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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

Vliv tlakových poměrů ve vodovodní síti na spotřebu vody / Impact of pressure condition on water consuption in water distribution network

Straňák, Petr January 2019 (has links)
The diploma thesis deals with effect of pressure conditions in the water supply network on consumption of drinking water. The introductory part describes how pressures affect water consumption and six studies from different countries carried out on real network are presented. Further, the work is devoted to other factors influencing water consumption and distribution of domestic water consumption. The practical part deals with the laboratory measurement of the influence of pressure change on tested discharge fittings for flowing and dripping water. The results are also expressed in annual costs and a method is presented how the effect of pressure change can be quantified if we know the average daily consumption and its distribution.
282

Studie sanace vybrané části stokové sítě / Study of rehabilitation of the selected part of the sewer network

Novák, Tomáš January 2019 (has links)
The aim of this diploma thesis is a rehabilitation study of the sewer network on Vídeňská street in the city of Brno. The first part of the thesis includes an accompanying review including basic data about the sewage gutter, including the characteristics of the affected area with a detailed description of the geological and hydrogeological rates. This is followed by a technical review, which consists of hydrotechnical calculations and overal summary of the construction-technical condition. The subject of the following part is a proposal and description of several varying solutions for the rehabilitation, including, particularly, trenchless technologies. Further on, all of the proposed variants are evaluated based on technical, economical and environmental impact. Finally, all the observations are summarized and a final recommendation for the way of solving the rehabilitation is carried out.
283

Studie variant odkanalizování obce Kamenný Malíkov / The study alternatives village sewer system Kamenný Malíkov

Rőssová, Markéta January 2019 (has links)
The diploma thesis is focused on the possibilities of drainage of waste water and its subsequent liquidation in the village of Kamenný Malíkov. The aim of this diploma thesis is the elaboration of variant solutions for drainage of Kamenný Malíkov. Furthermore, the proposal for wastewater treatment, the economic comparison of variants and the recommendation of the unsuitable variant. The diploma thesis deals with the proposal of predominantly gravitational way of drainage of waste water in combination with the pressure, due to incline terrain in the village. Each eventuality has wastewater treatment method designed.
284

Posouzení účinnosti pokročilých oxidačních procesů prostřednictvím testů ekotoxicity / Assessment of the effectiveness of advanced oxidation processes via ecotoxicity tests

Procházková, Petra January 2019 (has links)
Recently, an increasing problem in wastewater treatment is the insufficient removal of organic pollutants. These substances can be toxic to the environment already in a small amount, either acutely or chronically. The goal is therefore to develop of technologies that ensure their effective removal. One possibility is to use advanced oxidation processes. Advanced oxidation processes work on the principle of non-selective oxidation mediated by OH radicals. Several methods such as O3/H2O2 (Peroxone), UV/H2O2 or Fenton´s reaction can be used to generate them. The aim of this thesis was to evaluate the effectiveness of the used advanced oxidation processes in wastewater treatment via ekotoxicity tests. Wastewater samples treated with advanced oxidation processes on the pilot unit showed low values of acute toxicity for selected test organisms (D. magna, T. platyurus, S. alba, L. minor). For the sample of waste water that was treated with the UV/H2O2 on AOP laboratory unit, there was an increase in acute toxicity on the testing organism D. magna and L. minor. The similar effect was observer in the tests with the D. magna with the model samples treated with the same method, while the tests on the L. minor showed a reduction in toxicity.
285

Agregační reakce chitosanu využitelné při úpravě pitné vody. / Aggregation reactions of chitosan in drinking water treatment

Leskovjanová, Jana January 2008 (has links)
The diploma thesis deals with treatment of surface waters containing humic substances. The most often used method of surface water treatment is coagulation with subsequent separation of aggregates. In this study, only perikinetic coagulation phase was studied. It is the phase when aggregates are formed by the Brownian motion only, i.e. without mixing. Separation of the formed aggregates was made by centrifugation. Coagulation tests were made under the laboratory conditions with model humic water. Humic substances were added from a concentrate, which was taken from a natural peatbog. The influence of temperature on the coagulation process was studied, ranging from 5 to 22 °C. Chitosan (natural biopolymer) was used as coagulant. In present, it is not used in Czech water treatment practice yet. No effect of temperature was observed when chitosan was used as coagulant. Influence of temperature was also studied with the use of aluminium and ferrous sulphates, which are used in common praxis as coagulation reagents. Influence of the temperature was observed and is in agreement with previously reported data of pilot-plant experiments by other researchers. Spectroscopic methods were used to evaluate the coagulation efficiency and determine residual concentration of aluminium and ferrous coagulant. Chemical oxygen demand (COD) was determined for optimal doses. At first, coagulation tests were made under the laboratory temperature. This tests determined optimal aggregation time and optimal coagulant dose under low temperature. Afterwards, all coagulants used were compared at given temperatures.
286

Studium adsorpce přirozených organických látek na aktivním uhlí při úpravě pitné vody / Adsorption of natural organic matter (NOM) on granular activated carbon in the treatment of drinking water

