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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.
71

Studie rekonstrukce úpravny vody / Reconstruction of Water Treatment Plant

Skříček, Jan January 2018 (has links)
The aim of the master thesis was to propose the reconstruction of the water treatment plant. I chose the water treatment plant in Čebín, which I have already describe with in the bachelor thesis. The water treatment plant has problems with increased iron, manganese and ammonium salts. In the first part I devoted myself to the current condition of the water treatment plant and the possibilities of removing the elements from the water. In the next chapter I compiled the equipment of the technological line. To remove iron and manganese, I suggested aeration using an injector, and for the removal of ammonium salts, potassium permanganate is used, which is used to regenerate the filters. A pair of pressure filters helps remove iron and manganese. In the last part of the thesis I described and evaluated the original condition of the water treatment plant. To evaluate the technical condition, I used the TEA Water web application.
72

Modelling control strategies for chemical phosphorus removal at Tivoli wastewater treatment plant

Rosendahl, Sara January 2021 (has links)
Wastewater compose an environmental risk as it contains high levels of nutrients, including phosphorus. Wastewater treatment plants (WWTPs) reduce phosphorus by using coagulants that precipitate soluble phosphate into metal phosphate, which is separated by settling. Coagulant flow is regulated by a control strategy, typically feedforward or feedback control. Feedforward is based on incoming wastewater disturbances whereas feedback control uses outgoing process values. Incoming phosphate is hard to measure and can be estimated using soft sensors. Modelling control strategies can help decide which strategy that is most suitable. Models describing phosphorus removal are Activated Sludge Model, ASM2d, and primary clarifier model. ASM2d models phosphorus precipitation and the primary clarifier model settling of particles. Tivoli WWTP faces challenges to reach effluent requirements of phosphorus. The wastewater flows through an equalisation tank, Regnbågen, before being pumped to Tivoli. Particulate matter settles in Regnbågen, which is removed by reducing the water level in Regnbågen. This rapidly increases incoming particulate load to Tivoli.Tivoli’s current control strategy is feedforward proportional to suspended solids. It is suspected, that this strategy overdose coagulant during the emptying of Regnbågen. The purpose of this thesis was to find the optimal control strategy for phosphorus precipitation at Tivoli WWTP, by using a model-based approach. Control strategies modelled are; feedforward, feedback and these two control strategies combined. Additional issues resolved are 1) calibration of a model that predicts the effect of chemical dosage on effluent phosphorus concentration from the primary clarifier, 2) calibrationof a soft sensor, 3) determination of which control strategy that is most suitable. ASM2d and a primary clarifier model were used to create a model describing chemical phosphorus removal. The calibration matches measured phosphate concentration, but underestimate peaks. The primary clarifier model was calibrated by minimising load differences for phosphate and total suspended solids, and was calibrated satisfyingly. A simplified soft sensor was constructed, described by a linear relationship between phosphate and pH. Three disturbances for feedforward control were analysed; measured phosphate, the soft sensors estimation of phosphate and Tivoli’s current controlstrategy. The optimal control strategy was found through a multi-criteria analysis. The optimal control strategy is the combined control strategy, when feedforward is proportional to incoming measured phosphate. The performance of all analysed feedforward disturbances were significantly improved when combined with feedback control. Furthermore, consequential errors are distinct when the soft sensor miss-predictincoming phosphate concentration. If the phosphate concentration cannot be correctly measured/estimated, feedback control alone has the best performance.
73

Využití separačních metod pro stanovení vybraných léčiv ve vodách / Application of separation methods for the determination of selected pharmaceuticals in waters

