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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

Odstraňování mikroplastů z vody / Removal of microplastics from water

Skalníková, Andrea January 2021 (has links)
The aim of this diploma thesis is to investigate the removability of microplastsic particles with different shapes (fragments, sphers, fibers) by standard water treatment process, such as coagulation, filtration and sedimentation. For the experimental purpose in this study, polyvinyl chloride with a size ≤ 50 μm and a density of 1.38 g/cm3 , was used as a representative of microplastics. The coagulation has been provided by ferric sulphate in pH range 5, 6, 7 and 8 and at a diferent dose of coagulant 20, 40, and 60 mg/l. The study results has shown, that the coagulation efficiency of polyvinyl chloride particles were affected by pH. The optimal value of pH has been 7 at the coagulant dose of 20, 40 and 60 mg/l. The presence of polyvinyl chloride shown a positive effect on coagulation. It has been reflected in a reduction of the residuals of iron concentration after coagulation, at pH 5-7. Solution with polyvinyl chloride contained 1,2 mg/l dissolved organic carbon. After fitlration the concentration decreased up to 70 % at pH 7 at dose of coagulant 40 and 60 mg/l. Experiments have shown that polyvinyl chloride particles are capable of faster sedimentation after coagulation. The flocs formed during coagulation interacted effectively with the polyvinyl chloride particles and facilitate their removal...
72

Vliv čistírny odpadních vod v obci Luka nad Jihlavou na kvalitu řeky Jihlavy

Hanáček, David January 2019 (has links)
Diploma thesis is focused on the assessment of the impact of sewage treatment plant in the village of Luka nad Jihlavou on the quality of the river Jihlava. Assessment of the influence of the WWTP is based on field monitoring, with sampling of water for subsequent laboratory analysis. The literary research deals with the purification and treatment plants, water legislation, types of water, pollution of surface water, death of fish on accidental water pollution and evaluation of water quality according to ČSN 75 7221 and government Regulation no. 401/2015 Sb. In the literary overview is also given the description of the indicators field monitoring and laboratory determinations. The methodological section describes the principles of individual determination of the field survey and analyses of water samples in the laboratory and characteristics of the sampling sites. Results and discussion chapter based on the graphically processed results to assess the impact of WWTP on water quality in the river Jihlava. From the obtained data it follows, that, despite some exceedances of the limit the boundaries of reading to CSN 75 7221 and government Regulation no. 401/20015, does not significantly affect water quality in the receiving water and not accidental mortalities of the fish community.
73

Problematika kvality pitné vody v nemocnici Prachatice / The quality of drinking water in the Hospital Prachatice.

ROSOVÁ, Monika January 2017 (has links)
This diploma thesis deals with the drinking water quality in the Prachatice Hospital. In every healthcare facility, it is essential to maintain and monitor the quality of drinking water. The diploma thesis has the following objectives: Evaluation of the quality and quantity of drinking water and hot water at the Prachatice Hospital in certain time periods, comparison between another hospital in the South Bohemian region with the occurrence of Legionell in the given period, the possibility of solving crisis situations in accidents in the healthcare facility and possibilities of rainwater use in the Prachatice Hospital. The thesis is divided into theoretical and practical parts. The theoretical part of the thesis describes basic concepts related to the quality of drinking water, indicators of drinking water and a section is devoted to a water accident in the Prachatice Hospital in the autumn of 2015. The practical part was processed by the method of secondary analysis of data. The necessary data for the analysis was obtained directly at the Prachatice Hospital and at the Regional Hygiene Office in České Budějovice. For the analysis, data from January 2011 to January 2017 was used and processed in Microsoft Excel into tables and charts. The results show the overall drinking water supply situation in the Prachatice Hospital. The work could draw attention to the problems and issues associated with emergency situations, for example. Hospital management and professionals in drinking water technology department can get a comprehensive overview of the hospital's drinking water supply from its own well, public well and the public water supply.
74

Vyhodnocení minimálních nočních průtoků ve vodovodní síti / Assessment of minimal night-flows in the water supply network

Nováková, Jana January 2018 (has links)
This diploma thesis is focused on assessement of the minimum night flow in the water supply system. The first part of the work is focused on the research of foreign and Czech literature in the area of evaluation of water losses in water systems, evaluation and measurement of minimum night flow and comparison of values of individual indicators in the Czech Republic. In the practical part of the thesis, the minimum night flow is estimated and the water losses indicators are determined for selected DMA of Vsetin´s watter supply system, which is operated by VaK Vsetin, a.s.
75

Analýza spotřeby vody ve vodovodní síti Valašského Meziříčí / Assessment of drinking water consumption in the water supply network of the Valašské Meziříčí

