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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.
131

[en] BIOGAS IN WASTEWATER TREATMENT PLANTS: THE MAIN LEGACIES OF THE BRAZIL-GERMANY TECHNICAL COOPERATION / [pt] BIOGÁS EM ESTAÇÕES DE TRATAMENTO DE ESGOTOS: OS PRINCIPAIS LEGADOS DA COOPERAÇÃO TÉCNICA BRASIL-ALEMANHA

HÉLINAH CARDOSO MOREIRA 26 December 2017 (has links)
[pt] Apesar dos avanços verificados nos últimos anos, o aproveitamento energético do biogás no Brasil ainda não é uma prática consolidada no tratamento de esgotos. Em estações de tratamento de esgotos (ETEs) com processos anaeróbios, o biogás se mostra como um produto estratégico econômico, social e ambientalmente, em muitos países do mundo, em especial na Alemanha. O projeto de cooperação técnica Brasil-Alemanha – PROBIOGÁS – foi o propulsor da discussão do biogás no saneamento no país. O presente trabalho retrata as principais ações e impactos do PROBIOGÁS no setor de tratamento de esgotos brasileiro e propõe uma continuidade às ações desenvolvidas por meio de instituições chave. Além disso, são levantados os desafios e perspectivas do biogás no setor, usando como base o histórico na Alemanha. No âmbito do PROBIOGÁS, os resultados foram bastante exitosos e consolidam as bases para o avanço do tema no Brasil. Como legados do projeto, desenvolveram-se diversas referências técnicas nacionais, promoveu-se a integração de diversos atores chave, fomentou-se a pesquisa aplicada e foram desenvolvidas capacidades de mil e oitocentas pessoas. Apesar disso, ainda se faz necessário que todo o conhecimento produzido seja replicado para as diversas realidades no país. Além disso, os principais desafios passam pela fragilidade da estratégia de gestão, pouca integração entre o desenvolvimento científico e sua aplicação, e necessidade de desenvolvimento de capacidades. Por fim, fica claro que, para o desenvolvimento de projetos de biogás de ETEs bem-sucedidos torna-se indispensável a incorporação do conceito de ETE Indústria. / [en] The current context of sewage treatment in Brazil is critical: only 40 percent of all generated wastewater is treated (ANA, 2015). Therefore, the expansion of the provision of sewage treatment services must take place within a scenario of investment difficulties, more stringent quality standards, higher energy and sludge operation costs and sewer rates that do not reflect real costs. Given that the provision of this service is not compromised and to move forward effectively on this issue, a change in management and paradigm breakdown must be done by establishing the concept of Industrial waste water treatment plant (WWTP). This concept envisions the WWTP as a closed loop, which receives an effluent for treatment and that through the efficiency of its processes delivers a treated effluent, seeking to optimize costs, recover and value the by-products and promote public health, based on a sustainable servicing of the institutional, social, environmental and economic dimensions. One of the potential by-products of sewage treatment is the biogas. This is because the UASB reactors for the treatment of domestic sewage is consolidated in the country (VAN HAANDEL et al., 2006; CHERNICHARO et al., 2015), considering the WWTP in operation, in different sizes and in the projects contemplated by the Growth Acceleration Program (PAC, in Portuguese). Chernicharo (2017) counted 908 anaerobic reactors that serve about 23 million inhabitants and routinely produce biogas. Considering the diagnosis of WWTPs carried out by the Agência Nacional de Águas - (2016), a Brazilian water agency, it shows that more than a third of the plants use anaerobic reactors. By transforming biogas from a by-product of the treatment process into a renewable energy source, WWTP also promotes a new level of service delivery, generating distributed energy that provides an improvement in the management of its energy and in the treatment processes. From the point of view of service provision, biogas plays a strategic role because it acts as a fuel to promote a sustainable service from a social, environmental and economic perspectives.
132

Contaminantes emergentes: ocorrência e distribuição espaço-temporal no rio do Monjolinho e avaliação da remoção pela estação de tratamento de esgotos de São Carlos / Emerging contaminants: occurrence and spatiotemporal distribution in the Monjolinho river and evaluation of removal rate by the sewage treatment plant of São Carlos city.