Burešová, Jitka January 2008 (has links)
Antibiotics are widely used pharmaceuticals in human and veterinary medicine. These compounds are biologically active. They decrease efficiency of biological processes in wastewater treatment plants. Antibiotics are not eliminated from sewage water completely and they are discharged as contaminants into the receiving waters. Several methods exist for the determination of antibiotics in sewage water. In the first place liquid chromatography, gas chromatography and capillary electrophoresis are used. The aim of this thesis was to developed a suitable izolation technique and an optimal analytical method for identification and determination of penicillins in wastewater. For determination was selected amoxicillin, ampicillin and benzylpenicillin (penicillin G). These are very often used penicillins. An optimized method was used for determination of these penicilins in real samples from a wastewater treatment plant situated in Veterinary and pharmaceutical university in Brno and from the large-scale wastewater treatment plant in Brno-Modřice. Real samples were concentrated using SPE (solid phase extraction). For penicillins determination were used high performance liquid chromatography with diode array detection (HPLC/DAD).
74

Vliv odtoku z čistíren odpadních vod na krasové toky / Effect of effluent from wastewater treatment plants on karst rivers

Schrimpelová, Kateřina January 2015 (has links)
Karst rivers are special type of rivers because of their hydrography conditions. They usually flow from non-karst area and as soon as they reach in to the karst area they disappear underground. There, they flow through cavities until they reach the surface again. The aim of this thesis is to assess the impact of water outflow from wastewater treatment plant on karst rivers. The study was done in the central area of CHKO Moravský kras where the impact of two WWTP on a cave system Rudické propadání – Býčí skála is evaluated. As a part of this study a half-year monitoring was carried out, which consisted of water sampling once every two weeks. In total, 13 water samples were taken from 8 sampling points. Also 4 additional one-time samples were taken from the cave system. Moreover, flow rate, temperature, conductivity, oxygen concentration and pH were measured at the sampling point. Afterwards, the content of undissolved solids, CODCr, BOD, N-NH4+, N-NO2-, N-NO3-, P-PO43- and total phosphorus were determined in the samples. The change of parameters in time and during the flow in the river was observed from the measured values. The balance of pollutants in particular parts of the river was calculated. The outflow values from waste water treatment plants were compared to the emission limits for surface waters and the parameters of rivers were compared to the environmental quality standards. According to the results, it can be observed that the water quality improves after passing through the cavities. It was proven that the outflows from the observed waste water treatment plants are negatively influencing the water streams. The most serious problem is the wash up of sludge from WWTP Rudice and its consequent sedimentation in the river and/or outflow to the Rudické propadání.
75

Návrh dezintegrační jednotky čistírenských kalů / Design of Sludge Disintegration Unit

Brtna, Filip January 2009 (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. In this thesis complete process of the wastewater treatment is described. Predominantingly is described the process in digestion tanks, therefore stabilization process, whereas the paper is focused on sludge pre-treatment (disintegration) of waste activated sludge before stabilization. The second part of this thesis is focused on the design of the disintegration unit for the wastewater treatment sludge in assist with experimental data. According to measured and fixed parameters the unfired pressure vessel has been designed. On the vessel has been further realized the strength calculation, the heat balance and the economic balance.
76

Návrh experimentální solární sušárny / Pilot Scale Solar Dryer Design

Plucar, Tomáš January 2011 (has links)
is Diploma’s thesis is addressing the issues of technical drying, principles and types of technical drying, solar drying possible usefulness of sewage sludge in the Czech Republic, its availability during the season, the legislation related to the processing of sewage sludge and design of pilot scale solar dryer.
77

Vliv obecní čistírny odpadních vod na jeskynní systém propadání Lopače / Effects of Municipal Wastewater Treatment Plant at Lopac Sinkhole Cave System

