The study examined the removal mechanism of non-acclimated and acclimated aerobic activated sludge for 29 target organic micropollutants (OMPs) at low concentration. The selection of the target OMPs represents a wide range of physical-chemical properties such as hydrophobicity, charge state as well as a diverse range of classes, including pharmaceuticals, personal care products and household chemicals. The removal mechanisms of OMPs include adsorption, biodegradation, hydrolysis, and vaporization. Adsorption and biodegradation were found to be the main routes for OMPs removal for all target OMPs. Target OMPs responded to the two dominant removal routes in different ways: (1) complete adsorption, (2) strong biodegradation and weak adsorption, (3) medium biodegradation and adsorption, and (4) weak sorption and weak biodegradatio. Kinetic study showed that adsorption of atenolol, mathylparaben and propylparaben well followed first-order model (R2: 0.939 to 0.999) with the rate constants ranging from 0.519-7.092 h-1. For biodegradation kinetics, it was found that benzafibrate, bisphenol A, diclofenac, gemfibrozil, ibuprofen, caffeine and DEET followed zero-order model (K0:1.15E-4 to 0.0142 μg/Lh-1, R2: 0.991 to 0.999), while TCEP, naproxen, dipehydramine, oxybenzone and sulfamethoxazole followed first-order model (K1:1.96E-4 to 0.101 h-1, R2: 0.912 to 0.996). 4 Inhibition by sodium azide (NaN3)and high temperature sterilization was compared, and it was found that high temperature sterilization will damage cells and change the sludge charge state. For the OMPs adaptation removal study, it was found that some of OMPs effluent concentration decreased, which may be due to the slow adaptation of the sludge or the increase of certain bacteria culture; some increased due to chromic toxicity of the chemicals; most of the OMPs had stable effluent concentration trend, it was explained that some of the OMPs were too difficutl to remove while other showed strong quick adaptation. A new module combined of sequencing batch reactor (SBR) and nanofiltration membrane filtration (NF-MBR) was developed to further study the OMPs removal and to exam the concept of compounds (CRT). The NF-MBR was proved to be a promising bioreactor, as OMPs were rejected by NF membrane which leaded to a low OMPs concentration in permeate water, the apparent removal rate was over 80% for most of the OMPs.

Das grundsätzliche Verständnis von Karstgrundwasserleitern ist essentiell für das nachhaltige Management der Rohwasserqualität und letztendlich für sauberes Trinkwasser für bis zu 25 Prozent der Weltbevölkerung. Um dieses Verständnis zu verbessern, wird in der vorliegenden Arbeit das Speicher- und Attenuationspotential eines Karstgrundwasserleiters untersucht. Hierbei werden organische Spurenstoffe als Indikatoren für Transportpfade, Attenuation und Attenuationsprozessen eingesetzt. Als Voraussetzung für die Erfassung belastbarer Daten, wurden geeignete Stabilisierungsstrategien für organische Spurenstoffe in Wasserproben bewertet: Zugabe der Biozide (i) Kupfersulphat und (ii) Natriumazid zu Wasserproben nach der Probenahme und anschließende Lagerung der Proben in flüssiger Form sowie (iii) sofortige Festphasenextraktion (SPE), was zu einer Stabilisierung der Proben durch eine Reduktion des Wassergehaltes führt. Es wurden Fluss- und behandeltes Abwasser untersucht. Diese zeichnen sich üblicherweise durch ein hohes Potential für biologische Aktivität und demnach hohe Biotransformationsraten aus. Analysiert wurde der Einfluss der Lagerungstemperatur von 4 und 28° C für die Proben, die in flüssiger Form gelagert wurden und von 4, 20 und 40° C für die Lagerung der SPE-Kartuschen. Kühlen der Wasserproben allein reichte nicht aus, um die Proben für längere Zeit (> 24 h) zu stabilisieren. Die Zugabe von Kupfersulphat führte zu Problemen mit Azol- und Imidazol-ähnlichen Verbindungen. Natriumazid erwies sich als