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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Evaluation of pharmaceutical removal in seven WWTPs : Efficiency of different treatment technologies / Utvärdering av läkemedelsrening i sju olika avloppsreningsverk : Olika reningsteknikers effektivitet

Munkhammar, Viktor January 2023 (has links)
Wastewater treatment plants (WWTPs) are originally not constructed to remove pharmaceuticals from the wastewater. Biological treatment technologies used in many WWTPs today, e.g., activated sludge, MBBR and trickling filters, can, however, remove some pharmaceuticals well. Advanced treatment technologies, like ozonation, can be used as a complement to biological treatment for an even better removal. Käppala WWTP is not required to remove pharmaceuticals today, but is obligated to follow the development of advanced treatment technologies and prepare to implement one in the future. Additionally, a new wastewater treatment directive is under development with stronger regulations of pharmaceutical removal. Because of this, it is important to gather information about removal efficiencies for different treatment technologies in Käppala and other WWTPs. In this project, direct injection-UHPLC-Orbitrap-MS/MS was used to analyze wastewater from seven different WWTPs, including Käppala, with the aim to detect as many pharmaceuticals as possible. The removal efficiencies for 59 identified compounds, most of them pharmaceuticals, were used to evaluate the WWTPs and their treatment technologies. 55 of these compounds were detected in Käppala WWTP while 48 were detected in all seven WWTPs. In Käppala WWTP, around half of all compounds were removed with less than 20 %, including most of the compounds that is proposed to be regulated in the new wastewater treatment directive. This highlights the need for Käppala WWTP to introduce new treatment technologies. Two Swiss plants with ozonation had a removal efficiency > 80 % across the whole plant for 79 % and 67 % of the compounds respectively. In the WWTPs that lacked advanced treatment technologies only 12-33 % of the compounds had a removal > 80 %. One compound, chlorothiazide, did however increase 30 times across the plants with ozonation treatment. The trickling filter in one WWTP barely removed any compound with more than 20 % and was thereby the biological treatment technology with lowest removal efficiency. Activated sludge without N-removal also had a slightly lower removal of pharmaceuticals compared to activated sludge with N-removal and MBBR, possibly due to a shorter hydraulic retention time (HRT) and sludge retention time (SRT).
72

Removal of pharmaceutical residues from wastewater by oxidation with ozone / Rening av vatten från läkemedelsföroreningar genom ozonbehandling

