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Advanced removal methods of matter difficult to coagulate during drinking water treatment
Sichrová, Kateřina
Nowadays, drinking water treatment (DWT) is becoming more and more challenging due to the increasing anthropogenic pollution as well as due to the impacts of climate change. Water sources commonly comprise a cocktail of undesirable substances, the removal of which by the conventional DWT process based on coagulation/flocculation is often insufficient. This dissertation deals with advanced removal methods, particularly adsorption, usable for difficult to coagulate substances during DWT. Particular emphasis is placed on removing manganese, algal organic matter (AOM), and per- and polyfluorinated alkyl substances (PFAS). Additionally, in the case of emerging anthropogenic pollutants, attention was also paid to their occurrence and interactions in water. As part of the research, a new TiO2-based adsorbent was synthesized for Mn2+ removal. Since the prepared adsorbent showed high Mn2+ removal efficiency in a much wider range of pH values compared to the conventional demanganization method, which requires very high pH values, it could serve as a suitable alternative demanganization method. Regarding the removal of AOM, the influence of solution properties on its adsorption onto different types of granular activated carbon (GAC) was thoroughly investigated. It was found that the efficiency of AOM...
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Advanced removal methods of matter difficult to coagulate during drinking water treatment
Fialová, Kateřina ; Pivokonský, Martin (advisor) ; Mašín, Pavel (referee) ; Brányik, Tomáš (referee)
Nowadays, drinking water treatment (DWT) is becoming more and more challenging due to the increasing anthropogenic pollution as well as due to the impacts of climate change. Water sources commonly comprise a cocktail of undesirable substances, the removal of which by the conventional DWT process based on coagulation/flocculation is often insufficient. This dissertation deals with advanced removal methods, particularly adsorption, usable for difficult to coagulate substances during DWT. Particular emphasis is placed on removing manganese, algal organic matter (AOM), and per- and polyfluorinated alkyl substances (PFAS). Additionally, in the case of emerging anthropogenic pollutants, attention was also paid to their occurrence and interactions in water. As part of the research, a new TiO2-based adsorbent was synthesized for Mn2+ removal. Since the prepared adsorbent showed high Mn2+ removal efficiency in a much wider range of pH values compared to the conventional demanganization method, which requires very high pH values, it could serve as a suitable alternative demanganization method. Regarding the removal of AOM, the influence of solution properties on its adsorption onto different types of granular activated carbon (GAC) was thoroughly investigated. It was found that the efficiency of AOM...
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Occurrence and removal of polluting organic substances during drinking water treatment
Prokopová, Michaela ; Pivokonský, Martin (advisor) ; Brányiková, Irena (referee) ; Kříženecká, Sylvie (referee)
Water sources pollution by natural organic substances and anthropogenic micropollutants is a global problem with a significant impact on water treatability and drinking water quality. One of the current topics is the proliferation of algal and cyanobacterial cells and the associated release of algal organic matter (AOM). The presence of AOM in drinking water sources can deteriorate the water's taste and odour or serve as precursors of disinfection by-products., especially in the case of a high proportion of the non-proteinaceous AOM, which is difficult to remove by conventional coagulation/flocculation. A part of this thesis is devoted to the composition and characterization of AOM, its chemical coagulation and electrocoagulation, and the assessment of the ozonation of the non-proteinaceous AOM during drinking water treatment. The second part of this thesis deals with the occurrence, characterization and removal of persistent anthropogenic substances, namely microplastics (MPs) and per- and polyfluoroalkyl substances (PFAS), during the drinking water treatment. Based on the results of ozonation of the non-proteinaceous AOM fraction (NP), it was found that ozonation caused a change in the surface charge, molecular weight or partial mineralization of NP, depending on ozonation conditions (O3 dose, pH...
