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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
211

The Development of a Knowledge-Based Wax Deposition, Three Yield Stresses Model and Failure Mechanisms for Re-starting Petroleum Field Pipelines. Building on Chang and Boger’s Yield Stresses Model, Bidmus and Mehrotra’s Wax Deposition and Lee et al.’s Adhesive-Cohesive Failure Concepts to better Underpin Restart Operation of Waxy Crude Oil Pipelines

Fakroun, Abubaker A. January 2017 (has links)
Twenty years ago, Chang et al. (1998) introduced the three-yield stresses concept (dynamic, static and elastic limits) to describe yielding of waxy crude oils cooled below the wax appearance temperature (WAT). At the time, the limits in rheological instruments were such that they never actually measured the elastic-limit, a key fundamental property. Using modern instruments, this research succeeds in recording for the first time the entire yielding process down to stresses of 10-7 Pa and shear rate of 10-6 min-1 as a function of temperature, cooling rate and stress loading rate using two waxy oils of different origins and wax content. A four-yield stress model is established using derivative data (dynamic fluidity and failure acceleration). In addition, calorimetry (DSC) and microscopy (CPM) helped extract WAT, the gel and pour points and link gel crystal structure and its yielding and breakage to rheological properties. The yielding stresses measured rheologically were tested in laboratory pipelines at two diameter scales, 6.5mm and 13.5mm to compare stresses in uniform and non-uniform cooling. It is demonstrated that rheological instruments can only predict gel breaking pressure when the cooling rate is low, i.e. yielding at the pipe wall. A complementary heat transfer study was performed on a section of pipe statically cooled, both experimentally and theoretically to predict the gel front-liquid oil interface that develops in industrial pipeline where gel breaking occurs. This key information together with rheological data provide the means to predict accurately restart pressures of shut gelled pipelines that have eluded previous research. / Ministry of Higher Education of the Libyan Government
212

