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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.
31

Measuring and Characterizing the Ecological Footprint and Life Cycle Environmental Costs of Antarctic Krill (Euphausia superba) Products

Parker, Robert 11 April 2011 (has links)
The fishery for Antarctic krill (Euphausia superba) has received considerable attention in recent years, owing largely to the possibility of its significant expansion and the ecological implications of increased extraction of a keystone species. This thesis employed Ecological Footprint (EF) analysis and life cycle assessment (LCA) to measure the resource use, energy use, and emissions associated with three krill-derived products: meal and oil for aquaculture feeds, and omega-3 krill oil capsules for the nutraceutical market. The product supply chains of one krill fishing and processing company, Aker BioMarine, were used as a case study to examine Antarctic krill-derived products. Antarctic krill products were compared to products from similar fisheries targeting other species for reduction into meal and oil, including Peruvian anchovy (Engraulis ringens), Atlantic herring (Clupea harengus), blue whiting (Micromesistius poutassou) and Gulf menhaden (Brevoortia patronus), on the basis of marine footprint, carbon footprint, and fuel use intensity.
32

Environmental and Performance Analysis of a 5kW Horizontal Axis Wind Turbine in East Central Alberta

Rooke, Braden Unknown Date
No description available.
33

Bio-oil Transportation by Pipeline

Pootakham, Thanyakarn Unknown Date
No description available.
34

Material flows in the waterjet industry : an environmental perspective

Abbatelli, Daniele January 2014 (has links)
Abrasive Waterjet cutting (AWJ) presents many advantages over competing machining techniques, but several issues are related to the high volume of materials (and in particular of abrasive) used in the process. In this study, the environmental impact of the material flows in the abrasive waterjet industry has been analyzed adopting a life cycle perspective in order to individuate which phases place the largest burden on the environment. Moreover, three alternative abrasives (crushed rock, recycled glass and synthetic abrasive) and three disposal practices (in-site recycling, off-site recycling and recycling as construction material) have been also evaluated to estimate the benefits that can be achieved if these could be used in place of garnet abrasives and landfilling. The transportation of the abrasive resulted to be the phase that has the largest influence in every case and thus should be reduced as much as possible. For what concerns the alternative options, the usage of recycled glass and the in-site recycling of the abrasive were the two alternatives with the best environmental performances. However, crushed rock could be the best option for what concerns the global warming potential if carbon sequestration due to carbonation of silicate rocks is taken into account. Off-site recycling and recycling as construction material are good options only if the transportation to the recycling site can be reduced. Synthetic abrasive are instead found to have a much larger impact compared to every other alternative examined.
35

Bio-oil Transportation by Pipeline

Pootakham, Thanyakarn 11 1900 (has links)
Bio-oil which is produced by fast pyrolysis of biomass has high energy density compared to as received biomass. Two cases are studied for pipeline transport of bio-oil, a coal-based and hydro power based electricity supplies. These cases of pipeline transport are compared to two cases of truck transport (trailer and super B-train truck). The life cycle GHG emissions from the pipeline transport of bio-oil for the two sources of electricity are 345 and 17 g of CO2 m-3 km-1. The emissions for transport by trailer and super B-train truck are 89 and 60 g of CO2 m-3 km-1. Energy input for bio-oil transport is 3.95 MJ m-3 km-1 by pipeline, 2.59 MJ m-3 km-1 by trailer, and 1.66 MJ m-3 km-1 by super B-train truck. The results show that GHG emissions in pipeline transport are largely dependent on the source of electricity; substituting 250 m3 day-1 of pipeline-transported bio-oil for coal can mitigate about 5.1 million tonnes of CO2 per year in the production of electricity. The fixed and variable components of cost are 0.0423 $/m3 and 0.1201 $/m3/km at a pipeline capacity of 560 m3/day and for a distance of 100. It costs less to transport bio-oil by pipeline than by trailer and super B-train tank trucks at pipeline capacities of 1,000 and 1,700 m3/day, and for a transportation distance of 100 km. Power from pipeline-transported bio-oil is expensive than power that is produced by direct combustion of wood chips and transmitted through electric lines.
36

