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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
121

A Life Cycle Comparison of Light-Frame Wood and Insulated Concrete Form Building Envelopes: Energy Use and Green House Gases

Matthews, Sherman Authur 01 August 2011 (has links)
Given the building sector’s substantial contribution to global energy use and green house gas (GHG) emissions, it is of great importance that only the most effective building envelopes are utilized. Conventional light-frame wood building envelopes are highly popular due to their ease of construction and building economy; however the life cycle performance of the building envelope is often overlooked when this selection is made. Although insulated concrete form (ICF) building envelopes generally require a substantially higher embodied energy input, it should be considered that improvements during a building’s operation phase can offers significant energy returns, ultimately reducing the building’s life cycle energy use and GHG intensity. Therefore, an assessment is conducted regarding the life cycle energy use and GHG intensity of the ICF building envelope, in addition to two light-frame wood building envelopes; the average light wood frame envelope (U.S. Department of Energy, 2007), and a more highly insulated wood frame envelope. The operation phase of the building envelopes proves to be of greatest significance, as it is attributed to 95- 97% of the total life cycle energy use, and 93-96% of life cycle GHG emissions, assuming a 100 year life cycle. Ultimately, the life cycle performance of the ICF building envelope is superior to the two wood frame envelopes due to its improvements in the operation phase. The ICF building envelope has a life cycle energy requirement of 11% to 14% less than the two light-frame wood envelopes, and a 10% to 12% lower life cycle GHG intensity. Although the increased thermal resistance certainly contributes to the superior life cycle performance of the ICF envelope, the improved infiltration leakage area of the envelope is key to its operational performance, and subsequently to its improved life cycle performance. End of life energy use for the demolition, recycle, and disposal of the building envelopes is nearly negligible, as it is attributed to less than 0.3% of the life cycle energy for any of the envelope scenarios.
122

Life Cycle Thinking in Environmentally Preferable Procurement

Hochschorner, Elisabeth January 2008 (has links)
Products generate environmental impacts during their life cycle by consuming raw materials and energy, releasing emissions and producing waste. A procurement organisation can be a considerable driving force for more environmentally friendly products e.g. by requiring that products meet certain environmental criteria. The scope for environmental consideration when procuring materiel can be limited by lack of reliable information about the environmental characteristics of the product or service. Different types of tools (e.g. eco-labels, guidelines, checklists and tools for environmental assessment) can contribute some knowledge and help identify environmentally preferable products. This thesis focuses on use of tools for environmental consideration in Swedish defence acquisition but the results are also relevant for other organisations, since the procurement process analysed is rather general and the legal requirements are similar for other public organisations in Europe. A Swedish government decision in 1998 requires the Swedish Armed Forces (SAF) and Defence Materiel Administration (FMV) to take environmental consideration in all phases of the acquisition process. The importance of a life cycle perspective is stressed in several SAF and FMV environmental documents. The starting point of this thesis was that environmental consideration should be taken in the Swedish acquisition of defence materiel, considering the whole life cycle of products, with the aim of formulating proposals on environmentally friendly procurement. Some Ecodesign tools were reviewed and evaluated, two methods for simplified Life Cycle Assessment (LCA) were compared, tools and methodology were recommended, and used to study military materiel, and environmental Life Cycle Costing (LCC) was examined. In environmental work lacking a life cycle perspective, the most significant aspects risk being overlooked. Use of quantitative and/or simplified LCAs and inclusion of environmental costs in LCC are therefore recommended. LCA proved an appropriate tool for involving environmental consideration in the acquisition process, since it focuses on products and their life cycle. The MECO method proved best for simplified LCA. These suggested methods were evaluated by interviews with actors in the acquisition process. Four areas for LCA use in acquisition were identified: learning about environmental aspects of products; fulfilling customer requirements; setting environmental requirements; and choosing between alternatives. The interviewees were interested in using LCA, but there is a need for an initiative by one or several actors if the method is to be used regularly and the results must be communicated within the organisations involved in procurement. Environmental consideration should be taken early in the acquisition process and environmental matters integrated into other activities of the organisations involved. Environmental costs are not explicitly considered in the LCCs used by the interviewees today, but internal environmental costs should be included. Costs likely to be internal can also be included. / QC 20100616
123

