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Danylo, Félix. "Treatment of ibuprofen containing industrial first wash-water by ozonation, sonication, ozonation/H2O2 ozonation/sonication and sonication/H2O2." Thesis, McGill University, 2011. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=97256.
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Ibuprofen (IBP) is one of the most prescribed drugs. It has been shown that IBP resist physicochemical wastewater treatment (Gagnon and Lajeunesse 2008). Also, IBP has a known negative effect on algae (Brown et al. 2007). This research focused on removal of aqueous IBP using five different oxidative techniques: ozonation, ozonation with hydrogen peroxide, ozone with sonication, sonication with hydrogen peroxide and sonication alone. IBP and chemical oxidation demand (COD) removals were monitored for experiments performed over a range of operating conditions: pH (4 to 7), temperature (5 to 25ºC), applied ozone dose (8 to 16 mg/L) and applied power 5 watts. Solutions of 5 mg/L IBP were treated in a custom-designed semi-continuous 900-mL reactor. The design allowed the application of ozone and ultrasounds from the bottom of the reactor either separately or simultaneously. A synergic effect was observed for the combined treatment O3/sonication. This might be explained by the higher mass transfer of ozone in the solution observed in presence of ultrasounds. Although H2O2 significantly increased the IBP removal when used in combination with O3, the addition during sonication did not result in increased IBP removal. Four transformation products were detected as new peaks on the HPLC chromatograms. Oxo-ibuprofen, 4-acetylbenzoic acid, 4-ethybenzaldehyde and oxalic acid were identified as products using LC/MS. COD analyses indicated low degrees of mineralization in the range of 11 to 41%. The highest IBP and COD removals of 95% and 41% were obtained with O3/H2O2 performed at 15ºC and pH 7. Optimized parameters for each technique were applied to IBP contained in first wash-water produced at an ibuprofen processing plant (Wyeth, St-Laurent, Quebec, Canada). The industrial first wash water had an IBP concentration of 582ppm. All experiments with first-wash-water were compared to results obtained in a synthetic solution of equivalent IBP concentration in pure water. For all oxidation techniques, a higher IBP removal was obtained in the wash-water and the highest IBP removal of 16% was obtained with O3/H2O2. To the author's knowledge, this project was the first study comparing all these techniques and considering the treatment of first wash-water of an industrial plant.<br>L'ibuprofène (IBP) est un des composés pharmaceutiques les plus prescrits. L'IBP résiste au traitement physico-chimique des eaux usées (Gagnon and Lajeunesse 2008). L'IBP a également été identifié comme ayant des effets négatifs sur des algues (Brown et al. 2007). Cette recherche s'est concentrée sur l'élimination de l'IBP aqueux par cinq techniques d'oxydation dont l'ozonation, l'ozonation couplée au peroxyde d'hydrogène, l'ozonation couplée à la sonification, la sonification couplée au peroxyde d'hydrogène et la sonification seule. La diminution d'IBP et la demande chimique en oxygène ont été déterminées pour chaque technique oxydative opérées sous les paramètres d'opération suivants : pH (4 à 7), température (5 à 25ºC), dose d'ozone (8 à 16 mg/L) et puissance de sonication (0-5 Watts). Une solution de 5 ppm d'IBP a été traitée dans un réacteur semi continu de 900 mL conçu pour ce projet. Le design de ce réacteur permet au bas du réacteur l'alimentation d'ozone et l'émission d'ultrasons, séparément ou simultanément. Un effet synergique a été observé lorsque l'ozone est combiné à la sonification. Cette synergie peut être expliquée par l'augmentation du transfert de masse de l'ozone dans la solution due au champ d'ultrasons. L'ajout de H2O2 a augmenté significativement l'élimination d'IBP lorsque combiné avec l'ozone. L'addition durant la sonification a démontré aucun effet. Quatre produits de transformation ont été identifiés par LC/MS : oxo-IBP, acide 4-acetylbenzoïque, 4-athylbenzaldehyde et l'acide oxalique. Les analyses de COD ont indiqué un degré de minéralisation allant de 11 à 41%. L'élimination la plus significative d'IBP et de COD a été de 95% et 41%, obtenu lors du traitement avec l'O3/H2O2 à une température de 15ºC et un pH de 7. Les paramètres optimaux pour chaque technique d'oxydation ont été appliqués à une eau de premier lavage d'un procédé industriel de comprimés d'ibuprofène fourni par Wyeth, St Laurent, Québec, Canada, ayant une concentration d'IBP de 582 ppm. Une plus grande élimination d'IBP a été obtenue dans l'eau de lavage comparativement à une solution synthétique de même concentration et ce, pour chaque technique étudiée. La plus importante élimination d'IBP dans l'eau de lavage, d'une valeur de 16%, a été obtenue avec le traitement d'O3/H2O2. Selon l'auteur, cette étude constitue une première comparaison systématique de ces techniques et la première étude du traitement d'une première eau de lavage industrielle.
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Falcão, Dantas Renato. "Ozonation of Emergent Contaminants." Doctoral thesis, Universitat de Barcelona, 2007. http://hdl.handle.net/10803/1534.
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ENGLISH SUMMARY:<br/><br/>In this work, the ozonation of emergent contaminants represented by pharmaceuticals (Sulfamethoxazole and Bezafibrate) and surfactants (Quaternary Ammonium Compounds) was studied. Results in terms of target compound degradation and mineralization along with the biodegradability and toxicity assessment of formed intermediates are presented. Moreover, a previous study about the suitability of the combination ozonation-Sequencing Batch Biofilm Reactor (SBBR), using the model compound 4-chlorophenol, is shown. <br/><br/>The preliminary runs aimed to assess the mineralization of 100 and 200 mg L-1 4-chlorophenol (4-CP) solutions by ozonation and ozonation-biological treatment (SBBR). The experimental results showed that with an ozone flow rate of 5.44 and 7.57 g h-1, 4-CP was completely removed from the solution in 15 and 30 minutes of ozonation, respectively. By the other hand, at the 4-CP abatement time, on average only 26 % of total organic carbon (TOC) removal was achieved. The biodegradability (BOD5/COD) of the pre-ozonated solutions increased from 0 until a range between 0.2-0.37. The combination of ozonation and aerobic biological treatment in an aerobic sequencing batch biofilm reactor (SBBR) gave an abatement of more than 90 % of the initial TOC.<br/><br/>The Quaternary Ammonium Compounds (QACs) ozonation was carried out in order to assess the mineralization potential of ozonation processes for this class of compounds. To perform this study, the QACs 16-BAC (Benzyl-dimethyl-hexadecylammonium-chloride) and 18-BAC (Benzyl-dimethyl-stearylammonium-chloride) were treated by ozonation at different O3 dosage. According to experimental results, from an initial TOC concentration of 50 mg L-1, 90 minutes of ozonation reached at most 50% of mineralization at the used conditions (ozone flow rate 7.57 g h-1). In order to observe the mineralization of QACs by means of photo-Fenton, the runs were carried out with the same QAC concentration used in ozonation runs. Besides, two different lamps were used (UV and Xe). According to experimental results, after 90 minutes of treatment, the photo-Fenton process achieved up to 80% of mineralization when the UV lamp was used. The efficiency of the photo-Fenton with Xe lamp was lower.<br/><br/>To carry out the study of the sulfamethoxazole (SMX) ozonation, 200 mg L-1 SMX solutions were treated by ozonation at different pH. Results showed that ozonation was proved to be an efficient method to degrade sulfamethoxazole. After 15 minutes of ozonation (corresponding dose = 0.4 g of ozone L-1), the complete antibiotic abatement was almost achieved with just 10 % of mineralization. The biodegradability and toxicity of the ozonation intermediates were also studied. A biodegradability enhancement (increment of BOD5/COD ratio) from 0 to 0.28 was observed after 60 min of ozonation. The acute toxicity of the intermediates was followed by the Microtox® test and the toxicity profile showed a slight acute toxicity increment in the first stage of ozonation. The second order kinetic constants for the ozonation of the SMX in an order of magnitude of 105 L mol-1 s-1 were also determined for pH 5 and 7.<br/><br/>Concerning the Bezafibrate (BZF) ozonation, the results showed that ozonation is an efficient method to degrade BZF: after 10 minutes of treatment (corresponding to a dose of 0.73 mmoles L-1 of ozone), the complete BZF abatement is achieved, starting from an initial concentration of 0.5 mmoles L-1. However, only a small part of the substrate is mineralized. The identification of main intermediates, attempted by HPLC-MS technique, indicates that the oxidation of BZF develops through both the hydroxylation of the aromatic ring and the attack of ozone on the unchlorinated aromatic one. The assessment of by-products biodegradability and acute toxicity demonstrates that ozonation is a suitable technique to improve the biodegradability and reduce the toxicity of waters containing BZF.
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Allemane, Hélène. "Oxydation de quelques composés organiques en milieu aqueux par ozonation et ozonation catalytique." Poitiers, 1994. http://www.theses.fr/1994POIT2285.
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Ce travail a eu pour objectifs, d'une part d'eprouver l'efficacite de l'ozonation et de l'ozonation combinee vis-a-vis de divers composes organiques, d'autre part de contribuer a la connaissance des sous-produits d'oxydation par le systeme o#3/h#2o#2 de quelques pesticides. A ph legerement basique ( 8), en l'absence de pieges a radicaux et en reacteur semi-continu, l'efficacite de l'ozonation seule, de la perozonation (o#3/h#2o#2 ; rapport molaire h#2o#2/o#3 = 0,4 g/g) et de la catazonation (o#3/catalyseur a base de tio#2) vis-a-vis des pesticides est comparable. En revanche, dans ces memes conditions, pour la plupart des molecules organiques (acides simples, acides fulviques aquatiques, proteine, hydrate carbone), l'ordre d'efficacite o#3 < o#3/h#2o#2 < o#3/catalyseur semble se degager. Toutefois, la capacite adsorbante du catalyseur utilise minimise sensiblement l'efficacite du procede catalytique. L'oxydation du lindane, du metolachlor, du mecoprop et de l'isoproturon par le couplage o#3/h#2o#2 conduit dans tous les cas a une mineralisation limitee du carbone organique et a une dechloration complete. Les premiers sous-produits identifies indiquent que les reactions portent essentiellement sur les liaisons c-h des groupements les plus accessibles de la molecule, mais egalement sur la liaison c-n dans le cas de l'isoproturon, conduisant a la formation de composes oxygenes (fonctions alcools, carbonyles). Les composes detectes sont: un dichloro- et un trichlorochlorophenol (lindane), l'oxo metolachlor et des composes cyclises (metolachlor), le 2-methyl-4-chlorophenol et des 2-methyl-4 chlorophenylesters (mecoprop), des composes phenyles et/ou azotes divers (isoproturon)
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Kim, Ree-Ho. "Analysis of Inactivation Mechanism of Cryptosporidium parvum by Ozonation and Evaluation of Ozonation Performance." Kyoto University, 2000. http://hdl.handle.net/2433/151528.
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Leclair, Christine. "Ozonation of sulfamethoxazole in wastewater." Thesis, McGill University, 2006. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=99776.
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Many studies have demonstrated that sewage treatment plants do not efficiently degrade pharmaceuticals such as antibiotics, hormones, and analgesics. Ozonation has been identified as a promising technique to degrade those compounds. A series of experiments was used to evaluate the impact of three parameters on the efficiency and kinetics of degradation of sulfamethoxazole, an antibiotic, by ozonation. An ozone reactor was designed to perform experiments. Analytical techniques, based on liquid and gas chromatography and mass spectrometry, were developed to measure concentrations of sulfamethoxazole and identify degradation products.<br>It was shown that the rate constant and the degradation efficiency are greater when the initial concentration of sulfamethoxazole is lower; the presence of other contaminants in solution decreases the percentage of degradation observed, and the concentration of hydrogen peroxide, used as catalyst, must be well adjusted since an inappropriate concentration hinders the reaction. Finally, the analysis of ozonated samples allowed the identification of degradation products and resulted in a proposed degradation mechanism.
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Rodayan, Angela. "Ozonation of sulfamethoxazole in municipal wastewater." Thesis, McGill University, 2009. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=40763.
