• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 483
  • 58
  • 7
  • 1
  • 1
  • Tagged with
  • 579
  • 579
  • 210
  • 70
  • 66
  • 56
  • 38
  • 31
  • 29
  • 29
  • 23
  • 22
  • 21
  • 21
  • 21
  • 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.
451

Using reservoir simulation to constrain the estimation of dynamic properties from 4D seismic = Uso da simulação de reservatórios para restringir a estimativa de propriedades dinâmicas a partir da sísmica 4D / Uso da simulação de reservatórios para restringir a estimativa de propriedades dinâmicas a partir da sísmica 4D

Davólio, Alessandra, 1980- 23 August 2018 (has links)
Orientadores: Denis José Schiozer, Célio Maschio / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica e Instituto de Geociências / Made available in DSpace on 2018-08-23T20:38:54Z (GMT). No. of bitstreams: 1 Davolio_Alessandra_D.pdf: 20299340 bytes, checksum: 39bd0e5f79603d95c1cb4c74b2616103 (MD5) Previous issue date: 2013 / Resumo: O foco deste trabalho é usar dados de engenharia de reservatórios gerados através da simulação de fluxos para melhorar a interpretação quantitativa da sísmica 4D. A ideia é usar os conhecimentos de engenharia para minimizar possíveis informações incorretas geradas pela sísmica 4D, antes de usá-la para atualizar modelos de simulação de reservatórios em um procedimento de ajuste de histórico. Neste trabalho a integração entre estes dois conjuntos de dados é feita no domínio da pressão e saturação. Dessa forma, a primeira parte do trabalho apresenta uma metodologia para estimar variações de pressão e saturação a partir da sísmica 4D através de um procedimento de inversão petro-elástica. Este procedimento pode ser visto como uma ferramenta para aplicar a metodologia de integração da segunda parte, que é uma das principais contribuições deste trabalho. A metodologia de integração usa múltiplos modelos de simulação para restringir a estimativa de pressão e saturação a partir da sísmica 4D. Como resultado, observaram-se mapas menos ruidosos que permitem, portanto, uma melhor interpretação das variações ocorridas no reservatório. Seguindo a sequencia tradicional de trabalho, o mapa de saturação estimado foi então usado como dado de entrada em um processo de ajuste de histórico apresentado na terceira parte da tese. Foi mostrado que o procedimento de ajuste gera melhores resultados quando o dado de entrada, neste caso mapa de saturação, respeita o balanço de massa, o que não acontecia para os dados considerados. Assim, uma metodologia para calibrar o volume de água injetada associado ao mapa de saturação gerado pela sísmica 4D é apresentada na última parte do trabalho, que é outra contribuição importante a se destacar. Para melhor controlar os resultados de todas as metodologias aqui apresentadas foram usados dados sintéticos em todo o trabalho. Embora resultados satisfatórios tenham sido observados para este conjunto de dados, é importante destacar que as principais contribuições deste trabalho não são apenas os resultados observados, mas as metodologias propostas, que apresentam uma perspectiva inovadora para integração entre dados de sísmica 4D e engenharia de reservatórios / Abstract: The focus of this work is to use reservoir engineering data from numerical flow simulation to improve the quantitative interpretation of 4D seismic signals. The idea is to use engineering knowledge to minimize possible incorrect information provided by 4D seismic before using it to update reservoir simulation models in a history matching procedure. In this work the integration between the two dataset is done in the pressure and saturation domain. So, the first part of the work presents a methodology to estimate pressure and saturation changes from 4D seismic through a petro-elastic inversion procedure. This procedure can be seen as a tool to apply the integration methodology of the second part which is one of the main contributions of this work. The integration methodology uses multiple simulation models to constrain the estimation of pressure and saturation from 4D seismic. As a result, less noisy maps were obtained, allowing a better interpretation of the reservoir changes. Following the traditional sequence, the estimated saturation map is then used as input to the history matching process presented in the third part of the work. It was shown that the history matching procedure provides better results if the input data, in this case the saturation map, respects the expected mass balance, which was not the case for the dataset considered. Thus, a methodology to calibrate the volume of injected water associated to the saturation map provided by 4D seismic is presented in the last part of the work, which is another important contribution to be highlighted. To better control the results of all the methodologies here presented, a synthetic dataset was used in the entire work. Although satisfactory results were observed for this dataset, it is important to highlight that the main contributions of this work are not only the results, but the methodologies proposed, that present an innovative perspective for 4D seismic and reservoir engineering data integration / Doutorado / Reservatórios e Gestão / Doutora em Ciências e Engenharia de Petróleo
452

