WorldCat Identities

École doctorale SIMPPé - Sciences et ingénierie des molécules, des produits, des procédés, et de l'énergie (Lorraine)

Overview
Works: 112 works in 112 publications in 2 languages and 112 library holdings
Roles: Other
Publication Timeline
.
Most widely held works by des produits, des procédés, et de l'énergie (Lorraine) École doctorale SIMPPé - Sciences et ingénierie des molécules
Modification chimique des extractibles de bois : application à la protection du bois et des matériaux métalliques by Wissem Sahmim( )

1 edition published in 2018 in French and held by 1 WorldCat member library worldwide

Within the framework of this thesis, we are interested in the design, synthesis and characterization of the physicochemical properties of lipophilic derivatives of wood extractives. We have thus considered modifying the structure of three flavonoids whose resource is important from different wood species: catechin, mesquitol and naringenin to incorporate additional functionalities. The applications reported here mainly deal with the protection of materials like wood and corrodible metals. With respect to wood preservation, it seems possible to consider different strategies to inhibit the wood degradation related to fungi on wood. Impregnation of antioxidant compounds such as lipophilic polyphenols on wood can limit the effects of radicals or other oxidants used and generated by rots. The second intended application is the protection of metallic materials. Indeed, the use of natural antioxidants as a corrosion inhibitor replace inorganic inhibitors or organic molecules (polyamines, imidazole...), because their production is expensive and toxic. The grafting of a hydrophobic hydrocarbon chain on polyphenols which have antioxidant properties allows the formation of protective films on the material
Methodological approach for the sustainable design of structured chemical products during early design stages by Juliana Serna Rodas( )

1 edition published in 2018 in English and held by 1 WorldCat member library worldwide

En raison de la compétitivité dans le marché des produits chimiques et la demande croissante pour les produits de qualité, l'industrie et l'académie sont à la recherche de nouvelles méthodes pour la conception des produits chimiques. Par conséquent, cette étude propose une approche méthodologique pour faciliter la prise de décisions dans la conception de produits de type émulsion. Les caractéristiques de la méthodologie proposée sont les suivantes: elle propose des méthodes pour l'analyse des besoins de consommateurs, la génération d'idées pour la conception du produit et la sélection du meilleur produit, en prenant en compte la nature multi-variée du problème de conception avec l'intégration de la notion de durabilité dans le processus de conception. La méthodologie comporte trois étapes de conception: Étape de besoins, étape de génération d'idées et étape de sélection d'idées. Dans la première étape, les besoins sont analysés et classifiés en fonction de leur impact sur la satisfaction du client. Ensuite, ils sont traduits aux spécifications du produit avec l'aide des experts et des clients. Les informations de saisie correspondent aux besoins des clients et celles de sortie correspondent aux spécifications du produit, c'est-à-dire des caractéristiques du produit qui peuvent être évaluées. Également, deux méthodes sont utilisées: le modèle de kano et la méthode QFD (Déploiement des Fonctions Qualités). Dans la seconde étape, les produits répondant aux spécifications sont conçus en suivant une démarche en trois phases: 1) le problème de conception est divisé selon un groupe défini de sous-problèmes généraux. 2) Chaque sous-problème est connecté à un groupe de stratégies de solution selon une première matrice de décision prédéfinie. 3) Les stratégies de solution sont connectées avec des ingrédients et des conditions opératoires selon une deuxième matrice de décision. Cette démarche est faite en utilisant deux matrices de décision développées dans cette recherche sur la base de la connaissance de science d'émulsion, ainsi que sur des connaissances des experts. Dans la troisième étape, les alternatives de produit sont évaluées selon le cahier de spécifications définis dans la première étape et les indicateurs de durabilité appropriés. Ces indicateurs sont utilisés pour évaluer et classer les alternatives de produit selon un indice de développement durable global. Pour développer cette étape un ensemble d'indicateurs évaluant la dimension économique, environnementale et sociale de produits est choisi et ils sont intégrés par la mise en oeuvre d'une méthode d'analyse de multi-critère. Finalement, afin d'illustrer la méthodologie, une étude de cas est développée: la conception d'une crème hydratante
Écoulements polyphasiques et phénomènes interfaciaux à multi échelles by Qindan Zhang( )

1 edition published in 2020 in English and held by 1 WorldCat member library worldwide

