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Over the past decade, the objectives for coagulation based drinking water treatment processes have changed significantly. These changes are a result of stringent goals related to natural organic matter (NOM) removal to mitigate the formation of subsequent harmful and health-related disinfection by-products (DBPs) and the need to achieve adequate filtration performance to ensure sufficient particle removal for pathogen control. Another concern associated with coagulation optimization is the potential unintended consequences of a coagulant change on the distribution system, specifically related to lead release from lead pipe and solder materials. Optimizing these multi-objectives in a direct filtration treatment process presents significant challenges for source waters characterized by low levels of turbidity, alkalinity and organic matter content. Bench and pilot-scale experiments were conducted to evaluate the performance of ferric sulfate, polyaluminum chloride (PACl) and aluminum chlorohydrate (ACH) against aluminum sulfate (alum) using variable coagulation dosage and pH conditions for a direct filtration facility. Bench-scale experiments were conducted to optimize NOM removal during coagulation using traditional organic matter surrogates coupled with molecular size characterization techniques. Pilot-scale studies provided a snapshot of feasibility in terms of filtration performance for favourable bench-scale conditions and also identified optimal conditions for filtration performance. Results from pilot testing demonstrated that favourable conditions identified for increased potential NOM removals during bench-scale testing were significantly different than optimal filtration conditions identified during pilot studies; and, in fact, severely compromised direct filtration performance due to increased solids loading to the filters. Bench-scale experiments evaluated lead leaching from lead and lead:tin solder galvanically connected to copper under stagnant conditions using variable chloride-to-sulfate mass ratio (CSMR) conditions for alum, ferric sulfate and PACl. Although recent research identifies high CSMRs (>0.5) as the main mechanism of attack in distribution systems following coagulant changeovers, CSMR was not the primary catalyst for lead leaching following the coagulant changeover conditions evaluated in this study. Residual concentrations of iron and aluminum remaining following coagulation were the principal contributors. Positive correlations were revealed between particulate iron and particulate lead concentrations following stagnation demonstrating that the adsorption of lead to iron oxides is a viable hypothesis for lead release.

Solid wastes containing sulfate, such as construction and demolition debris (CDD), are an important source of pollution, which can create a lot of environmental problems. It is suggested that these wastes have to be separated from other wastes, especially organic waste, and place it in a specific area of the landfill. This results in the rapid rise of the disposal costs of these gypsum wastes. Although these wastes can be reused as soil amendment or to make building materials, a concern has been raised by regulators regarding the chemical characteristics of the material and the potential risks to human health and the environment due to CDD containing heavy metals and a high sulfate content. Soils containing gypsum, namely gypsiferous soils, also have several problems during agricultural development such as low water retention capacity, shallow depth to a hardpan and vertical crusting. In some mining areas, gypsiferous soil problems occur, coupled with acid mine drainage (AMD) problems which cause a significant environmental threat. Reduction of the sulfate content of these wastes and soils is an option to overcome the above mentioned problems. This study aimed to develop sulfate removal systems to reduce the sulfate content of CDD and gypsiferous soils in order to decrease the amount of solid wastes as well as to improve the quality of wastes and soils for recycling purposes or agricultural applications. The treatment concept leaches the gypsum contained in the CDD by water in a leaching step. The sulfate containing leachate is further treated in biotic or abiotic systems. Biological sulfate reduction systems used in this research were the Upflow Anaerobic Sludge Blanket (UASB) reactor, Inverse Fluidized Bed (IFB) Reactor and Gas Lift Anaerobic Membrane Bioreactor (GL-AnMBR). The highest sulfate removal efficiency achieved from these three systems ranges from 75 to 95%. The treated water from the bioreactor can then be reused in the leaching column. Chemical sulfate removal (abiotic system) is an alternative option to treat the CDD leachate. Several chemicals were tested including barium chloride, lead(II) nitrate, calcium chloride, calcium carbonate, calcium oxide, aluminium oxide and iron oxide coated sand. A sulfate removal efficiency of 99.9% was achieved with barium chloride and lead(II) nitrate.For AMD and gypsiferous soils treatment, five types of organic substrate including bamboo chips (BC), municipal wastewater treatment sludge (MWTS), rice husk (RH), coconut husk chip (CHC) and