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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.
541

Estudo da adsor??o do c?lcio e estr?ncio da ?gua produzida utilizando carv?o baba?u / A study on adsorption of calcium and strontium from produced water by using babassu charcoal

Medeiros, Hena Lissa de Sousa 30 June 2015 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-05-10T22:49:41Z No. of bitstreams: 1 HenaLissaDeSousaMedeiros_DISSERT.pdf: 2450139 bytes, checksum: 33f229e4eaf5df1a317d891b6b53240c (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-05-17T22:45:27Z (GMT) No. of bitstreams: 1 HenaLissaDeSousaMedeiros_DISSERT.pdf: 2450139 bytes, checksum: 33f229e4eaf5df1a317d891b6b53240c (MD5) / Made available in DSpace on 2016-05-17T22:45:27Z (GMT). No. of bitstreams: 1 HenaLissaDeSousaMedeiros_DISSERT.pdf: 2450139 bytes, checksum: 33f229e4eaf5df1a317d891b6b53240c (MD5) Previous issue date: 2015-06-30 / Ag?ncia Nacional do Petr?leo - ANP / A ?gua produzida ? um dos principais res?duos gerados durante a explora??o e produ??o de petr?leo, devido ao grande volume e a sua composi??o qu?mica complexa surge ? preocupa??o para que as concentra??es dos contaminantes atendam as legisla??es vigentes, com a finalidade de reduzir os efeitos nocivos ao meio ambiente provocado pelo seu descarte sem tratamento pr?vio. Assim, o objetivo deste trabalho ? caracterizar a ?gua produzida no Campo de Periquito, do Estado do RN e avaliar o potencial adsortivo do carv?o vegetal de coco baba?u para remo??o dos metais Ca e Sr da ?gua produzida, visando a sua adequa??o para descarte. Atrav?s da caracteriza??o f?sico-qu?mica da ?gua produzida, p?de-se observar que as concentra??es dos metais c?lcio e estr?ncio foram: 322 mg/L e 69 mg/L, respectivamente. O material a ser utilizado como adsorvente foi caracterizado por diferentes t?cnicas f?sico-qu?micas, tais como: granulometria, densidade aparente, an?lise elementar, an?lise t?rmica, FRX, MEV, DRX e pHPZC. De posse das an?lises das caracteriza??es foram realizados ensaios de adsor??o, pelo m?todo de banho finito em solu??es sint?ticas dos metais Ca e Sr. Os resultados demonstraram que o carv?o baba?u possui remo??o m?xima em baixas concentra??es. Paralelamente ao estudo de adsor??o em solu??es sint?ticas, foi realizado ensaios de adsor??o com a ?gua produzida e o resultado mostrou que o carv?o baba?u possui bom potencial de adsor??o, removendo acima de 50 % do c?lcio e acima 45 % do estr?ncio, e apresentando valores para a capacidade de adsor??o de 17,31 mg/g para o c?lcio e 3,15 mg/g para o estr?ncio. Para otimizar os ensaios de adsor??o foi aplicado o planejamento fatorial completo de dois n?veis com o intuito de verificar a influ?ncia da concentra??o dos metais Ca e Sr e a massa do adsorvente em solu??o sint?tica sobre a % remo??o e a capacidade de adsor??o dos metais. Atrav?s dos resultados das an?lises das superf?cies de respostas p?de-se observar que as regi?es ?timas para a remo??o dos metais foram no n?vel superior da concentra??o dos metais e no n?vel superior da massa de adsorvente (+1,+1) obtendo uma remo??o m?xima de 58 % do c?lcio e 63 % do estr?ncio. / Produced water is a major waste generated during oil exploration and production. Due to its large volume and complex chemical composition an effort arises so that the contaminant concentrations meet the current legislation, in order to reduce harmful effects on the environment caused by its disposal without prior treatment. The objective of this paper is to characterize produced water from the Periquito field, RN, Brazil, and assess the adsorptive potential of babassu nut charcoal for removal of calcium and strontium from produced water, focusing on its suitability for disposal. Through the physicochemical characterization of the produced water, it was possible to observe that the concentrations of calcium and strontium were: 322 mg/L and 69 mg/L, respectively. The material to be used as an adsorbent was characterized through different physicochemical techniques, such as laser particle size, density, elemental analysis, thermal analysis, XRF, SEM, XRD and pHPZC. Provided the characterization analysis, adsorption experiments were carried out using the method of finite bath in synthetic solutions of both calcium and strontium. The results showed that babassu nut charcoal has maximum adsorption removal at low concentrations. In parallel with the study on adsorption in synthetic solutions, adsorption experiments were performed with produced water, whose results showed that babassu nut charcoal has good adsorption potential, removing over 50% of calcium and above 45% strontium, and having values of 17.31 mg/g for the adsorption capacity for calcium and 3.15 mg/g for strontium. In order to optimize the experiments, the full factorial design of two levels was applied in order to verify the influence of the concentration of calcium, strontium and the mass of the adsorbent in synthetic solution on the percentage of removal (%) and the adsorption capacity of adsorption of these metals. From the analysis results, it was possible to observe that the optimal regions for the removal of these metals was in the upper level of the metal concentration and in the upper level of the adsorbent mass (+1, +1) obtaining a maximum removal of 58 % for calcium and 63 % for strontium.
542

An?lise comparativa de diferentes configura??es de po?os no processo de combust?o in-situ

