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Böttger, Henning M. "Modelling the water cycle on Mars." Thesis, University of Oxford, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.289340.
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Shwageraus, Evgeni 1973. "Rethinking the light water reactor fuel cycle." Thesis, Massachusetts Institute of Technology, 2003. http://hdl.handle.net/1721.1/16641.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Nuclear Engineering, February 2004.Includes bibliographical references (p. 249-262).
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
The once through nuclear fuel cycle adopted by the majority of countries with operating commercial power reactors imposes a number of concerns. The radioactive waste created in the once through nuclear fuel cycle has to be isolated from the environment for thousands of years. In addition, plutonium and other actinides, after the decay of fission products, could become targets for weapon proliferators. Furthermore, only a small fraction of the energy potential in the fuel is being used. All these concerns can be addressed if a closed fuel cycle strategy is considered offering the possibility for partitioning and transmutation of long lived radioactive waste, enhanced proliferation resistance, and improved utilization of natural resources. It is generally believed that dedicated advanced reactor systems have to be designed in order to perform the task of nuclear waste transmutation effectively. The development and deployment of such innovative systems is technically and economically challenging. In this thesis, a possibility of constraining the generation of long lived radioactive waste through multi-recycling of Trans-uranic actinides (TRU) in existing Light Water Reactors (LWR has been studied. Thorium based and fertile free fuels (FFF) were analyzed as the most attractive candidates for TRU burning in LWRs. Although both fuel types can destroy TRU at comparable rates (about 1150 kg/GWe-Year in FFF and up to 900 kg/GWe-Year in Th) and achieve comparable fractional TRU burnup (close to 50a/o), the Th fuel requires significantly higher neutron moderation than practically feasible in a typical LWR lattice to achieve such performance.
(cont.) On the other hand, the FFF exhibits nearly optimal TRU destruction performance in a typical LWR fuel lattice geometry. Increased TRU presence in LWR core leads to neutron spectrum hardening, which results in reduced control materials reactivity worth. The magnitude of this reduction is directly related to the amount of TRU in the core. A potential for positive void reactivity feedback limits the maximum TRU loading. Th and conventional mixed oxide (MOX) fuels require higher than FFF TRU loading to sustain a standard 18 fuel cycle length due to neutron captures in Th232 and U238 respectively. Therefore, TRU containing Th and U cores have lower control materials worth and greater potential for a positive void coefficient than FFF core. However, the significantly reduced fuel Doppler coefficient of the fully FFF loaded core and the lower delayed neutron fraction lead to questions about the FFF performance in reactivity initiated accidents. The Combined Non-Fertile and UO2 (CONFU) assembly concept is proposed for multi- recycling of TRU in existing PWRs. The assembly assumes a heterogeneous structure where about 20% of the UO2 fuel pins on the assembly periphery are replaced with FFF pins hosting TRU generated in the previous cycle. The possibility of achieving zero TRU net is demonstrated. The concept takes advantage of superior TRU destruction performance in FFF allowing minimization of TRU inventory. At the same time, the core physics is still dominated by UO2 fuel allowing maintenance of core safety and control characteristics comparable to all-UO2.
by Evgeni Shwageraus.
Ph.D.
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Pradinaud, Charlotte. "Considering water quality and characterizing water as a resource in Life Cycle Assessment." Thesis, Montpellier, SupAgro, 2018. http://www.theses.fr/2018NSAM0012.
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Maintenir la qualité des ressources en eau est l'un des défis majeurs auxquels la société d’aujourd’hui doit faire face. Il est donc primordial que ce critère soit intégré correctement dans les méthodes d’analyse d’impacts environnementaux, tel que l’Analyse du Cycle de Vie (ACV). Cependant, l’estimation de la qualité de l’eau et la manière dont cette information est utilisée dans les modèles d’évaluation d’impacts soulève un certain nombre de challenges méthodologiques, d’où la problématique de recherche : « Comment considérer la qualité de l’eau dans l’évaluation des impacts de l’utilisation de l’eau en ACV, de l’inventaire aux Aires de Protection ? ». Ce travail de thèse propose dans un premier temps une étude approfondie du rôle et de la nécessité de l’information « qualité de l’eau » dans l’évaluation des impacts de plusieurs type d’utilisation d’eau (usage consommatif, dégradatif et amélioration de la qualité). Cette étude s’applique aux différentes chaines de causalité de manière mécanistique, jusqu’aux trois Aires de Protection (AoP) santé humaine, qualité des écosystèmes et ressources naturelles. Afin d’améliorer la compréhension et la considération des impacts de l’utilisation de l’eau sur l’AoP ressources naturelles, un cadre théorique consensuel élaboré en collaboration avec WULCA (le groupe Water Use in LCA, de l’UNEP-SETAC Life Cycle Initiative) est défini. Ce cadre fournit une base solide pour l’élaboration cohérente de méthodes d’analyse d’impacts, permettant d’évaluer la diminution irréversible de la disponibilité physique de l'eau douce et/ou de son degré d'utilisabilité pour les générations futures. La thèse se conclut par le développement d’un modèle de caractérisation d’impacts de la dégradation des ressources en eau causée par des émissions. Des facteurs de caractérisation sont calculés pour cinq métaux, au niveau midpoint. L’application de ces indicateurs permet d’améliorer l’interprétabilité des résultats concernant les défis futurs liés aux ressources en eau ainsi que les résultats des impacts sur la santé humaine liés aux problèmes de qualité d’eauMaintaining the quality of water resources is one of the major challenges society faces today. It is therefore essential that this criterion be properly integrated into environmental impact assessment methods, such as Life Cycle Assessment (LCA). However, the estimation of water quality and how this information is used in impact assessment models raises a number of methodological challenges; hence, the general research question is “How to consider water quality in water use impact assessment in LCA, from inventory to Areas of Protection?” This thesis first provides a detailed study about the role and necessity of "water quality" information in assessing impacts of different types of water use (consumptive and degradative use, as well as quality improvement). This study applies to the different cause-effect chains in a mechanistic way, in view of the three Areas of Protection (AoP) human health, ecosystem quality and natural resources. In order to improve the understanding and consideration of the water use impacts on the AoP natural resources, a consensual framework, developed jointly with WULCA (Water Use in LCA group of the UNEP-SETAC Life Cycle Initiative), is presented. This framework provides a solid basis for the consistent development of impact characterization models to assess the irreversible reduction in physical availability of freshwater and its quality-based usability for future generations. The thesis ends with the development of a characterization model for water resource degradation impacts caused by emissions. Characterization factors are calculated for five metals at the midpoint level. The application of these indicators improves the interpretability of LCA results regarding future water resource challenges and water-quality related impacts on human health
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Tejada, Francisco Javier. "Quantifying the life cycle water consumption of a passenger vehicle." Thesis, Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/43637.
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Various studies have pointed out the growing need to assess the availability of water sources in regions around the world as future forecasts suggest that water demands will increase significantly for agricultural, industrial and human consumption while freshwater resources are being depleted. One such emerging issue is the effect of industrial operations on said resources, specifically from automobiles. With numerous localities experiencing stresses on water availability, key stakeholders - suppliers, automakers, and vehicle end-users - need to better realize the effect vehicle manufacturing, usage, and disposal have on water resources.
While efforts to improve the overall environmental performance of vehicles have mainly concentrated on improving technologies, there has also been considerable effort devoted to characterizing the life-cycle performance of the vehicle product system. However, much of this work has focused on energy consumption and carbon emissions while few studies have examined water. The difference between water use versus water consumption were highlighted and the life-cycle water consumption of a gasoline-powered midsize vehicle were analyzed from material extraction through production, use, and final disposition/end of life. This analysis examines each of the phases to determine a carâ s water footprint using data from the EcoInvent Life Cycle Analysis database as well as data collected from literature sources. Although water use is typically metered at the factory level, water consumption (i.e., water lost through evaporation and/or incorporation into a material, part, and/or product) is much harder to quantify. As shown in this thesis, the difference can be an order of magnitude or more because much of the water that goes into the different processes is either reused, recycled, or discharged back to its original source. The use phase of a vehicle has the biggest impact on the overall vehicle water consumption, followed by material production, whereas water consumption for the end of life processing seems to be relatively insignificant. It is also shown that the impact of energy consumption as part of the total water footprint is very large when compared to the other processes given the dependence on water for energy production.
The assessment in this thesis represents a life-cycle inventory and serves as an initial benchmark as no previous study has been completed to determine the water consumption for the life of a vehicle, let alone for most other products. The impact of water consumption varies by region and locality, and a differentiation of impact would still be needed to determine whether the water consumption actually happens in water scarce regions or not.
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Trujillo, Iliana Cardenes. "Quantifying the energy consumption of the water use cycle." Thesis, University of Oxford, 2017. https://ora.ox.ac.uk/objects/uuid:df481801-cce1-4824-986c-612f4673b8eb.
