites and RE-based magnets. The improvement of hard ferrites and Mn-Al-C permanent magnets plays into this important technological role in the near future. The possible substitution advantage was widely discussed in the literature considering both magnetic properties and economic aspects. To evaluate further sustainability aspects, the present paper gives a life cycle assessment quantifying the environmental gain resulting from the production of RE-free magnets based on traditional hexaferrite and Mn-Al-C. The analysis quantified an advantage of both magnets that overcomes the 95% in all the considered impact categories (such as climate change, ozone depletion, human toxicity) compared to RE-based technologies. The benefit also includes the health and safety of working time aspects, proving possible reduction of worker risks by 3-12 times. The results represent the fundamentals for the development of green magnets that are able to significantly contribute to an effective sustainable transition.

Improvement of Interfacial Adhesion and Thermomechanical Properties of PLA Based Composites with Wheat/Rice Bran

The present work aims to enhance the use of agricultural byproducts for the production of bio-composites by melt extrusion. It is well known that in the production of such bio-composites, the weak point is the filler-matrix interface, for this reason the adhesion between a polylactic acid (PLA)/poly(butylene succinate)(PBSA) blend and rice and wheat bran platelets was enhanced by a treatment method applied on the fillers using a suitable beeswax. Moreover, the coupling action of beeswax and inorganic fillers (such as talc and calcium carbonate) were investigated to improve the thermo-mechanical properties of the final composites. Through rheological (MFI), morphological (SEM), thermal (TGA, DSC), mechanical (Tensile, Impact), thermomechanical (HDT) characterizations and the application of analytical models, the optimum among the tested formulations was then selected.

The powerful Solanaceae: Food and nutraceutical applications in a sustainable world

The Solanaceae family is considered one of the most important families among plant species because, on one hand encompasses many staple food crops of the human diet while, on the other hand, it includes species rich in powerful secondary metabolites that could be valorized in medicine or drug formulation as well as nutraceuticals and food supplements. The main genera are Solanum, Capsicum, Physalis, and Lycium which comprise several important cultivated crops (e.g., tomato, pepper, eggplant, tomatillo, and goji berry), as well as genera notable for species with several pharmaceutical properties (e.g., Datura, Nicotiana, Atropa, Mandragora, etc.). This chapter discusses the nutritional value of the most important Solanaceae species commonly used for their edible fruit, as well as those used in the development of functional foods, food supplements, and nutraceuticals due to their bioactive constituents. The toxic and poisonous effects are also discussed aiming to highlight possible detrimental consequences due to irrational use. Finally, considering the high amount of waste and by-products generated through the value chain of the main crops, the sustainable management practices implemented so far are presented with the aim to increase the added-value of these crops.

Romania’s Perspectives on the Transition to the Circular Economy in an EU Context

The main objective of the paper is to highlight Romania’s perspectives on the transition process towards the circular economy, in respect with the tendencies registered at the level of the European Union. To this end, our methodology involved the selection of four indicators, each one being viewed as representative for one area of interest specified in the circular economy monitoring framework established by the European Commission, namely: Generation of waste excluding major mineral wastes per domestic material consumption; Recycling rate of municipal waste; Circular material use rate; Gross investment in tangible goods—percentage of gross domestic product. On the basis of data series provided by the Eurostat database, our study employed a quantitative approach, by using the econometric analysis of time series. For each selected indicator, time series-specific approximation and prediction models were constructed; against this background, we were able to reveal accurate forecasts of the analysed variables, with respect to different time horizons. Detailed analysis of the data series resulting from the research proved that on the long run, there are favourable premises for improving Romania’s performance in adopting the circular economic model, on the basis of low values for the indicator “Generation of waste excluding major mineral wastes per domestic material consumption”, of an ascending trend for the indicator ”Circular material use rate” and of maintaining the values of the “Gross investment in tangible goods—percentage of gross domestic product” indicator above the EU-27 average.

Implications for Sustainability of the Joint Application of Bioeconomy and Circular Economy: A Worldwide Trend Study

The joint application of bioeconomy (BE) and circular economy (CE) promotes the sustainable use of natural resources, since by applying a systemic approach, it improves the efficiency of these resources and reduces the impact on the environment. Both strategies, which belong to the area of green economy, provide a global and integrated approach towards environmental sustainability, as regards the extraction of biological materials, the protection of biodiversity and even the primary function of food production in agriculture. The objective was to analyze the implications for sustainability of BE and CE joint application. A systematic and bibliometric review has been applied to a sample of 1961 articles, selected from the period 2004–May 2021. A quantitative and qualitative advance is observed in this field of study. The expansion of scientific production is due to its multidisciplinary nature, since it implies technical, environmental and economic knowledge. The main contribution of this study is to understand the state of research on the implications for sustainability that BE and CE have when combined, in relation to their evolution, the scientific collaboration between the main driving agents, and the identification of the main lines of research developed.

Sustainable Strategies for the Exploitation of End-of-Life Permanent Magnets

The growing production of green technologies (such as electric vehicles and systems for renewable electricity production, e.g., wind turbine) is increasing the rare earth element (REE) demands. These metals are considered critical for Europe for their economic relevance and the supply risk. The end-of-life permanent magnets are considered a potential secondary resource of REEs thanks to their content of neodymium (Nd), praseodymium (Pr) or dysprosium (Dy). The scientific literature reports many techniques for permanent magnet recovery. This work used a life cycle assessment (LCA) to identify the most sustainable choice, suggesting the possible improvements to reduce the environmental load. Three different processes are considered: two hydrometallurgical treatments (the first one with HCl and the other one with solid-state chlorination), and a pyrometallurgical technique. The present paper aims to push the stakeholders towards the implementation of sustainable processes for end-of-life permanent magnet exploitation at industrial scale.