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Many pharmaceuticals, such as the antibiotic sulfamethoxazole, are not eliminated during a conventional wastewater treatment process and are often not biodegraded in the environment. In this project, 60 mg/L and 100 μg/L solutions of sulfamethoxazole in both reverse osmosis water and wastewater were treated with ozone. A solid phase extraction procedure with reproducible analyte recoveries was developed to pre-concentrate the low concentration of sulfamethoxazole in both water matrices (reverse osmosis and municipal wastewater). The wastewater matrix had no effect on the required ozone dose to reduce the concentration of sulfamethoxazole below the SPE-HPLC limit of detection. Solutions with an initial concentration of 60 mg/L required an ozone dose of 331 mg/L and eight peaks were detected throughout experiments. Solutions with an initial concentration of 100 μg/L required a dose of 55 mg/L and only four peaks were detected. Analysis of the degradation products showed that 4-aminobenzene sulfonamide, N-(3-phenylpropyl)-acetamide, 2-methyl-benzoxazole and phenol were present in both high and low concentration samples. In addition, methanol, ethanol, acetic acid, methyl acetate and ethyl acetate were present in the high concentration samples.<br>Plusieurs pharmaceutiques, tel que l’antibiotique sulfaméthoxazole ne sont pas totalement éliminées lors du traitement des eaux usées et ne sont pas biodégradables dans l’environnent. Au cours de ce projet, deux types de solutions de sulfaméthoxazole ont été étudiées : à base d’eau traitée par osmose inverse et à base d’eau usée municipale. Des solutions ayant des concentrations de 60 mg/L et 100 μg/L ont été traitées par ozonation.Une méthode d’extraction en phase solide a été développée afin de préconcentrer les échantillons avant l’analyse par HPLC. Les solutions de sulfaméthoxazole composées d’eau traitée par osmose inverse et d’eau usée ont requis la même quantité d’ozone afin de réduire la concentration de sulfaméthoxazole sous la limite de détection du HPLC. Les solutions avec une concentration initiale de 60 mg/L ont requis une dose d’ozone de 331 mg/L et huit produits de dégradation ont été détectés. Les solutions ayant une concentration initiale de 100 μg/L ont requis une dose de 55 mg/L et seulement quatre produits de dégradation ont été détectés. L’analyse des produits de dégradation a démontré que le 4-aminobenzène sulfonamide, N-(3-phenylpropyl)-acetamide, 2-méthyl-benzoxaole et le phénol sont présents dans les solutions de faible et haute concentration initiale en sulfaméthoxazole. De plus, le méthanol, l’éthanol, l’acide acétique, l’acétate de méthyle et l’acétate d’éthyle sont ont été détectés dans les solutions de haute concentration.
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Steele, Andrew Michael. "The catalytic ozonation of industrial wastewaters." Thesis, University of Reading, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.428198.
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Marcé, Escalé Mireia. "Ozonation of Municipal Wastewater for Water Reuse." Doctoral thesis, Universitat de Barcelona, 2017. http://hdl.handle.net/10803/402548.
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Water is essential for life in all the levels: humans, animals and plants depend on it for their existence. The unsustainable growth, the changes in the consumption pattern and the climate change have positioned water resources under pressure. In this scenario where the water quality and quantity are a worldwide concern, research and development have analyzed and generated various emerging technologies that can promote the use of alternative sources of water.
Commonly, the Municipal WWTPs are organized in four stages that include physical, chemical and biological processes. Wastewater treatment plants (WWTPs) will have an important role in the future eco-cities since will provide energy by means of a system characterized by the smallest possible ecological footprint. However, several ecological effects have been observed downstream of WWTP outfalls, probably due to the incomplete removal of pollutants by the conventional WWTPs. The analysis and understanding of the pollutants fate in Conventional WWTPs is fully necessary to create measures to reduce their release in the environment.
Even though, conventional WWTPs are designed to treat solid wastes, suspended solids and biodegradable dEfOM, many micropollutants are also affected by the treatment train. Hence, half of the micropollutant load is eliminated either by sorption to the sludge, biological degradation, volatilization and abiotic degradation. Despite this fact, some hydrophilic compounds are neither adsorbed into the sludge nor eliminated in the discharge effluents. Consequently, some of these micropollutants can end up in the aquatic environment generating negative effects, including long-term and short-term toxicity.
In the problematic water pollution scenario mentioned before, advanced oxidation processes (AOPs) emerge as a possible alternative to treat the biologically persistent wastewater improving water quality and therefore restoring the aquatic environment. These processes degrade organic pollutants by forming hydroxyl radicals (OH·) which are highly reactive and non- selective. Nowadays, AOPs include also the processes that involve other radicals as sulfate radicals (SO4 ·).
Ozone application is used in wastewater, disinfection and air treatment to minimize the pollution. This process has two main strengths: on one hand, the strong oxidant potential and secondly, the lack of residues after its application. Ozone can react directly, via molecular pathway or indirectly via hydroxyl radical.
In this work, ozone has been applied to different non-conventional points of the treatment line, to check if its action could promote the enhancement of the whole treatment. Thus, it has been applied at the outlet of the primary effluent leading us to an improvement in the water quality parameters and in the removal of micropollutants. Moreover, other significant parameters for ozone application as the ozone demand and mass transfer have been studied.
Afterwards, the study was focus in the application of ozone on the activated sludge matrix. In this case, ozone showed good performance too, improving the settleability, increasing the solubility of sludge and eliminating micropollutants in both phases (sludge and supernatant).
Finally, the combination of ozone application with biological treatments was tested. Thus, ozone was applied to the primary effluent which was lately treated by an aerobic biological treatment.
In this case, good performances were observed at the level of micropollutants. Lately, ozone was applied to the conventional activated sludge matrix which was subsequently introduced in an anaerobic process to check the enhancement of biogas production. In this case, only two ozone doses showed better performances than the initial sludge without ozone pretreatment. Biodegradability and acute toxicity was studied for the primary effluent before and after ozonation, showing an improvement when the transfer ozone dose increased.<br>L’aigua es essencial per la vida en tots els nivells: humans, animals i plantes depenen d’ella per la seva pròpia existència. El creixement insostenible, els canvis en el patró de consum i el canvi climàtic han situat els recursos hídrics sota pressió. En aquest escenari on la qualitat de l’aigua i la quantitat són una preocupació mundial, la recerca i el desenvolupament analitzen actualment les tecnologies que promoguin el ús alternatiu dels recursos hídrics.
En l’escenari de la problemàtica de l’aigua, els processos d’oxidació avançada emergeixen com a possible alternativa per tractar els compostos recalcitrants que trobem en l’aigua, millorant la qualitat de l’aigua i per tant, restaurant el medi aquàtic. Aquests processos, degraden els contaminants orgànics formant radicals hidroxils (·OH) que són altament reactius i no són selectius.
L’ozó s’utilitza en el tractament d’aigües residuals, desinfecció i tractament de l’aire per minimitzar la contaminació. Aquest procés té dos punts forts: per una banda, el fort potencial oxidant i en segon lloc, la manca de residus després de la seva aplicació. L’Ozó pot reaccionar directament, via molecular o indirectament via el radical hidroxil.
En aquest projecte, l’ozó s’ha aplicat a diferents punts de la cadena de tractament, per tal de comprovar si la seva acció pot promoure una millora en el tractament global. Així, s’ha aplicat a l’efluent de la sortida del tractament primari millorant els paràmetres de l’efluent primari tant a nivell de la qualitat de l’aigua i de l’eliminació dels microcontaminants. A més, altres paràmetres importants relacionats amb l’aplicació de l’ozó i la demanda d’ozó han estat estudiats.
Després, l’estudi es va centrar en l’aplicació de l’ozó en una matriu de Fangs Activats. En aquest cas, ozó va mostrar bons resultats millorant la sedimentació, incrementant la solubilitat dels fangs i l’eliminant els microcontaminants.
Finalment, l’ozó es va combinar amb tractaments biològics, aeròbics i anaeròbics. Bones eliminacions es van observar a nivell de microcontaminants. Tot i així, només dues dosis van afavorir una millora en la producció del biogàs.
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Hung, Isaac, and Isaac Hung. "Ultrafine Bubble-Enhanced Ozonation For Water Treatment." Thesis, The University of Arizona, 2016. http://hdl.handle.net/10150/621853.
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Ultrafine bubbles, often referred to as nanobubbles, have been used in various applications from environmental remediation to medicine. Even though the technology to generate ultrafine bubbles has been around for many years, the full potential of its applications has not been completely studied. This project seeks to study the use of ultrafine bubble technology for water treatment in combination with ozone gas. A factorial design experiment was chosen to test the effects of ultrafine bubbles on the concentration of an indicator organism, E. coli, in water as well as their effects on ozone gas being injected into water. Ozone gas or nitrogen gas was injected into water contaminated with E. coli as either ultrafine bubbles or fine bubbles as treatments for up to 60 minutes. Ultrafine bubbles were found to not have any significant effect on the concentration of E. coli in water. However, ultrafine bubbles did provide benefits when used in conjunction with ozone gas that regular, fine bubbles did not provide. The benefits included allowing the concentration of dissolved ozone in the water to decrease at a slower rate as well as allowing more ozone to dissolve into water at a higher rate than conventional methods of bubbling in ozone. While in this particular set of experiments the concentration of dissolved ozone in water didn't surpass 2 mg/L, which didn't allow for rapid disinfection and treatment of water, it is believed that with a more powerful ozone generator better results can be achieved. This project demonstrates the benefits and potential of injecting ozone gas as ultrafine bubbles into water as a way to effectively and efficiently disinfect and treat water.
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Zhang, Jie. "Numerical Simulation of Flow in Ozonation Process." Scholar Commons, 2014. https://scholarcommons.usf.edu/etd/5161.
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In the last two decades, Computational Fluid Dynamics (CFD) has shown great potential as a powerful and cost-efficient tool to troubleshoot existing disinfection contactors and improve future designs for the water and wastewater treatment utilities.
In the first part of this dissertation two CFD simulation methodologies or strategies for computing turbulent flow are evaluated in terms of the predicted hydraulic performance of contactors. In the LES (large eddy simulation) methodology, the more energetic, larger scales of the turbulence are explicitly computed or resolved by the grid. In the less computationally intensive RANS (Reynolds-averaged Navier-Stokes) methodology, only the mean component of the flow is resolved and the effect of the unresolved turbulent scales is accounted for through a turbulence model. For baffled contactors, RANS performs on par with the LES in predicting hydraulic performance indices. In this type of contactors, hydraulic performance is primarily determined by quasi-steady recirculating (dead) zones within the contactor chambers which are well-resolved in both RANS and LES. Testing of the RANS methodology is also performed for a wastewater stabilization pond leading to prediction of hydraulic performance indices in good agreement with field measurements. However, for column contactors, LES performs better than RANS due to the ability of the LES to resolve unsteady or unstable flow structure associated with spatial transition to turbulence which is important in the determination of the hydraulic performance of the contactor.
In the second part of this dissertation the RANS methodology is adapted in order to develop a novel modeling framework for ozone disinfection of drinking water. This framework is unique as it combines CFD with kinetics-based reaction modeling to predict disinfection performance and bromate formation for the first time. Bromate, a human health hazard, is an undesired by-product of the disinfection of drinking water via ozonation. The modeling framework is validated via application to a full-scale ozone contactor. Predictions of ozone and bromate concentrations are consistent with data from physical experiments.
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Da, Silva Bradley. "Development of catalytic microreactors by plasma processes : application to wastewater treatment." Thesis, Paris 6, 2015. http://www.theses.fr/2015PA066447.