Söderström, Frida January 2021 (has links)
Avloppsreningsanläggningar är idag utformade för att rena bort föroreningar i form av organiskt material, suspenderade fasta ämnen och växtnäringsämnen (exempelvis fosfater och nitrater). Myndighet i Sverige har satt upp restriktioner och lagar gällande hur mycket av de olika föroreningarna som det är okej att utgående vatten innehåller. En typ av föroreningar som dock inte blivit undersökt och som inte har lika tydliga restriktioner och utsläppslagar är utsläpp av läkemedelsrester och aktiva läkemedelssubstanser. Den största andelen av läkemedelsrester som återfinns i avloppsvatten är på grund av mänsklig konsumtion. Människan har under evolutionen alltid strävat efter att hitta nya metoder för att leva längre, må bra och undvika smärta. Under de senaste årtiondena har konsumtionen av läkemedel ökat, detta på grund av behandling av åldersrelaterade och kroniska sjukdomar, i kombination med en ändrad och mer generös receptutskrivning från sjukhusen.  Läkemedlen som vi konsumerar kommer inte att brytas ner helt av våra kroppar, och restprodukterna kommer utsöndras vida urinen. Urinen kommer sedan, vi avloppen, komma till ett av de lokala avloppsreningsverken, som idag inte har förmåga att rena bort de aktiva läkemedelssubstanserna från vattnet. Det kommer sedan att påverka omgivande vattendrag, djurliv och på lång sikt även ekosystemen.  Tidigare studier har genomförts med syfte att hitta miljövänliga och hållbara metoder för att rena vattnet från mikroföroreningar och läkemedelsrester. En av teknikerna som undersökts är oxidation och adsorption processer. Ett sätt att genomföra oxidation är genom ozonering, som genom sin höga oxidationspotential och miljövänliga slutprodukter i form av bland annat syre gör den till ett miljövänligt alternativ. Vad gäller adsorption processer så är aktivt kol en av de vanligaste teknikerna som används idag och det har visat på goda resultat. Ett vanligt förekommande problem med aktiva kolfilter är att det måste bytas ut när det blivit mättade vilket både kostar pengar, arbetskostnader och en avstannad vattenprocess.  Denna avhandling behandlar utvärdering och process optimering av vattenrening vid behandling av ozon med avseende att rena vatten från aktiva läkemedelssubstanser. För att göra detta har två pilotanläggningar för vattenrening, placerade på två olika platser i Sverige (plats 1 och plats 2) undersökts och optimerats. Båda systemen är utrustade med ett sandfiltersteg, ozonerigssteg anst ett avslutade poleringssteg i form av aktivkolbädd. De två olika systemen är kopplade så inkommande vatten är utgående vatten från likat avloppsreningsverk. Undersökta variabler är injicerad ozonhalt (uteffekt baserat på ozongeneratorns kapacitet) och i ett av fallen, vattenflödet genom systemet. Syftet med arbetet var att hitta optimala driftförhållande med avseende på reducerad mängd läkemedelssubstanser i vatten och energiförbrukning.  Resultaten visade att den parameter som influerade resultatet mest var mängden ozon som injicerades till systemet. Systemet som var installerat på plats 2 var det mest effektiva baserat på både energiförbrukning per m3 vatten och med avseende på reningsgraden på vattnet. Systemet rena vattnet från läkemedelssubstanser upp till mellan 95–100%, vid ett vattenflöde på 16 m3/h och en uteffekt av ozongeneratorn på 75%.  Systemet på plats 1 hade en halverad ozonkapacitet jämfört med systemet på plats 2 och visade inte på fullt lika effektiv rening. Vattnet som bäst renat till 80%, vid ett vattenflöde på 2,5 m3/h och en uteffekt av ozongeneratorn på 100% (motsvarar 50% på plats 2). / Wastewater treatment plants today are designed to reduce pollutants in the form of organic material, suspended solids, plant nutrients (phosphates and nitrates) and microbes from the water. Governments have set up restrictions and laws around in what amount release of different pollutants is acceptable or not. But one type of pollutant that have not been investigated to the same degree is the micropollutants such as pharmaceuticals or active pharmaceutical ingredients (APIs). The biggest amount of APIs release to water is due to human consumption of medicine. Humans have during the evolution strived to find new ways to live longer, stay healthier and avoid pain. Over the last decade there has been an increased consumption of medicine, due to the need to treated ageing related and chronic diseases, together with a change in the clinical practice leading to a more generous prescription approach.  The APIs that we consume will not be totally decomposed in our body, which means that we sooner or later will exude it in form of example urine. The urine will end up in the local WWTP, which today, does not have the ability to reduce APIs in large amount. Due to this, release of APIs to surrounding watercourse will come to affect the animals and eco-system.  Many studies have been done with a goal to find an environmentally friendly way to reduce micropollutants from the wastewater. One of the techniques that has been investigated is oxidation (e.g., ozonation) and adsorption (e.g., activated carbon) processes. Ozonation is an ideal technique due to the high oxidation potential of ozone, environmentally friendly end-products (e.g. oxygen) and low sludge production. Several reports elucidated that application of ozonation for wastewater can have a reducing effect of APIs, and a more studied technique for removal of micropollutants and APIs is activated carbon (AC). But AC has some common struggle, one example is that it works as a filter and that it due to adsorption can be saturated.  The project contained evaluation and process optimization of water purification by oxidation with ozone with aim to purifying water from APIs. To do this, two pilot plants for water purification, located in two different locations in Sweden (location 1 and location 2) will be evaluated and optimized. Both systems are equipped with a sand filter, ozonation step and a polishing step of activated carbon. The two different systems are connected so that incoming water to the system, is outgoing water from a local wastewater treatment plant. The variables evaluated are injected ozone concentration (output power based on the capacity of the ozone generator) and in one of the cases, the water flow through the system. The purpose of the work was to find optimal operating conditions regarding reduced amount of drug substances in water and energy consumption.  The system installed at location 2 is the most effective system from a perspective of both micropollutants reduced and energy used per m3. The API reduction is between 95-100% for the outgoing water and the ozonation step stands for 95-100% of that reduction, which increases the lifetime of the GAC filter. For optimal process settings a water flow of 16 m3/h and an out effect of 75% from the ozone generator was determined.  At location 1 the APIs reduction achieved was 80% after ozonation and 100% after the GAC filtration, and the process settings were 100% out effect (correspond to 50% at location 2) on the ozone generator and a water flow of 2.5 m3/h.
73