Life Cycle Thinking and Waste Policy : Between Science and Society

Lazarevic, David January 2012 (has links)
This study investigates the application of life cycle thinking (LCT) and life cycle assessment (LCA) in the field of waste management from perspectives based in the social sciences. LCT is explored through the theoretical construct of regimes, drawing theoretical resources from a combination of the ‘pragmatic turn’, the economics of conventions and transition theory.This work is based on eight papers treating theoretical arguments, qualitative and quantitative analysis, case studies and semi-structured interview data. LCT is placed in the context of contemporary societies. LCA is seen as an instrument of quantification and evaluation used by actors which have both similar and disparate objectives, and who offer justifications for its use through arguments embedded in conflicting pluralities of worth. Furthermore, this work analyses LCA as a tool for the qualification of the waste hierarchy; a waste management principle articulating a convention based on closed material cycles. This study argues that the technological trajectory of waste management regimes has been significantly influenced, inter alia, by actors’ institutional articulation of the waste hierarchy at national and territorial levels. It discusses the legitimacy of LCA, and the quantitative application of LCT, as an intermediary object used to qualify the waste hierarchy. Furthermore, LCT is placed in a prospective context which may be used to assist in the transition toward sustainable waste management. / <p>QC 20121127</p>
124

Integrated environmental assessment methods as a tool for sustainable design : some case studies

Strömberg, Larissa January 2005 (has links)
QC 20100930
125

Industrial cleaning with Qlean Water : a case study of printed circuit boards

Lindahl, Mattias, Svensson, Niclas, Svensson, Bo, Sundin, Erik January 2013 (has links)
Many manufacturing companies are looking for ways to substitute environmentally problematic cleaning methods for surface treatments with more environmentally friendly ones. In this paper, one potential solution is described. The Qlean method, based on cleaning with highly pure water (in this paper defined as Qlean Water), is a novel cleaning method. This method, now utilized at one plant at a leading major international electronic company, has substituted previous chemical-based methods for cleaning printed circuit boards prior to lacquering. This paper presents, based on that company's primary data, a comparative study using environmental analysis and economic life cycle cost review between cleaning with Qlean Water and conventional cleaning. The focus is on the environmental and economic performance of the two alternatives. The conclusion is that Qlean Water offers both a significant economic and environmental cost reduction and a better product. This is the case even though all identified economic benefits derived from using Qlean Water, e.g. that the quality and technical lifetime have been extended for the printed circuit boards with the Qlean Water cleaning method, are not considered in the economic analysis.
126

Assessing the Social Performance of Products: Developing a Set of Indicators for Vattenfall AB Connected to the International EPD® system

Welling, Sebastian January 2013 (has links)
A set of indicators has been developed by the author of this work to assess the social performance of Vattenfall’s products (electricity &amp; heat). This set of indicators has been adapted to the requirements of the International EPD® system. The aim has been to create a set of indicators that can be applied to all processes within the lifecycle. The indicators are supposed to make a best possible statement of the social performance of a companies’ product, including the most relevant issues and topics within the pillar of social science and social sustainability. The method used for the development of the indicators is the Delphi method. The Delphi process includes several rounds of reviewing. A group of experts usually carries out the reviewing. In this study five rounds of reviewing has been conducted with the help of nine experts. The first round has been an extensive literature review. The 390 indicators found in the literature have been classified according to the system and the instruction of S-LCA, which are described in the Guidelines for Social Life Cycle Assessment of Products. The fifth round of reviewing has been the last one and consensus on the list of indicators could be reached. The outcome of the development process has been a set of 30 indicators. Not all subcategories proposed in UNEP/SETAC’s Guidelines for Social Life Cycle Assessment of Products have been covered. The indicators have been distinguished into two categories: core and additional. Some important social issues could not be expressed in the form of an indicator. They have been added in the final outcome of the paper, the ‘socioprofile’, as additional information. The measurement and impact assessment of qualitative indicators have been a major challenge of this study. Data availability can be seen as another critical field of the study and the application of the indicators. Other studies that have been conducted focused on a lower amount of indicators. The study has shown the possibility to quantify and measure social impacts to a certain degree. The proposed indicators are aiming at a globally focused assessment of social sustainability. The inclusion of experts and the group discussions with those experts have shown the importance of these indicators. The next step in the development of social sustainability indicators is the implementation of these indicators in a practical application and the study of the outcome. To be applicable within the International EPD® system, the Product Category Rules also have to be updated to allow for a Sustainable Product Declaration.
127

Eco-design implementation for complex industrial system : From scenario-based LCA to the definition of an eco-innovative R&D projects portfolio

