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Thermal spraying (TS) is one of the main processes for obtaining surfaces with the desired protective properties in various industrial applications. TS is an energy-intensive treatment required to heat the application material and consumes different resources. To assess the environmental impact of TS, it becomes necessary to integrate an approach that jointly analyses and evaluates the economic and environmental variables influencing the system. The concept of eco-efficiency (EE) added to the TS process allows for assessing the environmental and economic condition through the survey and application of eco-indicators. The lack of an EE evaluation model for TS processes was identified based on literature searches. Thus, the overall objective of this work is to propose a conceptual model to evaluate the EE of TS treatment, selecting environmental and economic indicators considered more impactful in the process. The model developed consists of three main steps: (i) the input and output indicators (environmental and economic) are identified by applying the Analytic Hierarchy Process (AHP) method; (ii) the structure to be employed in the model is defined; and (iii) the Data Envelopment Analysis (DEA) model is applied to define the EE evaluation form. The proposed model consists of clear and easy-to-follow steps for evaluating the EE of spraying processes, filling the gap found in the literature. The use of DEA allowed the integration of the environmental and economic indicators obtained from the TS processes to generate important insights for evaluating EE. The results prove the model's effectiveness in identifying the EE results for each analysed unit of the TS process. The model has provided an evaluation consistent with the existing studies, and the EE scores were assessed according to twenty-one decision-making units (DMUs) allowing the identification of the most eco-efficient DMUs concerning TS processes.

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The objective of this study was to apply simulation and genetic algorithms for the economic and environmental optimization of the reverse network (manufacturers, waste managers, and recyclers in Sao Paulo, Brazil) of waste from electrical and electronic equipment (WEEE) to promote the circular economy. For the economic evaluation, the reduction in fuel, drivers, insurance, depreciation, maintenance, and charges was considered. For the environmental evaluation, the impact of abiotic, biotic, water, land, air, and greenhouse gases was measured. It was concluded that the optimized structure of the WEEE reverse chains for Sao Paulo, Brazil provided a reduction in the number of collections, thus making the most of cubage. It also generated economic and environmental gains, contributing to the strategic actions of the circular economy. Therefore, the proposed approach is replicable in organizational practice, which is mainly required to meet the 2030 agenda of reducing the carbon footprint generated by transport in large cities. Thus, this study can guide companies in structuring the reverse WEEE chains in Sao Paulo, Brazil, and other states and countries for economic and environmental optimization, which is an aspect of great relevance considering the exponential generation of WEEE.

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The transition to a neutral carbon and sustainable urban water cycle requires improving eco-efficiency in wastewater treatment processes. To support decision-making based on eco-efficiency evaluations, reliable estimations are fundamental. In this study, the eco-efficiency of a sample of 109 WWTPs was evaluated using efficiency analysis tree method. It combines machine learning and linear programming techniques and therefore, overcomes overfitting limitations of non-parametric methods used by past research on this topic. Results from the case study revealed that optimal costs and greenhouse gas emissions depend on the quantity of organic matter and suspended solids removed from wastewater. The estimated average eco-efficiency is 0.373 which involves that the assessed WWTPs could save 0.32 €/m3 and 0.11 kg of CO2 equivalent/m3. Moreover, only 4 out of 109 WWTPs are identified as eco-efficient which implies that the majority of the evaluated facilities can achieve substantial savings in operational costs and greenhouse gas emissions.