REMOVAL OF EMERGING CONTAMINANTS FROM AQUEOUS SOLUTION BY OZONE -BASED PROCESSES

Rani, Rupam January 2013 (has links)
The presence of emerging contaminants (ECs) in water and wastewater systems has become a subject of significant concern worldwide. These emerging contaminants are complex organic molecules which potentially affect human health and environment. Conventional wastewater treatment plants are unable to completely remove these contaminants from water and therefore can discharge them into environment. The need to develop effective methods for ECs removal is essential. This study assess the potential of ozone based advanced oxidation processes (AOP) to oxidize number of emerging contaminants. Different combinations of ozone with hydrogen peroxide and sodium persulfate were tested. For this study 1-4, dioxane, perfluorinated compounds (PFCs), N,N-Diethyl-metatoluamide, and three pharmaceuticals sulfamethoxazole, trimethoprim and carbamazepine have been selected. The effect of different process parameters such as chemical dosages, ozone weight percent, ozone flow rates, etc. on destruction of ECs were examined. It was observed that 1, 4-dioxane were persistent to direct ozone reaction, however were easily oxidized by hydroxyl radical. However, ozonation was solely very effective (> 99 %) in removing pharmaceuticals such as sulfamethoxaole, trimethoprim and carbamazepine. It was not very efficient for the removal of perfluorinated compound and N,N-Diethylmeta-toluamide. The operational conditions were optimized for maximum removal of every compound and their influence on the degradation process is discussed. / Civil Engineering
74

Etude d'un procédé d'ozonation catalytique pour l'élimination des micropolluants dans les effluents urbains / Etude d’un procédé d’ozonation catalytique pour l’élimination des micropolluants dans les effluents urbains

Crousier, Claire 10 December 2015 (has links)
Les travaux menés au cours de cette thèse ont pour objectif d’étudier l’applicabilité du procédé d’ozonation catalytique TOCCATA® au traitement avancé d’eaux résiduaires urbaines pour le contrôle des émissions en micropolluants. Ce travail couvre la détermination des propriétés physico-chimiques, structurelles et de réactivité de deux catalyseurs et l’optimisation de leur conditionnement pour le procédé d’ozonation catalytique. La caractérisation hydrodynamique du réacteur à co-courant ascendant triphasique en lit fixe utilisé pour la mise en œuvre du procédé a été également réalisée. Les processus élémentaires impliqués dans le procédé ont ensuite été étudiés séparément : transfert gaz-liquide, adsorption, ozonation simple et interaction ozone/matériau. Enfin l’ozonation catalytique a été étudiée vis-à-vis de l’élimination de la matière organique des eaux usées réelles. L’ozonation catalytique se montre moins sélective que l’ozonation simple et améliore le procédé en termes de transfert d’ozone et d’élimination du carbone organique. Des mécanismes et des lois cinétiques pour chacun des processus élémentaires ont été déterminés et une loi de vitesse globale de premier ordre pour le procédé d’ozonation catalytique est proposée. L’étude de l’influence de différentes variables opératoires a été effectuée en vue de l’optimisation du procédé. L’investigation a ensuite été élargie à l’élimination de micropolluants spécifiques (carbamazépine, diuron, kétoprofène, diclofénac, naphtalène) appliquée à des eaux synthétiques, ainsi qu’à des eaux résiduaires urbaines réelles. La plupart des composés sont dégradés après application d’une faible dose d’ozone par le procédé. L’étude de leurs propriétés et de leur affinité avec le système d’ozonation catalytique a permis d’expliquer leurs comportements. / This thesis aimed to study the application of the TOCCATA® catalytic process to urban wastewaters treatment in order to control micropolluant emissions. This work first focused on physico-chemical, structural and reactional properties of two catalysts and on the optimization of their conditioning for the use in the catalytic process. The hydrodynamic characterisation of the fixed bed triphasic co-current upflow reactor used for this study was realized. Elementary processes involved in the process were studied separately: gas-liquid transfer, adsorption, single ozonation, ozone/catalyst interactions. Catalytic ozonation was then investigated for the elimination of organic matter contained in real urban wastewaters. Catalytic ozonation appeared to be less selective than single ozonation and to improve the process in terms of ozone transfer and organic carbon removal efficiency. Mechanisms and kinetic laws were determined for each elementary process and a global first order kinetic law was proposed for catalytic ozonation. The study of various operating conditions (liquid and gas flows, ozone dose …) was conducted in order to optimize the process efficiency.Investigations were then extended towards specific micropollutants elimination (carbamazepine, diuron, ketoprofen, diclofenac, naphtalene) onto synthetic waters as well as real urban wastewaters. Most of the compounds were eliminated with low dose ozonation by the TOCCATA® catalytic ozonation process. The properties of the micropollutants and their affinities with the catalytic ozonation system were studied in order to explain their behaviours.
75

Développement de méthodes analytiques pour la détection et la quantification de traces de produits pharmaceutiques dans les eaux du fleuve Saint Laurent