Aprovechamiento y mejora de crudos extrapesados

Corresa Mateu, Elena 20 October 2023 (has links)
[ES] Durante la presente tesis doctoral se ha desarrollado un proceso de mejora parcial in-situ en superficie de un crudo extrapesado que ha permitido obtener un buen rendimiento a un crudo sintético que cumple con las especificaciones necesarias para ser transportado a través de un oleoducto, esto es, un crudo sintético con una gravedad API superior a 19, una viscosidad inferior a los 300 cSt y libre de asfaltenos. Además, se ha conseguido eliminar prácticamente el 99% en peso de los metales, níquel y vanadio, presentes en el crudo de partida, lo que facilita el posterior procesado de este crudo sintético en una refinería. Las reacciones necesarias para desarrollar este proceso se han llevado a cabo utilizado una unidad Micro-Downer (MDU). Dicha unidad consta de un reactor de lecho transportado descendente y permite obtener resultados a nivel de laboratorio similares a los que se obtendrían al procesar cualquier crudo en un reactor tipo FCC a escala industrial. Se han estudiado las condiciones de reacción (temperatura, tiempo de residencia y relación sólido a carga) más adecuadas para llevar a cabo el craqueo térmico de un crudo extrapesado en este tipo de reactores. Asimismo, se ha encontrado que entre varios materiales sólidos con diferentes propiedades ácidas y texturales, es con el caolín, una arcilla natural con un cierto grado de porosidad residual en su estructura cristalina, con el que se obtiene el mayor rendimiento a productos líquidos que cumplen los requisitos de densidad y viscosidad necesarios para poder ser transportados a través de un oleoducto. Estos resultados se han obtenido tras llevar a cabo la reacción en condiciones no severas (530ºC, 0,3 s de tiempo de residencia y una relación sólido a carga de 8 g g¿1), y que por tanto no requieren de un elevado gasto energético. En contrapartida, se ha detectado que con cada uno de los sólidos utilizados y en cualquiera de las condiciones de operación estudiadas, todos los crudos sintéticos recogidos son inestables con respecto a la floculación de los asfaltenos. Con el fin de subsanar esta limitación de la tesis doctoral, en el apartado siguiente se ha intentado eliminar la fracción de asfaltenos de los líquidos finales. Para ello se ha utilizado, ya sea como sustituto del caolín o como aditivo junto a él, un material sólido con actividad para el craqueo de fondo (BCA, del inglés Bottom Cracking Additive). De este modo se pretende eliminar esta fracción de asfaltenos mediante craqueo catalítico, dando lugar a la formación de otras fracciones más ligeras de crudo, y/o mediante reacciones de condensación dan- do lugar a la formación de coque. En este apartado ha quedado demostrado que la presencia de un cierto grado de acidez, aunque residual, en el sólido de intercambio de calor empleado para procesar un crudo extrapesado como el utilizado para realizar este estudio, conlleva un incremento en el rendimiento a coque cuya principal consecuencia es una importante bajada en el rendimiento a crudo sintético final sin que, en contrapartida, se consiga eliminar el problema de la presencia de asfaltenos en los líquidos finales. Tras comprobar que para obtener crudos sintéticos estables con respecto a la fioculación de los asfaltenos es necesario eliminar la fracción residuo, es decir, los hidrocarburos con puntos de ebullición superior a los 537ºC, el siguiente paso se ha centrado en encontrar una combinación de etapas con las que sea posible convertir, o reciclar hasta la extinción, esta fracción residuo. Con este fin se han ideado tres estrategias de procesos de mejora y se han llevado a cabo estimaciones teóricas que nos han permitido conocer la mejor estrategia de procesado para obtener el mayor rendimiento a crudo sintético estable. Finalmente, la validez de este nuevo procesos se ha estimado comparando estos resultados experimentales obtenidos a escala de laboratorio con los generados al procesar este mismo crudo extrapesado en una planta piloto de delayed coking. / [CA] Durant la present tesi doctoral s'ha desenvolupat un procés de millora parcial in-*situ en superfície d'un cru extrapesado que ha permès obtenir un bon rendiment a un cru sintètic que compleix amb les especificacions necessàries per a ser transportat a través d'un oleoducte, això és, un cru sintètic amb una gravetat API superior a 19, una viscositat inferior als 300 cSt i lliure de asfaltenos. A més, s'ha aconseguit eliminar pràcticament el 99% en pes dels metalls, níquel i vanadi, presents en el cru de partida, la qual cosa facilita el posterior processament d'aquest cru sintètic en una refineria. Les reaccions necessàries per a desenvolupar aquest procés s'han dut a terme utilitzat una unitat Micro-Downer (MDU). Aquesta unitat consta d'un reactor de llit transportat descendent i permet obtenir resultats a nivell de laboratori similars als que s'obtindrien en processar qualsevol cru en un reactor tipus FCC a escala industrial. S'han estudiat les condicions de reacció (temperatura, temps de residència i relació sòlid a càrrega) més adequades per a dur a terme el craqueig tèrmic d'un cru extrapesado en aquest tipus de reactors. Així mateix, s'ha trobat que entre diversos materials sòlids amb diferents propietats àcides i texturales, és amb el caolí, una argila natural amb un cert grau de porositat residual en la seua estructura cristal·lina, amb el qual s'obté el major rendiment a productes líquids que compleixen els requisits de densitat i viscositat necessaris per a poder ser transportats a través d'un oleoducte. Aquests resultats s'han obtingut després de dur a terme la reacció en condicions no severes (530 °C, 0,3 s de temps de residència i una relació sòlid a càrrega de 8 g g1), i que per tant no requereixen d'una elevada despesa energètica. En contrapartida, s'ha detectat que amb cadascun dels sòlids utilitzats i en qualsevol de les condicions d'operació estudiades, tots els crus sintètics arreplegats són inestables respecte a la floculació dels asfaltenos. Amb la finalitat d'esmenar aquesta limitació de la tesi doctoral, en l'apartat següent s'ha intentat eliminar la fracció de asfaltenos dels líquids finals. Per a això s'ha utilitzat, ja siga com a substitut del caolí o com a additiu al costat d'ell, un material sòlid amb activitat per al craqueig de fons (BCA, de l'anglès Bottom Cracking Additive). D'aquesta manera es pretén eliminar aquesta fracció de asfaltenos mitjançant craqueig catalític, donant lloc a la formació d'altres fraccions més lleugeres de cru, i/o mitjançant reaccions de condensació donen- do lloc a la formació de coc. En aquest apartat ha quedat demostrat que la presència d'un cert grau d'acidesa, encara que residual, en el sòlid d'intercanvi de calor emprada per a processar un cru extrapesado com l'utilitzat per a realitzar aquest estudi, comporta un increment en el rendiment a coc la principal conseqüència del qual és una important baixada en el rendiment a cru sintètic final sense que, en contrapartida, s'aconseguisca eliminar el problema de la presència de asfaltenos en els líquids finals. Després de comprovar que per a obtenir crus sintètics estables respecte a la fioculación dels asfaltenos és necessari eliminar la fracció residu, és a dir, els hidrocarburs amb punts d'ebullició superior als 537 °C, el següent pas s'ha centrat en trobar una combinació d'etapes amb les quals siga possible convertir, o reciclar fins a l'extinció, aquesta fracció residu. A aquest efecte s'han ideat tres estratègies de processos de millora i s'han dut a terme estimacions teòriques que ens han permès conèixer la millor estratègia de processament per a obtenir el major rendiment a cru sintètic estable. Finalment, la validesa d'aquest nou processos s'ha estimat comparant aquests resultats experimentals obtinguts a escala de laboratori amb els generats en processar aquest mateix cru extrapesado en una planta pilot de delayed coking. / [EN] During this doctoral thesis it has been developed an in-situ extra-heavy crude oil partial upgrading process that has allowed to obtain a good yield to a synthetic crude oil that meets the requirements of density and viscosity to be transported through a pipeline, that is, a synthetic crude with an API gravity grater than 19, a viscosity of less than 300 cSt and free of asphaltenes. Furthermore, practically all the metals, nickel and vanadium, have been removed from the starting extra-heavy crude oil, which greatly facilitates the further processing of this syncrude in a refinery. In order to develop this process a study has been conducted to determine the ideal reaction conditions (temperature, residence time and solid to oil ratio) to carry out the thermal cracking reaction of an extra-heavy crude oil in a downflow transported bed reactor. Moreover, it has been found that among several solid materials with different acidities and textural properties, it is the Kaolín, a natural clay with a small degree of porosity in its crystalline structure, which yields the largest amount of synthetic crude with the density and viscosity values required to be transported through an oil pipeline. These results have been obtained after performing the reaction under non-severe conditions (530ºC, 0.3 seconds and 8g g¿1) and therefore do not require a high energy expenditure. However, the liquids collected after each of the reactions carried out are unstable with respect to asphaltene flocculation, regardless of the solid heat exchanger or the reaction conditions used. To overcome this shortcoming, the next step has focused on eliminating asphaltenes from the synthetic crude. To do so, it has been employed, either alone or as an additive together with kaolin, a heat exchange solid with a certain grade of activity to performe the catalytic cracking of heavy molecules (BCA, Bottom Cracking Additive). This would allow asphaltenes removal by means of catalytic cracking reactions, giving rise to lighter hydrocarbons formation, and/or by means of condensation reactions, giving rise to coke formation. In this section it has been concluded that, due to the characteristics of the composition of the extraheavy crude oil used in the present study, the presence of any kind of acidity on the solid used as heat exchanger lead to a such increase in coke yield, with the concomitant reduction in the yield to syncrude, that made its used inadvisable. In addition, asphaltene flocculation continues to be observed within the reduced amount of liquids collected. So that, after assuming that in order to obtain stable liquids respect asphaltenes flocculation it is mandatory to get a syncrude free of residue fraction, hydrocarbon products with boiling points higher than 537ºC, in the next section has been analyzed the combination of different process steps to either thermally convert or recycle to extinction this heavy hydrocarbons fraction. Three different strategies of improvement processes have been schematized and the best one to produce the greatest amount of stable synthetic crude has been determined through theoretical calculations. Finally, this new partial upgrading process has been assessed by comparing these results obtained experimentally in the laboratory with the ones obtained after processing the same extraheavy crude oil in a Delayed Coking pilot plant. / Corresa Mateu, E. (2023). Aprovechamiento y mejora de crudos extrapesados [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/198857
213

