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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

Waterworks

Brogren Meijel, Erik January 2023 (has links)
An investigation into the reasons behind the water shortage on Gotland. The project investigated several key factors and proceeded with the design of a surface water treatment plant in one of Gotlands old quarries left behind by the cement industry. The project also investigated and questioned the traditional methods of designing infrastructural buildings through a more architectural lens. The hope was to show a proposal that works but also acts as a pedagogical invitation to learn about where our most important resource comes from.
92

Ökonomische und ökologische Bewertung der Auswirkungen des demografischen Wandels auf die Siedlungsentwässerung

Müller, Josephine, Schubert, Rebecca, Woite, Martin 17 April 2013 (has links) (PDF)
Im ersten Teil dieser Arbeit „Metaanalyse vorhandener Ökobilanzen der Siedlungsentwässerung“ wird mit Hilfe einer qualitativen Metaanalyse vorhandener Ökobilanzen der Siedlungsentwässerung untersucht, welche wichtigen Stellschrauben es in der Umweltleistung von Abwasserreinigungsanlagen gibt und welchen Einfluss diese auf den demographischen Wandel haben. Die Ergebnisse zeigen Stromverbrauch, Schlamm und damit verbundene Toxizität sowie Eutrophierung als Indikatoren der Umweltleistung der Abwasserreinigung, die zur Reaktion auf den demographischen Wandel berücksichtigt werden müssen. Im zweiten Tei. „Ökologische Analyse des Gesamtsystems der Siedlungsentwässerung unter Betrachtung des Siedlungsanschlusses“ werden die ökologischen Auswirkungen des Gesamtsystems der Abwasserentsorgung über den gesamten Lebenszyklus analysiert. Die Arbeit kommt zu dem Ergebnis, dass diese Entscheidung für ein zentrales oder ein dezentrales System sowohl von der Siedlungsgröße, als auch von der Entfernung zur bestehenden Kläranlage abhängig ist. Der dritte Teil „Ökologische Analyse von Kleinkläranlagen“ analysiert eine Alternative zur in Deutschland üblichen Methode der Abwassereinigung durch eine zentrale Kläranlage. Die Kleinkläranlage ist eine dezentrale Lösung für die Haushalte, die nicht an das kommunale Abwassernetz angeschlossen werden. In der Arbeit wird eine SBR-Anlage im Hinblick auf ihre ökologischen Auswirkungen mittels einer Ökobilanzierung mit Hilfe der Software SimaPro untersucht.
93

Tratamento e recuperação da água de lavagem dos filtros de uma estação de filtração direta e simulação da disposição dos lodos em estações de tratamento de esgoto / Treatment and recovery of wastes from backwash filter on direct filter water treatment systems and simulation of sludge disposal in wastewater treatment systems

Escobar Rivera, Juan Carlos 16 February 2001 (has links)
Foi pesquisada a aplicação de métodos, em nível de laboratório, através dos quais é possível otimizar, tratar e dispor resíduos de lavagem de filtros de estações de tratamento de água (Caso ETA do rio Descoberto - ETA-RD Brasília). Na clarificação da água de lavagem dos filtros, observou-se o efeito favorável da adição de polímero para melhorar a separação líquido-sólido é, portanto, as eficiências de remoção de turbidez, cor aparente, sólidos suspensos e coliformes totais. Observou-se melhor sedimentabilidade do lodo a ser desaguado. Os ensaios de centrifugação, em escala de bancada, mostraram que o método aplicado auxilia na determinação da dosagem a ser usada numa centrífuga em escala real. Foram avaliados três métodos de disposição do lodo adensado da ETA-RD em ETE: 1) sedimentação com esgoto sanitário e posterior digestão anaeróbia do lodo; 2) Digestão anaeróbia e 3) digestão aeróbia. Os melhores resultados foram obtidos com a digestão anaeróbia. Os estudos realizados mostraram que há diversas alternativas de tratamento e disposição desses resíduos, mas é necessário, sempre que possível, a avaliação das diferentes alternativas para selecionar a(s) mais apropriada(s) a cada caso em particular, pois fatores como custos e disponibilidade de de sistemas ou equipamentos, definirão a aplicabilidade ou não de determinado método. / It was researched the application of methods on laboratory bench scale to optimize the reuse, treatment and disposal of wastes from filter backwash of Water Treatment Plant - WTP (WTP-RD Descoberto River, Brasília case). In the clarification process of this waste, favorable effect of addition of polymer for best liquid-solid separation and, thus, better removal efficiencies of turbidity, apparent color, suspended solids and total coliforms was observed. Better sedimentability of the sludge occurred. The centrifugation tests showed that the applied method help on determination of dosagem to be used in full scale. Three methods to dispose thickened sludge of WTP-RD on wastewater treatment Plants - WWTP were evaluated: 1) Sedimentation with domestic sewage and anaerobic digestion of sludge; 2) Anaerobic digestion and 3) Aerobic digestion. Best results were obtained with anaerobic digestion. The results showed that there are alternatives of treatment and disposal of wastes of WTP, but is necessary, if possible, to make the evaluation of this alternatives to select the most appropriate(s) in each case because factors as costs, systems or equipments availability, will define the applicability or not of a particular method.
94