geeigneter Stabilisierungszusatz. Die besten Ergebnisse konnten für kühl gelagerte SPE-Kartuschen beobachtet werden. Im darauffolgenden Kapitel wird das Langzeitspeicherpotential von Karstgrundwasserleitern untersucht. Um eine nachhaltige Rohwasserqualität zu gewährleisten ist das Verständnis dieses Potentials essentiell. Die Transportdynamik der zwei Herbizide Metazachlor und Atrazin sowie dessen Abbauprodukt (Desethylatrazin) wurde an einer Karstquelle untersucht. Sogar 20 Jahre nach dessen Anwendungsverbot konnten Atrazin und dessen Abbauprodukt nahezu immer im Quellwasser in geringen Konzentrationen (wenige ng L‒1) nachgewiesen werden. Metazachlor dagegen tritt nur nach Niederschlagsereignissen auf und die beobachteten Konzentrationen sind deutlich höher. Ein Vergleich der Dynamik der zwei Herbizide mit der der anorganischen Kationen Ca2+, Mg2+ und der elektrischen Leitfähigkeit zeigte, dass Atrazin mit diesen Parametern korreliert. Aus dieser Beobachtung konnte abgeleitet werden, dass Atrazin innerhalb der Gesteinsmatrix vorliegt und die Rohwasserqualität für Jahrzehnte beeinflusst. Um das in-situ Attenuationspotential innerhalb des Röhrensystems eines Karstgrundwasserleiters zu identifizieren und das Risiko, das von organischen Spurenstoffen ausgeht, abzuschätzen, wurde ein Doppeltracer-Experiment durchgeführt: Der reaktive Stoff Coffein wurde als Markierungsstoff genutzt um das in-situ Attenuationspotential des untersuchten Grundwasserleiters zu bewerten. Aufgrund der niedrigen Bestimmungsgrenze konnten sehr geringe Mengen eingesetzt werden. Um ein Modell zu kalibrieren und die Attenuation des Coffeins zu visualisieren wurde der konservative Markierungsstoff Uranin simultan eingegeben. Diese Methodik wurde in einem gut charakterisierten Karstgrundwasserleiter in Baden-Württemberg getestet. Die Ergebnisse zeigten eine deutlich höhere Attenuationsrate als für einen Karstgrundwasserleiter erwartet wurde. Die Attenuation wurde als Prozess erster Ordnung beschrieben; die bestimmte Halbwertszeit betrug 104 h. Diese geringe Halbwertszeit deutet darauf hin, dass das generell angenommene geringe Attenuationspotential nicht gerechtfertigt ist. Der beobachtete Massenverlust des Coffeins zeigt auf, dass Coffein als reaktiver Markierungsstoff in hydraulisch hochdurchlässigen Systemen, wie Karstgrundwasserleitern, zur Untersuchung des in-situ Attenuationspotentials geeignet ist. Aufgrund der hohen Attenuationsrate des Coffeins, ist nicht mit einer Langzeitkontamination zu rechnen. In der Kombination mit einem konservativen Referenzmarkierungsstoff wird in diesem Kapitel eine ökonomische und ökologisch ungefährliche Methode zur Bestimmung des in-situ Attenuationspotentials vorgestellt. Aufgrund der Ergebnisse des Doppeltracer-Experiments wurde ein Multitracer-Experiment durchgeführt um das ermittelte Attenuationspotential zu verifizieren, dessen Übertragbarkeit auf andere Stoffe zu überprüfen und die Attenuationsprozesse zu spezifizieren. Als Referenzsubstanzen wurden Uranin, Acesulfam und Carbamazepin gemeinsam mit den reaktiven Markierungsstoffen Atenolol, Coffein, Cyclamat, Ibuprofen und Paracetamol in eine Doline eingegeben. Die Durchbruchskurven der reaktiven Markierungsstoffe wurden relativ zu den Referenzsubstanzen ausgewertet. Für keinen der Stoffe konnte eine signifikante Retardation beobachtet werden. Die ermittelten Halbwertszeiten betrugen 38 bis 1400 h (d. h. stabil innerhalb des Beobachtungszeitraums) in der folgenden Reihenfolge (von hoher zu keiner Attenuation absteigend sortiert): Paracetamol > Atenolol ≈ Ibuprofen > Coffein >> Cyclamat. Die Attenuationsraten stimmen generell mit denen aus anderen Studien, die andere Umweltkompartimente untersuchten, und den Ergebnissen des Doppeltracer-Experiments überein. Das Auftreten des Biotransformationsproduktes Atenololsäure diente dem Nachweis von in-situ Biotransformation innerhalb des Karstgrundwasserleitersystems.