Rocha, Mirella Lopes da 22 February 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-07-11T17:35:18Z No. of bitstreams: 1 MirellaLopesDaRocha_DISSERT.pdf: 4193744 bytes, checksum: f2fd7a25cfa4b47013fb029c75d748a3 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-07-18T17:12:19Z (GMT) No. of bitstreams: 1 MirellaLopesDaRocha_DISSERT.pdf: 4193744 bytes, checksum: f2fd7a25cfa4b47013fb029c75d748a3 (MD5) / Made available in DSpace on 2016-07-18T17:12:19Z (GMT). No. of bitstreams: 1 MirellaLopesDaRocha_DISSERT.pdf: 4193744 bytes, checksum: f2fd7a25cfa4b47013fb029c75d748a3 (MD5) Previous issue date: 2016-02-22 / Com um n?mero crescente de campos maduros, a recupera??o de ?leo pesado tem se apresentado um dos grandes desafios do setor petrol?fero. O Nordeste Brasileiro, por exemplo, possui in?meros reservat?rio de ?leo pesado que possam vir a ser explorados com a utiliza??o de m?todos t?rmicos. Dentre os tipos de m?todos utilizados para ?leos pesados, destaca-se o m?todo da combust?o in-situ, uma t?cnica no qual o calor ? produzido dentro do reservat?rio, diferente da inje??o de fluido aquecido em que o calor ? gerado na superf?cie e transportado para o reservat?rio. Neste tipo de processo, ? comum utilizar po?os verticais como injetores e produtores. Contudo, m?todos que utilizam po?os horizontais como produtores de ?leo s?o cada vez mais estudados devido ? maior ?rea de contato entre a forma??o e a frente de combust?o. Sendo assim, o objetivo principal do presente trabalho foi estudar as diferentes configura??es de po?os (CIS, THAITM e CAGD) no processo de combust?o in-situ, na recupera??o de ?leo, utilizando um reservat?rio semissint?tico com caracter?sticas do Nordeste Brasileiro. O m?todo ?toe-to-heel air injection? (THAITM) ? um processo de recupera??o de petr?leo avan?ado, que consiste na integra??o da combust?o in-situ com os avan?os tecnol?gicos na perfura??o de po?os horizontais. Este m?todo utiliza po?os horizontais como produtores de ?leo, mantendo po?os injetores verticais para a inje??o de ar. O processo de drenagem de ?leo por diferencial gravitacional assistida com combust?o (CAGD) ? um sistema integrado, nesta configura??o o po?o injetor horizontal ? perfurado na parte superior de forma??o,com um po?o horizontal produtor na se??o inferior. As simula??es foram realizadas em um programa comercial de processos t?rmicos, denominado ?STARS? (Steam, Thermal, and Advanced Processes Reservoir Simulator), da empresa CMG (Computer Modelling Group). Foi realizada uma an?lise da vaz?o de inje??o de ar e verificou-se que cada m?todo possu?a um limite m?ximo de inje??o para o modelo base, mostrando que passando desse limite de inje??o de ar, havia redu??o da produ??o acumulada de ?leo. Foram realizadas an?lises dos par?metros operacionais: vaz?es de inje??o, configura??o e completa??o dos po?os. Na an?lise de sensibilidade foi encontrado que a vaz?o de inje??o de ar apresentou maior influ?ncia no m?todo THAI, j? no m?todo CIS a completa??o dos po?os foi o par?metro mais influente e no CAGD a configura??o de po?os foi o que apresentou maior influ?ncia na fra??o recuperada. Os resultados econ?micos mostraram que o melhor caso obtido foi o m?todo CAGD,pois, apesar de possuir maior custo inicial, foi o que apresentou melhor retorno financeiro quando comparado com os melhores casos do CIS e THAI. / With an increasing number of mature fields, heavy oil recovery has performed one of the great challenges of the oil industry. The Brazilian Northeast, for example, has numerous heavy oil reservoirs are explored with the use of thermal methods. Among the types of methods used for heavy oil, there is the method of in-situ combustion, a technique in which heat is produced within the container, unlike the injection of heated fluid when the heat is generated at the surface and transported to the reservoir. In this type of process, it is common to use vertical wells as injectors and producers. However, methods which use horizontal wells like oil producers are increasingly studied because of greater contact area between the formation and combustion front. Thus, the main objective of this work was to study the different configurations of wells (CIS THAITM and CAGD) in the process of in-situ combustion in oil recovery using a semi-synthetic tank with Brazilian Northeast features. The method "toe-to-heel air injection" (THAITM) is a process of enhanced oil recovery, which is the integration of in-situ combustion with technological advances in drilling horizontal wells. This method uses horizontal wells such as oil producers, keeping vertical injection wells for injecting air. The oil drain process by differential gravitational assisted with combustion (CAGD) is an integrated, in this configuration the horizontal injector well is drilled at the top formation with a horizontal production well in the lower section. The simulations were performed in a commercial program of thermal processes, called "STARS" (Steam, Thermal, and Advanced Processes Reservoir Simulator), the company CMG (Computer Modelling Group). An analysis of the air flow injection was performed and it was found that each method had a maximum injection to the base model, a show that through this air injection limit was reduced cumulative production of oil. Analyses of operating parameters were used: injection flow, configuration and completion of wells. In the sensitivity analysis we found that the air injection flow showed greater influence on THAI method, since the CIS method the completion of the wells was the most influential parameter and CAGD configuration wells showed the greatest influence in the recovered fraction. The economic results have shown that the best case obtained in CAGD method because, despite having higher initial cost showed the best financial return compared to the best cases the CIS and THAI.
543