Multiphase flows and interfacial phenomena are widely involved in the natural world, our daily life, and numerous industrial processes. By employing three different techniques including a high-speed camera, an ultra-high-speed Direct Current (DC) electrical device, and a high-speed micro-Particle Image Velocimetry (micro-PIV), the multiphase flows and interfacial phenomena at multiscale were investigated experimentally by both passive and active methods. The flow behaviors of the elastic non-Newtonian two-phase flow in both T-junction and flow-focusing devices were investigated. The fluid elasticity affected the dynamics of droplet formation, stretching and breakup. During the droplet formation, the peculiar beads-on-string flow was observed. The influences of the fluid elasticity on the minimum neck width, the maximum length of the dispersed thread and the droplet size were studied. The predicting models for the droplet size were optimized by introducing the dimensionless parameters to characterize the fluid elasticity. For the stretching and breakup of elastic droplets, the influences of elasticity on the transition from droplet stretching to breakup, the dynamics of droplet stretching and breakup as well as the size ratio of the daughter droplets were also investigated. The power-law models were proposed to predict the maximum stretching length. Subsequently, the initial coalescence of a pendant drop at a liquid surface and the initial spreading on a solid surface were investigated. The ultra-high-speed DC electrical device with the sampling speed of 1.25×106 Hz allows to monitoring the dynamics of coalescence and spreading within 10 µs. The coalescing width expands linearly with time in the inertially limited viscous regime and follows a power law in the inertial regime. The evolutions of the velocity fields during the initial coalescence and spreading were measured and computed by the high-speed micro-PIV with a capturing rate up to 5000 velocity fields per second, revealing the transformation of surface energy to kinetic energy. Besides, the consecutive electrical peaks with a regular interval of 20 ms were observed during the filament thinning of the polymer liquid neck. In addition, the active manipulation of the ferrofluid drop was realized by introducing an external magnetic field. Evident deformations of both the pendant ferrofluid drop and the bulk surface were observed prior to the contact even in the absence of a magnetic field. The exponential laws were proposed to predict the increasing coalescing width with time and the decreasing maximum coalescing width with the magnetic field. A high-speed micro-PIV technique was employed with a transparent model fluid to reveal the flow fields during the ferrofluid drop coalescence. The self-sustained coalescence-breakup cycles of ferrofluid drops were observed for the first time. The exponential model was proposed to predict the increasing periodic frequency with the applied magnetic field
Traitement de minerais de fer par lixiviation alcaline suivi de leur électrolyse en milieu alcalin by Vincent Feynerol( )

1 edition published in 2018 in French and held by 1 WorldCat member library worldwide

Un procédé innovant de production de fer par électrolyse d'une suspension d'oxydes de fer en milieu alcalin concentré est développé au centre de recherche d'ArcelorMittal de Maizières-lès-Metz. Ce procédé s'il atteignait la maturité industrielle permettrait de réduire significativement les émissions de dioxyde de carbone associées à l'industrie sidérurgique, en remplaçant le carbone utilisé comme agent réducteur dans les hauts-fourneaux par de l'électricité. Bien que ce procédé permette la production de fer à partir d'hématite commerciale (Fe2O3) à une densité de courant de l'ordre de 1000 A.m-2 avec une efficacité faradique supérieure à 80%, une dégradation des performances est systématiquement constatée lors de l'électrolyse de minerais de fer. Les impuretés majoritaires de ces minerais sont les oxydes et hydroxydes d'aluminium et de silicium, des composés solubles dans la soude concentrée. Ces composés pourraient donc être à l'origine de la baisse de réactivité observée lors de l'alimentation du procédé par des minerais de fer. Ainsi afin de tenter d'améliorer les performances de l'électrolyse alcaline à partir de minerais, des traitements de lixiviation alcaline sur un minerai défini ont été effectués dans cette thèse. La réactivité des minerais avant et après traitement a été comparée par chronoampérométrie. Bien que suite à l'élimination de ses composés alumineux, le minerai traité ait vu son rendement faradique réhaussé à environ 80% pour une valeur avant pré-traitement de 65%, sa densité de courant est restée deux fois moins élevée que celle de l'hématite pour une même tension électrique appliquée. Des expériences d'ajout d'ions aluminates et d'ions silicates lors de l'électrolyse d'hématite pure n'ont de plus eu pratiquement aucun effet indésirable sur son électrolyse. Les diverses expériences conduites dans cette thèse laissent supposer que les impuretés traitées n'ont que peu d'influence sur la réactivité des minerais. Le procédé est en revanche très sensible à la granulométrie des particules de minerais. Par ailleurs de forts phénomènes d'agglomération, qui n'ont pas lieu avec les oxydes de fer purs, ont été constatés lors de mesure de granulométrie du minerai étudié. Ainsi les expériences réalisées laissent supposer qu'un autre phénomène, probablement lié à la granulométrie secondaire des minerais en milieu alcalin concentré, soit à l'origine de la baisse de réactivité observée lors de leur électrolyse. Parallèlement une analyse thermodynamique avancée a été menée afin de déterminer les meilleures conditions théoriques de pression, de température et de concentration en NaOH pour effectuer l'électrolyse de l'hématite. La solubilité des composés de la gangue a été représentée avec des équations de Pitzer, et de nouveaux paramètres ont été calculés pour les interactions Na-SiO3-Al(OH)4. Cette étude thermodynamique a permis la conception et le pré-dimensionnement d'une étape de traitement des minerais par lixiviation alcaline
Modélisation et développement de diagnostics optiques pour la caractérisation de gouttes surfondues en écoulement ou en interaction avec un substrat sous-refroidi by Mehdi Stiti( )

1 edition published in 2020 in French and held by 1 WorldCat member library worldwide

