Дисертації з теми "Emulsions huile dans eau"
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Dridi, Wafa. "Influence de la formulation sur l'oxydation des huiles végétales en émulsion eau-dans-huile." Thesis, Bordeaux, 2016. http://www.theses.fr/2016BORD0102/document.
Повний текст джерелаOxidation is ubiquitous in lipids and causes degradation of organoleptic and nutritional qualities of foods. Lipid oxidation depends on various parameters (temperature, light, transition metals, lipid dispersion state …) that have to be controlled during food processing and storage. In this context, lipid oxidation was followed by measuring the content of primary oxidation products, for lipids in bulk phase and in water-in-oil emulsions. Different edible oils were chosen for their contents of α-linolenic acid (18: 3 n-3). Emulsions were formulated at varying polyglycerol polyricinoleate (PGPR)/distilled monoglycerides concentration ratios (surfactant ratio), with or without the presence of pro-oxydant metals or chelators. In all experiments, the aqueous volume fraction (40%) and the droplet mean diameter (1 μm) remained constant. Besides this study, an innovative and rapid method based on differential microcalorimetry was developed for monitoring the kinetics of lipid oxidation. The oxidability of the studied oils was related to their content in α-linolenic acid according the following order: linseed oil> camelina oil> rapeseed oil> olive oil. The rate of lipid oxidation increased with the iron sulfate concentration in the water phase. The iron valence or the replacement of iron by copper had no significant impact on the oxidation kinetics. However, both the chemical nature of the counter ion (molecular weight, chelating power) and the proportion of PGPR used to stabilize the emulsions were influential factors. On the whole, our results suggest that surfactants at the water-oil interface do not prevent pro-oxidant species to interact with lipids in the continuous phase but that their organization at the interface is a key parameter for controlling lipid oxidation
Lignel, Sarah. "Emulsions eau-dans-huile générées par un procédé microfluidique : contribution à l'étude de la congélation de l'eau dispersée en émulsion." Thesis, Compiègne, 2014. http://www.theses.fr/2014COMP2143/document.
Повний текст джерелаThis thesis takes place in the framework of the European project FASES (Fundamentaland Applied Studies on Emulsion Stability). The aim of this project is to understand the phenomena responsible for emulsions destabilization, in relation with the interfacial properties of these systems. The research work described in this thesis is divided into twoparts : the first part deals with the creation of water-in-oil emulsion droplets in a microfluidic device, and in the second part, the influence of the size and the state of dispersion of the droplets on the crystallization of dispersed water is analyzed.To begin with, the operating conditions required to create emulsion droplets by microfluidic were studied. Two modes of introduction of the liquid phases, based on flow and pressure-driven techniques, were used to create the droplets. Maps of the droplet formation regions were drawn as a function of the applied flow rates and pressures. In order to compare the two processes, a model based on the analogy between electrical and microfluidic circuits was proposed.Then, emulsions obtained with the microfluidic device were analyzed by calorimetry and thermo-microscopy. The experimental results evidenced different droplet crystallization processes, depending on the system parameters (oil phase viscosity, droplet size …). The water freezing signals strongly depend on the state of dispersion of the droplets, showing themajor role of droplet sedimentation in the emulsion destabilization process
Caubet, Sylvain. "PROCEDES BASSE ENERGIE POUR LA PRODUCTION D'EMULSIONS TRES CONCENTREES HUILE DANS EAU : CARACTERISATION, INTENSIFICATION ET APPLICATIONS." Phd thesis, Université de Pau et des Pays de l'Adour, 2010. http://tel.archives-ouvertes.fr/tel-00609838.
Повний текст джерелаCaubet, Sylvain. "Procédés basse énergie pour la production d’émulsions très concentrées huile dans eau : caractérisation, intensification et applications." Pau, 2010. http://www.theses.fr/2010PAUU3035.
Повний текст джерелаHigh Internal Phase Ratio (HIPR) emulsions are encountered in a wide variety of industrial applications: agrochemicals, petrochemical, cosmetics etc. The aim of this study is to characterize a new low energy mixer called two-rod mixer (TRM). This TRM allows the creation in one step of HIPR emulsion of viscous oil (91%) in water. The different phases of the HIPR emulsification in the batch TRM (B-TRM) have been highlighted, as well as their characteristics times. We show that it is possible to control the droplet size distribution and so the properties of the HIPR made. Furthermore, the energy input during the emulsification is relatively low. Lastly, this batch process has been transposed in a continuous one (C-TRM) that conserves the main characteristics of the batch process: controlled production of uni-modal HIPR emulsion with a low energetic cost and without heating of fluids
Quintero, Carlos Gerardo. "Comportement rhéologique et propriétés interfaciales des systèmes émulsionnés d'intérêt industriel : cas des émulsions pétrolières E/H." Paris 11, 2008. http://www.theses.fr/2008PA114835.
Повний текст джерелаRheological properties of crude oil-in-water emulsions studied, as well as the properties of the interface. Viscoelastic, plastic and flow behavior was studied. Viscosity as a function of phase ratio provides an exponential trend (Richardson’s Law). Crude oil has a very different rheological behaviour at temperatures upper or lower than 23°C, corresponding to paraffin’s precipitation point. The properties of concentrated emulsions can be modeled according Princen’s theories. The rheological behavior of the interface was characterized through measurements of the viscoelastic properties, using a drop oscillating rheometer. It was verified the formation of a gel at the interface according to the Law of Winter and Chambon. The crude oil composition and the volume fraction of the dispersed phase are very important factors to describe the rheological properties of these emulsions
Bondet, de la Bernardie Emmanuel. "Faisabilité d'un capteur utilisant le rayonnement micro-onde pour la mesure de concentrations dans un milieu polyphasique : application aux fluides pétroliers s'écoulant dans un tuyau." Paris 6, 2006. http://www.theses.fr/2006PA066149.
Повний текст джерелаColombel, Emilie. "Cristallisation et agglomération de particules d'hydrate de fréon dans une émulsion eau dans huile : étude expérimentale et modélisation." Phd thesis, Ecole Nationale Supérieure des Mines de Saint-Etienne, 2008. http://tel.archives-ouvertes.fr/tel-00372517.