De nombreux déchets organiques urbains, industriels et agricoles sont considérés comme des produits résiduaires organiques (PRO). Ils sont potentiellement recyclables en agriculture comme amendement ou fertilisant pour le sol avec selon le type de déchet la mise en œuvre de traitements biologiques (digestion anaérobie, compostage). Du fait de l'utilisation de produits chimiques, les PRO contiennent des micropolluants organiques (µPO) particulièrement quantifiés dans les boues d'épuration. Ces µPO peuvent être toxiques pour les humains et les écosystèmes bien que les concentrations dans les milieux aquatiques soient très faibles (ng-µg.L-1). La plupart de ces µPO ont un fort impact sur l'environnement. Lors des traitements biologiques des boues d'épuration, l'élimination des µPO dépend de deux processus (sorption et biodégradation) eux-mêmes contrôlés par les propriétés physicochimiques de la matière organique et des µPO et les microorganismes présents. La forte sorption et le piégeage des µPO ou leur biodégradation dans la matrice boue lors des traitements minimisent le risque de transfert à l'eau ou à la faune/flore après l'épandage des boues. Cette thèse se propose d'étudier le devenir de différents µPO (hydrocarbures aromatiques polycycliques (HAP), nonylphénols (NP) et produits pharmaceutiques) lors du traitement de boues par digestion anaérobie et compostage en lien avec le devenir de la matière organique et l'affinité des µPO pour certaines fractions de cette matière organique. L'objectif est de mieux comprendre les mécanismes qui régissent l'élimination des µPO et in fine d'estimer comment améliorer le procédé pour limiter les transferts au continuum sol/eau/biote. Dans un premier temps, un protocole de caractérisation de la matière organique a été couplé avec un dosage de µPO au cours d'une incubation anaérobie, sur une matrice modèle (boue) et sur des composés modèles (HAP, NP). Les résultats ont montré que les µPO dissipés se situent dans les compartiments les plus accessibles et les plus dégradables de la matière organique et que cette dissipation est pilotée par la dégradation de la matière ; de plus, un phénomène de vieillissement a été observé pour des molécules dopées. Les résultats démontrent que les µPO étudiés ici ont une affinité pour les matières organiques complexes de type humiques. Lors des incubations, seule la moitié de la matière organique est caractérisée. Le protocole de caractérisation de la matière organique a été modifié pour aller plus loin dans la caractérisation « matière » mais aussi en vue d'une application sur la localisation des µPO tout au long d'un système de traitement comprenant digestion et compostage. Ce protocole a donc été revu afin de pouvoir caractériser des matrices de type lignocellulose. Ce protocole a été appliqué à des échantillons issus de la digestion anaérobie et du compostage de boues en laboratoire. Ces procédés sont capables d'éliminer une partie des µPO ; le couplage des deux augmentant le taux d'élimination. L'évolution des fractions matière reflètent la dégradation de la matière organique lors des traitements. De plus, le devenir des µPO étudiés est piloté par le devenir de la matière organique nous permettant de proposer des stratégies d'optimisation de leur dissipation.Les résultats acquis permettent de déterminer des taux d'abattement des µPO lors des traitements des boues mais aucune information n'est donnée quant aux mécanismes précis d'élimination. Les mêmes traitements ont été menés en utilisant des molécules marquées au 14C. Les résultats obtenus sur trois molécules (fluoranthène, NP et sulfaméthoxazole) montrent que les µPO ne sont pas minéralisés lors de la digestion anaérobie. Lors du compostage des boues digérées, une minéralisation du NP apparaît lors de la phase de maturation. Diverses hypothèses peuvent alors expliquer l'élimination constatée au cours des traitements sans molécule marquée : métabolites ou résidus non extractibles sont formés. / Animal manures, urban organic wastes including sewage sludge, food processing and other industrial wastes are considered as organic wastes that are potentially recycled in agriculture as soil amendment or fertilizer after biological treatment like anaerobic digestion and composting.Due to the use of chemicals and industrial activities, these organic wastes contain organic micropollutants, particularly quantified in sewage sludge. These micropollutants are a family of organic compounds which may be toxic for humans or ecosystems even though their concentrations in aquatic environments are usually low (µg to ng.L-1). Most of them have huge impacts on environment (e.g. some of them are endocrine disruptors that can feminize fishes in rivers with concentrations of few ng.L-1).During biological treatments of sewage sludge, micropollutants elimination depends on two processes (sorption and biodegradation) that are driven by physicochemical properties of organic matter and micropollutants and microorganisms. Strong sorption and trapping of organic micropollutants or their biodegradation in sludge matric during anaerobic digestion and composting can minimize their transfer into water or biota after spreading.This thesis aims at studying the fate of organic micropollutants (polycyclic aromatic hydrocarbons (PAHs), nonylphenols (NPs) and pharmaceuticals compounds) during sludge treatment by anaerobic digestion and composting in link with the fate of organic matter and the micropollutants affinity for some organic matter fractions. The objective is to better understand the mechanisms which control the micropollutants elimination and estimate how to improve the process to minimize environmental impact.First, a method for sludge organic matter characterization is coupled to organic micropollutants quantification during a model batch process (anaerobic incubation), on a model matrix (sludge) and model compounds (PAHs, NPs). Results show that dissipated micropollutants are located in more accessible and degradable fraction of organic matter and that dissipation is driven by organic matter degradation; furthermore, ageing phenomenon is observed for spiked compounds. Results show that micropollutants have strong affinity for complex organic matter (humic-like substances).During incubations, the quantity of characterized organic matter corresponds only to 50 % of chemical oxygen demand. A modified protocol for characterizing organic matter is set up to go further on organic matter characterization but also to apply it to localization of organic micropollutants. This protocol is also modified in order to characterize other organic matrices (compost).The new protocol is applied to samples from anaerobic digestion and composting of sludge at lab-scale. Anaerobic digestion and composting are able to eliminate organic micropollutants. Coupling both processes increases micropollutants removal. The fate of organic matter pools during processes mimics the fate of organic matter. A link between the fate of organic matter and the fate of organic micropollutants is determined during anaerobic digestion and composting.The results allow determining organic micropollutants removal during anaerobic digestion and composting of sludge but no information is given about the removal mechanisms. Anaerobic digestion with composting is set up at lab-scale with the use of organic 14C labelled micropollutants. The results with three molecules (fluoranthene, sulfamethoxazole, nonylphenols) show that organic micropollutants are not mineralized during anaerobic digestion. During composting, only nonylphenols are mineralized during the maturation phase. Hypothesis about micropollutants removal are the production of metabolites or the formation of non-extractable residues.