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El espacio de comedores son una forma de garantizar el acceso a alimentos seguros, saludables y medio ambientalmente responsables para los estudiantes universitarios. Objetivo. Este estudio tuvo como objetivo caracterizar los estándares del menú, a partir de la evaluación de la calidad nutricional y del impacto en el medio ambiente por los insumos utilizados para su elaboración por un Comedor Universitario (CU) en Uruguay. Materiales y métodos. Se trató de un estudio de caso retrospectivo, relativo al año 2021. Las variables evaluadas fueron a) cantidad total de alimento comprado en kilogramos (kg); b) cantidad en kilocalorías (kcal) e impactos ambientales por: c) generación de residuos; d) huella hídrica (HH); y e) gases de efecto invernadero (GEI). También se realizaron cálculos para evaluar la ecoeficiencia (EE). Resultados. El CU sirvió 33.740 comidas en 2021, de las cuales el 87,1% fueron almuerzos. De los 78 tipos de alimentos comprados, 41 de ellos representaron el 93,17% del total en kilogramos. En la calidad nutricional, menos del 10% se clasificaron como alimentos procesados o ultraprocesados. En la evaluación de aspectos nutricionales e impactos ambientales, los alimentos de origen animal representaron el 26,52% del total en kg y el 69,78% de los HH. Un alimento de origen vegetal tuvo el mayor impacto de GEI debido a su origen. En cuanto a la EE, la valoración general mostró un resultado de 0,0626 para los alimentos de origen animal y 0,3838 para los de origen vegetal. Conclusiones. Corresponde a los servicios de alimentación para colectividades considerar, en la planificación del menú, además de la calidad nutricional y sanitaria de la oferta alimentaria, los impactos ambientales que estas genera(AU)

The canteens are a way to guarantee access to safe, healthy and environmentally responsible food for university students. Objective. The purpose of this research was to characterize the menu standards, based on the evaluation of the nutritional quality and the environmental impact of the inputs used for its preparation by a university canteen in Uruguay. Materials and methods. This was a retrospective case study, relating to the year 2021. The variables evaluated were a) total amount of food purchased in kilograms (kg); b) quantity in kilocalories (kcal) and environmental impacts due to: c) waste generation; d) water footprint (WF); and e) greenhouse gases (GHG). Calculations were also performed to assess eco-efficiency (EE). Results. The university canteen served 33,740 meals in 2021, of which 87.1% were lunches. Of the 78 types of food purchased, 41 of them represented 93.17% of the total in kilograms. In nutritional quality, less than 10% are classified as processed or ultra-processed foods. In the evaluation of nutritional aspects and environmental impacts, foods of animal origin represented 26.52% of the total in kg and 69.78% of WF. A vegetal based food had the highest GHG impact due to its origin. Regarding the EE calculations, the general assessment showed a result of 0.626 for foods of animal origin and 0.3838 for those of vegetable origin. Conclusions. It corresponds to the food services for communities to consider, in the planning of the menu, in addition to the nutritional and sanitary quality of the food offer, the environmental impacts that it generates(AU)

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Eco-efficiency assessment of municipal solid waste (MSW) suppliers is a useful tool in the transition to a circular economy. Furthermore, it provides evidence of the economic and environmental performance of municipalities that can be used for decision-making and/or elaboration of regulatory policies. In this study, eco-efficiency scores were computed for a sample of 140 Chilean municipalities in the provision of MSW services. In doing so, the stochastic semi-parametric envelopment of data method was applied. It is a novel technique which overcomes the limitations of parametric (stochastic frontier analysis) and non-parametric (data envelopment analysis) methods previously employed to evaluate the eco-efficiency of MSW services. The average eco-efficiency of the 140 assessed municipalities was 0.332 which indicates that they could save 66.8% of their operational costs and recycling the same amount of waste. Moreover, 61.4% of the evaluated municipalities presented an eco-efficiency score which was lower than 0.4, whereas the other municipalities (38.6% of the sample) exhibited an eco-efficiency which raged between 0.4 and 0.80. Hence, none of the municipalities assessed was identified as eco-efficient which, implies that there is room for all municipalities to reduce operational costs in the management of MSW. Population density, tourism and location of the municipality were identified as factors influencing the eco-efficiency of the municipalities in MSW management.