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Un aspect clé permettant de surmonter les défis énergétiques et environnementaux est d'améliorer l'efficacité des nouveaux procédés. La plupart des produits chimiques majeurs se faisant par des procédés catalytiques, une meilleure compréhension des cinétiques de réaction est nécessaire. Dans le domaine du traitement des eaux usées, l'ozonation catalytique est en un exemple typique. Dans cette thèse, des microréacteurs catalytiques sont utilisés en tant qu’outils analytiques innovants afin de déterminer la cinétique de l'ozonation catalytique. Ceux-ci ont pu être élaborés à l'aide de procédés plasma en déposant et en activant un catalyseur à base d’oxyde de fer et de cobalt. L’efficacité de ces catalyseurs a été mesurée en utilisant de l'acide pyruvique en tant que polluant modèle. Pour Fe2O3, les mesures HPLC ont montré l'inactivité de celui-ci par rapport à Co3O4 (20%). Cet effet a été doublé après post-traitement par un plasma d'Ar, démontrant ainsi le rôle du plasma. Une simulation numérique portant sur les réactions à la surface du catalyseur a été réalisée en utilisant le logiciel Comsol Multiphysics. Le modèle utilisé s’est partiellement approché des données expérimentales en raison du manque de données concernant les constantes de réactions des espèces intermédiaires. Ces constantes cinétiques pourront être déterminées grâce à l'utilisation de la technique de spectroscopie Raman Anti-Stokes Cohérente (technique CARS) en tant qu’outil d'analyse en temps réel. En perspectives, l’utilisation de cette dernière conduira à l’élaboration d’un outil efficace qui pourrait prédire la pertinence et les futures stratégies d'amélioration sur des réactions chimiques catalysées<br>A key aspect in overcoming the energy and environmental challenges is to improve the efficiency of existing and new processes. Nowadays, almost all major chemicals are produced by catalytic processes. However, a better understanding of the reaction pathways and kinetics is needed. In the field of wastewater treatment, catalytic ozonation is a typical example of this problem. In this study, catalytic microreactors were used as innovative analytical tools for the determination of kinetics of catalytic ozonation and were elaborated by using low pressure plasma processes for the deposition and activation of iron and oxide-based catalysts on polymer-based materials. Catalytic ozonation with pyruvic acid as a refractory probe compound was performed with both catalysts. HPLC measurements showed the inactivity of the iron oxide layer compared to the cobalt oxide one which led to 20 % of degradation. The effect was doubled when the latter was post-treated by an argon plasma, demonstrating the role and importance of the plasma post-treatment step. A numerical study dealing with the reactions taking place on the surface of the catalyst was carried out using the Comsol Multiphysics software and showed that the model partially fitted the experimental data due to the lack of information. However, access to the reactions rate constants of the intermediate species generated during the catalytic ozonation step could be achieved through the use of the Coherent Anti-Stokes Raman Spectroscopy technique and would lead to an efficient tool to predict the relevance and the direction of future improvement strategies regarding catalyzed chemical reactions
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Morali, Eyup Kaan. "Ozonation Of A Denim Producing Textile Industry Wastewater." Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12612428/index.pdf.
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Denim production is one of the leading sub-sectors of textile industry which basically generates highly colored indigo dyeing effluents. In the present study, ozonation was applied to the indigo-dyeing effluent(COD=820 mg/L<br>color=5500 Pt-Co), and to the whole effluent from a denim-producing plant before(COD=2750 mg/L<br>color=3950 Pt-Co) and after(COD=800 mg/L,color=3700 Pt-Co) biological treatment for degradation/detoxification purposes. Ozonation was also tried in the wastewater of the plant(COD=3100 mg/L<br>color=4500 Pt-Co) that would be produced after some foreseen cleaner production measures<br>caustic recovery and reusing of dyeing process wastewater.
When applied to indigo-dyeing wastewater<br>ozonation provided 95% color and 61% COD removals at 1320 mg/h ozone dose within 60 minutes The optimum pH was evaluated as 4 when indigo-dyeing wastewater exposed to ozonation at different pHs(1.6-12.3). On the other side, ozonation applied as pre-treatment to the plant effluent provided 86% color and 46% COD removals with 3240 mg/h ozone dose in 70 minutes. Less satisfactory results were obtained when ozonation was tried in the wastewater after measures, with 86% color and 31% COD removals at 3960 mg/h ozone dose in 80 minutes. When applied to the biologically-treated effluent<br>at 420
mg/h ozone dose and within 40 minutes, ozonation removed 47% of influent COD and 96% of influent color indicating better performance of ozonation in postoxidation. In order to assess possible improvements on ozonation with the addition of H2O2, different concentrations were tried, but no significant improvement was obtained. The improvement in BOD5/COD index was also determined for the ozonetreated
plant effluent to measure the effects of ozonation on biodegradability and found out that BOD5/COD ratio has improved to 0.39 from 0.22.
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Hofmann, Ronald. "Using ammonia to inhibit bromate formation during ozonation." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0019/NQ53686.pdf.
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Bengraine, Karim. "Ozonation de solutions aqueuses : role de l'eau oxygenee." Paris 7, 1988. http://www.theses.fr/1988PA077176.
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Contribution a la meilleure connaissance des phenomenes impliques dans une filiere de traitement de l'eau, avec un interet plus particulier au role de l'eau oxygenee au cours de l'ozonation de solutions aqueuses. Etude de l'ozonation de molecules organiques (acides salicylique, phtalique et oxalique), des mecanismes mis en jeu et comparaison des produits obtenus par ozonation et par reaction de fenton
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Kwong, Chi Wai. "Catalytic ozonation of VOCS over different porous materials /." View abstract or full-text, 2009. http://library.ust.hk/cgi/db/thesis.pl?EVNG%202009%20KWONG.
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Bengraine, Karim. "Ozonation de solutions aqueuses rôle de l'eau oxygénéé /." Grenoble 2 : ANRT, 1988. http://catalogue.bnf.fr/ark:/12148/cb37611797z.
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Kim, Sung-Eun. "Removal characteristics of endocrine disrupting substances during ozonation." 京都大学 (Kyoto University), 2004. http://hdl.handle.net/2433/145367.
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Mathon, Baptiste. "Photodégradation et oxydation chimique de micropolluants pharmaceutiques et phytosanitaires en traitement complémentaire : performances, mécanismes et modélisation." Thesis, Lyon, 2016. http://www.theses.fr/2016LYSE1251/document.
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Dans le cadre de l'application de la directive cadre sur l'eau, la liste des substances « prioritaires » a été révisée et une nouvelle liste dite « de vigilance » a été récemment proposée pour des substances dont les connaissances sur l'exposition et la dangerosité sont à documenter. Or, les stations de traitement des eaux usées (STEU) domestiques actuelles, majoritairement des procédés secondaires biologiques, n'ont pas été conçues pour éliminer les micropolluants. Si elles en éliminent une grande partie, de nombreux micropolluants organiques (pesticides, composés pharmaceutiques, hormones, etc.) sont encore présents dans les eaux traitées. Certains procédés de traitement complémentaires (ou tertiaires) intensifs ou extensifs ont récemment été étudiés de façon à déterminer leur capacité à éliminer des micropolluants considérés comme réfractaires au traitement biologique (peu biodégradable ou faiblement sorbables sur les MES) et/ou présents en fortes concentrations dans les eaux usées brutes. Ainsi, l'oxydation par l'ozone ou par le peroxyde d'hydrogène, et l'adsorption sur charbon actif présentent des rendements supérieurs à 70% pour la majorité des pesticides et des pharmaceutiques étudiés. Concernant les procédés extensifs, de récentes études suggèrent que le rayonnement solaire pénétrant dans une colonne d'eau (ex. zone de rejet végétalisée, ZRV de type bassin) permettrait d'éliminer partiellement certains micropolluants par photodégradation (diclofénac, kétoprofène, etc.). L'objectif général de ce travail de doctorat était d'améliorer la compréhension des processus d'élimination des micropolluants organiques quantifiés en sortie de traitement secondaire par deux procédés de traitement complémentaire prometteurs : la photodégradation dans une ZRV de type bassin et l'oxydation à l'ozone mis en oeuvre par une tour d'ozonation sur une STEU réelle. Nous avons développé une méthodologie commune qui a été appliquée à l'étude de ces deux processus pour une sélection de 63 micropolluants réfractaires au traitement secondaire. La première étape a consisté à réaliser un état de l'art sur les études cinétiques disponibles dans la littérature. Deux bases de données ont ainsi été créées pour documenter les constantes cinétiques et rendements d'élimination pour 12 micropolluants. Ce travail a permis d'avoir une vision critique sur ces données issues de la littérature, notamment en ce qui concerne le réalisme des expérimentations vis-à-vis du traitement complémentaire d'eaux usées traitées. Lors de la deuxième étape, des études à l'échelle pilote ont été menées afin d'améliorer les connaissances sur les mécanismes d'élimination par oxydation par voie directe (photons ou O3) ou bien par voie indirecte (OH●). Ainsi, la voie de dégradation majeure (directe ou indirecte) a été déterminée pour les micropolluants étudiés. L'influence de certains paramètres physico-chimiques de l'effluent (nitrates, nitrites, MES, MOD) a également été abordée. Deux modèles numériques permettant de simuler l'élimination des micropolluants par photodégradation ou oxydation à l'ozone, respectivement, ont été développés et calés à partir des résultats obtenus. Dans la troisième étape, nous avons évalué les performances d'élimination des micropolluants à l'échelle des procédés de traitement complémentaire. Les constantes cinétiques mesurées expérimentalement ont permis de classer en 3 groupe (rapide, intermédiaire et lent) 47 micropolluants selon leur cinétique de dégradation par oxydation à l'ozone et, d'autre part, 42 micropolluants selon leur cinétique de photodégradation. Enfin des prévisions effectuées avec les deux modèles ont été comparées avec les mesures sur site. Ces résultats ont confirmé leur utilisation possible comme outil d'aide à la prédiction du comportement des micropolluants en traitement complémentaire<br>In the context of the implementation of the Water Framework Directive, the list of "priority" substances has been revised and a new list called "vigilance" was recently proposed for substances whose knowledge on exposure and dangerousness need to be document. However, current domestic wastewater treatment plants(WWTP), mostly secondary biological processes, were not designed to eliminate micropollutants. If WWTP eliminate the most part, many organic micropollutants (pesticides, pharmaceuticals, hormones, etc.) are still present in the treated water. Some tertiary treatment processes (or complementary) intensive or extensive recently been studied to determine their ability to remove micropollutants considered refractory to biological treatment (low biodegradable or low sorption on total suspended solids (TSS)) and / or present strong concentrations in raw water. Thus, oxidation by ozone or hydrogen peroxide, and the activated carbon adsorption have removal efficiencies higher than 70% for the majority of pesticides and pharmaceuticals. On extensive processes, recent studies suggest that solar radiation penetrating the water column (eg. soil-based constructed wetlands with basin) would partially eliminate some micropollutant with significant photodegradability (diclofenac, ketoprofen, etc.). The general objective of this PhD was to improve the understanding of the removal process of organic micropollutants quantified at the output of secondary treatment by two promising complementary treatment processes: photodegradation in a basin of soil based constructed wetlands and oxidation by ozone implemented by an ozonation tower on real WWTP. We have developed a common methodology that has been applied to the study of these processes for a selection of 63 micropollutants refractory to secondary treatment. The first step was to achieve a state of the art on kinetic studies in the literature. Two databases were created to document the kinetic constants and removal efficiencies for 12 micropollutants. This work allowed to have a critical view on the data from the literature, especially regarding the realism of the experiments for complementary treatment of treated wastewater. In the second step, studies on pilot scale have been carried out to improve knowledge about the oxidative removal mechanisms by direct (O3 or photons) or indirect pathway (OH●). Thus, the major contribution of degradation (direct or indirect) was determined for all micropollutants studied and the influence of specific physicochemical parameters of the effluent (nitrates, nitrites, TSS, DOM, etc.) was discussed. Two numerical models for simulating the removal of micropollutants by photodegradation or ozone oxidation have been developed and calibrated from the results. In the third step, we evaluated the removal performance of the micropolluants in the complementary treatment processes. The experimentally measured kinetic constants were used to classify in 3 groups (fast, medium and low) 47 micropollutants according to their kinetics of degradation by oxidation with ozone and, secondly, 42 micropolluants according to their photodegradation kinetics. Finally, predictions made with both models and were compared with measurements in real scale. These results confirmed their possible use as a tool to help to predict the behavior of complementary micropolluants treatment
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Koumeir, Diala. "Élimination des oestrogènes par Ozonation et Photocatalyse : cas de l’éthinylestradiol." Thesis, Lyon 1, 2009. http://www.theses.fr/2009LYO10285.