Cluzel, François 27 September 2012 (has links) (PDF)
Face to the growing awareness of environmental concerns issued from human activities, eco-design aims at offering a satisfying answer in the products and services development field. However when the considered products become complex industrial systems, there is a lack of adapted methodologies and tools. These systems are among others characterised by a large number of components and subsystems, an extremely long and uncertain life cycle, or complex interactions with their geographical and industrial environment. This change of scale actually brings different constraints, as well in the evaluation of environmental impacts generated all along the system life cycle (data management and quality, detail level according to available resources...) as in the identification of adapted answers (management of multidisciplinary aspects and available resources, players training, inclusion in an upstream R&D context...). So this dissertation aims at developing a methodology to implement ecodesign of complex industrial systems. A general methodology is first proposed, based on a DMAIC process (Define, Measure, Analyse, Improve, Control). This methodology allows defining in a structured way the framework (objectives, resources, perimeter, phasing...) and rigorously supporting the ecodesign approach applied on the system. A first step of environmental evaluation based on Life-Cycle Assessment (LCA) is thus performed at a high systemic level. Given the complexity of the system life cycle as well as the exploitation variability that may exist from one site to another, a scenario-based approach is proposed to quickly consider the space of possible environmental impacts. Scenarios of exploitation are defined thanks to the SRI (Stanford Research Institute) matrix and they include numerous elements that are rarely considered in LCA, like preventive and corrective maintenance, subsystems upgrading or lifetime modulation according to the economic context. At the conclusion of this LCA the main impacting elements of the system life cycle are known and they permit to initiate the second step of the eco-design approach centred on environmental improvement. A multidisciplinary working group perform a creativity session centred on the eco-design strategy wheel (or Brezet wheel), a resource-efficient eco-innovation tool that requires only a basic environmental knowledge. Ideas generated during creativity are then analysed through three successive filters allowing: (1) to pre-select and to refine the best projects; (2) to build a R&D projects portfolio thanks to a multi-criteria approach assessing not only their environmental performance, but also their technical, economic and customers' value creation performance; (3) to control the portfolio balance according to the company strategy and the projects diversity (short/middle/long term aspect, systemic level...). All this work was applied and validated at Alstom Grid on electrical conversion substations used in the primary aluminium industry. The methodology deployment has allowed initiating a robust eco-design approach recognized by the company and finally generating a portfolio composed of 9 eco-innovative R&D projects that will be started in the coming months.
128

Life Cycle Assessment In Ferrous Foundry Industry

Yigit, Cisem 01 February 2013 (has links) (PDF)
Foundries are most widely facilities all around the world, producing high amounts of castings. In this study, environmental impact of metal foundries was investigated toward a life cycle assessment (LCA) goal. Studies were conducted in two foundry plants in order to collect the inventory data. The difference between the plants regarding their processes was the application of secondary sand reclamation (SSR) in Plant 2. Application of SSR is indicated as a
129

Environmental impact assessment and optimisation of commercial aviation

Howe, Stuart 11 1900 (has links)
The aviation industry represents approximately 3% of global greenhouse gas emissions, however with significant growth expected over the coming decades this proportion is expected to increase. Continued governmental and social pressure to reduce global emissions is posing a challenging question to the industry; how to improve environmental efficiency and reduce emissions with increasing industry growth. The environmental impact of aviation globally is discussed, examining the significant emissions and protocols that exist and their relative impacts both environmentally and economically. The viability of alternative biofuels is discussed, determining the life cycle environmental impact of future replacements to kerosene based jet fuel. This thesis therefore aims to provide an understanding of the fundamentals of aviation emissions but also most importantly provide possible solutions to assist the industry in reducing its emissions ‘footprint’. An important factor in determining efficiency improvements is to understand the impact of particular stages of an aircraft life and the impact they have individually. This was achieved using an established methodology called Life Cycle Assessment (LCA), which is an efficient tool for the analytical consideration of the environmental impact of manufacturing, operation and decommissioning. The results of a comprehensive LCA study of an Airbus A320 are documented considering all phases of the service life. The study draws useful conclusions, indicating the significance of special materials such as carbon fibre reinforced plastic (CFRP) on the total manufacturing emissions of the aircraft and indicating its operational phase as the one contributing most in its environmental performance breakdown. The thesis also examines short-term efficiencies for emissions reduction in commercial aviation, focussing on improvements in aircraft routing. The initiation of the EU emissions trading system (ETS) within European aviation willincentivise airlines to reduce their annual CO2 emissions. An alternative routing strategy is proposed for selected long haul routes, which introduces multiple stages into the route utilising two aircraft and is shown to reduce total CO2 emissions by up to 13.7%. Combined with blended biofuel, this reduction was estimated to increase to 16.6% with a reduction in ticket fares estimated to be as high as $19 per passenger per flight.
130

Life Cycle Assessment as a Tool for Green Chemistry: Application to Different Advanced Oxidation Processes for Wastewater Treatment