Campanha, Mariele Barboni 27 March 2015 (has links)
Made available in DSpace on 2016-06-02T20:35:03Z (GMT). No. of bitstreams: 1 6749.pdf: 21604971 bytes, checksum: ea6b5030f47becaef3fc6875b8d6bc0e (MD5) Previous issue date: 2015-03-27 / Universidade Federal de Minas Gerais / This work aimed to investigate the occurrence of 12 emerging contaminants (pharmaceuticals, hormones and triclosan) in samples of influents and effluents, as well the removal in the sewage treatment plant (STP) of São Carlos. It was also investigated the occurrence and spatiotemporal distribution of emerging contaminants in surface waters and sediments from the Monjolinho River, the receptor of effluents, and one of its tributaries, the Água Quente Stream (AQS), which receives the discharge of non treated sewage. Influent and effluent samples were collected weekly. Surface water and sediment samples were obtained every two and four months, respectively, in points since the source until the mouth of the Monjolinho River. The target compounds in dissolved fraction of aquous samples were extracted by solid phase extraction (SPE), while for sediments it was performed ultrassonic extrations with solvents followed by SPE. The analytical determinations were made by ultra high pressure liquid chromatography coupled to mass spectrometer equipped with triplequadrupole analyser (LC-MS/MS). The hormone 17-α-ethynilestradiol was not detected in any sample. However, all the pharmaceuticals evaluated and triclosan were detected in influent samples. The STP with upflow anaerobic sludge blancket (UASB) and air dissolved flotation in São Carlos presented low removal for carbamazepine, diclofenac, propranolol and ibuprofen. On the other hand, triclosan presented the highest removal (91.2%). In surface waters and sediments from Monjolinho river the concentration of contaminants presented an increasing trend since the source of the river to the downstream of the STP effluent discharge and after the confluence of the AQS (which flows into the river at the same place), where it was observed the highest concentrations in the Monjolinho River. The AQS, in its turn, presented higher concentrations of pharmaceuticals and triclosan than the Monjolinho River, due to the discharge of non treated sewage. Carbamazepine and diclofenac were persistent in both STP and aquatic body. The strong correlations between this compounds and electrical conductivity (considered a conservative parameter) sugests that CMZ and DCF can be tracers of both treated and non treated sewage release in the study area. Ee conclude that the main sources of phamaceuticals and triclosan to the Monjolinho River are the discharge of non treated sewage (from the AQS) and effluent from STP, since their removal is very low. Unlike the studies involving endocrine disruptors, the effects of other classes of emerging contaminants have been yet little explained in literature. Therefore, more surveys on the occurrence of these compounds combined with ecotoxicological studies must be conducted to make clear the magnitude of the impact that these substances can cause in the environment. Based on this information, adjustments in the effluent treatment may be investigated in the future, if there is interest in effectively removing this compounds in STP. / Neste trabalho foi investigada a ocorrência de 12 contaminantes emergentes (fármacos, hormônios e triclosan) em amostras de esgoto bruto e tratado, bem como foi avaliada a remoção dos mesmos pela estação de tratamento de esgoto (ETE) de São Carlos. Também investigou-se a ocorrência e distribuição espaço-temporal desses compostos em águas superficiais e sedimentos do rio do Monjolinho, o corpo aquático receptor, e em um de seus afluentes, o Córrego da Água Quente (CAQ), o qual recebe esgoto sanitário não tratado. Amostras de esgoto, águas e sedimentos foram coletadas semanalmente, bimestralmente e a cada quatro meses, respectivamente. No rio do Monjolinho, os pontos de amostragem abrangeram desde a nascente até a foz. Os compostos alvo na fração dissolvida das amostras aquosas foram extraídos por extração em fase sólida (SPE), enquanto que para sedimentos foi realizada extração ultrassônica com solventes, seguida de SPE. As determinações analíticas foram feitas por cromatografia de ultra eficiência acoplada à espectrometria de massas com analisador triplo quadrupolo (UPLC-MS/MS). O hormônio 17-α-etinilestradiol não foi detectado em nenhuma das matrizes avaliadas. Porém, todos os fármacos avaliados e triclosan foram detectados nas amostras de esgoto bruto. O tratamento de esgoto empregando reator anaeróbio de fluxo ascendente (UASB) seguido de flotação por ar dissolvido (FAD) na ETE de São Carlos apresentou baixa remoção para carbamazepina, diclofenaco, propranolol e ibuprofeno, enquanto o triclosan apresentou a maior remoção (91,2%). Nas águas superficiais e sedimentos do rio do Monjolinho as concentrações dos contaminantes foram crescentes desde a nascente até após a confluência do CAQ e o lançamento do efluente da ETE (os quais ocorrem no mesmo local), onde ocorreram as maiores concentrações encontradas no rio do Monjolinho. O CAQ apresentou concentrações mais elevadas de fármacos e triclosan do que o rio do Monjolinho, devido ao aporte de esgoto não tratado. Carbamazepina e diclofenaco foram persistentes tanto em amostras de esgoto quanto no corpo aquático. Fortes correlações entre ambos os compostos e condutividade elétrica (este considerado um parâmetro conservativo) sugerem que os dois fármacos são bons traçadores do aporte de esgoto sanitário tratado e/ou não tratado na área de estudo. Conclui-se que as principais fontes de fármacos e triclosan no rio do Monjolinho são o lançamento de esgoto não tratado (por meio do CAQ) e esgoto tratado, uma vez que a remoção dos mesmos na ETE, é bastante baixa. Ao contrário dos estudos envolvendo desreguladores endócrinos, os efeitos adversos de outras classes de contaminantes emergentes ainda têm sido pouco elucidados na literatura. Portanto, mais pesquisas sobre a ocorrência desses compostos aliados a análises ecotoxicológicas devem ser realizados para que se dimensione a magnitude do impacto que essas substâncias podem causar ao ambiente. Com base em tais informações, adequações no tratamento de esgoto podem ser investigadas, no futuro, caso haja interesse em remover efetivamente esses compostos na ETE.
133