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Actuellement, les systèmes d’épuration des eaux n’ont pas été conçus pour éliminer les substances médicamenteuses notamment les hormones (estrogènes). Ces molécules sont ainsi déversées dans le milieu naturel et contaminent les rivières. Le 17 α-éthinylestradiol a été choisie comme molécule modèle pour illustrer la présence d’un perturbateur endocrinien dans une eau résiduaire. Cette molécule présente un réel risque pour la faune et la flore (Féminisation des poissons mâles, diminution de la reproduction…). L’objectif de ce travail est d’évaluer l’efficacité de la photocatalyse et de l’ozonation pour éliminer l’Ethinylestradiol dans les eaux. Le procédé d’oxydation utilisant l’ozone a été appliqué dans un premier temps sur des solutions concentrées d’éthinylestradiol (EE2 = 10 mg/L) préparées dans une eau ultrapure tamponnée afin de mieux comprendre les mécanismes d’élimination de ce composé et d’évaluer l’efficacité en terme de taux de conversion de EE2 et de la minéralisation du substrat. Les expériences réalisées ont permis de montrer que l’ozone est un oxydant très efficace pour oxyder l’éthinylestradiol. L’oxydation se fait essentiellement par réaction directe de l’ozone sur la molécule d’EE2 alors que sa minéralisation nécessite la conversion de l’ozone en radicaux hydroxyles qui vont ensuite réagir sur la structure saturée de la molécule organique. L’étude de l’ozonation de solutions EE2 à différentes concentrations a permis d’établir une relation entre la concentration initiale en polluant dans l’eau et la dose d’ozone à introduire pour éliminer ce composé à un pH proche de la neutralité. Cette relation a été utilisée pour estimer la dose d’ozone à appliquer pour une eau contaminée par EE2 à une concentration proche de celle rencontrée dans les eaux résiduaires et comparée à celle obtenue sur une eau provenant de la station d’épuration du Bourget du Lac. L’efficacité du procédé photocatalytique a été évaluée en travaillant sur les vitesses de disparition et de minéralisation de EE2 en présence de TiO2 «Degussa P25» et TiO2 PC500. Les cinétiques d’adsorption et de dégradation photocatalytiques ont été évaluées dans une gamme de concentration allant de 1 à 10 mg/L en travaillant à différentes masses de photocatalyseur. Les constantes d’adsorption et de vitesse, modélisés avec les modèles de Langmuir et Langmuir-Hinshelwood respectivement révèlent, (1) des propriétés d’adsorption et de photocatalyse plus importante pour le photocatalyseur TiO2 «Degussa P25», (2) des constantes d’adsorption différentes en présence ou en absence d’irradiation et aucune proportionnalité entre quantité de EE2 adsorbée et concentration en photocatalyseur. Cette absence de corrélation est expliquée en considérant la taille des particules. La formation d’agrégats de plus en plus important est observée en augmentant la masse de TiO2. La minéralisation de EE2 est totale après moins d’une heure d’irradiation en travaillant avec une puissance lumineuse de 5,5 mW/cm2 et 10 mg/L de EE2 indiquant l’efficacité de ce procédé<br>Currently, systems for water treatment have not been designed to eliminate drug substances such as hormones (estrogen). These molecules are thus discharged into the environment and contaminate rivers. The 17 α-ethinylestradiol has been chosen as model molecule to illustrate the presence of an endocrine disrupter in water waste. This molecule presents a real risk to wildlife (feminization of male fish, reduced reproduction ...). The objective of this work is to evaluate the effectiveness of photocatalysis and ozonation to remove Ethinylestradiol waters. The oxidation process using ozone was applied initially in concentrated solutions of ethinylestradiol (EE2 = 10 mg / L) prepared in ultrapure water buffered to better understand the mechanisms of elimination of this compound and evaluate the effectiveness in terms of conversion rate of EE2 and mineralization of the substrate. Experiments have shown that ozone is a very effective oxidant for oxidation of ethinylestradiol. Oxidation occurs mainly by direct reaction of ozone on the molecule while EE2 mineralization involves the conversion of ozone into hydroxyl radicals which will then react on the structure of the saturated organic molecule. The study of ozonation of EE2 solutions at different concentrations has established a relationship between the initial concentration of pollutant in the water and the dose of ozone introduced to eliminate this compound at a pH near neutrality. This relationship was used to estimate the dose of ozone applied to water contaminated with EE2 at a concentration close to that found in wastewater and compared to that obtained water from the treatment plant Bourget du Lac. In the second part of our work, we studied the advanced oxidation process "Photocatalysis". The adsorption and photodegradation of EE2 were performed on the surface of TiO2 Degussa P25 "and under UV radiation (λ = 365 nm). The results were modeled using the model of Langmuir and Langmuir Hinshelwood respectively. These models allowed us to determine for different masses of TiO2 quantities of EE2 adsorbed on the surface of TiO2 and the constants of adsorption in the dark under UV light, and the rate constants. These values were compared to those obtained under the same conditions but on a different type of catalyst TiO2 PC500. The measurement of particle size of TiO2 shows the formation of agglomerates increasingly important function of the mass of catalyst TiO2 PC500 and it allowed us to explain the values of the constants of adsorption and kinetic results
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Khatib, Fayez El. "Nouveaux modèles d'ozonides phosphorés générateurs d'oxygène singulet." Toulouse 3, 1986. http://www.theses.fr/1986TOU30002.
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Apres une mise au point detaillee sur l'ozone et l'oxygene singulet presentee dans le premier chapitre, l'addition oxydante de l'ozone sur le doublet libre des phosphites est etudiee. En faisant varier l'environnement autour de l'atome de phosphore, cette reaction conduit a la formation d'adduits ozonides penta ou hexacoordines. La troisieme chapitre, comporte l'etude de stabilite de ces nouveaux modeles d'ozonides. Ceux-ci se decomposent en generant de l'oxygene singulet. Dans le quatrieme chapitre, le rendement en oxygene singulet est determine, permettant de proposer un mecanisme reactionnel. A la recherche de nouveaux modeles d'ozonides, nous avons etudie la reaction de l'ozone sur des modeles moleculaires comportant la liaison phosphore-azote. Ces molecules fixent de diverses manieres de grandes quantites d'ozone pour conduire a des oligomeres peroxydiques
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Marcq, Olivier. "Ozonation du D-glucose et du beta-cellobiose marqués au carbone 13 : contribution à l'étude du processus d'oxydation des polysaccharides par l'ozone." Dijon, 2000. http://www.theses.fr/2000DIJOS025.
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Ce mémoire apporte une contribution à l'étude du processus d'oxydation des polysaccharides par l'ozone. Ce travail comporte étude bibliographique relative à la réaction de l'ozone avec le glucose et les composés modèles de cellulose, et, aux facteurs influençant la réaction de l'ozone sur la cellulose lors du blanchiment des pâtes à papier. L'ozonation de molécules de glucose marquées au carbone 13 a permis de déterminer l'origine du dioxyde de carbone formé. Le rôle primordial des positions C1 et C6 a été démontré. Un schéma réactionnel de l'oxydation de la fonction alcool primaire a été établi et comporte une étape d'oxydation et une étape de décarboxylation. L'influence du ph sur l'ozonation du glucose a été étudiée. Un schéma réactionnel global explicitant la formation de sous-produits comportant 1 à 6 atomes de carbone a été proposé. Lors de l'ozonation du cellobiose et l'alpha-cyclodextrine, une réactivité en position C6 a étée mise en évidence. Grace à l'ozonation cellobiose-1-13c, les voies de rupture de la liaison glycosidique à ph acide et l'oxydation de l'extrémité réductrice en milieu acide acetique ont pu etre confirmees par une analyse isotopique. La formation d'acide d-glucopyranosyl-beta-d-glucopyranuronique a ete demontree. Une selectivite notable de l'oxydation en position c6 a ete observee pour l'alpha-cyclodextrine. La reactivite de l'acide polygalacturonique modele des acides pectiques, des acides alginiques et de la cellulose oxydee en position c6 a ete etudiee. La reaction de decarboxylation des fonctions uroniques presentes dans une structure polymerique s'avere tres aisee. L'identification dans le milieu reactionnel d'acide arabinarique deja rencontre lors de l'ozonation du glucose et du cellobiose a permis de proposer un schema reactionnel d'ozonation de l'acide polygalacturonique et de l'oxydation des fonctions acide uronique. L'extremite reductrice des oses est la position la plus reactive vis-a-vis de l'ozone. La reactivite de la position c6 est cependant importante, et joue tres probablement un role essentiel dans le processus d'oxydation des polysaccharides. La formation de dioxyde de carbone observee industriellement est un parametre essentiel de l'ozonation des sucres. L'effet protecteur de l'acide acetique a ete confirme et un effet similaire de l'acide phosphorique a ete demontre.
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Shin, Won-Tae. "Effects of electric fields on fluids : applications in ozonation." Diss., Georgia Institute of Technology, 2000. http://hdl.handle.net/1853/32770.
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Votruba, Michael Julian. "Ozonation of Tris-2-Chloroethyl Phosphate (TCEP) in Water." Digital WPI, 2013. https://digitalcommons.wpi.edu/etd-theses/860.
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"Tris-2-chlorethyl phosphate (TCEP) is a flame retardant and plasticizer that has been detected in drinking water sources and wastewater effluents in many countries. TCEP has been proven to be a recalcitrant compound that is also toxic and carcinogenic. The incomplete removal of TCEP in water and wastewater treatment plants necessitates that treatment processes be identified or developed that will completely remove TCEP from waters. Ozonation has been successfully used as an oxidant to degrade many problematic contaminants in water and wastewater. This research examined the effectiveness of ozone and ozone/hydrogen peroxide oxidation for removing TCEP from water. In laboratory experiments, batch reactions of TCEP solutions were conducted in purified water at different pH conditions and O3:H2O2:TCEP doses. The samples were tested at O3:TCEP molar ratios of 6:1, 15:1, and 30:1 and with O3:H2O2:TCEP molar ratios of 6:4.2:1, 15:10.5:1and to 30:21:1 respectively. Solution pHs of 4, 7, and 9 were investigated to cover the typical water and wastewater pH range. The Indigo Method was used to measure the starting ozone concentrations in sample water. TCEP concentrations were quantified by liquid-liquid extraction followed by gas chromatography (GC). Greater than 90% reduction of TCEP was achieved at equilibrium conditions with an O3:H2O2:TCEP molar ratio of 30:21:1 at all pH levels examined. Greater than 80% TCEP removal in diluted wastewater was observed at purified water to wastewater dilution of 4:1. The kinetics of oxidation of TCEP with ozone and ozone/hydrogen peroxide were explored in this research. It was found that the reaction rate constants of TCEP are lower than those of other contaminants typically found in water and wastewater. "
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Paillard, Hervé. "Etude de la minéralisation de la matière organique dissoute en milieu aqueux dilué par ozonation, oxydation avancée O3/H2O2 et ozonation catalytique hétérogène." Poitiers, 1994. http://www.theses.fr/1994POIT2357.