Estimador de estados para Plunger Lift

Dourado J?nior, Osmar de Ara?jo 19 June 2017 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2018-01-24T12:15:33Z No. of bitstreams: 1 OsmarDeAraujoDouradoJunior_TESE.pdf: 3621125 bytes, checksum: ac4c7dbcd5830c2fa16d1e8be1ae3ee1 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2018-01-26T14:00:19Z (GMT) No. of bitstreams: 1 OsmarDeAraujoDouradoJunior_TESE.pdf: 3621125 bytes, checksum: ac4c7dbcd5830c2fa16d1e8be1ae3ee1 (MD5) / Made available in DSpace on 2018-01-26T14:00:19Z (GMT). No. of bitstreams: 1 OsmarDeAraujoDouradoJunior_TESE.pdf: 3621125 bytes, checksum: ac4c7dbcd5830c2fa16d1e8be1ae3ee1 (MD5) Previous issue date: 2017-06-19 / O objetivo desta Tese ? apresentar um Estimador de Estado para po?os de Plunger Lift com base no algoritmo Extended Kalman Filter (EKF). O estimador de estado ? uma opera??o conjunta da aplica??o para o modelo din?mico de Plunger Lift (PL) na abordagem de Espa?o de Estados e algoritmo EKF. O modelo ? constitu?do por um conjunto de equa??es diferenciais e alg?bricas (DAEs) discretas e modeladas na forma de equa??es no espa?o de estados, levando em conta os sinais de medi??o na presen?a de ru?do. O algoritmo EKF ? aplicado ao modelo de espa?o de estado, resultando num estimador de estado capaz de processar o sinal de medi??o, proporcionando assim estimativas das vari?veis de estado, que neste problema s?o a velocidade da golfada e a press?o no topo do revestimento. A simula??o computacional realizada com dados de um po?o real ? apresentada e os resultados mostraram que o estimador de estados proposto ? capaz de fornecer predi??es para po?os de petr?leo operados por PL. / The aim of this Thesis is to present a State Estimator for Plunger Lift wells based on the Extended Kalman Filter (EKF) algorithm. The state estimator is a joint operation of the application for the Plunger Lift (PL) dynamic model in State Space approach and EKF algorithm. The model is constituted by a set of discrete differential algebraic equations (DAEs) discretized and modeled in the form of equations in state space taking into account the measurement signals in the presence of noise. EKF algorithm is applied to the state space model, resulting in a state estimator able to process the measurement signal thus providing estimates of the state variables, that in this problem are slug velocity and casinghead pressure. The computational simulation performed with data from a real well is presented and the results showed that the state estimator proposed is able to provide predictions for oil wells operated by PL.
544

Estudo do processo de drenagem gravitacional assistido por vapor utilizando po?os injetores verticais e horizontais na recupera??o de ?leos pesados

Rocha, Marcel Ara?jo 14 March 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-01-13T12:25:48Z No. of bitstreams: 1 MarcelAraujoRocha_DISSERT.pdf: 5011334 bytes, checksum: d4996c7516aeda7455db92bc1ebfc1d5 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-01-23T13:23:05Z (GMT) No. of bitstreams: 1 MarcelAraujoRocha_DISSERT.pdf: 5011334 bytes, checksum: d4996c7516aeda7455db92bc1ebfc1d5 (MD5) / Made available in DSpace on 2017-01-23T13:23:05Z (GMT). No. of bitstreams: 1 MarcelAraujoRocha_DISSERT.pdf: 5011334 bytes, checksum: d4996c7516aeda7455db92bc1ebfc1d5 (MD5) Previous issue date: 2016-03-14 / A explora??o de reservas de hidrocarbonetos pesados e extrapesados ? de interesse primordial para muitas companhias de petr?leo, uma vez que, a magnitude desses recursos representa parte da energia mundial. A produ??o de ?leo pesado, a partir de dep?sitos subterr?neos, ? complexa, at? mesmo sob as melhores circunst?ncias, devido principalmente ? elevada viscosidade do ?leo. Para melhor desenvolver o processo de produ??o, tornando-o eficiente, de maneira que os fluidos que n?o seriam produzidos consigam chegar ? superf?cie, foram desenvolvidos m?todos de recupera??o convencionais e especiais, para obten??o de um maior fator de recupera??o e, consequentemente, uma maior lucratividade na opera??o de explota??o dessas jazidas. Para reduzir a alta viscosidade e as elevadas tens?es interfaciais, foram desenvolvidos os m?todos t?rmicos. Nesse trabalho, simulou-se a inje??o continua de vapor, com po?os injetores verticais e horizontais, para desenvolver um reservat?rio com caracter?sticas do Nordeste brasileiro, de ?leo pesado, atrav?s da condu??o dos fluidos produzidos com po?o horizontal. Foram feitas an?lises t?cnicas e econ?micas dos modelos que diferiam quanto ?s suas restri??es e arranjos estruturais do sistema. Na configura??o horizontal se observou a influ?ncia da vaz?o de inje??o, da dist?ncia vertical e da dist?ncia lateral sobre o fator de recupera??o. Na configura??o vertical se analisou a influ?ncia da vaz?o de inje??o, da completa??o dos injetores, da dist?ncia lateral e da quantidade de po?os injetores sobre o fator de recupera??o. Diante dos modelos proposto, analisou-se a produ??o acumulada de ?leo, o Volume Poroso Injetado, a forma??o das c?maras de vapor e o Valor Presente L?quido. Tecnicamente, os modelos em que se injetou vapor com po?os verticais obtiveram maior fator de recupera??o de ?leo, j? os modelos horizontais se sobressa?ram economicamente. / The reserves exploration of heavy and extra heavy hydrocarbon is of prime interest to many oil companies, since the magnitude of these resources the magnitude of these resources still stands out on the global and Brazilian energy matrix. The production of heavy oil, from the underground deposits is complex, even on the best of circumstances, mainly due to the high viscosity of the oil. To further develop the process of production, making it efficient, so that the fluids that would not be produced get to reach the surface, complementary recovery methods and advanced were developed to obtain a higher recovery factor and, hence, greater profitability in operation exploitation of these deposits. To combat the high viscosity and high interfacial tensions, thermal methods were developed. In this work, the steam injection continues was simulated in vertical and horizontal injection wells, to develop a reservoir with characteristics of the Brazilian Northeast of heavy oil, by conducting fluid produced with horizontal well. Technical and economic analyzes were made of the models that differ in their structural constraints and system arrangements. In horizontal configuration was observed the influence of the injection flow, of the vertical distance and of the lateral distance over the recovery factor. In vertical configuration was analyzed the influence of the injection flow, of the injection wells completion, of the lateral distance and the amount of injection wells over the recovery factor. Faced the proposed models, was analyzed the cumulative oil production, the Pore Volume Injected, the formation of steam chambers and the Net Present Value. Technically, the models in which steam is injected with vertical wells had higher recovery factor of oil, since the horizontal models stood out economically.
545