pig farm wastewater treatment sludge (PWTS) were tested as electron donors for biological sulfate reduction treating AMD. The highest sulfate reduction efficiency (84%) was achieved when using the combination of PWTS, RH and CHC as electron donors. Then, this organic mixture was further used for treatment of the gypsiferous soils. The gypsum mine soil (overburden) was mixed with an organic mixture in different amounts including 10, 20, 30 and 40% of soil. The highest sulfate removal efficiency of 59% was achieved in the soil mixture which contained 40% organic material.The removal of sulfide from the effluent of the biological sulfate reduction process is required as sulfide can cause several environmental impacts or be re-oxidized to sulfate if directly discharged to the environment. Electrochemical treatment is one of the alternatives for sulfur recovery from aqueous sulfide. A non-catalyzed graphite electrode was tested as electrode for the electrochemical sulfide oxidation. A high surface area of the graphite electrode is required in order to have less internal resistance as much as possible. The highest sulfide oxidation rate was achieved when using the external resistance at 30 Ω at a sulfide concentration of 250 mg L-1

Les homéoprotéines sont des facteurs de transcription importants au cours du développement des organismes vivants, capables notamment de voyager de cellule en cellule. Ces protéines comportent une longue extrémité N-terminale désordonnée, suivie de trois hélices α séparées par une boucle et un tour. Des études de relations structure-activité ont montré que des domaines cationiques (riches en K et R) particuliers dans ces protéines sont responsables de ces propriétés de transfert cellulaire leur permettant d’être secrétées et internalisées dans les cellules. Ces processus impliquent que ces protéines hydrophiles soient capables de franchir la membrane plasmique composée d'un coeur hydrophobe. La membrane plasmique est en effet composée d’une bicouche lipidique, dans laquelle sont insérées de nombreuses protéines, telles que les protéoglycanes portant des ramifications de glycosaminoglycanes (GAG), polysaccharides anioniques. Dans le but de comprendre au niveau moléculaire le processus d'entrée des homéoprotéines dans des cellules eucaryotes, différentes constructions protéiques ont été produites et étudiées : le peptide pénétrant les cellules correspondant à l'hélice 3 (H3), la séquence correspondant à l'homéodomaine (HD), l'homéodomaine étendu d'une séquence putative de liaison aux GAG (NLS-HD) et la protéine entière (En2). La quantification absolue de l’entrée de ces constructions dans des cellules CHO-K1 par spectrométrie de masse a mis en évidence une efficacité d'entrée meilleure pour H3 > NLS-HD > HD, ainsi que l’importance des GAG de surface dans le processus et plus particulièrement celui des héparanes sulfates (HS). Des expériences complémentaires d’ITC, de dichroïsme circulaire et de RMN ont permis d'identifier deux sites d’interaction avec l’héparine (un site principal de haute affinité et un site secondaire de plus basse affinité), interagissant principalement avec le polysaccharide par interactions électrostatiques. In fine, ces études conduisent à une meilleure compréhension moléculaire du processus d'internalisation des homéoprotéines dans des cellules eucaryotes. / Homeoproteins are important transcription factors during the development of living organisms, and are able to travel from cell to cell. These proteins contain a long N-terminal extremity structurally disordered, followed by three α helices separated by a U-turn. Structure-activity relation studies have shown that in these proteins, some cationic domains (rich in K and R) confer them the cellular transfer properties, allowing them to be secreted by and internalized into cells. These processes imply that the hydrophilic proteins are able to cross plasma membrane. Indeed, the plasma membrane possess a hydrophobic heart and is composed by a lipidic bilayer, in which numerous proteins are inserted, such as proteoglycans carrying glycosaminoglycan (GAG) ramifications, that belong to anionic polysaccharids. In order to understand the entry process of homeoproteins into eukaryotic cells at a molecular level, different proteic constructions have been produced and studied: the cell penetrating peptide corresponding to the third α helix (H3), the sequence corresponding to its homeodomain (HD), the homeodomain with an added putative GAG-binding domain (NLS-HD), and the wild-type protein Engrailed 2 (En2). The absolute mass spectrometry quantification of the peptide and proteins in cells shows a range of internalization efficiency as follows: H3 > NLS - HD > HD. It also highlights the importance of cell-surface GAGs in the internalization and more particularly that of heparan sulfates (HS). Complementary experiments of ITC, circular dichroism and NMR have shown two interaction sites for the heparin (one principal site of high affinity and a secondary site showing a lower affinity) both interacting mainly with polysaccharidic residues using electrostatic interactions. In fine, these studies lead to a better molecular understanding of homeoproteins internalization process in eukaryotic cells.