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There is a growing demand for the adoption of cyclical processes in the fashion industry. The trends point to the reuse of cellulose from cotton fibres, obtained from industrial waste, as a substitute to the former linear processes of manufacturing, sale, use, and discarding. This study sets up to explore and assess the economic and environmental gains from the mechanical shredding of cellulose in cotton fabrics in a textile company, identifying the circularity associated with the adoption of such methods. The study resorted to a case study methodology building on interviews and observation. For the environmental estimations, the study employed the material intensity factor tool, and for the economic evaluation the study uses the return on investment. The study also offers an estimation of the circularity of the processes that were implemented. The adoption of the mechanical shredding for cotton cellulose generated economic gains of US$11,798,662.98 and a reduction in the environmental impact that amounts to 31,335,767,040.26 kg including the following different compartments: biotic, abiotic, water, air, and erosion. The findings suggest the existence of opportunities for the circular economy in the textile sector of about 99.69%, dissociated to the use of mechanical recycling, while limited by the consumption of electrical energy and lubricants in the recycling process, leading the way to a circular economy.

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The aim of this study was to analyse how to ensure that medium- and long-term waste recovery goals can be achieved in Brazilian cities, based on the incorporation of viable and accessible technology. The identification of the strengths of the Brazilian cities with better (dry and wet) waste recovery rates allowed different strategies to be proposed for João Pessoa (the city selected as a case study). Those strategies were based on the improvement of (1) the selective collection of the recyclable dry waste fraction, (2) the material recovery facility to increase the recovery of recyclable dry waste fraction to be recycled and/or wet waste fraction to be composted, and finally (3) the working conditions of waste workers. A combination of these improvement strategies at two different levels of implementation (partial and total) allowed the definition of 14 alternative scenarios, which were analysed from an eco-efficiency perspective (environmental vs. economic). After analysing the evolution over time of the alternative scenarios proposed, the proposal that was finally selected was based on the initial implementation of a mechanical biological and composting facility capable of handling up to 50% of the mixed municipal solid waste collected by 2023 with a material recovery efficiency of 30%. From there, the efficiency of the mechanical biological and composting facility should increase up to 60% to achieve the waste recovery goals by 2034 (management of 60% of the mixed waste collected). This rate has not yet been reached in any of the Brazilian mechanical biological and composting facilities analysed, so the reduction in the amount of waste generated and the increase in the selective separation of waste at source are identified as key elements to be able to fulfil the long-term goals. The approach used in the case study provides guidelines for application in other geographical contexts.

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Aiming to assist the environmental sustainability of the Brazilian Amazonian agriculture, this article developed an eco-efficiency index, indicating the possible limits to maximize economic and environmental objectives, taking into account the best practices in the municipalities of the region. Shadow prices of degraded areas and forest preservation were also estimated using data envelopment analysis with directional distance functions. The results indicate that, on average, the analyzed municipalities are able to expand the production and the forest areas by 38% and reduce degraded areas and their inputs in the same proportion. The shadow prices allowed the estimation of the annual opportunity cost of the degraded areas and the preservation of the forest on the farms. The first, US$ 3,131,571, represented 0.04% of the annual output value, indicating that the internalization of that cost should be a low burden for the eco-efficient producer. The second, the total cost of preserving 80% of the area of property, represented US$ 120,890,662 or 1.7% of the annual income of the biome producers studied. Therefore, the main conclusion of this work is that the internalization of negative and positive externalities of agricultural production in the Amazonian biome does not make agricultural production economically unfeasible in the region. In addition, the reimbursement of damages avoided by carbon sequestration, through the Clean Development Mechanism (CDM) established by the Kyoto Conference, should further increase the economic and environmental sustainability of agriculture in the area.