Ondruš, Martin January 2016 (has links)
The aim of this thesis is to assess the impact of water outflow from wastewater treatment plant on karst rivers. The study was done in the northern area of Moravský kras protected landscape, where the impact of WWTP Ostrov u Macochy on a cave system Lopačské propadání was studied. As a part of this study a half-year monitoring was carried out, which consisted of water sampling every two weeks. In total, 13 water samples were taken from 7 sampling points. Moreover, flow rate, temperature, conductivity, oxygen concentration and pH were measured at the sampling point. Afterwards, the content of undissolved solids, COD, BOD, N-NH4+, N-NO2-, N-NO3-, NKi and total phosphorus were determined in the samples. The change of parameters in time on the sampling points and further along the flow of the river was evaluated from the measured values. The outflow values from waste water treatment plants were compared with the emission limits for surface waters and the values of river water parameters were compared with the environmental quality standards. It wasn’t proven that the outflow from the observed waste water treatment plant is negatively influencing the water stream. The most serious problems are: -The WWTP was designed for treatment of sewage from Ostrov u Macochy, which involved separate sanitary and storm sewers. After finishing the WWTP, a uniform sewer was built. -High concentration of total phosphorus on the outflow from WWTP. -Poor quality of Lopač brook water already before the outflow vent from WWTP.
78

Optimalizace provozu stávající ČOV / Optimalization of WWTP operation

Ondráček, Martin January 2017 (has links)
The diploma thesis is focused on the optimalitzation of an operation on SWTP and improvement of figures of drainge from sewage water treatment plants. Possible options of the optimalization are also included. The second part of the thesis deals with the optimalization of operation of the concrete sewage water treatment plant using the WEST programme.
79

Srovnání účinnosti malých balených ČOV a kořenových ČOV / The comparison of two waste water treatment systems - constructed wetlands and mechanical.

Dudíková, Kristýna January 2010 (has links)
This thesis is focused to the comparison of two wastewater treatment systems - constructed wetlands and mechanical-biological wastewater treatment plant. The main goal of the theses is to compare two types of wastewater treatment systems and to evaluate hypothesis that constructed wetlands are cheaper and more efficient than mechanical-biological wastewater treatment plant. To be able to compare two various wastewater treatment systems 18 (9 constructed wetlands and 9 mechanical-biological plants, three size groups of both types of plants) wastewater treatment plant were chosen and compared. The treatment effectiveness, investment and operating costs, advantages and disadvantages of both the systems were compared. The information about all individual systems was obtained from the local municipalities, operators and partially from the Ministry of Environment of CR. Obtained data involved treatment technology, amount of annual treated water, building data and capital and operating costs. In some waste water treatment plant (WWTP) the water samples were taken and the analyses of chosen parameters (not measured in WWTP) were done. Once in 2010 year the samples of water, sediments and sludges were taken and the analyses of heavy metals was done. For assessment of operational problems in constructed...
80

OPTIMERING AV KVÄVEAVSKILJNINGEN PÅ AVLOPPSRENINGSVERKET I HALLSBERGS KOMMUN : EN TEKNISK-, EKONOMISK- OCH MILJÖMÄSSIG UTVÄRDERING

