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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.
281

Санација и заштита великог Бачког канала као услов одрживог коришћења његових развојних потенцијала / Sanacija i zaštita velikog Bačkog kanala kao uslov održivog korišćenja njegovih razvojnih potencijala / Remediation and protection of Veliki backi canal as a prerequisite for sustainable use of its development potential

Pantelić Milana 22 June 2012 (has links)
<p>Тема докторске дисертације је анализа квалитета воде Великог бачког канала, могућности санације и одрживо коришћење његових развојних потенцијала на каналској мрежи и њеном непосредном приобаљу. На основу расположивих података за десетогодишњи период (2000-2009) указало се на проблеме изазване одређеним загађивачима на целој дужини тока и анализиран је утицај најзначајнијих загађивача у насељима која се налазе у непосредној близини канала. Подаци који указују на квалитативну анализу воде помогли су да се направи корелација између квалитета каналске воде и ставова локалног становништва у погледу коришћења Великог бачког канала у привредне сврхе. Циљ дисертације је да дефинише квалитет каналске воде коришћењем хидролошких и статистичких метода који се тренутно широко примењују у многим истраживањима, као и да укаже који од метода дају најбоље резултате. У циљу добијања неопходних резултата, коришћено је више метода, као што су: Serbian Water Quality Index (SWQI), применa hi-квадрат теста, дескриптивна статистичка анализа, t-тест за независне узорке, једнофакторска анализа варијансе АNOVA и израчунавања коефицијента корелације. На основу статистичке обраде података видимо да на читавом току Великог бачког канала, који је дуг свега 123 km постоје деонице (профили I, II и III) које су чисте и у потпуности погодне за експлоатацију и одрживо коришћење свих његових функција, и деоница (профил IV) која је у потпуности деградирана и неупотребљива. На каналу је карактеристично органско загађење. Најзначајнији индустријски објекти лоцирани су у централном делу Великог бачког канала, где је и евидентирано највеће загађење, у општини Врбас. Фарма свиња &bdquo;Farmakoop&ldquo;, фабрика уља &bdquo;Витал&ldquo;, и кланица &bdquo;Carnex&ldquo;, су вруће тачке које су углавном одговорне за лошу еколошку ситуацију у каналу. На простору око Великог бачког канала мали је број фабрика које примењују еколошке стандарде, а само неке од њих имају примарна или секундарна постројења за претходну обраду отпадних вода пре испуштања у реципијент. Резултати SWQI анализе показали су да су деонице на профилима I, II, III и V у потпуности погодне за привредни развој (SWQI&gt;70) а да је деоница на профилу IV (SWQI&lt;37) у потпуности деградирана. Као идеално решење за смањење загађења Великог бачког канала наводи се изградња и употреба централног постројења за прераду отпадних вода, као и коришћење отпадних индустријских и комуналних вода у пољопривреди. На основу резултата анкетног истраживања видимо да локално становништво сматра да Велики бачки канал може да поврати већи део својих ранијих функција (наводњавање, одводњавање, пловидба, узгој рибе...). Да би се то и десило неопходно је контролисати места улива отпадних вода у Канал, а саме отпадне воде третирати и довести у стање у ком неће угрозити његов квалитет воде. Одговори испитаника се разликују у зависности од њиховог места становања, где се посебно истичу становници Врбаса са изузетно негативним ставовима, што је и за очекивати с обзиром на резултате квалитета воде на овом делу Канала.[</p> / <p>Tema doktorske disertacije je analiza kvaliteta vode Velikog bačkog kanala, mogućnosti sanacije i održivo korišćenje njegovih razvojnih potencijala na kanalskoj mreži i njenom neposrednom priobalju. Na osnovu raspoloživih podataka za desetogodišnji period (2000-2009) ukazalo se na probleme izazvane određenim zagađivačima na celoj dužini toka i analiziran je uticaj najznačajnijih zagađivača u naseljima koja se nalaze u neposrednoj blizini kanala. Podaci koji ukazuju na kvalitativnu analizu vode pomogli su da se napravi korelacija između kvaliteta kanalske vode i stavova lokalnog stanovništva u pogledu korišćenja Velikog bačkog kanala u privredne svrhe. Cilj disertacije je da definiše kvalitet kanalske vode korišćenjem hidroloških i statističkih metoda koji se trenutno široko primenjuju u mnogim istraživanjima, kao i da ukaže koji od metoda daju najbolje rezultate. U cilju dobijanja neophodnih rezultata, korišćeno je više metoda, kao što su: Serbian Water Quality Index (SWQI), primena hi-kvadrat testa, deskriptivna statistička analiza, t-test za nezavisne uzorke, jednofaktorska analiza varijanse ANOVA i izračunavanja koeficijenta korelacije. Na osnovu statističke obrade podataka vidimo da na čitavom toku Velikog bačkog kanala, koji je dug svega 123 km postoje deonice (profili I, II i III) koje su čiste i u potpunosti pogodne za eksploataciju i održivo korišćenje svih njegovih funkcija, i deonica (profil IV) koja je u potpunosti degradirana i neupotrebljiva. Na kanalu je karakteristično organsko zagađenje. Najznačajniji industrijski objekti locirani su u centralnom delu Velikog bačkog kanala, gde je i evidentirano najveće zagađenje, u opštini Vrbas. Farma svinja &bdquo;Farmakoop&ldquo;, fabrika ulja &bdquo;Vital&ldquo;, i klanica &bdquo;Carnex&ldquo;, su vruće tačke koje su uglavnom odgovorne za lošu ekološku situaciju u kanalu. Na prostoru oko Velikog bačkog kanala mali je broj fabrika koje primenjuju ekološke standarde, a samo neke od njih imaju primarna ili sekundarna postrojenja za prethodnu obradu otpadnih voda pre ispuštanja u recipijent. Rezultati SWQI analize pokazali su da su deonice na profilima I, II, III i V u potpunosti pogodne za privredni razvoj (SWQI&gt;70) a da je deonica na profilu IV (SWQI&lt;37) u potpunosti degradirana. Kao idealno rešenje za smanjenje zagađenja Velikog bačkog kanala navodi se izgradnja i upotreba centralnog postrojenja za preradu otpadnih voda, kao i korišćenje otpadnih industrijskih i komunalnih voda u poljoprivredi. Na osnovu rezultata anketnog istraživanja vidimo da lokalno stanovništvo smatra da Veliki bački kanal može da povrati veći deo svojih ranijih funkcija (navodnjavanje, odvodnjavanje, plovidba, uzgoj ribe...). Da bi se to i desilo neophodno je kontrolisati mesta uliva otpadnih voda u Kanal, a same otpadne vode tretirati i dovesti u stanje u kom neće ugroziti njegov kvalitet vode. Odgovori ispitanika se razlikuju u zavisnosti od njihovog mesta stanovanja, gde se posebno ističu stanovnici Vrbasa sa izuzetno negativnim stavovima, što je i za očekivati s obzirom na rezultate kvaliteta vode na ovom delu Kanala.[</p> / <p>The topic of this PhD thesis is the quality analysis of the Veliki Backi Canal water, possible recovery and sustainable use of its development potential over the canal network and its immediate banks area. Based on the relevant data for a ten-year period (2000-2009) certain problems surfaced caused by various polluters throughout the entire canal and the impact of the most significant polluters on populated areas in the vicinity of the canal has been analysed. Data gathered with qualitative analyses of water helped in establishing the correlation between the quality of canal water and local population attitude towards the use of the Veliki Backi Canal for commercial purposes. The purpose of this thesis is to define the quality of canal water using hydrologic and statistic methods, currently widely used in numerous researches, as well as to pinpoint which method provides the best results. In order to obtain the necessary data various methods were used: Serbian Water Quality Index (SWQI), application of hi-square test, descriptive statistic analysis, t-test for independent samples, one-factor analyses of variance АNOVA and the correlation coefficient measurement. Based on statistical data it can be observed that there are different sections of the entire Veliki Backi Canal, only 123 km in length. There are sections (profiles I, II and III) which are clean and fully appropriate for exploitation and sustainable use of all its functions. However, there is also a section (profile IV) which is completely degraded and unusable. Another characteristic of the Canal is organic pollution. The biggest industrial facilities are based in the central part of the Veliki Backi Canal with highest pollution in the municiplaity Vrbas. There are hot spots, such as a pig farm &bdquo;Farmakoop&ldquo;,oil factory &ldquo;Vital&rdquo; and slaughterhouse &bdquo;Carnex&ldquo;, mainly responsible for poor ecological state of the Canal. An insignificant number of factories in the area of the Veliki Backi Canal apply ecology standards and only few have primary or secondary facilities for pre-treatment of waste water before discharge into the recipient. SWQI analyses results show that the Canal sections with profiles I, II, III and V are entirely appropriate for economic development (SWQI&gt;70) whereas the section with profile IV (SWQI&lt;37) is completely degraded. In order to decrease pollution of the Veliki Backi Canal, as the ideal solution is suggested to construct the central facility for pre-treatment of wastewater as well as to use industrial and utility wastewater in agriculture. According to the survey results the locals believe that the Veliki Backi Canal could recover most of its previous functions (irrigation, drainage, sailing, fish farming....). In order to ensure something like that it would be necessary to control wastewater flow spots and to treat the wastewater so that it does not endanger the water quality of the Canal. The survey responses differ according to the area of living with particularly negative attitudes of people from Vrbas and that was to be expected if we bear in mind the worst water quality results in this part of the Canal.</p>
282

