This thesis presents the investigations conducted in the use of ultrasonic technology to measure two-phase flow in both horizontal and vertical pipe flows which is important for the petroleum industry. However, there are still key challenges to measure parameters of the multiphase flow accurately. Four methods of ultrasonic technologies were explored. The Hilbert-Huang transform (HHT) was first applied to the ultrasound signals of air-water flow on horizontal flow for measurement of the parameters of the two- phase slug flow. The use of the HHT technique is sensitive enough to detect the hydrodynamics of the slug flow. The results of the experiments are compared with correlations in the literature and are in good agreement. Next, experimental data of air-water two-phase flow under slug, elongated bubble, stratified-wavy and stratified flow regimes were used to develop an objective flow regime classification of two-phase flow using the ultrasonic Doppler sensor and artificial neural network (ANN). The classifications using the power spectral density (PSD) and discrete wavelet transform (DWT) features have accuracies of 87% and 95.6% respectively. This is considerably more promising as it uses non-invasive and non-radioactive sensors. Moreover, ultrasonic pulse wave transducers with centre frequencies of 1MHz and 7.5MHz were used to measure two-phase flow both in horizontal and vertical flow pipes. The liquid level measurement was compared with the conductivity probes technique and agreed qualitatively. However, in the vertical with a gas volume fraction (GVF) higher than 20%, the ultrasound signals were attenuated. Furthermore, gas-liquid and oil-water two-phase flow rates in a vertical upward flow were measured using a combination of an ultrasound Doppler sensor and gamma densitometer. The results showed that the flow gas and liquid flow rates measured are within ±10% for low void fraction tests, water-cut measurements are within ±10%, densities within ±5%, and void fractions within ±10%. These findings are good results for a relatively fast flowing multiphase flow.

Oil terminals are complex infrastructures due to their diverse operational activities. They are exposed to diverse risks because they usually operate in a dynamic environment in which safety barriers are sometime overwhelmed, leading to the disruption of operations due to a high level of uncertainty. However, the ability of oil terminals to minimise vulnerability and maximise resilience depends on the availability of the correct anticipated information at the right time for a decision-making process. An important finding from the reviewed literature revealed that uncertainties and the unpredictability of the convergent effect of several hazardous factors have the potential to cause major disruptions such as fire, explosion and transit accidents. The consequences of these disruptions can lead to infrastructure damage and loss of life. The common operational threats to oil terminal operations (OTOs) substantiates the need for a holistic resilience model for operations in offshore/onshore terminals such as berthing/unberthing, vessel manoeuvring, loading and offloading, storage, etc. Due to the uncertainties associated with these operations and the cases of reported incidents/accidents, this research focuses more on the aspect of loading and offloading operations at ship/terminal interface. An emphasis on a resilience modelling approach provides a flexible yet robust model for OTOs to address disruption proactively, particularly with constantly evolving hazards and threats. This thesis introduces an innovative approach towards resilience modelling based on a developed novel framework. The key aspect of the framework was supported using three proposed models: (1) the integration of Utility Theory and Swiss Cheese Model (UtiSch_+), to evaluate the relative importance of the identified hazard factors (HFs), (2) a Bayesian network (BN), to calculate the overall probability that a specific hazard is present and, (3) an Analytical Hierarchical Process (AHP) - Prospect Theory (PT) approach, as an important model for a strategic decision selection method. An empirical study was conducted to test the validity the proposed models, using case studies and Sensitivity Analysis (SA). The result obtained demonstrated that the models are effective techniques to obtain the relative weight of the identified Hazard Factors (HFs) in order to prioritise them, for dynamic hazards probability evaluation and to prioritise suggested resilience strategies in order of importance to mitigate hazard/risk level. Evidently, the result revealed appears reasonable and appropriate for investment, in order to support a strategic decision for the selection of a resilience strategy for resilience improvement in OTOs.