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The management and delivery of water and wastewater consume significant amounts of energy, mostly in the form of electricity. With increasing populations, climate change, water quality issues and increasing energy prices, it is more important than ever to understand energy consumption patterns. Energy usually represents the largest operational cost in water utilities around the world, yet there is limited work aiming to quantify the specific relationship between water and its associated energy, and understand its implications for future decision-making. This thesis presents variousmethodological approachesto quantify and understand energy use in water infrastructure systems, as well as how to incorporate them in decision-making processes. The main hypotheses are as follows: firstly, a detailed understanding of the use of energy in water infrastructure systems can facilitate more efficient and sustainable water infrastructure systems and, secondly, that incorporating energy into planning for water and wastewater resources can help understand the impacts of decisions and establish trade-offs between actions. To test these hypotheses, the thesis presents an analytical approach to various areas. Firstly, it identifies, maps and quantifies the energy consumption patterns within a water infrastructure system. This is then used to identify inefficiencies and areas of potential energy saving. Secondly, it incorporates detailed energy costs into short and long-term water resources management and planning. Thirdly, it evaluates trade-offs between energy costs and changing effluent quality regulations in wastewater resources. The Thames River basin, in the south-east of England, is used as a case study to illustrate the approach. The results demonstrate that a systematic approach to the quantification of energy use in a water infrastructure system can identify areas of inefficiencies that can be used to make decisions with regards to infrastructure planning. For example, water systems have significant geo-spatial variations in energy consumption patterns that can be addressed specifically to reduce negative trade-offs. The results also show that incorporating detailed energy information into long-term water resources planning can alter the choices made in water supply options, by providing more complete information. Furthermore, methodologically, they show how several methodological approaches can be used to support more complete decision-making in water utilities to reduce short and long-term costs. In this particular case study, the results show that there are important differences in energy consumption by region, and significant differences in the seasonal and energy patterns of water infrastructure systems. For example, water treatment was shown to be the largest consumer of energy within the whole system, compared with pumping or wastewater treatment; but wastewater treatment energy consumption was shown to be the fastest growing over time due to changes in water quality regulatory frameworks. The results show that more stringent effluent standards could result in at least a doubling of electricity consumption and an increase of between 1.29 and 2.30 additional million tonnes of CO2 a year from treating wastewater in large works in the UK. These are projected to continue to increase if the decarbonisation of the electricity grid does not occur fast enough. Finally, the thesis also shows that daily energy consumption can be reduced by up to 18% by optimally routing water through a water network. optimization of water networks, and that a change in discount rates could change the daily operating costs by 19%, that in turn leads to a resulting different set of optimal investment options in a water supply network.
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Ruane, Alexander C. "Diurnal to annual variations in the atmospheric water cycle." Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2007. http://wwwlib.umi.com/cr/ucsd/fullcit?p3263195.
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Thesis (Ph. D.)--University of California, San Diego, 2007.Title from first page of PDF file (viewed July 10, 2007). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references (p. 146-154).
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Comer, Ruth Elizabeth. "Understanding the diurnal cycle in clouds and water vapour." Thesis, University of Reading, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.446198.
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Molyneaux, Glenn Arthur. "Resorption cycle heat pump with ammonia-water working fluid." Thesis, University of Ulster, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.326335.
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Sturm, Kristof. "Regional atmospheric modelling of the stable water istope cycle." Université Joseph Fourier (Grenoble), 2005. https://tel.archives-ouvertes.fr/tel-00010157.
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Dans un contexte de changement climatique, la connaissance des climats passés permet de mieux cerner l'évolution future du climat. Les isotopes stables de l'eau constituent un excellent proxy paléo-climatique. Les propriétés physiques des isotopes lourds de l'eau (H182 O; HDO) induisent des fractionnements isotopiques, qui dépendent de la température et du taux de distillation. Sous réserve d'une inversion bien conditionnée du signal isotopique, on peut reconstruire les variations passées du climat à partir d'archives isotopiques. Les carottes de glace andines constituent un enregistrement unique de la variabilité du climat tropical. En revanche, la complexité de la circulation atmosphérique rend plus ardue l'interprétation de leur signal isotopique. En conséquence, nous avons développé au cours de cette thèse un module traitant du fractionnement des isotopes stables de l'eau au sein du modèle de circulation régionale REMO pour application au cas de l'Amérique du Sud. Le manuscrit retrace les principales étapes de la thèse. Il s'agit de la mise en perspective du travail de thèse dans la problématique du changement climatique ; la description du modèle de circulation régionale REMOiso et de son module traitant des isotopes de l'eau ; la validation initiale de REMOiso sur l'Europe ; l'étude des variations saisonnières des précipitations, de la circulation atmosphérique régionale et du signal isotopique en Amérique du Sud ; de l'enregistrement par les isotopes stables de l'eau de la mousson sud-américaineClimate change has recently become a major concerning among scientists and the general public. A better knowledge of past climates helps forecasting the future evolution of climate. Stable water isotopes stand as an outstanding paleo-climate proxy. Physical properties of heavy stable water isotopes (H182 O; HDO) cause fractionation processes related to temperature and degree of distillation. If the isotopic signal is correctly inverted, past climate change can be inferred from isotopic archives. Andean ice-cores offer a unique records of tropical climate and its variability through time. However, the interpretation of the isotopic signal is difficult because of complex atmospheric dynamic over South America. For this purpose, we developed a module handling the stable water isotope fractionation processes within the regional circulation model REMO and applied it to South America. The manuscript outlines the major milestones of the present PhD. We first introduce the research topic in the wider scope of climate change; the description of the stable water isotope enabled regional circulation model REMOiso; an initial validation of REMOiso over Europe; an investigation of the seasonal variations of precipitation, atmospheric circulation and isotopic signal over South America; and at last the recording of the south American monsoon system (SAMS) by stable water isotope diagnostics
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Kvadsheim, Mari Hellvik. "Life Cycle Assessment of Desalinated Water for Enhanced Oil Recovery." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for elkraftteknikk, 2013. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-22780.
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Currently, fossil fuels supply 85% of the world?s energy demand. Nevertheless, we consume more than we are able to produce from new discoveries of fossil resources. As energy demand is predicted to grow rapidly over the next few decades, the need for new methods to sustain oil production emerges. By using new technology, known as enhanced oil recovery, it is possible to recover oil previously considered too tightly bound to the reservoir rock to be recovered in a profitable way. One such method is low-salinity waterflooding, where desalinated water is injected into the reservoir in order to increase the crude oil recovery. If implemented, this method could result in significant economic benefit, but little is known on the environmental impacts associated with it. In this thesis, a life cycle assessment of desalinated water for enhanced oil recovery was conducted. Reverse osmosis was chosen as desalination technology and a generic model located in the North Sea was developed based on existing literature. The results show that the operation phase is the largest contributor to environmental impacts due to the generation of power by natural gas-driven turbines on the platform. The chemical treatment process is also a significant contributor to environmental impacts, due to energy inputs and wastes from chemical manufacturing. The emissions of greenhouse gases from the system were calculated to be 151 kg of CO2 equivalents for each standard cubic meter of recovered crude oil. This is three times higher than greenhouse gas emissions from oil production without enhanced oil recovery methods, but substantially lower than emissions from oil sands production. It is recommended to implement enhanced oil recovery methods such as low-salinity waterflooding, rather than producing oil from unconventional fossil reserves such as oil sands. A sensitivity analysis was also conducted, presenting alternative scenarios for power supply, by means of electrification of the platform. The results show that electrification of a platform could offer substantial environmental benefits in terms of reduced emissions of greenhouse gases, depending on the composition of the electricity mix. However, several issues will need to be addressed before this should be implemented on a large scale, in order to ensure that it will indeed reduce global greenhouse gas emissions. The results from this thesis create a basis and a starting point for future research. The environmental impacts associated with desalination of water are deemed reliable; however, great uncertainty is linked to the required amount of water per standard cubic meter of recovered crude oil. In order to calculate the environmental impacts from one specific oil field or enhanced oil recovery project, it is necessary to quantify material and energy inputs, emissions and wastes, as well as the exact water-to-oil ratio by mapping and identifying key parameters and properties of the petroleum reservoir in question.
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Galvin, Mark Robert. "Maintenance cycle extension in advanced light water reactor plant design." Thesis, Springfield, Va. : Available from National Technical Information Service, 2001. http://handle.dtic.mil/100.2/ADA393174.
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Carvalho, Maria Paula Martins de Oliveira. "Portuguese pupils and the water cycle : understanding interrelated scientific concepts." Thesis, King's College London (University of London), 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.245388.
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Galvin, Mark Robert 1967. "Maintenance cycle extension in advanced light water reactor plant design." Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/91336.
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Thesis (Nav.E.)--Massachusetts Institute of Technology, Dept. of Ocean Engineering; and, (S.M.)--Massachusetts Institute of Technology, Dept. of Nuclear Engineering, 2001."June 2001."
Includes bibliographical references.
by Mark Robert Galvin.
Nav.E.
S.M.
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Kharazi, Amir Ahmadzadeh. "Study of a novel R718 turbocompression cycle." Diss., Connect to online resource - MSU authorized users, 2006.
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Thesis (Ph. D.)--Michigan State University. Dept. of Mechanical Engineering, 2006.Title from PDF t.p. (viewed on June 19, 2009) Includes bibliographic references (p. 84-89). Also issued in print.
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Amini, Adib. "The Sustainability of Ion Exchange Water Treatment Technology." Scholar Commons, 2017. http://scholarcommons.usf.edu/etd/6640.
