Le recyclage des condensats d'évaporation dans l'étape de fermentation permettrait aux distilleries de diminuer leur consommation d'eau de forage et leur production d'effluents. Actuellement, les condensats sont traités par lagunage avant épandage et pourraient être recyclés comme eau de dilution pour la fermentation si les composés inhibiteurs qu'ils contiennent étaient éliminés : il s'agit de composés phénoliques, acides carboxyliques et dérivés du furane. L'étude du traitement a porté sur les procédés physico-chimiques présentant les meilleures capacités de rétention des composés inhibiteurs cibles : l'osmose inverse, l'échange d'ions et l'adsorption. L'étude des paramètres opératoires de ces procédés et de leurs combinaisons a permis d'optimiser leurs conditions d'application pour améliorer leur efficacité de rétention et de proposer leur mise en œuvre industrielle. L'impact des condensats diversement traités sur l'activité fermentaire des levures a été étudié lors de fermentations en continu. Le caractère fermentescible des condensats traités a été corrélé à l'efficacité de rétention du procédé. L'osmose inverse combinée à l'échange d'ions, permettant l'élimination de 99% des composés inhibiteurs cibles, est le seul procédé qui ne perturbe ni la croissance des levures ni leur production d'éthanol. A partir de cette combinaison on a dimensionné une unité traitant 100 m³.h⁻¹ de condensats. Selon les paramètres opératoires appliqués, on présente le bilan d'effluents produits et de réactifs consommés, ainsi que les installations correspondantes.

Sistemas de membranas filtrantes, principalmente os de osmose reversa, estão sendo cada vez mais utilizados em diversos seguimentos de empresas (farmacêutica, tratamento de água, alimentícia e química), devido à diminuição do preço dos elementos filtrantes e da alta qualidade do produto obtido. Apesar do preço dos elementos de osmose reversa terem caído nos últimos tempos, a substituição destes continua sendo o fator mais dispendioso de um sistema de osmose reversa. A autópsia de membranas é uma técnica utilizada para investigar a causa que levou à colmatação de um elemento, contribuindo no melhoramento do pré-tratamento da água de alimentação e consequentemente aumentando a vida útil dos elementos. O presente trabalho teve como objetivo incrementar a técnica de autópsia de membranas de osmose reversa através da análise da volatilização dos principais compostos inorgânicos presentes nestas membranas, modificação na metodologia de quantificação de açúcares e proteínas, comparação de diferentes técnicas de remoção do material depositado sobre as membranas e análise da distribuição de biofilmes sobre elementos colmatados de osmose reversa. A análise dos resultados mostrou que dentre os inorgânicos, ocorreu volatilização completa do cloreto de amônio e pequena variação no composto cloreto férrico; a quantificação de proteínas e açúcares, através da fortificação das amostras, apresentou valores diferentes quando comparados com os valores obtidos diretamente da curva padrão, devido à diferença de inclinação entre as retas de fortificação e padrão; os resultados também mostraram que a trituração foi mais eficiente na remoção do material aderido quando comparado com a raspagem e a sonicação e a distribuição de biofilmes se mostrou uniforme nos dois elementos analisados. / Filter membrane systems, especially reverse osmosis, are being increasingly used in various business segments (pharmaceutical, water treatment, food and chemical) due to decrease in the price of the filter elements and high quality product. Although the price of reverse osmosis elements have fallen in recent times, the replacement of the part remains more expensive a reverse osmosis system. The autopsy of membranes is a technique used to investigate the cause that led to clogging of one factor contributing to the improvement of pre-treatment of water feeding and consequently increasing the life of the elements. This study aimed to improve the technique of autopsy reverse osmosis membranes by examining the volatilization of major inorganic compounds present in these membranes, modification the methodology for quantification of sugars and proteins, comparison of different techniques for removal of material deposited on the membranes and distribution analysis of biofilms on elements obscured reverse osmosis. The results showed that among the Inorganic volatilization was full of ammonium chloride and small variation in the compound ferric chloride, the quantification of proteins and sugars, by fortifying the samples showed different values when compared with values obtained directly the standard curve due to the difference in slope between the lines of and fortification standard, the results also showed that the blending was more efficient in removing adhered material when compared with the scraping and sonication and distribution of biofilms showed uniform the two elements analyzed.