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This paper presents an eco-efficiency analysis of five scenarios for treating a petrochemical unit effluent defined sequentially to increase the water reuse rate to the limit condition of Zero Liquid Discharge perspective. The base process, consisting of reverse osmosis, an evaporator and crystallizer, displayed pretreatment alternatives the addition of antifouling agents, desupersaturation of barium ions and coprecipitation of low solubility salts to increase osmosis efficiency. The eco-efficiency analysis applied the life cycle approach to verify environmental and energy performances and determined the costs of the treatment unit installation and operation for a time horizon of 9.5 years. The pretreatment increased water recovery during osmosis from 84% to over 97%. The environmental-energetic analysis indicated a strong influence of electric energy, consumed mainly during the thermal stages of the treatment, and of the chlorine-derived compounds used in the pretreatment. Also due to pre-treatment, it was possible to reduce impacts in terms of Global Warming Potential by up to 59%, and in Primary Energy Demand by 64% for the best scenario. The economic analysis depicted a significant influence of operating costs, and the electricity consumed in the processes is responsible for the largest share of expenses. The reuse water presented a cost ranging between US$ 1.08/m3 and US$ 1.80/m3. The systems with pretreatment by coprecipitation with Ca(OH)2 and CaCO3 and monoacids to adjust the pH of the final effluent showed to be more eco-efficient than the other options under analysis.

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In the circular economy context, improving the eco-efficiency of the management of municipal solid waste (MSW) occupies a prominent role. The aim of this study was to evaluate the eco-efficiency of MSW services provided by a sample of 142 Chilean municipalities using data envelopment analysis (DEA), a method that integrates both economic and environmental variables into a single performance index. This study also investigated whether the MSW facilities are affected by economies of scale. In a second stage of analysis, the effects of some exogenous variables on the eco-efficiency of MSW services were explored. The results demonstrated that 92.3% of the municipalities evaluated were not eco-efficient and presented notable room for improvement as the average eco-efficiency score was 0.58. In addition, 40.4% of the municipalities presented negative economies of scale; i.e. their operational size was not optimum and joint organization of MSW management systems should be promoted. Finally, the population served, population density, tourism and waste generated per capita were shown to have a significant impact on the eco-efficiency of MSW services. The results of this study will be beneficial for policymakers to formulate effective public policies to make the provision of MSW services more cost- and environmentally effective.

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Based on the panel data of 134 counties (cities and districts) from 1998 to 2017, the temporal-spatial variation characteristics and influencing factors of agricultural eco-efficiency in Shandong Province were analyzed by using various methods, such as the super-efficiency SBM (slacks-based measure) model considering undesired output and the STIRPAT (stochastic impacts by regression on population, affluence, and technology) model, which helps clarify the improvements needed for agricultural eco-efficiency and provides a basis for the development of ecological agriculture in Shandong Province. Results showed the following: (1) During 1998-2017, the agricultural eco-efficiency of Shandong Province showed a fluctuating increasing tendency, but the overall efficiency value wasrelatively low. (2) The agricultural eco-efficiency of Shandong Province had a significant regional disparity, and its spatial agglomeration gradually weakened. The spatial distribution had a sporadic distribution of high value areas at first and then gradually formed the low-high-low-high zonal distribution from west to east. (3) The net income per capita of farmers and the added value of the primary industry had a significantly positive correlation with the agricultural eco-efficiency of Shandong Province, while the mechanization level, the planting area per capita, the level of financial support to agriculture and the planting structure exhibited a mainly negative correlation with the agricultural eco-efficiency of Shandong Province. Moreover, the added value of the primary industry and the financial support to agriculture in the 0.75 quantile had no significant influence on the agricultural eco-efficiency of Shandong Province, and the planting structure in the 0.25 and 0.75 quantiles also had no significant influence.(AU)

