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Progressive methods for waste water treatment
Doležalová, Adéla ; Konečná, Eva (referee) ; Vondra, Marek (advisor)
This bachelor thesis contains a description of progressive separation methods for wastewater treatment. It deals with the basic principles of separation methods, including membrane processes, sonolysis, ozonization, photolysis and photocoalysis. Their strengths and weaknesses are also described. Part of the thesis is also evaluation and comparison of individual technologies with regard to their practical applicability.
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Degradace organických znečišťujících látek ve vodě nízkoteplotním plazmatem na bázi pokročilých procesů
BALAKRISHNAN, Syam Krishna
Water pollution by organic contaminants and other anthropogenic substances is one of the major global problems nowadays. The aquatic contaminants include pesticides, pharmaceuticals and personal care products (PPCPs), steroid hormones and synthetic dyes. Traditional processes such as UV irradiation at disinfection doses, coagulation, flocculation, precipitation, microfiltration and ultrafiltration are ineffective for the complete removal of organic contaminants in water, whereas the so called advanced oxidation processes (AOPs) are very effective in the oxidation of numerous organic compounds. The most widely used AOPs include heterogeneous photocatalysis based on near UV or solar visible irradiation, electrolysis, the Fenton's reaction, ozonation, ultrasound and wet air oxidation. AOPs are based on the generation of highly reactive hydroxyl radicals (oOH), which will attack the organic pollutants. However, the lifetimes of these radicals are so short to utilize them effectively. Therefore, the direct radical generations by non-thermal plasmas are widely researched. Three different types of plasma discharges (Dielectric Barrier Discharge, DBD, Gliding Arc Discharge, GAD, and Electrohydraulic Spark Discharge, ESD) were applied to investigate the degradation kinetics of the target pollutants in water. Firstly, the degradation of atrazine, verapamil and hydrocortisone was conducted successfully in the DBD reactor. After 90 min DBD treatment all the target pollutants were almost completely removed. Presence of the intermediates was confirmed by HPLC/UV analysis. The efficiency of dielectric barrier discharge on the degradation of atrazine and hydrocortisone was investigated. Atrazine was almost completely degraded after 90 min DBD treatment. The rate constant of this process was 0.029 min-1 and the corresponding half-life time was 24 min. After 90 min treatment time 54% of the atrazine was converted to CO2. Hydrocortisone was also completely degraded after 90 min DBD treatment. The rate constant of this process was 0.050 min-1 and the corresponding half-life time was 14 min. After five hours of treatment 21% of the hydrocortisone was converted to CO2. Structure of the intermediates was identified by HPLC/MS analysis. Plausible mechanisms for the degradation of target pollutants were also proposed. Degradation kinetics and degradation mechanism of verapamil in water under GAD was investigated. In the final part, the degradation kinetics of verapamil and atrazine by using electrohydraulic spark discharge and ozonation was investigated. During spark discharge, 87% of verapamil and 83% of atrazine were degraded within 40 min. The rate constants of the degradation processes were 0.065 min-1 and 0.094 min-1 for verapamil and atrazine respectively. The power introduced in the discharge was 60 W and is very low compared to the power of GAD. As a result, relatively high energy yields 5.1 × 10-2 g/kWh and 2.3 × 10-2 g/kWh were achieved for verapamil and atrazine respectively. Verapamil was completely removed by ozonation within 1.5 min., while atrazine was almost completely removed within 4 min. The rate constants of the degradation processes were 2.56 min-1 and 0.769 min-1 for verapamil and atrazine respectively. The power applied during ozonation was very low (20 W), compared to plasma discharges, leading to high energy yields 9.4 g/kWh and 1.6 g/kWh for verapamil and atrazine respectively. The degradation kinetics of verapamil and atrazine in water under DBD, GAD, ESD and ozonation were compared. The shortest half-lives of verapamil and atrazine were observed during ozonation. So, we can say that among our AOP systems, ozonation is the most efficient in degrading verapamil and atrazine in water.
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Reuse of treated wastewater in paper and textile industry
Matysíková, Jana ; Vachovec, Roman (referee) ; Hlavínek, Petr (advisor)
This thesis deals with Advanced oxidation processes (AOP) and its aplication for textile wastewaters treatment and reuse. AOP is a modern technology which currently recieves increased attention due to it´s high efficiency in removing resistant and hardly-degradable pollution. Thesis consists of search and practical part. Search part is created by three chapters. First chapter describe briefly wastewater reuse. The second chapter deals with Advanced oxidation processes. AOP principle, AOP division and descriotion is included with the strong focus on the ozonation technology. The third chapter presents the textile industry and its wastewaters. The practical part of this thesis consists of two chapters. Chapter 5 describes testing of textile wastewaters decoloration by ozonation in the selected textile copany and its results. This results are used in chapter 6. Chapter 6 is the study of textile industry treatment and reuse in the selected textile company. This study contains the design of two options for wastewater treatment and reuse in the textile processes.
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Utilisation of ozone for wastewater treatment
Hásová, Eva ; Dřímal,, Jiří (referee) ; Derco, Ján (advisor)
Diploma thesis will be dealt with the utilization of ozone wastewater treatment. Experimental part will be focused on study of ozone utilization in two different reactors (bubble column, jet loop reactor). Reactors will be compared by overall mass transfer coefficient and saturation concentration. Ozonization will be applied because of biological resistent and toxic compound 2-mercaptobenzothiazole disposal. Changes of biological decomposition will be measured and assessed by respirometric measurements.
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The problems of fenol sorption from waste water
Židek, Michal ; Pavlovský,, Jiří (referee) ; Doležalová Weissmannová, Helena (advisor)
The bachelor work deals of sorption of phenol from waste water. In theoretical part the basic characteristic of phenol, their effects and presence in environmental compounds are described. The possibility of removal phenol from waste water in waste water treatment is also described. The adsorption process of removal phenol introduced too. The analysis current adsorbents using in removal phenol from aqueous solutions and characteristic properties are also presented in relation to materials on the base of clay minerals. The experimental part is focused on the possibility of removal phenol from aqueous solution via adsorption mechanism under various pH conditions.
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Problems of phenols in water
Tylichová, Petra ; Čáslavský, Josef (referee) ; Doležalová Weissmannová, Helena (advisor)
This bachelor`s thesis deals with the issue of phenols in the waters. The theoretical part summarises the information about the characteristics of the phenols, its use, appearance in the environment, and its effects on human health. There are described methods of determination these substance in the waters. The last chapter disserts on possible methods of eliminating the phenols from the aqueous environment with special attention paid to the adsorption method. Part of this thesis is also dedicated to the chlorinated phenols which originate from chlorination of the phenolic waters and which cause the sensory interferences of the waters. The experimental part of this thesis is dedicated to removing the phenol from a model water through the adsorption into a powdery active carbon Norit SA SUPER.
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