Využití odpadní vody v EDU pro vytápění / Use of Waste Water in Nuclear Power Dukovany for Heating

Bohůn, Vojtěch January 2010 (has links)
This diploma thesis deals with various ways of energetically advantageous utilization of waste heat produced by industrial technologies. The focus of the diploma thesis is both to provide an overview of different ways and places of origin of waste heat in industrial technologies and of its possible reutilization, to suggest a concrete air heating system using waste heat and to propose a long-distance hot water pipe which supplies hot water pipe system with energy. First, technologies producing waste heat and some ways of regressing of heat in such technologies are theoretically described. Second, the equipment for transferring of heat and for adjustment of thermal energy parameters is described. A special focus is put on water supplies of the Nuclear Power Plant Dukovany and some selected parts of its secondary circuit, which is waste heat collected from. The analysis is supplemented by a calculation of theoretical quantity of waste heat. The aim of the calculation is to determine whether waste heat can be a source of energy for heating. Then, a current system of heating of three selected buildings in the area of the Nuclear Power Plant Dukovany is briefly described. Based on the gained knowledge, a project of air heating with two heat pumps type water – water, a heat receiver preparing warm service water and three recuperative units for preheating of fresh heating air is designed. The selection of main parts of the air heating is amended by a calculation of purchase costs and electric energy consumption. After that, the focus is placed on choice of type of hot water pipe – its trace is stated and an indicative estimation and a thermal-conditions calculation in the hot water pipe are made. The preliminary calculation serves as a source of information for a final project of air heating and calculation of changes of temperatures longwise the hot water pipe. The project contains also a calculation of pressure losses and an analysis of economical questions concerning hot water pipes. In conclusion, the results of project of air heating and hot water pipes are summarized.
283

Zdravotně technické instalace ve studentských kolejích / Sanitation installation in student dormitories

Kucharik, Miroslav January 2015 (has links)
Diploma thesis describes the design of plumbing systems in student dormitories. The theoretical part discusses the types of waste water, focusing on gray water and its subsequent use. The experimental part is focused on measurement drinking water consumption and drinking water discharge in existing buildings student dormitories and apartment building. The work also contains other variants of possible installation solutions. The project is part of the selected solutions developed a variant form of project documentation for construction.
284

Provoz a řízení sprchových rekuperačních výmeníků / Operation and management of shower heat recovery exchanger

Veselská, Monika January 2015 (has links)
This thesis deals with the operation and management of shower recuperative heat exchangers, energy recovery from them and further use of this energy. This work is divided into four parts. The first presents the possibilities of using energy from wastewater. The second part deals with the design possibilities of energy recovery from waste water in the building, design water and sewer . The third part is devoted to the specification of the shower regenerative heat exchanger, its operation, regulation and control, culminating in economic evaluation of the proposed exchanger. The last part is a technical report and annexes drawings of the project.
285