Garcia Ac, Araceli 09 1900 (has links)
Le présent projet vise à documenter la nécessité d’augmenter notre connaissance de la présence des contaminants organiques tels que les médicaments dans l’environnement et d’évaluer leur devenir environnemental. On a étudié la présence de composés pharmaceutiques dans différents échantillons d'eau. On a focalisé nos efforts spécialement sur les échantillons d'eau de l'usine d'épuration de la Ville de Montréal et ses effluents, les eaux de surface avoisinantes et l’eau du robinet dans la région de Montréal. Pour ce faire, on a tout d’abord développé deux méthodes analytiques automatisées basées sur la chromatographie liquide avec extraction en phase solide (SPE) couplée à la chromatographie liquide couplée à la spectrométrie de masse en tandem (LC-MS/MS). On a également étudié les performances des trois techniques d'ionisation à pression atmosphérique (API), pour ensuite les utiliser dans la méthode analytique développée. On a démontré que l'ionisation par électronébulisation (ESI) est une méthode d'ionisation plus efficace pour l'analyse des contaminants pharmaceutiques dans des échantillons de matrices très complexes comme les eaux usées. Une première méthode analytique SPE couplée à la LC-MS/MS a été développée et validée pour l'étude des échantillons complexes provenant de l'usine d'épuration de la Ville de Montréal et des eaux de surface près de l'usine. Cinq médicaments de prescription ont été étudiés: le bézafibrate (un régulateur de lipides), le cyclophosphamide et le méthotrexate (deux agents anticancéreux), l'orlistat (un agent anti-obésité) et l’énalapril (utilisé dans le traitement de l'hypertension). La plupart de ces drogues sont excrétées par le corps humain et rejetées dans les eaux usées domestiques en faisant par la suite leur chemin vers les usines municipales de traitement des eaux usées. On a pu démontrer qu'il y a un faible taux d’élimination à l'usine d'épuration pour le bézafibrate et l'énalapril. Ces deux composés ont aussi été détectés dans les eaux de surface sur un site à proximité immédiate de la décharge de l’effluent de la station d'épuration. i En observant la nécessité de l'amélioration des limites de détection de la première méthode analytique, une deuxième méthode a été développée. Pour la deuxième méthode, un total de 14 contaminants organiques, incluant trois agents anti-infectieux (clarithromycin, sulfaméthoxazole et triméthoprime), un anticonvulsant (carbamazépine) et son produit de dégradation (10,11-dihydrocarbamazépine), l'agent antihypertensif (enalapril), deux antinéoplastiques utilisés en chimiothérapie (cyclophosphamide et méthotrexate), des herbicides (atrazine, cyanazine, et simazine) et deux produits de transformation de l’atrazine (deséthylatrazine et déisopropylatrazine) ainsi qu’un agent antiseptique (triclocarban). Ces produits ont été quantifiés dans les eaux de surface ainsi que dans l’eau du robinet. L'amélioration des limites de détection pour cette méthode a été possible grâce à la charge d'un volume d'échantillon supérieur à celui utilisé dans la première méthode (10 mL vs 1 mL). D'autres techniques de confirmation, telles que les spectres des ions produits utilisant une pente d’énergie de collision inverse dans un spectromètre de masse à triple quadripôle et la mesure des masses exactes par spectrométrie de masse à temps d’envol, ont été explorées. L'utilisation d'un analyseur de masse à temps d’envol a permis la confirmation de 6 des 14 analytes. Finalement, étant donné leur haute toxicité et pour évaluer leur persistance et leur transformation au niveau du traitement des eaux potables, la cinétique d'oxydation du cyclophosphamide et de méthotrexate avec l'ozone moléculaire et des radicaux OH a été étudiée. Les constantes de dégradation avec l'ozone moléculaire ont été calculées et la qualité de l'eau après traitement a pu être évaluée. Le rendement du processus d'ozonation a été amélioré pour la cyclophosphamide dans les eaux naturelles, en raison de la combinaison de réactions directes et indirectes. Cette étude a montré que l'ozone est très efficace pour oxyder le méthotrexate mais que le cyclophosphamide serait trop lent à s’oxyder pour un traitement efficace aux conditions usuelles de traitement de l’eau potable. / This project aims to document the need to increase our knowledge of organic contaminants such as pharmaceuticals in the environment and to assess their environmental fate. We studied the presence of pharmaceutical compounds in different water samples. We studied their presence in wastewater samples from the treatment plant of the City of Montreal, effluents, surface and tap water. To do this we developed two analytical methods based on solid phase extraction (SPE) coupled to liquid chromatography -tandem mass spectrometry (LC-MS/MS). . The performance of three atmospheric pressure ionization (API) techniques was also studied for their subsequent use in the developed method. It was demonstrated that electrospray ionization (ESI) is a more effective ionization method for the analysis of pharmaceutical contaminants in samples as complex as wastewaters. A first analytical LC-MS/MS method, was developed and validated for the investigation of samples from the wastewater treatment plant and surface waters near the plant of Montreal. Five prescription drugs were studied: bezafibrate (lipid regulator), cyclophosphamide, and methotrexate (two anticancer agents), orlistat (an anti-obesity agent) and enalapril used in the treatment of hypertension. Most of these drugs are excreted by the human body in high percentages and released into domestic wastewaters, making their way to the municipal wastewater treatment plants. It was demonstrated that there is a low rate of elimination at the wastewater treatment plant for bezafibrate and enalapril. These two compounds were also detected in surface waters on a site close to the discharge of the treatment plant effluents. For this first analytical method we observed the necessity of improvement of the detection limits of the method. A second method was then developed to improve the detection limits and to study a total of 14 organic contaminants, including three antiinfective agents (clarithromycin, sulfamethoxazole and trimethoprim), an anticonvulsant (carbamazepine) and its degradation product 10,11-dihydrocarbamazepine, the iii antihypertensive agent (enalapril), two antineoplastic (methotrexate and cyclophosphamide), herbicides (atrazine, cyanazine, and simazine) and two transformation products of atrazine (desethylatrazine and déisopropylatrazine) and an antiseptic agent (triclocarban). These products were quantified in surface water and tap water. The improvement of the detection limits of this method was possible due to the loading of a greater sample volume than that used in the first method (10 mL vs 1 mL). Other confirmation techniques, such as the data-dependent reverse energy ramp scan on a triple quadrupole and accurate mass measurements on a time-of-flight mass spectrometer were explored. Using time-of-flight mass spectrometer determinations allowed the confirmation of six of the 14 analytes. Finally, due to their toxic properties, the oxidation kinetics of cyclophosphamide and methotrexate with molecular ozone and OH radicals was studied in bench scale. The degradation constants with molecular ozone were calculated and the water quality after treatment was assessed. The overall process performance was improved for cyclophosphamide in natural waters, due to the combination of direct and indirect reactions. The study showed that ozone is very effective for the oxidation of methotrexate, but cyclophosphamide is too slowly oxidized for an effective drinking water treatment under usual conditions.
76