The identification of petroleum acids, also known as ‘naphthenic’ acids (NA), has been an analytical challenge for over 140 years. However, most recent interest in NA has arisen due to concerns over their presence and apparent associated toxic effect in oil platform produced waters and oil sands process waters (OSPW), respectively. Understanding the toxicity, transformations during biodegradation and remediation treatments and predicting the fate of NA in the environment will be aided by the identification of individual NA. However the elucidation of individual acid structures by standard chromatographic techniques, such as GC-MS, has so far been limited by the extreme complexity of the NA mixtures. Recent analysis of NA as the methyl ester derivatives, by multidimensional gas chromatography-mass spectrometry (GC×GC-MS), has resulted in the identification of several tri- to pentacyclic, aromatic and sulphur-containing acids as well as tricyclic diacids. Therefore the current investigation focused on the identification of the abundant bicyclic acids in petroleum and OSPW acid extracts, utilising the unparalleled chromatographic separation and mass spectrometric detection offered by GC×GC-MS. Analysis of fractionated NA as methyl esters, resulted in the first identification of several bicyclic acids in OSPW including several novel bridged bicyclic acids, several fused bicyclic acids, as well as some terpenoid-derived drimane and labdane acids. However, identifications were limited somewhat by a lack of reference mass spectra and lack of availability of reference compounds for co-chromatography. A complementary method, based on an historical approach, involving reduction of NA esters to hydrocarbons, was modified and substantially improved. Analysis of the hydrocarbons resulting from the reduced acids, by GC×GC-MS, and comparison of the hydrocarbon mass spectra with the more abundant reference spectra available for petroleum hydrocarbons, resulted in the identification of over 40 individual bicyclic acids including fused, bridged and terpenoid-derived acids. The study provides the most comprehensive analysis of one of the major classes of NA (the bicyclic acids) to date. The methods developed were applied to the structural elucidation of NA in commercial NA and OSPW NA and resulted in the identification of numerous alicyclic, aromatic and sulphur-containing acids, supporting and extending previous identifications. There is clear potential for this method to be used for the identification of other unknown acids and functionalised biomarkers in complex matrices. The new knowledge of the acid structures in petroleum and OSPW NA can now be used to inform future research into the environmental monitoring and toxicity of NA.

Face à l'épuisement des pétroles bruts légers et à la demande en énergies fossiles toujours croissante, l'exploitation des pétroles lourds et le raffinage des résidus pétroliers devient une nécessité. Cependant, la nature de ces résidus pose de nombreuses difficultés aux procédés de raffinage existants. En conséquence, l'industrie pétrolière a actuellement un fort intérêt au développement d'un procédé de conversion profonde de ces résidus pétroliers en carburants valorisables. L'utilisation d'un catalyseur hautement dispersé dans la charge permettrait de minimiser ces difficultés. L'objectif de cette thèse est alors l'étude de quelques aspects du développement d'un procédé d'hydroconversion des résidus pétroliers avec des catalyseurs dispersés. La première partie est dédiée à la génération des données expérimentales de la conversion d'un résidu dans un micro-pilote continu en faisant varier les conditions opératoires. Ensuite, un modèle de cette unité a été développé en couplant la description des cinétiques chimiques déterminée dans un autre réacteur (dans une étude préalable), avec les modèles physiques (hydrodynamique et transfert de matière) et thermodynamiques. Le modèle a été validé en comparant les prédictions du modèle avec les résultats expérimentaux obtenus. La minimisation de la consommation de catalyseur et l'augmentation du rendement en produits désirables sont deux objectifs dans le développement d'un procédé industriel. Le recyclage du catalyseur et de la fraction non-convertie est une stratégie permettant d'atteindre ces objectifs. L'outil expérimental utilisé pour l'étude du fonctionnement en mode recyclage était un réacteur semi-continu. La caractérisation des produits issus d'expériences de la conversion avec un catalyseur recyclé est accompagnée d'une caractérisation de la phase active. De plus, l'étude de l'évolution de la réactivité de la charge recyclée fait partie de cette étude. Les résultats obtenus permettent d'évaluer la faisabilité du fonctionnement en recyclage / With the depletion of light petroleum crude oils and the demand in fossil energies still growing, the exploration of heavy oils and the refining of petroleum residues becomes a necessity. However, the nature of these feedstocks presents numerous difficulties for the existing refining processes. As a consequence, the petroleum industry is currently developing new processes for the deep conversion of these residues to more valuable fuels. The utilization of dispersed catalysts is a promising new strategy for minimizing these difficulties. The aim of this work was to study several aspects of the scale-up of a hydroconversion process of petroleum residues with dispersed catalysts. The first part of this work is dedicated to the generation of experimental data for the conversion of a residue in a continuous micro-pilot unit by varying the operating conditions. Afterwards, a model of the unit was developed by coupling the chemical kinetics determined in a previous batch reactor study with the physical characterization (hydrodynamics and mass transfer) of the continuous micro-pilot unit. The model was validated by comparing its predictions with the experimental data. Minimization of catalyst consummation and the increasing product yields are vital in the development of an industrial process. Recycling the non-converted fraction as well as the catalyst is is a strategy to achieve these two objectives. The second part was thus dedicated to the study of the recycling mode, which was carried out in a semi-continuous reactor. The product characterization of catalyst recycling experiments was accompanied with the characterization of the active phase to evaluate the performance of an aging catalyst. Additionally, the evolution of the reactivity of the recycled product was studied. The results obtained allow us to evaluate the feasibility of the recycling mode