Повний текст джерелаCette étude à pour but d'améliorer la compréhension de ce mécanisme d'agglomération, dans le cas d'une émulsion eau dans huile. Par conséquent, l'agglomération des particules de glace et d'hydrate est comparée. L'agglomération des particules de glace et d'hydrate de trichlorofluoromethane ou fréon (CCl3F) dispersées dans le xylène avec des asphaltènes comme tensioactif est choisie comme système modèle. Comme les hydrates de trichlorofluoromethane (CCl3F) sont stables à pression atmosphérique, ils permettent d'utiliser des techniques d'analyses sans être limité par les conditions de pression. La technique de Résonance Magnétique Nucléaire RMN est utilisée. La grande différence entre le temps de relaxation des solides et des liquides est utilisée afin de contrôler in situ le rapport entre la quantité d'entités (hydrogène ou fluor) solides et total en fonction du temps et des conditions contrôlées de cisaillement. Ainsi, une étude cinétique est réalisée, ce qui permet de connaître la quantité de glace ou d'hydrate formée ; La viscosité apparente du système, pendant la cristallisation et le bouchage, est également suivie grâce à des mesures rhéologiques afin de caractériser l'agglomération des particules. Pour compléter cette étude, des observations en microscopie optique avec une cellule thermostatée est utilisée afin d'obtenir des observations directes de l'agglomération. Cette approche expérimentale nous permet de discuter des différents mécanismes d'agglomération de la glace et de l'hydrate dans une phase hydrocarbure et de les modéliser.
Molle, Boris. "Etude des propriétés dynamiques de structures cellulaires formées dans un système eau/huile/surfactant/alcool." Université Joseph Fourier (Grenoble), 2000. http://www.theses.fr/2000GRE10249.
Повний текст джерелаWardhono, Endarto Yudo. "Optimization of concentrated W/O emulsions : stability, trapping and release of polysaccharides." Thesis, Compiègne, 2014. http://www.theses.fr/2014COMP1814/document.
Повний текст джерелаThis study is a part of the European project VEGEPHY (VEGEtale-PHYtosanitaire) to develop a product for the crop protection purposes. The product is a concentrated W/O emulsion trapping of a polysaccharide in the aqueous phase and rapeseed methyl ester oil as a continuous phase. Polysaccharide is used as a thickening adjuvant to modify the rheology properties of the water-based spray solution in order to reduce the drift of thespray. The objective of this study is to formulate concentrated W/O emulsions incorporation with the maximum amount of polysaccharide which show long stability (for over 2 years) and to study the release mechanism of polysaccharide in suitable conditions with a goal of an efficiency time less than 600 seconds.Concentrated W/O emulsions were realized by using a rotor stator system at room temperature. Aqueous phase containing polysaccharide and glycerol was dispersed into the stirred oil continuous phase where in a surfactant (lecithin and/or polyglycerol polyricinoleate, PGPR) has been previously dissolved. Stability tests were performed immediately after preparation and after ageing tests. Various parameters having an influence on thestability have been interpreted from DSC thermogram parallel with microscopic observation, laser diffraction granulometry and rheology measurement. DSC technique was used to study the emulsions by following the evolution of the droplet size versus time. Thermal behaviour of emulsions may be evaluated when they under gofreezing and melting in which the proportion of ice formed in the droplets may be calculated and their link with the evolution of the emulsion versus time. The release of the polysaccharide (CarboxyMethyl Cellulose, CMC)from the emulsion system is obtained by a two steps process : destabilization of the primary W/O emulsion by achemical product and dilution in water that gives an O/W emulsion containing the required concentration of polysaccharide. Destabilization was observed by following the evolution of dispersed droplets using DSC. Dilution process was assessed by measuring electrical conductivity of the water solution and a mathematical model to represent the kinetic release of CMC in water was proposed.The formulation and the stability of concentrated W/O emulsion has shown that DSC completed with granulometry and rheometry is an appropriate technique to study the emulsion characteristics. The study offreezing behaviour of emulsions show that the proportion of ice formed in the dispersed droplets during DSC test indicates good agreement between DSC measurements and thermodynamics calculation. The use of PGPRas surfactant and the introduction of glycerol in the formulation are beneficial to improve the long‐term stabilityof the emulsion. The optimum formulation of concentrated W/O emulsion was obtained containing : 3.5% w/wof CMC, 10% w/w of glycerol in 75% v/v of dispersed phase and 14% w/w of PGPR in the continuous phase. From the release study, an empirical model may be used to describe the released kinetic. The optimum amount of nonionic surfactant Cynthiorex PMH 1125 to break primary W/O emulsion was found at 10% w/w in the primary emulsion with NRe ≥ 4200 and T ≥ 20°C. Under practical field conditions, the minimum release time isthen around 200 seconds
Bonnet, Marie. "Libération contrôlée du magnésium par des émulsions doubles : impact des paramètres de formulation." Thesis, Bordeaux 1, 2008. http://www.theses.fr/2008BOR13669/document.
Повний текст джерелаDouble water-in-oil-in-water (W/O/W) emulsions are systems in which fat globules are dispersed in an aqueous continuous phase. They provide a compartmented structure that allows the encapsulation of hydrosoluble compounds in the internal aqueous droplets. Nevertheless, the application of multiple emulsions is limited by their thermodynamical instability and the possible diffusion of hydrosoluble matter from one aqueous phase to the other one through the oil layer. In this context, the influence of several formulation parameters (oil nature, hydrophilic emulsifier concentration, oil globule mass fraction, complexation of the encapsulated species) was investigated relatively to magnesium release. All the ingredients used were food grade to match pharmaceutical and food application requirements. Magnesium leakage occurred without film rupturing. A model based on diffusion was proposed in which the rate of release was determined by the permeation coefficient of magnesium across the oil phase, by magnesium chelation and by the osmotic pressure mismatch between the internal and external aqueous phases. The permeation coefficient depended on the chelating agent location and concentration but was poorly influenced by the osmotic pressure. Moreover, the permeation coefficient evolved with time, especially at high oil globule fractions
Dutoit, Agathe. "Approche multi-échelle des interactions entre inhibiteurs bactériens et milieux biphasiques." Electronic Thesis or Diss., Brest, 2024. http://www.theses.fr/2024BRES0035.
