Optimizacija naprednih oksidacijskih postopkov pri oksidaciji organskih spojin v postopkih priprave pitne in bazenske vode : doktorska disertacija

Čehovin, Matej (author), Kompare, Boris (mentor), Žgajnar Gotvajn, Andreja (comentor)

Cilji raziskovalnega dela so bili preučiti, ali sklopitev naprednih oksidacijskih postopkov na osnovi ozona (O3), vodikovega peroksida (H2O2) in UV svetlobe, med seboj in s hidrodinamično kavitacijo, izboljša učinkovitost odstranjevanja tarčnih onesnažil ter zmanjša potrebne količine reaktantov in energije na enoto odstranjenega onesnažila pri oksidaciji organskih snovi iz pitne in bazenske vode v sistemih v povečanem merilu. Pri tem smo zasledovali vplive spreminjanja karakterističnih obratovalnih parametrov na učinke odstranjevanja izbranih naravnih in sintetičnih organskih onesnažil, s poudarkom na doseganje učinkov v reakcijskih časih do 20 min. Pri raziskovalnem delu smo se osredotočali na postopke ozoniranja in napredne oksidacije s kombinacijami H2O2/O3, H2O2/UV ter O3/UV. Kot mehanizem za optimizacijo procesa, smo naštetim naprednim oksidacijskim postopkom dodali stopnjo s hibridno hidrodinamično kavitacijo. Eksperimentalno delo se je izvajalo na polkontinuirni testni napravi s prostornino 50%83 L, da bi se čim bolj približali pogojem obratovanja sistemov v polnem merilu. Na podlagi izvedene raziskave lahko potrdimo hipotezo, da je s sklopitvijo napredne oksidacije na osnovi O3, H2O2 in UV svetlobe ter hibridne hidrodinamične kavitacije v sistemih v povečanem merilu možno dosegati boljše učinke odstranjevanja tarčnih onesnažil oz. te učinke dosegati pri nižjih dozah uporabljenih oksidantov. Dodatno smo potrdili možnost doseganja ugodnih učinkov uporabe hibridne hidrodinamične kavitacije z majhnimi števili prehodov skozi generatorje le-te (3%12) in v reakcijskih časih do 20 minut. Hibridna hidrodinamična kavitacija, uporabljena na način, ki je predstavljen v tej disertaciji, je lahko v določenih primerih vsaj toliko ali celo bolj energetsko učinkovita, kot samostojni postopki napredne oksidacije na osnovi O3, H2O2 in UV svetlobe. Navedeno velja predvsem, ko so razmerja med dozami oksidantov ter UV svetlobe in koncentracijami tarčnih onesnažil v vzorcih relativno nizka. Potrdili smo, da je potrebno nameniti stranskim produktom napredne oksidacije in stranskim produktom tovrstno že pripravljene pitne in bazenske vode pri naknadni oksidaciji in dezinfekciji s klorom, še posebej v primeru uporabe hibridne hidrodinamične kavitacije.

• Language: Slovenian
• Keywords: grajeno okolje, gradbeništvo, disertacije, bazenska voda, hidrodinamična kavitacija, napredna oksidacija, ozon, pitna voda, UV svetloba, vodikov peroksid
• Work type: Doctoral dissertation
• Typology: 2.08 - Doctoral Dissertation
• Organization: FGG - Faculty of Civil and Geodetic Engineering
• Publisher: [M. Čehovin]
• Year: 2017
• PID: 20.500.12556/RUL-99218
• UDC: 628.16:66.094.3(043)
• COBISS.SI-ID: 8200545
• Publication date in RUL: 08.01.2018

Licences

• License: CC BY-NC 4.0, Creative Commons Attribution-NonCommercial 4.0 International
• Link: http://creativecommons.org/licenses/by-nc/4.0/
• Description: A creative commons license that bans commercial use, but the users don’t have to license their derivative works on the same terms.
• Licensing start date: 08.01.2018

Secondary language

• Language: English
• Title: Optimization of the advanced oxidation processes for oxidation of organic substances for drinking and swimming-pool water treatment : doctoral dissertation

Abstract

The objectives of this research were to assess the effects of hybrid hydrodynamic cavitation on advanced oxidation processes based on ozone (O3), hydrogen peroxide (H2O2) and UV light for drinking and swimming-pool water treatment. Attention was paid to the changes in the removal efficiency of the target pollutants and specific energy consumption to achieve the same order of target pollutant removal. Changes of the characteristic operational parameters were more closely followed. The reaction times up to 20 minutes were considered preferential. Ozonation alone and the combinations of H2O2/O3, H2O2/UV and O3/UV advanced oxidation processes were applied in the experiments. As a mechanism of the process optimization, hybrid hydrodinamic cavitation was added to the process. The experimental setup was designed as a semi-batch scale-up system and utilized the reaction volumes of 50%83 L. Based on the obtained results we could confirm that the application of the hybrid hydrodynamic cavitation, under the applied experimental conditions, was able to improve the efficiency of treatment by ozone, H2O2/O3 and H2O2/UV advanced oxidation processes. Further, conditions of low number of passes through the system (3%12) were sufficient to exploit the beneficial effects of hybrid hydrodynamic cavitation and the reaction times up to 20 minutes were proven to be sufficient. Under herein described experimental conditions, the application of hybrid hydrodynamic cavitation could in some cases be at least as energy efficient as the O3, H2O2 and UV based advanced oxidation processes alone. These results were most evident when the ratios between the dosages of the applied oxidants or UV light and concentrations of the target pollutants in the samples were relatively low. Special attention needs to be paid to the formation of the by-products of the advanced oxidation processes. This is of yet greater importance when previously treated drinking or swimming-pool water is subjected to subsequent oxidation or disinfection by chlorine and especially if hybrid hydrodynamic cavitation is applied together with the advanced oxidation processes.

• Keywords: building environment, civil engineering, thesis, advanced oxidation, drinking water, hydrodynamic cavitation, hydrogen peroxide, ozone, swimming-pool water, uv light