Metodologia de análise de integridade para projetos de poço de desenvolvimento da produção / A methodology for production development wells integrity analysis

Da Fonseca, Tiago Cardoso, 1981- 21 August 2018 (has links)
Orientadores: José Ricardo Pelaquim Mendes, Kazuo Miura / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica e Instituto de Geociências / Made available in DSpace on 2018-08-21T13:11:36Z (GMT). No. of bitstreams: 1 DaFonseca_TiagoCardoso_M.pdf: 2105397 bytes, checksum: 938187b300de7b315fa5e2dcca4fef13 (MD5) Previous issue date: 2012 / Resumo: Integridade de poço pode ser entendida como sua capacidade de evitar vazamentos para o meio ambiente e é uma importante característica de um poço de petróleo. Uma das formas de evitar vazamentos durante a fase de produção é realizar intervenções de manutenção que conservem os poços em situações seguras e com barreiras de segurança sobressalentes. A previsão de custos relativos às intervenções para manutenção deve ser levada em conta nas fases iniciais dos projetos de Desenvolvimento da Produção, quando se planeja e se avalia técnica e economicamente a campanha de construção de poços. Este trabalho apresenta uma metodologia para análise de integridade de poços de Desenvolvimento da Produção que considera a existência de estados intermediários, onde não há perda de integridade, mas o sistema poço encontra-se degradado, fundamentando-se nos conceitos de Conjuntos Solidários de Barreiras (CSB) propostos por Miura (2004) e em técnicas de Engenharia de Confiabilidade. A metodologia pode ser utilizada na previsão de recursos para as intervenções de manutenção de uma campanha de construção e operação de poços. Através do tempo esperado para falha de cada um dos CSB presentes na configuração de completação é possível se estimar quando o estado de integridade do poço passará a depender de um único Conjunto Solidário de Barreiras e qual a expectativa para que haja vazamento (ausência de CSB) / Abstract: Well integrity may be defined as its capability to prevent leaks to the environment and is therefore a very important feature for oil and gas wells. One way to avoid leaks during the well operation is to perform maintenance interventions, seeking to keep redundancy in the well's safety barriers. Cost assessment regarding the wells maintenance interventions shall be done during the initial phases of the Production Development project, when the wells construction campaign is both technically and economically evaluated. This work presents a methodology for petroleum wells integrity analysis considering the existence of intermediate stages, when the integrity has not been lost but the well is considered to be in a degraded status. The method is based on the Barrier Integrated Sets (BIS), proposed by Miura (2004, in Portuguese) and described by Miura et al. (2006 [1]), and on Reliability Engineering techniques. The methodology may be used for maintenance interventions resource assessment considering a well construction campaign. Through the computation of the mean time to failure of each BIS identified in the completion configuration it is possible to estimate when the well is in a degraded status, relying in a single Barrier Integrated Set and well the well is expected to leak (no BIS) / Mestrado / Explotação / Mestre em Ciências e Engenharia de Petróleo
453

