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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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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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