[en] STUDY ABOUT MARITIME OIL EXPORTS: METROLOGICAL ASPECT / [pt] ESTUDO SOBRE A EXPORTAÇÃO MARÍTIMA DE PETRÓLEO: ASPECTO METROLÓGICO

ROBERTO DA COSTA CARDOSO 07 January 2015 (has links)
[pt] Por muito tempo, os sistemas de medição dinâmica de petróleo não foram usados para a transferência de custódia. Eles eram utilizados basicamente para fins operacionais, como detectar vazamentos e transferências internas. O aumento progressivo dos preços do barril de petróleo exigiu das medições de petróleo uma incerteza cada vez menor, o que provocou o desenvolvimento de novas tecnologias que resultaram em sistemas dinâmicos de medição de alta precisão a serem utilizados na transferência de custódia. Nesta pesquisa foi avaliada a substituição das medições estáticas por medições dinâmicas no faturamento de exportações marítimas de petróleo, com o objetivo de agilizar as operações de carregamento de navios em píeres diminuindo a indisponibilidade dos recursos logísticos envolvidos, de minimizar a exposição da companhia a perdas financeiras devido a faturamentos errôneos e de verificar que essa diminuição da exposição justifica o investimento em sistemas de medição dinâmica. Foram descritas as medições de tanques de terra, as medições de tanques de navio e os sistemas de medição dinâmica, avaliando procedimentos, equipamentos, além de restrições, problemas e incertezas associadas a cada método. Foi dada atenção especial aos procedimentos de arqueação de tanques para armazenamento de granéis líquidos, comparando procedimentos utilizados no Brasil pelo Inmetro aos requisitos da Norma ISO -7507, e a rastreabilidade metrológica dos equipamentos de medição em relação aos procedimentos utilizados na sua calibração. / [en] For many years, dynamic measurement systems have not been used in the petroleum industry for custody transfer applications, only for operational reasons like detecting leaks and internal transfers. The progressive growth of crude oil prices required measurements with a smaller uncertainty, leading to developing news technologies, resulting in high accuracy flow meters to be used in custody transfer. The main objective of this research was evaluate the replacement of static measurements by dynamic measurements in oil exports sales in order to speed up the loading of vessels, decreasing the unavailability of logistical resources involved, to minimize the company s exposure to economic losses due to erroneous bill of ladings and verify if this justifies the investment in dynamic measurement systems. This research has discussed a number of issues associated with the uncertainty of the shore tanks, vessels tanks and dynamic measurements, evaluating procedures, equipment, and restrictions, problems and accuracy associated with each method. It also included a discussion about the difference between calibration of vertical cylindrical tanks procedures used in Brazil by Inmetro and the requirements of ISO -7507, and about traceability of measuring equipment calibration.
214

Desenvolvimento de métodos eletroanalíticos (análise por redissolução e eletroforese capilar) para a determinação de metais e ânions em combustíveis e derivados de petróleo / Development of electroanalytical methods (Stripping Analysis and Capillary Electrophoresis) for the determination of metals and anions in fuels and petroleum-based products

