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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.
11

[en] PARAFFIN DEPOSITION IN OIL PRODUCTION LINE / [pt] DEPOSIÇÃO DE PARAFINA EM LINHA DE PRODUÇÃO DE PETRÓLEO

FLAVIO SANT ANNA RIBEIRO 12 March 2018 (has links)
[pt] O presente trabalho visa a obtenção de um melhor conhecimento dos mecanismos de deposição de parafina em linhas de produção de petróleo, a fim de auxiliar nas atividades de manutenção preditiva, e de fornecer subsídios para o estudo da viabilidade econômica da exploração de campos petrolíferos. Os dados experimentais obtidos foram utilizados para calibrar o simulador numérico desenvolvido pela PUC-Rio. Experiências de deposição para várias condições e óleos foram realizados. O regime de escoamento foi sempre monofásico (líquido). Foi realizada uma comparação entre os dados experimentais e resultados numéricos correspondentes, tendo-se observado uma boa concordância entre ambos. / [en] This work aims at a better understanding of the paraffin deposition mechanism in oil production lines. This knowledge can be very helpful in maintenance activities and to perform economical feasibility studies of exploration of oil fields. Experimental results were used to adjust e numerical simulator developed at PUC-Rio to a number of different oils. Deposition experiments for several conditions and oils were performed. The flow regime imposed was a liquid single-phase. Comparisons between experimental results and numerical predictions showed reasonable agreement.
12

Estabilidade linear para intermitência severa em sistemas água-ar. / Linear stability for severe slugging in air-water systems.

Azevedo, Gabriel Romualdo de 15 December 2017 (has links)
Apresenta-se um modelo matemático que avalia numericamente a estabilidade do estado estacionário para escoamentos água-ar em sistemas pipeline-riser de geometria variável. Uma análise a partir da teoria de estabilidade linear é aplicada a um modelo matemático adequado ao escoamento água-ar no sistema pipeline-riser. O modelo considera equações de continuidade para a fase líquida e para a fase gasosa, admite-se escoamento unidimensional e em condição isotérmica. O líquido é considerado incompressível enquanto que a fase gasosa é considerada um gás ideal. Admite-se uma equação de momento simplificada para mistura onde despreza-se a inércia (NPW - Modelo No Pressure Wave) e o padrão de escoamento local é definido com base nas condições do escoamento e na inclinação local. Assim, a intermitência severa é controlada principalmente pela gravidade no riser e pela compressibilidade do gás no pipeline. Tanto a correlação de fluxo de deriva quanto o cálculo da queda de pressão por atrito, adotados como lei de fechamento do modelo, são determinados em função do padrão de escoamento. Injeção de gás e válvula de choke são consideradas, respectivamente, na base e no topo do riser. O modelo é aplicado à sistemas pipeline-riser com escoamento água-ar citados na literatura. Os resultados da análise de estabilidade linear numérica são comparados aos resultados experimentais e numéricos apresentando uma excelente concordância. / A mathematical model that numerically evaluates the stability of the stationary state for hilly terrain air-water flows systems is presented. Numerical linear stability analysis is performed to a suitable mathematical model for the two-phase flows in a pipeline-riser system. The mathematical model considers the continuity equations for the liquid and gas phases, one-dimensional flow and isothermal conditions. The liquid is assumed incompressible while the gas phase is considered as an ideal gas. A simplified momentum equation for the mixture, neglecting inertia (NPW - No pressure wave model) is considered and the local flow pattern is defined based on the flow conditions and the local inclination. In this way, severe slugging is controlled mainly by gravity in the riser and compressibility in the pipeline. The void fraction and friction pressure drop, utilized as closure laws, are determined based on the local flow pattern. Gas injection at the bottom of the riser and a choke valve at the top are considered. The model is applied to air-water pipeline-riser systems reported in the literature. Numerical linear stability analysis results are compared with experimental and numerical results reported in the literature with excellent agreement.
13

Sistema baseado em medidor de pressão diferencial para determinação em linha de vazões de produção em poços de petróleo. / System based on differential pressure device for in ine determination of production flow rate in oil wells.