Les phénomènes de givrage qui se produisent sur les aéronefs en vol peuvent constituer un danger majeur dans l'aéronautique. Les principaux problèmes de sécurité qui en résultent sont une visibilité réduite, un blocage des tubes de Pitot et une réduction des performances aérodynamiques. Dans ce contexte, les aéronefs doivent être certifiés pour différentes conditions de givrage susceptibles d'être rencontrées, notamment en lien avec la présence de gouttes surfondues de diamètres supérieurs à 50 µm dans l'atmosphère. Les étapes de certification sont réalisées à l'aide d'essais normatifs en soufflerie givrantes permettant de recréer des conditions aéronautiques givrantes proche de celles rencontrées en vol. Les objectifs des travaux présentés dans ce manuscrit portent sur la mise en œuvre d'une nouvelle technique optique basée sur la Fluorescence Induite par Laser (LIF) pour la caractérisation de gouttes surfondues : température, détection de leurs états (i.e. liquide, solide ou mixte), caractérisation des gouttes en phase mixte et dynamique du front de solidification dans une goutte impactant un substrat sous-refroidi. Une première technique de LIF, mettant en jeux deux traceurs fluorescents et trois bandes spectrales de détection, permet de mesurer ponctuellement la température de gouttes surfondues en écoulement ainsi qu'estimer la fraction de glace contenue dans une population de gouttes en écoulement. Des mesures réalisées dans des conditions voisines de celles rencontrées en aéronautiques ont été réalisées dans une soufflerie givrante de la DGA Essais-Propulseurs et ont montré la difficulté de reproduire des conditions aéronautiques givrantes réelles (gouttes à l'équilibre thermique avec la phase porteuse). Une seconde technique basée sur l'Imagerie rapide de fluorescence induite par laser (PLIF) a été développée pour l'étude de la solidification d'une goutte impactant un substrat sous-refroidi. Cette nouvelle méthode de PLIF permet d'accéder, pour la première fois, à la dynamique et la morphologie du front de solidification à l'intérieur de la goutte. L'étude a porté sur des impacts de gouttes sur un substrat sec et sur un substrat recouvert d'une couche de glace. Le deuxième cas permet de s'affranchir du phénomène de surfusion de l'eau et donc du caractère aléatoire du déclenchement de la solidification. Les mesures ont montré que l'évolution du front de solidification et les caractéristiques de la pointe formée par la goutte en fin de solidification étaient dépendantes de la nature du substrat (conductivité thermique) et de l'angle de contact goutte/substrat
Synthesis of enantiopure 3,4-dihydro-2H-1,4-benzoxazine analogues for potential biological applications by Hong-Ngoc Pham( )

1 edition published in 2020 in English and held by 1 WorldCat member library worldwide

This work describes the syntheis and conformational analysis of enantiopure 1,4-benzoxazine-based pseudodipeptides and pseudotripeptides. Enantiomers of ethyl 2,3-dibromopropionate and ethyl 3,4-dihydro-2H-1,4-benzoxazine-2-carboxylate are obtained by two strategies (i) via enantioselective synthesis and (ii) via preparative HPLC enantioseparation of racemate on multigram scale. Because of the racemization process during the enantioselective synthesis, preparative HPLC enantioseparation on racemates are successfully applied to afford enantiomers with high enantiomeric purities (ee ≥ 99.5%). Both enantiomers of the 1,4-benzoxazine compound are used to design new 1,4-benzoxazine-based pseudopeptides via peptide coupling reactions on C- and N-terminal extremities. Their conformational behaviour in solution and solid states are investigated by spectroscopic (IR, NMR) and X-Ray diffraction analyses. The results indicate (i) a predominant C5 pseudocycle involving a lone pair of electrons of oxygen in 1,4-benzoxazine ring with NH group from C-extremity elongation and (ii) a slight influence of the absolute configuration at C2 position of 1,4-benzoxazine scaffold and the side chains of amino acids
Study of the separation by organic solvent nanofiltration of diluted solutes using commercial, dense and porous membranes and their derivatives by deposition of polyelectrolyte nanolayers by Mahbub Morshed( )

1 edition published in 2019 in English and held by 1 WorldCat member library worldwide

The objective of this study was to improve the OSN separation performance of commercial membranes for metathesis applications in which highly diluted catalysts are used. In this work, commercial polymeric membranes were first studied to characterize their performance in organic media using very dilute solute-solvent binary mixtures. Based on a literature review, it was shown that the PERVAP4060 membrane, of which PDMS is the dense active layer, was a promising candidate for organic solvent nanofiltration (OSN). As a porous membrane, the AMS and PAN commercial supports have also been taken into account. In this study, we considered the modification on the surface to improve the separation properties of polymeric OSN membranes. Ar/O2 plasma and/or polyelectrolytes multilayers were used for the preparation of new prototype membranes. Unmodified and modified membranes were tested under OSN conditions using binary feed mixtures. Several highly dilute solutes, organophosphorus ligand R-BINAP, phase transfer catalyst ToABR, and linear alkanes have been studied. Both R-BINAP and ToABR were used in the range of 0.0001 to 0.5% by weight, and most experiments were subsequently performed with 0.05% solute concentrations in toluene. It has been shown that PDMS can retain 80% R-BINAP and about 93% ToABr in toluene. After modification by the LBL deposition, the rejection is improved with the modified PERVAP4060 membranes, leading to an 88% rejection of R-BINAP with a deposit of 10 PAH / PSS polyelectrolyte bilayers at the surface and this rejection being able to reach 95% when the number of bilayers is 20. ToABr rejection increases to 97% with the ten bilayered membranes. The performance of the membrane was studied under different pressures of between 1 and 40 bar; the high rejection, still observed in these OSN conditions, strongly supports a solution-diffusion transfer mechanism through the PDMS. The treatment of ternary mixtures mimicking the catalyst/solute/ solvent mixture corresponding to the hydroformylation has also been studied; no evidence of coupling was detected, and the highest retention remained unchanged. On the other hand, the improvement of the rejection also observed from the porous membranes after modification. The rejection of C44 in the AMS was reached 75% after modification by tention10 bilayers of PDDA / PSS, whereas it was only 25% before modification. In the modified PAN, the rejection of the solutes obtained is in the range of 37 to 50%, whereas it was only 3 to 7% by weight before modification. The disadvantage of the porous membrane, however, is the sharp decrease in flux after the deposition of the multiple layers
Comportement au feu du matériau bois : auto-inflammation, dégradation et auto-extinction by Lucas Terrei( )