Muñoz, Rodrigo Alejandro Abarza 15 March 2006 (has links)
Neste trabalho foram desenvolvidos métodos eletroanalíticos (redissolução potenciométrica e voltamétrica) para a determinação de metais (mercúrio, cobre, chumbo e zinco) em petróleo, óleo diesel, óleo lubrificante e álcool combustível. Para analisar álcool, foi também desenvolvido um método por eletroforese capilar, que possibilita a determinação de cátions (sódio, potássio e cálcio) e ânions (cloreto, sulfato e nitrato). Procedimentos envolvendo a utilização de fornos de microondas (focalizadas - que opera a pressão atmosférica - e com cavidade, que promove a digestão em frascos pressurizados) para a decomposição de petróleo, óleo diesel e óleo lubrificante são descritos. As determinações de cobre e mercúrio por redissolução potenciométrica apresentaram melhores limites de detecção do que a voltametria de redissolução de onda quadrada nas amostras digeridas, utilizando eletrodos de ouro confeccionados a partir de CDs graváveis (Cdtrodos), como eletrodo de trabalho. Para a determinação de chumbo e zinco nas mesmas amostras digeridas, os melhores resultados foram obtidos com eletrodos de filme de mercúrio e utilizando a voltametria de redissolução potenciométrica. Perdas de mercúrio por volatilização foram verificadas quando as amostras foram digeridas em fornos de microondas focalizadas. Para os demais metais, a utilização deste forno foi vantajosa por proporcionar melhores limites de detecção devido à utilização de maiores massas de amostra no processo de digestão. A utilização de um banho ultrassônico de bancada para promover a extração de cobre e chumbo de óleos lubrificantes na presença da mistura 1:1 (v/v) de HClconc. e H2O2 (30% m/v) mostrou-se eficiente. Trinta minutos de exposição à energia ultrassônica foram necessários para a extração quantitativa de ambos os metais. Nas soluções extratoras, o teor dos metais foi determinado por voltametria de redissolução anódica, usando CDtrodos. Os limites de detecção do método para a determinação de cobre e chumbo foram, respectivamente, de 23 e 67 ng g-1 de óleo, aplicando 120 s de tempo de deposição. A voltametria de redissolução anódica em eletrodo de ouro possibilitou a determinação de cobre e chumbo em álcool combustível, sem qualquer tratamento prévio das amostras. Limites de detecção de 120 e 235 ng L-1 para cobre e chumbo, respectivamente, foram obtidos aplicando 15 min de tempo de deposição. Alternativamente, a evaporação do etanol seguido da redissolução em água desionizada permitiu a determinação dos metais por análise de redissolução. Todos os resultados obtidos utilizando diferentes metodologias de decomposição de amostras foram comparados com os resultados obtidos por análises por espectrometria de absorção atômica com forno de grafite. O método envolvendo a evaporação prévia, seguida da redissolução dos íons em meio aquoso também se mostrou muito favorável para realizar a determinação de cátions e ânions por eletroforese capilar em amostras de etanol hidratado combustível. Os íons Na+, K+ e Ca2+, Cl-, NO3- e SO42- foram encontrados nas amostras analisadas. Os limites de detecção destes íons se encontram na faixa de 0,06 e 0,18 mg L-1. / In this work eletroanalytical methodologies (potentiometric stripping analysis and anodic stripping voltammetry) for the determination of metals (mercury, copper, lead, and zinc) in crude oil, lubricating oil, diesel fuel, and ethanol fuel are proposed. A capillary electrophoresis method for ethanol fuel was developed to determine cations (sodium, potassium, and calcium) and anions (chloride, sulphate, and nitrate). Microwave digestion methods using different ovens (a focused microwave oven – operating at atmospheric pressure, and a cavity microwave oven, which employs pressurized vessels) for crude oil, lubricating oil, and diesel fuel are described. The determination of copper and mercury by potentiometric stripping analysis presents better detection limits than stripping voltammetric determinations for the digested sample analysis. Loss of mercury by volatilization was verified when samples were digested in the focused microwave oven. Otherwise, this oven presented some advantages for the other metals, as the improved detection limits due to the employment of higher sample mass for the digestion process. The use of a ultrasonic bath to promote the extraction of copper and lead from lubricating oils in the presence of 1:1 (v/v) HClconc and H2O2 (30% m/v) was efficient. Thirty minutes of ultrasonic exposure were necessary for quantitative exctraction of copper and lead. Anodic stripping voltammetry using gold CDtrodes was applied for metal determination in the extracted solutions. The detection limits of the proposed method for copper and lead were 23 and 67 ng g-1, respectively, under application of 120 seconds as deposition time. Anodic stripping voltammetry at a gold electrode was used for the determination of copper and lead in ethanol fuel, without any prior sample treatment. Detection limits of 120 and 235 ng L-1 for copper and lead, respectively, were attained applying 900 s as deposition time. Alternatively, the ethanol evaporation followed by re-suspension in deionised water allowed the metals determination by stripping analysis. All results obtained for sample decomposition methods were compared with the ones obtained by electrothermal atomic absorption spectrometric determinations. The method, which employs prior ethanol evaporation followed by re-suspension in deionised water, was applied for the determination of cations and anions by capillary electrophoresis in the hydrated ethanol fuel (automotive fuel). Na+, K+, Ca2+, Cl-, NO3-, and SO42- ions were found in the analyzed samples. The detection limits for these ions were situated between 0.06 and 0.18 mg L-1.
215

Capacité opérative des réseaux de transfert de pétrole / Operative capacity of crude oil local transportation networks