Abstract: The worldwide consumption of pharmaceuticals and personal care products for healthcare purposes has resulted in the occurrence of organic micropollutants (OMPs) in freshwater and wastewater resources. These pollutants are not entirely removed by conventional water and wastewater treatment plants, leading to potential human and animal health problems. Membranes are a promising technology capable of solving this problem. This study evaluated the ability of high-pressure driven membranes such as nanofiltration (NF) and reverse osmosis (RO) to remove OMPs. A total of 13 compounds were selected so that a broad range of molecular weights and octanol-water partition coefficients (log Kow) could be studied. Three commercial thin-film-composite polyamide membranes (NF1, NF6, and RO4) were tested. Filtration experiments were conducted using a cross-flow membrane system at pH 6 8 and 10. The membranes were characterized by atomic force microscopy and scanning electron microscopy that allowed a more profound understanding of the membrane surface structures. Experimental results showed that the permeate flux of NF6 is dependent on the pH of the feed solution. An increase in the feed pH from 6 to 10 resulted in an increase on the permeate flux from 14.5 to 24 L m-2 h-1 bar-1, which caused a drop in the rejection of some OMPs by NF6. Nevertheless, for most OMPs, as pH increased to 10, rejection increased for NF1 and RO4 due to electrostatic repulsion between the negatively charged membrane surface and the ionized OMPs. It was observed that ionic hydrophobic compounds could be highly rejected (> 95%) by NF1 and RO4. The study indicated that the rejection of non-ionic hydrophilic and hydrophobic OMPs were rejected effectively by RO4 (> 90%), and the rejection was mostly dominated by size exclusion and hydrophobic interactions between the membrane and the OMPs. Furthermore, the study revealed that the properties of the compounds, the intrinsic properties of the membrane, and the operating conditions have a significant influence on the rejection of OMPs.

Les activités anthropiques génèrent une contamination à de faibles doses des boues de station d'épuration par des micropolluants organiques persistants tels que les hydrocarbures aromatiques polycycliques (HAP), les polychlorobiphényles et le nonylphénol. Cette étude porte sur la détermination de l'influence des microorganismes au cours de la méthanisation sur le devenir de ces trois familles de micropolluants. Un protocole spécifique a été mis au point pour extraire des microorganismes de leur écosystème d'origine tout en conservant la singularité structurelle et fonctionnelle des communautés. Trois communautés, au passif de pollution différent, ont ainsi été soumises à la même pression de sélection (substrat et disponibilité en micropolluant) dans des bioréacteurs continus de méthanisation. Ces trois écosystèmes se sont alors distingués parfaitement via les caractéristiques de leurs communautés et la réalisation de fonctions diverses de digestion. Or, la dégradation des micropolluants a convergé dans ces 3 systèmes, démontrant l'absence de lien direct entre méthanogenèse et dégradation de ces molécules et une absence de spécialisation des communautés pour cette dégradation. En outre, il a été observé que la répartition des micropolluants au sein de la boue est influencée par les voies métaboliques des communautés. Plus le degré de digestion est avancé, plus les micropolluants sont abondants dans le compartiment aqueux et sorbés à la matière dissoute et colloïdale. Des fonctions, spécifiques de la dégradation des micropolluants, ont été étudiées (i) en suivant l'assimilation de phénanthrène marqué au 13C en culture batch, source principale de carbone, ce qui n'a pas permis d'observer sa minéralisation et (ii) en recherchant la présence de gènes fonctionnels ce qui n'a pas permis la détection des fonctions ciblée. Des activités œstrogéniques, androgéniques, dioxin-like et HAP-like, l'activité HAP-like est la plus exprimée dans les réacteurs à l'équilibre. Le degré de digestion, via une modification de la répartition des HAP, explique l'augmentation de l'activité HAP-like dans le compartiment aqueux des boues les plus digérées (et sa diminution dans le compartiment particulaire). L'activité HAP-like n'est pas entièrement expliquée par le dosage des HAP, ce qui suggère la présence d'intermédiaires métaboliques ayant une activité biologique et dont la nature différerait suivant le métabolisme exprimé par les communautés microbiennes. / Due to anthropogenic activity the sludge of wastewater treatment plants are contaminated by organic micropollutants like polycyclic aromatic hydrocarbons (PAH), polychlorinated biphenyls and nonylphenol. This study focuses on the influence of microbial communities on the fate of these three micropollutant families during the anaerobic digestion process. A specific protocol was developed to extract microorganisms from their native ecosystem while maintaining their structural and functional singularity. Three communities, with different pollution