Elson Francisco da Paz 17 December 2010 (has links)
A indústria de petróleo e gás tem trabalhado para o desenvolvimento de métodos que permitam o monitoramento e controle da produção de fluidos nos poços. Para isso são desenvolvidos equipamentos específicos para medição de vazões. Este trabalho apresenta um sistema baseado em medidores de vazão por obstrução ou pressão diferencial (placas de orifício, bocais e Venturis) para determinação em linha de vazões de produção (óleo, gás e água) em poços de petróleo. A partir das equações de conservação da massa e do momento para escoamento unidimensional e considerando escoamento isotérmico com fases incompressíveis, sem mudança de fase, com fases líquidas homogeneizadas e com escorregamento constante entre as fases líquida e gasosa, é deduzida uma relação geral entre vazão mássica total e queda de pressão. Utilizando a correlação de Chisholm para o escorregamento, é realizada uma comparação entre os resultados obtidos com o modelo homogêneo e o modelo de escorregamento constante. Por meio de uma caracterização dos fluidos em produção em estado permanente e utilizando o modelo de black oil para o sistema óleo-gás, são determinadas as vazões de produção na condição de referência. São realizadas validações dos resultados do modelo com dados experimentais obtidos numa bancada experimental em Aracaju (Sergipe) e em poços de Urucu (Amazonas). A comparação com os resultados experimentais mostra que as predições feitas com o modelo de escorregamento podem ser consideradas satisfatórias, levando-se em conta que o modelo foi desenvolvido de maneira independente, sem parâmetros de ajuste dos dados experimentais. / The oil and gas industry has been working to develop methods to monitor and control the fluid production in the wells. For this purpose, specific equipments are developed for measuring stream flows. This work presents a system based on differential pressure (or obstruction) flow meters (orifice plates, Venturis and nozzles) for online determination of production flows (oil, gas and water) in oil wells. Starting from the mass and momentum conservation equations for one-dimensional, isothermal flow and considering incompressible phases without phase change, homogenized liquid phases and constant slip between gas and liquid phases, a general relationship between total mass flow and pressure drop is derived. Using Chisholmts correlation for the slip, a comparison is made between the results obtained with the homogeneous model and the constant slip model. Through a characterization of the production fluids in steady state and using the black oil model for the oil-gas system, the production flows are determined at the reference condition. A validation is made between results obtained with the model and experimental data obtained in a rig at Aracaju (Sergipe) and in wells at Urucu (Amazonas). The comparison with experimental results shows that the predictions made with the slip model may be considered satisfactory, taking into account that the model was developed independently, without parameters adjusted from the experimental data.
14

Sistema baseado em medidor de pressão diferencial para determinação em linha de vazões de produção em poços de petróleo. / System based on differential pressure device for in ine determination of production flow rate in oil wells.