Rojas d'Onofrio, Jorge 17 March 2011 (has links)
Cette thèse étudie des systèmes locaux de gestion de transfert de pétrole ayant une architecture de réseau de canalisation. Pour leur représentativité, deux systèmes localisés au Venezuela et appartenant à l'entreprise PDVSA (Pétroles du Venezuela) ont été retenus pour illustrer les méthodes proposées et les valider : le Terminal Maritime de Pétrole de Guaraguao et le Centre de Stockage de Punta de Palmas. Dans ces réseaux des connexions, appelées « alignements », sont établies en ouvrant/fermant des vannes à travers d'un système SCADA (Supervisory Control and Data Acquisition). Le choix d'un alignement doit tenir compte de critères d'optimisation. La minimisation des interférences avec d'autres alignements, liée à la notion de capacité opérative, a été identifiée comme le critère de choix le plus important. Les contributions de cette thèse reposent sur une modélisation sous forme de graphes, et sur des algorithmes appartenant au domaine de la recherche opérationnelle. Elles contribuent à fournir aux opérateurs de supervision des outils d'analyse permettant d'optimiser le choix des alignements. Des indicateurs permettant de quantifier l'impact des opérations d'alignement ou des défaillances, sur la capacité opérative du système, sont proposés. La minimisation de l'impact sur la capacité opérative, va correspondre à la minimisation des interférences avec des alignements potentiels. Un algorithme de calcul de ces indicateurs, est présenté, ainsi que des algorithmes de recherche de chemin, de détermination d'éléments critiques, et de recherche d'alignements utilisant des pompes. Ces algorithmes sont basés sur des algorithmes classiques s'adressant au problème du plus court chemin, du flot maximum et du nombre maximum de chemins disjoints. Cependant, ils utilisent des méthodes innovantes, comme l'ajout de contraintes considérant l'existence de sous-types d'alignements, le calcul dynamique des coûts des chemins à partir de son impact sur la capacité opérative, et la recherche de chemins via un point intermédiaire obligatoire. Les contributions sont potentiellement applicables dans des domaines autres que le transport de pétrole. Les algorithmes ont été mis en œuvre en utilisant le langage Python et ont été testés en utilisant les données réelles des réseaux étudiés. L'objectif à moyen terme de ces travaux est le développement d'un logiciel d'assistance à la prise de décision. / This thesis studies local crude oil transportation systems with a pipe network architecture. Two representative systems, belonging to PDVSA (Venezuelan oil company), have been studied: the Guaraguao Crude Oil Seaport and the Punta de Palmas Tanks Yard. In this systems, connections, called "alignments", are established by opening/closing valves using a SCADA(Supervisory Control and Data Acquisition) system. Alignment choice is made based on optimization criteria. Interferences minimization with other alignments, related to the notion of operative capacity, has been identified as the most important criterion. The contributions of this thesis are based on graph modelling and algorithms from operational research. The main goal is to provide analysis tools allowing alignment choice optimization. Indexes permitting the quantification of alignments or failures impact on the operative capacity of the system are proposed. Minimizing the impact on the operative capacity will correspond to minimizing interferences with potential alignments. An algorithm computing these indexes is presented, as well as complementary developments such as a path search algorithm, an algorithm for critical elements determination, and algorithm for alignments using pumps. These algorithms are based on classical algorithms for the shortest path problem, the maximum flow problem and the maximum disjoint paths problem. However, they use innovative methods such as adding constraints when considering alignment sub-types, the dynamic computation of path costs based on their impact on operative capacity, and path search considering an obligatory intermediate node. These contributions can potentially be applied in areas other than oil transportation. The algorithms had been implemented in Python and had been tested using real data from the studied systems. The middle term goal of these works is the development of assistance software for decision making.
216

Processus géodynamiques, systèmes pétroliers, problématiques environnementales, ou de la versatilité des isotopes du plomb comme outils de traçage / Lead isotopes, versatile tracers of geodynamic processes, petroleum systems, and environmental issues