A água exerce papel fundamental nas diferentes fases do processo de fabricação de artigos para saúde (médico-hospitalares, farmacêuticos, e clínicos), exigindo elevado grau de pureza, que certifique a sua inocuidade. Portanto, se faz necessário maior controle dos sistemas de purificação de água e suas etapas de tratamento, onde a formação de biofilmes pode contaminar os artigos para saúde e, consequentemente, causar injúria a pacientes submetidos à aplicação dos mesmos. Embora os artigos médicos sejam esterilizados por óxido de etileno (ETO), seu processo de manufatura deve prever o mínimo acréscimo possível de contaminantes. Considerando que a água purificada e a esterilização dos artigos para saúde são fatores determinantes para o sucesso de sua aplicação, este trabalho foi dividido em duas partes distintas. A primeira parte aborda o controle das etapas de purificação da água, que é destinada à lavagem de componentes termoplásticos, que são utilizados na fabricação de artigos para saúde. Os níveis máximos de carga microbiana (expressos em ciclos de log10 UFC/100mL) encontrados ao longo do sistema de purificação de água foram: 3,48 log10 na água de entrada; 3,57 log10 nos filtros multimeios; 3,75 log10 nos abrandadores; 4,97 log10 no filtro de carvão ativado; 2,53 log10 na osmose reversa; 2,70 log10 no tanque de estocagem e distribuição; 2,56 log10 na lâmpada ultravioleta; 2,53 log10 nos filtros 0,05 µm; 1,98 log10 nos pontos de uso. Flavimonas oryzihabitans e Micrococcus luteus foram as bactérias Gram-negativa e Grampositiva, respectivamente, isoladas e identificadas com maior freqüência na água, em diferentes estágios do sistema, inclusive após a passagem dessa através das membranas de osmose reversa. A segunda parte do estudo teve como objetivo determinar o tempo de aeração necessário para que os oxigenadores de sangue e conjuntos de tubos de PVC, após esterilização por ETO, permaneçam em aeração, para dissipação dos resíduos de ETO. Avaliou-se também a potencialidade da proteína verde fluorescente (GFP) como biossensor no processo de esterilização. O processo de esterilização destes artigos médicos foi monitorado com indicadores biológicos Bacillus atrophaeus, proteína verde fluorescente (GFP) e controles de temperatura, pressão e umidade em ciclos de 2 h (ciclo curto), 4 h (meio ciclo) e 8 h (ciclo longo). As curvas de dissipação, determinadas por cromatografia gasosa, confirmaram níveis residuais menores que 25 ppm para ETO e etileno cloridrina (EC); e inferiores a 250 ppm para etileno glicol (EG), ao final do processo de esterilização para os oxigenadores; e, após 221 horas de aeração, para os conjuntos de tubos de PVC. Nos ciclos de esterilização, as reduções na intensidade de fluorescência da GFP ocorreram em função do tempo de exposição ao ETO; enquanto germinação de esporos e/ou crescimento de B. atrophaeus não foi observado. / The water exerts important paper in different phases of critical items manufacture in the health care units, pharmaceutical industries, hospitals and clinics, becoming necessary a rigorous control of the water purification systems, storage and distribution, in order to prevent biofilms formation and cross-contamination between devices and patients, who are submitted to critical articles and parenteral solution application. The sterilization of critical devices by ethylene oxide (ETO) should predict minimum addition of possible contaminants and residues. Considering that the purified water and the sterilization are crucial factors for medical devices, this work was divided in two parts. The first part evaluated continuously the stages of the system for the purification of the water, which purity level is critical and determines the quality of the washing of thermoplastic components used in the manufacture of critical items. The maximum levels of heterotrophic load (log10 UFC/100mL) found throughout the water purification system were: 3.48 log10 in the water inlet; 3.57 log10 in the multimedium filters; 3.75 log10 in the softeners; 4.97 log10 in the activated carbon filter; 2.53 log10 in the reverse osmosis; 2.70 log10 in the tank of storage and distribution; 2.56 log10 in the UV lamp; 2.53 log10 in the 0.05µm filters; 1.98 log10 in the consumption points. Flavimonas oryzihabitans and Micrococcus luteus were the main Gram-negative and Grampositive bacteria, respectively found in the purified water after reverse osmosis. The second part of this study had as objective the determination of the needed aeration time for blood oxygenators and sets of PVC tubing must be kept in aeration room for dissipation of ETO residues; and also evaluated the possibility of GFP as biosensor. ETO is used as in a mixture (10% ETO and 90% CO2). Residual levels of ETO and its derivatives, ethylene chloridrin (ECH) and ethylene glycol (EG), which remain in these devices, must be controlled to prevent serious injuries to the patients. The sterilization process of the oxygenators and sets of PVC tubing was monitored with Bacillus atrophaeus and fluorescent green protein (GFP). The temperature, pressure and humidity were controlled in the sterilization cycles of 2 h (short cycle), 4 h (half cycle) and 8 h (long cycle). The dissipation curves of the residues were determined by gaseous chromatography and the residual concentrations were lower than 25 ppm of ETO and ECH and lower than 250 ppm of EG immediately after the sterilization processes for oxygenators and after 221 hours of aeration for the sets of PVC tubing. Reductions in the fluorescence intensity of GFP were observed as a function of the exposition time to the ETO. No growth of B. atrophaeus spores was observed after cycles.

Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2017-04-27T13:51:34Z No. of bitstreams: 1 2012 - Andr? Luis R. de Souza.pdf: 1971622 bytes, checksum: 5237bc23d365c59e774d9f8776efabf1 (MD5) / Made available in DSpace on 2017-04-27T13:51:34Z (GMT). No. of bitstreams: 1 2012 - Andr? Luis R. de Souza.pdf: 1971622 bytes, checksum: 5237bc23d365c59e774d9f8776efabf1 (MD5) Previous issue date: 2012-03-06 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico - CNPq / Camu-camu is a native fruit from the Amazonian region, cultivated in the margins of rivers, lakes and Amazonian creeks called igarap?s. It is known as one of the fruit with the highest content of vitamin C. Reverse osmosis is a membrane concentration process in which the applied pressure is higher than the juice osmotic pressure. Such process favors the solvent permeation from the region with the highest concentration to the one with the lowest. Osmotic evaporation is another membrane concentration process in which a porous hydrophobic membrane separates the solution that is going to be concentrated from a concentrate brine solution. Microencapsulation is the process in which an active agent is entrapped by means of a polymer cover. Such process promotes the release of these active agents under specific conditions. The aim of this work is to evaluate the use of membrane separation processes and microencapsulation for the processing of camu-camu fruits. The camu-camu pulp, which has been obtained through the depulping of camu-camu fruits, was first centrifuged, in order to decrease its suspended solids content, and clarified by microfiltration with polysulfone membranes. Six clarification processes have carried out at 2.5 bar transmembrane pressure and 45?C. The clarified juice was concentrated by reverse osmosis at 60 bar and 20 ?C. The avarage permeate flux has been of 11.3 L/hm2. The preconcentrated juice had 28.8?Brix and the concentration degree of the process was 3.8. The pre-concentrated juice has been concentrated by osmotic evaporation in a laboratorial system with polytetrafluoroethylene membrane. The process presented an average pemeate flux of 2.4 Kg/hm2. The soluble solids content of the concentrated juice was of 56.6 ?Brix, presenting a concentration degree of 1.98. The retentate fraction of the microfiltration process was microencapsulated in a spray dryer. Three encapsulation agents were evaluated: starch, maltodextrin and the mixture of both. The values presented for the physicochemical caracterization of the pre-concentrated and concentrated camu-camu juices indicate that there has been an increase both in the physical characteristics of the juice, such as soluble solids, total solids and acidity, and in the concentration of camu-camu bioactive compounds. The dehydrated camu-camu juice presented a high concentration of bioactive substances. Nevertheless, there has been no stability of such compounds during storage. Through the results obtained in the present work, it is possible to observe that the integration of membrane processes proved efficient in the concentration of camu-camu juice, with a final product of high nutritional value / O camu-camu ? um fruto nativo da regi?o amaz?nica, cultivado as margens de rios, lagos e igarap?s. ? reconhecido como um dos frutos com um dos maiores teores de vitamina C. Osmose inversa ? o processo de concentra??o por membranas onde a press?o aplicada ? maior que a press?o osm?tica do suco, favorecendo a permea??o do solvente da regi?o de maior concentra??o para regi?o de menor concentra??o. Evapora??o osm?tica ? um outro processo de concentra??o, onde uma membrana hidrof?bica porosa separa a solu??o que ser? concentrada e uma salmoura concentrada. A microencapsula??o ? o processo onde um agente ativo ? protegido por meio de uma cobertura de pol?meros, ocorrendo a libera??o desses agentes ativos em condi??es espec?ficas. O objetivo desta disserta??o foi avaliar o uso dos processos de separa??o com membranas e microencapsulamento para o processamento de suco de camu-camu. Os frutos de camu-camu foram despolpados, sendo o suco submetido a centrifuga??o, com o objetivo de reduzir os s?lidos em suspens?o, e posteriormente clarificado por microfiltra??o em um sistema de membranas de polissulfona. Foram realizados seis processos de clarifica??o a 2,5 bar e 45?C. O suco clarificado foi pr?-concentrado por osmose inversa a 60 bar e 20 ?C. O fluxo permeado m?dio foi de 11,3 L/hm2. O suco pr?-concentrado apresentou teor de s?lidos sol?veis de 28,8?Brix e grau de concentra??o de 3,8. O suco pr?-concentrado foi processado por evapora??o osm?tica em um sistema laboratorial constitu?do por membranas de politetrafluoretileno. O processo apresentou fluxo m?dio permeado de 2,4 kg/hm2. O teor de s?lidos sol?veis do suco concentrado foi de 56,6 ?Brix, apresentando um grau de concentra??o de 1,98. O processo de microencapsula??o da fra??o retida do suco de camucamu foi realizado em um spray dryer Buchi Modelo B-190. Foram realizados tr?s ensaios com tr?s formula??es diferentes: mistura entre amido e maltodextrina, somente amido e somente maltodextrina. Os valores apresentados para a caracteriza??o f?sico-qu?mica do suco de camu-camu pr?-concentrado e concentrado indicam que houve um aumento nos s?lidos sol?veis e totais e da acidez, bem como no teor das subst?ncias bioativas do camucamu. O suco de camu-camu desidratado apresentou alto teor de subst?ncias bioativas, onde a estabilidade desses compostos durante o per?odo de armazenamento n?o foi alcan?ada. Observa-se que a integra??o dos processos com membranas se mostrou eficaz na concentra??o do suco de camu-camu, obtendo um produto com alta qualidade nutricional.