Paz, Elson Francisco da 17 December 2010 (has links)
A indústria de petróleo e gás tem trabalhado para o desenvolvimento de métodos que permitam o monitoramento e controle da produção de fluidos nos poços. Para isso são desenvolvidos equipamentos específicos para medição de vazões. Este trabalho apresenta um sistema baseado em medidores de vazão por obstrução ou pressão diferencial (placas de orifício, bocais e Venturis) para determinação em linha de vazões de produção (óleo, gás e água) em poços de petróleo. A partir das equações de conservação da massa e do momento para escoamento unidimensional e considerando escoamento isotérmico com fases incompressíveis, sem mudança de fase, com fases líquidas homogeneizadas e com escorregamento constante entre as fases líquida e gasosa, é deduzida uma relação geral entre vazão mássica total e queda de pressão. Utilizando a correlação de Chisholm para o escorregamento, é realizada uma comparação entre os resultados obtidos com o modelo homogêneo e o modelo de escorregamento constante. Por meio de uma caracterização dos fluidos em produção em estado permanente e utilizando o modelo de black oil para o sistema óleo-gás, são determinadas as vazões de produção na condição de referência. São realizadas validações dos resultados do modelo com dados experimentais obtidos numa bancada experimental em Aracaju (Sergipe) e em poços de Urucu (Amazonas). A comparação com os resultados experimentais mostra que as predições feitas com o modelo de escorregamento podem ser consideradas satisfatórias, levando-se em conta que o modelo foi desenvolvido de maneira independente, sem parâmetros de ajuste dos dados experimentais. / The oil and gas industry has been working to develop methods to monitor and control the fluid production in the wells. For this purpose, specific equipments are developed for measuring stream flows. This work presents a system based on differential pressure (or obstruction) flow meters (orifice plates, Venturis and nozzles) for online determination of production flows (oil, gas and water) in oil wells. Starting from the mass and momentum conservation equations for one-dimensional, isothermal flow and considering incompressible phases without phase change, homogenized liquid phases and constant slip between gas and liquid phases, a general relationship between total mass flow and pressure drop is derived. Using Chisholmts correlation for the slip, a comparison is made between the results obtained with the homogeneous model and the constant slip model. Through a characterization of the production fluids in steady state and using the black oil model for the oil-gas system, the production flows are determined at the reference condition. A validation is made between results obtained with the model and experimental data obtained in a rig at Aracaju (Sergipe) and in wells at Urucu (Amazonas). The comparison with experimental results shows that the predictions made with the slip model may be considered satisfactory, taking into account that the model was developed independently, without parameters adjusted from the experimental data.
15

Giant Oil Fields - The Highway to Oil : Giant Oil Fields and their Importance for Future Oil Production

Robelius, Fredrik January 2007 (has links)
<p>Since the 1950s, oil has been the dominant source of energy in the world. The cheap supply of oil has been the engine for economic growth in the western world. Since future oil demand is expected to increase, the question to what extent future production will be available is important. </p><p>The belief in a soon peak production of oil is fueled by increasing oil prices. However, the reliability of the oil price as a single parameter can be questioned, as earlier times of high prices have occurred without having anything to do with a lack of oil. Instead, giant oil fields, the largest oil fields in the world, can be used as a parameter.</p><p>A giant oil field contains at least 500 million barrels of recoverable oil. Only 507, or 1 % of the total number of fields, are giants. Their contribution is striking: over 60 % of the 2005 production and about 65 % of the global ultimate recoverable reserve (URR). </p><p>However, giant fields are something of the past since a majority of the largest giant fields are over 50 years old and the discovery trend of less giant fields with smaller volumes is clear. A large number of the largest giant fields are found in the countries surrounding the Persian Gulf. </p><p>The domination of giant fields in global oil production confirms a concept where they govern future production. A model, based on past annual production and URR, has been developed to forecast future production from giant fields. The results, in combination with forecasts on new field developments, heavy oil and oil sand, are used to predict future oil production.</p><p>In all scenarios, peak oil occurs at about the same time as the giant fields peak. The worst-case scenario sees a peak in 2008 and the best-case scenario, following a 1.4 % demand growth, peaks in 2018.</p>
16

Giant Oil Fields - The Highway to Oil : Giant Oil Fields and their Importance for Future Oil Production