Tratamento e recuperação da água de lavagem dos filtros de uma estação de filtração direta e simulação da disposição dos lodos em estações de tratamento de esgoto / Treatment and recovery of wastes from backwash filter on direct filter water treatment systems and simulation of sludge disposal in wastewater treatment systems

Juan Carlos Escobar Rivera 16 February 2001 (has links)
Foi pesquisada a aplicação de métodos, em nível de laboratório, através dos quais é possível otimizar, tratar e dispor resíduos de lavagem de filtros de estações de tratamento de água (Caso ETA do rio Descoberto - ETA-RD Brasília). Na clarificação da água de lavagem dos filtros, observou-se o efeito favorável da adição de polímero para melhorar a separação líquido-sólido é, portanto, as eficiências de remoção de turbidez, cor aparente, sólidos suspensos e coliformes totais. Observou-se melhor sedimentabilidade do lodo a ser desaguado. Os ensaios de centrifugação, em escala de bancada, mostraram que o método aplicado auxilia na determinação da dosagem a ser usada numa centrífuga em escala real. Foram avaliados três métodos de disposição do lodo adensado da ETA-RD em ETE: 1) sedimentação com esgoto sanitário e posterior digestão anaeróbia do lodo; 2) Digestão anaeróbia e 3) digestão aeróbia. Os melhores resultados foram obtidos com a digestão anaeróbia. Os estudos realizados mostraram que há diversas alternativas de tratamento e disposição desses resíduos, mas é necessário, sempre que possível, a avaliação das diferentes alternativas para selecionar a(s) mais apropriada(s) a cada caso em particular, pois fatores como custos e disponibilidade de de sistemas ou equipamentos, definirão a aplicabilidade ou não de determinado método. / It was researched the application of methods on laboratory bench scale to optimize the reuse, treatment and disposal of wastes from filter backwash of Water Treatment Plant - WTP (WTP-RD Descoberto River, Brasília case). In the clarification process of this waste, favorable effect of addition of polymer for best liquid-solid separation and, thus, better removal efficiencies of turbidity, apparent color, suspended solids and total coliforms was observed. Better sedimentability of the sludge occurred. The centrifugation tests showed that the applied method help on determination of dosagem to be used in full scale. Three methods to dispose thickened sludge of WTP-RD on wastewater treatment Plants - WWTP were evaluated: 1) Sedimentation with domestic sewage and anaerobic digestion of sludge; 2) Anaerobic digestion and 3) Aerobic digestion. Best results were obtained with anaerobic digestion. The results showed that there are alternatives of treatment and disposal of wastes of WTP, but is necessary, if possible, to make the evaluation of this alternatives to select the most appropriate(s) in each case because factors as costs, systems or equipments availability, will define the applicability or not of a particular method.
95

Stanovení vybraných hormonálních přípravků pomocí kapalinové chromatografie s hmotnostním detektorem / Determination of selected hormonal drugs using liquid chromatography with mass detection

Jurasová, Lenka January 2012 (has links)
This master’s thesis is focused on optimizing of the analytical method for the determination of selected drugs - estrone, estradiole, ethynylestradiol, estriole, diethylstilestrole, norethindrone, mestranole and progestrone in wastewater using liquid chromatography with mass spectrometry (LC/MS). Solid phase extraction (SPE) using Oasis HLB cartridges was chosen extraction method Different mobile phase, temperature, flow rates and mobil phase gradient were during the process of optimization. Samples of the wastewater were collectedat the inflow and outlow of the wastewater treatment plant in Břeclav and in University of Veterinary and Pharmaceutical Sciences Brno. Drugs were isolated from wastewater and preconcentrated using solid phase extraction (SPE) and determined by high performance liquid chromatography with mass spectrometric detection (HPLC/MS).
96

Ökonomische und ökologische Bewertung der Auswirkungen des demografischen Wandels auf die Siedlungsentwässerung: Teil 3: Ökologische Bewertung