Algoritmo ultra r?pido para calcular propriedades cr?ticas no problema de percola??o em redes bidimensionais

Ecco, Daniel 29 July 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-01-27T13:40:52Z No. of bitstreams: 1 DanielEcco_TESE.pdf: 15819405 bytes, checksum: 00c65d8e05776036ef4d17fa23f04e68 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-01-31T14:21:06Z (GMT) No. of bitstreams: 1 DanielEcco_TESE.pdf: 15819405 bytes, checksum: 00c65d8e05776036ef4d17fa23f04e68 (MD5) / Made available in DSpace on 2017-01-31T14:21:06Z (GMT). No. of bitstreams: 1 DanielEcco_TESE.pdf: 15819405 bytes, checksum: 00c65d8e05776036ef4d17fa23f04e68 (MD5) Previous issue date: 2016-07-29 / Atrav?s de estudos sobre percola??o, pode-se determinar se uma rede bidimensional percola, percorrendo apenas parte das fronteiras dos aglomerados, verificando se existem dois s?tios da fronteira conectados em lados opostos da rede, isto ?, sem a necessidade de preencher todos os s?tios que formam os aglomerados. O objeto desta tese ? um algoritmo para tal fim. Diante da velocidade que este algoritmo ter?, percorrendo apenas parte das fronteiras dos aglomerados, vimos que seria poss?vel estudar redes de tamanhos jamais alcan?ados (superiores a um trilh?o de s?tios), com complexidade menor que 1 e um baixo custo computacional em rela??o aos algoritmos j? desenvolvidos sobre o tema percola??o. Passamos, com isso, a querer estudar o comportamento do limiar de percola??o e da dimens?o fractal da fronteira em redes dos mais diversos tamanhos e com uma grande quantidade de simula??es, as quais os resultados permitiram fazer compara??es e confirmar as previs?es feitas atrav?s de leis de escalas j? conhecidas na literatura. / Through studies on percolation, can determine if a percolates dimensional network, covering only part of the borders of the agglomerates by checking if there are two border sites connected on opposite sides of the net, i.e. without the need to fill all the sites form agglomerates. The object of this thesis is an algorithm for this purpose. Given the speed that this algorithm will, covering only part of the borders of the clusters, we saw that it would be possible to study never reached sizes of networks (more than one trillion websites), with less complexity than 1 and a low computational cost compared to the algorithms already developed on the theme percolation. We pass, therefore, to want to study the behavior of percolation threshold and the fractal dimension of the border into networks of different sizes and with a lot of simulations, which results allowed comparisons and confirm the predictions made by laws scales known in the literature.
546

Estudo da configura??o de po?os no processo de drenagem gravitacional assistida por vapor (SAGD) em reservat?rios do nordeste brasileiro