A água exerce papel fundamental nas diferentes fases do processo de fabricação de artigos para saúde (médico-hospitalares, farmacêuticos, e clínicos), exigindo elevado grau de pureza, que certifique a sua inocuidade. Portanto, se faz necessário maior controle dos sistemas de purificação de água e suas etapas de tratamento, onde a formação de biofilmes pode contaminar os artigos para saúde e, consequentemente, causar injúria a pacientes submetidos à aplicação dos mesmos. Embora os artigos médicos sejam esterilizados por óxido de etileno (ETO), seu processo de manufatura deve prever o mínimo acréscimo possível de contaminantes. Considerando que a água purificada e a esterilização dos artigos para saúde são fatores determinantes para o sucesso de sua aplicação, este trabalho foi dividido em duas partes distintas. A primeira parte aborda o controle das etapas de purificação da água, que é destinada à lavagem de componentes termoplásticos, que são utilizados na fabricação de artigos para saúde. Os níveis máximos de carga microbiana (expressos em ciclos de log10 UFC/100mL) encontrados ao longo do sistema de purificação de água foram: 3,48 log10 na água de entrada; 3,57 log10 nos filtros multimeios; 3,75 log10 nos abrandadores; 4,97 log10 no filtro de carvão ativado; 2,53 log10 na osmose reversa; 2,70 log10 no tanque de estocagem e distribuição; 2,56 log10 na lâmpada ultravioleta; 2,53 log10 nos filtros 0,05 µm; 1,98 log10 nos pontos de uso. Flavimonas oryzihabitans e Micrococcus luteus foram as bactérias Gram-negativa e Grampositiva, respectivamente, isoladas e identificadas com maior freqüência na água, em diferentes estágios do sistema, inclusive após a passagem dessa através das membranas de osmose reversa. A segunda parte do estudo teve como objetivo determinar o tempo de aeração necessário para que os oxigenadores de sangue e conjuntos de tubos de PVC, após esterilização por ETO, permaneçam em aeração, para dissipação dos resíduos de ETO. Avaliou-se também a potencialidade da proteína verde fluorescente (GFP) como biossensor no processo de esterilização. O processo de esterilização destes artigos médicos foi monitorado com indicadores biológicos Bacillus atrophaeus, proteína verde fluorescente (GFP) e controles de temperatura, pressão e umidade em ciclos de 2 h (ciclo curto), 4 h (meio ciclo) e 8 h (ciclo longo). As curvas de dissipação, determinadas por cromatografia gasosa, confirmaram níveis residuais menores que 25 ppm para ETO e etileno cloridrina (EC); e inferiores a 250 ppm para etileno glicol (EG), ao final do processo de esterilização para os oxigenadores; e, após 221 horas de aeração, para os conjuntos de tubos de PVC. Nos ciclos de esterilização, as reduções na intensidade de fluorescência da GFP ocorreram em função do tempo de exposição ao ETO; enquanto germinação de esporos e/ou crescimento de B. atrophaeus não foi observado. / The water exerts important paper in different phases of critical items manufacture in the health care units, pharmaceutical industries, hospitals and clinics, becoming necessary a rigorous control of the water purification systems, storage and distribution, in order to prevent biofilms formation and cross-contamination between devices and patients, who are submitted to critical articles and parenteral solution application. The sterilization of critical devices by ethylene oxide (ETO) should predict minimum addition of possible contaminants and residues. Considering that the purified water and the sterilization are crucial factors for medical devices, this work was divided in two parts. The first part evaluated continuously the stages of the system for the purification of the water, which purity level is critical and determines the quality of the washing of thermoplastic components used in the manufacture of critical items. The maximum levels of heterotrophic load (log10 UFC/100mL) found throughout the water purification system were: 3.48 log10 in the water inlet; 3.57 log10 in the multimedium filters; 3.75 log10 in the softeners; 4.97 log10 in the activated carbon filter; 2.53 log10 in the reverse osmosis; 2.70 log10 in the tank of storage and distribution; 2.56 log10 in the UV lamp; 2.53 log10 in the 0.05µm filters; 1.98 log10 in the consumption points. Flavimonas oryzihabitans and Micrococcus luteus were the main Gram-negative and Grampositive bacteria, respectively found in the purified water after reverse osmosis. The second part of this study had as objective the determination of the needed aeration time for blood oxygenators and sets of PVC tubing must be kept in aeration room for dissipation of ETO residues; and also evaluated the possibility of GFP as biosensor. ETO is used as in a mixture (10% ETO and 90% CO2). Residual levels of ETO and its derivatives, ethylene chloridrin (ECH) and ethylene glycol (EG), which remain in these devices, must be controlled to prevent serious injuries to the patients. The sterilization process of the oxygenators and sets of PVC tubing was monitored with Bacillus atrophaeus and fluorescent green protein (GFP). The temperature, pressure and humidity were controlled in the sterilization cycles of 2 h (short cycle), 4 h (half cycle) and 8 h (long cycle). The dissipation curves of the residues were determined by gaseous chromatography and the residual concentrations were lower than 25 ppm of ETO and ECH and lower than 250 ppm of EG immediately after the sterilization processes for oxygenators and after 221 hours of aeration for the sets of PVC tubing. Reductions in the fluorescence intensity of GFP were observed as a function of the exposition time to the ETO. No growth of B. atrophaeus spores was observed after cycles.

