Orientador: Celso Kazuyuki Morooka / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica e Instituto de Geociências / Made available in DSpace on 2018-08-27T23:45:28Z (GMT). No. of bitstreams: 1 Pereira_LeandroAugustoGrandin_M.pdf: 2825767 bytes, checksum: 5cbfd5a04926d5bf83c780db67ca3a60 (MD5) Previous issue date: 2015 / Resumo: O desenvolvimento de campos marítimos de petróleo e gás natural tem se deslocado para águas cada vez mais profundas, ambientes cada vez mais hostis e áreas cada vez mais remotas. A utilização de soluções convencionais para desenvolver tais campos, especialmente o uso exclusivo de processamento primário em superfície e equipamentos elevação artificial instalados dentro de poços pode não justificar os investimentos. O processamento submarino tem aumentado a atratividade ou até viabilizando a produção de campos marítimos. Visto o aumento em sua utilização, os autores propuseram uma metodologia para selecionar conceitos de plantas submarinas para campos de petróleo e gás natural, utilizando informações disponíveis na literatura e suporte de especialistas em tecnologia submarina e modelagem de produção integrada. Uma menor contrapressão no poço produtor é uma potencial consequência do uso de processamento submarino, podendo tornar o perfil de produção mais atrativo. Como consequência, uma abordagem integrada considerando os estudos necessários para avaliar o escoamento dos fluidos de suas fontes iniciais até os destinos finais é necessária para se propor uma metodologia de seleção. Como alternativa à falta de estudos integrados comparando diferentes soluções de desenvolvimento em campos marítimos, informações de quatro desenvolvimentos comerciais que empregaram processamento submarino foram utilizadas para buscar a validação da metodologia. Os resultados destes estudos de caso sugerem que a metodologia é válida, entretanto não é claro que tais desenvolvimentos de produção utilizariam todas as fases propostas / Abstract: The development of offshore oil and natural gas fields has been moving to deeper waters, harsher environments and more remote areas. The use of conventional solutions to develop such fields, especially sole use of surface processing or downhole artificial lift methods, may not justify the investments. Subsea processing has been increasing the attractiveness or even enabling offshore field developments. Given the increase in its use, the authors proposed a methodology to select concepts of subsea processing plants for oil and natural gas fields, using information available in the literature as well as support from specialists in subsea technology and integrated production modelling. Higher drawdown in producer wells is a potential consequence of the use of subsea processing, therefore it may positively impact the production profile. As a consequence, an integrated approach comprising all the studies necessary to assess the flow between the initial sources and the final destinations is necessary to propose a selection methodology. As an alternative to overcome the lack of integrated studies comparing different development solutions in offshore fields, information from four commercial developments that employed subsea processing was used to seek methodology validation. The results of these four case studies suggest that the methodology is valid, although it is not clear if such production developments would utilize all phases proposed / Mestrado / Explotação / Mestra em Ciências e Engenharia de Petróleo

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Atomization of fuel is essential in controlling combustion inside a direct injection engine. Controlling combustion helps in reducing emissions and boosting efficiency. Cavitation is one of the factors that significantly affect the nature of spray in a combustion chamber. Typical fuel injector nozzles are small and operate at a very high pressure, which limit the study of internal nozzle behavior. The time and length scales further limit the experimental study of a fuel injector nozzle. Simulating cavitation in a fuel injector will help in understanding the phenomenon and will assist in further development. The construction of any simulation of cavitating injector nozzles begins with the fundamental assumptions of which phenomena will be included and which will be neglected. To date, there has been no consensus about whether it is acceptable to assume that small, high-speed cavitating nozzles are in thermal or inertial equilibrium. This diversity of opinions leads to a variety of modeling approaches. If one assumes that the nozzle is in thermal equilibrium, then there is presumably no significant delay in bubble growth or collapse due to heat transfer. Heat transfer is infinitely fast and inertial effects limit phase change. The assumption of inertial equilibrium means that the two phases have negligible slip velocity. Alternatively, on the sub-grid scale level, one may also consider the possibility of small bubbles whose size responds to changes in pressure. Schmidt et al. developed a two dimensional transient homogeneous equilibrium model which was intended for simulating a small, high speed nozzle flows. The HEM uses the assumption of thermal equilibrium to simulate cavitation. It assumes the two-phase flow inside a nozzle in homogeneous mixture of vapor and liquid. This work presents the simulation of high-speed nozzle, using the HEM for cavitation, in a multidimensional and parallel framework. The model is extended to simulate the non-linear effects of the pure phase in the flow and the numerical approach is modified to achieve stable result in multidimensional framework. Two-dimensional validations have been presented with simulation of a venturi nozzle, a sharp nozzle and a throttle from Winklhofer et al. Three-dimensional validations have been presented with simulation of ‘spray A’ and ‘spray H’ injectors from the Engine Combustion Network. The simulated results show that equilibrium assumptions are sufficient to predict the mass flow rate and cavitation incidence in small, high-speed nozzle flows.