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On assiste, depuis plusieurs annees, a une augmentation sensible de la concentration en carbone organique dans les eaux a potabiliser. Cette matrice organique presente une fraction soluble importante, mal retenue par les filieres de traitement classiques. Pour combattre les problemes de qualite d'eau lies a un exces de composes organiques dissous (micropollants, thm, tox, codb), nous avons cherche a mettre au point, dans cette etude, un procede d'oxydation totale du carbone organique utilisant l'ozone. Il est montre, avec plusieurs types d'eaux (eau pure avec molecules modeles, eau reconstituee avec substances humiques et eaux naturelles), qu'un degre d'oxydation pousse peut etre atteint sur des molecules organiques refractaires a une ozonation simple par la mise en uvre d'une oxydation radicalaire avec le systeme o#3/h#2o#2. Le mecanisme d'oxydation radicalaire de l'atrazine est particulierement etudie, aussi bien en eau pure qu'en eau naturelle. Les sous produits d'oxydation sont assez differents mais on retrouve, dans les deux cas, la desethyl-atrazine et la deisopropyl-atrazine comme sous-produits majoritaires. Les conditions optimales d'application du systeme o#3/h#2o#2 sont les memes quelles que soient la nature des molecules organiques a oxyder, c'est a dire: un ph voisin de 7,5 (entre 7,5 et 8,0). Un ratio h#2o#2 injecte/o#3 injecte de 0,5 mole par mole. Les pieges a radicaux, l'alcalinite en particulier, ainsi que la nature de la matrice organique n'influent pas sur ces conditions optimales d'application mais entrainent une reduction importante de la vitesse et du rendement d'oxydation. Un modele predictif d'oxydation des micropolluants en eau naturelle, etabli a partir des donnees de la bibliographie et des resultats experimentaux, a permis de simuler avec une bonne precision l'effet des parametres les plus importants (doses d'o#3 et d'h#2o#2, ph, alcalinite, cot, temperature, type de micropolluant et sa concentration) du traitement d'oxydation par l'ozone seul ou par le systeme o#3/h#2o#2. En eau naturelle, l'oxydation du cot et de la plupart des micropolluants reste incomplete. Il est possible d'accroitre le pouvoir d'oxydation de l'ozone et de l'oxydation avancee o#3/h#2o#2 par la mise en uvre, dans le milieu reactionnel, d'un catalyseur solide a base d'un oxyde mixte de ti-cu (appele gat) depose sur support alumine. Ce catalyseur semble limiter l'effet de piege a radicaux de l'alcalinite et du cot. L'ozonation catalytique o#3/gat est un systeme oxydant presentant une selectivite importante vis a vis du codb et des molecules organiques a fonctions carboxyliques et aldehydes-cetones dans une moindre mesure. L'injection de h#2o#2 pendant l'ozonation catalytique rend ce systeme moins selectif. Ainsi, la combinaison o#3/h#2o#2/gat permet d'oxyder des pesticides organo-chlores du type lindane, hch et endosulfan en eau naturelle a un degre beaucoup plus eleve que celui obtenu avec le systeme o#3/h#2o#2
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Pages, Marielle. "Effets et mécanismes d'action de l'ozone utilisé comme moyen de lutte contre des champignons pathogènes du pommier : études in vitro et in vivo." Thesis, Toulouse, INPT, 2015. http://www.theses.fr/2015INPT0102.
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Les pommiers sont la cible de nombreux ravageurs et maladies fongiques, à l’origine de pertes économiques importantes. Les agriculteurs sont dans l’obligation de traiter les micro-organismes responsables des maladies fongiques, notamment à l’aide de pesticides. Les produits phytosanitaires sont aujourd’hui très controversés. Ainsi, les pouvoirs publics, français et européens, contrôlent leur emploi par de nombreuses règlementations. Par conséquent, il apparaît nécessaire de proposer une alternative peu rémanente permettant de contrôler le développement fongique. L’objectif de cette thèse est d’évaluer l’efficacité d’une alternative innovante basée sur l’emploi d’eau chargée en ozone contre quatre espèces fongiques à l’origine des principales maladies du pommier : Venturia inaequalis, Botrytis cinerea, Neofabraea alba et Phytophthora syringae. Dans un premier temps, ce travail de thèse a permis de vérifier l’action anti-fongique de l’ozone sur les suspensions de spores des quatre espèces fongiques ainsi que sur différents stades de développement des spores de V.inaequalis. Il a été mis en évidence une différence de sensibilité selon l’espèce et le stade de développement considérés. Par ailleurs, l’altération de la membrane sous l’action de l’ozone a été observée par plusieurs expérimentations : quantification du degré de peroxydation des phospholipides membranaires, observations des spores au Microscope Electronique à Balayage et au Microscope Optique après colorations. Dans un second temps, l’effet de l’eau chargée en ozone a été évalué sur des jeunes plants de pommiers préalablement contaminés par les spores de V.inaequalis. Cette étude a confirmé l’action anti-fongique de l’eau chargée en ozone. Il a également été observé l’importance des quantités d’eau et d’ozone apportées qui doivent être maîtrisées pour optimiser l’efficacité du traitement. Ces résultats permettent de valider la candidature de l’ozone comme fongicide alternatif à l’emploi de produits phytosanitaires. Les modalités d’application devront faire l’objet de recherches supplémentaires en vue du transfert de la technologie du laboratoire au verger<br>Apple trees are the target of a lot of pests and fungal diseases, responsible for many economic losses. Farmers treat these micro-organisms mainly with pesticides. Plant-protection products are today very controversial. French and European authorities control their use by means of numerous regulations. Therefore, an alternative solution with a low remanence must be found in order to limit fungal diseases. The aim of this thesis is to evaluate the innovative process efficiency based on the use of ozonated water against four fungal species: Venturia inaequalis, Botrytis cinerea, Neofabraea alba and Phytophthora syringae. Firstly, this work of thesis verified the ozone antifungal action on spores suspensions of the four fungal species and on different stages of development of V.inaequalis spores. According to the species and stages of development considered, a difference of sensibility was detected. Moreover, alteration of the membrane, due to ozone action, was observed thanks to several experimentations: quantification of phospholipids peroxidation, spore observations with Scanning Electron Microscopy and with Optical Microscopy after staining. Secondly, the ozonated water effects on seedlings previously contaminated by V.inaequalis spores were evaluated. This study confirmed the anti-fungal action of water containing ozone. It was also observed the importance of the water and of ozone quantities supplied. These quantities must be controlled to optimize the antifungal action of the treatment. These results validated the ozone application as a fungicide alternative of use of pesticides. Additional researches will be made concerning the treatment modalities: the aim is to transfer the technology from the laboratory to the orchard
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Stockinger, Hermann. "Removal of biorefractory pollutants in wastewater by combined ozonation-biotreatment /." [S.l.] : [s.n.], 1995. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=11063.
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Marda, Saurabh. "Effect of Ozonation and BAC Filtration Processes on Monochloramine Demand." Thesis, Georgia Institute of Technology, 2005. http://hdl.handle.net/1853/10577.
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Although the kinetics and mechanism of monochloramine decay in organic-free waters are relatively well understood, those in natural waters are not, due to exceedingly complex and poorly defined interactions of monochloramine with natural organic matter (NOM) and particles. Ozonation followed by a biologically activated carbon (BAC) filtration is a commonly practiced process option that affects the characteristics of both dissolved and particulate constituents in the water. However, how these changes in water constituents affect stability of the residual disinfectant, or monochloramine in particular, are currently unknown. Kinetics of monochloramine decay in water samples obtained before and after ozonation and BAC treatments were performed under varying operating conditions were determined by bench-scale batch experiments. Stability of monochloramine in the BAC filter effluent samples obtained at different times after backwashing was determined. It was found that in most cases monochloramine stability was greatly decreased after BAC filtration. Further filtering the BAC effluents with 1.2 and #61549;m polycarbonate membrane resulted in a substantial increase in monochloramine stability. A further increase was observed after filtering the samples using a 0.4 m membrane. This finding suggested that particulate matter generated from the filters could be the major cause of monochloramine instability. The fines from the activated carbon, possible components of the particulate matter eluting from the BAC filters, were found to exert an insignificant monochloramine demand both in the presence and absence of NOM, which is contrary to previous speculation in the literature about their demand for monochloramine. While there appears to exist a relationship between chloramine demand and HPC count of the filter effluent, more research will be needed to determine the effect of nature and type of microorganisms and their byproducts have on chloramine demand. Effect of ozonation on monochloramine stability is also under investigation using both the water sampled from full-scale plant and the synthetic water prepared with Suwannee River NOM.
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Pirgalioglu, Saltuk. "Catalytic Ozonation Of Dye Solutions In A Semi-batch Reactor." Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/3/12610158/index.pdf.
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Treatment of textile wastewaters containing dye materials using the conventional methods based on biological treatment is not possible. In order to overcome this problem, ozonation based on the oxidation of organic pollutants with ozone gas dissolved in aqueous phase have been studied widely. Catalytic ozonation and advanced oxidation processes (AOP) are also used in order to increase the efficiency of sole ozonation
In this work, catalytic ozonation processes in the presence of Copper Sulfide (CuS) powder and a synthesized catalyst by the impregnation of iron on alumina (Fe/Al2O3) were studied separately in the treatment of dye solutions, namely Remazol Brilliant Blue-R (RBBR) and Reactive Black-5 (RB-5). Besides catalytic ozonation runs, ozonation parameters and ozonation mechanism were also studied and a model was developed for the semi-batch ozonation.
Both catalysts increased the oxidation of side products measured by the decrease in the amount of total organic carbon (TOC) in the treated dye solutions. Dye removal rates were also enhanced in the treatment of RB-5 dye solutions while no significant effect was observed on dye removal rates of RBBR solutions.
TOC removals above 90% were observed in the catalytic ozonation using CuS for both of the dye solutions at pH =10 having initial dye concentration of 100 mg/L. The most significant effect of the catalyst addition was observed at pH = 3 where the TOC removals of non-catalytic ozonation were the lowest. CuS addition increased percent TOC removal at the end of the reaction period of 80 min by 123% in the treatment of 100 mg/L RBBR solution, and by 65% in the treatment of 100 mg/L RB-5 solution at pH = 3. On the other hand, addition of Fe/Al2O3 catalyst increased TOC removal of 100 mg/L RB-5 solution by 52 % at pH = 3.
In addition, volumetric mass transfer coefficients (kLa) of ozone in the absence and in the presence of a chemical reaction between dye and ozone were estimated from modeling. A correlation for the enhancement factor of ozone absorbed into dye solutions in terms of initial dye concentration was obtained and reported.
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Abouzlam, Manhal. "Optimisation d'un procédé de traitement des eaux par ozonation catalytique." Thesis, Poitiers, 2014. http://www.theses.fr/2014POIT2251/document.
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Le principal objectif de la thèse est l'optimisation d'un procédé d'oxydation avancée par la mise en œuvre des outils de l'automatique moderne.Le procédé considéré concerne l'ozonation catalytique utilisé pour traiter les eaux résiduaires industrielles. L'optimisation de ce procédé consiste à contrôler l'abattement des polluants tout en minimisant le coût de fonctionnement du procédé. La mesure en ligne de la concentration en polluant est fournie par l'absorbance, grandeur corrélée à la DCO. Le procédé est alors considéré comme un système à une entrée, la puissance du générateur d'ozone, et deux sorties, l'ozone dans les évents et l'absorbance.L'identification du procédé a mené à l'estimation d'un modèle linéaire pour construire les lois de commande et d'un modèle non-linéaire, de type modèle de Wiener, pour tester les correcteurs en simulation avant les essais expérimentaux.Les trois commandes testées, la commande par modèle interne, la commande optimale et la commande H∞, permettent de rejeter des perturbations sur la concentration en polluant dans les effluents à traiter. Des analyses de stabilité du système bouclé, vis-à-vis de retards sur la commande, ont été menées.Les résultats expérimentaux obtenus ont permis de conclure sur les gains significatifs apportés par ces développements.La méthodologie développée pour cette application peut être étendue à d'autres procédés afin de faciliter le développement industriel des procédés d'oxydation avancée<br>The main goal of the PhD thesis focuses on the optimization of an advanced oxidation process by implementing the modern control tools.The considered process is a lab-scale pilot of industrial wastewater treatment by catalytic ozonation. The optimization of this process is achieved by controlling the pollutant abatement while minimizing the high operating costs. The online measurement of the pollutant concentration is provided by the absorbance which is correlated with COD. Therefore, the process is considered as a system with one input, the ozone generator power, and two outputs, the ozone gas concentration at the top of the reactor and the absorbance.A linear model of the process was identified. It allowed calculating the control laws. And a nonlinear model, with a so-called Wiener model structure, was also identified to test the controllers in simulation before the experiments.The three control methods applied, the internal model control, the optimal control and the H∞ control, allow rejecting disturbance on the pollutant concentration of the effluent to be treated.The stability of closed-loop system with delayed control input was analyzed.The experimental results show the significant benefits provided by this closed-loop system.The methodology developed for this application can be extended to other processes to facilitate the industrial development of advanced oxidation processes
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Facile, Nathalie. "Mesure des CT d'inactivation des bactéries sporulantes aérobies par ozonation." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0001/MQ38678.pdf.