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Ověření účinnosti filtrace přes granulové uhlí při odstraňování mikropolutantů na vybraných úpravnách pitné vody
MARTANOVÁ, Andrea
My bachelor thesis is called Verification of filtration efficiency through granular carbon in removal of micropollutants in selected drinking water treatment plants. The aim of this work was to determine the efficiency of granular activated carbon (GAC) filters in connection with other technological processes (especially with ozonisation). Passive samplers (POCISs) were installed at the drinking water treatment plants in Pilsen and in Plav during spring and autumn 2019. Moreover, grab water samples were taken in the first and last day of POCIS deployment. Concentrations of selected pesticides and pharmaceuticals were determined by a liquid chromatography with a tandem mass spectrometry in a laboratory LECHB Vodňany. In particular, the results of the analysis showed the occurrence of telmisartan and metabolites of metazachlor (metazachlor ESA and metazachlor OA) and metolachlor (metolachlor ESA) in raw water. Telmisartan was reduced in final water unlike metazachlor ESA, which seemed to be problematic in final water in the spring campaign at drinking water treatment plant in Pilsen. The results also confirmed the occurrence of atrazine and its metabolites in raw water. Furthermore, elevated concentrations of some compounds were found before the GAC filters than in the inlet to the drinking water treatment plants. The concentrations of these compounds were lower in the outlet than before GAU filters. The removal efficiency was calculated not only for all compounds together but also for each compound individually. Evaluation showed higher total removal efficiency at drinking water treatment plant in Pilsen, where the removal efficiency was 99 % in the autumn campaign, while in the spring campaign removal efficiency was only 61 %. The reason for this difference could be deactivated ozonisation during the spring campaign. This result demonstrates possibility of high removal efficiency of micropollutants for ozonisation followed by GAC filtration. Removal efficiency for drinking water treatment plant Plav was set as 46 % in the spring campaign and 67 % in the autumn campaign. The reason for these low removal efficiencies may be missing of ozonisation in treatment technology at this drinking water treatment plant.
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Coagulation of organic matter produced by phytoplankton
Načeradská, Jana ; Pivokonský, Martin (advisor) ; Benešová, Libuše (referee) ; Janda, Václav (referee)
This dissertation thesis focuses on the removability of algal organic matter (AOM) by coagulation during water treatment and also on the influence of AOM on the coagulation of other substances present in source water. Special emphasis is put on the description of coagulation mechanisms. The effectiveness of AOM removal by coagulation was investigated by coagulation tests performed with optimized doses of coagulants (aluminium or ferric sulphate) under different pH values. Peptides and proteins contained in cellular organic matter of cyanobacterium Microcystis aeruginosa were used in the experiments since they have been previously reported to disturb the coagulation process. Moreover, peptides and proteins underwent coagulation experiments together with kaolin particles, representing clay particles in turbid waters, in both the presence and absence of coagulants to investigate the effect of AOM on the coagulation of turbid waters. To enable the description of coagulation mechanisms, AOM were characterised in terms of charge, functional groups, molecular weight and ability to form dissolved complexes with coagulant metals. The experimental results demonstrated that the removability of peptides and proteins is greatly dependent on pH value and on the properties of the involved particles or molecules....
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Per- and polyfluoroalkyl substances in drinking water
Skalický, Daniel ; Načeradská, Jana (advisor) ; Semerád, Jaroslav (referee)
Per- and polyfluoroalkyl substances are synthetic organic compounds which, due to their physicochemical properties, have a high application in many consumer products such as aqueous film forming foams or detergents. In the context with their worldwide use and their long persistance in the environment their concentrations also have been detected in remote areas without direct surrounding sources including plants, animals and humans. PFAS concentrations in surface water and groundwater range from tens of ng/l, in the case of strong point sources to hundreds of ng/l. In the seas and oceans, PFAS concentrations are most often in the tens of pg/l due to dilution. The 2 most frequently discussed substances, perfluorooctanoic acid and perfluorooctanesulfonate, have been classified as a persistent organic pollutants because of their negative effects on human health. However, based on toxicological studies, many other substances in this group also appear to be toxic so some countries have set recommended limits for their reduction. Drinking waters have concentrations in the order of units up to tens of ng/l and therefore generally do not exceed the recommended values. However, in the area of point source of pollution, PFASs values are strongly elevated and therefore their identification and subsequent...