The Development of the Oil Industry in Cooke County

Porter, Amy T. 08 1900 (has links)
"This paper is the result of a study of the oil industry in Cooke County Texas. Consideration was given to the following factors: the physiography and geology of Cooke County, the first oil developments, opening of various fields, the Tydal Refinery, and the benefits of the oil industry to the county in terms of employment, busines establishments, schools, and social efforts. Both persona and documentary source were utilized for obtaining data on the present problem. Primary sources included statements made by land owners of Cooke County, oil operators, drillers, refinery personnel, business men, civic leaders, and the superintendents of schools, both in Gainesville, Texas, and in Cooke County. Secondary sources included newspapers, oil publications, and books on geology and the oil industry. "-- leaf vi.
454

Geomechanical Characterization of Marcellus Shale

Villamor Lora, Rafael 01 January 2015 (has links)
Given their potential applications for a number of engineering purposes, the geomechanics of shale reservoirs is becoming one of the most important issues in modern geomechanics. Borehole stability modeling, geophysics, shale oil and shale gas reservoirs, and underground storage of CO2 and nuclear waste are some of these potential applications to name a few. The growing interest in these reservoirs, as a source for hydrocarbons production, has resulted in an increasing demand for fundamental material property data. Laboratory analysis and constitutive models have shown that rock elastic and deformational properties are not single-value, well-defined parameters for a given rock. Finding suitable values for these parameters is of vital importance in many geomechanical applications. In this thesis an extensive experimental program to explore geomechanical properties of shale was developed. A series of triaxial tests were performed in order to evaluate the elasticity, yielding, and failure response of Marcellus shale specimens as a function of pressure, temperature, and bedding angle. Additional characterization includes mineralogy, porosity, and fabric. Rock samples used in this study came from three different locations and depths: one actual reservoir (~7,500 ft. deep), and two outcrops (~300 ft. and ~0 ft. deep).
455

MEASUREMENTS AND MODELING OF HYDROCARBON MIXTURE FLUID PROPERTIES UNDER EXTREME TEMPERATURE AND PRESSURE CONDITIONS

Bamgbade, Babatunde A 01 January 2015 (has links)
Knowledge of thermodynamic fluid properties, such as density and phase behavior, is important for the design, operation, and safety of several processes including drilling, extraction, transportation, and separation that are required in the petroleum. The knowledge is even more critical at extreme temperature and pressure conditions as the search for more crude oil reserves lead to harsher conditions. Currently, there is dearth of experimental data at these conditions and as such, the predictive capability of the existing modeling tools are unproven. The objective of this research is to develop a fundamental understanding of the impact of molecular architecture on fluid phase behavior at temperatures to 523 K (250 °C) and pressures to 275 MPa (40,000 psi). These high-temperature and high-pressure (HTHP) conditions are typical of operating conditions often encountered in petroleum exploration and recovery from ultra-deep wells that are encountered in the Gulf of Mexico. This PhD study focuses on the fluid phase behavior of a low molecular weight compound, two moderately high molecular weight compounds, three asymmetric binary mixtures of a light gas and a heavy hydrocarbon compound with varying molecular size. The compounds are selected to represent the family of saturated compounds found in typical crude oils. Furthermore, this study reports experimental data for two "dead" crude oil samples obtained from the Gulf of Mexico and their mixtures with methane from ambient to HTHP conditions. A variable-volume view cell coupled with a linear variable differential transformer is used to experimentally measure the high-pressure properties of these compounds and mixtures. The reported density data compare well to the limited available data in the literature with deviations that are less than 0.9%, which is the experimental uncertainty of the density data reported in this study. The phase behavior and density data obtained in this study are modeled using the Peng-Robinson (PR), the volume-translated (VT) PR, and the Perturbed-Chain Statistical Associating Fluid Theory (PC-SAFT) equations of state (EoS). The EoS pure component parameters, typically obtained from the open literature, are derived from fitting the particular EoS to, critical point, or to vapor pressure and saturated liquid density data, or to HTHP density data. For the density data reported here, the PREoS provided the worst predictions, while the VT-PREoS gives an improved performance as compared to the PREoS. However, the PC-SAFT EoS provided the best HTHP density predictions especially when using HTHP pure component parameters. The situation is however reversed in the modeling performance for the phase behavior data whereby the PC-SAFT EoS with HTHP parameters provided the worst vapor-liquid equilibria predictions. Better predictions are obtained with the PC-SAFT EoS when using parameters obtained from fit of the vapor pressure data and is comparable to the PREoS predictions. This reversal in performance is not surprising since the phase behavior data occur at moderately low pressures. The performance of the PC-SAFT EoS is extended to the experimental density data reported for the dead crude oil samples and their mixtures with methane. The PC-SAFT EoS with either set of pure component parameters yield similar predictions that are within 3% of the reported crude oil density data. However, when using the HTHP parameters, the PC-SAFT gives a good representation of the slope of experimental data, which is crucial in the calculation of second-derivative properties such has isothermal compressibility. The PC-SAFT EoS is also employed to model the crude oil HTHP density data for both the dead crude oils and their mixtures with methane using correlations for both the Low-P parameters and the HTHP parameters. The Low-P parameters are derived from fitting the PC-SAFT EoS to pure compound vapor pressure and saturated liquid density data, while the HTHP parameters are obtained from fitting the PC-SAFT EoS to pure compound HTHP liquid density data. Interestingly, the PC-SAFT EoS with the Low-P parameters provided better HTHP density predictions that are within 1.5% of the experimental data for the dead oils than the HTHP parameters that are within 2 to 4% of the data. Density predictions for the dead oil mixtures with methane are however comparable for both sets of parameters and are within 1% on average. However, the PC-SAFT EoS with HTHP parameters clearly provided better representation of the isothermal property, a derivative property obtained from density data, within 10% while predictions with the Low-P parameters can be as high as 37%. The successful completion of the thesis work expands the current knowledge base of fluid phase behavior at the extreme operating conditions encountered by engineers in the petroleum industries. Furthermore, the reported HTHP experimental data also provide a means to scientists and researchers for the development, improvement, and validation of equations with improved modeling performance.
456