history, were thus extracted and subjected to the same selection pressure (availability of substrate and micropollutant) in continuous anaerobic digesters. These three ecosystems can be perfectly identified through the characteristics of their microbial communities and their global metabolism. However, our results show also that the degradation of micropollutant converged in these 3 systems, demonstrating no direct link between methanogenesis and micropollutant degradation and no specialization of the microbial communities toward this degradation. In addition, the distribution of micropollutants in sludge is influenced by the metabolic pathways of those communities. The more the digestion is advanced, the greater the micropollutants are abundant in the aqueous compartment and adsorbed to the dissolved and colloidal matter. Specific functions for micropollutant degradation were studied (i) by following the 13C-labeled phenanthrene assimilation as main carbon source, which did not allow observing its mineralization and (ii) by exploring the presence of functional genes, which did not allow the detection of the targeted functions. Among the estrogenic, androgenic, dioxin-like and PAH-like activities, PAH-like activity is more expressed in all reactors at the steady state. The different degrees of digestion, through a change in PAH distribution, explain the increase in PAH-like activity in the aqueous compartment of the most digested sludge (and its decrease in the particulate compartment). PAH-like activity is not fully explained by PAH quantification, suggesting the presence of by-products with biological activity and which could be different depending on the metabolic pathway of the microbial communities.

A range of chemical pollutants now contaminate drinking water sources and present a public health concern, including organic compounds, such as pharmaceuticals and pesticides, and both metalloids and heavy metals, such as arsenic and lead. Metalloids and heavy metals have been detected in private drinking water wells, which do not fall under federal drinking water regulations, as well as in urban tap water, due to the introduction of contamination to the drinking water distribution system. Further, many so-called “emerging organic contaminants,” which are present in drinking water sources at detectable levels but have unknown long-term health implications, do not fall under federal drinking water regulations. To protect the health of consumers, drinking water treatment at the point-of-use (POU) (i.e., the tap) is essential. Next-generation POU treatment technologies must require minimal energy inputs, be simple enough to permit broad application among different users, and be easily adaptable for removal of a wide range of pollutants. Nanomaterials, such as carbon nanotubes and iron oxide nanoparticles, are ideal candidates for next-generation drinking water treatment, as they exhibit unique, high reactivity and necessitate small treatment units. However, concerns regarding water pressure requirements and nanomaterial release into the treated supply limit their application in traditional reactor designs. To bridge the gap between potential and practical application of nanomaterials, this study utilizes electrospinning to fabricate composite nanofiber filters that effectively deploy nanomaterials in drinking water treatment. In electrospinning, a high voltage draws a polymer precursor solution (which can contain nanomaterial additives, in the case of nanocomposites) from a needle to deposit a non-woven nanofiber filter on a collector surface. Using electrospinning, we develop an optimized, macroporous carbon nanotube-carbon nanofiber composite that utilizes the sorption capacity of embedded carbon nanotubes, and achieves a key balance between material strength and reactivity towards organic pollutants. Additionally, via single-pot syntheses, we develop two optimized polymer-iron oxide composites for removal of heavy metal contamination by inclusion of iron oxide nanoparticles and either cationic or anionic surfactants in the electrospinning precursor solution. In hybrid materials that contain a well-retained quaternary ammonium surfactant (tetrabutylammonium bromide) and iron oxide nanoparticles, ion exchange sites and iron oxide sites are selective for chromate and arsenate removal, respectively. We demonstrated that a sulfonate surfactant, sodium dodecyl sulfate, acted as a removable porogen and an agent for surface segregation of iron oxide nanoparticles, thus enhancing composite performance for removal of lead, copper, and cadmium. Notably, nanoparticles embedded in composites exhibited comparable activity to freely dispersed nanoparticles. Collectively, the composites developed in this work represent a substantial advance towards the overlap of effective nanomaterial immobilization and utilization of nanomaterial reactivity. Outcomes of this work advance current knowledge of nanocomposite fabrication, and contribute to the responsible and effective deployment of nanomaterials in POU drinking water treatment.