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Currie, Martin James. "Enhancement of particle removal in water treatment by pre-ozonation :." Thesis, Imperial College London, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.412314.
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Heng, Samuel. "Réacteur catalytique membranaire pour le traitement de l'eau par ozonation." Montpellier 2, 2006. http://www.theses.fr/2006MON20128.
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Un réacteur membranaire innovant comportant une double enveloppe a été conçu et testé pour le traitement de l'eau par ozonation. Le couplage d'une séparation membranaire avec l'ozonation dans un même réacteur a permis d'améliorer considérablement la dégradation du polluant organique modèle sélectionné, tout en évitant le colmatage de la membrane zéolithe. Parallèlement, une méthode originale a été mise au point pour éliminer, par ozonation, le template obstruant les pores des membranes zéolithes. Cette méthode permet l'obtention de membranes de qualité supérieure par rapport aux méthodes classiques. Par ailleurs, des catalyseurs reportés dans la littérature comme étant catalytiquement actifs pour l'ozonation ont été préparés et testés. Les résultats montrent que l'alumine gamma et les catalyseurs supportés de ce type ne sont pas vraiment des catalyseurs. L'amélioration de l'abattement du polluant serait due en majorité à l'adsorption des produits de dégradation par le support<br>A novel double membrane reactor was constructed and tested for continuous water and wastewater treatment by ozonation. The coupling of membrane separation and ozonation in the same reactor was found to significantly enhance the degradation of the selected model organic pollutant, while preventing fouling of the zeolite membrane. In parallel, an original ozonation method has been developed for removing the organic template from the zeolite membrane pores. This low temperature activation method results in higher quality membranes compared to traditional activation methods. Additionally, catalysts commonly reported in the literature to be active for ozonation were prepared and tested. The results demonstrated that gamma alumina and alumina supported catalysts do not have a real catalytic activity. The observed enhancement of organic removal during catalytic ozonation is mainly due to the contribution of adsorption and possibly to metal leaching from the catalyst
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Bui, Quang Minh. "Oxydation de molécules modèles en solution aqueuse par ozonation catalytique." Poitiers, 2009. http://www.theses.fr/2009POIT2267.
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L'objectif de ce travail a été d'examiner et de démontrer l'activité d'un catalyseur hétérogène lors de l'ozonation de solution aqueuse de quelques molécules modèles. Il devrait également permettre une meilleure connaissance des mécanismes impliqués dans ce système oxydant. Pour cela, une étude de l'oxydation par ozonation catalytique de quelques composés réfractaires (acide pyruvique, acétique, oxalique et oxamique) et de composés pharmaceutiques (iohexol, progestérone) a été menée. Dans une première partie, une augmentation de la dégradation et de la minéralisation des acides carboxyliques et de l'acide oxamique lors de l'ozonation catalytique a été observée. Les acides acétique et oxalique formés lors de l'oxydation de l’acide pyruvique sont les sous-produits majoritaires. La formation importante de l'ion ammonium par rapport à l'ion nitrate pour l'oxydation de l'acide oxamique montre une différence de mécanisme entre l'ozonation catalytique et l'oxydation par les radicaux hydroxyles ou l'ozone moléculaire. Dans une deuxième partie, consacrée à de plus faibles concentrations en composés a montré que l'iohexol et la progestérone peuvent être dégradés par ozonation. La présence de catalyseur accélère la réaction. Aucune de sous-produits n'a cependant été mise en évidence entre les deux systèmes oxydants. Les étapes du mécanisme comprendraient (1) l'interaction de l'ozone avec du catalyseur, (2) l'adsorption du composé sur le site actif formé, (3) l'oxydation du composé organique adsorbé, (4) la désorption des sous-produits. Le procédé d’ozonation catalytique peut donc l'oxydation de composés réfractaires mais aussi une voie de dégradation complémentaire pour les composés réactifs vis-à-vis de l'ozone ou des radicaux hydroxyles<br>The aim of this work is to examine and demonstrate the activity of a heterogeneous catalyst in the ozonation of an aqueous solution of some model molecules. The objective is also to better understand the mechanisms of this process. The oxidation of some refractory compounds (pyruvic acid, acetic, oxalic, and oxamic) and pharmaceutical compounds (iohexol, progesterone) by catalytic ozonation was carried out. In a first part, an enhancement of efficiency and mineralization of carboxylic acids and oxamic acid in catalytic ozonation was archived. The acetic acid and oxalic acid were formed the majority of by-products during the oxidation of pyruvic acid. Important formation of ammonium ion versus the nitrate ion for the oxidation of oxamic acid shows a difference between the mechanism of catalytic ozonation and oxidation by hydroxyl radical or ozone molecule. In the second part, for the pharmaceutical compounds studied (iohexol and progesterone), a degradation and identification of by-products of oxidation in catalytic ozonation versus ozonation was undertaken. Although the catalytic process unables the enhancement of the kinetic of oxidation, neither difference of by-products was observed which show the oxidation through free radicals. This effect of the catalyst promoted ozonation involves a process for degradation by the active species formed and hydroxyl radicals. The scheme of the reaction pathway was suggested that the mechanism consist of the steps: (1) the interaction of ozone with catalyst (2) adsorption of the compound on the active site formed, (3) oxidation of organic compound adsorbed, (4) desorption of the by-products
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Legay, Cécile. "Ozonation catalytique des polluants organiques pour le traitement de l'eau." Toulouse, INPT, 1998. http://www.theses.fr/1998INPT100G.
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Les travaux présentés dans ce mémoire concernent l'ozonation catalytique des composés organiques pour le traitement des eaux résiduaires industrielles. Parmi les traitements visant à réduire la pollution organique contenue dans les effluents, l'ozonation constitue un des moyens d'oxydation les plus efficaces. Cependant l'action sélective de l'ozone conduit généralement à un abattement limité du COT, ce qui motive le développement de procédés d'oxydation avancée, susceptibles de conduire à la minéralisation complète de la matière organique. Une investigation expérimentale permet initialement d'établir l'ordre d'efficacité des métaux de transition dans la décomposition de l'ozone, hors substrat, et de préciser le rôle du métal dans l'activation catalytique de l'ozone. L'hétérogénéisation du catalyseur par imprégnation en voie humide permet ensuite de combiner l'activité obtenue en phase homogène et la séparation aisée catlyseur/produit propre à la catalyse hétérogène. Après avoir sélectionné l'agent actif, l'optimisation de la formulation catalytique est réalisée d'après les performances obtenues vis-à-vis de la dégradation de divers substrats modèles, inertes vis-àvis de l'ozone. Les performances de l'ozonation catalytique sont ensuite validées par l'application au traitement d'effluents industriels. L'activation catalytique de l'ozone repose en effet sur la formation d'entités oxydantes non radicalaires et se distingue par là même de tous les procédés d'oxydation avancée existants à l'heure actuelle. Toutes ces validations expérimentales prouvent le bien fondé de la démarche adoptée. Enfin, ce travail ouvre des perspectives orientées vers le développement du procédé industriel.
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Orlandini, Ervin. "Pesticide removal by combined ozonation and granular activated carbon filtration /." Rotterdam ; Brookfield : Balkema, 1999. http://catalogue.bnf.fr/ark:/12148/cb37738501t.
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Mamouni, Abderrahim. "Photolyse directe et indirecte du carbétamide seul et formulé." Lyon 1, 1989. http://www.theses.fr/1989LYO10191.
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L'etude photochimique du carbetamide seul et formule nous a permis de mettre en evidence l'importance de la photolyse indirecte dans sa degradation. Tous les parametres spectroscopiques du carbetamide et des surfactants ont ete determines, en vue d'etudier les effets d'ecran ou de transfert d'energie entre molecules. Par des experiences de cinetique, nous avons pu preciser le role des adjuvants de formulation, ainsi que le mecanisme de photodegradation. Par les techniques d'analyses rmn, chromatographie et spectrometrie de masse, ainsi que les sites reactionnels de la molecule. Une etude complementaire, en presence d'ultraviolet, entre l'ozone, le dioxyde de titane et le peroxyde d'hydrogene, a confirme le role du radical oh#. Dans la photolyse. Dans ces dernieres conditions, nous obtenons non seulement la degradation de la chaine aliphatique, mais egalement l'ouverture du cycle aromatique
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Bouland, Sandrine. "Etude et suivi des ions bromate au cours du traitement de potabilisation de l'eau." Paris 11, 2004. http://www.theses.fr/2004PA112181.
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Cette étude a pour objet d'évaluer l'impact du traitement de potabilisation dans les conditions d'exploitation habituelles, , sur les teneurs en bromate et en bromure (précurseur des ions bromate) dans trois usines de production d'eau potable de la région parisienne. Une méthode analytique par chromatographie ionique couplée à un détecteur conductimétrique a été développée. La limite de quantification est de 2 et 5 æg/L respectivement pour les ions bromate et bromure. Les résultats obtenus montrent que la préozonation ne contribue pas à la formation d'ions bromate. Les ions bromate sont formés au cours de la post-ozonation et sont introduits au cours de la chloration. Etant donné que les teneurs en bromate dans les eaux produites par ces trois usines excèdent parfois les limites de qualité fixées par la législation française, des essais ont été entrepris en usine de manière à minimiser la formation des ions bromate sans nuire à la désinfection. L'ensemble des essais montrent la difficulté, voire l'impossibilité de respecter les critères de potabilité vis-à-vis du paramètre bromate. La dernière partie de l'étude est consacrée à l'évaluation de l'impact éventuelle d'acides aminés (la glycine, l'acide aspartique, l'acide glutamique et l'isoleucine) sur la formation des ions bromate. Les premiers résultats montrent que l'impact des acides aminés sur la formation des ions bromate semble dépendre du rapport molaire acide aminé/bromure, du pH et de l'acide aminé<br>The object of this study is to evaluate the impact of drinking water treatment under usual exploitation conditions, on bromate and bromide concentrations in three waterworks upstream Paris. An analytical method based on ionic chromatography coupled with a conductivity detector was developed. The quantification limit of bromate and bromide is 2 and 5 æg/L respectively. The results obtained show that preozonation doesn't play a role in bromate formation. Bromate ions are formed during post-ozonation and are introduced during the chlorination step. Bromate concentrations encountered in drinking water produced by these three waterworks exceed the quality parameters fixed by French regulation, especially in summer. Studies were therefore realised in the plants to minimize bromate formation. The results show the difficulty or even the impossibility to reach the objective. The last part of the study is dedicated to the impact of amino acids (glycine, aspartic acid, glutamic acid and isoleucine) on bromate formation. The first results show that the impact of amino acid seems to depend on amino acid/bromide molar ratio, pH and on the nature of the amino acid
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Clapp, Benjamin R. "Ozonation of Lake Mendota water." 2001. http://catalog.hathitrust.org/api/volumes/oclc/46429168.html.
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Thesis (M.S.)--University of Wisconsin--Madison, 2001.<br>Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 94-97).
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Tsai, Yi-Ying, and 蔡宜穎. "The Investigation of ORP and Free Radical Mechanisms on Ozonation and Ozonation combined with Ultrasonic Processes." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/81336506076484412113.
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碩士<br>東海大學<br>環境科學與工程學系<br>97<br>This study collected natural water samples from Te-Chi Reservoir which provides major drinking water in the metropolitan central Taiwan. The water sample organic contents were extracted and classified into humic acids (HAs, 47.4%), fulvic acids (FAs, 4.7%), hydrophobic neutrals (42.2%), hydrophobic bases (0.7%) and hydrophilic fractions (5.0%) by DAX-8 resins. When raw water is disinfected by chlorination and some species of natural organic matters (NOMs), e.g. humic acids and their related substances are easily to form carcinogenic or mutagenic by-products cause the damage to human health.