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This research investigated using a life cycle environmental and economic approach to evaluate IX technology for small potable water systems, allowing for the identification and development of process and design improvements that reduce environmental impacts and costs. The main goals were to evaluate conventional IX in terms of life cycle environmental and economic sustainability, develop a method for improving designs of IX systems from a environmental and economic sustainability standpoint, evaluate potential design improvements, and make the research findings accessible to water professionals through user-friendly tools and frameworks that take into account their feedback. This research provides an understanding, from the perspective of life cycle environmental impacts and costs, of the tradeoffs between various reactor designs of IX, the effects of scale, key contributors to impact and cost, design trends that improve sustainability, and how combined cation anion exchange compares to conventional IX. Furthermore, tools were developed that can be used to identify design choices that improve sustainability of IX systems. These tools were made into a user-friendly format to better bridge the gap between research and practice.
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Joustra, Caryssa. "A Framework for Determining Building Water Cycle Resilience Using a Dynamic Water Resilience Assessment Model (WRAM)." Scholar Commons, 2015. http://scholarcommons.usf.edu/etd/5855.
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The aim of this project was to quantitatively measure the resilience of the building water cycle. In order to accomplish this goal, a framework was developed that outlines how building water resilience can be evaluated. The framework presented assumed that resilience describes the fulfillment of system functions; in this case, the system functions considered are those actualized by the building water system. A building water resilience assessment model (WRAM) was developed with the ability to simulate different building water cycles and resilience scenarios. Resilience is dependent on the type and magnitude of a disturbance. Therefore, unique disruption scenarios were developed to test the building water cycle resilience: (1) loss of municipal potable water and (2) loss of both municipal potable water and power. Under each scenario, the building water cycle was tested based on the type of building and the water management strategies utilized by the building.
The WRAM requires organization of water demand and source connections, and an explicit prioritization framework was produced based on water source and demand preferences found in literature. The framework gives priority to treated wastewater, stormwater, rainwater, condensate, reclaimed water, and potable water, respectively. The baseline prioritization may be manipulated by restricting demand-source connections, and shifting priorities was shown to affect the potential for potable water offsets as a precursor to resilience. Real building water demand profiles were developed from data collected using smart meters at four building sites (multi-residential neighborhood, commercial building, elementary school, and community center). Water source profiles were developed using hourly climate data for the region. Detailed building water demand and supply profiles were developed for the multi-residential and elementary school building sites for resilience assessment using the WRAM. Each building water profile was adapted into 9 scenarios with each subjected to the two disruption schemes for 5 different disruption durations (1 hour, 6 hours, 24 hours, 72 hours, and 168 hours) at 10 different randomized dates and time throughout the year. The result was 450 model runs for each building subjected to each disruption scheme (potable water loss or potable water and central power loss).
The relationship between resilience and sustainability was examined based on sustainable building practices accepted by the U.S. Green Building Council's (USGBC) Leadership in Environmental and Energy Design (LEED) green building rating system. Building WRAM outcomes include unique water demand and supply profiles used to describe resilience in terms of the level of service (LOS) of building water functions. Analysis of water profiles validated redundancy, diversity, capacity, alternative water, passivity, preparation, and adaptation potential indicators as gauges of the resilience of the building water cycle. Results showed that resilience correlates with alternative water building water management strategies, but high resilience values are still attainable using storage of non-renewable, non-sustainable sources. However, building water cycles utilizing alternative water maintained steadier resilience as disruption lengths increase due to the ability of sources to be replenished during disruption events.
The strongest correlation with LOS was observed for the diversity, redundancy, alternative water, and capacity indicators when scenarios utilizing only potable water were excluded from analysis. For these scenarios, correlation values were 0.56 for diversity, 0.56 for redundancy, 0.60 for capacity, and 1.00 for alternative water for the multi-residential building subjected to potable water loss; and 0.33 for diversity, 0.24 for redundancy, 0.62 for capacity, and 1.00 for alternative water for the multi-residential building subjected to both potable water and central power disruption. For elementary school scenarios that did not utilize potable water storage, correlation values were 0.67 for diversity, 0.64 for redundancy, 0.06 for capacity, and 0.89 for alternative water when subjected to disruption of potable water; and 0.67 for diversity, 0.64 for redundancy, 0.06 for capacity, and 0.80 for alternative water when subjected to disruption of potable water and central power. Passivity correlation to LOS was between 0.77 and 1.00 for all scenarios, building types, and disruption schemes. Passivity correlation with LOS was lower for potable water disruption scenarios, but higher when building water cycles lost power in addition to potable water. The average of each indicator was also calculated for each scenario for each of the five disruption durations by grouping the individual values from each of the 10 randomized disruption start dates and times. The correlation between the average capacity indicator and LOS greatly increased with this method to a range of 0.41 to 0.78 for all buildings subjected to each disruption scheme. In addition, a positive correlation between the preparation indicator and LOS (and corresponding negative correlation between the adaptation potential indicator and LOS) emerged for scenarios that do not utilize potable water storage. For disruption of potable water, the preparation correlation value was 0.94 for the multi-residential building and 0.78 for the elementary school. For disruption of potable water and central power, the preparation correlation value was 0.32 for the multi-residential building and 0.79 for the elementary school.
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Larsson, Malin. "Do Trichoptera in running water fly upstream?" Thesis, Linköpings universitet, Biologi, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-119828.
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Drift moves aquatic insects downstream, risking depopulation of upstream reaches. However, the necessity and existence of an upstream flight to compensate for drift has not been undisputed. I analysed a sample of approximately 70 000 Trichoptera from a stream in northern Sweden collected during one season in 1974. The overall flight direction was upstream. Females had a stronger upstream flight than males and species varied in both flight direction and strength of the preference. Flight direction was not affected by wind or trap type. Upstream flight varied during the season and with different larval behaviours. Upstream flight increased with the size of the imago and with the abundance in flight. A colonisation cycle might be in effect but even though upstream flight occurs, it might not be necessary to sustain populations in upstream reaches.
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Khurana, Mayank. "A Framework for Holistic Life Cycle Cost Analysis for Drinking Water Pipelines." Thesis, Virginia Tech, 2017. http://hdl.handle.net/10919/78357.
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Life Cycle Cost Analysis (LCCA) forms an important part of asset management practices and provides an informed decision support. The holistic nature of LCCA includes life cycle assessment (LCA) as an important component alongside economic life cycle cost analysis. The drinking water industry is right now lacking a reliable cost data structure which will ensure that all the utilities capture the same set of cost data. Also, models and tools currently available in the academia and industry are purely deterministic in nature and do not cater to uncertainty in the data. This study provides a framework for a holistic life cycle cost analysis tool which will help drinking water utilities to prioritize the activities and optimize the cost spending of the utility. The methodology includes the development of a cost data structure, a life cycle cost analysis and a life cycle assessment model in the form of an excel spreadsheet. The LCCA model has the capability to compare different pipe materials, installation, condition assessment, rehabilitation and replacement technologies. Whereas, LCA model can compare different pipe materials based on greenhouse gas emissions calculations. The final step of the methodology includes piloting the model with data from utility A. The analysis has been shown in the form of three case studies - comparison of two pipe materials, two pipe installation technologies and two pipe rehabilitation technologies. The case studies provide results in the form of comparison of total life cycle costs for different alternatives and hence a better alternative can be chosen.Master of Science
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De, La Motte Robin. "Liquid dynamics : the hydrosocial cycle and the radical politics of water." Thesis, University of Manchester, 2013. https://www.research.manchester.ac.uk/portal/en/theses/liquid-dynamics-the-hydrosocial-cycle-and-the-radical-politics-of-water(ab5470bc-3641-4d3a-8f49-d42c2ed2cff5).html.
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The thesis attempts to develop an understanding of the reproduction of power in the context of the water sector, in relation to public sector water provision, water privatization, and community-based alternatives to both. In pursuit of that it develops a “socio-political ecology” which combines the methodology of political ecology with the theoretical framework of historical-geographical materialism and the concept of social capital. it examines the hydrosocial cycle as a socionatural process which involves the continuous (re)construction of the socionatural water cycle through the (re)construction of “water” demand, supply and scarcity, as well as the socionatural construction of the state. The water sector in Venezuela serves as an illustrative example for how first, different forms of capital interact to reproduce a mode of power; second, that reproduction tends to produce a concentration of power; and third, how internal contradictions and external pressures can lead to changes in the mode of power. In particular, points of crisis produce new recognitions of radical contingency - the potential for the mode of power to be fundamentally altered - and thereby politicization and new forms of activism.
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Pettersen, Sindre. "Investigation on an Open Cycle Water Chiller based on Desiccant Dehumidification." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for energi- og prosessteknikk, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-19690.