The oil and gas industry need for high performing and low cost multiphase meters is ever more justified given the rapid depletion of conventional oil reserves. This has led oil companies to develop smaller/marginal fields and reservoirs in remote locations and deep offshore, thereby placing great demands for compact and more cost effective soluti8ons of on-line continuous multiphase flow measurement. The pattern recognition approach for clamp-on multiphase measurement employed in this research study provides one means for meeting this need. Cont/d.

Waterflooding is a common type of oil recovery techniques where water is pumped into the reservoir for increased productivity. Reservoir states change with time, as such, different injection and production settings will be required to lead the process to optimal operation which is actually a dynamic optimization problem. This could be solved through optimal control techniques which traditionally can only provide an open-loop solution. However, this solution is not appropriate for reservoir production due to numerous uncertain properties involved. Models that are updated through the current industrial practice of ‘history matching’ may fail to predict reality correctly and therefore, solutions based on history-matched models may be suboptimal or non-optimal at all. Due to its ability in counteracting the effects uncertainties, direct feedback control has been proposed recently for optimal waterflooding operations. In this work, two feedback approaches were developed for waterflooding process optimization. The first approach is based on the principle of receding horizon control (RHC) while the second is a new dynamic optimization method developed from the technique of self-optimizing control (SOC). For the SOC methodology, appropriate controlled variables (CVs) as combinations of measurement histories and manipulated variables are first derived through regression based on simulation data obtained from a nominal model. Then the optimal feedback control law was represented as a linear function of measurement histories from the CVs obtained. Based on simulation studies, the RHC approach was found to be very sensitive to uncertainties when the nominal model differed significantly from the conceived real reservoir. The SOC methodology on the other hand, was shown to achieve an operational profit with only 2% worse than the true optimal control, but 30% better than the open-loop optimal control under the same uncertainties. The simplicity of the developed SOC approach coupled with its robustness to handle uncertainties proved its potentials to real industrial applications.

Gas-liquid annular two phase flow in pipes is important in the oil and gas, nuclear and the process industries. It has been identified as one of the most frequently encountered flow regimes and many models (empirical and theoretical) for the film flow and droplet behaviour for example have been developed since the 1950s. However, the behaviour in large pipes (those with diameter greater than 100 mm) has not been fully explored. As a result, the two- phase flow characteristics, data, and models specifically for such pipes are scarce or non-existent such that those from smaller pipes are extrapolated for use in design and operation. Many authors have cautioned against this approach since multiphase pipe flow behaviour is different between small and large pipes. For instance the typical slug flows seem not to occur in vertical upwards flows when the pipe diameter exceeds 100 mm. It is therefore imperative that theoretical models and empirical correlations for such large diameter pipes are specifically developed.

People's narratives, interpretations and understandings of the Chad-Cameroon Oil Pipeline and pipeline actors emphasise the uneven exercise of power through which structural violence is effected and experienced. The complexity of the processes of structural violence along with local socio-political context and peoples' dynamic understandings thereof play major roles in shaping resistance practices, in complex ways in Kribi and Nanga-Eboko. Working from these narratives, I offer a theoretical re-articulation of structural violence as (i) tangible through the body, (ii) historically compounded, (iii) spatially compressed and (iv) enacted in a globalised geopolitical nexus by actors who are spatially nested within a racialised and gendered hierarchy of scale. Drawing from critical interdisciplinary work on violence, my theory of a triad of divergent, often interrelated and co-existing, distinguishable indexes of structural violence includes: infra/structural violence, industrial structural violence and institutionalized structural violence. The particular processes and mechanisms of uneven power within structural violence, local socio-political contexts and the epistemologies through which power is conceived (in this case I consider epistemologies of la sorcellerie, or witchcraft) inform resistance practices; I illuminate key operations (within geographies characterised by high levels of infra/structural violence) within the spatial practices of power that influence the tendency for resistance struggles to be quiet, spontaneous and/or labour-based. I conclude with a discussion of the political and intellectual value of academic work on life and being amid structural violence, emphasising the need to move beyond the invisible/visible dichotomy that has often informed intellectual work on structural violence.