Ce travail de thèse a eu pour thème principal le protéoglycane syndecan-1 au cours du myélome multiple, une hémopathie maligne caractérisée par la présence d'un clone de plasmocytes tumoraux au sein de la moelle osseuse. Syndecan-1 est un élément majeur de la physiopathologie du myélome multiple, ce protéoglycane étant au coeur d'un réseau complexe d'interactions moléculaires conditionnant le devenir des cellules plasmocytaires tumorales.Les chaînes de glycosaminoglycanes présentes sur le core protéique de syndecan-1sont responsables d'une grande partie de son activité. Nous avons ainsi caractérisé, par une approche transcriptomique, 100 gènes codant les protéines impliquées dans la synthèse et la modification de ces chaînes. Nous avons de cette manière identifié des cibles moléculairesen vue de moduler, voire d'inhiber leur activité.Dans le but d'identifier les métalloprotéinases des familles ADAM et ADAMTS susceptibles d'interagir avec syndecan-1, nous avons réalisé l'étude du profil d'expression des gènes codant ces reprolysines et leurs inhibiteurs dans les cellules de la différentiation lymphocytaire B, les cellules plasmocytaires normales et tumorales ainsi que dans l'environnement médullaire.Dans une dernière partie, nous avons évalué l'efficacité d'une approche d'inhibitiondes chaînes héparanes sulfates via l'utilisation de l'héparine. Nous observons que certaines lignées myélomateuses sont inhibées par l'héparine et ses dérivés et que ces mêmes lignées sont stimulées par l'antidote de l'héparine, le sulfate de protamine. Les mécanismes mis enjeu sont en relation avec la modulation de la biodisponibilité des facteurs permettant la croissance des cellules. / Multiple myeloma is a hematological malignancy characterized by the expansion of aclone of malignant plasma cells in the bone marrow compartment. Syndecan-1 is a majorproteoglycan involved in a complex network of molecular interactions in multiple myelomaphysiopathology. As heparan sulfate and chondroitin sulfate chains are the bioactive components ofsyndecan-1, we first analysed the signature of genes encoding 100 proteins involved in thesynthesis of these chains, from precursor uptake to post-translational modifications, usingAffymetrix microarrays.In order to identify the metalloproteinases belonging to ADAM and ADAMTS familiespotentially implicated in the interactions with syndecan-1, we performed a gene expressionprofile focused on the genes encoding these reprolysines and their inhibitors.In a last part, we evaluated the efficacy of an inhibitory approach based on theutilization of heparin in human myeloma cell lines in vitro, inhibitory effects being in relationwith a modulation of the biodisponibility of heparin-binding factors.This work led us to identify targets of interest in relation with syndecan-1 biology inmultiple myeloma. They could be used to design new therapeutic strategies.