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In this thesis, a novel open cycle desiccant dehumidification system is experimentally studied. The system is installed and operated at Shanghai Jiao Tong University (SJTU) as part of the Green Energy Laboratory (GEL) initiative. The system uses two-stage desiccant dehumidification as well as regenerative evaporative cooling for chilled water production. The purpose of the thesis is to evaluate the system performance during different ambient and operational conditions. The investigated system has great potential regarding the environmental aspect of HVAC system solutions. The system is more energy efficient compared to conventional air conditioning systems and uses solar thermal power provided by evacuated tube solar air collectors as the main source of energy. Therefore, this type of system can contribute in reducing the use of non-renewable energy sources.A lot of experiments have been performed from June to July 2012 during varying ambient conditions. As a first step, the necessary regeneration temperature level is established. The results show that this temperature should be in the range of 70-75˚C or higher to be able to achieve desired dehumidification effect. Then, experiments regarding the overall system performance during different ambient temperature and humidity conditions are performed and analyzed. The results show that the system excels good performance during periods of high ambient humidity and is capable of achieving average COPth and COPel around 0.8 and 5.7 respectively. The total dehumidification efficiency is approximately 58% and is proven to vary with respect to the regeneration temperature, where increasing regeneration temperature results in higher amount of moisture removed from the processed air. The solar collectors providing heat to the regeneration air has an efficiency of 47-60% depending on the available level of solar radiation intensity. During periods of low intensity it is proven that the heating system needs assistance from an auxiliary device to be able to generate a sufficient temperature level. The evaporative cooler producing chilled water is capable of providing water at a temperature below 21˚C during periods of high ambient temperature, and temperatures below 16˚C if the ambient temperature decreases. The achieved dehumidification and cooling capacity of the desiccant system makes it possible to provide qualified supply air with temperature in the range of 20-26˚C and absolute humidity below 12 g/kg. Also, an experiment with the purpose of investigating the newly installed second desiccant wheel is carried out. The system is operated with only the second wheel running and the results show that the dehumidification performance is very good when the second wheel provides the first stage dehumidification. Lastly, experiments investigating the impact of the pre-cooling heat exchanger is performed and analyzed.
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Kemp, Dian. "Technical evaluation of the copper chloride water splitting cycle / D. Kemp." Thesis, North-West University, 2011. http://hdl.handle.net/10394/6862.
Full textAbstract:
The global energy sector is facing a crisis caused by the increasing demand for energy.
Non-renewable energy sources, such as fossil fuels produce greenhouse gases that are
largely blamed for climate change. The Kyoto protocol requires industrialised nations to
reduce their collective greenhouse gas emissions. Hydrogen as an alternative fuel can
serve as a substitute.
Hydrogen production is expensive and the gas is largely derived from fossil fuels by a
process that releases large quantities of greenhouse gases. In South Africa work on
hydrogen production was first done on the Hybrid Sulphur cycle. The high operating
temperature and highly corrosive environment involved in the process makes this cycle
difficult to work with. The copper-chloride cycle has a lower operating temperature and
uses less corrosive materials, making the cycle potentially more economical.
Evaluation of the cycle started with the development of four models: the Base model,
the Canadian model (developed in Canada) the Kemp model and the Excess model.
The Kemp model has the best overall efficiency of 40.89 %, producing hydrogen at a
cost of US$4.48/kg. The model does not however provide the excess steam required for
the cycle. The Excess model which is based on the Kemp model does provide the
excess steam and produces an overall efficiency of 39 % and hydrogen at a cost of
US$4.60/kg.
The copper-chloride cycle has an improved efficiency and produces hydrogen at a lower
cost when compared to the hybrid sulphur cycle. The final conclusion of this thesis is
that the copper-chloride cycle should be investigated further and an expected capital
and operational costs estimate should be developed to obtain more accurate figures.Thesis (M.Ing. (Nuclear Engineering))--North-West University, Potchefstroom Campus, 2012.
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Landu, Landu. "Environmental life cycle assessment of water use in South Africa the Rosslyn industrial area as a case study /." Pretoria : [s.n.], 2005. http://upetd.up.ac.za/thesis/available/etd-04242006-153804.
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Decker, Mark Ryan. "IMPROVING THE HYDROLOGICAL CYCLE IN LAND SURFACE CLIMATE MODELS." Diss., The University of Arizona, 2010. http://hdl.handle.net/10150/195627.
Full textAbstract:
The hydrological components of land surface climate models have increased greatly in complexity over the past decade, from simple bucket models to multilayer models including separate and distinct soil water and ground water components. While the parameterizations included in these models have also increased in complexity, the fundamental ability of the numerical solution for the vertical movement of soil water in the Community Land Model (or other land surface models) to simply maintain the hydrostatic solution of the original partial differential equation has yet to be determined.Also, the ability of current generation reanalysis products to simulate near surface quantities as gauged by flux tower measurements has yet to be determined.This study demonstrates that the numerical solution as used in CLM3.5 cannot maintain the hydrostatic state. An alternate form of the equation, titled the Modified Richards equation is presented so that the numerical solution maintains steady statesolutions. Also, an improved and simple bottom boundary condition is derived that itself doesn't destroy hydrostatic initial conditions. The new solution is demonstrated to be as accurate as proven numerical solutions while being one to three orders more computationally efficient. The Modified Richards equation together with the new bottom boundary condition is shown to improve the ability of CLM to simulate soil water, water table depth, and near surface turbulent fluxes.Comparison with flux tower observations shows that ERA-Interim better simulates near surface temperature and wind speed than other current generation reanalysis products. Reanalysis products are able to reproduce the flux tower observations on monthly timescales, and the errors between the products and the measurements are primarily due to biases. However, at six hourly timescales the errors are not only larger but also caused primarily by a lack of correlation with the observations.
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Sprague, Nicolle Marie. "Copper in the Urban Water Cycle: Sources and Sinks, Benefits and Detriments, and Corrosion in Soft Waters." Thesis, Virginia Tech, 1999. http://hdl.handle.net/10919/42724.
Full textAbstract:
In recent years, stringent world-wide regulation of copper in drinking water, wastewater discharge and sludge has prompted utilities to carefully evaluate copper sources and sinks, benefits and detriments, and mitigation. This work compiled the individual efforts of researchers and utilities to provide a basis for holistic decision-making. Mass balances suggest that between 14-61% of copper in wastewater originates from home plumbing. Dosing of pure copper sulfate "root killer" by consumers, which is of unlikely value, accounted for up to 27% of copper inputs. Removal of copper in wastewater treatment ranged from 24-90%, suggesting a potential for optimization of these processes if desired. Finally, though utilities are pressured to reduce copper inputs at all stages of the urban water cycle, substantial benefits including human and wastewater bacteria micro-nutrition, water disinfection and algae control should not be overshadowed.
To better understand copper inputs from corrosion in soft waters, a 12 month study was executed. Free chlorine (0.7 mg/L) was determined to have minimally adverse effects on copper release at pH 9.5 but no significant effect at pH 7.0, and higher temperatures usually increased copper release. Organic matter including soluble and particulate NOM, sodium alginate, and gum xanthan, tended to worsen copper release. Their direct effects included complexation and mobilization of pre-existing copper scale as particulates. Indirect effects were also discovered, including a propensity of gum xanthan and alginate to decrease pH, increasing copper release, and also to produce a microbiologically unstable water, decreasing the dissolved oxygen necessary for fueling corrosion reactions. The range of organic matter effects could be placed within a unified conceptual framework.Master of Science
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Lindahl, Mattias, Niclas Svensson, Bo Svensson, and Erik Sundin. "Industrial cleaning with Qlean Water : a case study of printed circuit boards." Linköpings universitet, Industriell miljöteknik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-88920.
Full textAbstract:
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.
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McCaffery, Kevin A. "Isolation and Characterization of a Microorganism from Groundwater that Reduces Arsenate." Fogler Library, University of Maine, 2002. http://www.library.umaine.edu/theses/pdf/McCafferyKA2002.pdf.
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Leão, Susana. "Development of a worldwide-regionalised Water Supply mix in Life Cycle Assessment." Thesis, Montpellier, SupAgro, 2018. http://www.theses.fr/2018NSAM0011.
Full textAbstract:
Les services de distribution d’eau utilisent différentes ressources (eaux de surface et eaux souterraines), y compris une utilisation accrue de ressources alternatives (eau dessalée, eau réutilisée, transferts d'eau entre bassins) pour alimenter les différents utilisateurs (domestiques, agricoles, industriels, etc.). La combinaison de ces ressources en eau avec des technologies (incluant infrastructures, fonctionnement et énergie) donne lieu à une combinaison régionale d'approvisionnement en eau (WSmix) pour chaque utilisation spécifique. Actuellement, les bases de données existantes d'inventaire du cycle de vie (ICV) utilisées en Analyse du Cycle de Vie (ACV) ne proposent pas ce type de données relative aux WSmix régionalisées pour modéliser des processus. Ceci conduit à une représentation médiocre des systèmes d'approvisionnement en eau et des impacts environnementaux associés. Pour combler cette lacune, cette thèse développe (i) un cadre conceptuel cohérent de mix d'approvisionnement en eau (WSmix) pour la mise en oeuvre en ACV, (ii) une base de données opérationnelle incluant le mix de ressource en eau pour différents utilisateurs à l'échelle mondiale adossée à une matrice dite « technologique » associant chaque ressource à des technologies de production d'eau. Afin de tester en ACV l'opérationnalisation et l'applicabilité du mix WSmix à l'échelle mondiale et pour différents utilisateurs, le concept de WSmix est appliqué à deux exemples contrastés: un service (fourniture d’un m3 d’eau publique à la porte de l’utilisateur) et un produit global (production d’un kg maïs). Enfin, pour évaluer dans quelle mesure le WSmix sera affecté par les changements climatiques et socio-économiques, cette thèse propose le développement d'un WSmix Prospectif (P-WSmix) pour une mise en oeuvre pratique dans les études d'ACV et d'empreinte sur l'eauWater utilities draw different water sources (surface and groundwater), including increased use of alternative sources (e.g. desalinated water, reused water, inter-basin water transfers) to supply freshwater to different users (domestic, agriculture, etc.). The combination of water sources and technologies (including infrastructures and energy) results in a regional water supply mix (WSmix) for each specific use. Existing Life Cycle Inventory (LCI) databases used in Life Cycle Assessment (LCA), do not include these mixes when modelling processes, leading to a poor representation of water supply systems and related environmental impacts. To fill this gap, this thesis developes 1) consistent water supply mix (WSmix) model for implementation in LCA, 2) a first database of water source mixes for different users at a global scale and a technological matrix linking water sources to water production technologies in order to operationalize the practical implementation of the WSmix in LCA studies. In order to test the operationalization and applicability of the WSmix at worldwide scale and for different users, this theseis also describes the operationalization and application of the WSmix for two different water users worldwide with two different approaches: providing a generic service (public water supply) and producing a global product (maize production). Finally, to evaluate to what extent the WSmix will be affected by climate and socio-economic changes in the future, this thesis describes the development of a Prospective WSmix (P-WSmix) for practical implementation in LCA and water footprint studies
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Isberg, Ulrika & Karin Nilsson. "Life Cycle Assessment and Sustainability Aspects of Solvatten, a Water Cleaning Device." Thesis, KTH, Industriell ekologi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-127693.