Développement de méthodes analytiques pour la détection et la quantification de traces de produits pharmaceutiques dans les eaux du fleuve Saint Laurent

García Ac, Araceli 09 1900 (has links)
No description available.
77

Sous-produits de chloration dans les eaux de piscine - Effet de l'ozonation / Disinfection by-products in chlorinoted swimming pool waters - Effect of ozonation

Freyfer, Diab Adams 12 December 2012 (has links)
Ce travail a été consacré à l'étude des sous-produits de désinfection formés lors de la chloration des eaux de piscine publiques. En effet, parallèlement à son action désinfectante, le chlore réagit sur les composés organiques et minéraux introduits dans l'eau des bassins par les baigneurs (urine, sueur, ...) pour former des sous-produits indésirables (chloramines et composés organohalogénés).Des analyses d'urée, principal composé précurseur de chloramines inorganiques, ont été effectuées dans une cinquantaine d'eaux de piscine. Les concentrations mesurées ont été comprises entre 0,14 et 3,67 mg/L (valeur moyenne : 1,08 mg/L ; écart-type : 0,70 mg/L). L'étude de la réactivité du chlore sur l'urée (cinétique et consommation de chlore) effectuée sous différentes conditions expérimentales a mis en évidence une très grande stabilité de l'urée en présence de chlore libre dans les eaux de piscines.Les analyses de sous-produits de chloration ont démontré que l'hydrate de chloral représente l'un des sous-produits de chloration majoritaire avec les acides dichloroacétique et trichloroacétique. Cette étude a aussi permis de déterminer la constante cinétique d'hydrolyse de l'hydrate de chloral dans l'eau, l'influence du pH et de la température sur la vitesse d'hydrolyse, ainsi que les potentiels de formation d'hydrate de chloral à partir de quelques constituants de l'urine.La dernière partie de ce travail a porté sur l'étude de la réactivité de l'ozone sur le chlore et sur des sous-produits de chloration ainsi que sur l'étude de l'incidence d'une préozonation des eaux de piscines (en absence et en présence de chlore libre) sur la formation des sous-produits organohalogénés lors d'une post-chloration. / The aim of this work was to study of the formation of disinfection by-products during the chlorination of public swimming pools water. In parallel to its disinfecting action, chlorine reacts with organic and inorganic compounds introduced into the swimming pool water by bathers (urine, sweat, ...) to form undesirable by-products (chloramines and organohalogenated matters).A statistical study of the presence of urea, the major component of urine and sweat, and the main precursor compound of inorganic chloramines, in public swimming poolwater has been made. Measured concentrations were between 0.14 and 3.67 mg/L (mean value: 1.08 mg/L, s.d: 0.70 mg/L). The study of the reactivity of chlorine with urea (kinetic and chlorine consumption) made under different experimental conditions, showed a very high stability of urea in the presence of free chlorine in the pools water.Analysis of chlorination by-products showed that chloral hydrate, with the dichloro and the trichloroacetic acids, is one of the major chlorination by-products found. This study also determined the kinetic rate constant of hydrolysis of chloral hydrate in water, the influence of the pH and the temperature on the rate of hydrolysis and the potential of chloral hydrate formation from some constituents of the urine.The last part of this work was focused on the study of the reactivity of ozone on chlorine and some disinfection by-products, as well as the study of the impact of preozonation of swimming pools water (in absence and presence of free chlorine) on the formation of organohalogenated by-products during a post-chlorination.
78