Cette thèse a pour objectif d'étudier les potentialités des pompes électrocinétiques pour des applications de type refroidissement de composants de l'électronique de puissance. En effet, les pompes mécaniques utilisées aujourd'hui présentent des problèmes en terme de fiabilité, de bruit, de coût et de volume. Après une étude bibliographique et comparative entre les différentes pompes statiques fonctionnant à partir d'un champ électrique, nous avons choisi d'étudier plus en détail les pompes électro-osmotiques poreuses. Une modélisation de ce type de pompe a été proposée et validée expérimentalement. Nous avons également développé une formulation analytique de l'efficacité thermodynamique optimale d'une pompe électroosmotique poreuse. Deux types de fonctionnement ont été abordés dans cette thèse : une étude avec une tension continue et une autre étude avec une tension alternative. Nous avons mis en oeuvre la pompe fonctionnant en alternatif dans une boucle de refroidissement diphasique. Une densité de flux de 100W/cm2 a pu être évacuée. D'autres applications industrielles de la pompe électro-osmotique ont également été envisagées.

Cette thèse de doctorat présente une étude expérimentale des propriétés rhéologiques d’électrolytes confinés et de la mécanique des doubles couches électrostatiques.Afin d’étudier simultanément les propriétés d’équilibre et de transport d’électrolytes confinés proches de parois électriquement chargées, nous avons développé un appareil à forces de surfaces dynamique. Cette technique combine à la fois des mesures à l’équilibre, à l’instar des appareils à forces de surfaces classiques, et des mesures dynamiques permettant de caractériser les phénomènes de transport.Nous avons tout d’abord étudié le cas d’électrolytes très dilués. Nous avons montré l’existence d’une sur-dissipation induite par les ions issus des électrolytes par rapport à un comportement newtonien classique. De plus, nous avons mis en évidence un comportement élastique des doubles couches électrostatiques dépendant de la fréquence. Une approche théorique vient compléter et expliquer en partie les résultats expérimentaux.Enfin nous nous sommes intéressés à la dynamique d’électrolytes concentrés : les liquides ioniques. Nous avons étudié l’influence, sur la viscosité et les propriétés du liquide à l’interface solide-liquide, d’un champ électrique intense appliqué perpendiculairement à l’écoulement, comme rencontré dans les super-condensateurs. / This thesis presents an experimental study of rheological properties of confined electrolytes and mechanics of electric double layer.In order to study simultaneously equilibrium and transport of confined electrolytes nearby charged surfaces, we developed a dynamic surface force apparatus. This technique enables both steady state measurements, as provided by common surface forces apparatus, and dynamic measurements that allow characterizing the transport phenomenona.First, we showed the existence of an over-dissipative behavior of weak electrolytes compared to a classical newtonian fluid. Furthermore we highlighted a frequency dependence of the EDL elastic behavior. Alongside, a theoretical approach completes and explains partially the experimental observations.Finally we studied the dynamics of ionic liquid, a type of concentrated electrolytes. We looked at the influence of a huge electric field, applied perpendicularly to the surfaces, on the viscosity and the properties of the liquid nearby the surfaces, as found in super-capacitors.