Cette recherche s’inscrit dans le contexte de la conception d’une filière originale comprenant la phytoextraction du nickel par la plante hyperaccumulatrice Alyssum murale, endémique des sols de serpentine d’Albanie et de sa valorisation de ce nickel, l’objectif étant d’arriver à un produit à haute valeur ajoutée. Les sols de serpentine peuvent être considérés comme une ressource secondaire. Ils contiennent des concentrations élevées en nickel mais à des teneurs insuffisantes pour être exploités par l’industrie minière. La plante Alyssum murale peut extraire et concentrer le nickel dans ses tissus. Le nickel présent dans la biomasse a pu être solubilisé quasiment totalement à l’acide sulfurique, en réacteur fermé puis à contre-courant en trois étapes. Cette lixiviation a produit une solution contenant du nickel lié à des molécules organiques ainsi que d’autres métaux et composés organiques. Les procédés de raffinage directs comme la précipitation sélective ou l’électroplaquage n’ont pas permis d’isoler le nickel. Deux voies ont été explorées : (i) l’extraction par un solvant organique sélectif du nickel (Cyanex 272) suivie d’une contre extraction par une solution aqueuse et électrodéposition et (ii) la cristallisation d’un sel double à partir du lixiviat préparé après incinération de la biomasse. La première voie a permis d’obtenir le nickel métal sous forme de cathode, la seconde a conduit au sel double sulfate de nickel et d’ammonium. Les produits ont été caractérisés par différentes techniques. Une étude technico-économique a montré le fort potentiel économique de la production de sel double / This research has been done in the context of the design of an original method aiming at obtaining high added value products of nickel, combining phytoextraction and valorization. Phytoextraction is conducted with the hyperaccumulating plant Alyssum murale, endemic species of serpentine soils in Albania. Serpentine soils can be considered as secondary resources: they contain high concentrations of nickel, which are not high enough for conventional mining techniques. The plant Alyssum murale can extract and concentrate nickel in its tissues. Nickel present in the biomass could be almost totally solubilized in batch reactor and with a 3 step countercurrent process. This leaching produced a solution containing nickel bound to organic molecules and other metals and organic compounds as well. Direct separation processes (e.g. selective precipitation and electrowinning) did not enable us to obtain nickel. Two methods have been investigated: (i) extraction by an organic nickel –selective solvent (Cyanex 272), extraction by an aqueous solution and electrowinning and (ii) crystallization of a double salt, nickel ammonium sulfate, from a leaching solution obtained from biomass ashes. Nickel products were characterized by different techniques. A technico-economical study showed the high commercial potential of the double salt production.

Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal.

Le procédé par coprécipitation est l’un des plus utilisé dans l’industrie nucléaire pour le traitement des effluents liquides radioactifs car il peut être appliqué à tous les effluents quelque soit leur composition. Ce procédé consiste à former in situ des particules solides par précipitation dans le but de capter sélectivement un ou plusieurs radioéléments. L’objectif de ce travail de thèse est de mettre en évidence les phénomènes impliqués lors de la coprécipitation d’un élément présent en faible concentration. Pour cela, cette étude propose une nouvelle modélisation des phénomènes de coprécipitation dont l’originalité tient dans la possibilité de simuler le phénomène hors équilibre thermodynamique et à l’échelle d’un réacteur chimique. Ce modèle, couplé avec la résolution du bilan de population, permet d’identifier l’influence des paramètres de procédés (débits, agitation…) sur la décontamination. Afin d’éprouver ce nouveau modèle, celui-ci est appliqué au traitement, dans les conditions industrielles, du strontium par le sulfate de baryum en réacteur continu et semi-fermé. A partir de ces simulations, des lois d’évolution de l’efficacité du traitement en fonction de différents paramètres de procédé (Temps de passage ou d’injection, agitation, concentration de BaSO4) ont été dégagées puis vérifiées expérimentalement. Cette étude permet de définir les meilleures conditions de traitement. Trois dispositifs (à recyclage, à lit fluidisé et réacteur/décanteur) permettant d’approcher ces meilleures conditions ont été testés avec succès. Ceux-ci ouvrent d’importantes perspectives pour la réduction de la quantité de boue produite. Deux brevets ont