Повний текст джерелаThe use of natural antimicrobial compounds is common for controlling the growth of pathogenic or spoilage spore-forming bacteria in foods. Some of these compounds exhibit reduced inhibitory efficacy due to food matrices structural and physico-chemical complexity. The inhibitory properties of seven compounds were assessed on the growth of B. weihenstephanensis KBAB4 by modelling, and related to their physico-chemical characteristics. It appears that in an aqueous nutrient media, the inhibitory effectiveness of a compound is due to its lipophilicity, characterized by a higher dissociation at acidic pH or a higher partition coefficient (log P). The presence of a dispersed oil phase in a biphasic medium, an O/W emulsion, modulated the inhibitory activity of lipophilic fatty acids, highlighting the diffusivity of these acids between phases. Moreover, the lipophilic nature of caprylic acid allowed interactions with the emulsifiers used for system stabilization, thereby reducing its inhibitory activity. The inhibitory effectiveness of a hydrophilic acid (such as lactic acid) in these biphasic systems primarily depends on the pH of the medium but can also impact their structure. It was also shown that exposure to a model emulsion resulted in a loss of culturability of KBAB4 strain on BHA medium. This work has allowed to understand the interactions between spore-forming bacteria, inhibitory compounds and the components of an O/W emulsion, to optimize the formulation of healthy and safe food products
Raisin, Jonathan. "Electrocoalescence eau-huile Emulsions: Vers une efficacité critère." Phd thesis, Université de Grenoble, 2011. http://tel.archives-ouvertes.fr/tel-00647175.
Повний текст джерелаDallaire, Antonin. "Un modèle pour la séparation d'une émulsion huile-eau /." Thèse, Chicoutimi : Université du Québec à Chicoutimi, 1997. http://theses.uqac.ca.
Повний текст джерелаVernay, Clara. "Déstabilisation de nappes liquides d'émulsions diluées." Thesis, Montpellier, 2015. http://www.theses.fr/2015MONTS199/document.
Повний текст джерелаOne of the major environmental issues related to spraying of pesticides on cultivated crops is the drift phenomenon. Because of the wind, small droplets may drift away from the targeted crop and cause contamination. One way to reduce the drift is to control the spray drop size distribution and reduce the proportion of small drops. In this context, anti-drift additives have been developed, including dilute oil-in-water emulsions. Although being documented, the effects of oil-in-water emulsions on spray drop size distribution are not yet understood. The objective of this thesis is to determine the mechanisms at the origin of the changes of the spray drop size distribution for emulsion-based sprays.Agricultural spraying involves atomizing a liquid stream through a hydraulic nozzle. At the exit of the nozzle, a free liquid sheet is formed, which is subsequently destabilized into droplets. In order to elucidate the mechanisms causing the changes of the spray drop size distribution, we investigate the influence of emulsions on the destabilization mechanisms of liquid sheets. Model single-tear experiments based on the collision of one tear of liquid on a small solid target are used to produce and visualize liquid sheets with a fast camera. Upon impact, the tear flattens into a sheet radially expanding in the air bounded by a thicker rim. Different destabilization mechanisms of the sheet are observed depending on the fluid properties. A pure water sheet spreads out radially and then retracts due to the effect of surface tension. Simultaneously, the rim corrugates forming radial ligaments, which are subsequently destabilized into droplets. The destabilization mechanism is drastically modified when a dilute oil-in-water emulsion is used. Emulsion-based liquid sheets are destabilized through the nucleation of holes within the sheet that perforate the sheet during its expansion. The holes grow until they merge together and form a web of ligaments, which are then destabilized into drops.The physical-chemical parameters of the emulsion, such as emulsion concentration and emulsion droplet size distribution, are modified to rationalize their influence on the perforation mechanism. We correlate the size distribution of drops issued from conventional agricultural spray with the amount of perforation events in single-tear experiments, demonstrating that the single-tear experiment is an appropriate model experiment to investigate the physical mechanisms governing the spray drop size distribution of anti-drift formulations. We show that the relevant mechanism causing the increase of drops size in the emulsion-based spray is a perforation mechanism.To gain an understanding of the physical mechanisms at the origin of the perforation events, we develop an optical technique that allows the determination of the time and space-resolved thickness of the sheet. We find that the formation of a hole in the sheet is systematically preceded by a localized thinning of the liquid film. We show that the thinning results from the entering and Marangoni-driven spreading of emulsion oil droplet at the air/water interface. The localized thinning of the liquid film ultimately leads to the rupture of the film. We propose the perforation mechanism as a sequence of two necessary steps: the emulsion oil droplets (i) enter the air/water interface, and (ii) spread at the interface. We show that the formulation of the emulsion is a critical parameter to control the perforation. The addition of salt or amphiphilic copolymers can trigger or completely inhibit the perforation mechanism. We show that the entering of oil droplets at the air/water interface is the limiting step of the mechanism. Thin-film forces such as electrostatic or steric repulsion forces stabilize the thin film formed between the interface and the approaching oil droplets preventing the entering of oil droplets at the interface and so inhibit the perforation process
Potier, Lydie. "Etude par calorimétrie des changements d'état dans une émulsion multiple E/H/E : application aux.transferts de solvant entre les deux phases aqueuses." Compiègne, 1993. http://www.theses.fr/1993COMP664S.
Повний текст джерелаHahn, Oliver. "Stabilité au stockage d'émulsions huile dans eau diluées." Université Joseph Fourier (Grenoble), 2002. http://www.theses.fr/2002GRE10017.
Повний текст джерелаVernay, Clara. "Déstabilisation de nappes liquides d'émulsions diluées." Electronic Thesis or Diss., Montpellier, 2015. http://www.theses.fr/2015MONTS199.