Fetter, Nadège 30 September 2019 (has links)
Le Pb est omniprésent dans les échantillons terrestres et sa relation avec ses ascendants radioactifs, l’U et le Th, en fait un marqueur de choix des processus géodynamiques.L’équipe lyonnaise de Janne Blichert-Toft et Francis Albarède a démontré, à travers une vaste compilation de données bibliographiques accompagnée de la production de nouvelles mesures, une correspondance entre la répartition des valeurs de composition isotopique du Pb dans la croûte continentale et la localisation de figures tectoniques majeures sur plusieurs continents (Bouchet et al., 2014 ; Blichert-Toft et al., 2016 ; Delile et al., 2014). L’existence de ces "provinces géochimiques" démontre l’intérêt des isotopes du Pb comme outil pour mieux comprendre comment l’histoire tectonique d’une région façonne la géochimie de ses continents. Un premier volet de ces travaux de thèse visait à compléter la base de données existante des compositions isotopiques du Pb dans la croûte continentale européenne, grâce à l’analyse de 104 échantillons de feldspaths potassiques issus de granites principalement originaires de Catalogne, de Corse, de Galice et de Kabylie, jusqu’ici restées en blanc sur les cartes précédemment établies. Les cartes ainsi obtenues, illustrant la répartition à travers l’Europe et le bassin méditerranéen des valeurs des "paramètres géochimiques" définis par Albarède et al. (2012), exprimant à partir des rapports isotopiques du Pb mesurés l’âge modèle de la roche et les fractionnements entre l’U, le Th et le Pb enregistrés en son sein, confirment le potentiel des isotopes du Pb comme traceurs robustes de l’héritage tectonique d’une région.Mais le cœur de cette thèse a été d’appliquer cet outil reliant chimie et histoire géodynamique que sont les isotopes du Pb à un type d’échantillon géologique pour lequel des analyses de haute précision de la compositions isotopique en Pb n’avaient jamais été entreprises jusqu’à maintenant : les pétroles bruts. Pour cela, il a fallu développer une méthode analytique novatrice permettant d’extraire le Pb de quelques millilitres de pétrole brut vers une solution aqueuse adaptée aux protocoles habituels de purification indispensables à des analyses isotopiques du Pb à haute précision par MC-ICP-MS (Fetter et al., 2019). Cette méthode a ensuite été appliquée à un total de 211 échantillons de pétrole brut issus de partout dans le monde. Des échantillons de roches mères d’hydrocarbures (schistes noirs) ont également été analysés afin de compléter les premières interprétations des résultats. Ce jeu de données unique met en évidence que le Pb contenu dans les pétroles bruts résultait du mélange d’au moins trois composantes d’âges modèles distincts : le pôle le plus radiogénique a été identifié comme associé aux roches mères des pétroles, tandis que les deux autres, d’âges modèles paléozoïque et protérozoïque, suggèrent des interactions conséquentes entre le pétrole et les roches encaissantes et sous-jacentes. Un nouveau modèle de migration du pétrole depuis sa roche mère a donc été proposé (Fetter et al., soumis), prenant en compte la forte implication des eaux circulant en profondeur dans les bassins sédimentaires en faisant intervenir un phénomène grandement négligé jusqu’à maintenant : la solubilité mutuelle de l’eau et du pétrole à haute température.La mise en évidence d’une dynamique complexe du Pb dans les pétroles bruts invalide une utilisation de ces derniers comme alternative aux feldspaths potassiques pour obtenir des données isotopiques en Pb fiables sur la croûte continentale européenne située sous les bassins sédimentaires. Cependant, elle ouvre de nouvelles portes quant à l’utilisation jusqu’ici inexplorée des isotopes du Pb comme traceurs de phénomènes de pollution associés à une prospection pétrolière peu responsable. / Lead is ubiquitous in terrestrial samples and its relationship to its radioactive ascendants, U and Th, makes it a prime tracer of geodynamic processes.The team of Janne Blichert-Toft and Francis Albarède, based in Lyon (France), has demonstrated on several continents, through large compilations of literature data supplemented by new measurements, a correspondence between the distribution of Pb isotopic compositions in the continental crust and major tectonic features (Bouchet et al., 2014 ; Blichert-Toft et al., 2016 ; Delile et al., 2014). The existence of these "geochemical provinces" has firmly established the potential of Pb isotopes as a tool for understanding how the tectonic history of a given region shaped its geochemistry. A first aspect of this PhD aimed at complementing the existing database of Pb isotopic compositions of the European continental crust through the analysis of 104 K-feldspar samples separated from granites originating mainly from Catalonia, Corsica, Galicia, and Kabylie, up until this PhD blank areas on the compiled map. The resulting updated maps showing the distribution throughout Europe and the circum-Mediterranean area of the "geochemical parameters" defined by Albarède et al. (2012), which derive a model age and fractionations between U, Th, and Pb from measured Pb isotopic ratios, confirm the potential of Pb isotopes as powerful tracers of the tectonic heritage of a given region.The core of this PhD, however, was to apply this tool connecting chemistry and geodynamic history to a type of geological sample so far never analyzed for high-precision Pb isotopic compositions: crude oil. To achieve this goal, a novel analytical method was developed which allows the extraction of Pb from a few milliliters of crude oil into an aqueous solution suitable for the standard Pb purification protocol essential for high-precision Pb isotope analysis by MC-ICPMS (Fetter et al., 2019). This method was then applied to a total of 211 crude oil samples from around the world. Hydrocarbon source rocks (black shales) also were analyzed. This unique data set reveals that Pb in crude oil results from the mixing of at least three endmembers of distinct model ages: the more radiogenic endmember is identified as the oil source rocks, while the other two components, of Paleozoic and Proterozoic ages, suggest considerable interactions between crude oil and the surrounding and underlying rocks. A new model was hence proposed for oil migration (Fetter et al., submitted), taking into account the key role of deep-seated waters circulating through the sedimentary basin by calling on a long-neglected phenomenon: mutual solubility of water and oil at high temperatures.Bringing to light the complex dynamics of Pb in crude oil invalidates the use of crude oil as an alternative to K-feldspars to obtain the Pb isotopic signature of the continental crust underlying sedimentary basins. However, it opens up new promising avenues for the yet unexplored use of Pb isotopes as tracers of irresponsible oil prospection related pollution.
217

Trapped Ion Mobility Spectrometry coupled to Fourier Transform Ion Cyclotron Resonance Mass Spectrometry for the analysis of Complex Mixtures.

Benigni, Paolo 18 September 2017 (has links)
Analytical Characterization of complex mixtures, such as crude oil, environmental samples, and biological mixtures, is challenging because of the large diversity of molecular components. Mass spectrometry based techniques are among the most powerful tools for the separation of molecules based on their molecular composition, and the coupling of ion mobility spectrometry has enabled the separation and structural elucidation using the tridimensional structure of the molecule. The present work expands the ability of analytical chemists by furthering the development of IMS-MS instrumentation by coupling Trapped Ion Mobility Spectrometry to Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (TIMS-FT-ICR MS). The TIMS-FT-ICR MS platform combines the high-resolution separation of TIMS, which has mobility resolving powers up to 400, and ultra-high mass resolution of FT-ICR MS, with mass resolving power over 1,000,000. This instrumentation allows the assignment of exact chemical composition for compounds in a complex mixture, as well as measurement of the collision cross-section of the molecule. Herein, the principles of the TIMS separation and its coupling to FT-ICR MS are described, as well as how the platform can be applied to targeted analysis of molecules, and untargeted characterization of complex mixtures. Molecular standards were analyzed by TIMS-MS in order to develop a computational workflow that can be utilized to elucidate molecular structure, using the measured collision cross-section of the ion. This workflow enabled identification of structural, cis/trans isomers, and chelated molecules and provides the basis for unsupervised structural elucidation of a complex mixture, and in particular for the elucidation of hydrocarbons from fossil fuels. In summary, this work presents the coupling of TIMS-FT-ICR MS and provides examples of applications as a proof of concept of the potential of this platform for solving complex analytical challenges.
218

Supply chain management and logistical considerations in distributing crude oil from Nigeria to China