1 edition published in 2020 in French and held by 1 WorldCat member library worldwide

The construction of positive energy and low carbon footprint buildings is a real response to the environmental issues and challenges of the coming decades. An increasing number of high-rise building construction projects made largely of wood are either under study or under construction. A key issue for the construction of such buildings is the fire behavior of these structures. Indeed, when the wood is subjected to a high heat flux, it will degrade and it can self-ignite. Conversely, in certain conditions, wood can self-extinguish. However, the bibliography shows the disparity concerning experimental results for a same material subjected to a given test such as the cone calorimeter. The results on the wood extinction remain limited in view of recent research carried out on this phenomenon. The aim of the thesis is to experimentally study the self-ignition, degradation and self-extinction of the wood material used in buildings. For this, many tests at different scales have been performed to examine the ability of the wood material to self-ignite or self-extinct under prescribed conditions. A total of 600 tests, were performed in vertical orientation and allowed to consolidate results with a statistical approach. A dedicated experimental setup has been deployed on each experimental device studied: an infrared camera providing to measure the surface temperature of the samples when they are subjected to a heat flux, two fast cameras (visible and infrared) in order to record the location and the auto-ignition mechanisms and very thin thermocouples embedded in the wood to measure the temperature evolution in the material according to fixed conditions. Results showed that for the auto-ignition (i.e. without pilot), the notion of ignition temperature of the material could be questionable when the ignition occurs at short times. Indeed, the flame appearance is, in most of the experiments, at a distance far from the exposed surface to the heat flux. The ignition mechanisms do not depend on the surface temperature but on the gas / air mixing conditions as well as the mixture temperature. The auto-ignition surface temperature makes therefore sense only for long auto-ignition times, for which ignition occurs close to the surface. The samples degradation depends on many factors: sample orientation, sample humidity, wood species, oxygen concentration in the atmosphere. The effect of these parameters was considered in this work. A particular attention was focused on the establishment of a metrology aimed at obtaining precise and accurate measurements. Very thin thermocouples, embedded in the sample and oriented parallel to the isotherms allow a better estimation of the temperature and were therefore used. Finally, a new experimental device based on two cones calorimeter arranged on a sliding table system was set up and made it possible to determine simple criteria for wood self-extinguishment at small scale
Étude de faisabilité de la valorisation en bioraffinerie de biomasses issues de phytotechnologies : cas d'une plante hyperaccumulatrice (noccaea caerulescens) et d'un ligneux (salix viminalis) by Zahra Menana( )

1 edition published in 2018 in French and held by 1 WorldCat member library worldwide

La phytoremédiation est un concept pour la dépollution et de réhabilitation des sols et/ou de friches industrielles contaminés par des éléments traces métalliques (ETMs), utilisant les végétaux pour absorber ou immobiliser les contaminants en présence des organismes microbiens de la rhizosphère. Cette technique a pour conséquence une production de biomasse plus ou moins contaminée qu'il est nécessaire de traiter et également de valoriser. Cependant, la présence d'ETMs peut être problématique dans une approche de conversion en bioraffinerie. Pour répondre à cette question, deux espèces ont été étudiées : une plante herbacée hyperaccumulatrice (Noccaea caerulescens) et un ligneux (Salix viminalis). Deux prétraitements ont été sélectionnés pour cette étude : les prétraitements par explosion vapeur et organosolv, en appliquant différentes conditions opératoires, afin (1) de suivre la distribution des ETMs au cours du traitement, (2) de purifier la matière lignocellulosique et (3) d'évaluer l'effet des ETMs sur les étapes ultérieures d'hydrolyse enzymatique et de fermentation. Pour le prétraitement organosolv la majeure partie des ETMs est récupérée dans le résidu solide cellulosique alors que par explosion à la vapeur, les ETMs sont extraits en grande partie dans les effluents aqueux du traitement. La présence d'ETMs dans les pâtes cellulosiques et les hydrolysats ne montre pas d'effet significatif sur la cinétique d'hydrolyse enzymatique et de fermentation. Concernant spécifiquement Noccaea caerulescens des teneurs relativement importantes en pectines ont été observées, ce qui ouvre des perspectives intéressantes pour la valorisation de cette plante par la production d'un biopolymère d'intérêt industriel. Finalement, les résultats obtenus montrent qu'il serait possible de combiner réhabilitation des sols et valorisation en bioraffinerie de biomasses issues de phytotechnologies soit pour la production du bioéthanol ou la production de molécules plateforme
Caractérisation des usinages robotisés : Application aux processus de transformation du matériau bois by Oussama Ayari( )