Повний текст джерелаOne of the major environmental issues related to spraying of pesticides on cultivated crops is the drift phenomenon. Because of the wind, small droplets may drift away from the targeted crop and cause contamination. One way to reduce the drift is to control the spray drop size distribution and reduce the proportion of small drops. In this context, anti-drift additives have been developed, including dilute oil-in-water emulsions. Although being documented, the effects of oil-in-water emulsions on spray drop size distribution are not yet understood. The objective of this thesis is to determine the mechanisms at the origin of the changes of the spray drop size distribution for emulsion-based sprays.Agricultural spraying involves atomizing a liquid stream through a hydraulic nozzle. At the exit of the nozzle, a free liquid sheet is formed, which is subsequently destabilized into droplets. In order to elucidate the mechanisms causing the changes of the spray drop size distribution, we investigate the influence of emulsions on the destabilization mechanisms of liquid sheets. Model single-tear experiments based on the collision of one tear of liquid on a small solid target are used to produce and visualize liquid sheets with a fast camera. Upon impact, the tear flattens into a sheet radially expanding in the air bounded by a thicker rim. Different destabilization mechanisms of the sheet are observed depending on the fluid properties. A pure water sheet spreads out radially and then retracts due to the effect of surface tension. Simultaneously, the rim corrugates forming radial ligaments, which are subsequently destabilized into droplets. The destabilization mechanism is drastically modified when a dilute oil-in-water emulsion is used. Emulsion-based liquid sheets are destabilized through the nucleation of holes within the sheet that perforate the sheet during its expansion. The holes grow until they merge together and form a web of ligaments, which are then destabilized into drops.The physical-chemical parameters of the emulsion, such as emulsion concentration and emulsion droplet size distribution, are modified to rationalize their influence on the perforation mechanism. We correlate the size distribution of drops issued from conventional agricultural spray with the amount of perforation events in single-tear experiments, demonstrating that the single-tear experiment is an appropriate model experiment to investigate the physical mechanisms governing the spray drop size distribution of anti-drift formulations. We show that the relevant mechanism causing the increase of drops size in the emulsion-based spray is a perforation mechanism.To gain an understanding of the physical mechanisms at the origin of the perforation events, we develop an optical technique that allows the determination of the time and space-resolved thickness of the sheet. We find that the formation of a hole in the sheet is systematically preceded by a localized thinning of the liquid film. We show that the thinning results from the entering and Marangoni-driven spreading of emulsion oil droplet at the air/water interface. The localized thinning of the liquid film ultimately leads to the rupture of the film. We propose the perforation mechanism as a sequence of two necessary steps: the emulsion oil droplets (i) enter the air/water interface, and (ii) spread at the interface. We show that the formulation of the emulsion is a critical parameter to control the perforation. The addition of salt or amphiphilic copolymers can trigger or completely inhibit the perforation mechanism. We show that the entering of oil droplets at the air/water interface is the limiting step of the mechanism. Thin-film forces such as electrostatic or steric repulsion forces stabilize the thin film formed between the interface and the approaching oil droplets preventing the entering of oil droplets at the interface and so inhibit the perforation process
Moha, Ouchane Mustapha. "Phénomene de percolation dans les microémulsions eau/AOT/huile." Pau, 1987. http://www.theses.fr/1987PAUU3019.
Повний текст джерелаMoha-Ouchane, Mustapha. "Phénomène de percolation dans les microémulsions eau/aot/huile." Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb37608047z.
Повний текст джерелаOUCHENE, MAKRIA AMINA. "Ecoulements cisailles et elongationnels d'emulsions concentrees huile/eau. Rheometrie et gonflement de jet. Application aux emulsions alimentaires." Paris 7, 1995. http://www.theses.fr/1995PA077239.
Повний текст джерелаKeromnes, Hélène Billon Aurélie. "Formulation d'une émulsion Eau dans Huile avec des ingrédients naturels." [S.l.] : [s.n.], 2008. http://castore.univ-nantes.fr/castore/GetOAIRef?idDoc=33051.
Повний текст джерелаRAYNAL, ROHAN SYLVIE. "Emulsions multiples eau/huile/eau encapsulant du mgso4 : etude des transferts de matiere a temperature ambiante et subambiante par analyse enthalpique differentielle, rheologie et conductimetrie." Paris 11, 1996. http://www.theses.fr/1996PA114807.
Повний текст джерелаPairoys, Fabrice. "Étude expérimentale et numérique des écoulements eau/huile dans les milieux poreux vacuolaires." Bordeaux 1, 2004. http://www.theses.fr/2004BOR12850.
Повний текст джерелаVugular porous media are found in many reservoirs especially those constituted of carbonate rocks where large cavities (called vugs) resulting from complex diagenetic processes are embedded in the porous matrix. Due to their structure, these porous materials have special transport properties and optimization of oil recovery from such reservoirs requires a good description of two-phase -oil and water- flow. Model vugular samples were obtained from a sandstone core, representing the continuum and homogeneous porous matrix through which cylindrical holes, representing the vugs, were drilled. Transparent windows, placed in front of the vugs allow a direct observation of the two-phase distribution and the evolution during flow. Due to the configuration, the flow is two-dimensional and saturation maps were obtained from local saturation measurement in the porous matrix using a ?-ray attenuation technique. During drainage and imbibition cycles, saturation, pressure and recovery measurements are performed. Using different density contrasts between oil and brine, the relative effect of viscous and gravity forces was investigated. Two-dimensional numerical simulations were performed on the experimental configuration using an industrial software. In our configuration, a heterogeneous generalized Darcy's model is tested. The vugular core was represented by a two-region medium corresponding to the matrix and vugs respectively. Petrophysical properties of the porous matrix were assigned by fitting experimental two-phase flow results obtained on a separate but similar homogeneous core -without vugs. In the region corresponding to the vugs, a zero capillary pressure was used while different sets of oil and water relative permeabilities were tested for comparison of pressure and saturation evolution on the vugular core with experimental data
Jada, Amane. "Etude de la structure et de la dynamique de microemulsions eau dans huile." Université Louis Pasteur (Strasbourg) (1971-2008), 1988. http://www.theses.fr/1988STR13101.