Zajištění náhradního způsobu odvodů odpadu obklíčené nemovité věci v cizím areálu / Provision of alternative refuse collection for a real estate surrounded by foreign property

Kvapil, Radek January 2016 (has links)
The thesis deals with possible ways of drainage and wastewater disposal. The issue of wastewater discharge to the environment has been closely monitored in recent years, and there is an apparent effort to improve the current situation.The dissertation discusses and compares three selected options – access to improved sanitation, building reservoirs and domestic wastewater treatment plant.The final section is dedicated to a comparison of acquisition and operating costs over time and to subsequent evaluation of the most suitable option. For the sake of clarity and assessment of potential solutions, the locality in the administrative area Vysoké Mýto - Domoradice has been selected as a model. The local authorities have been designing a public storm sewer, and given that it is surrounded by land, this issue will need to be addressed.
286

Kostenbewertung der Anpassung zentraler Abwasserentsorgungssysteme bei Bevölkerungsrückgang

Schiller, Georg 23 September 2014 (has links)
Rückläufige Bevölkerungszahlen und Siedlungsflächenwachstum führen zu steigenden Kosten für leitungsgebundene Infrastrukturen. Dies gilt besonders für die Abwasserentsorgung, die in Deutschland überwiegend über die öffentliche Kanalisation erfolgt. Bei Neuerschließung können im Falle geringer Siedlungsdichten dezentrale Abwassersysteme Kostenvorteile gegenüber zentralen Systemen aufweisen. Lassen sich aber durch Dezentralisierung auch Kosten im bereits erschlossenen, von Schrumpfung betroffenen, Siedlungsbestand reduzieren? Um hierauf Antworten zu geben, werden Kosten der Transformation zentraler Abwassersysteme hin zu stärker dezentral angelegten Strukturen berechnet. Am Beispiel eines realen Abwasser-Entsorgungsgebietes wird ein Verfahren entwickelt, das eine Kostenbewertung der schrittweisen Dezentralisierung technischer Abwassersysteme ermöglicht.:Zusammenfassung............................................................................... 13 Summary............................................................................................... 15 Kurzfassung.......................................................................................... 17 1 Einführung......................................................................................... 27 A Grundlagen........................................................................................ 45 2 Abwasserentsorgung – Begriffe und Strukturdaten.......................... 45 3 Zentral oder Dezentral...................................................................... 53 4 Kostenwirkungen des Nachfragerückgangs im System der zentralen Abwasserentsorgung........................................................... 61 B Entwicklung des Bewertungsverfahrens............................................ 71 5 Untersuchungsgebiet........................................................................ 71 6 Siedlungsmodell................................................................................. 75 7 Infrastrukturmodell.......................................................................... 107 8 Bezugsmodell................................................................................. 123 9 Sequenzanalyse.............................................................................. 137 10 Kostenmodell................................................................................. 151 C Modellrechnungen........................................................................... 171 11 Zukunftsprojektion Siedlungsmodell.............................................. 171 12 Kostenrechnung............................................................................ 179 D Interpretation und Ergebnisse........................................................ 203 13 Auswertung und Interpretation..................................................... 203 14 Ergebnisse und Fazit..................................................................... 221 15 Forschungs- und Entwicklungsbedarf............................................ 231 Literatur...............................................................................................235 Abbildungsverzeichnis........................................................................ 247 Tabellenverzeichnis............................................................................ 251 Anlage Kostenkennwerte................................................................... 253 / Declining populations and an expansion in settlement areas have led to a rise in the cost of pipeline networks for household supply and waste removal. This is particularly true of waste-water removal, which in Germany is primarily managed using public sewage systems. The work at hand tries to give answer to the question, if decentralisation can lower costs in the building stock affected by shrinkage, which is already connected to the waste-water network.:Zusammenfassung............................................................................... 13 Summary............................................................................................... 15 Kurzfassung.......................................................................................... 17 1 Einführung......................................................................................... 27 A Grundlagen........................................................................................ 45 2 Abwasserentsorgung – Begriffe und Strukturdaten.......................... 45 3 Zentral oder Dezentral...................................................................... 53 4 Kostenwirkungen des Nachfragerückgangs im System der zentralen Abwasserentsorgung........................................................... 61 B Entwicklung des Bewertungsverfahrens............................................ 71 5 Untersuchungsgebiet........................................................................ 71 6 Siedlungsmodell................................................................................. 75 7 Infrastrukturmodell.......................................................................... 107 8 Bezugsmodell................................................................................. 123 9 Sequenzanalyse.............................................................................. 137 10 Kostenmodell................................................................................. 151 C Modellrechnungen........................................................................... 171 11 Zukunftsprojektion Siedlungsmodell.............................................. 171 12 Kostenrechnung............................................................................ 179 D Interpretation und Ergebnisse........................................................ 203 13 Auswertung und Interpretation..................................................... 203 14 Ergebnisse und Fazit..................................................................... 221 15 Forschungs- und Entwicklungsbedarf............................................ 231 Literatur...............................................................................................235 Abbildungsverzeichnis........................................................................ 247 Tabellenverzeichnis............................................................................ 251 Anlage Kostenkennwerte................................................................... 253
287

Grundwasseranreicherung unter den geologischen, hydrochemischen und geografischen Bedingungen des Distrito Federal, Brasilien

