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Since sustainable scheduling is arousing increasing attention from many manufacturing enterprises and energy consumption is a core problem regarding sustainability, the purpose of this paper is to develop an energy-efficient scheduling method to fulfill material delivery tasks in mixed-model assembly lines. In this research, the objective of minimizing the energy consumption is jointly integrated with the operational criterions when executing material delivery tasks. Owing to the NP-hard nature of the considered problem, a Taboo enhanced Particle Swarm Optimization (TEPSO) algorithm is developed to solve the multi-objective problem. Several improving strategies are applied to enhance the performance of the proposed TEPSO in order to obtain a stronger local search capability and faster search speed. The performance of the proposed TEPSO algorithm is evaluated by comparing with two other high-performing multi-objective optimization methods. Computational experiments are conducted in order to test and verify the effectiveness and efficiency of the proposed TEPSO algorithm. The achievements reported in this paper might be inspiring for further studies on energy-efficient production scheduling. [ABSTRACT FROM AUTHOR]

Cities are mainly responsible for greenhouse gas (GHG) emissions in the atmosphere and thus for climate change. The European Union (EU) set up a series of strategies and policies to facilitate the elaboration of climate change mitigation and adaptation of urban plans. To do this, it is necessary to measure the city's GHG emission level. The Urban Carbon Footprint (UCF) and its derivation, the Relative Carbon Footprint (RCF), represent the most appropriate tools for obtaining this important information. The present paper applies these indicators to a small city (150 000 inhabitants) located in Southern Italy, a novelty for academic studies, which usually concentrate on megacities. The study focuses only on CO 2 emissions, as these represent 90% of the total GHGs released in urban areas. The findings showed that in 2015 the total UCF was equal to 288 ktCO 2 , specifically deriving from electricity and natural gas consumption. Moreover, Residential, Industry and Tertiary are the most carbon-intensive economic sectors. The RCF was equal to 0.30; the city emission levels were lower than the national average. Therefore, the municipality represents a typical “net-consumer” community, dominated by homes with territorial emissions due to consumption and characterized by a low number of industries and an average income per capita that is 50% lower than the national one. Starting from these results, the study proposed an urban action plan according to the EU mitigation and adaptation policies. This plan could help the local government improve its environmental sustainability, even if more public city-level data is required for a more comprehensive analysis. Finally, it would be more appropriate for all actions to be aligned under a unique policy process to seize the opportunity to link the various local intervention policies from different fields, taking into account their existing funding, tools, processes, and resources. Capitalizing on the adaptation/mitigation connection will allow municipalities to leverage their climate change action efforts and accelerate progress toward their climate and energy goals. [ABSTRACT FROM AUTHOR]

Warm Mix Asphalt (WMA) has recently become an attractive alternative in pavement engineering due to its potential for significant reduction in energy consumption and carbon footprint of asphalt industry; however, concerns have been raised regarding durability of material and potential to moisture damage due to lower mixing and compaction temperatures. Furthermore, steel slag which is mostly disposed in landfills as waste material could be an appealing option as substitute of natural aggregates for asphalt concrete (AC) production because of its adequate affinity with asphalt binder. The aim of this study is therefore, to assess whether the integration of basic oxygen furnace (BOF) steel slag into Sasobit WMA technology would indicate satisfactory performance in terms of moisture susceptibility. This paper also examines if BOF slag WMA mixture can provide acceptable mechanical performance to be used as a more sustainable approach for pavement construction. To capture short-term moisture damage resistance of BOF slag WMA, specimens prepared with two Sasobit dosages were subjected to two different testing methods. Modified Lottman test and boiling water test using an image analysis technique were performed to compare moisture susceptibility and stripping resistance of BOF slag WMA and HMA (hot mix asphalt) samples with conventional mixtures. Dynamic creep test, Hamburg wheel-track device and resilient modulus test were then conducted on specimens to evaluate mechanical behavior of BOF slag WMA in comparison with BOF slag HMA and another type of WMA mixture prepared with natural aggregates. Findings showed that BOF slag WMA provided significant resistance to short-term moisture damage and therefore, could be considered as durable bituminous mixture when compared to conventional asphalt mixtures. Furthermore, BOF steel slag HMA/WMA exhibited superior mechanical behaviors compared to limestone HMA/WMA mixtures, implying that steel slag could be an effective alternative as pavement material. [ABSTRACT FROM AUTHOR]

Resource, economic, and environmental impacts are three major factors in the evaluation of industrial processes. All of them might imply certain contributions of ecosystems services. A comprehensive accounting of these factors is critical to sustainability assessment of industrial activities at the ecological scale. Ecological Cumulative Exergy Consumption (ECEC) analysis is a promising approach to address these issues. However, the current knowledge on ECEC is incomplete, especially in economic investment and environmental impact. In this paper, ECEC analysis is extended to quantify purchased resources and pollutant emissions of industrial production. Accordingly, an extended ECEC framework is proposed, integrating the resource, economic, and environmental factors. Furthermore, for better understanding of sustainability, a concept of Ecological Life Cycle Cost (ELCC) is put forward, revealing the relationship between the ECEC and traditional economic evaluation. Finally, a case study of China's raw coal production is used to illustrate the features of these proposed frameworks. The ECEC and ELCC analyses indicate the great ecological influence of raw coal which has been underestimated by the traditional assessment approaches. [ABSTRACT FROM AUTHOR]

Battery demand is estimated to growth at a 25% annual rate, to reach a volume of 2600 GWh in 2030. Recovering critical raw materials from end-of-life batteries is now mandatory to limit the need of primary raw materials in the long-term. However, recycling of lithium-ion batteries (LIBs) is still in its early stage. Many technologies have been proposed, that consist of a combination of mechanical processing, often after thermal pre-treatment, ended up to hydrometallurgical or pyrometallurgical processing. All these methods have several pros and cons in terms of applicability, safety, environmental impact, eventual recovery efficiency of the components, and economic factors. In this frame, the evaluation of the sustainability of the proposed technologies plays a fundamental role in selecting the most suitable approaches able to support material supply for batteries, identifying the major solutions to optimize the end-of-life management strategies for LIBs, in the perspective of a circular economy context. However, LCA was developed to evaluate commercially mature technologies. This paper aims to propose and discuss, for the first time, the sustainability of 33 different technologies available in literature for LIBs recovery, even if developed only at laboratory level, by a screening approach, preliminary to LCA analysis. For this purpose, ESCAPE (standing for Evaluation of Sustainability of material substitution using CArbon footPrint by a simplified approach) tool based on the calculation of embodied energy and carbon footprint is used. Based on ESCAPE analysis results, this work shows and discusses the parameters that affect the technologies sustainability (thermal and mechanical treatments and chemicals and water use). The results, in accord with preliminary available LCA data, indicate that chemicals and ultrapure water consumption are the most energy-intensive processes drivers, showing that pyrometallurgy can limit carbon footprint and energy consumption in comparison to hydrometallurgy. Finally, by using the ESCAPE index, it is shown that some technologies may be improved for example by using industrial water instead of ultrapure water and/or by recycling the chemicals used for leaching steps. In summary it is shown that ESCAPE tool can be used in supporting eco-design strategies with the aim to facilitate the understanding of environmental implications of proposed LIBs recovery technologies and to focalize the research toward the more promising ones. [Display omitted] • Sustainability analysis of 33 technologies to recover spent LIBs is proposed. • The processes steps are evaluated in terms of embodied energy and carbon footprint. • LIBs recycling processes should aim for a better water management and leachants recovery. [ABSTRACT FROM AUTHOR]