Повний текст джерелаJada, Amane. "Etude de la structure et de la dynamique de microémulsions eau dans huile." Grenoble 2 : ANRT, 1988. http://catalogue.bnf.fr/ark:/12148/cb376144506.
Повний текст джерелаHURUGUEN, JEAN-PIERRE. "Influence d'une proteine sur les phenomenes de percolation en micro-emulsions eau dans l'huile." Paris 6, 1991. http://www.theses.fr/1991PA066163.
Повний текст джерелаColombel, Emilie. "Cristallisation et agglomération de particules d'hydrate de fréon dans une émulsion eau dans huile. Etude expérimentale et modélisation." Saint-Etienne, EMSE, 2008. http://tel.archives-ouvertes.fr/tel-00372517.
Повний текст джерелаThis work deals with the problem of pipeline blockage by gas hydrates during oil production. Gas hydrates are crystals resulting from water and gas molecules association under high pressure and low temperature conditions. Such thermodynamical conditions are generally encountered in oil production, particularly for deep offshore fields or cold areas. Due to agglomeration process, hydrate occurrence leads to plug formation. The main objective of this study is to improve our understanding in the mecanisms involved in the agglomeration process, particularly for water in oil emulsions. Results have allowed us to supply a theorical model of agglomeration. A model system of Ice and Freon hydrates dispersed in xylene with asphaltenes as surfactant is used. As Freon hydrates form under atmospheric pressure at low temperature, it allows us to apply different techniques without being limited by pressure conditions. The Nuclear Magnetic Resonance (NMR) technique is mainly used. It makes the measurement of the ratio between solid hydrogene or fluorine in ice or hydrate and total hydrogen or fluorine in the sample possible - enabling to know the quantity of formed ice or hydrates. Thus, a kinetic study is realized, enabled to know the quantity of ice and hydrate formed. To complete this work, optical microscopy with cooling cell is used to get direct observations of agglomeration. The rheometry technique is also used. It enables us to study the evolution of the apparent viscosity of the system during ice or hydrate formation and plugging. These techniques can also be applied to study real systems like methane hydrates in crude oils under field conditions. Moreover, an interpretation, which couples rheology, crystallisation and agglomeration, is studied and leads to a model
Grenier, Nicolas. "Modélisation numérique par la méthode SPH de la séparation eau-huile dans les séparateurs gravitaires." Phd thesis, Nantes, 2009. http://tel.archives-ouvertes.fr/tel-00664668.
Повний текст джерелаGrenier, Nicolas. "Modélisation numérique par la méthode SPH de la séparation eau-huile dans les séparateurs gravitaires." Phd thesis, Nantes, 2009. http://www.theses.fr/2009NANT2038.
Повний текст джерелаIn oil extraction industry, efficiency of water-oil separators for offshore production is crucial. The aim of this work is to develop numerical tools able to model such systems in operation. The physical phenomena involved are mainly : the presence of an interface between two immiscible fluids, the viscosity of these fluids, and surface tension effects. Corresponding physical and numerical models have been implemented in the frame of the SPH (Smoothed Particle Hydrodynamics) numerical method developed at L. M. F. . The main features of SPH are : particle-based method (mesh-free), weakly-compressible approach and explicit resolution. To improve two-phase flows modeling, classical formulation of SPH has been extended by two different approaches, developed simultaneously. Each of these has been validated separately. Additional physical effects have been implemented using shared models which validations have been performed on several test cases such as Poiseuille flows, Rayleigh-Taylor instabilities, flooding or bubble evolutions in liquids. The latter has allowed comparison to the design tools used in the SAIMPEM S. A. Engineering process, through the validation versus Stoke's law. Eventually, the method capabilities are illustrated on the water-oil separation in a separator of simplified geometry
Le, Ba Hung. "Formation et agglomération de particules d'hydrate de gaz dans une émulsion eau dans huile : Etude expérimentale et modélisation." Phd thesis, Ecole Nationale Supérieure des Mines de Saint-Etienne, 2009. http://tel.archives-ouvertes.fr/tel-00475562.
Повний текст джерелаLe, Goff-Bucas Gwénaelle. "Le comportement des polluants flottants en cas de déversement accidentel en eau de mer." Paris 6, 2002. https://tel.archives-ouvertes.fr/tel-00120323.
Повний текст джерелаKhalil, Abir. "Étude expérimentale d'un procédé de cristallisation en émulsion huile dans eau : application au distéarate d'éthylène glycol." Phd thesis, Université Claude Bernard - Lyon I, 2011. http://tel.archives-ouvertes.fr/tel-00862852.
Повний текст джерелаKhalil, Abir. "Étude expérimentale d’un procédé de cristallisation en émulsion huile dans eau : application au distéarate d’éthylène glycol." Thesis, Lyon 1, 2011. http://www.theses.fr/2011LYO10272/document.
Повний текст джерелаThe aim was to study the crystallization in emulsion process of a hydrophobic cosmetic ingredient (EGDS). The emulsification of the molten EGDS in a continuous phase with the use of an emulsifier in order to obtain a stable droplet size distribution (DSD) is the first stage. The crystallization upon cooling is the second stage. Two optical probes were developed to allow the in situ video monitoring of each stage of the process in real time. From the video sequences recorded the measurement of the DSD was carried out automatically, and by an operator for the PSD. The growth of crystals in motionless droplets was observed under microscope thanks to a thermostated well. The specific power input of stirring was the main parameter acting on the reduction of DSD owing to its action on the droplet break-up mechanism. The surfactant concentration was a parameter of secondary relevance on the DSD (coalescence and stability). The use of a flat blade propeller instead of a Rushton turbine was preferable for the production of a narrower DSD. Finally the time required to reach equilibrium was found higher by a factor of 3-4 than predicted in the literature. It was shown that the droplets crystallized very progressively during cooling, from the biggest to the smallest droplets. With the experimental conditions, one drop gave birth to one particle. The primary nucleation rate was obtained from the analysis of the temporal evolution of the DSD with the hypothesis of a mononuclear mechanism in each droplet. The nature of the mechanism seems to be heterogeneous. Nevertheless its localization in the droplet volume or at the inner interfacial surface was not possible
Zanota, Marie-Line. "Formation d'hydrates dans les systèmes quaternaires eau/THF/huile/tensioactif(s) : Effet anti-agglomérant des tensio-actifs." Pau, 2001. http://www.theses.fr/2001PAUU3033.