Com base nos dados do painel de 134 municípios (cidades, distritos) na província de Shandong de 1998 a 2017, as características de variação espacial e temporal da ecoeficiência agrícola na província de Shandong foram analisadas usando vários métodos, como o modelo SBM (Medida baseada EM estacas) supereficiente. Considerando indesejados produção e modelo STIRPAT (Impactos estocásticos da regressão da população, da afluência e da tecnologia), ajudará a esclarecer a direção da melhoria da eco eficiência agrícola na província de Shandong e fornecerá uma base para o desenvolvimento da agricultura ecológica. Os resultados mostraram que (1) em 1998-2017, a ecoeficiência agrícola da província de Shandong mostrou uma tendência ascendente na flutuação, mas o valor geral da eficiência foi baixo. (2) A distribuição espacial da distribuição esporádica inicial da área de alto valor se formou gradualmente de oeste para leste, distribuição zonal baixo-alto-baixo-alto (3) O lucro líquido per capita dos agricultores e o valor acrescentado da indústria primária foram significativamente correlacionados positivamente com a ecoeficiência agrícola da província de Shandong. O nível de mecanização, a área de plantio per capita, o apoio financeiro ao nível agrícola e a estrutura de plantio, entre eles, o valor acrescentado da indústria primária e o apoio financeiro à agricultura em 0,75 quantil, a estrutura de plantio em 0,25 e 0,75 quantil na ecoeficiência agrícola da província de Shandong não é significativa.(AU)

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ABSTRACT: Based on the panel data of 134 counties (cities and districts) from 1998 to 2017, the temporal-spatial variation characteristics and influencing factors of agricultural eco-efficiency in Shandong Province were analyzed by using various methods, such as the super-efficiency SBM (slacks-based measure) model considering undesired output and the STIRPAT (stochastic impacts by regression on population, affluence, and technology) model, which helps clarify the improvements needed for agricultural eco-efficiency and provides a basis for the development of ecological agriculture in Shandong Province. Results showed the following: (1) During 1998-2017, the agricultural eco-efficiency of Shandong Province showed a fluctuating increasing tendency, but the overall efficiency value wasrelatively low. (2) The agricultural eco-efficiency of Shandong Province had a significant regional disparity, and its spatial agglomeration gradually weakened. The spatial distribution had a sporadic distribution of high value areas at first and then gradually formed the "low-high-low-high" zonal distribution from west to east. (3) The net income per capita of farmers and the added value of the primary industry had a significantly positive correlation with the agricultural eco-efficiency of Shandong Province, while the mechanization level, the planting area per capita, the level of financial support to agriculture and the planting structure exhibited a mainly negative correlation with the agricultural eco-efficiency of Shandong Province. Moreover, the added value of the primary industry and the financial support to agriculture in the 0.75 quantile had no significant influence on the agricultural eco-efficiency of Shandong Province, and the planting structure in the 0.25 and 0.75 quantiles also had no significant influence.

RESUMO: Com base nos dados do painel de 134 municípios (cidades, distritos) na província de Shandong de 1998 a 2017, as características de variação espacial e temporal da ecoeficiência agrícola na província de Shandong foram analisadas usando vários métodos, como o modelo SBM (Medida baseada EM estacas) supereficiente. Considerando indesejados produção e modelo STIRPAT (Impactos estocásticos da regressão da população, da afluência e da tecnologia), ajudará a esclarecer a direção da melhoria da eco eficiência agrícola na província de Shandong e fornecerá uma base para o desenvolvimento da agricultura ecológica. Os resultados mostraram que (1) em 1998-2017, a ecoeficiência agrícola da província de Shandong mostrou uma tendência ascendente na flutuação, mas o valor geral da eficiência foi baixo. (2) A distribuição espacial da distribuição esporádica inicial da área de alto valor se formou gradualmente de oeste para leste, distribuição zonal " "baixo-alto-baixo-alto"" (3) O lucro líquido per capita dos agricultores e o valor acrescentado da indústria primária foram significativamente correlacionados positivamente com a ecoeficiência agrícola da província de Shandong. O nível de mecanização, a área de plantio per capita, o apoio financeiro ao nível agrícola e a estrutura de plantio, entre eles, o valor acrescentado da indústria primária e o apoio financeiro à agricultura em 0,75 quantil, a estrutura de plantio em 0,25 e 0,75 quantil na ecoeficiência agrícola da província de Shandong não é significativa.