Robelius, Fredrik January 2007 (has links)
Since the 1950s, oil has been the dominant source of energy in the world. The cheap supply of oil has been the engine for economic growth in the western world. Since future oil demand is expected to increase, the question to what extent future production will be available is important. The belief in a soon peak production of oil is fueled by increasing oil prices. However, the reliability of the oil price as a single parameter can be questioned, as earlier times of high prices have occurred without having anything to do with a lack of oil. Instead, giant oil fields, the largest oil fields in the world, can be used as a parameter. A giant oil field contains at least 500 million barrels of recoverable oil. Only 507, or 1 % of the total number of fields, are giants. Their contribution is striking: over 60 % of the 2005 production and about 65 % of the global ultimate recoverable reserve (URR). However, giant fields are something of the past since a majority of the largest giant fields are over 50 years old and the discovery trend of less giant fields with smaller volumes is clear. A large number of the largest giant fields are found in the countries surrounding the Persian Gulf. The domination of giant fields in global oil production confirms a concept where they govern future production. A model, based on past annual production and URR, has been developed to forecast future production from giant fields. The results, in combination with forecasts on new field developments, heavy oil and oil sand, are used to predict future oil production. In all scenarios, peak oil occurs at about the same time as the giant fields peak. The worst-case scenario sees a peak in 2008 and the best-case scenario, following a 1.4 % demand growth, peaks in 2018.
17

The 19th Century Olive Oil Industry In Ayvalik And Its Impact On The Settlement Pattern

Terzi, Esra 01 December 2007 (has links) (PDF)
Ayvalik which is located on the Aegean coast of the West Anatolia made its main breakthrough in the 19th century and owe this development to olive oil production which was the main economic input of the settlement since the establishment of Ayvalik. Ayvalik was within the hinterland of izmir which was gained importance as a regional trade centre in the 19th century. Thus, Ayvalik found the way to improve its trade relations in an international level and eventually increase its olive oil production volume due to the growing demands. The new form of olive oil production / factories, developed together with the traditional house and workshop productions in the last quarter of the 19th century in Ayvalik. These three forms of production made up the second significant usage within the Ayvalik after the residential areas. The two or more floored, large volumed buildings were especially located on the shore, near to the port and trade facilities, on a flat terrain and became the most dominant and attractive buildings of the settlement. Besides the impressive industrial buildings, olive oil production itself effected the settlement pattern of Ayvalik. The main transportation axes were formed accordingly to the relationship between raw material areas and production places. The olive oil production also has an effect on the physical development direction of the settlement. The areas influenced from the negative effects of the production i.e., smell and dust were not chosen for development. The development of industrial buildings also blocked the physical relationship between the residential areas and sea. The industrial buildings such as factories, workshops and warehouses along the coast line reflect the industrial character of Ayvalik in the settlement&rsquo / s silhouette.
18

Environmental Effectiveness Analysis Of Caspian Hydrocarbon Development

Atay, Deniz 01 September 2009 (has links) (PDF)
Caspian region&#039 / s hydrocarbon deposits constitute one of the significant reserves in the world. This has caused a competition among state and non-state actors in exploiting these resources since 19th century. After the Soviet demise, the newly independent states embraced the economic gains made possible with the existence of these reserves. However oil production may have negative implications on environment, ecological balance and biodiversity if carried out in an uncontrolled manner. This study aims to identify these negative impacts and measures taken to control this process. Measures taken on national, regional and international levels are analyzed to find out the extent of their effectiveness in protecting the environment during oil operations. National legal frameworks of each littoral state, impacts of civil society organizations, regional and international legal frameworks and efforts of international organizations are evaluated. Since most of these improvements are relatively new with no viable outcome at hand, the process rather than the results is focused on. The application of time, holism and action-orientation parameters to these improvements to find out the environmental effectiveness of each shows that there is a preliminary burgeoning awareness in matters of environmental protection yielding to more effective efforts than before. Yet the economic gains remain too significant a temptation for the states in the region to be sacrificed. In the cases where measures taken to protect the environment undermine these economic gains, environmental effectiveness is forsaken.
19