Повний текст джерелаDeguillard, Estelle. "Simulations de Dynamique Particulaire Dissipative pour le calcul de tension interfaciale dans des systèmes eau/tensioactif/huile." Thesis, Paris 11, 2014. http://www.theses.fr/2014PA112288/document.
Повний текст джерелаThe interfacial tension is a physical-chemical property that numerous industrial areas have an interest of especially the petroleum industry. This property is one of the many which helps to optimize production wells' rate of return. Measuring that property in reservoir's conditions (high pressure and temperature) is highly difficult and led to study water/surfactant/oil systems using molecular modeling. The difficulty to measure that specific physical-chemical property linked to the pressure and temperature conditions in the reservoirs led the scientists to study water/surfactant/oil systems using molecular modeling. This thesis establishes that the Dissipative Particle Dynamics (DPD) is able to study water/surfactant/oil systems. The study of the effect of the variation of the harmonic force's parameters, namely the force constant K and the equilibrium distance r0, demonstrated that their variation can heavily influence the interfacial tension computation. Actually, a subtle balance exists between the intra and inter-molecular interactions, which influences the local structure of the surfactants at the oil-water interface, modifies the interfacial tension and influences the interface stability. It was demonstrated that DPD reproduces the variation of interfacial tension with the bulk surfactant concentration and the effect of the variation of hydrophobicity of models of un-charged surfactants on interfacial tension by mean of their coefficient partition. We established a method to properly study systems containing interfaces where interfacial tension is computed. Prospective work showed that DPD was a good tool to study microscopic phenomenon which can be observed macroscopically like the Ostwald ripening in oil in water emulsions. This is a first step before studying others systems of interest for the petroleum industry such as oil/water emulsion or the adsorption of oil droplets on rock wall
Ysambertt, Soto Fredy J. "Etude des mélanges de surfactifs dans des systèmes microémulsion/eau/huile présentant un partage préférentiel des différentes espèces." Pau, 1997. http://www.theses.fr/1997PAUU3012.
Повний текст джерелаChebab, Mohamed Bechir. "Formulation et caractérisation par DSC de systèmes émulsionnés Eau-dans-Huile, à base d'argiles et d'huiles d'olive tunisiennes." Compiègne, 2009. http://www.theses.fr/2009COMP1838.
Повний текст джерелаSirvente, Helga. "Fonctionnalités des fractions du jaune d'oeuf dans les émulsions alimentaires huile-dans-eau allégées en matière grasse : impact des différents niveaux de structuration." Nantes, 2007. http://www.theses.fr/2007NANT2160.
Повний текст джерелаMayonnaise is an egg yolk-stabilized emulsion. The decrease of oil quantity in light mayonnaises causes problems of stability and texture resolved by additives. This work aimed at understanding the behaviour of egg yolk constituents in the formation and stabilisation of mayonnaise and at formulating light mayonnaises without additives close to traditional mayonnaises. Physico-chemical, interfacial and emulsifying properties of plasma and granules have been characterized. The impact of thermomechanical treatments on structuring and functionalization of fractions dispersions has been studied. Model mayonnaises with low-fat content has been prepared incorporating fractions at different homogenization stages or aerating after emulsification. Plasma constituents are better emulsifiers than those of granules whatever the pH and the ionic strength. At acidic pH, granules in aggregates state are worse emulsifiers than at neutral pH. High pressures cause aggregation of plasma proteins but have little effect on emulsifying properties. Nevertheless, they modify the structure and the emulsifying properties of granules. Incorporation of granules before the homogenization stage increases the firmness of model mayonnaises. Aeration of mayonnaises confers stability and satisfying texture of granules-based mayonnaises. Contrary to dairy foams which are stabilized by partially crystallized fat, these mayonnaises would be stabilized by granules aggregates situated at the oil droplet surface
Sacca, Linda. "Etude par analyse calorimétrique différentielle de la caractérisation et de l'évolution d'émulsions eau dans huile en vue d'une étude en micropesanteur." Compiègne, 2007. http://www.theses.fr/2007COMP1674.
Повний текст джерелаTo study the mechanisms of emulsion destabilization under microgravity conditions, we proposed a technique based on the correlation between the state of water dispersion and the temperature of crystallization detected by DSC. This technique consists in submitting an emulsion sample to a cooling and heating cycle. This test performed at successive time : intervals allows to follow the evolution of the emulsion maintained at ambient temperature. By performing successive cycles on the same sample or after storage at high temperature, we could accelerate the emulsion ageing and see the effect of it. These studies were made on simple and mixed W/O emulsions stabilized by surfactant in variable quantity. Preliminary results obtained on emulsions stabilized by partic1es (silica powder R711) are described. These results show that it is possible to prepare emulsions with these particles alone. Moreover, these emulsions have a different behaviour during storage and following an accelerated ageing
Alliod, Océane. "Development and valorization of a membrane emulsification process for the production of nanoemulsions." Thesis, Lyon, 2018. http://www.theses.fr/2018LYSE1264/document.