Optimering av blåsmaskinstyrning på Bromma reningsverk / Optimization of blower control at Bromma wastewater treatment plant

Wikén, Moa January 2017 (has links)
The aeration step is the most energy consuming process in the wastewater treatment plant, i.e. making the energy usage in this step more efficient is of great concern both in Sweden and world wide. There are some examples of previous studies investigating ways to make the ae- ration control more efficient, though most of these have focused on for example ammonium feedback control rather than blower control which is the main focus of this study. Bromma wastewater treatment plant installed three new blowers in december 2016 functioning as suppliers of air to the aeration step in the bioreactor. Since there are still three old blowers operating at the WWTP, there is a need to control two different types of blowers efficiently. This is challenging since the two blower types have different capacities, efficiency and maxi- mum/minimum air flows and a control strategy that optimizes the operation of these two blower types combined needs to take this into account. Operational data for the blowers was used to generate a second grade polynome for each blower type which gives the efficiency as a function of produced air flow. These polynomes were further utilized to build a script in MATLAB that chooses the most efficient number of blowers operating and at what air flows for a certain total aeration need. The least square method was used to calibrate a model for calculating energy consumption for the simulated control strate- gy. Calculations for energy consumption from the current control strategy and another strategy proposed by the blower deliverer Sulzer were made in order to decide whether the optimized control strategy was an improvement or not. The simulation results and the calculations for energy consumption indicates that the current control strategy at Bromma WWTP is almost as effective as the optimized control strategy. Both strategies sets the new blowers at the first places in the queue. The optimized strategy appears to be more efficient for flows that requires both new and old blowers operating. From the calculations of energy consumption, it was shown that the control strategy from Sulzer de- mands an energy consumption on levels in between the one for the current control strategy and the optimized control strategy. / Luftningssteget är den mest energikrävande processen i ett avloppsreningsverk. Det finns därför incitament till att effektivisera energianvändningen då en minskad elförbrukning är positivt både ur ett ekonomiskt perspektiv och ur ett resursmässigt perspektiv. Energibesparingar från luftningssteget har undersökts tidigare genom att främst studera optimering av syreregleringen och luftregulatorn. Det här projektet syftar till att uppnå en minskad effektförbrukning på Bromma reningsverk genom att optimera blåsmaskinsregulatorn, ett mer outforskat forskningsfält.  På Bromma reningsverk installerades den 16 december 2016 tre nya blåsmaskiner som ska försörja luftningssteget i den biologiska reningen med luft. Det innebär att det finns två olika typer av blåsmaskiner som är i drift på Bromma: den gamla modellen (HST9000) och den nya modellen (HST40). Då dessa två olika typer av blåsmaskiner har olika kapacitet och verkningsgrad är det viktigt att blåsmaskinsregulatorn använder en styrstrategi som ställer dessa maskiner i kö på ett optimalt energieffektivt sätt. Det är även viktigt att i så stor utsträckning som möjligt låta maskinerna generera luftflöden nära sin högsta verkningsgrad.  Driftinformation för blåsmaskinerna användes för att med hjälp av beräkningar i MATLAB kunna välja ut det effektivaste antalet maskiner i drift, avgöra vilken typ av maskiner som ska användas samt vilket luftflöde respektive maskin ska generera vid ett specifikt luftflödesbehov. Målet var att hitta en optimal styrstrategi för Bromma reningsverk, samt att undersöka om det fanns möjligheter till energibesparingar jämfört med nuvarande implementerade styrstrategi. Effektförbrukningsberäkningar gjordes för både den simulerade optimerade styrstrategin och den nuvarande. Ytterligare en styrstrategi, föreslagen av blåsmaskinsleverantören Sulzer, undersöktes också ur ett energiförbrukningsperspektiv för jämförelse.  Resultatet av simuleringen och effektberäkningen indikerar att den nuvarande styrningen i princip är lika energieffektiv som den simulerade optimala styrningen. I båda fallen kopplas de nya maskinerna in i första hand. Dock visar resultatet på att den simulerade styrningen är effektivare vid flöden där det krävs att de gamla blåsmaskinerna sätts i drift. Sulzers föreslagna styrstrategi är mer energieffektiv än nuvarande styrning, men inte lika effektiv som den optimerade styrstrategin.
134