Gaffron, Anne 24 September 2014 (has links)
The Distrito Federal in Western Central Brazil is characterized by a high share of urban population and a predicted growth of population. The corresponding increasing water consumption is associated with a falling groundwater table. The existing wastewater treatment plants could reach their capacity limits due to further increasing amounts of urban wastewater in conjunction with heavy precipitation events. During these events, untreated wastewater can become a contamination source for protected resources such as soil and water. This problem can be solved by soil aquifer recharge. This is a unique technique to take the load off the treatment plants, to store the water in the aquifer, and to improve the water quality during the soil passage. The controlled infiltration of pretreated municipal wastewater in the tropical soils can ensure the regional groundwater balance and backup high quality water as a suitable drinking water resource. The objective of the present thesis was to define suitable soils and areas for a soil aquifer treatment in the Distrito Federal to support the decentralized wastewater treatment management. For the identification of suitable soils, representative samples were taken. The soil samples were examined with respect to their pedological and geochemical properties. For the characterization of the unsaturated hydraulic conditions, in situ infiltration tests and a 3D infiltration monitoring were performed. Additionally, the retention potentials for sewage ingredients were determined for each soil with unsaturated, hydrochemical and geoelectrical column tests. Thus, it was possible to calculate the retention potentials of each soil against the wastewater content of an artificial wastewater. The artificial wastewater with known composition was infiltrated through the soil columns. The retention potentials of the soils were calculated by balancing the hydrochemical data. Afterwards, for the implementation of the hydraulic data and the data from the column tests, a utility analysis was performed to merge all parameters. Finally, the field and laboratory studies were combined within a GIS-based usability analysis to blend the determined parameter with geo-data to identify suitable areas for a soil aquifer treatment. Parameters as slope, land use and land cover were included in this analysis. After the evaluation of the hydrochemical balances, predominantly the younger soils turn out as suitable for an artificial recharge with water of impaired quality because of their high retention potential for TOC. The Gleissolo featured a retention potential of almost 100 % for TOC. However, a high hydraulic conductivity in the soils is necessary to ensure an effective artificial recharge. The Gleissolo featured the lowest measured hydraulic conductivity in the field test with 1,12 x 10-8 m/s. Due to the consideration of the determined hydraulic and hydrochemical data in the utility analysis, each parameter was weighted to embrace the requirement of an effective artificial recharge. The results of the laboratory and field tests have shown that the soil group of Latossolos is suitable for a soil aquifer treatment. These soils offer the best infiltration characteristics and a good retention potential against sewage ingredients for an effective artificial groundwater recharge with pretreated wastewater. Additional to that, slope, land use/land cover, depth of soil, and a defined distance to conservation area were considered in a GIS-based usability analysis. Additionally, the categorized soils from the utility analysis were included to identify suitable regions. The outcome of the thesis is a GIS-based usability analysis map which shows suitable areas for a soil aquifer treatment ranked by their category of suitability. Additionally, the thesis provides crucial evidences for soil parameters which have positive effects on wastewater infiltration. In addition, the 3D infiltration monitoring and the measured resistivity distribution showed that the gravitatively controlled infiltration influences only the soil zone immediately beneath the irrigation. Furthermore, it was found that the proxy of the geoelectrical resistivity is not (sufficiently) conclusive for the sorption potential of conductive wastewater ingredients. / O Distrito Federal, localizado no Centro-Oeste Brasileiro, é caracterizado por um intenso processo de urbanização o qual deve aumentar ainda mais nas próximas décadas. O correspondente crescimento no consumo de água está, também, associado ao rebaixamento dos níveis das águas subterrâneas. O atual sistema de tratamento de efluentes pode atingir seu limite de operação diante do crescimento demográfico e aumento de eventos extremos de chuva. Durante esses eventos, efluentes não tratados podem tornar-se uma fonte de contaminação aos recursos hídricos e solos. Uma solução é recarga artificial de águas subterrâneas. A mesma armazena o efluente pré-tratado nas águas subterrâneas e melhora a qualidade do mesmo durante o processo de percolação no solo. A infiltração controlada em solos tropicais pode contribuir para a qualidade das águas subterrâneas e balanço hídrico, servindo assim como fonte para o abastecimento de água. Essa tese tem como objetivo a identificação de áreas e solos propícios à recarga artificial de águas subterrâneas no Distrito Federal a fim de dar suporte à gestão decentralizada de tratamento de efluentes. Para a identificação dessas áreas, amostras representativas à diferentes tipos de solos foram obtidas. As amostras foram examinadas de acordo com suas propriedades pedológicas e geoquímicas. Para a caracterização das condições hidráulicas não saturadas, realizaram-se diversos testes de infiltração in situ, bem como o monitoramento 3D. Ainda, determinou-se para cada solo o potencial de retenção de poluentes através de testes de coluna insaturados, hidroquímico e geoelétricos. Dessa forma foi possível calcular os potenciais de retenção para cada solo quando utilizados efluentes sintéticos. Com base na contabilização de todos os dados hidroquímicos, calculou-se os potenciais de retenção de poluentes para o determinado efluente de composição conhecida. Mais a frente, para a implementação de dados hidráulicos e dados dos testes de coluna, utilizou-se uma análise de utilidade considerando todos os parâmetros. Finalmente, estudos de laboratório e campo foram combinados em uma análise baseada em sistema de informação geográfica (SIG). O mesmo permite o cruzamento de um determinado parâmetro obtido com uma base de dados georeferenciados (p. ex. classes de solos) a fim de identificar as áreas mais propícias. Parâmetros tais como declividade, uso e cobertura de solo foram incluídos nessa análise. Após a avaliação dos balanços hidroquímicos, identificou-se que os solos jovens possuem um alto potencial de retenção de carbono orgânico total (COT). Os mesmos mostraram-se adequados