L'objectif de cette étude consiste à développer une approche permettant d'économiser de l'énergie de haut niveau thermique dans le procédé de la distillation atmosphérique du pétrole. Cette approche repose sur le fait que l'installation de plusieurs flashs sur le train de préchauffage de ce procédé associée à un choix approprié du plateau d'alimentation des vapeurs résultantes à la colonne de distillation, provoque une diminution de la chaleur apportée à ce train de préchauffage. Le déficit de chaleur de haut niveau thermique ainsi créé est causé par la réduction des débits des reflux latéraux de la colonne de distillation et il est compensé par de la chaleur de bas niveau thermique apportée par les effluents résiduaires disponibles dans toute la raffinerie. Cette approche peut être appliquée aux nouveaux procédés comme à l'expansion des procédés existants et l'économie d'énergie de haut niveau thermique dans le four peut atteindre les 21%. Une réduction équivalente des gaz à effet de serre est aussi observée / The objective of this thesis is to demonstrate, on thermodynamic grounds, that introducing a flash in the preheating train of an atmospheric oil distillation process , together with an appropriate feeding of the resulting vapors into the column, could potentially bring substantial energy savings by reducing the duty of the preheating furnace and by reducing the distillation column irreversibilities. This idea has been expended by showing how this can be done while keeping the throughput and the product characteristics unchanged. The outcome is that placing several flashes after the heat exchangers and feeding the corresponding vapor streams to the appropriate trays of the column, reduces the pumparound flows and then the heat brought to the preheating train. The resulting heat deficit may then be compensated in additional heat exchangers by using low level heat recuperated from the products of the distillation and/or imported from other processes. The use of this residual heat reduces the furnace duty by approximately an equivalent amount and could be as high as 21%. The approach can be applied in the design of news processes or in the revamping of existing ones