L'industrie minière produit d'énormes quantités de déchet (millions de tonnes par an), souvent sous forme de boue à cause de la forte teneur en eau et en argile. Ces boues liquides sont problématiques car elles se consolident très lentement : elles limitent la réhabilitation des parcs à résidus où elles sont stockées et augmentent le risque de rupture des barrages entourant les parcs à résidus (coulée de boue). Améliorer l'assèchement des boues minières est nécessaire afin d'augmenter la stabilité des parcs à résidus et de recycler l'eau contenue dans la boue. La solution proposée dans cette thèse consiste à insérer des géocomposites de drainage (GCP) dans les parcs à résidus afin de permettre à l'eau contenue dans la boue de s'évacuer. Pour mobiliser l'eau dans ces boues à faible conductivité hydraulique, deux phénomènes ont été investigués : la consolidation des boues sous contrainte mécanique et la migration de l'eau par électro-osmose (EO). Afin d'attester de la faisabilité d'appliquer ces 2 phénomènes avec des GCP, chacune des fonctions des GCP a été évaluée : les fonctions de base (filtration et drainage) pour provoquer l'asséchement mécanique et une nouvelle fonction de conduction électrique pour appliquer l'EO.La filtration de boue par géotextile (GTX) a été investiguée car contrairement à la filtration de sol, elle demeurait peu décrite dans la littérature et semblait délicate à cause de l'argilosité de la boue. Des tests de filtration sous pression ont permis de tester 8 GTX avec une même boue argileuse, puis 8 boues de granularités différentes avec un même GTX. Les résultats indiquent que les GTX n'ont un impact qu'au début de la filtration : ils retiennent les particules les plus grossières ce qui induit la formation d'un gâteau de filtration qui devient rapidement l'élément filtrant, le GTX n'est alors plus qu'un support. Une même boue filtrée par 8 GTX différents conduit à un même assèchement alors que les 8 boues différentes filtrées avec un même GTX conduisent à 8 assèchements différents : l'assèchement final est contrôlé par la composition de la boue et est totalement indépendant du GTX utilisé. Ces essais de filtration ont permis d'évaluer l'assèchement mécanique des boues : la pression appliquée (50kPa) conduit à l'expulsion de l'eau libre, alors que l'eau liée reste dans la boue. Cela est dû aux différents niveaux de liaison de l'eau dans la boue : l'eau liée ne peut être extraite mécaniquement. Ainsi les fonctions de base des GCP provoquent un asséchement mécanique du à l'augmentation de la contrainte lors du remplissage des parcs à résidus. En revanche, l'asséchement mécanique est limité à l'extraction de l'eau libre ; il est apparu essentiel de proposer un nouveau moteur pour extraire l'eau liée.La principale innovation de ce travail est l'ajout d'une nouvelle fonction au GCP : l'ajout d'éléments conducteurs dans les GCP permet d'appliquer l'EO dans les boues. Ce phénomène permet de mobiliser une partie de l'eau liée en imposant un courant électrique. Des prototypes de GCP électrocinétique (eGCP) ont été développés et testés dans un dispositif expérimental dédié. Les résultats montrent que la filtration et la conduction électrique sont assurées efficacement par les eGCP disposés de part et d'autre de la boue. La boue testée est issue des sables bitumineux (FFT) et est très problématique car sa consolidation est extrêmement lente. Les résultats obtenus sont très encourageants : la phase mécanique porte la siccité de la boue de 45% à 61%, puis l'EO permet d'atteindre une siccité de 77% et une résistance au cisaillement de 77 kPa, alors que la réglementation exige d'atteindre 10 kPa.Pour conclure, les différentes expérimentations montrent que les boues minières peuvent être asséchées par des GCP en cumulant les effets de la compression mécanique, grâce aux fonctions classiques des GCP et de l'EO grâce à l'ajout d'une nouvelle fonction de conduction électrique. Cette solution a fait l'objet d'un brevet / A host of mining practices produces huge quantity of fine-grained mineral sludges whose disposal in ponds is often challenging. The key problem caused by these sludges is their very poor geotechnical properties, which are caused by their high water and clay content. These sludges are hard to dewater because of their low hydraulic conductivity. Dewatering sludges to increase its shear strength and reduce the volume of material to be contained thus represents a preferred path to reduce the risk of pond's failure, reduce the pond's footprint, and maximize water recycling. To dewater mining sludges, the solution foreseen in this PhD is to intercalate some geocomposites (GCPs) layers within the sludge-disposal area to create draining horizons to permit mechanical dewatering and to apply electro-osmosis (EO) across sludges layers to induce water migration. To evaluate the efficiency of GCPs at enhancing sludges dewatering by both of these phenomena, the different functions of GCPs (filtration, drainage, and electric conduction) were experimentally investigated during this PhD.To study sludge filtration by geotextile (GTX), pressure filtration tests were used to filter 8 different high-clay-content sludges with 8 different nonwoven GTXs. Only a few studies have considered the filtration of sludge by GTXs. The sludges were formulated by mixing kaolinite and silt to obtain 8 different grain-size distributions. The results indicate that sludges can be filtered with nonwoven GTXs selected on the basis of their pore-opening size. In addition, only during the early stage of filtration GTXs really influence filtering because it is at this stage that, by retaining coarser particles, they allow progressive formation of filter cake. Upon forming, the filter cake becomes the major contributor to particle retention. The sludge composition is found to be the most significant factor affecting the final state of dewatering. In other words, the GTX does not control the final dewatering; the sludge itself controls the final solid content. These filtration tests showed that mechanical dewatering is effective for removing free water, but bounded water remains in the sludge because of the high bonding forces between water and solid matter. Facing this limitation of mechanical dewatering, a new way to extract bounded water had to be proposed.The main innovation brought by this PhD concerns the addition of a new function to GCP, by adding conductive elements into the GCP to apply EO in the sludge. Electro-osmosis (EO) forces water to migrate from anode to cathode and is sufficient to remove a significant portion of bounded water that cannot be removed by mechanical dewatering. Some prototypes of electro-kinetics GCP (eGCP) were developed, and tested in a new laboratory setup. This experimental device was developed to evaluate simultaneously the different functions of eGCPs, namely, drainage or filtration and electrical conductivity. It has the particularity that it uses eGCPs as both a draining medium and electrode. The results show that fluid fine tailings (FFTs), a particularly hard to dewater sludge from oil-sand exploitation, are significantly dewatered by the combination of normal stress compression, and then EO treatment: the FFT solids content increased from 45% to 61% during the compression phase and to 77% during the EO phase. The applied treatment led to a significant consolidation of the FFT: shear strength increased from zero to about 77 kPa which is significantly greater than the 10 kPa required by government regulations.To conclude, eGCPs can drain water expulsed during sludge consolidation in response to the filling of the disposal area, thanks to the classical function of GCP, as well as impose a voltage across FFT to displace water by electro-osmosis from anode to cathode, thanks to conductive elements embedded in eGCP. This solution was patented at the end of the PhD.