1 edition published in 2020 in French and held by 1 WorldCat member library worldwide

Nowadays, the robotization of wood machining remains a complicated and uncommon task. This is also due to the significant constraints to which the use of an industrial robot (also known as anthropomorphic or polyarticulated) is subject. These particularly concern operations that require a high degree of precision and agility. Indeed, the forces exerted on the robot's articulations and on the tooling come up against the insufficient natural rigidity of polyarticulated robots. This causes the machine to lose its performance in terms of output and efficiency and degrades the quality of machining. In addition, the variable properties of the wood material do not make the polyarticulated robot the ideal candidate for material removal machining processes. In order to answer this problem, we seek, through this thesis, to improve the machining of robotized wood by taking into account the major technological difficulties: natural rigidity, dimensional quality of machining and cutting forces and interaction between them. Thus the difficulties related to the wood anatomy: Heterogeneity, anisotropy, fibrous texture and singularities. To solve this problem we used a numerically controlled (CNC) machine tool and an anthropomorphic ®Kuka robot equipped with a high-speed machining engine. We instrumented our experimental bench with a force measuring chain and a digital measuring table to quantify the dimensional errors of the machined profiles. Three wood materials are machined: Hardwood (Beech), softwood (Fir) and derived timber (MDF). The results obtained show that there is a direct proportional relationship between cutting forces and degradation of dimensional quality, regardless of the machine used. The higher the forces applied to remove the material, the more the tracking performance of the end effector decreases. In terms of system stability, measurements have shown that the farther the tool works from the robot base, the more the cutting forces fluctuate and the more the dimensional quality deteriorates. This becomes more pronounced when material heterogeneity and density are high. As a result, the robot is less stable and its performance in terms of repeatability in series production degrades. Fluctuations in stress and degradation of dimensional quality are intensified by changing the cutting mode. Cutting forces increase by a factor of 8 when the tool works perpendicular to the wood grain.The case of material-related peculiarities is discussed. Indeed, measurements show a rapid and sudden jump in forces which multiplies by 3 when the cutting edge passes through a knot. This leads to splinters and cracks in the material and degrades the orthogonality of the cut. The variation of the robot feed rates from 4m/min to 9m/min in beech machining resulted in damage to the machined surface in the form of material ripples and splinters due to deviations in the tool path. The same experiments on the variation of the robot feed rates are carried out on other species such as larch (softwood) and oak (hardwood) to study the machining quality. The results found are similar to those obtained previously (material splinters, tool path deviations and cracks)
Dimensionnement et étude expérimentale d'un vaporiseur à milli-canaux by Guillaume Henry( )

1 edition published in 2020 in French and held by 1 WorldCat member library worldwide

The ever-growing awareness of the impact of human activities on the environment makes industries find environmentally friendly alternatives. In the automotive sector, the development of less polluting cars using hydrogen as fuel is an example. To successfully promote this type of vehicles to people, the providing network of hydrogen has to be set up. To tackle the challenge of this deployment, Air Liquide, through the FAIR project (Additive manufacturing for the intensification of reactors), aims to intensify the Steam Methane Reforming process in order to develop small mobile hydrogen production unit. Inside this process, a particular step, the water vaporisation, has to be intensified. To study this intensification, an experimental test bench and a vaporisation module are sized, assembled and instrumented in the Reactions and Chemical Engineering Laboratory (LRGP) in Nancy. The test bench uses a hot oil convection to vaporise the water. The vaporisation module, designed as a milli-structured plate heat-exchanger, has a window enabling the visualisation and the recording of the boiling water hydrodynamics with a high-speed camera. Four milli-structured plates are tested: two of them have 10 semi-circular straight channels either mechanically engraved of made by additive manufacturing, the third plate has various shapes of engraved channels and finally the fourth plate has 7 engraved straight channels with triangular cavities. An innovative method for the post-treatment of high-speed videos is developed in order to produce Spatio-Temporal Diagrams (DST) showing the spatial evolution of liquid-vapor interfaces by the time inside a channel. The exploitation of this new tool enables the determination and the description of boiling phenomena (spontaneous bubble nucleation, liquid oscillations), the understanding of the boiling events chronology and the characterisation of flow regimes (bubbly, slug, churn, annular flow and dry out of the channel). Moreover, a quantitative exploitation of the DST is possible such as the local vapor quality needed for the drawing of flow regime map. Thanks to the measurement of various operating data on the test bench, the characterisation of the heat losses is done in order to assess the vapor quality of the water flow outgoing the vaporiser by a heat balance. The two-phase heat-transfer coefficients are also assessed. Finally, a methodology of milli-structured vaporiser made by additive manufacturing pre-sizing is put forward. It is based on two case-study on the intensification of water vaporisation in a small mobile hydrogen production unit and in a standard SMR process
Estimation d'énergies de GIBBS de solvatation pour les modèles cinétiques d'auto-oxydation : développement d'une banque de données étendue et recherche d'équations d'état cubiques et SAFT adaptées à leur prédiction by Edouard Moine( )

1 edition published in 2018 in French and held by 1 WorldCat member library worldwide