para recarga de águas subterrâneas com efluente residuário pré-tratado. Como exemplo, o Gleisolo apresentou um potencial de retenção de aproximadamente 100% de COT. No entanto, é importante lembrar que, a fim de garantir uma retenção efetiva, a condutividade hidráulica do solo deve ser alta. Nesse caso, o Gleisolo apresentou baixos valores no teste de campo com uma condutividade hidráulica de 1,12 x 10-8 m/s. Ainda, os dados hidráulicos e hidroquímicos medidos foram integrados à uma análise de uso-benefício. No caso, cada parâmetro recebe um peso de modo a atender às demandas de uma recarga efetiva de águas subterrâneas. Resultados mostram que o grupo de solo classificado com Latossolo é propício para a recarga de águas subterrâneas. O mesmo oferece a melhor característica de infiltração e potencial de retenção de contaminantes para uma recarga artificial com efluentes pré-tratados. Declividade, uso e ocupação de solo, profundidade do solo e uma distância devida de áreas de conservação foram contemplados na análise de utilidade baseada em SIG. Além disso, os colos caracterizados pela análise de uso-benefício foram incluídos com o intuito de identificar as regiões mais propícias para a prática. O resultado da tese é uma representação gráfica georeferenciada das áreas propícias para a aplicação de recarga artificial de águas subterrâneas. Ainda, a tese fornece evidências cruciais de parâmetros do solo que tem efeitos positivos na infiltração de efluentes pré-tratados. O monitoramento 3D de infiltração e a distribuição de resistividade medida mostram que infiltração controlada por gravidade influencia apenas a zona do solo imediata à superfície de irrigação. Mas a frente, foi determinado que o proxy da resistividade geoelétrica não é válido para o potencial de retenção de contaminantes condutores. / Der Distrito Federal ist durch eine starke Urbanisierung geprägt. Das ohnehin bereits starke Bevölkerungswachstum wird Prognosen zufolge weiter zunehmen. Der damit verbundene Anstieg des Wasserverbrauchs wird auch in absinkenden Grundwasserständen widergespiegelt. Weiterhin ist das westliche Zentralbrasilien aufgrund seiner Lage in den wechselfeuchten Tropen durch eine starke Saisonalität der Niederschläge geprägt. Das erhöhte Abwasseraufkommen in Verbindung mit extremen Niederschlagsereignissen kann zu einer deutlichen Überbelastung der vorhandenen Kläranlagen führen. In Extremsituationen kann ungeklärtes Abwasser in die Bodenzone gelangen und somit Schutzgüter wie Boden und Wasser kontaminieren. Eine effiziente Maßnahme gegenüber der unkontrollierten Versickerung von ungeklärtem Abwasser sowie zur Vorbeugung absinkender Grundwasserspiegel ist die gezielte Infiltration von vorbehandeltem Abwasser in Verbindung mit einer Grundwasseranreicherung. Diese Maßnahme umfasst einen zusätzlichen Reinigungsschritt des vorgereinigten Abwassers und dient zur Vorbeugung gegenüber absinkenden Grundwasserspiegeln. Ziel der Arbeit war es, geeignete Böden und Flächen für eine Grundwasseranreicherung mit vorbehandeltem Abwasser im Distrito Federal auszuweisen. Zur Identifizierung geeigneter Böden wurden repräsentative Bodenproben auf ihre pedologischen und geochemischen Eigenschaften hin untersucht. Zusätzlich wurden in situ Durchlässigkeitstests und ein Versickerungsmonitoring aufgebaut, um zur Klärung der Infiltrationseigenschaften beizutragen. Für die Laboruntersuchungen wurden die Bodenproben im Hinblick auf ihre Schadstoffrückhaltepotentiale untersucht. Dazu wurden kombinierte hydrochemische und geoelektrische sowie ungesättigte Säulenversuche durchgeführt. Dadurch war es möglich, Rückschlüsse auf die Sorptionsleistung der Böden gegenüber den Abwasserinhaltsstoffen einer künstlichen Abwasserlösung schließen zu können. Die Bodensäulen wurden mit einem künstlichen Abwasser mit bekannter Schadstoffzusammensetzung überstaut. Auf der Grundlage der Bilanzierung aller hydrochemischen Daten wurden die Schadstoffrückhaltepotentiale für die Abwasserinhaltsstoffe berechnet. Anschließend wurden die experimentell ermittelten Parameter in einer Nutzwertanalyse zusammengefasst, um so geeignete Böden für eine effiziente Grundwasseranreicherung mit vorbehandeltem Abwasser zu identifizieren. Abschließend wurden die Feld- und Laboruntersuchungen mit einer GIS-basierten Nutzbarkeitsanalyse komplettiert, um die gemessenen Parameter mit weiteren vorliegenden, räumlich aufgelösten Daten verschneiden zu können. In diese Analyse wurden Parameter wie Gefälle, Landnutzung und Landbedeckung einbezogen. Bei der Auswertung der hydrochemischen Bilanzen kristallisierten sich vorwiegend die jungen Böden aufgrund ihrer hohen Schadstoffrückhaltepotentiale als geeignete Böden für eine Grundwasseranreicherung mit vorbehandeltem Abwasser heraus. Exemplarisch wies der Gleissolo ein Sorptionspotential von fast 100 % für den Parameter TOC auf. Allerdings müssen Böden für eine effektive Grundwasseranreicherung mit vorbehandeltem Abwasser zusätzlich zu den hohen Sorptionsleistungen auch hohe hydraulische Durchlässigkeiten aufweisen. Für den Gleissolo wurde im Feldversuch die niedrigste hydraulische Durchlässigkeit von 1,12 x 10-8 m/s bestimmt. Durch die Einbindung der gemessenen hydraulischen und hydrochemischen Daten in eine Nutzwertanalyse konnten diese Parameter gewichtet werden, um so den Ansprüchen einer effektiven Grundwasseranreicherung gerecht zu werden. Im Ergebnis der durchgeführten Untersuchungen hat sich gezeigt, dass sich die Bodengruppe der Latossole besonders gut für eine Grundwasseranreicherung mit vorbehandeltem Abwasser eignet. Diese Böden weisen die besten Infiltrationsbedingungen sowie gute Sorptionseigenschaften für eine effizient gestaltete Grundwasseranreicherung auf. Mit Hilfe der GIS-basierten Nutzbarkeitsanalyse geografischer Parameter wurden Flächen ausgezeichnet, die sich in Bezug auf Gefälle, Landnutzung/Landbedeckung, Bodentiefe und einer adäquaten Distanz zu Schutzgebieten für eine Grundwasseranreicherung mit vorbehandeltem Abwasser eignen. Zusätzlich wurden die mit Hilfe der Nutzwertanalyse kategorisierten Böden in die Flächenidentifizierung einbezogen. Das Resultat dieser Arbeit liegt in Form einer Karte vor, in der die Gebiete, die für eine Grundwasseranreicherung mit vorbehandeltem Abwasser geeignet sind, nach Kategorien geordnet, verzeichnet sind. Zusätzlich dazu liefert die Arbeit entscheidende Hinweise auf Bodeneigenschaften, die sich positiv auf eine Abwasserinfiltration auswirken. Darüber hinaus konnte durch das geoelektrische 3D-Monitoring und der dabei gemessenen Verteilung des spezifischen elektrischen Widerstandes gezeigt werden, dass die Infiltration gravitativ gesteuert nur die Bodenzone direkt unterhalb der Verrieselung beeinflusste. Weiterhin wurde festgestellt, dass das Proxy des geoelektrischen Widerstandes im Labormaßstab nicht aussagekräftig genug ist, um Rückschlüsse auf die Sorption leitfähigkeitsrelevanter Abwasserinhaltsstoffe geben zu können.
288