Full textAbstract:
Solvatten is a water cleaning device for households in developing countries. As a Master Thesis forthe Master of Science in Engineering Programme at Kungliga Tekniska Högskolan a Life CycleAssessment of Solvatten has been conducted. The primary aim was to investigate the environmentalimpacts of Solvatten and compare it with two other common methods of accessing safe water;boiling and bottled water. Information has been gathered by contacting manufacturers and suppliersand analysed in the computer software SimaPro. The stand-‐alone LCA of Solvatten showed that theproduct gives almost no impact on ecosystem quality and human health. As the product mostly ismade of different plastic materials (i.e. fossil fuels), Solvatten has its highest impact in the damagecategory of resources. Hence, most of Solvatten’s environmental impact comes from the materialsand production processes of the black container and the transparent lid. The disposal phase ofSolvatten has been left out of the data analysis as there is a large uncertainty in waste scenarios ofdeveloping countries. Instead, a comparison was made between three different waste scenarios;landfill, incineration, and recycling with European standards. It is clear that recycling is the bestalternative, and Solvatten should show their corporate social responsibility by organizing this. Thecomparative studies conducted for Solvatten, boiling water with firewood and buying bottled waterindicated that due to Solvatten’s long lifetime, the environmental impact for Solvatten is lower. Alsodiscussed in the report are the economic and social aspects of Solvatten, which are a great advantagefor Solvatten since both time and money can be saved. Solvatten is concluded to be a goodalternative for accessing safe water.Solvatten är en produkt för att rena vatten i hushåll i utvecklingsländer. En livscykelanalys avSolvatten har gjorts som examensarbete för civilingenjörsprogrammet på Kungliga TekniskaHögskolan. Det främsta målet med analysen var att utreda Solvattens miljöpåverkan samt att jämföraden med två andra sätt att få tag på rent vatten; kokning och flaskvatten. Information har samlats ingenom att kontakta producenter och leverantörer och sedan analyserat med datorprogrammetSimaPro. Den fristående LCA:n av Solvatten visade att produkten nästan inte ger någon inverkan påekosystem kvalité och hälsa. Eftersom produkten mestadels är gjord utav olika plastmaterial (d.v.s.fossila bränslen), visar analysen högst påverkan i kategorin för råvaror (eng: resources). Den störstadelen av Solvatten’s miljöpåverkan kommer ifrån materialen och produktions processerna för densvarta delen av dunken samt de genomskinliga locken. Avfallshanteringen för Solvatten fickutelämnas ur dataanalysen, då osäkerheten kring olika metoder för avfallshantering är för stor iutvecklingsländer. Istället gjordes en jämförelse mellan tre olika avfallsscenarion; deponering,förbränning och återvinning med europeiska standarder. Det är tydligt att återvinning är det bästaalternativet, och att Solvatten AB borde visa sitt samhällsansvar genom att organisera detta. Denjämförande studien mellan Solvatten, kokning och flaskvatten indikerar att Solvatten har den lägstamiljöpåverkan, på grund av produktens långa livslängd. Rapporten diskuterar även Solvattenshållbarhet ur ekonomiska och sociala perspektiv. De visar att Solvatten har stora fördelar i att bådetid och pengar kan sparas. Slutsatsen är att Solvatten är ett bra alternativ för att få tillgång till rentvatten.
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Isberg, Ulrika, and Karin Nilsson. "Life Cycle Assessment and Sustainability Aspects of Solvatten, a Water Cleaning Device." Thesis, KTH, Industriell ekologi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-127694.
Full textAbstract:
Solvatten is a water cleaning device for households in developing countries. As a Master Thesis forthe Master of Science in Engineering Programme at Kungliga Tekniska Högskolan a Life CycleAssessment of Solvatten has been conducted. The primary aim was to investigate the environmentalimpacts of Solvatten and compare it with two other common methods of accessing safe water;boiling and bottled water. Information has been gathered by contacting manufacturers and suppliersand analysed in the computer software SimaPro. The stand-‐alone LCA of Solvatten showed that theproduct gives almost no impact on ecosystem quality and human health. As the product mostly ismade of different plastic materials (i.e. fossil fuels), Solvatten has its highest impact in the damagecategory of resources. Hence, most of Solvatten’s environmental impact comes from the materialsand production processes of the black container and the transparent lid. The disposal phase ofSolvatten has been left out of the data analysis as there is a large uncertainty in waste scenarios ofdeveloping countries. Instead, a comparison was made between three different waste scenarios;landfill, incineration, and recycling with European standards. It is clear that recycling is the bestalternative, and Solvatten should show their corporate social responsibility by organizing this. Thecomparative studies conducted for Solvatten, boiling water with firewood and buying bottled waterindicated that due to Solvatten’s long lifetime, the environmental impact for Solvatten is lower. Alsodiscussed in the report are the economic and social aspects of Solvatten, which are a great advantagefor Solvatten since both time and money can be saved. Solvatten is concluded to be a goodalternative for accessing safe water.Solvatten är en produkt för att rena vatten i hushåll i utvecklingsländer. En livscykelanalys avSolvatten har gjorts som examensarbete för civilingenjörsprogrammet på Kungliga TekniskaHögskolan. Det främsta målet med analysen var att utreda Solvattens miljöpåverkan samt att jämföraden med två andra sätt att få tag på rent vatten; kokning och flaskvatten. Information har samlats ingenom att kontakta producenter och leverantörer och sedan analyserat med datorprogrammetSimaPro. Den fristående LCA:n av Solvatten visade att produkten nästan inte ger någon inverkan påekosystem kvalité och hälsa. Eftersom produkten mestadels är gjord utav olika plastmaterial (d.v.s.fossila bränslen), visar analysen högst påverkan i kategorin för råvaror (eng: resources). Den störstadelen av Solvatten’s miljöpåverkan kommer ifrån materialen och produktions processerna för densvarta delen av dunken samt de genomskinliga locken. Avfallshanteringen för Solvatten fickutelämnas ur dataanalysen, då osäkerheten kring olika metoder för avfallshantering är för stor iutvecklingsländer. Istället gjordes en jämförelse mellan tre olika avfallsscenarion; deponering,förbränning och återvinning med europeiska standarder. Det är tydligt att återvinning är det bästaalternativet, och att Solvatten AB borde visa sitt samhällsansvar genom att organisera detta. Denjämförande studien mellan Solvatten, kokning och flaskvatten indikerar att Solvatten har den lägstamiljöpåverkan, på grund av produktens långa livslängd. Rapporten diskuterar även Solvattenshållbarhet ur ekonomiska och sociala perspektiv. De visar att Solvatten har stora fördelar i att bådetid och pengar kan sparas. Slutsatsen är att Solvatten är ett bra alternativ för att få tillgång till rentvatten.
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Govindaraju, Sirisha D. "Analysis of absorber operations for the 5 kw ammonia/water combined cycle." [Gainesville, Fla.] : University of Florida, 2005. http://purl.fcla.edu/fcla/etd/UFE0010828.
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Gibbons, Heather Louise. "Climate change and the carbon cycle of a small, hard water lake." Thesis, University of Liverpool, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.440752.
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Gao, Ge. "Changes of evapotranspiration and water cycle in China during the past decades." Göteborg : University of Gothenborg, 2010. http://hdl.handle.net/2077/21737.
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Webster, Jack Ryan. "Suitability of the Kalina Cycle for Power Conversion from Pressurized Water Reactors." BYU ScholarsArchive, 2018. https://scholarsarchive.byu.edu/etd/6882.