Les micropolluants organiques (MPO) tels que les HAPs, PCBs et NP sont sous la surveillance étroite des différentes agences de santé et de l'environnement à cause de leurs effets toxiques, cancérigènes et perturbateurs endocriniens sur les organismes vivants. Dans l'environnement, ils se retrouvent dans le sol, les aquifères, les eaux usées, et en raison de leurs propriétés hydrophobes, ces MPO sont principalement associés aux compartiments matière organique dans les boues d'épuration et les sédiments de rivières. La digestion anaérobie, procédé de stabilisation des boues, présente un potentiel pour l'abattement de ces composés. Les deux principaux mécanismes qui régissent l'abattement dans ces conditions des MPO sont le cométabolisme et la biodisponibilité. Leur double influence est évaluée dans ce travail, avec un focus fort sur l'étude des interactions MPO-matrice, la détermination de la distribution des MPO dans les compartiments physiques de la matrice (libre, sorbé à la matière dissoute et colloïdale (DCM) et sorbé aux particules) et avec une caractérisation fonctionnelle, physique et chimique détaillée de la matrice. Pour cela, des réacteurs anaérobies continus et batch ont été mis en œuvre avec des boues de caractéristiques différentes. L'abattement des MPO varie considérablement en fonction des caractéristiques des boues s'expliquant soit par des variations du niveau de cométabolisme, soit par les différents niveaux de biodisponibilité ; ceci suggère qu'une caractérisation détaillée de la matrice boue pourrait aider à prévoir les niveaux d'abattement des MPO. Par ailleurs, les cinétiques en batch montrent que l'abattement des MPO est associé aux premières étapes de la digestion anaérobie, conjointement à leur transfert du compartiment des particules vers le compartiment aqueux. L'abattement des MPO s'observe simultanément dans les trois compartiments libre, sorbé à la DCM et sorbé aux particules. Il est aussi noté l'importance du compartiment DCM sur l'abattement des MPO de haut poids moléculaire. Les coefficients de partage KDOC et Kpart ont été calculés pour étudier les interactions MPO-matrice., Ces données couplées à celles de caractérisation fonctionnelle de la matrice par fluorescence 3D ont permis de construire un modèle explicatif et prédictif des interactions MPO-matrice à l'aide de la méthode de régression partielle des moindres carrés (PLS). Il a été constaté que le compartiment type acide humique a un rôle important dans les interactions MPO-matrice, principalement dans la phase aqueuse, et dans la phase particulaire, les protéines complexes régissent les interactions. Enfin, des modèles PLS explicatifs et prédictifs d'abattement total des MPO ont été construits. Il en ressort que l'abattement des MPO est favorisé par tous les paramètres du cométabolisme (abattement des divers compartiments matière) et par la concentration des MPO en phase aqueuse ce qui tenterait à confirmer que ce compartiment correspond au compartiment biodisponible. Le modèle prédictif basé sur les caractéristiques des boues initiales a identifié les concentrations initiales de MPO (libre, sorbé à la DCM et aux particules) comme les variables les plus importantes qui permettent de prédire l'abattement total des MPO. Cette étude contribue ainsi à mieux comprendre la répartition des MPO dans les matrices boue, et son implication dans le devenir des MPO, de prévoir cette répartition par une caractérisation fonctionnelle de la matrice et de proposer des stratégies pour optimiser l'abattement des MPO au cours de la digestion anaérobie. / Organic micropollutants (OPs) such as PAHs, NP and PCBs, are nowadays looked as environmental pollutants by environmental and health agencies because of their toxic, carcinogenic and endocrine disrupting effect on living organisms. Within the environment, they can deposit to soil, water bodies and sewage system and due to their hydrophobic properties, they are mainly associated with hydrophobic compartments such as organic matter in sewage sludge. Anaerobic digestion has been shown as a potential biological process for removing these compounds. The two main mechanisms that govern their anaerobic removals are the cometabolism and the bioavailability. In this work, cometabolism and bioavailability influences were evaluated focusing mainly on the study of the OP-organic matrix interactions, the determination of the OPs distribution among the physical compartments (free, sorbed to dissolved and colloidal matter (DCM) and sorbed to particles) combined with a detailed physical, chemical and functional matrix characterization. For this, continuous and batch anaerobic reactors were fed with different sludge samples. It was found that the OPs removals varied greatly as a function of sludge characteristics and that greater or lesser removal might be explained either by variations in cometabolism or by different levels of bioavailability, suggesting that a detailed characterization of the feed may help to predict the OPs removals. Additionally, batch kinetics demonstrated that OPs removals are coupled to the first step of the anaerobic digestion, jointly to the OPs transfer from the particules to the aqueous compartment. The OPs are simultaneously removed from the three physical compartments (free, DCM and particules). Moreover, it was highlighted the importance of the DCM fraction on the removal of the high molecular weight OPs. KDOC and Kpart partition coefficients were calculated to study the OP-organic matrix interactions coupled to a functional characterization by 3D fluorescence of the matrix in order to construct an explicative and predictive model of the OP-organic matrix interactions using partial least square regression (PLS). It was found that the humic acid-like compartment has a great role in the OP-organic matrix interactions mainly in the aqueous phase, and in the particulate phase, the complex proteins govern the interactions. Finally, explanatory and predictive PLS models of total OPs removals were constructed. It was concluded that OPs removals are favored by all cometabolic parameters (substrates removals) jointly to the aqueous OPs concentration which tends to confirm that this compartment corresponds to the bioavailable one. The predictive model based on the initial sludge characteristics, identified the initial OPs concentrations (free, DCM and particulate) as the most important variables that predict the total OPs removals. This study contributes to better understand the OPs distribution among the sludge compartments and its role in the fate and removal of the compounds, to predict this distribution through matter functional characterization and to propose strategies in order to optimize the OPs removals under anaerobic conditions.