Productivity enhancement in a combined controlled salinity water and bio-surfactant injection projects

Udoh, Tinuola H. January 2018 (has links)
No description available.
457

Effect of using Organosilane with Crumb Rubber Modified Hot Mix Asphalt Mixtures

January 2018 (has links)
abstract: Crumb rubber use in asphalt mixtures by means of wet process technology has been in place for several years in the United States with good performance record; however, it has some shortcomings such as maintaining high mixing and compaction temperatures in the field production. Organosilane (OS), a nanotechnology chemical substantially improves the bonding between aggregate and asphalt by modifying the aggregate structure from hydrophilic to hydrophobic contributing to increased moisture resistance of conventional asphalt mixtures. Use of Organosilane also reduces the mixing and compaction temperatures and facilitates similar compaction effort at lower temperatures. The objective of this research study was first to perform a Superpave mix design for Crumb Rubber Modified Binder (CRMB) gap-graded mixture with and without Organosilane; and secondly, analyse the performance of CRMB mixtures with and without Organosilane by conducting various laboratory tests. Performance Grade (PG) 64-22 binder was used to create the gap-graded Hot Mix Asphalt (HMA) mixtures for this study. Laboratory tests included rotational viscometer binder test and mixtures tests: dynamic modulus, flow number, tensile strength ratio, and C* fracture test. Results from the tests indicated that the addition of Organosilane facilitated easier compaction efforts despite reduced mixing and compaction temperatures. Organosilane also modestly increased the moisture susceptibility and resistance to crack propagation yet retaining equal rutting resistance of the CRMB mixtures. / Dissertation/Thesis / Masters Thesis Civil, Environmental and Sustainable Engineering 2018
458