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The primary objective of this work is to determine the Kalina cycle's suitability for thermal power conversion from a pressurized water reactor. Several previous papers have examined this application, but these either lack proof of concept or make unfeasible assumptions. This work expands current knowledge by simulating the Kalina cycle and comparing it to current pressurized water reactor Rankine cycles in order to identify which is more efficient. Prerequisite to the modeling is a simulation tool capable of modeling the thermodynamics of ammonia/water mixtures. Instead of using an existing program, a new one called Clearwater is used. This tool is based on a preexisting Gibbs free energy "super" equation of state. Algorithms for vapor-liquid equilibrium calculations and phase identification are presented. Clearwater will be distributed online as open-source code to aid future developers of ammonia/water power and refrigeration cycles. A comparison of single-stage Kalina and Rankine cycles driven by heat from PWR core coolant suggests that the Kalina cycle is not well suited to the application. Any benefit from the Kalina cycle's ability to match temperature profiles in the boiling region of the steam generator is outweighed by other drawbacks. These include the cycle's 1) increased turbine exhaust pressure and 2) lower average heat absorption temperature caused by its working fluid's relatively high liquid heat capacity, both of which lower efficiency. Having concluded this, an attempt is made to quantify the conditions under which the Kalina cycle produces more power than the Rankine cycle. Both cycles are optimized for a range of heat source inlet and outlet temperatures between 350 ℃ and 525 ℃. When both cycles absorb the same amount of heat from the source"”i.e., when source outlet temperature is constrained"” the Kalina cycle is less effective for small source temperature drops. When outlet temperature is unconstrained, the Kalina cycle outperforms the Rankine cycle for all but the lowest inlet temperature. This is due to the Kalina cycle's non-isothermal boiling profile, which allows it to absorb low temperature heat at relatively high pressure. Because of its isothermal boiling profile, the Rankine cycle cannot capture low temperature heat as effectively, so it performs worse over large, unconstrained source temperature drops.
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Hunter, Michael. "Behaviour of nitrilotriacetic acid in the wastewater disposal and water reuse cycle." Thesis, Imperial College London, 1987. http://hdl.handle.net/10044/1/47503.
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Ghashami, Bahman. "A New Power Storage, Cooling Storage, and Water Production Combined Cycle (PCWCC)." Thesis, Högskolan i Gävle, Energisystem, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-22725.
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Fresh water shortage and hot weather are common challenges in many countries of the world. In the other hand, the air conditioning systems which are used for indoor cooling cause peak electricity demand during high temperatures hours. This peak hour demand is very important since it is more expensive and mainly is supplied by fossil fuel power plants with lower efficiencies compare to base load fossil fuel or renewable owe plants. Moreover, these peak electricity load fossil fuel power plants cause higher green house gas emission and other environmental effects. So, all these show that any solution for these problems could make life better in those countries and all over the world.In this thesis, a new idea for a Power storage, Cooling storage, and Water production Combined Cycle (PCWCC) is introduced and reviewed. PCWCC is combination of two thermal cycles, Ice Thermal Energy Storage (ITES) and desalination by freezing cycle, which are merged together to make a total solution for fresh water shortage, required cooling, and high peak power demand. ITES is a well known technology for shifting the electricity demand of cooling systems from peak hours to off-peak hours and desalination by freezing is a less known desalination system which is based on the fact that the ice crystals are pure and by freezing raw water and melting resulted ice crystals, pure water will be produced. These two systems have some common processes and equations and this thesis shows that by combining them the resulted PCWCC could be more efficient than each of them. In this thesis, the thermodynamic equations and efficiencies of each PCWCC sub-systems are analyzed and the resulted data are used in finding thermodynamics of PCWCC itself. Also, by using reMIND software, which uses Cplex to find the best combinations of input/output and related processes, the cost of produced fresh water and cooling from PCWCC is compared with total cost of fresh water and cooling produced by each sub-systems of PCWCC in three sample cities all over the world, Kerman, Dubai, and Texas. These cities are chosen since they have similar ambient temperature trend with different electricity and fresh water tariff's. The results show that, the PCWCC is economical where there is a significant electricity price difference between ice charging and ice melting hours, off-peak and peak hours, of the day or when the fresh water price is high compare to electricity price. The results also show that how the revenue from fresh water could cover the used electricity cost and make some income as well.
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Lemos, Diogo Siqueira. "Urban metabolism of Aveiro: LCA of the city demands and water cycle." Master's thesis, Universidade de Aveiro, 2011. http://hdl.handle.net/10773/7419.
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Mestrado em Estudos AmbientaisThis study analyzed the urban metabolism of the city of Aveiro with a consumption-based perspective. The MFA coupled city scale data of energy, water, wastewater and solid waste with downscaled national data, getting a total mass of inputs equal to 163 kg/cap/day and of outputs equal to 148 kg/cap/day, the difference being due to net accumulation. An economic IO analysis was done for the household expenses and found a total impact of 26 kg CO2-eq./cap/day for climate change (CC) and 7 kg oil eq./cap/day for fossil depletion (FD). The process LCA was done using the products and processes quantities estimated with the MFA. The process LCA total impacts were 27 kg CO2-eq./cap/day for CC, 8 kg oil eq./cap/day for FD and 3 points/cap/day for the ReCiPe endpoint impact. It allowed also the discrimination of products that contributed to more than 1% of each impact (priority products). Process LCA was also applied to the water cycle of Aveiro to compare local impact factors with the ones used from LCA databases. It was observed that the local impact factors of the water cycle were more than 2 times higher, showing the importance of carrying detailed local studies, especially for priority products.
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Robinson, A. W. "Water relations and the control of flush growth in Theobroma cacao L." Thesis, University of Liverpool, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.380125.
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Mulas, Dani. "Levels and behaviour of radionuclides in water treatment plants : the case of the Barcelona metropolitan area urban water cycle." Doctoral thesis, Universitat Politècnica de Catalunya, 2020. http://hdl.handle.net/10803/668856.
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The Barcelona metropolitan area (BMA; 3.2 M inhabitants) has an integrated urban water cycle management. Different type of treatment plants are located along the drinking, sewerage and reuse networks where specific treatments are applied to guarantee a good enough standard of the water quality. The presence of radionuclides in treatment plants and in the aquatic environment is well known. Primordial and daughters, cosmogenic, global fall-out and nuclear-legacy radionuclides can be found in the urban water cycle. Moreover in nuclear medicine (NM), short-lived radionuclides are administered to patients, excreting part directly into the sewage network and entering into the urban water cycle. Thus, the levels of radionuclides in waters and materials from water treatment plants were experimentally checked in the BMA in order to understand the behaviour during the water treatment and to perform a risk assessment. An integrated study focused on the study of the radionuclides levels at different three types of water treatment plants from the same network was carried out. A total of 233 samples were taken at 1 drinking water treatment plant (DWTP), 7 wastewater treatment plants (WWTPs) and 1 reclaimed water treatment plant (RWTP). The concentrations were determined by gamma-spectroscopy techniques after acquisitions performed by high-purity germanium detectors. Primordial and daughters radionuclides were found in materials from the DWTP studied and the highest specific activities found for sludge, sand and reverse osmosis brine corresponded to K-40. Nevertheless, the maximum concentration in the case of granular activated carbon was found for U-238. Moreover cosmogenic Be-7 and fall-out Cs-137 were found in sludges. A total of 5 different NM radionuclides were found in the analysis carried out in the samples from the 7 WWTPs. In the case of water and sewage sludge the highest maximum values and detection frequencies corresponded to Tc-99m and I-131. Moreover Ga-67, In-111 and I-123 were found but showing significantly lower levels. The detection frequencies and the mean levels found at the WWTPs of Ga-67, Tc-99m, In-111 and I-131 agreed with the NM radionuclides total activity administered in the region studied. Furthermore the concentrations and detection frequencies were significantly higher in the sewage sludge samples taken at the very large-sized WWTP-1 (325,000 m3/d), partially explained by their low sludge age. Medically-derived I-131 was also found in reclaimed water for reuse from the RWTP and materials from DWTP, which represent novel contributions to the current knowledge in this field.