The huge energy demand of our society is causing fossil fuel resources to diminish rapidly. Therefore, it is critical to search for alternative energy resources. Biomass is currently both abundant and inexpensive. Biofuels (fuels produced from biomass) have the potential to replace fossil fuels if a cost effective process can be develop to convert biomass into fuels. Catalytic fast pyrolysis is a technology that can convert biomass into gasoline ranged aromatics in a single step. By heating biomass quickly to an intermediate temperature, biomass will thermally decompose into small molecules which can fit into zeolite catalyst pores. Inside the catalyst pores, these small molecules undergo a series of reactions where aromatics are formed along with olefins, CO, CO2, CH4 and water. Gallium promoted ZSM-5 catalyst has been shown to promote small alkanes aromatization, thus it has the potential to increase aromatic yield in catalytic fast pyrolysis process. The focus of the thesis is to study the behavior of catalyst fast pyrolysis of biomass over Gallium promoted catalyst, and explore various ways to utilize the gas phase olefins to increase the aromatic yield. [CG1] The effect of reaction parameters (temperature, weight hourly space velocity, and fluidized gas velocity) on catalytic fast pyrolysis of biomass with Ga/ZSM-5 were studied in a fluidized bed reactor using pine saw dust as the biomass feed. The product distribution and hydrocarbon selectivity are shown to be a strong function of temperature and weight hourly space velocity. Compared to ZSM-5 catalyst at the same reaction conditions, Ga/ZMS-5 has been shown to increase the aromatic yield by 40%. Olefins can be recycled back to the CFP fluidized bed reactor to further increase the aromatic yield. The olefin co-feeding with pine saw dust experiments indicates that co-feeding with propylene can increase the aromatic yield, however, co-feeding with ethylene will cause a decrease in aromatic yield. In both co-feeding experiments, an increase in the amount of coke formed was also observed. Besides a simple olefin recycle, another possible way to utilize these olefins, while avoiding the high cost to separate them from other gas phase products (CO, CO2 and CH4),is adding a secondary alkylation unit after the fluidized bed reactor. The alkylation unit could provide a way to produce additional ethylbenzene after the main CFP process. Three zeolite catalysts (ZSM-5, Y-zeolite and Beta zeolite) were tested in the alkylation unit, and ZSM-5 catalyst shows the highest activity and selectivity in the alkylation of benzene and ethylene.