UNDERSTANDING INHIBITION OF A BIODESULFURIZATION ENZYME TO IMPROVE SULFUR REMOVAL FROM PETROLEUM

Yu, Yue 01 January 2018 (has links)
The biodesulfurization 4S-pathway is a promising complementary enzymatic approach to remove sulfur from recalcitrant thiophenic derivatives in petroleum products that remain from conventional hydrodesulfurization method without diminishing the calorific value of oil. The final step of this pathway involves the carbon-sulfur bond cleavage from HBPS, and the production of the final products 2-hydroxybiphenyl (HBP) and sulfite, has been recognized as the rate-limiting step, partially as a result of product inhibition. However, the mechanisms and factors responsible for product inhibition in the last step have not been fully understood. In this work, we proposed a computational investigation using molecular dynamic simulations and free energy calculations on 2’-hydroxybiphenyl-2-sulfinate (HBPS) desulfinase (DszB) with different bound ligands as well as different solvent conditions to develop a fundamental understanding of the molecular-level mechanism responsible for product inhibition. Based on available crystal structures of DszB and biochemical characterization, we proposed a “gate” area close to substrate binding site of DszB is responsible for ligand egress and plays a role in product inhibition. We have conducted biphasic molecular dynamic simulations to evaluate the proposed gate area functionality. Non-bonded interaction energy analysis shows that hydrophobic residues around the gate area produce van der Waals interactions inhibiting translocation through the gate channel, and therefore, the molecules are easily trapped inside the binding site. Umbrella sampling molecular dynamics was performed to obtain the energy penalty associated with gate conformational change from open to close, which was 2.4 kcal/mol independent of solvent conditions as well as bound ligands. Free energy perturbation calculations were conducted for a group of six selected molecules bound to DszB. The selections were based on functional group representation and to calculate binding free energies that were directly comparable to experimental inhibition constants, KI. Our work provides a fundamental molecular-level analysis on product inhibition for the biodesulfurization 4S-pathway.
459

Petroleum well costs

Leamon, Gregory Robert, Petroleum Engineering, Faculty of Engineering, UNSW January 2006 (has links)
This is the first academic study of well costs and drilling times for Australia???s petroleum producing basins, both onshore and offshore. I analyse a substantial database of well times and costs sourced from government databases, industry and over 400 recent well completion reports. Three well phases are studied - Pre-Spud, Drilling and Completion. Relationships between well cost factors are considered, including phase time, phase cost, daily cost, rig day rate, well depth, basin, rig type, water depth, well direction, well objective (e.g. exploration), and type of completion (P&A or producer). Times and costs are analysed using scatter plots, frequency distributions, correlation and regression analyses. Drilling times are analysed for the period 1980 to 2004. Well time and variability in well time tend to increase exponentially with well depth. Technical Limits are defined for both onshore and offshore drilling times to indicate best performance. Well costs are analysed for the period 1996 to 2004. Well costs were relatively stable for this period. Long term increases in daily costs were offset to some extent by reductions in drilling times. Onshore regions studied include the Cooper/Eromanga, Surat/Bowen, Otway and Perth Basins. Offshore regions studied include the Carnarvon Basin shallow and deepwater, the Timor Sea and Victorian Basins. Correlations between regional well cost and well depth are usually high. Well costs are estimated based on well location, well depth, daily costs and type of completion. In 2003, the cost of exploration wells in Australia ranged from A$100,000 for shallow coal seam gas wells in the Surat/Bowen Basins to over A$50 million for the deepwater well Gnarlyknots-1 in the Great Australian Bight. Future well costs are expected to be substantially higher for some regions. This study proposes methods to index historical daily costs to future rig day rates as a means for estimating future well costs. Regional well cost models are particularly useful for the economic evaluation of CO2 storage sites which will require substantial numbers of petroleum-type wells.
460