Fučík, David January 2019 (has links)
This diploma thesis deals with the analysis of the time series of drains from the water reservoir and evaluation of the minimum night flow in the water supply network of the town of Valašské Meziříčí. In the theoretical part of this thesis were elaborated research of Czech and foreign literature focusing on drinking water consumption analysis, measurement and evaluation of minimum night flow and methods of determination of water losses in distribution systems. The practical part includes analysis of water outflows from reservoirs, evaluation of minimum night flow and determination of basic water loss indicators for selected district metered areas of the network. The above-mentioned water supply network is operated by the Vak Vsetín, a.s.
76

Studie úpravny vody z povrchového zdroje / Study of water treatment plant from surface source

Inwald, Petr January 2021 (has links)
The first part of the thesis deals with water sources and methods of drinkable water treatment. This section describes the technologies used for two-stage water treatment from a surface source. The second part deals with study of the new drinking water treatment plant from a surface source for Adamov town. The work documents the current state of the existing water treatment plant and describes used technology with a design flow Q = 30 l s-1. In the next part of thesis is design of two variations of new technological line with a design flow Q = 10 l s-1. The first variation is one-stage water treatment with pressure filters as the main separation stage. Two-stage water treatment is designed for the second variation, in which the first stage of separation are clarifiers and the second stage are pressure filters. Thesis includes drawing documentation of designed pressure filters and clarifiers, technological and height scheme of both variations.
77

Struktura, dynamika a reaktivita hydratovaného elektronu / Structure, dynamics and reactivity of the hydrated electron

Uhlig, Frank January 2014 (has links)
Structure, dynamics and reactivity of the hydrated electron Frank Uhlig In this work, one of the products of ionization of water, namely the hydrated electron, has been investigated. The hydrated electron is a key-intermediate in aqueous radiation chemistry. Although known to exist for over 50 years, its structure remained elusive and under discussion up to the present day. We show in this work, that we can obtain a faithful picture of the hydrated electron, its equilibrium structure, dynamics after attachment to water, and its reactivity, using ab initio methods. To this end, small cluster models and extended bulk and slab geometries of water including an excess electron have been investigated.
78

Hodnocení kvality vody v úpravně pitné vody Mokošín / Evaluation of water quality in water treatment plant Mokošín

Vosáhlo, Jan January 2012 (has links)
The theme of this thesis is " Evaluation of water quality in water treatment plant Mokošín". The source of water supply are 4 artesian wells. The paper first describes the supply area and water treatment plant with individua water treatment technologies. In the practical section there is the specification of contaminating elements required to be separated at the water treatment plant. Since it is an underground source of water, there is an increased amount of iron and manganese. Increased attention is given to arsenic, which occurs in two water sources in recent years. There are also offered the possibilities of removing arsenic at water treatment plant and two filter materials tested in the laboratory. Monitoring of water quality takes place always in resources and after treatment in the time period of five years, the arsenic values are reported for ten years.
79

Hodnocení kvality vody a sedimentů v povodí Kunratického potoka / Evaluation of the quality of water and sediments in the basin Kunratice stream

Uhrová, Adéla January 2014 (has links)
This thesis deals with the monitoring of water quality and aquatic sediments analysis in the basin of Kunratický brook. Water samples were collected at six locations during once year. The results of analysis were evaluated according to CSN 75 7221 Water quality - Classification of surface water quality and Regulation 229/2007. According to CSN 75 7221 Kunratický brook is classified as very strong polluted water. Biological consumption of oxygen, ammoniated and nitrate nitrogen meet not the conditions of environmental quality according to Regulation 229/2007. Sediment samples were collected once for whole period at 4 locations. In sediment was determine the content of metals. The results of analysis were evaluated according to Regulation 257/2009. The results were compared with limits of US EPA, specifically PEC and TEC. Sediments of pond Šeberák are full obliged. Zinc, lead and cooper are in excess of sediments of Kunratický brook. Key words: water quality, sediments quality, basin
80

Chemismus vody a sedimentů fluviálních jezer Labe / Water and sediment chemistry of fluvial lakes of the Elbe River

Chalupová, Dagmar January 2011 (has links)
The presented paper aims at the problems of fluvial lakes in middle course of the Elbe River which has been influenced by the human activity since the Middle Ages. The oxbow lakes which are extremely precious ecosystems contributing to the stability of the river ecosystem show not only the changes of the course of the Elbe River. With regard to sedimenting a great amount of pollutants, these lakes also tell about the industrial pollution to which the river was exposed mainly in the second half of the 20th century due to insufficient precautions on industrial sources causing contamination. 5 cut lakes between Hradec Králové and Mělník have been studied within this research. These lakes differ in the intensity of communication with the river, in the distance from significant sources of industrial pollution and in the use of nearby land. The research included morphometric and bathymetric measures, observation of hydrological regime, seasonal measures in the water column and regular analysis of surface water samples. Profiles of sediments in the length that the used technology allowed were sampled, so that older anthropogenic load could be found out. The amount of organic carbon and concentration of selected metal and arsenic (Ag, Cd, Cr, Cu, Fe, Hg, Mn, Pb and Zn) were stated apart from grain size...

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