Dégradation du paracétamol et de la ciprofloxacine par des procédés d'oxydation avancés dans des eaux usées / Degradation of paracetamol and ciprofloxacin by advanced oxidation processes in wastewater.

González-Labrada, Katia 20 December 2018 (has links)
Ce travail étudie la faisabilité de différents procédés d’oxydation avancée (POAs) pour le traitement d’eaux usées industrielles. Le secteur visé est l’industrie pharmaceutique, les essais ont été menés sur des eaux synthétiques contenant deux molécules modèles: le paracétamol et la ciprofloxacine. Les procédés étudiés dans ce travail sont l’ozonation, la sonochimie, le traitement par radiation gamma et la dégradation par radiation ultraviolet. Ces techniques sont envisagées en mono-traitement ou en combinaison avec des oxydants et/ou des catalyseurs (peroxyde d’hydrogène, réactif de Fenton et zéolite Fe/MFI). Pour chaque procédé, l'influence de différents paramètres opératoires est analysée et interprétée dans l'objectif de déterminer les meilleures conditions pour la conversion et la minéralisation du chaque polluant. Parmi les paramètres étudiés se trouvent le pH, la concentration en oxydant, la concentration du catalyseur, la dose de la radiation gamma, la fréquence et la puissance ultrasonore. Des effets synergiques importants sont trouvés pour l’ozonation catalytique et pour le photo-Fenton par rapport aux procédés seuls. D’un point de vue purement énergétique, les traitements les plus efficaces sont l’oxydation radio- Fenton et l’oxydation photo-Fenton. Sur la base de ces résultats, un photo-réacteur solaire à recirculation est mis en oeuvre pour traiter par oxydation photo-Fenton des solutions synthétiques préparées avec un mélange de paracétamol et de ciprofloxacine dans l’eau du robinet mais aussi avec des eaux usées réelles dopées avec les deux composés. Dans les deux cas, la dégradation des molécules dépasse 95% dans les 15 premières minutes et la minéralisation dépasse 55% en 180 minutes. / In this work, the feasibility of paracetamol and ciprofloxacin degradation by different advanced oxidation processes (AOPs) was investigated. These molecules are representative of pharmaceutical pollutants found in wastewater. The used processes were the ozonation, the high frequency ultrasound, the gamma radiation and the ultraviolet radiation, alone or in combination with oxidizers and/or catalysts (hydrogen peroxide, Fenton’s reagent and zeolite Fe/MFI). The influence of different operations parameters (pH, oxidant concentration, catalyst concentration, gamma radiation dose and ultrasonic power and frequency) for each processes were studied, in order to determine the optimal operating ranges for the degradation and mineralization of the pharmaceuticals pollutants. Results showed marked synergistic effects by combining individual processes with hydrogen peroxide or Fenton’s reagent, being the most important synergy factors those corresponding to the heterogeneous catalytic ozonation and photo-Fenton processes. Taking into account the energy consumption, the mineralization and the synergy factor, the most effective treatments were radio-Fenton oxidation and photo-Fenton oxidation. Optimal conditions for photo-Fenton oxidation were studied in an open channel reactor at bench scale in tap water and in a real matrix from a municipal wastewater treatment plant. Samples were spiked with a mixture of the pharmaceuticals. In both cases 95% degradation within the first 15 minutes was achieved and its mineralization exceeded 55% in three hours.
79

Tratamento de Efluente de Suinocultura com Tratamento Físico-Químico (Coagulação e Precipitação e Ozonização) e Químico (Ozonização catalítica e Fenton) / Treatment of Swine Effluent with Physical-Chemical (Coagulation and Precipitation and Ozonization) and Chemical (Catalytic Ozonation and Fenton) Treatment