Constructed wetlands (CW) and soil aquifer treatment (SAT) represent natural wastewater treatment systems (NWTSs). The high costs of conventional wastewater treatment techniques encourage more studies to investigate lower cost treatment methods which make these appropriate for developing and also in developed countries. The main objective of this research was to investigate the removals of nutrients and organic micropollutants (OMPs) through SAT, CW and the CW-SAT hybrid system. CWs are an efficient technology to purify and remove different nutrients as well as OMPs from wastewater. They removed most of the dissolved organic matter (DOC), total nitrogen (TN), ammonium and phosphate. Furthermore, CWs aeration could be used as one of the alternatives to reduce CWs footprint by around 10%. The vegetation in CWs plays an essential role in the treatment especially for nitrogen and phosphate removals, it is responsible for the removal of 15%, 55%, 38%, and 22% for TN, dissolved organic nitrogen (DON), nitrate and phosphate, respectively. CWs achieved a very high removal for some OMPs; they attenuated acetaminophen, caffeine, fluoxetine and trimethoprim (>90%) under different redox conditions. Moreover, it was found that increasing temperature (up to 36 C) could enhance the removals of atenolol, caffeine, DEET and trimethoprim by 17%, 14%, 28% and 45%, respectively. On the other hand, some OMPs, were found to be removed by vegetation such as: acetaminophen, caffeine, fluoxetine, sulfamethoxazole, and trimethoprim. Moreover, atenolol, caffeine, fluoxetine and trimethoprim, showed high removal (>80%) through SAT system. It was also found that, temperature increasing and using primary instead of secondary effluent could enhance the removal of some OMPs. The CWs performance study showed that these systems are adapted to the prevailing extreme arid conditions and the average percent removals are about, 88%, 96%, 98%, 98% and 92%, for COD, BOD and TSS, ammonium and phosphate, respectively. Additionally, the natural hybrid system (CW-SAT) can provide an effective treatment technology of reclaimed water for replenishing aquifers and subsequent reuse. This hybrid system embodied the performance advantages of both processes and exhibits a high potential for removal of OMPs, nutrients, metals as well as pathogens, bacteria and viruses.

The current global water crisis in addition to continues contamination of natural water bodies with harmful organic micropollutants (OMPs) have driven the development of new water treatment technologies that allow the efficient removal of such compounds. Among a long list of OMPs, antibiotics are considered as top priority pollutants to be treated due to their great resistance to biological treatments and their potential to develop bacterial resistance. Different approaches, such as membrane-based and advance oxidation processes have been proposed to alleviate or minimize antibiotics discharge into aquatic environments. However most of these processes are costly and generate either matrices with high concentration of OMPs or intermediate products with potentially greater toxicity or persistence. Therefore, this thesis proposes the study of an anaerobic membrane bioreactor (AnMBR) for the treatment of synthetic municipal wastewater containing sulfamethoxazole (SMX), a world widely used antibiotic. Besides the general evaluation of AnMBR performance in the COD removal and biogas production, this research mainly focuses on the SMX removal and its degradation pathway. Thus 5 SMX quantification was performed through solid phase extraction-liquid chromatography/mass spectrometry and the identification of its transformation products (TPs) was assessed by gas chromatography/mass spectrometry technique. The results achieved showed that, working under optimal conditions (35°C, pH 7 and ORP around -380 to -420 mV) and after a biomass adaptation period (maintaining 0.85 VSS/TSS ratio), the AnMBR process provided over 95% COD removal and 95-98% SMX removal, while allowing stable biogas composition and methane production (≈130 mL CH4/g CODremoved). Kinetic analysis through a batch test showed that after 24 h of biological reaction, AnMBR process achieved around 94% SMX removal, indicating a first order kinetic reaction with K= 0.119, which highlights the high degradation capacity of the anaerobic bacteria. Along the AnMBR process, 7 TPs were identified and possible degradation pathways were proposed. At low influent SMX concentrations (<10ppb), the only TPs detected was (1) Benzene sulfonamide N-Butyl. However, as the influent SMX concentration increased, it was possible to identify (2) Sulfanilamide, (3) Sulfisomidine and (4) 4-Aminothiophenol. Further degradation of compounds 2, 3 and 4 were detected after 9 hours of biological reaction in a batch test, producing three new intermediate products: (5) Aniline, (6) 4-Pyrimidinamine, 2,6-dimethyl and (7) Acetamide, N-(4-mercaptophenyl). Most of the detected TPs present a less complex structure than SMX, which can be associates with a lower toxicity.