Müller, Josephine, Schubert, Rebecca, Woite, Martin January 2011 (has links)
Im ersten Teil dieser Arbeit „Metaanalyse vorhandener Ökobilanzen der Siedlungsentwässerung“ wird mit Hilfe einer qualitativen Metaanalyse vorhandener Ökobilanzen der Siedlungsentwässerung untersucht, welche wichtigen Stellschrauben es in der Umweltleistung von Abwasserreinigungsanlagen gibt und welchen Einfluss diese auf den demographischen Wandel haben. Die Ergebnisse zeigen Stromverbrauch, Schlamm und damit verbundene Toxizität sowie Eutrophierung als Indikatoren der Umweltleistung der Abwasserreinigung, die zur Reaktion auf den demographischen Wandel berücksichtigt werden müssen. Im zweiten Tei. „Ökologische Analyse des Gesamtsystems der Siedlungsentwässerung unter Betrachtung des Siedlungsanschlusses“ werden die ökologischen Auswirkungen des Gesamtsystems der Abwasserentsorgung über den gesamten Lebenszyklus analysiert. Die Arbeit kommt zu dem Ergebnis, dass diese Entscheidung für ein zentrales oder ein dezentrales System sowohl von der Siedlungsgröße, als auch von der Entfernung zur bestehenden Kläranlage abhängig ist. Der dritte Teil „Ökologische Analyse von Kleinkläranlagen“ analysiert eine Alternative zur in Deutschland üblichen Methode der Abwassereinigung durch eine zentrale Kläranlage. Die Kleinkläranlage ist eine dezentrale Lösung für die Haushalte, die nicht an das kommunale Abwassernetz angeschlossen werden. In der Arbeit wird eine SBR-Anlage im Hinblick auf ihre ökologischen Auswirkungen mittels einer Ökobilanzierung mit Hilfe der Software SimaPro untersucht.
97

Modelový výzkum účinnosti separačních technologií úpravy vody / The efficiency of water treatment separation processes – model research

Vašalovská, Petra January 2012 (has links)
Goal of this research was to recognize dissolved air flotation efficiency by the help of turbidity and UV absorbance removal for different conditions. As different conditions are meant the efficiency for different baffle position, different detention time in separation zone and checking results with adding chemicals compared to results without adding chemicals.
98

Water Supply System Management Design and Optimization under Uncertainty

Chung, Gunhui January 2007 (has links)
Increasing population, diminishing supplies and variable climatic conditions can cause difficulties in meeting water demands. When this long range water supply plan is developed to cope with future water demand changes, accuracy and reliability are the two most important factors. To develop an accurate model, the water supply system has become more complicated and comprehensive structures. Future uncertainty also has been considered to improve system reliability as well as economic feasibility.In this study, a general large-scale water supply system that is comprised of modular components was developed in a dynamic simulation environment. Several possible scenarios were simulated in a realistic hypothetical system. In addition to water balances and quality analyses, construction and operation of system components costs were estimated for each scenario. One set of results demonstrates that construction of small-cluster decentralized wastewater treatment systems could be more economical than a centralized plant when communities are spatially scattered or located in steep areas.The Shuffled Frog Leaping Algorithm (SFLA), then, is used to minimize the total system cost of the general water supply system. Decisions are comprised of sizing decisions - pipe diameter, pump design capacity and head, canal capacity, and water/wastewater treatment capabilities - and flow allocations over the water supply network. An explicit representation of energy consumption cost for the operation is incorporated into the system in the optimization process of overall system cost. Although the study water supply systems included highly nonlinear terms in the objective function and constraints, a stochastic search algorithm was applied successfully to find optimal solutions that satisfied all the constraints for the study networks.Finally, a robust optimization approach was introduced into the design process of a water supply system as a framework to consider uncertainties of the correlated future data. The approach allows for the control of the degree of conservatism which is a crucial factor for the system reliabilities and economical feasibilities. The system stability is guaranteed under the most uncertain condition and it was found that the water supply system with uncertainty can be a useful tool to assist decision makers to develop future water supply schemes.
99

Etude et modélisation dynamique de l’élimination de micropolluants prioritaires et émergents au sein du procédé à boues activées / Fate and dynamic modelling of priority and emerging micropollutants in activated sludge process