Giron, Mariana Paiva Batagini 22 April 2019 (has links)
Os dejetos suínos são caracterizados pelo elevado teor de sólidos, matéria orgânica, nutrientes (nitrogênio e fósforo), substâncias patogênicas, cor e odor, e, desta forma, se não forem corretamente tratados, tornam-se um poderoso poluidor ambiental e podendo acarretar risco potencial à saúde humana e ao meio ambiente. Neste contexto, surgem os chamados Processos Oxidativos Avançados (POA), que são métodos eficientes para a degradação de compostos orgânicos. No presente trabalho foi empregado um processo híbrido (físico e químico), principalmente a utilização da ozonização, potencializando o processo de tratamento com outros reagentes relevantes no tratamento de águas residuárias de suinocultura do Instituto Federal do Rio de Janeiro (IFRJ), campus Pinheiral-RJ. A caracterização do efluente de suinocultura in natura, pré-tratado e tratado foi realizada empregando-se métodos consolidados [DQO, COT, DBO5, surfactantes aniônicos, óleos e graxas, fenol, peróxido de hidrogênio, Nitrogênio (orgânico), Sólidos (ST, STV e STF) e elementos metálicos]. Primeiramente, somente processos químicos exploratórios de ozonização (sem e com Fe2+) foi testado e, devido à pouca eficiência deste tratamento (25,3 % e 21,1 % para COT e DQO, respectivamente), foi necessário um pré-tratamento físico-químico por meio da ozonização com cal hidratada, avaliando fatores como quantidade de cal, quantidade de floculante polimérico e tempo reacional, com resultados de 43,7 % para COT e 42,9 % para DQO. Posteriormente, o sobrenadante deste pré-tratamento (O3 + cal) foi usado em novos experimentos utilizando o processo de ozonização combinado com Fenton partindo do efluente pré-tratado, resultando na redução de 95,6 %, para COT, e 96,3 % para DQO, comparados com o efluente pré-tratado com ozônio e cal. A estimativa de custos operacionais e reacionais para o tratamento combinado (POA com Cal/POA com Fenton) totalizou em R$ 0,1016 por litro de efluente tratado. Também, os resíduos provenientes dos tratamentos POA com cal e POA com Fenton mostraram-se ser potenciais fertilizantes nos testes preliminares seguindo as normas da EMBRAPA, sendo testados para o solo Argissolo e para a espécie de planta Schinus molle. Após um período de 60 dias, visualmente as plantas com as presenças do fertilizante de Cal e fertilizante Cal + Ferro apresentaram maior crescimento. / Swine manure is characterized by high solids content, organic matter, nutrientes (nitrogen and phosphorus), pathogenic substances, color and odor. If not properly treated, they become a powerful environmental polluter and may result in a potential risk to human health and the environment. In this context, arise the Advanced Oxidation Processes (POAs), which are efficient methods for the degradation of organic compounds. In the present work a hybrid process (physical and chemical) was employed, mainly the use of ozonation, potentiating the treatment process with factors of greater relevance in the treatment of swine wastewater of Instituto Federal do Rio de Janeiro (IFRJ), campus Pinheiral-RJ. The in natura and treated swine effluent characterization was carried out using consolidated methods [COD, COT, BOD5, anionic surfactants, oils and greases, phenol, hydrogen peroxide, Nitrogen (organic), Solids (ST, STV and STF) and metal elements]. First, only ozonation chemical processes (without and with Fe2+) were tested and, due to the low efficiency of this treatment (25.3% and 21.1% for TOC and COD, respectively). It was necessary a physical-chemical pretreatment using ozonation with hydrated lime evaluating factors such as amount of lime, amount of polymeric flocculant and reaction time, with results of 43.7% for TOC and 42.9% for COD. Afterwards, the supernatant from this pretreatment (O3 + lime) was used in new experiments using the ozonation process combined with Fenton starting from the pretreated effluent, resulting in reductions of 95.6% for TOC and 96.3% for COD, compared to the effluent pretreated with ozone and lime. The estimate of operational and reactional costs for the combined treatment (POA with Lime/POA with Fenton) totaled R$ 0.1016 per liter of treated effluent. In addition, the residues from the POA with Lime and POA with Fenton treatments proved to be potential fertilizers in the preliminary tests following EMBRAPA standards, being tested for the Argissolo soil and for the Schinus molle plant species. After a period of 60 days, visually the plants with the presence of Lime fertilizer and Lime + Iron fertilizer showed higher growth.
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Ozonização: uma alternativa para clarificação do caldo de cana-de-açúcar. / Ozonation: an alternative for clarification of sugarcane.