Submitted by Lara Oliveira (lara@ufersa.edu.br) on 2017-02-01T20:26:32Z No. of bitstreams: 1 AndréMO_TESE.pdf: 5450289 bytes, checksum: 5882a0a67b8d1b236c9a9b7e9ec60dfb (MD5) / Approved for entry into archive by Vanessa Christiane (referencia@ufersa.edu.br) on 2017-03-21T14:53:28Z (GMT) No. of bitstreams: 1 AndréMO_TESE.pdf: 5450289 bytes, checksum: 5882a0a67b8d1b236c9a9b7e9ec60dfb (MD5) / Approved for entry into archive by Vanessa Christiane (referencia@ufersa.edu.br) on 2017-03-21T15:07:13Z (GMT) No. of bitstreams: 1 AndréMO_TESE.pdf: 5450289 bytes, checksum: 5882a0a67b8d1b236c9a9b7e9ec60dfb (MD5) / Made available in DSpace on 2017-03-21T15:07:20Z (GMT). No. of bitstreams: 1 AndréMO_TESE.pdf: 5450289 bytes, checksum: 5882a0a67b8d1b236c9a9b7e9ec60dfb (MD5) Previous issue date: 2016-07-15 / In spite of the fact that crystalline basement predominates with brackish water wells in Brazilian thirstland, desalination technology by reverse osmosis enables its potabilization. Since the late nineties, reverse osmosis desalination devices have been deployed in order to meet the water demand for human consumption, especially in the rural Northeast. Nevertheless, difficulties are present in such deployment like lack of operation and proper maintenance, causing stoppage thereof and producing high-level reject brine, which is usually discharged to the ground without any criteria, and its main consequence has been soil salinity increase over time. Thus, this works aims at evaluating the outcome of the reverse osmosis desalination discharge and its influence in physicochemical attributes of distinct receiver soils in rural communities from Potiguar west. This research was conducted between 2013 and 2014. At first, the communities which were supplied by catchment and treatment of desalinated water centers were registered through a cadastral survey. In order to do so, four data collection expeditions took place in different periods, raining season and drought, on the soils receiving reject brine. Three distances were used (0, 1 and 2 meters from the discharge points) with two layers for each point (0-20cm and 20-40 cm) as well as the evaluation of a) the reverse osmosis treated water quality, b) the well, c) the reject brine. Physicochemical attributes of water for irrigation was also analyzed as well as soil samples for a fertility evaluation. Data were subjected to statistical average tests by Scott Knott to verify the behavior within the points and layers according to each period and between all four periods. The waters were classified according to its use for irrigation; leakage risks and toxicity in plants. The soils were classified according to salinity, Ph considering CE and PST. In the monitored rural communities, the reversed osmosis water treatment stations produce desalinated water with low concentrations of salts, with 68% of all samples are in C1S1 rating class; 25% in C2S1 and class; only 7% in C3S1 class. Regarding the reject brine, 93% of waste water samples were classified as C3 or C4 during the four collecting periods, that is, at high or extremely high salinization risk. The different types of receiver soils of reject brine coming from such communities show meaningful alteration of their attributes and of their qualities throughout the periods, being that more noticeable during the drought periods and on the layers of soils with greater amount of clay, promoting different ratings for the same soil, being such ratings influenced directly by the waste water from desalination process / Ainda que, no Semiárido brasileiro, predomine o embasamento cristalino, com poços de água salobra, a tecnologia da dessalinização permite a sua potabilização. Desde o final da década de 1990, vem sendo implantados equipamentos de dessalinização por osmose reversa visando o atendimento da demanda hídrica para consumo humano, especialmente na zona rural do Nordeste. No entanto, dificuldades estão presentes na implantação dos equipamentos, tais como a falta de operação e manutenções adequadas que causam a paralisação dos mesmos, e a produção de rejeitos com elevados teores de sais, normalmente despejados ao solo sem qualquer critério, cujo maior impacto tem sido o aumento da salinidade do solo ao longo do tempo. Desta forma, o objetivo deste trabalho foi avaliar o rejeito gerado pela osmose reversa e sua influência nas alterações dos atributos físico-químicos de distintos solos receptores em comunidades rurais do Oeste Potiguar. A pesquisa ocorreu no período de 2013 e 2014, inicialmente, foram identificadas as comunidades abastecidas com as unidades de captação e tratamento de água por dessalinização, por meios de um levantamento cadastral. Para isto, foram realizadas 4 campanhas de coletas em diferentes períodos de seca e chuva nos solos receptores do rejeito salino, usando três distâncias (0; 1 e 2 metros do ponto de despejo), com duas camadas para cada ponto (0-20 e 20-40 cm), bem como