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Currently, the concern with the environment is increasing and organizations seek solutions to preserve nature and at the same time earn higher profits or competitiveness. For this, they make frequent use of structured procedures in order to reduce their costs and expenses. However, it has not been always considered the environmental performance related to the financial performance of these processes. Therefore, this study aimed to investigate the relationship between environmental performance measured by eco-efficiency level with the financial performance of small and medium textile manufacturing companies. This study was done through a survey conducted in the interest of research companies in the state of Paraná in Brazil, where financial and environmental performance indicators were measured. The data analysis and validation of the hypotheses proposed, to some extent showed a surprising result because the larger the size of the company, the worst its environmental performance measured by their eco-efficiency level. On the other hand, it was not possible to identify a statistically significant relationship between environmental and financial performances of the companies surveyed. Therefore, it is concluded that this study is in line with those authors who claim not to be possible to establish a direct relationship between environmental and financial performances of companies, in opposition of another group of authors who claim contrariwise.

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Operations management tools are critical in the process of evaluating and implementing action towards a low carbon production. Currently, a sustainable production implies both an efficient resource use and the obligation to meet targets for reducing greenhouse gas (GHG) emissions. The carbon footprint (CF) tool allows estimating the overall amount of GHG emissions associated with a product or activity throughout its life cycle. In this paper, we propose a four-step method for a joint use of CF assessment and Data Envelopment Analysis (DEA). Following the eco-efficiency definition, which is the delivery of goods using fewer resources and with decreasing environmental impact, we use an output oriented DEA model to maximize production and reduce CF, taking into account simultaneously the economic and ecological perspectives. In another step, we stablish targets for the contributing CF factors in order to achieve CF reduction. The proposed method was applied to assess the eco-efficiency of five organic blueberry orchards throughout three growing seasons. The results show that this method is a practical tool for determining eco-efficiency and reducing GHG emissions.

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O artigo discute limites, alternativas e desafios da gestão ambiental nas sociedades contemporâneas inseridas no capitalismo globalizado a partir de uma análise crítica apoiada em autores das ciências sociais, da ecologia política e da saúde coletiva. Para isso, sistematizamos o significado da gestão ambiental hegemônica em sua vertente da ecoeficiência e seus limites para o enfrentamento dos riscos ambientais e para a construção de processos e sociedades mais democráticos. Construímos quatro tipos ideais de cenários envolvendo possíveis combinações entre gestão ambiental e democracia. Este modelo serviu de base, juntamente com trabalhos acadêmicos e a experiência teórica e militante dos autores, para uma reflexão sobre as características atuais e as tendências futuras de gestão ambiental e democracia, com ênfase na realidade latino-americana, mais especificamente na brasileira. Por fim, discutimos possibilidades de transformação social a partir das contradições e alternativas emancipatórias decorrentes das confrontações entre tendências hegemônicas do mercado e contra-hegemônicas provenientes de utopias e movimentos sociais, estas assumindo princípios da justiça ambiental, da economia solidária, da agroecologia e da sustentabilidade, bem como da construção de novas epistemologias.

This article discusses the limits, alternatives and challenges of environmental management in contemporary globalized capitalist societies. It is based on a critical analysis supported by authors from social sciences, political ecology and public health. To this end, we systematize the meaning of hegemonic environmental management in terms of eco-efficiency and its limits to tackle environmental risks and construct democratic processes and societies. We developed four ideal scenarios involving possible combinations of environmental management and democracy. This model served as a base, together with academic studies and the theoretical and militant experience of the authors, for a reflection on the current characteristics and future trends of environmental management and democracy, with emphasis on the reality of Latin America, specifically Brazil. Lastly, we discuss possibilities for social transformation taking into consideration the contradictions and emancipatory alternatives resulting from confrontations between hegemonic tendencies of the market and counter-hegemonic utopias and social movements. The latter assume principles of environmental justice, economic solidarity, agro-ecology and sustainability as well as the construction of new epistemologies.

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