Fonseca, Christiane Reis 16 February 2017 (has links)
A agroindústria canavieira no Brasil é um setor de destaque por exercer papel fundamental na economia, sendo responsável pela geração de empregos, renda e produtos e subprodutos de interesse como, açúcar, etanol e energia. A clarificação do caldo de cana é um dos processos unitários mais críticos das usinas açucareiras. Atualmente, o açúcar brasileiro é clarificado utilizando-se o processo de contato com dióxido de enxofre, conhecido como sulfitação. Existe, porém, uma tendência mundial na redução do uso de compostos à base de enxofre nos alimentos, devido a possíveis efeitos nocivos à saúde. Além disso, a queima de enxofre elementar nas usinas é fonte de emissões de gases sulforosos, desconforto no ambiente de trabalho das fábricas e corrosão de metais nas instalações industriais. Dessa forma, alternativas à sulfitação têm sido avaliadas, entre as quais a ozonização, processo que carece de estudos fundamentais. No presente trabalho foram avaliados parâmetros de transferência de massa do ozônio, tanto em água como em solução modelo contendo sacarose e compostos fenólicos presentes no caldo de cana (ácidos ácido p-cumárico, cafeico, siríngico e clorogênico, além do flavonoide quercetina). A partir destes experimentos foi verificado que a ozonização da mistura de fenólicos é caracterizada por uma reação lenta devido à presença de ozônio dissolvido no meio. Observou-se que não houve degradação da sacarose e os principais intermediários identificados foram ácidos orgânicos, não ocorrendo, porém, mineralização completa dos compostos fenólicos. Após este estudo foram realizados experimentos de ozonização com caldo de cana seguindo um projeto experimental com o objetivo de verificar a remoção de cor ICUMSA e também de compostos fenólicos. Verificou-se importante remoção de cor (80%) após duas horas de ozonização a 40 oC, empregando-se 30 mg L-1 de ozônio no gás alimentado à vazão de 0,5 L min-1. Por outro lado, obtiveram-se 50% de remoção de compostos fenólicos para concentração de O3 no gás de 20 mg L-1, vazão de gás de 0,5 L min-1 e temperatura de 60 °C. Realizou-se por fim uma análise econômica preliminar para fins de comparação entre o processo de sulfitação e ozonização. O processo de ozonização demanda um investimento inicial maior que a sulfitação e à peroxidação. Quando os custos operacionais são comparados verifica-se que o custo operacional para a ozonização é 29% menor que a sulfitação e 43% menor que a peroxidação. Os resultados sugerem a possível aplicação da ozonização como tecnologia alternativa à utilização de enxofre no processo de clarificação. / The sugarcane agroindustry in Brazil currently stands out because it plays a major role in the economy, being responsible for generating jobs, income and products and by-products of interest, such as sugar, ethanol and power. The clarification of sugarcane juice is one of the most critical unit processes in sugar mills. Brazilian sugar is clarified using the sulphitation process. There is a worldwide trend in reducing the use of sulfur compounds in food because of its possible harmful effects on the consumer. In addition, burning elemental sulfur causes serious environmental problems, such as emissions of sulfurous gases, causing acid rain, discommodity in the working environment of plants and corrosion of metals in industrial facilities. Alternative treatments of sugarcane juice, replacing sulfur dioxide have been considered, among them ozonation. The main limitation of ozonation processes is gas-liquid mass transfer. In the present work, ozone mass transfer parameters were evaluated both in water and in model solutions of sucrose containing phenolic compounds present in the sugarcane juice. The main degradation products formed during the process were identified. From these experiments, ozonation of phenolic compounds in solution is characterized by a slow reaction due to the presence of dissolved ozone in the medium. The main intermediates identified were organic acids demonstrating that complete mineralization of the phenolic compounds does not occur. Ozonation experiments with sugarcane juice were carried out following an experimental design aiming at studying color and phenolic compounds removals. After two-hour experiments 80% color removal was achieved ozone concentration of 30 mg L-1, 0.5 L min-1 flow rate and 40 ° C. Moreover, 50% removal of phenolic compounds was achieved for 20 mg L-1 ozone concentration, 0.5 L min-1 flow rate and 60 ° C. The results confirm the efficiency of color removal, main target of the sugar industry. Finally, a preliminary economic analysis was carried out the purpose of comparing the sulphitation and ozonation process, and it was verified that ozonation requires an initial investment greater than sulphitation. Ozonation process requires an initial investment greater than sulphitation and peroxidation. On the other hand, operating costs were compared, the operating cost for ozonation is 29% lower than sulphitation and 43% lower than peroxidation. Results suggest the possible application of ozonation as an alternative technology to the use of sulfur in the clarification process.

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