Le Duc, Duy January 2008 (has links)
In the first part of this thesis the methodic of lab trial was studied, which will be useful for studying adsorption of natural organic matter by activated carbon. As an optimal method of testing adsorption characters jar testing was chosen. Again as an indicator of organic contamination, it was decided to use permanganate chemical oxygen demand (in Czech CHSKMn) will be used. In the second part of this thesis the adsorption characters of eight types of granular activated carbon were studied. Those granular activated carbon came from two world produces, from company NORIT five type of granular activated carbon were tested: NORIT GAC 1020, NORIT PK 1-3, NORIT GAC 1240, NORIT ROW 0.8 SUPRA a TOD NORIT ROX 0.8 and from company Chemviron Carbon three types of granular activated carbon were tested: F100 FE11120A, F400 FE11210A a TL830 FE2028B. Batch kinetic tests of natural organic matter adsorption were conducted with all types of granular activated carbon at first. For description of sorption not only the batch kinetic tests and duration needed for setting equilibrium were observed, but also the process decreasing of concentration of natural organic matters to the value of equilibrium concentration known as adsorption equilibrium was followed.
287

Retence vody v huminových kyselinách / Water retention capacity of humic substances

Cihlář, Zdeněk January 2009 (has links)
Humic acids were extracted from South Moravian lignit. That humic sample was oxidized by either H2O2 or HNO3. In next step, oxidized humic acids were polymerized by formaldehyde in order to obtain cross-linked structures with improved water retention capacity. Affinity to water and water retention capacity of obtained products were studied by thermal analysis (DSC – differential scanning calorimetry and TGA – thermogravimetric analysis). In order to study above-mentioned parameters two different methods were used. First approach represented sorption of water to humic acids from three controlled humidities, for description of those processes TGA measurement was used. Second study was based on the DSC monitoring of water excess sorption. Results obtained from TGA measurements showed an increasing sorption ability with increasing relative humidity of the environment. DSC measurerents in hermetically sealed containers resulted in an increasing content of water bound by humic acids structures. All the modified samples of humic acids (oxidized as well as oxidized and modified by formaldehyde) gave higher retention capacity in comparion with the parental humic sample.
288

Optimalizace provozních parametrů na úpravně vody Bzenec-Přívoz / Optimization of operating parameters in drinking water treatment plant in Bzenec-Přívoz

Sukopová, Martina January 2010 (has links)
Water treatment plant Bzenec Přívoz represents important supply of potable water for Hodonín district. After a longtime operation it was in 2008-2010 reconstructed in order to make water treatment technology more effective. The basic step was dividing technology into one stage and two stage water treatment for particular spring areas of ground water. The character of raw water requires effective removal of iron and manganese, therefore intensification and optimization of operating parameters were the purposes of the project. Installation of new aerators and hyperboloid stirrers in flocculation tank required an operating tests for proving of high technological efficiency while the operating costs were decreased. The water treatment process was completly automatized, which made the operation easy and minimized human element impact. Results of the reconstruction are more effective water treatment and a distinct decrease of operating costs.
289

Monitoring obsahu fosforu a dusíku v odpadních vodách / Monitoring of the contents of phosphorus and nitrogen in wastewater

Herka, Milan January 2014 (has links)
This master´s thesis is focused on the occurrence of phosphorus and nitrogen in effluents and methods of their determination. In the theoretical part of the thesis describes methods for the determination of nitrogen and phosphorus in waste waters, their selection and optimization methods including mobile analytics. Experimental section is devoted to the abstraction of wastewater from selected wastewater treatment plants and their analysis methods including mobile analytics and comparing them with the presentation of their results. The conclusion is drawn evaluate the content of nitrogen and phosphorus in wastewater influent and effluent from wastewater treatment plants and compared the variation of these values during the one-month study and compared with published data.
290

Posouzení účinnosti čištění odpadních vod pomocí testů ekotoxicity / Assessment of the efficiency of wastewater treatment plant using ecotoxicity tests

Urminská, Barbora January 2015 (has links)
The possibilities of environmental pollution control are increasing and more advanced wastewater treatment methods are being emphasized, as well as more specific control of contaminants presence in treated waters. That is why it becomes relevant to perform not only chemical analysis but also ecotoxicological bioassays as the means of evaluation of biological effects caused by wastewater discharges to ecosystems. No wastewater treatment plant is able to treat the water perfectly – it can only decrease the pollution level to an acceptable value. Therefore it is important to find out if the treatment process is sufficient to provide a satisfactory decrease of ecotoxicity and also what effects to the organisms in recipient will be caused by wastewater discharges. The thesis is focused on the evaluation of wastewater ecotoxicity. In the experimental part of the thesis, wastewater samples were collected at four wastewater treatment plants in the Czech Republic. At one of them also the sludge samples were taken. The aim was to evaluate the efficiency of wastewater treatment by selected ecotoxicological bioassays. The results have shown that the efficiency of wastewater treatment plants with secondary treatment is sufficient to reduce acute toxic effects to the minimum. Average toxicity removal was over 80 % at three of four evaluated wastewater treatment plants. At the fourth WWTP it was 41 %, however, at this WWTP high efficiency of treatment is not necessary.

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