Fernandes, Glydianne Mara Di?genes 02 September 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-02-10T16:44:40Z No. of bitstreams: 1 GlydianneMaraDiogenesFernandes_TESE.pdf: 3862064 bytes, checksum: fefa5eff9a9888901a0fc8b23ab2f361 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-02-10T21:36:27Z (GMT) No. of bitstreams: 1 GlydianneMaraDiogenesFernandes_TESE.pdf: 3862064 bytes, checksum: fefa5eff9a9888901a0fc8b23ab2f361 (MD5) / Made available in DSpace on 2017-02-10T21:36:27Z (GMT). No. of bitstreams: 1 GlydianneMaraDiogenesFernandes_TESE.pdf: 3862064 bytes, checksum: fefa5eff9a9888901a0fc8b23ab2f361 (MD5) Previous issue date: 2016-09-02 / As novas tecnologias que utilizam a recupera??o avan?ada de petr?leo surgiram da necessidade de se retirar o ?leo que ainda permanece no reservat?rio ap?s a recupera??o prim?ria. O objetivo desses m?todos ? elevar o fator de recupera??o do ?leo. Dessa forma, alguns projetos passam a se tornar vi?veis economicamente quando se utilizam esses m?todos. Os m?todos t?rmicos, dentre eles a inje??o de vapor, promovem a recupera??o do ?leo atrav?s da inser??o de energia t?rmica dentro do reservat?rio. O aumento da temperatura faz com que o ?leo tenha a sua viscosidade reduzida, aumentando assim, seu deslocamento em dire??o aos po?os de produ??o. O processo de drenagem gravitacional assistida por vapor (SAGD) ? um m?todo avan?ado de recupera??o. Sua configura??o apresenta dois po?os horizontais paralelos, um acima do outro. O vapor ? injetado de forma cont?nua ao longo do po?o injetor, em seguida forma-se uma c?mara de vapor que cresce at? encontrar os limites do reservat?rio. Este ?leo tem, ent?o, sua viscosidade reduzida e, pela a??o das for?as gravitacionais, ? drenado em dire??o ao po?o produtor. Neste contexto, esta pesquisa teve como objetivo realizar um estudo de diferentes configura??es de po?os injetores no processo SAGD, considerando os efeitos das perdas de carga e calor no po?o injetor em reservat?rios do nordeste brasileiro. Um planejamento fatorial foi utilizado para verificar a influ?ncia dos par?metros estudados no fator de recupera??o. Foi realizada tamb?m uma an?lise t?cnico econ?mica das configura??es dos po?os injetores com a finalidade de analisar a rentabilidade dos projetos estudados. Para a realiza??o das simula??es num?ricas foi utilizado o simulador t?rmico STARS da CMG (Computer Modelling Group). Os resultados mostraram que os po?os injetores inclinados apresentaram uma menor produ??o em rela??o ? configura??o com po?os horizontais. A configura??o com po?os injetores deslocados em rela??o ao po?o produtor (W-SAGD), para vaz?es de inje??o a partir de 100 ton/dia, levou a forma??o de uma c?mara de vapor maior e mais eficiente. Foi observado tamb?m que a utiliza??o de po?os injetores verticais (V-SAGD), para maiores vaz?es de inje??o de vapor, apresentou uma produ??o acumulada de ?leo menor, por?m, similar ao SAGD com po?o injetor horizontal. Na an?lise econ?mica, o modelo SAGD apresentou os maiores VPLs. / New technologies that use the enhanced oil recovery emerged the need to remove the oil that remains in the reservoir after primary recovery. The goal of these methods is to increase the oil recovery factor. Thus, some projects start to become economically viable when using these methods. The thermal methods, including steam injection, promote the recovery of oil through the thermal energy within the insert reservoir. The increased temperature causes the oil to have its viscosity reduced, thereby increasing its speed towards the production wells. The steam assisted gravity drainage process (SAGD) is an advanced method of recovery. Its configuration has two parallel horizontal wells, one above the other. The steam is injected continuously during the injection well, and then forms a steam chamber which grows to find the limits of the reservoir. This oil is then reduced its viscosity and, by the action of gravitational forces, it is drained toward the producing well. In this context, this study aimed to carry out a study of different configurations of injection wells in SAGD process, considering the effects of load loss and heat in the injection well in the Brazilian northeast reservoirs. A factorial design was used to investigate the influence of the parameters studied in the recovery factor. It also performed an economic analysis of the technical settings of injection wells in order to analyze the profitability of the projects studied. To perform the numerical simulations we used the thermal simulator CMG STARS (Computer Modelling Group). The results showed that the inclined injection wells had a lower production compared to the configuration with horizontal wells. A setting producer injectors offset from the well (W-SAGD) for injection flowrates from 100 ton/day, led to the formation of a vapor chamber larger and more efficient. It was also observed that the use of vertical injection wells (VSAGD), for larger flowrates, showed a lower cumulative production of oil, however, similar to SAGD injector well horizontally. In the economic analysis, the SAGD model showed the highest NPVs.
547

Novas nanoemuls?es aplicadas ? recupera??o avan?ada de petr?leo em reservat?rios carbon?ticos / New nanoemulsions applied to enhanced oil recovery in carbonate rocks