Comparative life cycle assessment of rice husk utilization in Thailand

Prasara-A, Jittima, s3126806@student.rmit.edu.au January 2010 (has links)
Thailand is one of the largest rice producing nations in the world. Moreover, there is a trend for Thai rice exports to increase. This could imply that if the trend continues, there will be an increased quantity of rice husk in the future. Rice husk is a co-product of rice products generated in the rice milling process, accounting for about 23 percent of the total paddy weight. To make use of this large quantity of rice husk, the husk has traditionally been used as an energy source in the rice mills themselves. More recently, the Thai government has promoted the use of biomass to substitute for fossil fuel consumption and to reduce the environmental impacts caused by using fossil fuels. Therefore, rice husk, which is one of the main sources of biomass in Thailand, has already been used on a commercial scale. However, the environmental impacts associated with different rice husk applications have not yet been widely investigated in the Thai context. While there is a need to find ways of dealing with rice husk disposal, it is also important to ensure that this husk is used in ways that harm the environment least. This research aims to identify the most environmentally friendly use of rice husk for Thailand. To achieve this, the research is divided into three main stages; identification of main current and potential uses of rice husk in Thailand; data collection; and data analysis using Life Cycle Analysis approach. A range of methods such as literature review, questionnaires with rice mill owners, and interviews with industry personnel, were used to help in identifying the current and potential uses of rice husk. The major current and potential rice husk uses chosen to be examined in this research are those uses of rice husk in electricity generation, in cement manufacture and in cellulosic ethanol production. The second stage is to collect detailed data about the processes of the selected rice husk uses to be examined. This was undertaken by literature review, questionnaires and interviews with involved industry personnel. The last stage is to analyse the data collated. Life Cycle Assessment (LCA) approach and the L CA software package SimaPro (version 7.1.6) were used to assess the environmental impacts of the selected rice husk uses. Results from the LCA are reviewed in the context of critical policy issues, including the Thai government biomass policies; the capacity of the production process of rice husk use options; and the infrastructure availability and practicality of the rice husk use options. Based on the goal and scope of the study, the data available for this study and the review of the issues just mentioned, it is concluded that, in the short term, the most practical environmentally friendly use of rice husk across the three uses investigated is the use of rice husk in electricity generation. However, with expected oil shortages in the future, rice husk should also be considered for use in cellulosic ethanol production, as this option helps to save some amount of petrol.
37

Integrated environmental assessment of industrial products

Sun, Mingbo, Mechanical & Manufacturing Engineering, Faculty of Engineering, UNSW January 2004 (has links)
Life Cycle Assessment (LCA) has been successfully used as an environmental assessment tool for the development of ecologically sustainable products. The application of LCA in the early design stage has been constrained by the requirement of large amounts of data and time for carrying out the assessment. In addition, the complexity of LCA causes further difficulties for product developers. In order to integrate the environmental assessment into the process of product development, this research proposes an integrated decision model for sustainable product development and a simplified LCA approach for the application in the early stage of product design. The main advantage of the proposed model is that it incorporates the environmental aspects of product development into the existing product development framework. It enables designers to strike a balance between the product???s environmental performance and other traditional design objectives. The simplified LCA approach is based on the concept and application of Environmental Impact Drivers. Material-based environmental impacts and Energy-based environmental impacts are used to predict the total environmental impact of a product. Two sets of impact drivers were developed accordingly. The Material-based Impact Drivers were identified by classifying materials into 16 groups according to the nature of the materials and their environmental performance. Energy-based Impact Drivers were developed for various energy sources in major industrial regions. Product LCA cases were used to verify the proposed methods. The results computed by the application of the impact drivers were compared with the results of full LCA studies. It is concluded that with the proposed approach, the product???s environmental performance can be assessed in a very short time and with very basic data input requirements and acceptable accuracy.
38

Integrated environmental assessment of industrial products /

Sun, Mingbo. January 2004 (has links)
Thesis (Ph. D.)--University of New South Wales, 2004. / Also available online.
39

Avaliação da sustentabilidade do biodiesel da soja no Rio Grande do Sul : uma abordagem de ciclo de vida

