1,721,108 research outputs found
Circular Economy in Construction and Demolition Waste: an environmental and economic opportunity
No full textEnvironmental and safety risk assessment for sustainable circular production: Case study in plastic processing for fashion products
Full text linkEven if sustainability and circularity are the most challenging goals today, industrial waste minimization is rarely discussed and practical methods to reduce risks related to hazardous waste in manufacturing processes are not frequently applied yet. The case of Italian company specialized in plastic processing for fashion products, has the chance to design and test a new integrated methodology to reduce the risks for ecosystem and workers associated to hazardous waste. Focusing the attention to standard operations, extraordinary conditions, and emergency situations, all activities included in waste collection, storage and transport are identified and the risks associated to the environmental impacts and the occupational health&safety are analysed. Research results demonstrate the opportunity to adopt one method to analyse both environmental and health&safety risks associated to activities and conditions involved in industrial waste management. The case study confirms the relevance of integrated approaches and the necessity of simplified tools to support companies in adopting integrated risk management
Simulation of phase explosion in the nanosecond laser ablation of aluminum
No full textVaporization, spallation and phase explosion are considered to be the main mechanisms contributing to the nanosecond laser ablation of metals. The theory of homogeneous nucleation, together with the dynamics of target heating, allows a space-time resolved simulation of the phase explosion mechanism. The thermal phenomena occurring at the target surface are studied within the framework of a thermodynamic continuum approach. A 20 ns laser pulse of variable fluence and Gaussian time dependence was assumed. The temperature profile in the target external layers is studied through the heat diffusion equation. The vaporization from the surface is modeled assuming unsteady adiabatic expansion (UAE) of the vapor and a Monte Carlo (MC) method is used to describe the formation of liquid nanodroplets through phase explosion. Liquid nanodroplets in the ablated material are studied at different laser fluences. The size distribution of the nanodroplets formed in the phase explosion process is here reported and connections with experiments are discussed
ENVIRONMENTAL PROFILE OF ANAEROBIC AND SEMI-AEROBIC LANDFILLS WITHIN SUSTAINABLE WASTE MANAGEMENT: AN OVERVIEW
No full textThe new perspective of circular economy accelerates the efforts to increase reuse and recycling of products and reduce the need of resources. Although the quantity of waste reaching the end-of-life has decreased, landfills can't be eliminated from the waste management systems (WMS) since the current treatment processes still produce unrecyclable materials. Anaerobic landfills have great environmental impacts due to the long-term emissions, therefore, to reach a more sustainable waste management less impacting alternatives are being implemented. Semi aerobic landfills can reduce the environmental burdens by enhancing waste stabilization with natural air flow inside the landfill body through the leachate collection pipes. The presence of aerobic areas implies biogas with less methane and leachate with lower pollutant concentrations. The research goal is to deepen the evidence that the semi-aerobic landfills are environmentally preferable to traditional anaerobic landfills, by considering the scientific information published in international peer-reviewed journals from 2000 to 2022. To obtain comprehensive answers to the research question, papers using the life cycle assessment (LCA) methodology are included in the review, with the aim of understanding what the environmental profiles of traditional and semi-aerobic landfill are when all life cycle phases are considered. The results clarify what the main contributions to environmental impacts of these two types of landfills are. The review only partially demonstrates the environmental convenience of semi-aerobic landfill. Instead, it reveals a lack of papers analyzing the comparison between different landfill technologies, suggesting new research perspectives to optimize the sustainability of final treatment solutions in WMS
Arrangement and optimisation of natural gas compression station driven by gas turbines in an off-shore extraction station
No full textIn this paper, a methodology for the optimization of a single
off-shore gas compression station is developed. The station is
composed of three gas turbines, each one driving a centrifugal
compressor. The study concerns the feasibility of the most
suitable arrangement to face the depletion of wells and the
consequent reduction of the head top pressure. Once the
arrangement is chosen, an optimization procedure is developed
and carried out. The procedure, which is aimed at obtaining
either high production rates or good station efficiency, is based
on knowledge of the centrifugal compressor characteristics and
on the availability of gas turbine thermodynamic cycle
program, the latter allowing the definition of the machine actual
operating state
Il Sistema di Gestione Ambientale. Linee guida all'applicazione della norma UNI EN ISO 14001:2004
No full textExternal communication on legal compliance by Italian waste treatment companies
No full textNumerous studies discuss the role of environmental reporting to communicate legislative compliance, but few papers focus on the waste treatment sector, where clear communication is crucial for companies to legitimize management strategies. To fill this gap, an explorative study focusing on solid waste treatment by Italian companies registered with the European Environmental Management and Audit Scheme was conducted. The aim of the research is to discover if and how these companies inform external stakeholders about compliance with environmental legislation in (1) assessing environmental aspects, (2) planning environmental objectives, and (3) monitoring environmental performance. Forty-nine Italian companies were selected, and their Environmental Statements were analyzed. The results prove that environmental reporting of Italian companies frequently includes an explicit reference to legislative compliance in planning environmental objectives; however, rarely legal compliance is assumed as criterion to assess environmental aspects and to monitor environmental performance. Comparing these results with other recent studies, some conflicting findings emerge: the risks derived by the lack of explicit information on legal compliance in environmental reporting are discussed, and recommendations to assure transparency and credibility of reporting are underlined. Final propositions and future perspectives for practitioners and scientists conclude the paper, which contributes to the debate about the adequacy of external communication of environmental management systems in waste treatment sector
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