Depuis les années 60, la mousse présente un grand potentiel pour améliorer le balayage volumétrique par le gaz dans un réservoir pétrolier : des travaux de laboratoire et des essais sur champs montrent l’intérêt technique et économique de ce procédé. En effet, ses caractéristiques uniques, qui résultent de la dispersion du gaz dans un volume de liquide contenant des tensioactifs, en font un bon agent de réduction de mobilité du gaz, et par conséquent, ce qui conduit à la réduction des instabilités visqueuses issues du contraste de mobilité entre le gaz et l'huile en place. Par ailleurs, la mousse atténue les effets préjudiciables des hétérogénéités et de la ségrégation gravitaire sur la récupération, grâce à son comportement différent entres les faciès du réservoir. Dans la pratique industrielle, les simulateurs de réservoir s’attachent à ne modéliser que les effets de la mousse sur les déplacements en régime permanent, sans chercher à prédire son comportement dynamique régi par la génération, destruction et transport des lamelles (films minces) de mousse dans les milieux poreux. Suivant cette approche, la mousse est modélisée comme une réduction de mobilité du gaz, en particulier par le biais des perméabilités relatives, en utilisant des lois d'interpolations de paramètres impactant sa rhéologie, à savoir la vitesse et la qualité de la mousse, la saturation en huile, la concentration en tensioactif et la perméabilité du milieu poreux. Un tel modèle a l’avantage de la simplicité conceptuelle fondée sur l'extension des modèles de Darcy polyphasiques en n’utilisant que les paramètres d'écoulement mesurés au laboratoire, sans y intégrer le nouveau paramètre caractéristique de la mousse qui est la texture (densité des lamelles). Cependant, ces lois empiriques manquent de généralité et doivent être calibrées/ajustées à partir d’essais de laboratoire afin d'assurer la fiabilité des prévisions. Un modèle calibré à partir d’un nombre limité d’expériences comporte un degré d'incertitude et d’indétermination. L’ingénieur de réservoir a néanmoins recours à un tel modèle pour prédire et guider l’exploitation du gisement sur la base de ce procédé. D’où l’objectif principal de cette thèse qui consiste à améliorer le paramétrage des modèles de mousse empiriques via des lois mieux formulées et calibrées afin d’accroitre leur prédictivité. Dans cette thèse, nous avons établi les fondements physiques nécessaires pour valider les modèles empiriques en développant leur équivalence avec les modèles en texture assurée par des relations d’interdépendance entre les paramètres des deux approches. Cette équivalence a été montrée et étudiée en utilisant un modèle à lamelles pré-calibré de la littérature aux mesures de déplacements de mousse en régime permanent. Par ailleurs, ce parallèle avec les modèles en texture nous a permis de mettre au point une nouvelle procédure pour calibrer d'une manière fiable et déterministe les modèles empiriques. Cette procédure a été testée à partir des résultats d'expériences menées à IFPEN traduits en termes de texture en régime permanent. Enfin, nous avons proposé et interprété des lois d'échelle des paramètres du modèle de mousse en fonction de la perméabilité du milieu poreux, en analysant les paramètres des modèles calibrés sur des carottes de différentes perméabilités. L'importance de ces lois a été mise en évidence à travers des simulations sur une coupe de réservoir bi-couche. Les résultats de la simulation indiquent que les prévisions de performance d'un procédé à base de mousse, appliqué à un réservoir hétérogène, nécessitent une bonne connaissance des lois d'échelle des paramètres empiriques avec la perméabilité. / Conventional techniques of oil recovery consist in injecting water and/or gas into the geological formation to force out the oil. These methods may reveal ineffective because of high permeability contrasts, unfavorable mobility ratio between the driving fluid and the oil in place which generally generates viscous fingering, and gravity segregation. In this context, foam has shown a great potential to overcome all these detrimental effects, and thereafter, to improve the volumetric sweep efficiency. Still some key points need to be addressed regarding the predictive calculation of multiphase foam flow in porous media. Methods for modeling foam flow in porous media fall into two categories: population balance (PB) models and (semi)-empirical (SE) models. On the one hand, PB models describe foam lamellas transport in porous media and predict the evolution of foam microstructure as the result of pore-scale mechanisms of lamellas generation and destruction. Within this framework, the modeling of foam effects on gas mobility is directly related to foam texture (lamellas density) along with the effects of other parameters impacting its rheology such as foam quality and velocity, permeability of the porous media, surfactant concentration, etc. On the other hand, SE models are based on the extension of multiphase classical Darcy's model to describe foam flow in porous media, such that the foam texture effects are described indirectly through a multi-parameter interpolation function of parameters measured/observed in laboratory. Such formulation has to be calibrated from foam flow experimental data on a case-by-case basis, which can turn to be a cumbersome task. Furthermore, SE models involve uncertainty because they are not based on mechanistic laws driving lamellas transport in porous media, and their predictive capacity remains low as too few laboratory data are generally available for their calibration. Nonetheless, the reservoir engineer needs a reliable foam model in order to design, assess and optimize foam enhanced oil recovery processes for field application. Accordingly, this thesis aims at providing further insights into the topics related to the parameterization of (semi)-empirical models through better formulated and calibrated laws in order to improve their predictivity. In this work, we have established the physical basis necessary to validate the (semi)-empirical models. Indeed, we developed the equivalence between SE and PB models achieved through relationships between the parameters of these two modeling approaches (industrial and physical). The equivalence has been established and studied using a pre-calibrated PB model of the literature to fit steady-state foam measurements. In addition, this equivalence allowed us to develop a new procedure to calibrate the (semi)-empirical models in a reliable and deterministic way. This procedure was tested and validated using results from IFPEN core-flood experiments by translating them into steady-state texture measurements. Finally, we proposed scaling laws for empirical model parameters with the permeability of the porous media, by analyzing the fitted parameters on cores of different permeabilities. Different interpretations of the scaling laws are herein provided using theoretical models for lamellas stability. Then, their importance has been demonstrated through simulations on a two layer reservoir cross-section. The simulation results indicate that the predictions of foam flow in a heterogeneous reservoir require a good knowledge of the scaling laws of SE model parameters with permeability.