Shiwoku, Mervyn Olakunle January 2018 (has links)
The evolution of supply chain management has made significant and continuous contributions to logistical processes. This is highly relevant to crude oil logistics in Nigeria, because both indigenous and multinational oil companies who distribute crude oil from Nigerian ports are yet to adopt an integrated export logistics operation. Besides, the study explores the philosophy of supply chain management applying theoretic frameworks of supply chain process management, demand variability, and vertical integration to encourage integrated export logistics for the distribution of crude oil from Nigeria to China. In addition, the research objectives are: to identify the components of crude oil exports; to review the principles of integrated supply chain management; to analyse crude oil demand in China; to evaluate the efficiency of oil distribution, and to propose strategies that will raise the efficiency of crude oil exports to China from Nigeria. A conceptual model was developed to identify relevant issues that guide the synergy of China’s requirement for energy security and Nigeria’s crude oil supply capability. Also, both a Delphi survey and an archival research method’s were adopted to elucidate on the characteristics of the research population, the shipment frequencies between the two countries, and the sources of competing crude oil exports to China. Measures of central tendency from respondent feedback and non-parametric tests support the study’s findings. Furthermore, recommendations for strategic, operational, and tactical organisation of resources were identified to raise integrated crude oil export efficiency from Nigeria to China directed by the theoretic framework. Moreover, their implications for sustainable logistics practice in the short, medium, and long-term are considered. Finally, it was found that adopting vertical integration in a crude oil supply chain will ensure responsiveness to support export efficiency, and enhance the geographic characteristics of Nigeria for increased export shipments to China.
219

Projeto, constru??o e an?lise de um prototipo vibracional em escala de bancada aplic?vel ao tratamento de ?gua de produ??o de petr?leo bruto, mediante inovadora opera??o h?brida de adsor??o e auto-flota??o / Design construction and testing of a laboratory vibrating prototype for treatment of oil production water, emulsion or the like, through hybrid operation of adsorption and self-flotation

Lacerda Junior, Jonatas Araujo de 28 April 2014 (has links)
Made available in DSpace on 2014-12-17T14:09:19Z (GMT). No. of bitstreams: 1 JonatasALJ_TESE.pdf: 9049452 bytes, checksum: dd9b668c8bc7791108be8a6bbc44e152 (MD5) Previous issue date: 2014-04-28 / A self-flotator vibrational prototype electromechanical drive for treatment of oil and water emulsion or like emulsion is presented and evaluated. Oil production and refining to obtain derivatives is carried out under arrangements technically referred to as on-shore and off-shore, ie, on the continent and in the sea. In Brazil 80 % of the petroleum production is taken at sea and area of deployment and it cost scale are worrisome. It is associated, oily water production on a large scale, carrier 95% of the potential pollutant of activity whose final destination is the environment medium, terrestrial or maritime. Although diversified set of techniques and water treatment systems are in use or research, we propose an innovative system that operates in a sustainable way without chemical additives, for the good of the ecosystem. Labyrinth adsor-bent is used in metal spirals, and laboratory scale flow. Equipment and process patents are claimed. Treatments were performed at different flow rates and bands often monitored with control systems, some built, other bought for this purpose. Measurements of the levels of oil and grease (OGC) of efluents treaty remained within the range of legal framework under test conditions. Adsorbents were weighed before and after treatment for obtaining oil impregna-tion, the performance goal of vibratory action and treatment as a whole. Treatment technolo-gies in course are referenced, to compare performance, qualitatively and quantitatively. The vibration energy consumption is faced with and without conventional flotation and self-flotation. There are good prospects for the proposed, especially in reducing the residence time, by capillary action system. The impregnation dimensionless parameter was created and confronted with consecrated dimensionless parameters, on the vibrational version, such as Weber number and Froude number in quadratic form, referred to as vibrational criticality. Re-sults suggest limits to the vibration intensity / Um prot?tipo vibr?til autoflotador de acionamento eletromec?nico para tratamento de ?gua de produ??o de petr?leo e emuls?o cong?nere ? apresentado e avaliado. A produ??o de petr?leo para refinamento e obten??o de derivados ? realizada sob modalidades tecnicamente referidas como on-shore e off-shore, isto ?, no continente e no mar. No Brasil 80% da produ??o petrol?-fera ? feita no mar e ?rea de implanta??o e escala de custo s?o preocupantes. Associa-se ?gua oleosa de produ??o, efluente abundante em larga escala, carreadora de 95% do potencial polu-idor da atividade cujo destino final ? o meio ambiente mar?timo ou terrestre. Embora diversi-ficado conjunto de t?cnicas e sistemas de tratamento d ?gua encontram-se em uso ou pesqui-sa, prop?e-se um sistema inovador que opera de forma sustent?vel sem aditivos qu?micos, pa-ra o bem do ecossistema. Utilizou-se labirinto adsorvente, em espirais met?licos, e escala la-boratorial de fluxo. Patentes de equipamento e processo s?o reivindicadas. Realizaram-se tra-tamentos em vaz?es e faixas de frequ?ncia distintas, monitoradas com sistemas de controle, uns constru?dos, outros aquistados para tal. Medi??es do teor de ?leo e graxa (TOG) do eflu-ente tratado mantiveram-se dentro do intervalo de enquadramento legal nas condi??es de en-saio. Pesaram-se os adsorventes antes e ap?s o tratamento para obten??o da impregna??o de ?leo, meta de desempenho da a??o vibrat?ria e tratamento como um todo. Tecnologias atuais de tratamento s?o referenciadas para compara??o de desempenho, qualitativa e quantitativa-mente. Confrontou-se consumo energ?tico operando-se em vibra??o, com e sem flota??o con-vencional, e com autoflota??o. Vislumbram-se boas perspectivas de rendimento do sistema proposto, sobretudo, na redu??o do tempo de resid?ncia por a??o de capilaridade. Criou-se o par?metro adimensional de impregna??o e se lhe confrontou com consagrados par?metros a-dimensionais, na vers?o vibracional, como n?mero de Weber e n?mero de Froud quadr?tico, referido como criticalidade vibr?til. Resultados sugerem limites ? intensidade vibrat?ria
220