Nationell potentialbedömning av olika energieffektiviseringsåtgärders kostnadseffektivitet i flerbostadshus : En jämförelse av olika åtgärder och analys av olika styrmedels anpassning för minskad energianvändning / National Potential Assessment Energy Efficiency and Cost-effectiveness in Multi-family Buildings : A comparison of energy efficiency measures and the conformation of Different Policy Instrument for reduced energy use

Jansson, Josef, Enell, Elisabeth January 2022 (has links)
Energianvändningen idag är den största bidragande faktorn till de globala klimatförändringarna vilket ställer krav på mer hållbar och resurseffektiv energihantering. I Sverige står sektorn bostäder och service för ca 40 % av den slutgiltiga energianvändningen motsvarande 144 TWh. För att nå en mer hållbar byggnadssektor har EU i direktivet för Byggnaders Energiprestanda satt målet att byggnadssektorn ska vara fossilfri till 2050, samt beslutat att varje medlemsstat ska etablera en långsiktig renoveringsstrategi. Nationellt finns därmed målet att minska den totala energianvändningen per uppvärmd area med 50 % till 2050 jämfört med 1995. Detta innebär att omfattande energieffektiviseringsåtgärder (EEÅ) behöver implementeras i Sveriges byggnadsbestånd. I examensarbetet jämförs den nationella potentialen avseende energibesparing, kostnadseffektivitet samt utsläppsreduktion av koldioxidekvivalenter (CO2eq) för olika energieffektiviseringsåtgärder (EEÅ) kopplade till uppvärmning och tappvarmvattenanvändning i flerbostadshus. Vidare undersöks även hur väl anpassade befintliga styrmedel är för de studerade EEÅ. För att besvara frågeställningarna har sex olika typhus tagits fram vilka är representativa för Sveriges bestånd av flerbostadshus. Dessa byggnader har modellerats i programvaran IDA ICE och energisimuleringar har genomförts för att undersöka effekterna av samtliga EEÅ. Vidare, styrmedel kopplade till energieffektivisering av flerbostadshus har analyserats och dess innebörd för olika EEÅ granskats. Resultatet visar att inom det svenska flerbostadshusbeståndet har installation av spillvattenvärmeåtervinning och FTX störst tekniskt möjlig energibesparingspotential med en årlig nationell energibesparingspotential på 5,3 TWh respektive 4,7 TWh. Isolering av tak är den EEÅ med högst kostnadseffektivitet per sparad energienhet, 334–579 SEK/MWh beroende på klimatzon, följt av spillvattenvärmeåtervinning och FTX som har en kostnadseffektivitet på 1267–1503 SEK/MWh respektive 1882–3587 SEK/MWh. Takisolering är även den EEÅ som är mest kostnadseffektiv för utsläppsminskning av koldioxidekvivalenter följt av spillvattenvärmeåtervinning och FTX. För takisolering är kostnadseffektiviteten 5,9–10,3 tSEK/ton CO2eq, 28,2–33,5 tSEK/ton CO2eq för spillvattenvärmeåtervinning och 39,5–93 tSEK/ton CO2eq för installation av FTX. Utifrån de styrmedel som studerats konstateras det att befintliga styrmedel för energieffektivisering i flerbostadshus inkluderar konventionella EEÅ men att det finns bristfällig information och krav gällande återvinning av värme från spillvatten trots åtgärdens höga energibesparingspotential och kostnadseffektivitet. Bättre kunskap och information gällande kostnadseffektiviteten för olika EEÅ kan leda till mer resurseffektiva åtgärdsförslag från energiexperter och även öka renoveringstakten. / Today's energy use is the largest contributing factor to global climate change, which calls for a more sustainable and resource-efficient energy management. In Sweden, the residential and service sector accounts for about 40% of the final energy use, corresponding to 144 TWh. To achieve a more sustainable building sector, the European Commission has set a target in the Energy Efficiency Directive that the building sector should be fossil-free by 2050 and decided that every Member State should establish a long-term renovation strategy. Nationally, there is a target to reduce the total energy use per heated area by 50% by 2050. This requires a large-scale implementation of energy efficiency measures (EEMs) in Sweden's building stock. This master thesis compares the national potential regarding energy saving, cost-effectiveness and emission reduction of carbon dioxide equivalents (CO2eq) for various EEMs linked to heating and domestic hot water use in multi-family buildings. Furthermore, it is also examined how well-adjusted existing policy instruments are to the studied EEMs. To answer the research questions, six different reference buildings, which are representative of Sweden’s stock of multi-family buildings, have been developed. These buildings have been modeled using the software IDA ICE and energy simulations have been carried out to investigate the effects for all EEMs. Policy instruments regarding energy efficiency in multi-family buildings have been analyzed and their significance for various EEMs have been investigated. The results show that installation of wastewater heat recovery and exhaust air heat recovery has the highest technically possible energy saving potential with an annual national saving potential of 5.3 TWh and 4.7 TWh, respectively Roof insulation is the EEM with the highest cost-effectiveness per saved energy unit, 334–579 SEK/MWh depending on climate zone, followed by wastewater heat recovery with a cost-effectiveness of 1267–1503 SEK/MWh and exhaust air heat recovery with 1882–3587 SEK/MWh. Roof insulation is also the EEM that is most cost-effective regarding reduced CO2eq -emissions, followed by wastewater heat recovery and exhaust air heat recovery. For roof insulation, the cost-effectiveness is 5.9–10.3 kSEK/ton CO2eq, 28.2–33.5 kSEK/ton CO2eq for wastewater heat recovery and 39.5–93 kSEK/ton CO2eq for installation of exhaust air heat recovery. Based on the studied policy instruments, it is found that the existing policy instruments for EMMs in multi-family buildings include conventional EMMS. However, there is insufficient information and requirements regarding recovery of heat from wastewater despite the measure's high energy saving potential and cost-effectiveness. Better knowledge and information regarding the cost-effectiveness of various EEMs can lead to more resource-efficient suggestions from energy experts and increase the pace of renovation.
289