Analysing Complex Oil Well Problems through Case-Based Reasoning

Abdollahi, Jafar January 2007 (has links)
<p>The history of oil well engineering applications has revealed that the frequent operational problems are still common in oil well practice. Well blowouts, stuck pipes, well leakages are examples of the repeated problems in the oil well engineering industry. The main reason why these unwanted problems are unavoidable can be the complexity and uncertainties of the oil well processes. Unforeseen problems happen again and again, because they are not fully predictable, which could be due to lack of sufficient data or improper modelling to simulate the real conditions in the process. Traditional mathematical models have not been able to totally eliminate unwanted oil well problems because of the many involved simplifications, uncertainties, and incomplete information. This research work proposes a new approach and breakthrough for overcoming these challenges. The main objective of this study is merging two scientific fields; artificial intelligence and petroleum engineering in order to implement a new methodology.</p><p>Case-Based Reasoning (CBR) and Model-Based Reasoning (MBR), two branches of the artificial intelligence science, are applied for solving complex oil well problems. There are many CBR and MBR modelling tools which are generally used for different applications for implementing and demonstrating CBR and MBR methodologies; however, in this study, the Creek system which combines CBR and MBR has been utilized as a framework. One specific challenging task related to oil well engineering has been selected to exemplify and examine the methodology. To select a correct candidate for this application was a challenging step by itself. After testing many different issues in the oil well engineering, a well integrity issue has been chosen for the context. Thus, 18 leaking wells, production and injection wells, from three different oil fields have been analysed in depth. Then, they have been encoded and stored as cases in an ontology model given the name Wellogy.</p><p>The challenges related to well integrity issues are a growing concern. Many oil wells have been reported with annulus gas leaks (called internal leaks) on the Norwegian Continental Shelf (NCS) area. Interventions to repair the leaking wells or closing and abandoning wells have led to: high operating cost, low overall oil recovery, and in some cases unsafe operation. The reasons why leakages occur can be different, and finding the causes is a very complex task. For gas lift and gas injection wells the integrity of the well is often compromised. As the pressure of the hydrocarbon reserves decreases, particularly in mature fields, the need for boosting increases. Gas is injected into the well either to lift the oil in the production well or to maintain pressure in the reservoir from the injection well. The challenge is that this gas can lead to breakdown of the well integrity and cause leakages. However, as there are many types of leakages that can occur and due to their complexity it can be hard to find the cause or causal relationships. For this purpose, a new methodology, the Creek tool, which combines CBR and MBR is applied to investigate the reasons for the leakages. Creek is basically a CBR system, but it also includes MBR methods.</p><p>In addition to the well integrity cases, two complex cases (knowledge-rich cases) within oil well engineering have also been studied and analysed through the research work which is part of the PhD. The goal here is to show how the knowledge stored in two cases can be extracted for the CBR application.</p><p>A model comprising general knowledge (well-known rules and theories) and specific knowledge (stored in cases) has been developed. The results of the Wellogy model show that the CBR methodology can automate reasoning in addition to human reasoning through solving complex and repeated oil well problems. Moreover, the methodology showed that the valuable knowledge gained through the solved cases can be sustained and whenever it is needed, it can be retrieved and reused. The model has been verified for unsolved cases by evaluating case-matching results. The model gives elaborated explanations of the unsolved cases through the building of causal relationships. The model also facilitates knowledge acquisition and learning curves through its growing case base.</p><p>The study showed that building a CBR model is a rather time-consuming process due to four reasons:</p><p>1. Finding appropriate cases for the CBR application is not straightforward</p><p>2. Challenges related to constructing cases when transforming reported information to symbolic entities</p><p>3. Lack of defined criteria for amount of information (number of findings) for cases</p><p>4. Incomplete data and information to fully describe problems of the cases at the knowledge level</p><p>In this study only 12 solved cases (knowledge-rich cases) have been built in the Wellogy model. More cases (typically hundreds for knowledge-lean cases and around 50 for knowledge-rich cases) would be required to have a robust and efficient CBR model. As the CBR methodology is a new approach for solving complex oil well problems (research and development phase), additional research work is necessary for both areas, i.e. developing CBR frameworks (user interfaces) and building CBR models (core of CBR). Feasibility studies should be performed for implemented CBR models in order to use them in real oil field operations. So far, the existing Wellogy model has showed some benefits in terms of; representing the knowledge of leaking well cases in the form of an ontology, retrieving solved cases, and reusing pervious cases.</p>

Page generated in 0.1364 seconds