Pomies, Maxime 16 May 2013 (has links)
Les rejets de station d'épuration (STEP) sont considérés comme un vecteur majeur d'entrée des micropolluants dans les milieux aquatiques. Certains micropolluants, fortement présents dans les eaux à traiter ou trop faiblement éliminés par les filières de traitement, sont ainsi retrouvés dans les eaux usées traitées à des concentrations pouvant atteindre plusieurs centaines de ng/L. Ce travail de recherche vise à identifier et simuler les processus d'élimination de micropolluants au sein du procédé à boues activées en aération prolongée, procédé le plus couramment utilisé en France. Nous nous sommes intéressés à 53 micropolluants, dont l'élimination de la file eau par le procédé à boues activées n'est que partielle (rendement compris entre 30 et 70 % selon AMPERES). Cinq familles de substances aux propriétés physico-chimiques différentes ont ainsi été étudiées : 11 métaux, 14 composés pharmaceutiques, 19 hydrocarbures aromatiques polycycliques, 5 alkylphénols, 4 pesticides. L'objectif de la démarche expérimentale proposée a consisté à identifier et caractériser les principaux mécanismes d'élimination. Ces mécanismes ont été étudiés à deux échelles d'observation, échelle industrielle (STEP vraie grandeur) et une échelle pilote. Le suivi d'un procédé boues à activées au sein d'une STEP (2900 EH) a permis de réaliser 8 bilans matières (file eau et file globale) répartis sur une année. Nous avons ainsi mesuré les variations de concentrations des micropolluants ciblés dans les eaux usées brutes, les eaux usées traitées et les boues, ainsi que les variations de performances d'élimination suivant les conditions de fonctionnement de la STEP (température, durée de présence d'oxygène, taux de MES). Les essais à l'échelle pilote en réacteur fermé ont permis de déterminer les coefficients de sorption et les constantes cinétiques de biodégradation de ces micropolluants en conditions contrôlées. La biodégradation de ces micropolluants a été évaluée pour différentes conditions opératoires relatives aux conditions rédox (aérobie et anoxie) et à différentes conditions de substrat (absence de substrat biodégradable, présence de substrat biodégradable carboné et azoté, présence de substrat azoté seulement). Un modèle dynamique calé est proposé, décrivant le comportement des micropolluants dans les phases dissoute et particulaire. Le paramétrage est obtenu à partir des données expérimentales, à savoir les coefficients de sorption et de biodégradation déterminés en réacteur fermé et des performances d'élimination mesurées pour la STEP. / Discharges from wastewater treatment plants (WWTP) are considered as a major input of micropollutants in the aquatic environment. Some micropollutants are found in treated wastewater at concentrations of several hundred ng/L, due to their high concentration in the raw wastewater or to their low removal by WWTP. This work proposes to model the fate of micropollutants in the activated sludge with extended aeration process, most commonly used in France. We investigated 53 micropollutants, particularly those partially removed from the water line by activated sludge process (between 30 and 70% according to the AMPERES project). Five families of substances with different physicochemical properties were studied: 11 metals, 14 pharmaceutical compounds, 19 polycyclic aromatic hydrocarbons, 5 alkylphenols and 4 pesticides. The objective of the experimental strategy is to characterize the two main removal mechanisms: sorption and biodegradation. It combines a study of a process at WWTP scale and tests at laboratory scale. We have monitored an activated sludge process to achieve eight mass balances (water line and global line) for a year. We have characterized variations of concentration in raw wastewater, treated wastewater and sludge as well as variations in removal efficiency depending on operating conditions. Laboratory scale tests were used to determine sorption coefficients and kinetic biodegradation constants of micropollutants in monitored conditions. We evaluated biodegradation kinetics in different redox conditions (aerobic and anoxic) and different substrate conditions (absence of biodegradable substrate, presence of biodegradable substrate carbon and nitrogen, presence of substrate nitrogen only). The model describing the fate of dissolved and particulate phases is calibrated from sorption and biodegradation constants and removal efficiencies observed for the activated sludge process at WWTP scale.
100

Investigation of biochemical methane potential in Thái Nguyên city and Sông Công city in Vietnam