Liquid phase oxidation of hydrocarbons (also called autoxidation) is central to a large number of processes in the petrochemical industry as it plays a key role in the conversion of petroleum feedstock into valuable organic chemicals. This phenomenon is also crucial in oxidation-stability studies of fuels and its derivatives (aging). These liquid-phase oxidation reactions entail radical mechanisms involving more than thousands of compounds and elementary reactions. Kinetic modelling of these kinds of reactions remains a significant challenge because it requires thermodynamic and kinetic parameters, which are not abundant in literature. The EXGAS software, developed at LRGP, is able to generate these kinds of models but only for oxidation reactions taking place in a gaseous phase. It is assumed that the nature of elementary reactions in the liquid and gaseous phases is the same. The unique need to transfer a kinetic mechanism from a gas phase to a liquid phase is to update kinetic rate constant values and equilibrium constant values (called thermokinetic constants) of mechanism reactions. Therefore, in the framework of this PhD thesis, a new method aimed at applying a correction term to thermokinetic constants of gaseous phases is proposed in order to obtain constants usable to describe liquid-phase mechanisms. This correction involves a quantity called partial molar solvation GIBBS energy. An analysis of the precise definition of this property led us to conclude that it can be simply expressed as a function of fugacity coefficients and liquid molar density. As a result, this property could also be expressed with respect to measurable thermodynamic quantities as activity coefficients or HENRY's law constants. By combining all the experimental data related to these measurable properties that can be found in the literature, it was possible to develop a comprehensive databank of partial molar solvation GIBBS energies (called the CompSol database). This database was used to validate the use of the UMR-PRU equation of state to predict solvation quantities. Moreover, the bases of a new parameterization for SAFT-type equations of state were laid. It consists in estimating pure-component parameters of SAFT-like equation using a very simple, reproducible and transparent path for non-associating pure components. This equation was used to calculate partial molar GIBBS energy of solvation of pure and mixed solutes. Last, equations of state were combined with EXGAS software to model the oxidation of n-butane in the liquid phase
Filtration d'aérosols de suie en présence de vapeur et/ou de gouttelettes d'eau by Charlotte Godoy( )

1 edition published in 2019 in French and held by 1 WorldCat member library worldwide

One of the most frequently used methods to purify air contaminated by particles, in many industrial processes, is filter media. These collective equipment for protecting people and the environment are proven in terms of initial efficiency, but their behavior over time remains difficult to predict. This is all the more noticeable when these devices are confronted with a biphasic aerosol composed of solid and liquid particles. These situations can be encountered during metals machining, pesticides spreading or even during fires in confined areas such as nuclear power plants. The proposed study will aim to establish the performance of a fibrous media with respect to biphasic aerosols with nanostructured solid particles and droplets (submicron or micron-sized). If the filtration of solid aerosols or liquid aerosols is relatively well documented in the literature, no study has been interested in this problem of biphasic aerosols. For high solid / liquid ratios, the time course of the pressure drop should be close to solid aerosols filtration evolution, ie a quasi-linear increase over time. In the case of an aerosol predominantly made up of droplets, a constant pressure drop overtime, characterized by a state of equilibrium between the mass flow rate of collected droplets and the flow rate of liquid drained on the downstream face of the filter, could be considered . But what about the evolution of the pressure drop between these two extremes? The determination of the temporal evolution of the collection efficiency is also uncertain and should be regarded as a real metrological challenge
Kinetic study of ester biofuels in flames by Artëm Dmitriev( )

1 edition published in 2020 in English and held by 1 WorldCat member library worldwide

Le progrès partout dans le monde nécessite une variété de sources d'énergie propre. Les biocarburants liquides de type ester semblent être très efficaces dans ce contexte, car ils sont faciles à utiliser dans les véhicules modernes, ils peuvent être produits à partir de diverses ressources renouvelables et ils offrent des caractéristiques de combustion respectueuses de l'environnement. À cet égard, les esters éthyliques d'acides gras (EEAG) sont considérés comme une classe prometteuse de biocarburants. L'objectif principal de cette thèse était de développer un mécanisme cinétique chimique actualisé de la combustion des EEAG légers jusqu'au pentanoate d'éthyle et de le valider par rapport aux nouvelles données expérimentales sur la structure de flammes laminaires prémélangées à basse pression et pression atmosphérique. Les flammes alimentées par trois EEAG, l'acétate d'éthyle, le butanoate d'éthyle et le pentanoate d'éthyle, ont été étudiées au moyen de la spectrométrie de masse avec faisceau moléculaire et de la chromatographie en phase gazeuse. Plus de 40 espèces stables et intermédiaires comprenant des radicaux ont été détectées et quantifiées dans les flammes. Une analyse complète du mécanisme développé a été réalisée. La thèse se compose de 3 chapitres. Le premier chapitre présente une revue bibliographique. Les études expérimentales et théoriques les plus importantes sur la combustion des EEAG sont discutées. Le deuxième chapitre présente un aperçu des méthodes expérimentales et de simulation utilisées dans la thèse. Des détails sur le développement du mécanisme sont également fournis dans cette partie. Le dernier chapitre présente des résultats expérimentaux et de modélisation sur les esters étudiés en comparaison avec les mécanismes cinétiques de la littérature
Optimal Helical Tube Design for Intensified Heat / Mass Exchangers by Omran Abushammala( )