Taking into account the present findings some considerations from the radiological protection point of view can be done. Despite the presence of radionuclides in the DWTP materials, they do not pose a radiological risk. In the case of the WWTPs and the RWTP studied, the levels found in waters and materials do not represent a significant risk, however, I-131 concentrations were pointed out as the most significant. With the aim to achieve a better understanding of I-131 behaviour in WWTPs and predict the I-131 levels novel methods of I-131 partitioning analysis as well as prognosis models were adapted successfully to a WWTP. I-131 partitioning results pointed out that the settling fraction predominates in the reactor while in the rest of the WWTP samples dissolved iodide fraction was the most significant. Furthermore the activated sludge reactors from WWTPs were revealed as the key step for I-131 removal from wastewater. Specifically, reactors with the highest total nitrogen kjeldahl removal were also the most effective for I-131 reduction. Regarding the I-131 modelling a total of 82 % of simulated data fit with the experimental results in the sewage effluent within uncertainties.El Área Metropolitana de Barcelona (AMB; 3.2 M de habitantes) posee un sistema integrado para la gestión del ciclo urbano del agua con diferentes tipos de plantas de tratamiento. En las redes de agua potable, residual y regenerada se aplican tratamientos específicos para garantizar los estándares de calidad requeridos en cada caso. Estudios previos en plantas de tratamiento de aguas revelan la presencia de radionúclidos primordiales y de su cadena de desintegración, cosmogénicos y procedentes de accidentes y del legado nuclear. Además, en medicina nuclear (MN) radionúclidos artificiales de vida corta son administrados a pacientes, dichos isótopos son posteriormente excretados entrando en el ciclo urbano del agua a través del agua residual. En el presente estudio en el AMB las concentraciones de radionúclidos en aguas y materiales de las plantas de tratamiento se han estudiado de forma integrada con el objetivo de determinar su comportamiento durante el tratamiento y realizar una evaluación radiológica de los niveles. El estudio ha incluido 233 muestras tomadas en tres tipos diferentes de plantas de tratamiento, 7 estaciones depuradoras de agua residual (EDAR), 1 estación de regeneración de agua (ERA) y de 1 estación de tratamiento de agua potable (ETAP). Las concentraciones de radionúclidos se han determinado con detectores de germanio de alta pureza mediante la aplicación de técnicas de espectrometría gamma. Radionúclidos primordiales y de su cadena de desintegración fueron detectados en los materiales sólidos de la ETAP. Las actividades más altas en el caso de los fangos, las arenas y el rechazo del osmosis inversa correspondieron al K-40 mientras que en el caso de carbón activo granulado al U-238. Además, se confirmó la presencia de Be-7 y Cs-137. Un total de 5 radionúclidos relacionados con la MN fueron detectados en los análisis de las muestras de las 7 EDARs. Respecto a las aguas y los fangos analizados las máximas concentraciones y los más detectados fueron el Tc-99m y el I-131. Además, fueron detectados en concentraciones más bajas el Ga-67, In-111 y el I-123. Las frecuencias de detección y niveles concordaron con la actividad total administrada en la zona de estudio. Especial mención merecen los resultados de la EDAR-1 (325,000 m3/d), de grandes dimensiones, ya que los valores y frecuencia de detección fueron mayores que en el resto lo que se explica en parte por la reducida edad del fango que genera. El I-131 se encontró también en agua regenerada de la ERA y los materiales de EDAR estudiadas, lo que representa una nueva aportación por a lo que I-131 de origen médico se refiere. Con los presentes resultados se pueden realizar las siguientes consideraciones desde el punto de vista de la protección radiológica. A pesar de la presencia de radionúclidos en aguas y materiales de las plantas estudiadas, las concentraciones de actividad determinadas no suponen un riesgo radiológico significativo. Sin embargo, puede afirmarse que las concentraciones de I-131 fueron las más relevantes. Con el objetivo de avanzar en el conocimiento del comportamiento de I-131 en EDARs y predecir sus concentraciones nuevas metodologías de análisis del I-131 así como modelos predictivos se adaptaron satisfactoriamente a una de las EDAR estudiadas. La distribución fisicoquímica del I-131 resultó en que la fracción precipitable predominó en las muestras tomadas en el reactor ya que es un tratamiento clave para su eliminación, mientras que en el resto de muestras analizadas el yodo inorgánico disuelto fue mayoritario. Otro descubrimiento relevante fue constatar que los reactores que presentaban una mayor disminución de la concentración del nitrógeno kjeldahl mostraron también una reducción significativa del I-131. Respecto al modelo, un total del 82 % de las concentraciones de I-131 simuladas para los efluentes de planta se ajustaron satisfactoriamente a los resultados experimentales considerando las incertidumbres
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Schwartz, Kerry, and Holly Thomas-Hilburn. "Arizona Project WET Water Festivals: A Summative Evaluation." College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2011. http://hdl.handle.net/10150/156933.
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13 pp.The Make a Splash with Project WET Arizona Water Festival program is in its ninth year and served 12 communities in the 2008-2009 school year. The program trained 622 volunteers to deliver engaging water education to 6,924 fourth graders and their 313 teachers. With the support of the Bureau of Reclamation, Arizona Project WET has conducted a summative evaluation, and is able to use that information to further increase the effectiveness of the program while simultaneously documenting successes in student learning and community engagement in water education.
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Francis, Todd Michael. "Dissociation of manganese(III) oxide as part of a thermochemical water splitting cycle." Connect to online resource, 2008. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3337093.
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Maurer, John H. (John Howard). "Surveillance strategy for a four year operating cycle in commercial boiling water reactors." Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/39051.
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Weinmann, Julian. "Influence of the Martian regolith on the atmospheric methane and water vapour cycle." Thesis, Luleå tekniska universitet, Rymdteknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-75897.
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Context. The Martian methane and water cycle are subject of ongoing research through simulation. Exchange with the subsurface has a potentially strong impact, but is often neglected. Aims. For methane, I determine if adsorption with an increased enthalpy can explain the observed seasonal variations and conflicting observations by the Trace Gas Orbiter and the Curiosity rover. For water, the impact of adsorption and ice formation in the subsurface on the global cycle is studied. A new way of initializing the soil, by running a decoupled subsurface model, is tested. Depths of stable subsurface ice and subsurface water distributions are studied. Methods. A General Circulation Model (GCM) is used with a purely diffusive subsurface model. For methane, different initial states, source scenarios, and decay times are tested. For water, a model without an active atmosphere is implemented to provide an initial state. The effect of the subsurface with this initial state on the full atmospheric water cycle is tested. Results. For methane, a strong influence on the global methane cycle is observed. Seasonal variations measured at Gale Crater are reproduced, but the conflicting observations cannot be explained by adsorption. For water, the new initialization can be used without completely disrupting the water cycle. It leads to a generally wetter atmosphere, in conflict with observations. Found ice table depths do not match well with observations, but ice profiles reproduce previous findings. Conclusion. Methane adsorption is able to partly explain observed variations, but cannot be the only process to influence methane abundances. The new initialization method for water works well in principle, but a more refined model is needed for more realistic results.
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Egeskog, Ylva, and Jannik Scheer. "Life Cycle and Water Footprint Assessment of Palm Oil Biodiesel Production in Indonesia." Thesis, KTH, Energi och klimatstudier, ECS, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-182695.
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FitzHarris, Heidi Sue Blycker. "Celebrating the Natural Cycle of Life: A Birthing and Hospice Center." Thesis, Virginia Tech, 2006. http://hdl.handle.net/10919/35758.
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When the special moments of life and death are imminent, where do you want to be?
My thesis seeks to create an eco-sensitive, sustainable building that celebrates the time and place of two of life s most amazing events: birth and death. Rather than a conventional singular center, my thesis proposes a combined program for a new architectural project type: a Birthing and Hospice Center. Although the concept may be surprising, once people fully understand that we live in a closed system and embrace the cyclical nature of life, it is an appropriate program that represents another aspect of sustainability. The project site is located in an urban area of Old Town Alexandria, Virginia along the Potomac River.
The Birthing and Hospice Center integrates both the human life cycle and the material life cycle of the building s materials, water, and site for a holistic experience and celebration. It explores how to heighten our environmental experience of place, light, air, water, and time. My thesis seeks to create a beautiful place where people can celebrate their own special event, while at the same time, understand and celebrate the larger realm of the natural life cycle.Master of Architecture
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Orre, Adam, and Axel Pers. "The Environmental Effects of Water Damages : Assessing the CO2e footprint of water damage resolution methods from a life cycle perspective." Thesis, KTH, Skolan för industriell teknik och management (ITM), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-264102.
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This study assesses the primary drivers of CO2e footprint for three types of water damage resolution methods and identifies relevant focus areas to support a reduced environmental footprint from water damage restoration. To face the global challenge of climate change, mitigation actions need to be taken on a broad level, with the reduction of greenhouse gas emissions from buildings being a key part. Although the number of environmental assessments of buildings is increasing, there is a lack of scientific literature quantifying the CO2e footprint of water damages, which makes it difficult for stakeholders in the industry to make sound decisions in order to combat climate change. In particular, this relates to the various methods that can be applied to resolve water damages. Therefore, this study conducts an attributional life cycle assessment of the CO2e footprint of three actual water damages, resolved using different methods requiring various degrees of material replacement. The study finds that both the total CO2e footprint and its main drivers vary significantly depending on the selected method. It further finds that the choice of method is crucial in order to reduce the CO2e footprint from water damage restoration, more specifically that a higher degree of material reuse, enabled by drying of damaged materials, appears to be preferred where applicable.Denna studie undersöker de huvudsakliga faktorerna som påverkar det koldioxidavtryck som kan kopplas till tre typer av hanteringsmetoder av vattenskador, samt identifierar relevanta områden att fokusera på för att minska den miljömässiga effekten från vattenskadehantering. Flertalet åtgärder behöver genomföras för att möta utmaningen med klimatförändringar, och att minska växthusgaser kopplade till byggnader är att anse som en viktig del av detta. Trots att antalet miljöstudier relaterade till byggnader ökar är antalet vetenskapliga studier kopplade till CO2e från vattenskador begränsat, vilket gör det svårt för intressenter i industrin att fatta välgrundade beslut. I synnerhet är detta relaterat till de olika metoder som kan användas för att hantera skadorna. Av den anledningen genomför denna studie en livscykelanalys med bokföringsmetodik för att undersöka koldioxidavtrycket från tre faktiska vattenskador. Dessa har åtgärdats med olika hanteringssmetoder vilket medför en variation i den mängd material som behöver bytas ut. Studien konstaterar att både det totala avtrycket samt de huvudsakliga drivarna varierar betydligt beroende på vilken metod som använts. Vidare konstateras att valet av metod är avgörande för att kunna minska mängden CO2e från vattenskadehantering, mer specifikt att en högre grad av materialåteranvädning, möjliggjort av torkning av skadade delar, förefaller vara att föredra när det är tillämpbart.
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Gingerich, Daniel Beryl. "Evaluating and Avoiding Risk Tradeoffs in Water Treatment." Research Showcase @ CMU, 2017. http://repository.cmu.edu/dissertations/997.