été déposés suite à ce travail / To decontaminate liquid nuclear wastes, the coprecipitation process is the most commonly used in nuclear field because it can be applied to any type of aqueous effluents whatever their composition may be. This process deals with the in situ precipitation of solid particles to selectively remove one or more radioelements. The aim of this PhD work is to investigate phenomena which take place during the coprecipitation of a trace component. To reach this objective, we have proposed a new modelling of the coprecipitation mechanism. The originality of this new approach lies in the possibility to simulate the phenomenon in non equilibrium conditions and at the reactor scale. This modelling combined with the resolution of the population balance, enable to identify the influence of process parameters (flowrates, stirring speed…) on crystal size and ultimately on decontamination. To test this new modelling, simulations of the coprecipitation of strontium ions with barium sulphate have been performed in continuous and semibatch reactors. Thanks to these simulations, laws of the treatment efficiency variation as a function of several process parameters (mean residence time, stirring speed, BaSO4 concentration) have been determined and experimentally verified. This study leads to the determination of optimal treatment conditions. Three apparatus (recycling apparatus, fluidised bed and reactor/settling tank) providing these optimal conditions have been successfully tested and offered significant outlooks for the reduction of the volume of sludge produced by the process. Two new processes are patent pending

Ce travail est consacré à l’étude d’un procédé d’oxydation avancée (POA) basé sur la génération de radicaux sulfates (SO4•-) pour l’élimination de substances pharmaceutiques dans le cadre du traitement d’effluents urbains. Quatre substances pharmaceutiques azotées (carbamazépine, diclofénac, sulfaméthoxazole et ciprofloxacine) appartenant à des familles thérapeutiques différentes ont été choisies en tant que contaminants modèles. L’évaluation de la performance cinétique des procédés basés sur la génération de HO• (H2O2/Fe(II) et UV-C/H2O2) et de SO4•- (HSO5-/Co2+, UV-C/S2O82- et UV-C/HSO5-) a été conduite dans des effluents de stations d'épuration traités biologiquement. La comparaison des procédés non photochimiques et photochimiques a été conduite dans les mêmes conditions optimales et montre que les procédés générant des SO4•- sont moins inhibés par la matrice environnementale que les procédés produisant HO•. La réaction de transfert électronique est mise en évidence par l’identification de produits de transformation des contaminants d’étude par chromatographie liquide couplée à un spectromètre de masse à haute résolution. Le début d’oxydation démarre par un transfert d’un électron sur les groupements azotés générant ainsi un radical cation qui réagit avec l’eau ou l’O2. La dégradation du sulfaméthoxazole est le cas le plus évident grâce à sa fonction amine primaire (aniline) qui se transforme en fonction nitro. On peut par conséquent envisager des nouvelles stratégies de traitement des eaux usées urbaines par la génération de SO4•-. / This work is devoted to the study of an alternative advanced oxidation process (AOP) generating sulfate radical (SO4•-) for the removal of pharmaceuticals in municipal wastewater effluents. Four nitrogen containing pharmaceuticals (carbamazepine, diclofenac, sulfamethoxazole and ciprofloxacin) belonging to different therapeutic classes were chosen as model contaminants. The evaluation of the kinetic performance of processes based on the generation of HO• (H2O2/Fe(II) and UV-C/H2O2 ) and SO4•- (HSO5-/Co2+, UV-C/S2O82- and UV-C/HSO5- ) was conducted in biologically treated effluent. Comparison of photochemical and non- photochemical processes performed under the same optimal conditions showed that the processes generating SO4•- are less inhibited by the environmental matrix than processes producing HO•. This electron transfer reaction is demonstrated by the identification of transformation products using liquid chromatography coupled to high resolution mass spectrometer. Oxidation of parent compounds starts by an electron transfer reaction on the nitrogen groups thereby generating a cation radical which further reacts with water or O2. The sulfamethoxazole degradation pathway gives more insights into this mechanism due to the primary amine moiety (aniline) which is converted into nitro function. This treatment system can be regarded as a new strategy for the treatment of urban wastewater contaminated by pharmaceutical residues through the generation of SO4•-.