Повний текст джерелаNanoemulsions are interesting carriers for applications such as cosmetics, pharmaceutical and food. They are produced usually by low or high energy techniques. In this work, a process involving moderate pressure, premix membrane emulsification (PME) was proposed as an alternative. Oil-in-water (O/W) and water-in-oil (W/O) nanoemulsions were produced with a pilot scale set-up composed of a controlled high pressure syringe pump and Shirasu Porous Glass (SPG) membrane. First, the influence of process and composition parameters on droplet sizes and pressures was extensively studied with model compositions to optimize the production. Thus, nanoemulsions down to 260 nm for O/W and around 600 nm for W/O were successfully produced. Then, the set-up was used to produce nanoemulsions of specific compositions: O/W and W/O nanoemulsions stabilized with polypeptidic surfactants and O/W nanoemulsions suitable for injection. Finally, the set-up developed was compared to two traditional high energy processes, microfludizer and ultrasound in terms of droplet size and active preservation. No real difference between the three processes was seen on active preservation with the model active chosen. However, regarding droplet size, PME produced monodispersed droplets of 335 nm compared to the other processes which produced nanoemulsions of around 150 nm but with the presence of micron size droplets detected by laser diffraction and optical microscopy. Therefore, PME nanoemulsions are also suitable for parenterals applications with no additional filtration step required
Luong, Anh Tuan. "Influence de la concentration en sel sur la formation de phases solides dans les émulsions eau dans huile concentrées : application à l'étude des hydrates de CCl3F." Compiègne, 2008. http://www.theses.fr/2008COMP1773.
Повний текст джерелаThis work concerns the study of formation of solid in water-rich (60%) water-in-oil (W/O) emulsions. Particular attention is given to the formation and dissociation of CCl3F hydrate, which is a good model of natural gas hydrates. The dissertation is divided into three main chapters: the first chapter deals with the mechanisms of formation of solid phases, starting from a pure substance (water) or from an aqueous salt solution. The second chapter focuses on the characterization of concentrated W/O emulsions by differential scanning calorimetry (DSC), which was found to be successful when dealing with opaque emulsions. The influence of salt concentration on the formation of ice in emulsion was also investigated. The last chapter is devoted to the formation and dissociation of CCl3F hydrate in emulsion by coupling DSC and X-ray diffraction. Similarities in the mechanisms of formation of ice and CCl3F hydrate were evidenced. Kinetics at constant temperature revealed a delay in crystal formation for both systems, which is larger when the temperature is closer to the equilibrium temperature, in accordance with classical theories of nucleation. In presence of salt, the behaviour of both solids, ice and clathrate hydrate, is similar. X-ray diffraction experiments enabled us to differentiate clearly the hydrate from ice and showed that the hydrate could be formed alone, without the presence of ice
Le, Follotec Amandine. "Déstabilisation des émulsions pétrolières par des polymères triblocs siliconés : relation structure - propriétés interfaciales." Compiègne, 2009. http://www.theses.fr/2009COMP1817.
Повний текст джерелаWater-in-crude oil emulsions are often formed during crude oil exploitation. For oil refining purpose, chemical demulsifiers are commonly used. In this work, five triblock silicone copolymers with various demulsifying capacities are studied. Results obtained at plane interfaces such as air-water and oil-water do not allow clear distinction between the molecules. Study of curved interfaces reveals that efficient molecules which can destabilise water-in-crude-oil emulsions indeed stabilise oil-in-water emulsions. On the contrary, inefficient molecules stabilise water-in-oil emulsions. Spontaneous curvature of molecules has been investigated by Small Angle Scattering. The following interpretation is therefore envisaged: for two water drops to coalesce the oil lamella between them should break, i. E. Small but highly curved hole must nucleate in it. On the one hand, efficient molecules should favour the hole nucleation and favour the coalescence of water droplets in crude oil emulsions. On the other hand, inefficient molecules inhibit the hole formation and prevent the coalescence of water droplets
FIDEL-DUFOUR, Annie. "Influence d'additifs anti-agglomérants sur l'agrégation et les propriétés de transport des hydrates de méthane cristallisant dans des émulsions eau/dodécane." Phd thesis, Ecole Nationale Supérieure des Mines de Saint-Etienne, 2004. http://tel.archives-ouvertes.fr/tel-00010236.
Повний текст джерелаCette thèse participe à la modélisation des écoulements après formation d'hydrates. Il ne s'agit donc pas d'empêcher la cristallisation mais de s'intéresser à la rhéologie de l'écoulement après formation de cristaux. L'objectif à long terme est d'identifier l'origine de la transportabilité des coulis d'hydrates sous l'influence d'additifs dits « anti-agglomérants ».
Les mécanismes de cristallisation sont en effet très souvent couplés : germination, croissance, agglomération, attrition... La compréhension du mécanisme d'action d'un additif est donc une tache complexe, d'autant plus que la cristallisation est intimement liée au système physique dans lequel elle se développe. Les études cherchant à identifier les mécanismes de cristallisation, pour ensuite comprendre les effets d'additifs ont toutes (ou pratiquement) été effectuées dans des réacteurs fermés et systèmes simples (eau/gaz) (Herri (1996), Pic (2000)...). A l'inverse, des tests de validation d'additifs ont été effectués sur des boucles pilotes représentant un écoulement réel, donc complexe.
Notre travail se situe donc à mi-chemin des deux approches précédentes. Il s'agit de se rapprocher des conditions géométriques d'un écoulement pétrolier (boucle pilote) tout en conservant un système simple (eau/dodécane) avec pour objectif sur le long terme d'identifier le couplage : géométrie/cristallisation/influence des additifs.
Le dispositif expérimental (hauteur 12 m, largeur 3 m, longueur 6 m) réalisé dans le cadre de cette thèse est une boucle pilote de circulation reproduisant certaines conditions de l'écoulement d'un fluide pétrolier (émulsion eau dans huile) dans une conduite sous-marine, c'est-à-dire sous forte pression [1-10 MPa] et faible température [0-10 °C]. Les différentes parties de cet instrument sont :
· Le serpentin s'enroulant sur 3 niveaux,
· Le tube montant, plus souvent désigné dans sa terminologie anglosaxone par « riser ». A la base de ce tube est injecté du méthane de façon à alléger la colonne de fluide pour créer un effet ascenseur (terminologie anglosaxone « gaslift »).
· Le séparateur situé au sommet du riser sépare par gravité la partie gaz, de la partie liquide (eau, huile) qui redescend dans un tube parallèle au riser vers la boucle de circulation.
· Le système de recompression des gaz récupère les gaz du séparateur pour les réinjecter au bas du riser après augmentation de la pression.