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Treating water in order to reduce human and environmental risks requires the use of electricity and chemicals, the generation of which creates emissions of air pollutants such as NOx, SO2, PM2.5, and CO2. Emissions of air pollutants establishes a health and environmental risk tradeoff between air and water pollution. Addressing air-water tradeoffs by adopting a one environment framework requires new methods for quantifying these tradeoffs, new technologies to minimize air-water tradeoffs, and new tools for decision makers to incorporate these tradeoffs into compliance decisions. In my thesis, I develop methods for quantifying damages from air emissions associated with water treatment; assess the feasibility of forward osmosis (FO), a technology which holds the promise to avoid air-water tradeoffs; and create a tool to holistically assess compliance with air and water emission standards for coal-fired power plants (CFPPs). I start my thesis by creating a method to quantify the damages caused by the air emissions that resulting from the treatment of drinking water (Chapter 2), municipal wastewater (Chapter 3), and flue gas desulfurization (FGD) wastewater (Chapter 4). These studies use life-cycle models of energy and chemical consumption for individual water treatment unit processes in order to estimate embedded emissions of criteria air pollutants and greenhouse gasses per cubic meter of treated water. Damages from these additional air emissions are assessed and incorporated into benefit-cost analyses. I find that for drinking water rules, the net benefit of currently implemented rules remains positive but the promises of net benefits for some proposed rules are conditional on the compliance technology that is selected. For municipal wastewater, I find that while there are ~$240 million (in 2012 USD) benefits in air emission reduction from installing biogas-fueled electricity generation nationwide, there are several states where biogas-fueled electricity creates more air emissions than it displaces. For FGD wastewater treatment, I find that complying with the effluent limitation guidelines has an expected ratio of benefits to cost of1.7-1.8, with damages concentrated in regions with large chemical manufacturing industries or electricity grids that are heavily reliant on coal. In the next part of the thesis, I assess the techno-economic feasibility of power plant waste heat driven FO to reduce the air emissions associated with FGD wastewater treatment. In Chapter 5, I assess the quantity, quality and the spatial and temporal availability of waste heat from US coal, nuclear, and natural gas power plants. I find that while 18.9 billion GJ of potentially recoverable waste heat is discharged into the environment, only 900 million GJ of that heat is from the flue gas and is at a temperature high enough to drive water purification using forward osmosis (FO). In Chapter 6, I build a model of FO to assess its thermal energy consumption and find that the 900 million GJ of waste heat produced at coal and natural gas power plants is sufficient to meet their boiler feedwater and FGD wastewater treatment needs. In Chapter 7, I incorporate cost into the energy consumption model of FO, and conclude that treatment of FGD and gasification wastewater using waste heat driven FO is economically competitive with mechanical vapor recompression. In Chapter 8, I create an energy-balance model of a CFPP and nine environmental control technologies for compliance with FGD wastewater and carbon capture regulations. I use this model to maximize plant revenue at the National Energy Technology Laboratory’s 550 MW model CFPP without carbon capture. I find that revenue is maximized by using residual heat for water treatment or carbon capture. If both carbon capture and zero liquid discharge water treatment regulatory standards are in place, I conclude that the plant maximizes revenue by allocating residual heat and steam to amine-based carbon capture and electricity to mechanical vapor recompression for FGD wastewater treatment.
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Williams, Timothy Dorian. "Life-cycle parameters of Tisbe battagliai (Copepoda: Harpacticoida) as indicators of chronic toxicity." Thesis, University of Plymouth, 1997. http://hdl.handle.net/10026.1/2786.
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There is growing concern about the fate and biological effects of chemical contaminants in the marine environment. In the United Kingdom, the present ability to detect the potential longterm effects of contaminants is limited by the lack of suitable laboratory methods for measuring chronic toxicity. The harpacticoid copepod Tisbe battagliai was selected as a candidate test organism and a suite of chronic toxicity test methods was developed for measuring the effect of chemical contaminants on individual copepods (postembryonic development, reproduction and life-table analysis) and populations of T battagliai. The development of chronic test methods proceeded alongside investigations of the influence of key environmental variables (temperature and food availability) on the biology of this species. These investigations provided a valuable insight into the potential importance of these environmental factors for influencing the development of populations of T battagliai in the field, and helped to define the optimum conditions for the culture and chronic toxicity testing of this species in the laboratory. The methods were further evaluated using pentachlorophenol (PCP) as a reference toxicant and the aim was to investigate the potential interaction between toxicant (PCP), environmental factors (temperature and food availability), and their effects on the population dynamics of T battagliai. In summary, results showed that temperature, and food quantity and quality, were important determinants of population dynamics. There were significant interactions between the chosen environmental variables (e. g. temperature), PCP, and subsequent biological effects on Tisbe battagliai, and results highlighted some important differences in toxicity testing approaches based on the measurement of individuals and populations of copepods. Established laboratory toxicity test procedures do not take account of the degree of complexity in the natural environment and this underlines the Miculty in extrapolating from laboratory. results to the field situation. In conclusion, the project was successful in its primary objective of developing a suite of techniques that can be used to measure the potential chronic toxicity of chemical contaminants in the marine environment. The methods using Tisbe battagliai are relatively simple to perform, are amenable to standardisation and provide relatively cost-effective measurements of chronic toxicity. The test methods can be used to provide chronic toxicity data but, more importantly, they can be used to address some of the current limitations associated with single species laboratory tests. For example, used in conjunction with key environmental variables, the methods provide a greater understanding of the potential interaction between contaminants and abiotic variables, thereby, improving the extrapolation of laboratory results to the field situation. The ability to carry out measurements on individual and populations of T. bauagliai provides a valuable insight into the predictive links between effects at different levels of biological organisation.
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Iles, Carley Elizabeth. "Effect of volcanic eruptions on the hydrological cycle." Thesis, University of Edinburgh, 2014. http://hdl.handle.net/1842/9918.
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Large explosive volcanic eruptions inject SO2 into the stratosphere where it is oxidised to sulphate aerosols which reflect sunlight. This causes a reduction in global temperature and precipitation lasting a few years. Here the robust features of this precipitation response are investigated, using superposed epoch analysis that combines results from multiple eruptions. The precipitation response is first analysed using the climate model HadCM3 compared to two gauge based land precipitation datasets. The analysis is then extended to a large suite of state-of-the art climate models participating in the Coupled Model Intercomparison Project Phase 5 (CMIP5). This is the first multi-model study focusing on the precipitation response to volcanoes. The large ensemble allows analysis of a short satellite based dataset which includes ocean coverage. Finally the response of major world rivers to eruptions is examined using historical records. Whilst previous studies focus on the response of just a few rivers or global discharge to single eruptions, here the response of 50 major world rivers is averaged across multiple eruptions. Results are applicable in predicting the precipitation response to future eruptions and to geoengineering schemes that seek to counteract global warming through reducing incoming solar radiation. The main model-simulated features of the precipitation response include a significant global drying over both land and ocean, which is dominated by the wet tropical regions, whilst the dry tropical ocean regions get significantly wetter following eruptions. Monsoon rainfall decreases, whilst in response to individual eruptions the Intertropical Convergence Zone shifts away from the hemisphere with the greater concentration of volcanic aerosols. The ocean precipitation response is longer lived than that over land and correlates with near surface air temperature, whilst the land response correlates with aerosol optical depth and a reduction in land-ocean temperature gradient Many of these modelled features are also seen in observational data, including the decrease in global mean and wet tropical regions precipitation over land and the increase of precipitation over dry tropical ocean regions, all of which are significant in the boreal cold season. The land precipitation response features were robust to choice of dataset. Removing the influence of the El Nino Southern Oscillation (ENSO) reduces the magnitude of the volcanic response, as several recent eruptions coincided with El Nino events. However, results generally remain significant after subtraction of ENSO, at least in the cold season. Over ocean, observed results only match model expectations in the cold season, whilst data are noisy in the warm season. Results are too noisy in both seasons to confirm whether a long ocean precipitation response occurs. Spatial patterns of precipitation response agree well between observational datasets, including a decrease in precipitation over most monsoon regions. A positive North Atlantic Oscillation-like precipitation response can be seen in all datasets in boreal winter, but this is not captured by the models. A detection analysis is performed that builds on previous detection studies by focusing specifically on the influence of volcanoes. The influence of volcanism on precipitation is detectable using all three observational datasets in boreal winter, including for the first time in a dataset with ocean coverage, and marginally detectable in summer. However, the models underestimate the size of the winter response, with the discrepancy originating in the wet tropics. Finally, the number of major rivers that undergo a significant change in discharge following eruptions is slightly higher than expected by chance, including decreased flow in the Amazon, Congo, Nile, Orange, Ob and Yenisey. This proportion increases when only large or less humanly influenced basins are considered. Results are clearer when neighbouring basins are combined that undergo the same sign of CMIP5 simulated precipitation response. In this way a significant reduction in flow is detected for northern South American, central African and less robustly for high-latitude Asian rivers, along with a significant increase for southern South American and SW North American rivers, as expected from the model simulated precipitation response.
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Hass, Ulrike [Verfasser]. "Analysis, occurrence, and fate of psychoactive compounds in an urban water cycle / Ulrike Hass." Berlin : Freie Universität Berlin, 2012. http://d-nb.info/1030488061/34.
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Moore, Thomas Joseph. "A surveillance strategy for a four year operating cycle in commercial pressurized water reactors." Thesis, Springfield, Va. : Available from National Technical Information Service, 1996. http://handle.dtic.mil/100.2/ADA313804.
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Thesis (Degree of Nuclear Engineer and M.S. in Nuclear Engineering)--Massachusetts Institute of Technology, May 1996.Todreas, Neil E. ; Golay, Michael W. "May 1996." Includes bibliographical references. Also available online.