Deo, Anurag, Axelsson Bjerg, Mette January 2017 (has links)
Currently Vietnam is facing several problems with waste handling. For instance, a lot of the municipal organic solid waste is dumped at landfills, which contributes to environmental difficulties such as greenhouse gas emissions. Anaerobic digestion has proven to be an adequate method for solving environmental problems such as waste treatment, where biogas can be produced. The methane content in the biogas can subsequently be used as a prosperous energy source for heating, electricity and vehicle fuel. The production and utilization of biogas in Vietnam is in a developing face. However, there are issues that should be tackled to improve and expand the biogas production and use. In Vietnam the main substrate used for anaerobic digestion is animal manure as most of the biogas digesters are placed on farms. The purpose of this master thesis was to identify additional potential substrates for biogas production, with focus on Thái Nguyên city and Sông Công city in the Thái Nguyên province. In order to find suitable substrates, interviews and literature research were carried out in Vietnam. Subsequently biochemical methane potential (BMP) tests were performed for the identified and acquired substrates. The BMP-tests were first performed at Thái Nguyên University but as the results were inconclusive, further experiments were performed at Linköping University (Sweden) where eight substrates from the Thái Nguyên province were investigated. The identified substrates used for the BMP-tests were three types of beer waste from the Vicoba brewery in Thái Nguyên city, food waste from different restaurants in Sông Công city, fruit waste from the fruit market in Thái Nguyên and household vegetable waste. The highest methane yield could be observed for household vegetable waste (543 Nml/g VS) followed by beer waste (yeast) with a methane potential of 497 Nml/g VS. Beer waste (hops boiling) had the lowest methane potential with a value of 230 Nml/g VS. Estimation of the total methane potential in both cities together from food waste from restaurants, beer waste and sewage sludge from the upcoming waste water treatment plant (WWTP) in Thái Nguyen city were made by combining data from interviews, literature values and the BMP-results. The estimation showed that from Thái Nguyên City and Sông Công city about 137,500 m3 CH4/year can be produced from food waste from restaurants, about 1.7 millionCH4 m3/year can be produced from sludge from the WWTP in Thái Nguyên city (under construction) and there is also a possibility to produce about 10,700 m3 CH4/year from the beer brewery in Thái Nguyên city. Thus, the total estimated methane potential sums up to 1.8 million m3 CH4/year. The results show that Thái Nguyên city and Sông Công city have potential wastes that preferably could be used as substrates for biogas production which could add on to the biogas produced currently at farm level in the Thái Nguyên region. / I dagsläget står Vietnam inför svåra problem med rådande avfallshantering. En stor del av det organiska avfallet deponeras. Detta bidrar till miljöproblem som exempelvis utsläpp av växthusgaser. Kontrollerad rötning har visat sig vara en bra metod för avfallshantering av organiskt avfall, eftersom biogasen som produceras exempelvis kan användas som energikälla för matlagning, elektricitet och fordonsbränsle, samtidigt som avfallsmängden kraftigt reduceras. Utvecklingen av kommersiell biogasproduktion i Vietnam är fortfarande i ett inledande stadie. De främsta substraten för biogassubstratet som används i landet i nuläget är olika typer av gödsel med anledning av att de flesta rötkammare är placerade på bondgårdar. Syftet med denna studie är att undersöka kompletterande potentiella substrat som kan användas för biogasproduktion i städerna Thái Nguyên och Sông Công som är belägna i provinsen Thái Nguyên. För att identifiera möjliga biogassubstrat genomfördes intervjuer på plats tillsammans med litteraturundersökningar. Vidare genomfördes metanpotentialbestämningar (BMP) för identifierade, utvalda och, erhållna substrat. Det visade sig ej vara möjligt inom tidsramen för besöket att genomföra BMP-testerna på ett fullgott sätt vid Thái Nguyêns universitet med anledning av begränsningar i metodförutsättningar, varför BMP-tester även genomfördes på Linköpings universitet. Totalt testades metanpotentialen för åtta olika substrat från städerna Thái Nguyên och Sông Công. De identifierade substraten som användes i BMP-studien var tre typer av bryggeriavfall från Vicoba bryggeri i Thái Nguyên, matavfall från olika restauranger i Sông Công, fruktavfall från fruktmarknaden i Thái Nguyên och hushållsavfall från ett hushåll i Thái Nguyên. Det högsta metanutbytet kunde observeras för matavfall från hushåll (543 Nml/g VS) följt av bryggeriavfall i form av jäst (497 Nml/g VS). Ölavfall från vörtkokning påvisade det lägsta metanutbytet av samtliga testade substrat motsvarande 230 Nml/g VS. En uppskattning av den totala metanpotentialen i de båda städerna från matavfall från restauranger, bryggeriavfall samt avloppsslam från reningsverket som är under uppbyggnad i Thái Nguyên genomfördes baserat på intervjuer, litteraturvärden samt genomförda metanpotentialtester (BMP). Uppskattningen visade att cirka 137 500 m3 CH4/år skulle kunna produceras från matavfall från restauranger, cirka 1,7 miljoner CH4 m3/år från avloppsreningsverksslam samt från ölbryggeriet i Thái Nguyên är det möjligt att producera cirka 10 700 CH4 m3/år. Sammantaget indikerar det en uppskattad metanpotential motsvarande ca 1,8 miljoner CH4 m3/år. Slutsatsen av den här studien visar att det finns stor potential för biogasproduktion i Thái Nguyên och Sông Công. / Developing strategies and methods for participatory planning in Thái Nguyên and Linköping

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