<p>Human activities represent a significant burden on the global water cycle, with large and increasing demands placed on limited water resources by manufacturing, energy production and domestic water use. In addition to changing the quantity of available water resources, human activities lead to changes in water quality by introducing a large and often poorly-characterized array of chemical pollutants, which may negatively impact biodiversity in aquatic ecosystems, leading to impairment of valuable ecosystem functions and services. Domestic and industrial wastewaters represent a significant source of pollution to the aquatic environment due to inadequate or incomplete removal of chemicals introduced into waters by human activities. Currently, incomplete chemical characterization of treated wastewaters limits comprehensive risk assessment of this ubiquitous impact to water. In particular, a significant fraction of the organic chemical composition of treated industrial and domestic wastewaters remains uncharacterized at the molecular level. Efforts aimed at reducing the impacts of water pollution on aquatic ecosystems critically require knowledge of the composition of wastewaters to develop interventions capable of protecting our precious natural water resources.</p><p>The goal of this dissertation was to develop a robust, extensible and high-throughput framework for the comprehensive characterization of organic micropollutants in wastewaters by high-resolution accurate-mass mass spectrometry. High-resolution mass spectrometry provides the most powerful analytical technique available for assessing the occurrence and fate of organic pollutants in the water cycle. However, significant limitations in data processing, analysis and interpretation have limited this technique in achieving comprehensive characterization of organic pollutants occurring in natural and built environments. My work aimed to address these challenges by development of automated workflows for the structural characterization of organic pollutants in wastewater and wastewater impacted environments by high-resolution mass spectrometry, and to apply these methods in combination with novel data handling routines to conduct detailed fate studies of wastewater-derived organic micropollutants in the aquatic environment. </p><p>In Chapter 2, chemoinformatic tools were implemented along with novel non-targeted mass spectrometric analytical methods to characterize, map, and explore an environmentally-relevant “chemical space” in municipal wastewater. This was accomplished by characterizing the molecular composition of known wastewater-derived organic pollutants and substances that are prioritized as potential wastewater contaminants, using these databases to evaluate the pollutant-likeness of structures postulated for unknown organic compounds that I detected in wastewater extracts using high-resolution mass spectrometry approaches. Results showed that application of multiple computational mass spectrometric tools to structural elucidation of unknown organic pollutants arising in wastewaters improved the efficiency and veracity of screening approaches based on high-resolution mass spectrometry. Furthermore, structural similarity searching was essential for prioritizing substances sharing structural features with known organic pollutants or industrial and consumer chemicals that could enter the environment through use or disposal.</p><p>I then applied this comprehensive methodological and computational non-targeted analysis workflow to micropollutant fate analysis in domestic wastewaters (Chapter 3), surface waters impacted by water reuse activities (Chapter 4) and effluents of wastewater treatment facilities receiving wastewater from oil and gas extraction activities (Chapter 5). In Chapter 3, I showed that application of chemometric tools aided in the prioritization of non-targeted compounds arising at various stages of conventional wastewater treatment by partitioning high dimensional data into rational chemical categories based on knowledge of organic chemical fate processes, resulting in the classification of organic micropollutants based on their occurrence and/or removal during treatment. Similarly, in Chapter 4, high-resolution sampling and broad-spectrum targeted and non-targeted chemical analysis were applied to assess the occurrence and fate of organic micropollutants in a water reuse application, wherein reclaimed wastewater was applied for irrigation of turf grass. Results showed that organic micropollutant composition of surface waters receiving runoff from wastewater irrigated areas appeared to be minimally impacted by wastewater-derived organic micropollutants. Finally, Chapter 5 presents results of the comprehensive organic chemical composition of oil and gas wastewaters treated for surface water discharge. Concurrent analysis of effluent samples by complementary, broad-spectrum analytical techniques, revealed that low-levels of hydrophobic organic contaminants, but elevated concentrations of polymeric surfactants, which may effect the fate and analysis of contaminants of concern in oil and gas wastewaters. </p><p>Taken together, my work represents significant progress in the characterization of polar organic chemical pollutants associated with wastewater-impacted environments by high-resolution mass spectrometry. Application of these comprehensive methods to examine micropollutant fate processes in wastewater treatment systems, water reuse environments, and water applications in oil/gas exploration yielded new insights into the factors that influence transport, transformation, and persistence of organic micropollutants in these systems across an unprecedented breadth of chemical space.</p> / Dissertation