Hydraulic fracture is a well-developed and widely used technology across petroleum upstream operations. The process involves the high-pressure injection of ‘fracking fluid’, mainly water containing proppants and thickening agents, into wells to form underground artificial fractures. The fracking fluid extends forward and supports those fractures to create diversion channels which lead to increased production. Therefore, it is of great significance to improve the permeability of the fractured formation, which leads to increased oil and gas production, and improved efficiency of oil and gas wells. Due to the importance of conductivity in such operations, the quality of s proppants are a critical factor affecting the fracturing efficiency and stimulation. For improvement of proppant, high strength often comes at the cost of increased density. During fracturing stimulation, it demands a higher flow rate, viscosities, and pumping pressure. It also results in the consumption of a significant amount of power, fresh water and produces more greenhouse gas and chemical pollution in the formation and the well site. This study investigated the production of an Ultra-Lightweight Proppant made by Graphene Aerogel (GA) and Epoxy Resin (ER) composite. GA with graphene as the basic structural unit is a low-density solid material with a high specific surface area, abundant nanoporous structure and good mechanical properties. Cured ER has the characteristics of small deformation and shrinkage, good dimensional stability, and high hardness. ER is one of the commonly used substrates in resin matrix composites. The main research contents of this study are as follows: 1. Using graphene oxide solution as a precursor to prepare graphene hydrogels, then make graphene aerogels through supercritical drying or freeze-drying. The graphene aerogel was placed in ER, followed by immersion in a vacuum environment, and then thermally cured to obtain a graphene aerogel-epoxy composite. The prepared GA has a network microstructure; the ER combined with the aerogel, and the composite material have good mechanical properties, strength is about 50 MPa. Specific gravity is 1.2, 55% lighter than silica sand and 63% lighter than ceramic proppant. 2. Spherical GA were produced using a droplet freezing method, which was combined with ER to create spherical fracturing proppants. The graphene aerogel-epoxy resin composite compressive strength is about 30 MPa, which is significantly higher than silica sand. The sphericity is about 0.9, better than silica sand (0.6-0.8) and same as ceramic proppant (0.9). its crushing rate is better than intermediate-density ceramic at 50, 70, and 100 MPa. The conductivity test showed that this new proppant was 30% and 50% higher than traditional silica sand and ceramic. 3. In the Field study, collecting core sampling and fluid analysis results to evaluate the porosity formation, permeability, fluid density and oil viscosity. Analyzation of the fracturing treatment data for the pressure testing data within the current field. Using the test results of the graphene aerogel spherical epoxy proppant (GAS-EP) modelling conducted for fracturing half-length and fracturing width, the result showing the new proppant can improve the fracturing length by 35% and increase oil Estimated ultimate recovery (EUR) volume about 10K bbl. 4. Based on field data and modelling results, horizontal well decline curve were generated for each scenario, using economic indicators, such as NPV value, payback time and others estimated that the break-even price of GAS-EP will be $2800/t. 5. Discuss the environmental benefits, using GAS-EP could reduce chemical additives by 4600L, reduce freshwater consumption 190m³ and reduce CO₂ emission 1.3 tons for a single fracturing stimulation. The study resulted in the production of a novel proppant with improved properties compared to the conventional materials. The results of this study provide a better understanding of the novel proppant properties and concluded that the novel proppant could safely use in the petroleum industry for enhance hydrocarbon recovery and significant environmental and economic benefits.

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Deoiling of petroleum wastewater is a major concern in petroleum process engineering. The conventional design procedure for deoiling systems consists of nine consecutive stages involving different people or groups. This thesis considers reengineering the conventional procedure, with the aim of increasing the efficiency of the process and productivity of people involved. The thesis then investigates the development of the appropriate computer support tools for the new procedure. The reengineering of the procedure is based on concepts proposed by Hammer (1990). The resulting procedure consists of four stages, where parallelism of the different tasks in the conventional procedure is explicitly considered. A model of the new procedure is described in UML (Unified Modelling Language). The advantage of using UML instead of using just natural language description is that UML uses graphical representation that is easy to use and less prone to ambiguity. Based on the new procedure, a decision support system called CODES (Conceptual DEsign of deoiling Systems) was designed and implemented. CODES supports the stages of wastewater assessment, equipment options at different locations, treatment disposal options and recommendations for final process configuration. Two Case Studies using operating field data are reported. The Case Studies using CODES proved to be straightforward to use and produced appropriate comments on the performance of the existing designs and proposed alternatives to satisfy the design requirements. CODES results agreed with knowledge from previous plant trials. The contribution of this thesis to the deoiling design process is twofold. Firstly, a critical review of the conventional procedure has resulted in a new one, which has potential benefits of improving a company's efficiency by reducing the number of people and activities involved, and shortening the design time. Secondly, the feasibility of applying the new procedure and CODES is successfully demonstrated through the case studies. Limitations and areas of extensions are also identified.

High-temperature, high-pressure (HTHP) conditions are exemplified in ultra-deep petroleum reservoirs and can be exhibited within diesel engines. Accurate pure component hydrocarbon data is essential in understanding the overall behavior of petroleum and diesel fuel at these conditions. The present study focuses on the HTHP properties of toluene since this hydrocarbon is frequently used to increase the octane rating of gasoline and toluene occurs naturally in crude oil. In this thesis experimental densities and viscosity are presented to 535 K and 300 MPa extending the database of toluene viscosity data to higher temperature than previous studies. The data is correlated to a Tait-like equation and a Padѐ approximate in conjunction with a single mapping of the isotherms. Free-volume theory and a superposition of the viscosity in relation to the Leonnard-Jones repulsive force are both used to model the toluene viscosity data. It was found that the data are in good agreement with the available literature data.