1 edition published in 2020 in English and held by 1 WorldCat member library worldwide

The search for technological solutions aimed at minimizing the size of a device, known as intensification, is a classic objective of process engineering. In this thesis, the intensification possibilities offered by helical tubes are studied, both for heat and mass exchangers. The use of helical tubes instead of straight tubes is indeed of interest both in terms of increasing the exchange surface per unit volume between the two fluids circulating in the exchanger and by the possibility of increasing the transfers by generating Dean vortices in the tubes. A set of CFD (Computational Fluid Dynamics) type simulations was carried out and compared with experimental results. In the end, on the basis of a systematic approach using correlations, a volume reduction of a factor of 8 was obtained, both for heat exchangers and for membrane contactors
Étude critique de quelques techniques expérimentales d'évaluation de la coulabilité des poudres by Assia Saker( )

1 edition published in 2018 in French and held by 1 WorldCat member library worldwide

In industrial sectors, such as chemical, pharmaceutical or food industries, poor flowability of powders is often the causes of process malfunction. Poor flowability can lead to the blocking of powders in a silo, dosing and filling problems, or even bad quality on final product. To ensure proper process operation, it is therefore necessary and essential to evaluate the flowability of powders used. For this purpose, several experimental techniques such as angle of repose devices, shear cells or powder packing devices can be used. Flowability indices can then be defined in order to classify the powders according to the flow quality. Experimental tests have been carried out on several types of powders and the first results have shown that the transition from one technique to another can modify or even reverse the classification of the powder flowability. Indeed, according to the techniques studied, powders are subjected to different mechanical stresses and therefore the choice of the technique must be adapted to the real case of study. In this work, we were particularly interested to the evaluation of powders flowability from compaction devices. The work carried out has shown that the dynamic parameters (amplitude and frequency of taps) greatly influence the classification of powders flowability. From an energy approach, it has been shown that the evaluation of the flowability from Hausner ratio can be given by a compaction technique only if it achieves a value of energy required to obtain a maximal compaction of the particles. Finally, an implementation study of flowability evaluation techniques was carried out in the field of formulation by focusing on the quantitative evaluation of the influence of a glidant
Characterization of gas-liquid hydrodynamics and mass transfer in SMX static mixers by Marco Scala( )

1 edition published in 2019 in English and held by 1 WorldCat member library worldwide

The mixing of two or more fluids is a rather common operation in all industrial processes. The main target of the mixing is to increase the interface area between phases in order to improve mass and heat transfer and facilitate then chemical reaction. Among the multiphase mixing stands out the gas liquid dispersion. The aim of the present work is to examine a specific type of mixers, namely the static mixer. Static mixers are located into a housing or pipeline to ensure a high blending of fluids. They are usually made by a series of inserts, in turn designed by holes, helical elements and oblique blades. These elements cause local accelerations and stretching of the fluid currents to reach a high mixing efficiency. The wide applications of static mixers in numerous industrial processes require better knowledge of the hydrodynamics in these devices. The gas-liquid flow pattern through a Sulzer static mixer SMXTM mounted in a vertical cylindrical tube was investigated in this study. The main goal was to assess the performance of the Sulzer static mixer SMXTM for gas-liquid applications in industrial processes. Experimental data were collected from two main optical techniques, Backlight Shadowgraph Technique (BST) and Particle Image Velocimetry (PIV). 3D-printed static mixers were manufactured using transparent plastic in order to provide optical access. Three different liquids were used as the continuous phase, namely water, water with SDS and normal-heptane. The liquid phase was kept stagnant during the experiments. Five different lengths of mixers (with 1, 2, 5, 10 and 15 elements respectively) and several gaseous nitrogen flow rates from 1 to 10 l/h were analysed. The behaviour of the simple tube without mixing device, acting like a bubble column, was investigated as a reference, for comparison purposes with the SMXTM. Bubble diameter distributions at the inlet and outlet of the SMX mixers were evaluated. The velocity fields inside the mixers were quantified. The gas hold-up was also measured. The oxygen transfer performance in the SMX static mixer in air/water mixture was assessed by measuring the overall oxygen transferred. The mass transfer coefficient to the interfacial area kLa was determined and proved to be larger in the mixer. Volume-of-fluid numerical simulations of the mixer were performed with OpenFOAM. These 3D simulations were mainly focused on the behaviour of the SMX in an organic system at low gas flow rate (1 l/h). The numerical simulations were satisfactorily validated by experimental results. The comparison and the combination of the numerical and experimental results bring new insight into the flow pattern in a SMXTM static mixer
Valorisation de résidus miniers riches en fer : Conception et développement d'un procédé de production de fer électrolytique à partir de matrices complexes by Abdoulaye Maihatchi Ahamed( )

1 edition published in 2020 in French and held by 1 WorldCat member library worldwide