Treatment of Spent Pickling Acid from Stainless Steel Production : A review of regeneration technologies with focus on the neutralisation process for implementation in Chinese industry

Dahlgren, Lena January 2010 (has links)
Pickling is a unit operation within stainless steel production, which means treating the steel with hydrofluoric acid (HF) and nitric acid (HNO3), also called mixed acid. The whole process generates waste water streams which have to be treated before released to recipient. The aim of this degree thesis was to make an evaluation of different possibilities for reduction of emissions from the pickling process with China as a possible future market. The work consisted of two different parts; the first was to describe and evaluate different treatment methods for waste pickling acid, with emphasis on denitrification technologies. The second and main part was to make a fundamental description of the neutralisation process and outline important parameters. The work was performed by gathering information from literature but also from industry in both Sweden and China. The work has been a collaboration between the Royal Institute of Technology (KTH), the Swedish Environmental Institute (IVL) and the company Scanacon. A review of the different acid recovery methods; ionic exchange, diffusion dialysis and extraction was made. The study showed that ionic exchange is a robust method with relatively low cost and therefore it has been largely implemented both in Swedish and Chinese industry. The outflow however still requires neutralisation. Nitrate reduction can be performed as “end of pipe”, those methods investigated in this study were; biological treatment, reverse osmosis and nanofiltration. Meanwhile, internal solutions such as evaporation and electro-dialysis are two interesting technologies which reduce nitrates in combination with acid recovery. It was found that slaked lime (Ca(OH)2) is the most suitable neutralisation agent for pickling waste and, besides the choice of chemicals, many important parameters influence the process, such as the optimal pH, mixing and conditions during lime slaking. Based on information from one of the visited sites in Sweden a mass balance of the neutralisation facility was made and from that the required amount of Ca(OH)2 was calculated. The calculations were verified by an experimental part performed by IVL, using pickling acids from the same site. The amount of metals in the outgoing water was calculated using software “Medusa” but also by equilibrium equations. However, the results differed somewhat; this is probably due to the fact that Medusa takes other complexes and their interaction, besides the formed metal hydroxides, into consideration. Within the mining industry research has been made on different methods for neutralisation and some have been tested in field. An example is the High Density Sludge process (HDS), were an amount of sludge is recycled back to the neutralisation tank. It was shown that this gave improved sludge properties and decreased lime consumption. This could perhaps also be implemented for waste water in the stainless steel industry, and the method was also tested during the experimental part of this project. The dry content increased after a number of cycles but further investigation is required before any conclusion can be drawn. / Betning är en enhetsprocess inom tillverkningen av rostfritt stål då godset behandlas med fluorväte syra (HF) och salpetersyra (HNO3), också kallad blandsyra. Betningen ger upphov till vatten strömmar som måste behandlas innan de släpps ut till recipienten. Syftet med det här examensarbetet var att göra en utvärdering av olika tekniker för att reducera utsläpp till vatten från betningen med Kina som potentiell framtida marknad. Arbetet bestod av två delar; den första delen var att beskriva och utvärdera olika behandlingsmetoder av förbrukade betbad med betoning på denitrifikationstekniker. Den andra och största delen var att göra en grundläggande beskrivning av neutralisationsprocessen. Studien utfördes genom att inhämta information från litteratur samt från industrin i både Sverige och Kina. Arbetet har varit ett samarbetsprojekt mellan Kungliga Tekniska Högskolan (KTH), Svenska miljöinstitutet (IVL) och företaget Scanacon.    Arbetet behandlar syraåtervinningsystemen; jonbytare, diffusions dialys samt extraktion. Nitrat reduktion kan ske internt eller externt där de externa åtgärder som behandlas i denna rapport är biologisk rening, omvänd osmos och nanofiltrering. De interna metoderna avdunstning och elektrodialys är intressanta eftersom de återvinner syran samtidigt som de reducerar nitraterna avsevärt. Studien visade att jonbyte, på grund av dess robusthet och relativt låga kostnad är den mest implementerade metoden för syraåtervinning i både svensk och kinesisk industri idag. Restprodukten från jonbytaren kräver dock fortsatt behandling, där det traditionella valet är neutralisation. Studien visade att släckt kalk (Ca(OH)2) är det mest passande kemikalien för neutralisation av betsyror. Förutom kemikalieval så finns det många parametrar som påverkar effektiviteten hos processen så som pH, omrörning och förhållanden under kalksläckningen. Baserat på information ifrån ett av de besökta stålverken i Sverige, gjordes en massbalans över dess neutralisationanläggning. Utifrån de flöden som denna gav kunde den teoretiska mängden kalk som krävdes för utfällning räknas ut. Beräkningarna verifierades med en experimentell del som utfördes av IVL på betsyror från samma verk. Resthalterna av metall i utgående vatten beräknades med programmet ”Medusa” men också med jämviktsekvationer. Resultaten mellan de två skiljde sig, detta beror förmodligen på att Medusa förutom hydroxidutfällning tar hänsyn till andra utfällningskomplex och dess interaktioner. Inom gruvvatten industrin har det forskats en del kring olika neutralisationsmetoder, en i litteraturen föreslagen sådan är ”High Density Sludge process (HDS)”. Här återförs en del av slammet tillbaka till neutralisationssteget, vilket visade sig ge förbättrade slamegenskaper och minskad kalkåtgång. Det var intressant att undersöka om denna metod också gick att implementera på förbrukade betbad och därför prövades metoden i den experimentella delen av detta projekt. Detta gav efter ett antal återföringscykler högre torrhalt på slammet, dock krävs fortsatta undersökningar innan någon slutsats kan dras.
290