Ce système expérimental est composé in fine de deux boucles circulant sur elles-mêmes : une boucle liquide et une boucle gaz. Ces deux boucles partagent une section commune composée du riser et du séparateur.
Ce dispositif a permis de réaliser des études rhéologiques sur la phase continue seule (dodécane) en fonction de la pression de méthane et sur des émulsions contenant diverses teneurs en eau et en additifs. Des études concernant la cristallisation des hydrates de méthane au sein des émulsions ont été réalisées en considérant l'influence de la teneur en eau puis celle de la teneur en additif sur la viscosité apparente des dispersions ainsi formées. Nous proposons enfin une modélisation reliant la cristallisation au comportement rhéologique.
Butstraen, Chloé. "Optimisation de l’encapsulation de produits lipophiles via l’utilisation des émulsions de Pickering et des procédés sol-gel pour la fonctionnalisation de textiles." Thesis, Lille 1, 2015. http://www.theses.fr/2015LIL10111/document.
Повний текст джерелаThis study was performed as a part of FOMOTEX collaborative research project (functionalization foams and Innovative textiles). The purpose is the development of an encapsulation process of lipophilic product as flame retardants for the functionalization of textiles. To allow the bonding to textile fibers, their preparation is based on the synthesis of a double wall particles, the first wall having a protective role and the second, melt, allowing the linkage on the textile support during processing . This thesis focuses on the selection of materials to prepare the particles, on their processing and on the understanding of the synthesis mechanisms of particle and on their characterization to enable the optimization of synthesis parameters. A first part deals with the use of silica nanoparticles to extend the stabilization of the emulsion, called Pickering emulsion, and to limit the exudation phenomena of the active substance. Their influence on the encapsulation by sol-gel processes is studied. A second part concerns the study of the influence of formulation and synthesis parameters on micropaticules characteristics and the optimization of the encapsulation by sol-gel processes. Finally, in a last part, the concept of double wall microcoencapsulation, the outer membrane allowing bonding to textile fibers, has been validated
Maurer, Olivier. "Etude de la distribution des espèces soufrées et de la production d'hydrogène sulfuré dans les stockages de gaz naturel en aquifères." Marne-la-vallée, ENPC, 1992. http://www.theses.fr/1992ENPC9230.
Повний текст джерелаObservations of natural gas quality withdrawn from natural gas aquifer starages often shows that desulfuration is needed but that hydrogen sulfid production is marginal compared to volumes. After adopting a geochamical and pluridisciplinal approach, realising an analytical program and performing specifical tools development, we propose a hydrogen sulfid formation model. Based on gas-water equilibrium and dissolved sulfur production, this model oppses a central area, desulfurized by acid but non-sulfurous gas injection to a peripheric area, enriched in sulfurous water and where mixing phenomenons are important. The major geochemical observation consists in storage water carbonatation, methane oxidation. Active parameters in the hydrogen sulfid production are essentially sulfurs, sulfates and alkalin ions water concentrations,, carbon dioxide and carbon oxysulfu gas content, solid carbonates and ferrous iron wzater saturations, sulfate-reducing, methanogenic and methanotrophic bacterial activities, as well as acid, temperature, pression and redox conditions in the medium. An isotopic synthesis also shows that jurassic sulfates of the parisian Basin are affiliated to a triasic sulfate, that dissolved natural sulfurs originate from the fossile bioreduction of those sulfates, and how dissolved carbonates in the gas exploited areas are carbon 13 enriched
Sadtler, Véronique. "Emulsions inverses eau-dans-fluorocarbure pour le transport de medicaments par la voie pulmonaire. Stabilisation par des tensioactifs fluores : synthese et physico-chimie des dimorpholinophosphates de (f-alkyl)alkyle." Nice, 1997. http://www.theses.fr/1997NICE5145.
Повний текст джерелаChatenay, Didier. "Diffusion, solubilisation et propriétés interfaciaux dans les solutions isotropes d'amphiphiles." Paris 11, 1987. http://www.theses.fr/1987PA112297.
Повний текст джерелаEl, Bari Mounir. "Séchage des cartons présents dans les transformateurs de puissance." Grenoble INPG, 1994. http://www.theses.fr/1994INPG0085.
Повний текст джерелаChijika, Kongolo. "Les techniques lustrales dans les écrits bibliques." Doctoral thesis, Université Laval, 1999. http://hdl.handle.net/20.500.11794/40573.
Повний текст джерелаGuzun-Cojocaru, Tatiana. "Peroxydation des lipides émulsionnés et transfert d'ions fer à l'interface huile / eau stabilisée par des protéines de lait : influence des résidus phosphates et de la stabilité du chélate de fer." Thesis, Dijon, 2010. http://www.theses.fr/2010DIJOS012/document.
Повний текст джерелаIron incorporated into food systems induces oxidation and precipitation. The consequences are a reduced bioavailability and a modification of other food flavor. The iron chelates such as Fe-bisglycinate and Fe-EDTA represent a possibility to avoid side effects, since the iron is protected. The inertety of Fe bisglycinate and NaFe EDTA for lipid peroxidation has been verified in oil-in-water emulsion models stabilized by sodium caseinate or by β lactoglobulin through the following studies: i/ increase of primary and secondary products of oxidation, ii/ change of the properties of the oil/water interface (tension and interfacial rheology), iii/ the stability of the chelate iron (Fe-bisglycinate) in the aqueous phase with β lactoglobulin at different pH (pH 2, 3.5 and 6.5). The oil/water interface stabilized by proteins with phosphate groups has induced peroxidation, which was not observed with proteins containing no phosphate residue. These results demonstrate also that the type of iron salts plays a crucial role in the oxidative stability of emulsions. The ability of the complex to retain iron ion and to avoid “free” ferrous ion is the first important factor to be controlled. The affinity of milk proteins to bind these free iron ions is the second factor that controls the transfer to oil/water interface. To sum up, the competition for iron ions between functional groups of protein and salt counter ions (glycinate, sulfate or EDTA) governs the oxidation state of the system in neutral conditions. In acidic medium, the oxidation is mainly governed by the stability of the complex and the possibility to free iron in bulk