The increase in world population (from 2.5 billion in 1950 to 10 billion in 2050 according to the United Nations) is leading to an increase in the need for metals. These metals come from mines, but their production from ores generates huge quantities of tailings. These tailings occupy large storage areas and very often contain metals that can be extracted. The recovery of these metals would not only make it possible to reduce their volume and ecological footprint, but also and above all to produce metals with high added value to meet the needs of new technologies. Two types of iron-rich residues were studied in this work in order to extract iron and zinc by electroplating: red mud and jarosite. In the first case, these are residues from the production of alumina from bauxite ore by the Bayer process (alkaline process). The second type of residues, jarosite, comes from the production of zinc by the "jarosite" process. Two experimental approaches have been set up for this purpose. Direct electrodeposition in the case of red mud: the samples are directly suspended in a 12.5 mol/L NaOH solution and the iron (in the form of hematite and/or goethite) is electrodeposited on a graphite cathode at a temperature of 110°C. In the case of jarosite, a different approach has been used: (i) a leaching of the jarosite in a sulphuric acid medium, (ii) a blende leaching to reduce the ferric iron to ferrous iron and to enrich the bath in zinc, (iii) a cementation of the copper by a zinc powder and finally (iv) an iron-zinc alloy electrodeposition step. In both cases of residues, several operating parameters were tested in order to optimize leaching yield, electrodeposition, deposit quality and faradaic yield. For the red mud, the best faradaic yield (72%) were obtained for a solid/liquid ratio of 1/3 (g/mL), a NaOH concentration of 12.5 mol/L, a current density of 41 A/m² and a temperature of 110°C. The electrolytic iron deposits, analyzed by ICP-AES, DRX, SEM/EDX, have a purity of more than 97% iron by mass. For jarosite, the best leaching yield (for zinc and iron were 73% and 70% respectively) were obtained for a sulphuric acid concentration of 1.5 M, a solid/liquid ratio of 1/10 (g/mL) and a temperature of 80°C for 7 hours. Electrodeposition tests produced zinc-iron alloys with different iron contents. The faradaic yield obtained under optimal conditions (current density of 800 A/m² and a temperature of 20°C) was of the order of 89%. The results obtained in this study confirm the technical feasibility of iron and iron-zinc alloy electroplating from complex matrices. This opens up a new alternative to the valorisation of mining residues by the metal electrodeposition technique
L'étude de l'influence de la structure chimique des additifs sur le contrôle de la réactivité des carburants by Minh Duy Le( )

1 edition published in 2020 in English and held by 1 WorldCat member library worldwide

Modern societies require cleaner and more efficient internal combustion engines. This constraint has involved a significant evolution in the combustion systems and fuel formulation. Engine-fuel adequacy is the key item to be optimized to achieve this goal. Among adjustable parameters, the reactivity of the fuel is the most important characteristic to be considered. This leads to an increasing use of additives that allows fuel to meet various combustion requirements. However, the design and the use of additives still faces a lack of comprehension regarding their effect. In this context, this thesis aims to better understand the chemical effect of additives on the fuel gas-phase reactivity. Three additives including a cetane booster, an octane booster, and a free radical scavenger are considered: 2-ethylhexyl nitrate, ferrocene, and 2,4-xylenol, respectively. The chemical effect of these additives on the reactivity of a surrogate fuel containing 35% n-heptane and 65% toluene by volume was experimentally and numerically investigated. Experiments were conducted in three devices: a shock tube, a rapid compression machine, and a heat flux burner. The use of these experimental devices allows to explore the reactivity over a wide range of engine-relevant conditions. For simulations, a detailed kinetic model was developed based on recent literature data. The satisfactory agreement between experiments and simulations enables to propose several hypothesis regarding the chemical effect of the additives
Traitement des eaux usées dans des bioréacteurs multitrophiques grâce à des flocs de microalguesbactéries valorisables en biogaz by Olfa Beji( )

1 edition published in 2018 in French and held by 1 WorldCat member library worldwide

The biological treatment of urban and industrial wastewaters represents a process with a negative impact on the environment and on climate change through the emission of greenhouse gases (GHG), particularly CO2. In the presence of light, microalgae-bacteria flocs (MaB-flocs) have been integrated into photobioreactors with fixed biomass to ensure a sustainable wastewater treatment without O2 supply and CO2 release. The entrapment of flocs in PVA-alginate beads has shown the effect of physicochemical and hydrodynamic conditions on the elimination of pollutants and the multicellularity evolution within multi-scale bioreactors. In addition, the immobilization of biomass on biodegradable olive carriers and on PVC disks provided a better performance of fluidized bed and rotating discs bioreactors, respectively, for the bioremediation of wastewater. The properties of the supports (porosity, roughness, and structure) and the hydrodynamic behaviors have favored the attachment of multitrophic biofilms. Biofilm development shows the effect of multitrophic interactions between microalgae and bacteria on the organic compounds (COD) and nutrients (ammonium and phosphorus) removals. The MaB-flocs biomass was recovered and reused for the treatment of the digestate and to improve the production of biomethane by anaerobic co-digestion. This integrated multitrophic technology makes it possible to obtain zero wastes at the end of the process
 
moreShow More Titles
fewerShow Fewer Titles
Audience Level
0
Audience Level
1
  Kids General Special  
Audience level: 0.96 (from 0.96 for Filtration ... to 0.96 for Filtration ...)

Alternative Names
École doctorale 608

École doctorale Sciences et ingénierie des molécules, des produits, des procédés, et de l'énergie

École doctorale SIMPPé

ED 608

ED608

SIMPPé

Languages
French (12)

English (8)