Zortea, Rafael Batista January 2015 (has links)
A condição para o ser humano continuar usufruindo dos recursos naturais de forma sustentável para o planeta passa, obrigatoriamente, por uma revisão do seu modo de vida atual. Além disso, ao se repensar este novo estilo de convivência com o resto do planeta, o homem deve avaliar os prováveis efeitos que tais mudanças poderão gerar.Assim, torna-se importante analisar quais externalidades (positivas ou negativas) acabam resultando neste processo de mudança. Entre as formas de análise existentes para os impactos gerados por um novo produto, processo ou serviço,encontra-se a Avaliação do Ciclo de Vida (ACV). Este método tem como objetivo compreender e lidar com tais impactos gerados tanto de forma qualitativa, como também de forma quantitativa. A ACV busca verificar tais impactos em todas as suas fases do ciclo de vida, ou seja, desde a extração das matérias-primas, passando pelo processo de fabricação e uso até o descarte ou descaracterização final de um determinado produto. Porém, tais impactos não se restringem apenas ao campo ambiental. Ao se questionar a sustentabilidade do modo de vida do ser humano, tal escopo acaba se ampliando, incluindo também as questões social e econômica. Desta forma, avaliações que atualmente analisam somente os impactos ambientais num processo de fabricação, por exemplo, terão que se auxiliar de mensurações econômicas e sociais a fim de poder compreender e lidar com a futura sustentabilidade deste processo. O mesmo acaba valendo para a metodologia adotada, pois a análise dos impactos ambientais terá que englobar os resultados econômicos e sociais. É neste caminhar que a Avaliação do Ciclo de Vida busca se adequar a esta visão de avaliação baseada nestas três dimensões (ambiental, econômica e social) tornando-seuma Avaliação da Sustentabilidade do Ciclo de Vida (ASCV). Este novo método buscou agregar os impactos sociais e econômicos com os ambientais já medidos durante o ciclo de vida de um determinado produto ou serviço. O Rio Grande do Sul (RS), assim como todo o Brasil vem enfrentando este mesmo desafio, a partir da homologação da Lei no 11.097, que determina a adição de biodiesel ao óleo Diesel. Desta forma, a matriz energética brasileira começou a se modificar incorporando fontes de energia alternativas através da biomassa, entre elas a soja. Portanto, torna-se prudente avaliar de que forma os impactos ambientais, sociais e econômicos se comportam ao se substituir o Diesel pelo biodiesel. Assim, este trabalho buscou verificar dentro do estado do Rio Grande do Sul o nível de sustentabilidade do biodiesel de sojabaseando-se no ciclo de vida deste. Para isso,foi utilizada uma forma de ASCV a fim de qualificar e quantificar estes impactos. Tais resultados têm o intuito de auxiliar nesta nova escolha para a matriz energética, para que os futuros tomadores de decisão possam lidar melhor com este processo de transição. Desta maneira trabalhou-se o ciclo de vida do biodiesel gaúcho em três fases: agrícola, industrial e uso e transporte. Foram mensuradas 6 categorias de impacto ambiental, 3 categorias de custo e 3 partes interessadas: acidificação, eutrofização, aquecimento global, recursos abióticos, uso do solo, uso da água, custos de insumos, custos de infraestrutura e manutenção, despesas financeiras, trabalhadores, comunidade local e sociedade, e atores da cadeia de valor. A coleta de dados ocorreu tanto por questionários como por coleta de dados secundários (específicos e genéricos). De uma forma geral verificou-se que enquanto a fase agrícola do biodiesel gaúcho destaca-se na dimensão ambiental, a fase industrial apresenta potencialidades na dimensão econômica. Verificou-se que os impactos mais críticos em cada dimensão do ciclo de vida do biodiesel acabaram sendo a acidificação (ambiental), custos de insumos (econômica) e a parte interessada comunidade local/sociedade (social). Por fim,verificou-se que o biodiesel gaúcho possui uma boa sustentabilidade onde se percebe a dimensão social com maior potencialidade de melhoria. / The condition of human being using natural resources in a way to become sustainable to the planet necessitates revision in our current way of life. Besides that, when human beings think about a new coexistence with the rest of the planet, they must evaluate the probable effects (that) their actions can generate. Hence, it is important to analyze which externalities (positive or negative) may result from this process. Among the methods which already exist to evaluate the impacts generated by a new product, process or service; there is the Life Cycle Assessment (LCA). This method aims to understand and deal with the impacts generated, in both quantitative and qualitative ways. LCA seeks to verify the impacts in all phases, i.e., from the raw material extraction through the manufacturing process and use, until disposal as waste. However, these impacts are not restricted only to the environmental field. When the humans way of life is questioned, in terms of sustainability, it is necessary to widen the scope, aggregating also the social and economic dimensions. Therefore, current evaluations which analyze only environmental impacts in the manufacturing process, for instance, are being expanded for economical and social measurements in order to understand and deal with the sustainability of these processes. The same happens with methods, because the environmental impact analysis will have to encompass social and economic results. These include the LCA method which we should try to fit in this kind of evaluation based on three dimensions (environmental, social and economical), offering a Life Cycle Sustainability Assessment (LCSA). This innovative method seeks to aggregate the social and economical impacts into the environmental impacts already measured during the LCA related to a specific product or service. Rio Grande do Sul State (RS), like the rest of Brazil, has this same challenge, since the approval of the Brazilian Law number 11.097 which has established biodiesel addition to Diesel. In this way, Brazilian energy matrix began to change; encompassing alternative energy sources from biomass, among them soybean. Therefore, with a cautious approach it becomes necessary to evaluate in which way environmental, social and economical impacts behave when Diesel is replaced by soybean biodiesel. Thus, this work seeks to verify, the level of sustainability of soybean biodiesel in produced in Rio Grande do Sul, based on their LCA. For this, it will be used an LCSA analysis with the aim to qualify and quantify these impacts. The results obtained will help in a better understanding of this energy matrix, assisting decision-makers to better deal with this transition process. In this way, the life cycle of Rio Grande do Sul biodiesel was assessed in three stages: agricultural, industrial, and use and transport. It was measured 12 impact categories and/or stakeholders: acidification, eutrophication, global warming, abiotic depletion, land use, water depletion, supply costs, infrastructure and maintenance costs, financial expenses, workers, local communities and society, and value chain actors. The data collection was made both, by questionnaires and by secondary data collect (specific and generics). In general, it was verified that while the agricultural stage of the biodiesel stand out in environmental dimension, the industrial stage presents potential in economical dimension. Besides that, the stage of use and transport presented like the weakest link in this biofuel chain. In relation to social dimension was perceived a lack of maturity in all stages of life cycle which brought problemsto a better data collection and homogeneity of these results in relation to environmental and economical dimension results. It was found that the most critical impacts in each dimension were acidification (environmental), supply costs (economical) and the stakeholder local communities/society (social). Lastly, it was checked that the Rio Grande do Sul biodiesel has a good level of sustainability which it is possible to perceive a social dimension with higher potential of improvement.
40