avaliação da qualidade das águas tratadas por osmose reversa, poço e rejeito salino, dentro de cada período. Foram analisados atributos físico-químicos das águas para fins de irrigação e as amostras de solo para avaliação da fertilidade. Os dados foram submetidos a testes estatísticos de médias, por Scott Knott, verificando o comportamento dentro dos pontos e camadas de cada período e entre os 4 períodos. As águas foram classificadas quanto ao uso na irrigação; aos riscos de infiltração e toxicidade em plantas. Os solos foram classificados de acordo com a salinidade, considerando pH, CEes e PST. As estações de tratamento de água por osmose reversa nas comunidades rurais monitoradas produzem uma água dessalinizada com concentrações baixas de sais, com 68% do total das amostras estão na classe de classificação C1S1; 25% na classe C2S1 e; apenas 7% na classe C3S1. Com relação ao rejeito gerado, 93% das amostras de água de rejeito se classificaram como C3 ou C4 nos quatro períodos de coleta, ou seja, águas de alto ou extremamente alto risco de salinização. As diferentes classes de solos receptores do rejeito salino das comunidades apresentaram alterações significativas dos seus atributos e sua qualidade ao longo dos períodos, sendo mais evidente nos períodos secos e camadas de solos com maior presença de argila, promovendo classificações distintas para um mesmo solo, influenciadas diretamente pela água de rejeito do processo de dessalinização / 2017-02-01

L'électrodialyse peut être utilisée pour traiter des effluents salins contenant de la matière organique. La compréhension des mécanismes de transfert (eau, ions, espèces organiques) à travers les membranes échangeuses d'ions et particulièrement l'influence de la composition ionique est un point clé vis-à-vis des performances du procédé. L'objectif de cette thèse est l'étude du transfert et la relation avec les performances de dessalement. Les nombres d'hydratation des ions sont tout d'abord calculés à partir des mesures du transfert des ions et de l'eau. Ils sont indépendants du courant et de la composition saline. La comparaison avec des valeurs de la littérature montre que les membranes ont peu d'effet sur l'hydratation des ions. Le transfert d'espèces organiques est ensuite étudié pour différentes compositions salines. Outre la diffusion, une contribution additionnelle est mise en évidence (convection pour les espèces neutres, migration pour les espèces chargées). Pour les espèces neutres, diffusion et convection sont du même ordre de grandeur et fixées par l'effet stérique. Des tendances inverses sont obtenues concernant l'hydratation des ions, la diffusion étant limitée par les modifications des membranes, la convection étant limitée par l'hydratation des espèces organiques en solution. Pour les espèces chargées, la migration domine la diffusion, les deux contributions étant influencées par la présence de sel. Les performances de dessalement sont enfin discutées sur la base d'un modèle phénoménologique à 4 paramètres liés au transfert de l'eau, des ions et des espèces organiques. La robustesse du modèle est validée pour différentes conditions. Ce travail montre que l'électrodialyse est une technologie très prometteuse pour le dessalement d'effluents contenant de la matière organique. / Electrodialysis can be used to treat saline water containing organic solute, separating organic solutes from salt. The understanding of salt, water and organic solute transfer through ion- exchange membranes and especially the influence of salt composition is a key factor regarding the process performances. The aim of the Thesis is to investigate the mass transfer and the relationship with the desalination performance. Firstly, hydration numbers of individual ion transferring through the membranes are computed based on experimental measurements of ion- water flux. They are independent from the salt compositions and current. Comparison with literatures values shows that the membranes have a weak influence on the ion hydration. Secondly, the transfer of different organic solutes is investigated with different salt compositions. Two contributions are pointed out, diffusion and additional one (convection for neutral solute, migration for charged one). For neutral solutes, diffusion and convection are comparable and both fixed by steric effect. Ion hydration leads to reversed trend for diffusion due to membrane swelling and convection due to solute dehydration. For charged solute, migration is more important than diffusion, both being influenced by the presence of salt. Then, desalination performance is discussed based on a phenomenological model, consisting of 4 parameters, related to ion, water and organic solute transfer respectively. The robustness of the model is demonstrated for different conditions. This work shows that electrodialysis can be a very promising process for the desalination of saline water containing organic solutes.