Bisfenol A ve vodním ekosystému / Bisphenol A in water ecosystem

Nohelová, Gabriela January 2014 (has links)
This diploma thesis deals with Bisphenol A, especially with its impact on the aquatic ecosystem. Information about its properties, production and current use are summarized here. Its harmful impact on the environment, especially on the aquatic ecosystem and the human body is characterized. Also the methods of its degradation within the aquatic environment have been described. A summary of the options of a determination of Bisphenol A in water samples is incorporated and the method of gas chromatography with mass spectrometry (GC/TOF MS) and comprehensive two-dimensional gas chromatography with mass spectrometry (GCxGC/TOF-MS) is compared in the experimental part. Analytical determination precedes the isolation of the analyte from the water samples by solid phase extraction (SPE) using SupelcleanTM ENVITM - 18 and derivatization using the silylation reagent, N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA). The result of this work is the analysis of a series of real samples from wastewater treatment plants Brno Modřice and Luhačovice by a two-dimensional gas chromatography with mass spectrometry (GCxGC/TOF-MS).
135

Metody rozpočtování inženýrských a vodohospodářských staveb / Methods of estimating costs for engineering and water management structures

Ovečková, Lenka January 2013 (has links)
Main intention of the thesis is to name and explain budgeting methods of building constructions with main focus on creating budget for water management and engineering structures. The practical part presents itemized budgets for a wastewater treatment plant and a bicycle trail. After that the price determined of the itemized budget is compared to the price determined by budget indicator.
136

Čistírny odpadních vod v horských oblastech / WWTP´s in mountains areas

Frank, Ivo January 2014 (has links)
Objectives of this master's thesis are to process review of technologies used to treat wastewater in alpine environment in Slovakia and in foreign countries. Thesis also includes mapping of situation of chosen alpine cottages in High Tatras. For cottages with unsuitable technology will be suggested more suitable solution.
137

Formy jištění obchodního rizika stavebního díla / Forms of Business Risk Protection of Construction Work

Štaffa, Jan January 2015 (has links)
This master’s thesis is focused on the business risk protection in construction projects. The first part is dedicated to an interpretation of theoretical knowledge which defines and describes the risk, acquaints readers with principles of the risk management and presents commonly used forms of the business risk protection in practice. The second part deals with a practical use of the protection tools and proposes their effective adjustment in the selected public works contracts.
138

Vliv specifické spotřeby flokulantu na odvodnitelnost čistírenského kalu / Dependence of Sludge Dewatering efficiency on amount of flocculant