Addressment of Uncertainty and Variability in Attributional Environmental Life Cycle Assessment

January 2016 (has links)
abstract: 'Attributional' Life Cycle Assessment (LCA) quantitatively tracks the potential environmental impacts of international value chains, in retrospective, while ensuring that burden shifting is avoided. Despite the growing popularity of LCA as a decision-support tool, there are numerous concerns relating to uncertainty and variability in LCA that affects its reliability and credibility. It is pertinent that some part of future research in LCA be guided towards increasing reliability and credibility for decision-making, while utilizing the LCA framework established by ISO 14040. In this dissertation, I have synthesized the present state of knowledge and application of uncertainty and variability in ‘attributional’ LCA, and contribute to its quantitative assessment. Firstly, the present state of addressment of uncertainty and variability in LCA is consolidated and reviewed. It is evident that sources of uncertainty and variability exist in the following areas: ISO standards, supplementary guides, software tools, life cycle inventory (LCI) databases, all four methodological phases of LCA, and use of LCA information. One source of uncertainty and variability, each, is identified, selected, quantified, and its implications discussed. The use of surrogate LCI data in lieu of missing dataset(s) or data-gaps is a source of uncertainty. Despite the widespread use of surrogate data, there has been no effort to (1) establish any form of guidance for the appropriate selection of surrogate data and, (2) estimate the uncertainty associated with the choice and use of surrogate data. A formal expert elicitation-based methodology to select the most appropriate surrogates and to quantify the associated uncertainty was proposed and implemented. Product-evolution in a non-uniform manner is a source of temporal variability that is presently not considered in LCA modeling. The resulting use of outdated LCA information will lead to misguided decisions affecting the issue at concern and eventually the environment. In order to demonstrate product-evolution within the scope of ISO 14044, and given that variability cannot be reduced, the sources of product-evolution were identified, generalized, analyzed and their implications (individual and coupled) on LCA results are quantified. Finally, recommendations were provided for the advancement of robustness of 'attributional' LCA, with respect to uncertainty and variability. / Dissertation/Thesis / Doctoral Dissertation Sustainability 2016

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