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Water penetration and dripping in tunnels is almost always a significant problem which is usually solved with the help of a tunnel waterproofing drainage system mounted where drips and leaks are detected. Today’s drainage systems are made of foamed polyethene (PE) mats which are covered with shotcrete. These are relatively expensive, complex to install, sensitive to mechanical impact, and often have a much shorter expected lifetime than the tunnel. In this study, a new type of drainage, Rockdrain, was studied and compared with the present drainage system. The systems were evaluated with respect to technical, environmental, and economic aspects. A field test was performed with the Rockdrain system and compared with installation of a traditional system. Laboratory tests were performed on especially the different shotcrete layers used in the Rockdrain system. The environmental evaluation was performed by Life Cycle Assessment (LCA) and the economic evaluation was performed by Life Cycle Cost (LCC) analysis. The results indicate that the Rockdrain system has a good drainage function, is significantly cheaper than the current system, has a longer expected lifetime, is easier to install, and is less sensitive to mechanical impact. [ABSTRACT FROM AUTHOR]

Abstract: Single-use medical devices have been under close scrutiny for several years, especially the choice of plastic materials. Many different requirements such as medical safety, treatment functionality and efficiency, environmental performance, etc. have to be fulfilled. Today, the most commonly used materials for hydrophilic urinary catheters are polyvinylchloride (PVC) and thermoplastic polyurethane (TPU). In this research study, these two materials'' environmental performance was evaluated. In light of the knowledge gained in that study a new plastic material for use in urinary catheters was developed. The aim of the development of this new material was to design a high performance material with superior environmental performance. The newly developed plastic material is a polyolefin-based elastomer. The ecological environmental performance of the new material was evaluated and compared to the existing plastic materials. The study focused exclusively on the choice of plastic materials and their ecological environmental performance. The analysis has been performed using a system perspective and a life cycle assessment (LCA) methodology. The functional unit has been set to the treatment of one patient during one year. The results from the LCA models have been presented both in terms of direct inventory data, such as energy use and formed emissions, and in terms of the results from four different impact assessment methods. Analysis of the results based on direct inventory data, i.e. common inventory results such as energy resource uses and emissions of CO2, NOx and SO2 show an overall better environmental performance for the new polyolefin-based elastomer compared to the existing PVC and TPU plastic materials. The normalization and weighting steps in the analyzes have indicated the importance of energy resource uses and global warming as indicator for the environmental performance even if other impact categories also can play a role. In the environmental impact assessment, the polyolefin-based elastomer showed a clearly better environmental performance than the TPU material. Compared to PVC plastic material the new polyolefin-based elastomer showed an almost equivalent environmental performance. This can be mainly explained by the different materials'' energy use. The new material has thus also shown to be an environmentally good alternative to PVC if a PVC-free material is requested. Basing the plastic formula, on simple bulk plastics with low energy use in the production of single-use medical devices, has been shown to be a successful method of producing high quality products with superior environmental performance. [Copyright &y& Elsevier]

Highlights • Emissions from infrastructure construction, maintenance and operation • The relative contribution from infrastructure significant for all transport modes • Methods to allocate emissions from infrastructure Abstract In this paper, the contributions to emissions to air related to traffic infrastructure and terminals are analysed for freight transport with different modes. Data on emissions per km road or railway from existing LCA reports are adapted to a selection of road types and one type of railway line. The presented data are for air pollutants, use of primary energy and emissions of green-house gases divided into construction, maintenance and operation phases. These data are then allocated to the traffic-work produced on the infrastructure during its life span. Different allocation methods are suggested for the separate LCA-phases. The research has a focus on freight transport, why data are presented as emissions per vehicle-km for a number of truck and train types. For ports and airports, data are available per tonne of goods over quay or in- and outgoing. These results are then used to calculate the emissions added for infrastructure for freight transport chains. Examples are given showing the magnitude of emissions originating from infrastructure that can be added to tailpipe and other upstream emissions, e.g. fuel and vehicle production. In relation to tailpipe emissions the CO 2 emissions from infrastructure is typically 1–7% for road and around 17% for rail. For air and sea the results will vary significantly; for typical intra-Europe routes we find a contribution from infrastructure of about 3% for air and 21–34% for sea, in relation to emissions from the vessels. [ABSTRACT FROM AUTHOR]

The use of Zinc-coated steel (e.g. galvanized steel) in melting cycles based on Electric Arc Furnaces can increase the production of harmful dust and hazardous air emissions. This article describes a novel process to simultaneously preheat and remove the coating from the scrap surface before the melting phase. The zinc in coating is removed in the gas phase by chloride containing syngas combustion and collected in a dedicated recovery system. Two possible innovative process routes are described, which involve plastic waste pre-treatment, shredded plastic gasification/pyrolysis, steel scrap preheating and zinc recovery processes. The routes have been modeled in an integrated flowsheet, in order to allow a comprehensive simulation and optimization of the pretreatment processes. The process optimization results in possible energy savings of over 300 MJ/t of preheated scrap charged in the Electric Arc Furnace for steel production. Moreover, a comparison among different scenarios according to economic and environmental criteria has been carried out. [ABSTRACT FROM AUTHOR]