Volejník, Tomáš January 2008 (has links)
The target of the first part of this diploma thesis is focused on the problems relating to the sludge production from the wastewater treatment plant and subsequent sludge treatment. Wastewater treatment plant and individual processes from the sludge management are described. The process of the sludge dewatering is described more extensively. Various methods of the dewatering and materials balance are described, too. The second part of this thesis is based on the experiment which took place on wastewater treatment plant Tetčice. The influence of the polymeric organic flocculant dosing on the sludge dewatering was monitored by this experiment. Dependence of the sludge dry matter and filtrate suspended solids content on the specific amount of flocculant was evaluated from experiment’s outputs. Using materials balance and outputs of the experiment, economical balance was made. It made possible to choose the most economic and technologically optimal way of the sludge dewatering on wastewater treatment plant Tetčice.
139

Studium průniku „musk“ sloučenin do abiotických a biotických složek vodních ekosystémů / Study of Transfer of Musk Compounds in Abiotic and Biotic Components of Aquatic Ecosystems

Zouhar, Libor January 2013 (has links)
This work was focused on the determination of musk compounds in various components of the environment. Synthetic musk compounds are organic substances commonly used as fragrant constituents of detergents, perfumes, cosmetics and other personal care products (PCPs). These compounds contaminate the aquatic environment through municipal wastewater from sewage treatment plants. The result is accumulation of these analytes in the environment and their occurrence in food chain. Synthetic fragrances are commonly detected also in human body; these substances generally belong among relatively new persistent organic pollutants (POPs) because of their persistence, bioaccumulation, and potential toxicity. The aim of this work was to optimize the methods for the determination of selected synthetic fragrances in wastewater (municipal, industrial) and in fish muscle. These analytes were determined in wastewater [the wastewater treatment plant (WWTP) Brno – Modřice, cosmetic manufacturing plant] and in fish Squalius cephalus that had been caught in the river Svratka. The selected analytes (14 substances) originate from the group of nitromusk, polycyclic musk and linear musk compounds. Solid phase microextraction (SPME) [for wastewater samples] and pressurized solvent extraction (PSE) [for fish samples] were used for isolation of analytes from real samples. The identification and quantification of analytes were carried out by high resolution gas chromatography coupled with mass spectrometry detection (GC-MS). The results show that galaxolide (g.L-1) and tonalide (tenths of g.L-1) were polycyclic musk compounds which were found at the highest concentration level in influent and also in effluent samples from the WWTP Brno – Modřice. The most extended nitromusk compound was musk ketone (hundredths of g.L-1). Linear musk compounds were detected in all influent samples (g.L-1). The overall removal efficiency of synthetic musk compounds from wastewater in the WWTP varies within the following ranges: nitromusk compounds 34.4 % – 85.4 %, polycyclic musk compounds 36.7 % – 53.3 % and linear musk compounds 90.5 % – 99.9 %. On the basis of the results it can be stated that wastewater (effluent from the WWTP) is the primary source of musk compounds, especially of the polycyclic ones in the environment. It has been also shown that ultrafiltration used in a cosmetic plant is a highly efficient technology for removing nitromusk and polycyclic musk compounds from industry wastewater. The results from evaluation of the fish contamination by musk compounds show that galaxolide was the substance which reached the highest concentration levels (tens of g.kg-1 l.w.). The results corroborate ubiquitous occurrence of musk compounds in the environment and reduction of using of nitromusk compounds due to their potential toxic properties. It has been shown that the insufficiency of the purifying procedures used in the WWTP Brno – Modřice has a significant influence on the concentration level of polycyclic musk compounds (tonalide, galaxolide) in fish caught from the river Svratka.
140

Monolitická nádrž ČOV / Cast-in-place tank of sewage plant

Kustyánová, Orsolya January 2016 (has links)
This thesis deals with the design and assessment of all supporting parts of a cast-in-place reinforced concrete tank of sewage plant in the village Vrbice. Tha main parts of the thesis are the technical report, static analysis, drawing documentations, construction process and visualisations. Calculation of internal forces was performed by the software Scia Engineer and verified by manual calculation. The drawing documentation constists of shape and reinforcement drawings of supporting parts.

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