Meneses, Zildiany Ibiapina 23 May 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-02-10T16:44:41Z No. of bitstreams: 1 ZildianyIbiapinaMeneses_TESE.pdf: 5538896 bytes, checksum: aeb6e8b7a1071f0fe7d56cd5089c7e65 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-02-10T21:58:03Z (GMT) No. of bitstreams: 1 ZildianyIbiapinaMeneses_TESE.pdf: 5538896 bytes, checksum: aeb6e8b7a1071f0fe7d56cd5089c7e65 (MD5) / Made available in DSpace on 2017-02-10T21:58:03Z (GMT). No. of bitstreams: 1 ZildianyIbiapinaMeneses_TESE.pdf: 5538896 bytes, checksum: aeb6e8b7a1071f0fe7d56cd5089c7e65 (MD5) Previous issue date: 2016-05-23 / As nanoemuls?es s?o sistemas geralmente compostos por tensoativos, fase aquosa e fase oleosa. Podem variar de acordo com a composi??o, tamanho das got?culas dispersas, aspecto, aplica??es, dentre outros. Apresentam got?culas dispersas em escala nanom?trica, estabilidade cin?tica e aspecto transparente a transl?cido. Dentre suas vantagens, destaca-se a maior superf?cie de contato devido ao tamanho das got?culas dispersas, associado ? menor quantidade de mat?ria ativa. Este trabalho prop?e produzir novas nanoemuls?es atrav?s da dilui??o de microemuls?o com sua fase aquosa ou com fase aquosa polim?rica salina, e aplica??o na recupera??o de petr?leo em rochas carbon?ticas. A microemuls?o precursora ? composta por tensoativos ani?nico e n?o i?nico (UNT-L90 e sab?o base), cotensoativo (n-butanol), fase oleosa (querosene) e fase aquosa (solu??o de NaCl a 3,50%). Os sistemas nanoemulsionados foram estudados em rela??o ao percentual de tensoativos (1,00%, 1,25%, 2,00%, 2,50%, 5,00% e 7,00%) e ? presen?a de pol?meros (ani?nico e cati?nico, a 0,08%). Os sistemas propostos neste estudo foram caracterizados usando as seguintes t?cnicas: tamanho de got?cula, turbidez, tens?o superficial, tens?o interfacial, condutividade el?trica, pH, ?ndice de refra??o, densidade, reologia e SAXS. A microemuls?o e as nanoemuls?es, sem pol?mero, foram caracterizadas como fluidos Newtonianos, enquanto as nanoemuls?es polim?ricas como fluidos pseudopl?sticos. A microemuls?o foi termodinamicamente est?vel, transparente e com got?culas monodispersas, com 11,8 nm de di?metro. Os sistemas nanoemulsionados foram metaest?veis, com got?culas variando de 16,80 nm a 61,40 nm. Os sistemas microemulsionado e nanoemulsionados apresentaram micelas diretas do tipo ?miolo-casca? em seu interior. A microemuls?o e algumas nanoemuls?es estudadas foram utilizadas na recupera??o avan?ada de petr?leo, aplicadas a um reservat?rio carbon?tico contendo ?leo leve. Os melhores resultados foram de 99,56% e 75,18% de extra??o do ?leo remanescente, para a microemuls?o e nanoemuls?o, respectivamente; com recupera??es totais de ?leo original de 99,73% e 83,28%. O efeito sin?rgico entre o meio salino, micelas e pol?mero favoreceu a recupera??o de ?leo com as nanoemuls?es; cujo melhor resultado foi obtido com a NanoD2, composta por 2,50% de tensoativos, 3,50% de NaCl e 0,08% do pol?mero AN 934 PWG; embora as propriedades da rocha tamb?m tenham influ?ncia. O trabalho mostrou que nanoemuls?es e microemuls?es podem ser alternativas vi?veis para aplica??o em recupera??o avan?ada de petr?leo. / Nanoemulsions are systems generally composed by surfactant, aqueous phase and oil phase. These systems may vary according to their composition, size of dispersed droplets, appearance, applications, among others. They have nano-scale dispersed droplets, kinetic stability and an appearance from transparent to translucent. Among their advantages, it may be highlighted the large contact surface, due to the size of the dispersed droplets, associated with smaller amount of active matter. This research proposes the production of new nanoemulsions, through the dilution of microemulsion, with its aqueous phase or with saline polymeric aqueous phase, and their use to recover oil in carbonate rocks. The precursor microemulsion is composed of nonionic and anionic surfactants (UNT-L90 and soap base), cosurfactant (n-butanol), oil phase (kerosene) and aqueous phase (NaCl solution at 3.50%). The nanoemulsionated systems were studied based on the percentage of surfactants (1.00%, 1.25%, 2.00%, 2.50%, 5.00% and 7.00%) and on the presence of polymers (anionic and cationic, at 0.08%). The proposed systems were characterized by using the following techniques: droplet size, turbidity, surface tension, interfacial tension, electrical conductivity, pH, refractive index, density, rheology, and SAXS. The microemulsion and the nanoemulsions, without polymers, were characterized as Newtonian fluids, while the polymeric nanoemulsions were characterized as pseudoplastic fluids. The microemulsion was thermodynamically stable, transparent and had monodispersed droplets with a diameter of 11.80 nm. The nanoemulsionated systems were metastable, with droplets ranging from 16.80 nm to 61.40 nm. The microemulsionated and nanoemulsionated systems presented direct micelles, with a core-shell inner type. The microemulsion and some studied nanoemulsions were applied as an enhanced oil recovery method, through carbonate rocks containing light oil. The best results extracted 99.56% and 75.18% of the remaining oil, for the microemulsion and nanoemulsion, respectively, with total oil recovery of 99.73% and 83.28%. The synergic effect among saline medium, micelles and polymer favored the oil recovery with nanoemulsions; whose best result was obtained by NanoD2, composed of 2.50% surfactants, 3.50% NaCl and 0.08% of the AN 934 PWG polymer; although the rock properties also influences the process. The work showed that nanoemulsions and microemulsions can be viable alternatives for application in enhanced oil recovery.
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Identifica??o de um sistema multitanques utilizando redes de fun??es de base radial / Identification a multi tanks system using radial basis function networks