Hydrologische Modellierung urbaner Nährstoffeinträge in Gewässer auf Flussgebietsebene

Biegel, Markus 20 December 2005 (has links)
This thesis describes the conception and implementation of the hydrological model ArcEGMO-URBAN and its application to the basin of the Havel river in north-eastern Germany. The model has been developed in order to make up the balance of nitrogen and phosphorus inputs from point sources in urban areas on the scale of river basins. The nutrient input can be calculated with a high spatial resolution and according to its seasonal variation. At the same time, the impact of the rainfall on the nutrient input is being focused on in this project. ArcEGMO-URBAN models rainfall-runoff processes and pollution-transport processes in urban areas taking natural, technological and social parameters into consideration. Input data are meteorological and terrestrial data with a high spatiotemporal resolution as well as statistic data on the scale of municipalities. The digitally available spatial data are being analysed with GIS functions before the actual modelling and later merged to areas with similar attributes. Technological and social parameters are assigned to these areas which were derived from statistic data. The diversity of the input data and their high spatial resolution allow for the description of relevant processes differentiated on the scale of urban patches. The model considers different urban water technologies and their determined matter fluxes as well as different sewer systems. With regard to rainfall-runoff processes the following sub-processes are considered for this model: the runoff-generation and runoff-concentration on sealed surfaces, the runoff-transformation and combination with the dry weather flow in the sewer system, and the split-up of the runoff in retention tanks and waste water treatment plants. Referring to pollution-transport processes the following sub-processes are taken into account: the atmospheric pollution and surface pollution dependent on the type of land use, and the matter transport in the sewer system. The sub-processes of matter accumulation and matter erosion on the land surface can be calculated by using mean values of pollution or, more detailed, by using special functions for processes of accumulation as well as erosion. In order to guarantee an easy application, the model's conception allows the use of input data and parameters of varying accuracy. Both, either measurements or statistical data can be used for the calculation dependent on the available data. The model is programmed in &amp;quot;C&amp;quot; and, therefore, usable on every established computer system. The model's validation succeeds for several sub-processes as well as sub catchments. Results of the model's application in the basin of the Havel river illustrate that the model calculates similar annual matter loads when compared to established other models. Furthermore, the results show the potential of the model to calculate the seasonal variation of matter loads and to calculate scenarios by using GIS based parameters. ArcEGMO-URBAN therefore is a capable tool for the identification of nutrient input from point sources on the scale of river catchments. / Diese Arbeit beschreibt die Konzeption und Realisierung des Modells ArcEGMO-URBAN sowie die Modellanwendung im Flussgebiet der Havel. ArcEGMO-URBAN wurde entwickelt um die punktuell in Gewässer eingetragenen Frachten von Gesamtstickstoff und Gesamtphosphor aus urbanen Räumen auf der Ebene von Flussgebieten zu bilanzieren. Die Nährstoffeinträge werden mit einer hohen räumlichen Auflösung und in ihrer innerjährlichen Dynamik berechnet, wobei der Einfluss des Niederschlagsgeschehens auf die Stoffeinträge besonders thematisiert wird. ArcEGMO-URBAN modelliert die Niederschlags-Abfluss- und die Schmutz-Transport-Prozesse in urbanen Räumen unter Berücksichtigung von naturräumlichen, technologischen und sozialen Parametern. Eingangsgrößen sind meteorologische und terrestrische Daten mit einer hohen zeitlichen und räumlichen Auflösung sowie statistische Angaben auf Gemeindeebene. Die digital vorliegenden Flächendaten werden vor der Modellierung mittels GIS-Funktionen ausgewertet und zu Flächen mit gleichen Eigenschaften zusammengefasst. Diesen Flächen werden technologische und soziale Parameter zugeordnet, welche aus den statistischen Angaben abgeleitet wurden. Durch die hohe inhaltliche und räumliche Auflösung der Eingangsdaten können relevante Prozesse teilflächendifferenziert beschrieben werden. Es können sowohl unterschiedliche Wasserver- und -entsorgungstechnologien und die durch sie induzierten Stoffströme als auch unterschiedliche Kanalisationsverfahren berücksichtigt werden. Bezogen auf den Niederschlags-Abfluss-Prozess werden die Abflussbildung und Abflusskonzentration auf befestigten Flächen, die Abflusstransformation und Überlagerung mit dem Trockenwetterabfluss im Kanalnetz und die Abflussaufteilung an Sonderbauwerken bzw. Kläranlagen berechnet. Für die Berücksichtigung der Stoff-Transport-Prozesse werden die durch die Atmosphäre und spezifische Nutzungen bedingten Stoffeinträge sowie der durch die Kanalisation bestimmte Stofftransport berechnet. Die auf der Oberfläche stattfindenden Teilprozesse von Stoffakkumulation und -abtrag können über mittlere Verschmutzungswerte oder detailliert über Akkumulations- und Abtragsfunktionen berechnet werden. Um ein weites Anwendungsspektrum zu gewährleisten, ist das Modell so konzipiert, dass eine Parametrisierung mit Eingangsdaten unterschiedlicher Qualität möglich ist. Abhängig von der verfügbaren Datenbasis werden entweder konkrete Messwerte oder statistische Größen verwendet. Das Programm ist in &amp;quot;C&amp;quot; programmiert und damit auf jeder Rechnerarchitektur lauffähig. Die Validierung des Modells gelingt für einzelne Teilprozesse aber auch für Teilgebiete gut. Die Ergebnisse im Flussgebiet der Havel belegen, dass das Modell ähnliche jährliche Nährstofffrachten wie bereits eingeführte Modelle berechnet. Darüber hinaus zeigen die Ergebnisse das Potenzial des Modells, die innerjährliche Dynamik punktueller Stoffeinträge abzubilden und durch die GIS-gestützte Parametrisierung aufwandsarm Szenarien zu berechnen. Damit ist ArcEGMO-URBAN ein geeignetes Modell zur Bestimmung von Nährstoffeinträgen aus punktuellen Quellen auf der Ebene von Flussgebieten.

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