O presente trabalho teve, por objetivo principal, analisar a remoção de sulfato em águas de drenagem ácida de minas em dois tipos de reatores anaeróbios, um com crescimento granular (UASB) e outro com biomassa aderida (RAHLF). Estudos anteriores publicados na literatura apresentam resultados positivos quanto ao tratamento anaeróbio de drenagem ácida de minas, entretanto, na maioria deles, é aplicado um tratamento preliminar à água residuária antes do tratamento principal. Esse trabalho avaliou a operação de reatores anaeróbios sem prévio tratamento da drenagem ácida sob diferentes variáveis. Para o reator anaeróbio horizontal de leito fixo (RAHLF), foram analisadas as variáveis relação DQO/\'SO IND.4\'POT.2-\', correção do pH afluente, carga de sulfato aplicada e a recirculação da fase líquida. Os resultados mostraram que a redução da carga de sulfato aplicada foi o fator determinante para os bons resultados de remoção, encontrados ao longo da operação dos reatores (70% de remoção de sulfato e 75% de remoção de DQO). A relação DQO/\'SO IND.4\'POT.2-\' também foi importante e quando utilizada a relação estequiométrica de 0,67, a eficiência de remoção de sulfato atingiu níveis superiores a 70% com pequeno acúmulo de ácido acético no efluente. Para a operação do reator anaeróbio de manta de lodo (UASB), as variáveis analisadas foram o volume da manta de lodo, a relação DQO/\'SO IND.4\'POT.2-\', a carga de sulfato aplicada e a recirculação da fase líquida. Como para o RAHLF, a redução da carga de sulfato aplicada foi essencial para o melhor funcionamento do UASB. A relação DQO/\'SO IND.4\'POT.2-\' de 1,0 promoveu melhora na eficiência do reator, quando comparada à relação estequiométrica e a recirculação no reator só foi positiva quando realizada com água de abastecimento, tendo o reator entrado em colapso quando a recirculação foi realizada com o efluente tratado. / The main objective of this work was to evaluate the sulfate removal from acid mine drainage in two types of anaerobic reactors, one with a granular sludge (UASB) and another with immobilized biomass (HAIB reactor). Previous published studies have showed positive results for the anaerobic treatment of acid mine drainage, however, in most of them, it was applied a pre-treatment operation. This study evaluated the operation of anaerobic reactors without pre-treatment of the acid mine drainage under different parameters. The parameters COD/\'SO IND.4\'POT.2-\' ratio, correction of affluent pH, sulfate loading and recirculation of the liquid phase were tested for horizontal-flow anaerobic immobilized biomass (HAIB) reactor. The results showed that the decrease in the sulfate loading was a determining factor for the successful sulfate removal found throughout the operation of the reactors. The COD/\'SO IND.4\'POT.2-\' ratio was also important and the removal efficiency of sulfate reached levels above 70% with a small accumulation of acetic acid in the effluent when using stoichiometric ratio of 0.67. For the operation of the upflow anaerobic sludge blanket (UASB) reactor, the parameters were the volume of the sludge blanket, the COD/\'SO IND.4\'POT.2-\' ratio, the sulfate loading and the recirculation of the liquid phase. Similarly ti the HAIB reactor, reducing the sulfate load was essential for obtaining better results. The COD/\'SO IND.4\'POT.2-\' ratio of 1.0 showed a improved sulfate removal efficiency for the UASB reactor when compared to stoichiometric ratio at 0.67 ant the recirculation in this reactor was only positive when carried out with tap water. The UASB reactor collapsed when recirculation was carried out whit the treated effluent.