Silva, Brenna Karolyna dos Santos 23 February 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-02-21T00:17:08Z No. of bitstreams: 1 BrennaKarolynaDosSantosSilva_DISSERT.pdf: 6981280 bytes, checksum: 0266d5d98ab38bb268fe5ddd9e7e3c97 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-03-03T22:08:40Z (GMT) No. of bitstreams: 1 BrennaKarolynaDosSantosSilva_DISSERT.pdf: 6981280 bytes, checksum: 0266d5d98ab38bb268fe5ddd9e7e3c97 (MD5) / Made available in DSpace on 2017-03-03T22:08:40Z (GMT). No. of bitstreams: 1 BrennaKarolynaDosSantosSilva_DISSERT.pdf: 6981280 bytes, checksum: 0266d5d98ab38bb268fe5ddd9e7e3c97 (MD5) Previous issue date: 2016-02-23 / A identifica??o de sistemas din?micos n?o lineares tem grande import?ncia em v?rias ?reas da Engenharia. Esta disserta??o apresenta uma t?cnica de identifica??o de sistemas utilizando Redes Neurais Artificiais do tipo Fun??es de Base Radial ? RBF aplicada a um sistema bastante comum na ind?stria de qu?mica e petroqu?mica, o sistema de multitanques (tanques acoplados), que apresenta uma din?mica de natureza n?o linear. Em tal sistema, o comportamento n?o linear deste pode dificultar a identifica??o e apresentar um modelo que n?o reflete seu comportamento real. Esse fator ? fonte de motiva??o para utilizarmos uma ferramenta matem?tica tal como a RBF na identifica??o dos aspectos n?o lineares do sistema. Essa rede apresenta potencialidades como habilidade de tratar sistemas complexos, aprendizado e generaliza??o. A identifica??o de sistemas utilizando RBF pode ser tratada como um problema de ajuste de curvas atrav?s da combina??o das fun??es de base. / The identification of nonlinear dynamical systems is of great importance in many areas of engineering. In this dissertation presents a system identification technique using Artificial Neural Networks Radial Basis Function type - RBF applied to a very common system in the chemical and petrochemical industry, multi tanks system (coupled tanks), which features a dynamic nature not linear. In such a system, the nonlinear behavior of this can make it difficult to identify and present a model that does not reflect their actual behavior. This factor is a source of motivation we use a mathematical tool such as RBF in the identification of nonlinear aspects of the system. This network has potential as ability to handle complex systems, learning and generalization. Identification systems using RBF can be treated as a curve fitting problem by combining the basic functions.
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Otimiza??o do cronograma da inje??o c?clica de vapor atrav?s de modelos anal?ticos em uma abordagem probabil?stica

Oliveira, Felipe da Silva Pereira Albuquerque 12 September 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-02-21T00:17:08Z No. of bitstreams: 1 FelipeDaSilvaPereiraAlbuquerqueOliveira_DISSERT.pdf: 6576373 bytes, checksum: b11e6d9b4401f339a1102a38b4351fa4 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-03-03T22:40:49Z (GMT) No. of bitstreams: 1 FelipeDaSilvaPereiraAlbuquerqueOliveira_DISSERT.pdf: 6576373 bytes, checksum: b11e6d9b4401f339a1102a38b4351fa4 (MD5) / Made available in DSpace on 2017-03-03T22:40:49Z (GMT). No. of bitstreams: 1 FelipeDaSilvaPereiraAlbuquerqueOliveira_DISSERT.pdf: 6576373 bytes, checksum: b11e6d9b4401f339a1102a38b4351fa4 (MD5) Previous issue date: 2016-09-12 / Em campos de ?leo pesado onde se utilize a inje??o c?clica de vapor, uma das tarefas mais recorrentes, demoradas e importantes ? a defini??o do cronograma de estimula??o com vapor para as centenas de po?os produtores. A capacidade de gera??o de vapor ? usualmente limitada e ainda mais reduzida pelas recorrentes manuten??es dos geradores. Esse agendamento at? poderia ser feito a partir de um modelo num?rico, mas al?m de exigir a disponibilidade de infraestrutura computacional, s? ? vi?vel caso o tempo n?o seja um fator cr?tico nessa defini??o. A indisponibilidade de tempo para rodar as simula??es necess?rias para a otimiza??o ? normalmente um empecilho, haja vista que a tarefa deve ser recorrentemente realizada conforme as premissas evoluem no tempo. Por isso, a op??o mais comum ? aproveitar a experi?ncia do engenheiro e do ge?logo de reservat?rios em uma an?lise subjetiva dos par?metros de reservat?rio e hist?rico de produ??o, muitas vezes levando em considera??o um estudo feito para um po?o representativo daquele campo ou de uma ?rea do campo. Esse m?todo tem se mostrado eficaz, embora consuma razo?vel quantidade de tempo para an?lise das op??es e conte com a intui??o do profissional encarregado da tarefa. Muitas s?o as refer?ncias acad?micas sobre modelos anal?ticos para representar o processo de inje??o c?clica de vapor e, de posse desses modelos, foram publicadas tentativas de us?-los para maximizar os resultados da estimula??o de determinado po?o. Entretanto, abordaram o problema restrito de uma estimula??o em particular, sem que o problema da defini??o de qual po?o estimular a cada momento de disponibilidade do recurso cr?tico, que ? a capacidade instalada de gera??o de vapor. Esta disserta??o prop?e, portanto, uma nova metodologia sobre como combinar a simplicidade dos diversos modelos anal?ticos dispon?veis na literatura com a grande capacidade computacional moderna para realizar uma an?lise probabil?stica do melhor retorno econ?mico para a capacidade instalada de gera??o de vapor, podendo servir de base, inclusive, na an?lise de viabilidade econ?mica para aquisi??o de maior capacidade ou para mobilizar geradores entre campos ou entre ?reas de um mesmo campo. S?o tratados os aspectos te?ricos dos modelos anal?ticos incluindo as limita??es inerentes a alguns deles bem como em quais circunst?ncias a aplica??o teria mais confiabilidade al?m de poss?veis adapta??es que mitigariam algumas das preocupa??es sobre a aplicabilidade desses modelos. Ao inv?s de definir uma combina??o de modelo e estrat?gia que seja conveniente para todos os cen?rios de utiliza??o poss?vel, trata-se de uma sugest?o de metodologia a fim de alcan?ar melhores resultados, cabendo a quem for us?-la definir quais s?o as particularidades do caso concreto e buscar modelos e estrat?gias que convierem. Por fim, ganhos potenciais ficam claros com a compara??o dos resultados obtidos pelo m?todo com a op??o subjetiva mais intuitiva de injetar nos po?os seguindo uma ordem trivial com cotas fixas para um caso te?rico padr?o atrav?s da simula??o num?rica, para qual ser? utilizado o simulador STARS? da CMG para simula??o t?rmica. / Heavy oil fields that produce through cyclic steam stimulation often demands one very recurrent, time consuming and important task during its lifetime: stimulation scheduling along the hundreds of the existing wells. Installed steam generation capacity is usually lower than the demand and is diminished even more by maintenance stoppages. This scheduling could be defined using numerical simulation, but beyond demanding a computational infrastructure, the time needed to complete the task is usually much greater than the time available. Computational infrastructure is not usually an issue but time availability in order to run the numerous simulations necessary to complete the optimization task, as it is commonly recurrent as circumstances change as time passes. Therefore, the most common option has been to make use of the skills and experience the reservoir engineer and geoscientists gathered during their careers. Using historical production data and reservoir parameters in a subjective analysis, taking into account local experiences extrapolated to the adjacent area or even to the whole field, the reservoir team defines which order the stimulation should be done. That method has shown to be effective, but it takes time to be done and depends on the professional intuition. Many academic references describe analytical models that tries to represent the cyclic steam stimulation and using those models, some attempts were made in order to maximize the results of the stimulation of each well, regardless the of the critical resource usage optimization. This research proposes an unseen methodology versing about how to combine the simplicity of the numerous analytical models available and the amazing modern computational power in order to complete a probabilistic analysis of the optimum financial return that could be reached with the installed steam generation facilities. It can also be used to sustain decisions regarding either investing in capacity enlargement or transfer between fields or production areas. Analytical models theoretical aspects are discussed, including application limitations and in which circumstances one can have better confidence using them as well as which adaptations can be done to diminish lacks of fitting. Instead of defining a model and strategy combination that would fit every scenario, it is more likely a suggestion of a methodology that aims better results. Therefore, it is up to the evaluator to recognize which the characteristics of the real case are and choose a model and a strategy that better complies with the case. Finally, potential gains become clear as results from the methodology are compared with those obtained from an intuitive approach for a standard case through numerical simulation using Computer Modelling Group?s thermal simulator STARS?.
550