The Te-Chi Reservoir raw water was ozonated and ozonated combining with ultrasonic process to investigate the oxidation reaction mechanisms. This study established the free radical measurement technique to the water system by the reduction of the combination coumarin with free radical. A design of experiments (DOE) method was adapted to obtain the optimal conditions for the AOP processes. The on-line data of oxidation reduction potential (ORP), dissolved ozone (DO3) and pH were collected by an oscilloscope to investigate the ozonation and ozontion combined with ultrasonic mechanisms. The ozone direct reaction and • OH redicals indirect reaction contributed 28.5% and 71.5%, in all ozonation process respectively. The change of functional groups during ozonation and ozonation combined with ultrasonic were examined by using 13C NMR (13C nuclear magnetic resonance) and FTIR (Fourier-Transform infrared spectrophotometer) spectra. The variation of functional groups can represent the destruction by ozonation and and Ozonation combined with ultrasonic in this study.
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Hartmann, Caroline M. "Identification and fate of mixed ozonation/chlorination and ozonation/chloramination by-products in drinking water treatment." 2002. https://scholarworks.umass.edu/dissertations/AAI3056236.
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Disinfection may cause a dilemma for drinking water treatment plants using chlorine for the maintenance of a disinfectant residual in distribution systems. On one hand the chlorine residual should ensure microbially safe drinking water, but on the other hand harmful disinfection by-products (DBPs) can be formed from the reaction of natural organic matter (NOM) with chlorine. Many utilities are looking to the combined use of ozonation for primary disinfection, followed by chlorine or chloramines as a means of minimizing DBP formation while maintaining a stable disinfectant residual. However, these combinations may lead to a new spectrum of by-products that differs from that produced when a single disinfectant is used. The formation of mixed ozonation/chlorination and ozonation/chloramination by-products is the subject of this dissertation. A diverse collection of precursor compounds that produce a large amount of “unknown” total organic halides (TOX) was identified by performing bench scale tests to simulate chlorination of known ozonation by-products. Simple mono- and di-carboxylic acids were not found to react with chlorine. Di-aldehydes, α-keto-acids, and α-hydroxy-acids are oxidized by chlorine but do not show TOX formation. However, chlorine does become incorporated in β-diketones. Oxalacetic acid, 3-methyl-2,4-pentanedione, acetonedicarboxylic acid, and malic acid were found to form more “unknown TOX” than common chlorination by-products. Usually, the chlorine demand as well as the TOX increase with decreasing pH and increasing chlorination time. The identification of “unknown TOX” was the second major goal of this work. Quenched samples from the model compound studies were derivatized with pentafluorobenzylhydroxylamine (PFBHA), extracted with methyl-tert-butyl-ether (MtBE), and silylated with bis-(trimethylsilyl)-triflouroacetamine (BSTFA). Malic and acetonedicarboxylic acids were each found to produce a previously-unknown byproduct after reacting with chlorine. The identity of this and other new by-products was suggested based on the mass spectra. Surprisingly, mono-chlorinated species were found to be more abundant than di-chlorinated species in all cases. The third phase of this research showed that a substantial amount of “unknown TOX” is also formed in distribution systems where chlorine is used as final disinfectant. The “unknown TOX” ranged between 60% and 80% of the measured TOX.
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吳仲平. "Ozonation of 2,4-diaminotoluene in water." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/27056788913287608865.
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碩士<br>國立臺灣大學<br>環境工程學研究所<br>90<br>The oxidation of 2,4-diaminotoluene in water with ozone and combined with hydrogen peroxide and UV radiation has been studied.
By using the fractional factorial design, a kind of experiment designs, the influence of ozone dosage, pH, hydrogen peroxide concentration and UV radiation on the ozonation of 2,4-diaminotoluene was investigated.
The results show that under most conditions, 2,4-diaminotoluene could be eliminated by ozonation. However, the total organic carbon (TOC) removal is relatively low by single ozonation alone.
According to the analysis of variances (ANOVA) of experiment data, it appears that UV radiation is the most important factor in this study. That means the TOC removal is improved by UV/O3 system effectively. Ozone dosage is also an important factor. Higher ozone concentration can also enhance the TOC removal.
Except that in acidic condition, TOC removal rate is decreased, the effect of pH controlled by buffer solution is not evident. The use of H2O2 improves TOC removal but the effect is not obvious difference when the H2O2 concentration rises from 2.68×10-4M to 2.68×10-2M.
The most proper condition of ozonation of 2,4-diaminotoluene in this study is high ozone dose with low H2O2 concentration and with UV radiation in unbuffered solution.
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Peng, Tzuwen, and 彭子玟. "Treatment of membrane concentrate by ozonation." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/87908033535598109378.
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碩士<br>國立聯合大學<br>環境與安全衛生工程學系碩士班<br>101<br>Abstract
The feedwater of this study is collected from the RO concentrate of TFT-LCD effluent. The concentrate is treated after ozone oxidation, then imported to RO membrane processes to improve water quality and permeate flux, expected to increase the recycling of concentrate.
Study of the combination of ozonation and RO membrane was processed under below parameters: different feed water recovery (permeate volume / original feed water volume) of concentrated fed water and different concentrations of ozone. All test of RO film program were controlled under 60 psi (4 Kg/cm2) operating pressure and 25oC feed water temperature.
The research results show that ozonation can effectively reduce the feed water color and the permeate flux decay when the applied voltage was 65 V. The higher the voltage applied, the higher recovery rate was got. However, fouling caused by organic matter was increased, when increase the higher water recovery. It indicated that the concentrate would be less, and the solute stays within the membrane tube would be more, resulting in the more serious film blocking.
This study shows that the combination of ozonation and RO membrane can effectively improve the permeate water quality and reduce the degree of permeate flux decay. Therefore, appropriate dosing of ozone can increase the recovery rate of wastewater.
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Chen, Sheng-han, and 陳聖翰. "Oxalic Acid Degradation Using Heterogeneous Catalytic Ozonation." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/44823550253326304319.
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碩士<br>逢甲大學<br>環境工程與科學所<br>95<br>The degradation of oxalic acid using heterogeneous catalytic ozonation has been conducted in an agitated slurry semi-batch reactor, where ZnO, Iron oxyhydroxide, and rice husk ash（RHA）were used as catalysts, respectively. The addition of catalysts has been found to be able to quantitatively increase the formation of free radicals and to effectively enhance the decomposition of oxalic acid. In addition, the influence of different variables, such as pH, catalyst dosage, and inlet ozone gas concentration, on the removal of oxalic acid has been investigated under desired conditions.
It is found that only slight enhancement of oxalic acid degradation was noted in the presence of ZnO or iron oxyhydroxide with ozonation at different catalyst dosages. In contrast, the increase in RHA dosage from 0.05 g to 0.25 g would lead to a significant decomposition of oxalic acid from 27％ to 79％. However, the decomposition amount of oxalic acid would not be increased by the addition of more RHA up to 0.5 g, indicating 0.25 g RHA is the optimum dosage. The pH value in solution is also another influential factor for the removal of oxalic acid. The optimum reaction pH was substantially related with pHpzc of catalyst itself. When the reaction pH approximates to pHpzc of the catalyst, it would be beneficial for organics or ozone molecules to approach the active sites of catalyst surface and to form substances which are more reactive. Thus, the optimum pH for ZnO and iron oxyhydroxide is 10, but the optimum pH for RHA is 3. The removal rate of oxalic acid is enhanced with the increase of inlet ozone gas concentration in the presence of catalysts. If comparing the amount of oxalic acid removed per unit applied ozone dose, we find that RHA has the best catalyst activity and ZnO is the worst in the ozonation of oxalic acid. Based on the results from ozone decomposition experiment, the ozone decomposition efficiency by RHA was almost identical as that of iron oxyhydroxide. Since RHA has relatively large surface area than oxyhydroxide, the catalytic efficiency of RHA is better than iron oxyhydroxide. Besides, ZnO was also used to test its photocatalytic ability with UV in the research. It is found that ZnO has poor photocatalytic activity in oxalic acid degradation with UV/ZnO. The enhanced removal ability for oxalic acid in O3/UV/ZnO system can be attributed to the reaction between ozone and UV. When ZnO is used as a catalyst in this study, the releasing of zinc ion from ZnO solid into solution has been observed. It might be the reason for poor ZnO catalytic activity. The kinetics study of oxalic acid degradation in the presence of RHA was involved in this experiment. It shows that oxalic acid degradation follows a first-order reaction and the reaction rate is proportional to the total surface area of catalysts used.
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Hsu, Wei-Chun, and 徐偉峻. "Fouling Removal from Ultrafiltration Membrane by Ozonation." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/68094579372774984087.
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碩士<br>國立中央大學<br>環境工程研究所<br>93<br>The objectives of this study are aimed to investigate the degree and kind of membrane fouling formed from the ultrafiltration (UF) of the tertiary treatment water in an industrial park, and to evaluate the feasibility of removing membrane fouling by ozone. The material of membrane used in the experiments was polyvinylidene fluoride (PVDF), as it could resist the corrosion of ozone. In order to assess the degree and kind of membrane fouling, the first step was to investigate the water quality characteristic of the tertiary treatment water and then set up the basic characteristics of the membrane, such as the initial permeate flux, the membrane resistance, and the pore size of UF membrane. In order to offer the reference for the real factory operation, a bench-scale membrane system was performed in the experiments to evaluate the fouling removed by three kinds of different ozonation, such as influent preozonation, ozone in-line dosing and ozone backwashing.
Experimental results showed that the removal efficiency of iron, manganese and SDI was 62%, 30% and 88%, respectively, after the 5µm prefiltration and UF without ozone. From the FTIR analysis of membrane fouling, results showed that the organic functional groups were aromatic rings and a few linear chain compounds of chromophore and auxochrome in dyestuff. So the tertiary treatment water may induce the colloidal fouling and organic fouling in the UF system. Experimental results also showed that preozonation could improve the tertiary treatment water and UF permeate quality. When the time of preozonation was increased more, improvement of water quality and effect of UF were enhanced more. When the ozone gas mass flow rate was 13.99 mg/min and the time for preozonation was 4 minutes, the removal efficiency of iron in the tertiary treatment water and the UF permeate was 62% and 100%, and meanwhile, the average particle size of the former decreased from 682nm to 380nm and the latter decreased from 400nm to 280nm, and the permeate flux increased from 60% to 80% of the initial flux, respectively. However, when increasing the preozonation time more, the water quality and the effect of filter were worse.
It was observed that when injecting into influent by ozone after blocked of the membrane, the permeate flux only increased from 60% to 80% of the initial flux. But, it was observed that when injecting into influent by ozone continuously, the permeate flux could maintained to 90% of the initial flux. It is demonstrated that the effect of the former is better than the latter. It was also observed that the permeate flux still maintained to 90% of initial permeate flux about 120 minutes from the beginning by ozone backwashing. According the above investigation, ozone in-line dosing and ozone backwashing are more suitable for inhibiting the membrane fouling.
On the whole, the reason why the permeate flux could be increased within ozonation were the molecular degradation and the particle destabilization. Moreover, ozonation could produce the oxygenated functional groups and increase hydrophile of tertiary treatment water. Because PVDF material was a hydrophobic membrane, so it could reduce the hydrophobic matter absorbed on the membrane surface. Comparing the FTIR analysis of fouling without and with ozone, the removal mechanism of organic fouling with ozonation was the destruction of aromatic ring and the breaking of macromolecule organic matters. The removal mechanism of inorganic fouling was also the ozonation of organic matter. The ozonation might produce the oxygenated functional groups that might couple with cations to form complexes and increase the solubility of scaling matters.
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Mosugelo, Keneetswe Lilian. "Effects of ozonation on cooling water systems." Thesis, 2010. http://hdl.handle.net/10539/8306.