Grönlund, Lisa January 2011 (has links)
Avloppsreningsverket i Hallsberg kommun är beläget i direkt anslutning till Hallsberg, med Ralaån som recipient. Tekniken på reningsverket bygger på principerna för en klassisk aktivslamanläggning med mekanisk rening, kemisk rening, biologisk rening och en slambehandling där rötning av primär- och sekundärslam används för utvinning av biogas. Hallsberg ARV har under en längre tid haft problem med kvävereningen. Under senaste åren har man överskridit riktvärdet för kväveutsläpp vid ett flertal tillfällen och under 2009 överskreds även gränsvärdet. Riktvärdet för Hallsberg ARV är i dagsläget satt till 10mg NH4-N/l som medelvärde per månad, gränsvärdet är satt till 10 mg NH4-N/l som medelvärde per kalenderår. Då Hallsberg ARV inte drivs vid full kapacitet antas en minskning av kväveutsläppen vara möjlig att genomföra genom trimning av befintligutrustning och processer på verket. Detta antagande låg till grund för det här examensarbetet som syftar till att optimera kvävereningen på Hallsberg ARV. I optimeringen ingick en teknisk, ekonomisk och miljömässig utvärdering av olika alternativa lösningarna för att förbättra funktionen hos anläggningen. Extra hänsyn togs till energi- och kemikalieåtgång i syfte att få en så effektiv drift av verket som möjligt. Arbetet genomfördes genom en initial litteraturstudie på området, vartefter en provtagningsserie om fyra veckor realiserades på verket. Data som ligger till grund för slutsatserna i projektet har också inhämtats från onlinemätare på verket samt från äldre externt analyserade prover. Efter analys av insamlad data antas orsakerna till Hallsberg ARV:s höga utsläpp av kväve bero på en kombination av flera faktorer: -Vid vår och höst kan brunnsslamintaget vara så stort att bräddning sker ut till verket. Detta leder till att kvävebelastningen höjs så kraftigt att nitrifierarna inte hinner acklimatisera sig och får förhöjda kväveutsläpp till följd. -Mycket kväve följer med slammet från simultanfällningen till rötningen. Detta kan påverka halten kväve i rejektet från rötkamrarna som i sin tur kan leda till störningar i kvävereningen. -Centrifugens rejekt innehåller mycket kväve och körs idag endast under ett par dagar i veckan vilket leder till stora variationer i inkommande kvävehalt. -En hög förfällning av fosfor och organiskt material har bidragit till en låg halt av organiskt material i denitrifikationen. Sammantaget föreslås att vidare studier bör genomföras av ovan nämnda områden för att driften på Hallsberg ARV ska kunna drivas med så låga miljömässiga och ekonomiska kostnader som möjligt. / The waste water treatment plant in Hallsberg municipal is situated adjacent to Hallsberg, with Ralaån as a recipient. The technique at the waste water treatment plant is based on the principles for a classical activated sludge treatment plant and includes mechanical treatment, chemical treatment, biological treatment, and a sludge treatment where the digestion of primary and secondary sludge is used for extraction of biogas. Hallsberg waste water treatment plant has during some time had problems with the nitrogen removal with high nitrogen emissions as a consequence. The target value has been exceeded a couple of times during the last years and in 2009 the limit value was exceeded as well. The target value for Hallsberg waste water treatment plant is 10 mgNH4-N/l as an average value per month, the limit value is set to 10 mg NH4-N/l, as an average value per year. Since the waste water treatment plant in Hallsberg not is operating at full capacity, a lowering of the nitrogen emissions is assumed to be possible though a trimming of the existing equipment and of the processes on the site. This assumption formed the basis for this thesis, designed to optimize the nitrogen removal at the waste water treatment plant in Hallsberg. A technical, economical and environmental evaluation was included in the optimization to improve the function of the plant. Extra evaluations were made in the energy- and chemical consumption in order to streamline the operations at the plant as much as possible. The project was carried out through an initial literature-investigation followed by a four week period of sampling and analyzing at the site. The data that form the conclusion in this project has also been collected through online measurements at the plant as well as through analyses of older samples. After analyzing the collected data, the reasons for the high emissions of nitrogen is thought to be due to a combination of reasons: -During the spring and the autumn the external intake of well sludge can lead to a direct release of sludge in to the plant. The change of nitrogen content will not give enough time for the nitrifying bacteria to acclimatize, with elevated emissions of nitrogen as a consequence. -The usage of simultaneous precipitation could lead to an irregular concentration of nitrogen released to the treatment plant from the digesters. This in turn could contribute to higher nitrogen emissions. -The irregularities of the usage of the centrifuge contribute to nitrogen irregularities and contribute to the difficulties of acclimatization of the nitrifying bacteria. -A high pre-precipitation of phosphorus and organic matter has contributed to a level of organic material in the denitrifikation below what is recommended. To sum up, further investigations are suggested in the above mentioned areas to make the operations at the plant carried trough at the lowest possible environmental and economically cost.

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