Muñoz Ortiz, Ivan 05 May 2006 (has links)
El objetivo de la tesis es contribuir a la aceptación del Análisis de Ciclo de Vida (ACV) como herramienta metodológica para la evaluación medioambiental de procesos químicos diseñados siguiendo las pautas de la Química Verde. Se pretende asimismo complementar e integrar la evaluación ambiental con la correspondiente evaluación económica, también desde una perspectiva de ciclo de vida. Con el objetivo de mostrar la potencial utilidad del ACV en este ámbito, se llevan a cabo dos casos de estudio en los cuales se evalúan diferentes Procesos Avanzados de Oxidación (PAOs) para el tratamiento de aguas residuales de la industria conteniendo contaminantes orgánicos persistentes. Las tecnologías evaluadas son: fotocatálisis en fase heterogénea, fotocatálisis en fase homogénea mediante procesos foto-Fenton, y ozonización. El primer caso de estudio se lleva a cabo a partir de datos a escala de laboratorio, mientras que el segundo caso de estudio, de carácter más detallado, se lleva a cabo mediante datos de planta piloto e industrial. Ambos estudios complementan la dimensión ambiental con la dimensión económica, utilizando la herramienta Coste del Ciclo de Vida (CCV). A continuación, se lleva a cabo una discusión sobre la utilidad del ACV en el ámbito de los procesos químicos, dependiendo de la escala de análisis: desde el laboratorio hasta la aplicación comercial. Finalmente, se presentan las conclusiones globales de la tesis, que pueden resumirse del siguiente modo:- La cuantificación de los avances alcanzados mediante la aplicación de los principios de la Química Verde requiere herramientas, habiéndose mostrado la potencial utilidad del ACV en este ámbito mediante dos casos de estudio sobre PAOs.- Se ha mostrado la posibilidad de aplicar el ACV tanto al nivel más básico de la Química Verde (laboratorio) hasta el más avanzado (aplicación comercial). Sin embargo los resultados obtenidos mediante ACVs basados en datos de laboratorio no necesariamente coinciden con los obtenidos en un estudio detallado, debido a: 1) falta de optimización de los procesos en laboratorio y 2) exclusión de procesos o fases del ciclo de vida que pueden ser relevantes, debido a la falta de datos. Por ello, tales estudios deben ser utilizados únicamente como evaluaciones preliminares.- El ACV despliega su potencialidad en estudios detallados, utilizando datos originados a escala piloto o industrial. Asimismo, el CCV se presenta como un complemento muy apropiado para el ACV, principalmente también en el caso de estudios detallados. / The goal of the thesis is to contribute to the acceptance of Life Cycle Assessment (LCA) as a methodological tool for environmental evaluation of chemical processes designed by following the guidelines of Green Chemistry. This work also intends to complement and to integrate in the same framework the environmental assessment with the respective economic assessment, taking into account a life cycle perspective as well. In order to demonstrate the potential suitability of the LCA tool in this context, two case studies are carried out on the subject of Advanced Oxidation Processes (AOPs) for treating industrial wastewaters containing persistent organic pollutants. In particular, the evaluated AOP technologies are: heterogeneous photocatalysis, homogeneous photo-Fenton, and ozonation. The first case study is carried out by exclusively using data derived from laboratory experiments, while the second case study is more detailed, and carried out by using data from pilot plants and industrial plants. Both studies include, along with the environmental assessment, the corresponding economic assessment, based on Life Cycle Costing (LCC). Following these studies, a discussion is made on the suitability of LCA in the context of chemical processes depending on the scale of analysis. Finally, the overall conclusions of the thesis are outlined, which can be summarised as follows:- In order to assess the advances derived from applying Green Chemistry principles in the design of chemicals and chemical processes, methodological tools are needed. This thesis supports that LCA can be used for such a purpose, as has been shown by means of two case studies on AOPs.- Application of LCA can be carried out at several stages: from the most basic, namely the laboratory scale, to the most advanced, namely commercial application. However, results obtained by means LCA studies based exclusively on laboratory-derived data do not necessarily match the results obtained in a detailed LCAs, mainly due to: 1) lack of optimization of the conditions in which the chemical process takes place in laboratory tests, and 2) excluding relevant operations or life cycle phases which are hardly quantifiable when evaluated from laboratory tests. For this reason, it is suggested that laboratory-derived LCAs should be used only as a means of obtaining preliminary environmental information.- The potential of LCA as a tool is displayed when detailed studies, based on large-scale application data, are carried out. The LCC tool, on the other hand, presents itself as a very suitable complement, mainly when performing detailed studies.

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