Extra Korolev Producers: Their Impact On Production

Yskak, Aidos 01 September 2010 (has links) (PDF)
In this study, a three-dimensional, three-phase dynamic simulation model based on geological investigations of Korolev oilfield in Kazakhstan was used as a development planning tool in order to improve performance of three new wells. The model, developed previously by means of a seismic study, well log and core data, incorporating with characteristics of oilfield productivity, properties of reservoir, liquids and gases that are saturating the hydrocarbon-bearing horizon can be used to calculate development parameters for Korolev field, including production well locations, drilling schedules, and to facilitate both long-term and short-term forecasting for the purposes of optimizing the hydrocarbon recovery from the field. The objective of this work is to assess the impact of adding 3 extra producing wells and find ways to optimize cumulative production with the least impact on the existing development plan by means of deeper understanding subsurface dynamic processes of the Korolev field. The challenge is a high degree of connectivity between wells in the productive formation throughout the field so that any change of production parameters affects the whole field&rsquo / s cumulative production. Trying to find a solution to optimum production of the reservoir forecast studies were carried out, the impact of each new well on development parameters was defined, sub-surface processes changes due to extra producers lead-in were explained and as a result of this thesis two optimization models were proposed, one of which will bring nearly 9.7 million barrels more oil.
20

[en] OIL UPSTREAM PROJECT EVALUATION WITH REAL OPTIONS: APPROACH BY LEAST SQUARES MONTE CARLOS / [pt] AVALIAÇÃO DE PROJETOS DE EXPLORAÇÃO E PRODUÇÃO DE PETRÓLEO VIA OPÇÕES REAIS: ABORDAGEM POR MÍNIMOS QUADRADOS DE MONTE CARLO

MARCIO AUGUSTO LEONE KOENIGSDORF 03 March 2010 (has links)
[pt] No mundo competitivo e globalizado, dadas as inúmeras possibilidades de alocação de capital e as incertezas econômicas intrínsecas às decisões de investimento, a seleção de projetos lucrativos é um elemento de fundamental importância para o sucesso das empresas. Os métodos tradicionais de avaliação de investimentos, como o fluxo de caixa descontado (FCD), vêm sendo muito criticados por não capturarem de maneira adequada as flexibilidades existentes nos projetos. As vantagens de incluir a flexibilidade gerencial e a utilização mais freqüente da teoria de opções reais na avaliação de projetos permitem ampliar as discussões teóricas dos métodos utilizados para tal avaliação. A presente dissertação tem por finalidade a aplicação do Método dos Mínimos Quadrados de Monte Carlo (LSM) na avaliação econômica de projetos de Exploração e Produção de Petróleo (E&P). Para o cálculo das opções reais com o LSM foi construído um programa em VBA (Visual Basic for Applications) que, além de calcular o valor das opções, permite executar análises de sensibilidade. Para a validação do método, utilizou-se a aproximação analítica de Bjerksund & Stensland, por ser uma das mais utilizadas na avaliação de opções reais e por produzir a curva de exercício ótimo dessas opções. Na busca dos parâmetros a serem utilizados neste estudo, simulou-se um fluxo de caixa de um projeto de E&P. Por fim, os resultados obtidos não podem ser considerados definitivos, apenas poderão balizar o desenvolvimento e o aprimoramento da utilização do método LSM em Opções Reais. / [en] In a globalized and competitive world, given the many possibilities of capital allocation and inherent economic uncertainties in investment decisions, the selection of profitable projects is an element of fundamental importance for companies’ success. The traditional methods for investments valuation, such as discounted cash flow (DCF), have been being criticized for not capturing adequately projects flexibilities. The advantages of including management flexibility and more frequent use of the real options theory in the evaluation of projects allow us to expand the theoretical discussions of the methods used for valuation. This study aims to apply the least squares Monte Carlo (LSM) method in economic valuation of upstream oil projects. For calculating real options with the LSM, a program in VBA (Visual Basic for Applications) language was built. Besides calculating the options value, it lets you run a sensitivity analysis. To validate the method, the analytical solution of Bjerksund & Stensland was used, as it is one of the most used in real options valuation and produces a graph of the optimal exercise for those options. In search for parameters to be used, a cash flow for an upstream oil project was simulated. Finally, the results can not be considered definitive; they can only guide the development and improvement of the use of LSM in Real Options.

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