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Possibilities of removing metals from drinking water sources by water treatment processes
Marzinová, Kristýna ; Látal,, Milan (referee) ; Biela, Renata (advisor)
In my diploma thesis I focused on the issue of metals, their occurrence in drinking water sources in the Czech Republic and the possibility of their removal by water supply processes. Heavy metals degrade the quality of water resources, so more complex water treatment technologies are needed. The first part describes the metals, their properties, their significance and occurrence in water, then the possibility of removing metals using water supply processes. In the practical part of the diploma thesis I performed a laboratory experiment to remove iron, manganese and nickel by adsorption on selected filter materials, which are Filtrasorb F100, Filtrasorb F 400, Bayoxide E33 and GEH. The experiment was used to compare the effectiveness of selected sorption materials.
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Haloacetic acids in drinking water
Poslušná, Markéta ; Načeradská, Jana (advisor) ; Barešová, Magdalena (referee)
Chlorination byproduct occur during water disinfection. These by-product are formed by the reactions between disinfectants and natural organic matter. High concentration od natural organic matter require higher doses of oxidizing agent, which increases the formation of chlorination byproduct. Chlorination byproduct pose health risk so they must be eliminated. This work researches focuses on the occurence of chlorination byproduct in several countries and evaluates the suitability of limits concentrations. The literary research has shown that there are currently not many studies about monitoring the occurence of chlorination byproduct. If these studies exist, they are often old and therefore i tis not possible to rationally assess the quality of drinking water in term of the occurrence of chlorination byproduct. Trichloracetic acid, dichloracetit acid and dibromacetic acid are mainly important from the health point of view. The are identifield as possible carcinogens. Higher concentrations of dichloracetic acid and trichloracetic acid were observed in most studies. The result of the studies show that the highest concentration of haloacetic acid were recorded in the cities of Cherepovets (Rusia), Athens (Greece), Warsaw (Poland) and Findland. Concentrations of haloacetic acid did not exceed the limit...
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Coagulation of organic matter produced by phytoplankton
Načeradská, Jana
This dissertation thesis focuses on the removability of algal organic matter (AOM) by coagulation during water treatment and also on the influence of AOM on the coagulation of other substances present in source water. Special emphasis is put on the description of coagulation mechanisms. The effectiveness of AOM removal by coagulation was investigated by coagulation tests performed with optimized doses of coagulants (aluminium or ferric sulphate) under different pH values. Peptides and proteins contained in cellular organic matter of cyanobacterium Microcystis aeruginosa were used in the experiments since they have been previously reported to disturb the coagulation process. Moreover, peptides and proteins underwent coagulation experiments together with kaolin particles, representing clay particles in turbid waters, in both the presence and absence of coagulants to investigate the effect of AOM on the coagulation of turbid waters. To enable the description of coagulation mechanisms, AOM were characterised in terms of charge, functional groups, molecular weight and ability to form dissolved complexes with coagulant metals. The experimental results demonstrated that the removability of peptides and proteins is greatly dependent on pH value and on the properties of the involved particles or molecules....
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Adsorption of organic compounds onto activated carbon in water treatment process
Kopecká, Ivana
The dissertation thesis focuses on the application of activated carbon for the removal of low molecular weight algal organic matter (AOM) produced by phytoplankton during drinking water treatment, as well as on the effect of AOM on adsorption of anthropogenic micropollutants contained in raw water. The results of this study have been published in international peer-reviewed journals in 4 papers and in 2 conference contributions. The efficiency of AOM removal was studied in laboratory equilibrium and kinetic experiments using different types of granular activated carbon and cellular peptides with molecular weight < 10 kDa produced by cyanobacterium Microcystis aeruginosa. It has been previously confirmed that these peptides are removed with difficulty during the conventional water treatment based on coagulation/flocculation processes and therefore, other methods need to be applied for their restriction. The effect of solution properties on peptide adsorption was assessed by the tests at different pH values and at variable ionic strengths. The negative impact of peptides on the adsorption of organic micropollutants present in raw water was simulated using competitive adsorption experiments with herbicides alachlor and...
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