An?lise estat?stica do m?todo compressive sensing aplicado a dados s?smicos

Marinho, Eberton da Silva 22 August 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-03-09T22:35:46Z No. of bitstreams: 1 EbertonDaSilvaMarinho_TESE.pdf: 27289302 bytes, checksum: afbb77aed251ffa31c13cdae992f063a (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-03-13T21:12:47Z (GMT) No. of bitstreams: 1 EbertonDaSilvaMarinho_TESE.pdf: 27289302 bytes, checksum: afbb77aed251ffa31c13cdae992f063a (MD5) / Made available in DSpace on 2017-03-13T21:12:47Z (GMT). No. of bitstreams: 1 EbertonDaSilvaMarinho_TESE.pdf: 27289302 bytes, checksum: afbb77aed251ffa31c13cdae992f063a (MD5) Previous issue date: 2016-08-22 / O Compressive Sensing (CS) ? uma t?cnica de processamento de dados eficiente na recupera??o e constru??o de sinais a partir de uma taxa de amostragem menor que a requerida pelo teorema de Shannon-Nyquist. Esta t?cnica permite uma grande redu??o de dados para sinais que podem ser esparsamente representados. A Transformada Wavelet tem sido utilizada para comprimir e representar muitos sinais naturais, incluindo s?smicos, de uma forma esparsa. H? diversos algoritmos de reconstru??o de sinais que utilizam a t?cnica de CS, como por exemplo: o $\ell_1$-MAGIC, o Fast Bayesian Compressive Sensing (Fast BCS) e o Stagewise Orthogonal Matching Pursuit (StOMP). Esta tese compara a recupera??o de tra?os s?smicos sob uma perspectiva estat?stica usando diferentes m?todos do CS, transformadas wavelets e taxas de amostragens. Mediu-se a correla??o entre o Erro Relativo (ER) de recupera??o pelo CS e as medi??es: coeficiente de varia??o, assimetria, curtose e entropia do sinal original. Parece haver uma correla??o entre a curtose e entropia do sinal com o ER de reconstru??o pelo CS. Ademais, foi analizado a distribui??o do ER no CS. O $\ell_1$-MAGIC teve melhores resultados para taxas de amostragens at? 40%. Al?m disso, a distribui??o do ER no $\ell_1$-MAGIC teve mais histogramas normais, sim?tricos e mesoc?rticos que no Fast BCS. Entretanto, para taxas de amostragem acima de 50%, o Fast BCS mostrou um melhor desempenho em rela??o ? m?dia do ER.

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