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Cooling water systems are needed to dissipate heat. The mist from open system cooling towers has been implicated as a source of infections of Legionella pneumophila. As a result biocide is added to cooling water systems, but the addition of biocide worsens biofouling, scaling and corrosion. Increasing environmental pressure has resulted in a move away from biocides which are usually chlorine based chemicals, so that the use of ozone instead has recently been reported as a way of controlling microbiological growth. This study aims to compare the corrosion rates (using calculated and measured surface areas) of different metals exposed to chemically treated and ozone treated cooling water in an industrial cooling water system. The types of corrosion were also observed and recorded. The scales from different components of the cooling systems as well as scale from chemically and ozone treated D tower water were characterized qualitatively using X-ray diffraction (XRD), Thermo gravimetric Analysis (TGA) and Atomic Absorption Spectroscopy. The D tower is a cooling water circuit in which the cooling water is from the Vaal River. As expected, the stainless steel has the lowest corrosion rate of 0.000 milli inches/year followed by brass with 1.531 milli inches/year and lastly mild steel (2.098 milli inches/year). Water quality rather than the presence or absence of ozone determines the corrosion rate. This confirms the findings reported in the literature. Scale from chemically treated water contains many different compounds while scale from ozone treated contains only different polymorphs of CaCO3, which is present in the water source and magnesium calcite.
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Kuo, Po-Liang, and 郭柏良. "The Effect of MIEX Pretreatment on Ozonation." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/95922506458594077325.
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碩士<br>國立成功大學<br>環境工程學系碩博士班<br>94<br>The public water supplies of off-shore island of Taiwan encounter several problems, including salt water intrusion, high dissolved organic content in source water, high THM and red water in the distribution system. In order to abate these problems, the Water Works are contemplating upgrading the existing facilities. Including GAC filter is one of the options. Now, the dilemma is with only GAC, the regeneration frequency of GAC bed will be quite high, and, therefore, high costs. If GAC bed is preceded by ozonation, the regeneration frequency can be reduced, but there may be bromate problem, as there is high bromide concentration in the source water. Bromate is a suspected carcinogen, and local drinking water quality standards have set a limit for it.
As the Magnetic Ion Exchange Resin (MIEX) is able to remove both dissolved organic and bromide from water, in this study the MIEX was used as pretreatment of ozonation to see its effect on bormate and THM control. Both synthetic source water, which contained humic acid as model organic compound, and field source water from Kinmen Water Works were investigated.
The results show that MIEX has high NPDOC removal for both synthetic and field source waters. MIEX pretreatment also significantly reduced the ozone demand of the source waters. For bromate control, when the synthetic water was directly ozonated, the concentration of bromate formed was as high as 350 μg/L. However, the bromate concentration can be dropped to about 150 μg/L, if ozonation was preceded by MIEX. For field source water, the bormate concentration from direct ozonation was about 50 μg/L, still higher than that allows by local drinking water standards, which is 10 μg/L. With MIEX pretreatment, the bromate concentration of the ozonated water was lower than the detection limit of the instrument (MDL 4 μg/L). Therefore, MIEX pretreatment is effective for controlling bromate formation form ozonation of both synthetic source water and real Kinmenwater.
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CHIU, Chia-Ming, and 邱嘉明. "Removal of Sulfonamides and Macrolides by Ozonation." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/73151505382928239299.
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碩士<br>國立臺灣大學<br>環境工程學研究所<br>96<br>Nowadays, it have been already confirmed that antibiotics presence in various types of water environment. The main sources are pharmaceutical manufacturing, hospitals, dairy industry, fisheries and household sewage. The traditional biological treatment method of effluent has been unable to remove effectively. The removal of Sulfonamides and Macrolides with ozonation was conducted in this study.
Tylosin and Erythromycin has lower removal rate in multiple system than single system. Sulfamethoxazole, Sulfadimethoxine and Sulfamethazine have diverse removal efficiency in different phase of treatment. The addition of ten times of H2O2 (0.0961 mL , H2O2 30% by weight ) is beneficial to raise removal efficiency. Since multiple system of Erythromycin is concerned 90% removal in 9.6 minutes of O3/10X H2O2 treatment；20.5 minutes of O3 treatment. pH variation in the range between 3, 7 and 11 had similar result (pH 3＞pH 7＞pH 11) on Sulfamethoxazole, Sulfadimethoxine, Sulfamethazine and Tylosin degradation. For Erythromycin, the result of removal (pH 11≧pH 7＞pH 3) is different from the others. Removal efficiency of 5 target compounds in low concentration (400 ug/L) is similar to high concentration (40 mg/L). Therefore, the results for ozonation of pharmaceutical wastewater are excellent, the removal rate can achieve to 97% when react for 10 minutes and 99.5% of removal rate when react for 20 minutes . According to the LC/MS/MS, tentative determined intermediates of Sulfamethoxazole with mass equals to 99, 271, 284, 318 and 352 m/z.
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Han, Hung Shih, and 洪詩涵. "The Investigation of Free Radicals on Ozonation." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/29631817919302467508.
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碩士<br>東海大學<br>環境科學與工程學系<br>94<br>This study collected natural water samples from Te-Chi Reservoir which provides major domestic water supply in metropolitan central Taiwan area. The water sample organic contents were extracted and classified into humic acids (HAs, 29.7%), fulvic acids (FAs, 19.5%), hydrophobic neutrals (31.2%), hydrophobic bases (2.6%) and hydrophilic fractions (15.7%) by XAD-8 resins. Traditionally, raw water is disinfected by chlorination and some species of natural organic matters (NOMs), e.g. humic acids and their related substances are easily to form carcinogenic or mutagenic by-products. Those substances are often measured via the formation of cancer-causing potentials such as Trihalomethane Formation Potential (THMFP) and Haloacetic Acid Formation Potential (HAAFP) after chlorination. The result shows the FAs have the high THMFP and HAAFP value which was 40.1 and 67.0 μg/mg DOC, respectively. Furthermore, the HAs have the second high values which were 46.2 and 39.6μg/mg DOC individually.
The Te-Chi Reservoir raw water was ozonated to investigate the 2-step oxidation reaction mechanisms for this study. The on-line data of oxidation reduction potential (ORP), dissolved ozone (DO3) and pH were collected by an oscilloscope; the absorbance at 254 nm (A254) value was obtained from an on-line UV spectrophotometer (Carry50). The concentration of OH radicals was measured by HPLC (high performance liquid chromatography) in the presence of coumarin. The collected data, ORP, DO3, pH, OH radical and A254, are used to explain the ozone reaction mechanisms and also be used to develop a modified Nernst type model for ozonation. Fenton process was used to simulate the indirect free radical reaction in ozonation, therefore, the indirect hydroxyl radical oxidation contribution can be replaced by Fenton process. The ozone direct reaction and OH redicals indirect reaction contributed 37.1% and 62.9%, respectively.
The change of functional groups during ozonation was examined by using 13C NMR (13C nuclear magnetic resonance) and FTIR (Fourier-Transform infrared spectrophotometer) spectra. The functional groups can be found to be destructed by ozonation in this study.
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Ping, Yu Chang, and 于昌平. "Sequential Ozonation/Biodegradation to Treat Nitrophenolic Wastewater." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/12187417617057385222.
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博士<br>國立臺灣大學<br>環境工程學研究所<br>89<br>Among the processes developed for wastewater treatment, each has its limitations in applicability, effectiveness and cost. Integration of chemical and biological processes for recalcitrant or inhibitory contaminant treatment is an advantageous concept. The aim of chemical oxidation is to partially oxidize the recalcitrant contaminants to more easily biodegradable intermediates since a total mineralization may be not cost effective. Preoxidation of phenolic wastewasters by using ozone as the chemical oxidant has been found previously to be quite effective in enhancing their biodegradability and reducing their toxicity.
Ozone is a powerful oxidant among the commercially available oxidants used in water and wastewater treatment plants. In some cases organic compounds can be oxidized completely to CO2 and H2O with ozone, but such occurrences require relatively long ozone contact periods and relatively high ozone dosages. In most cases, organic compounds are oxidized to other materials which, as more and more oxygen atoms are incorporated during ozonation, become more refractory to continued ozonation. Such phenomena can be observed by following changes in TOC levels during ozonation. In such cases, ozone oxidation simply converts one organic compound into other organic compounds. However, the fact that ozone oxidation introduces oxygen into the original organic compound implies that the ozonated compounds now should be more biodegradable than the starting compounds. Indeed, preoxidation of wastewasters by using ozone as the chemical oxidant has been found previously to be quite effective in enhancing their biodegradability and reducing their toxicity. However, preozonated wastewaters may show some adverse effect on biological processes because some byproducts formed during oxidation appear to be more toxic than the original compound. Therefore, ozonation products play a key role in the total process, and careful analysis of the products should be carried out in advance.
"Biodegradability" is considered to be an index that can be used to evaluate the optimum conditions. As a result, to find the optimum condition of chemical pretreatment, methods for measuring biodegradability in these systems have been proposed by a number of authors as reviewed in the text. However, we found out some insufficiency and proposed several recommendations for future studies, two of which are to use bioreactors instead of biodegradability and to study reaction intermediates. To predict the behavior in actual combined processes, there should be more efforts done to reveal if these short-term biodegradability tests could represent the results of those long-term biological processes. In addition, those gross parameters of biodegradability and toxicity, such as BOD5 or EC50 provide little information about the ultimate fates of the reaction intermediates. In previous literatures, although a few researches ran biological processes, which mimicked actual processes, none of them study the conversion of reaction intermediates that the bioreactor received from the chemical pretreatment.
In order to minimize complexity, ozonation and a single compound p-nitrophenol were chosen as the model chemical pretreatment and the target compound in our study. Ozonation of organic compounds doesn’t generate sludge and usually produced oxygenated organic materials instead of introducing any other atom into it. These make us more easily to operate and predict the reaction intermediates. p-Nitrophenol, with the annual production of 20 million kg ,has been listed as "priority pollutants" by the U.S. Environmental Protection Agency and recommended restricting their concentrations in natural waters to < 10 ng/l. First, this study was undertaken to examine the reaction between ozone and p-nitrophenol. The appearance and disappearance of various reaction intermediates and products will be analyzed quantitatively over the course of time using HPLC. Several intermediates formed before and after ring-opening of p-niitrophenol were quantitatively determined by HPLC in our work. GC/MS and electrospray ionization mass spectrometry (ESI-MS) were also used to help establish the reaction pathway. The purpose of this part is to develop an understanding of the ozonation process for nitrophenolic compounds. This research not only finds out the ozonation products but also focuses on the biological process. Sequencing Batch Reactors (SBRs) were chosen to be the subsequent biological system. The SBR, because of its batch nature, can let us observe substrate degradation by following changes of the concentrations of all compounds in the bioreactor. In conclusion, this study was undertaken to examine the ultimate fates of reaction intermediates in integrated ozonation-biotreatment process. The appearance and disappearance of various reaction intermediates and products will be analyzed quantitatively over the course of time using HPLC. Microtox toxicity test and spectrometric analysis were also used to help establish the degradation scheme. Different from any previous researches concerning combined processes, a detailed community-level characterization of microbial biomass from SBRs, was carried out using BIOLOG redox-based carbon source utilization assay. The purpose of this paper was undertaken to examine if these short-term biodegradability tests could represent the results of those long-term biological processes.
Ozonation of p-nitrophenol followed by lab-scale SBRs, rather than biodegradability tests, was conducted in the research. By observing the degradation of intermediates, the elimination of DOC, color and toxicity, and the variation of microbial ecologies, several conclusions can be drawn as followed: First, ozonation of p-nitrophenol generates nonbiodegradable compounds which might include polymerized intermediates, ring-opening products with nitro groups, and metabolic dead-end products. Second, there was no Microtox toxicity detected from any biological effluents, which means that either those nonbiodegradable compounds comprising the appreciable amount of residual DOC are nontoxic materials, or their concentration is not high enough to show toxicity. Third, the microbial ecology analysis showed that different ozonation times generate distinct amounts of intermediates and lead to dissimilar microbial communities. Finally, from the results of the community metabolism pattern and the overall system efficiency, we found that adverse effects will be brought about by improper ozonation. Instead of finding out an optimum ozonation time, a least efficient condition was observed. This implies that the result of the biodegradability test, which reflect the initial situation when a group of microorganisms were first exposed to some new substances, will not always guarantee the same result in a biological treatment system.
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LU, YI-MIN, and 陸一民. "The study of cyanide destruction by ozonation." Thesis, 1991. http://ndltd.ncl.edu.tw/handle/65726551963049895723.
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