Estudo avançado para caracterização química de petróleo do Campo de Carmópolis-Sergipe

Santos, Jandyson Machado 22 February 2013 (has links)
This work presents the use of analytical techniques, conventional and advanced for the chemical characterization of four samples of blends crude oils from the PETROBRAS station, Oiteirinhos II (Carmópolis-SE). These samples, which have different exploration characteristics, were identified as CEOL 1, CEOL 2, CEOL 3 and CEOL 4. After the collection in the field and subsequently separation of water residue through centrifugation at 2500 rpm, the blends were characterized by density, asphaltenes content, fractionation SARA (saturates, aromatics, resins and asphaltenes) and by the application of micropyrolisys off-line. The advanced characterization to elucidate the chemical relationship between the samples were made using the Thermogravimetry (TGA), Infrared Spectroscopy (IR), Spectroscopy in Ultraviolet (UV), Matrix Assisted Laser Desorption Ionization - Time of Flight - Mass Spectrometry (MALDI-TOF-MS), Gas Chromatography Mass Spectrometry (GC/MS), Gas Chromatography with Flame Ionization Detector (GC-FID) and Comprehensive Two-Dimensional Gas Chromatography (GC x GC). The blends CEOL 3 presented the highest density (0.9737 g mL-1), confirming the results of MALDI-TOF-MS, that shows predominantly high molecular mass compounds in the composition. The SARA fractionation indicates the Saturated fraction as the largest fraction in all oils (> 50%). The analysis of TGA explained similar bands of mass loss in all blends and their asphaltenes. The characterization by IR showed bands related to the hydrocarbon composition and the UV showed the presence of mono, di and tri aromatics structures in the blends as well in their respective asphaltenes. The chromatographic analysis (GC/MS, GC-FID and GC x GC) showed that all blends have a paraffinic profile, with the predominance of n-alkanes of low molecular weight (n-C10 to n-C40) and characteristics of oxide depositional environment (Pr/Ph>1) and lacustrine origin (CPI>1). The analysis by GC/MS showed that the distribution area relating to the free n-alkanes in the CEOL 3 blends is approximately 30% lower than the other samples, and that after the micropyrolysis process these areas become approximately the same. For biomarkers, GC/MS was possible to identify the majority presence of tri- and tetracyclic terpanes (m/z 191) and regular steranes (m/z 217) as the major constituents of the blends, pointing also to the release of occluded biomarkers in asphaltenic structures after the micropyrolysis process. The identification and subsequent correlation between biomarkers indicated that the blends crude oils studied have partial biodegradation characteristics, with a blend of mature and immature oils from terrigenous and/or algal organic matter. / Este trabalho apresenta o emprego de diversas técnicas analíticas, convencionais e avançadas, para a caracterização química de quatro blendas de óleos brutos provenientes da estação da Petrobras de Oiteirinhos II (Carmópolis-SE). Estas amostras, que apresentam diferentes características de exploração, foram identificadas como CEOL 1, CEOL 2, CEOL 3 e CEOL 4. Após a coleta em campo e posterior separação dos resíduos de água por centrifugação a 2500 rpm, as blendas foram caracterizados a partir da determinação da densidade, do teor de asfaltenos, fracionamento SARA (Saturados, Aromáticos, Resinas e Asfaltenos) e aplicação da micropirólise off-line. A caracterização avançada, aplicada para elucidar a relação química entre as amostras, foram realizadas utilizando as técnicas de Termogravimetria (TGA), Espectroscopia no Infravermelho (IV), Espectroscopia no Ultravioleta (UV), Espectrometria de Massa por Tempo de voo com Desorção-Ionização a Laser Assistida por Matriz (MALDI-TOF-MS), Cromatografia Gasosa acoplada a Espectrometria de Massas (CG/EM), Cromatografia Gasosa com Detector de Ionização de Chama (CG-DIC) e Cromatografia Gasosa Bidimensional Abrangente (CG x CG). A blenda CEOL 3 apresentou a maior densidade (0,9737 g mL-1) corroborando com os resultados de MALDI-TOF-MS, mostrando a predominância de compostos de alta massa molecular em sua composição. O fracionamento SARA aponta a fração de Saturados como a maior fração em todos as blendas (>50%). A análise de TGA expôs faixas de perdas de massas semelhantes em todas as amostras e seus asfaltenos. A caracterização por IV apresentou estiramentos referentes à composição de hidrocarbonetos e o UV a presença de estruturas mono, di e tri aromáticos tanto nas blendas como em seus respectivos asfaltenos. As análises cromatográficas (CG/EM, CG-DIC e CG x CG) mostraram que todos as blendas possuem um perfil parafínico, com predominância de n-alcanos de baixo peso molecular (n-C10 a n-C40) com características de ambiente deposicional óxido (Pr/Ft>1) de origem lacustre (CPI>1). A análise por CG/EM mostrou ainda que a distribuição em área referente a n-alcanos livres presentes na blenda CEOL 3 é cerca de 30% menor do que as outras amostras, e que após o processo de micropirólise essas áreas passam a ser aproximadamente iguais. Para biomarcadores, por CG/EM foi possível identificar a presença majoritária de terpanos tri e tetracíclicos (m/z 191) e esteranos regulares (m/z 217), como constituintes majoritários das blendas em estudo, apontando ainda, a liberação de biomarcadores ocluídos nas estruturas asfaltênicas após o processo de micropirólise. A identificação e posterior correlação entre os biomarcadores indicaram que as blendas de óleos brutos possuem características de biodegradação parcial, com uma mistura de muito e pouco evoluídos termicamente, provenientes de matéria orgânicas terrígenas e/ou algas.

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