Much effort of reservoir engineers is devoted to the time-consuming process of history matching in a simulator to understand the reservoir complexity. Its accuracy is debatable because only a few inputs are known. Several analytical tools have been developed to investigate reservoir heterogeneity. The reciprocal productivity index (RPI) is a tool to measure the pressure support observed at a producer. The log (water-oil ratio or WOR) plot can be used to indicate the presence of a channel. A capacitance-resistance model (CRM) is a simple tool to estimate the connectivity between a producer-injector pair from the production/injection and pressure data. Generally field operators implement an improved recovery plan such as water-alternating-gas (WAG) flood to improve displacement efficiency. However, the existence of heterogeneity compromises its performance. The first objective of this study is to improve the assessment of tertiary flood performance by integrating the CRM with other analytical tools. The integrated method was applied to a miscible flood field in West Texas. The results suggest strong interwell connectivity found more frequently in the NE-SW direction and the different preferential flow paths of injected CO2 and water. Overall, the results provide insights into the current flood status. The operating conditions of a producer dynamically change because of well/field constraints. These changes can induce significant interference in other wells, which cannot be captured by CRM. The second objective of this study is to develop a capacitance-resistance model with producer-producer interaction (CRMP-P). The CRMP-P, derived from the continuity and Darcy’s equations, accounts for producer-producer interactions. The CRMP-P was applied to data from three different reservoir models. The results suggest that the CRMP-P could fit the data with higher precision than CRM. Consequently, the CRMP-P estimates of reservoir properties are more accurate. Moreover, the estimated transmissibility between producers is in agreement with the reservoir models. The CRMP-P was also applied to Omani field data. The transmissibility results are consistent with previous study and the drilling information. The more accurate information on producer-producer interactions and reservoir properties can assist in history-matching, locating infill wells, and reservoir management planning. / text

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-11-03T20:19:55Z No. of bitstreams: 1 MarceloPenninckJunior_DISSERT.pdf: 4962702 bytes, checksum: a2db0f3ce929b06142a4528f4e7fc8ba (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-11-16T22:42:16Z (GMT) No. of bitstreams: 1 MarceloPenninckJunior_DISSERT.pdf: 4962702 bytes, checksum: a2db0f3ce929b06142a4528f4e7fc8ba (MD5) / Made available in DSpace on 2017-11-16T22:42:16Z (GMT). No. of bitstreams: 1 MarceloPenninckJunior_DISSERT.pdf: 4962702 bytes, checksum: a2db0f3ce929b06142a4528f4e7fc8ba (MD5) Previous issue date: 2017-07-25 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / As grandes reservas de ?leo leve encontradas em campos brasileiros tamb?m t?m uma quantidade significativa de CO2 dissolvido. Este CO2, quando produzido, pode ser tratado e liberado ou reutilizado como g?s de inje??o no processo de inje??o alternada de ?gua e g?s WAG-CO2. Neste contexto este estudo busca utilizar a inje??o WAG-CO2 imisc?vel em condi??es semelhantes ?s encontradas no campo Sergi-C da bacia de Buracica, alta press?o e baixa temperatura, para cria??o de um modelo de simula??o de reservat?rio onde ser?o analisados os par?metros ligados a histerese da permeabilidade relativa. Para isso foi modelado um ?leo leve, semelhante ao encontrado neste campo, um reservat?rio homog?neo com caracter?sticas semelhantes ao reservat?rio de Buracica, produzindo atrav?s de uma malha 5-spot invertida em um projeto de 20 anos. Dois modelos de histerese da permeabilidade relativa foram estudados, o modelo de Killough (1976) e o modelo de Larsen e Skauge (1998). Uma an?lise de cada par?metro desses modelos mostrou que em alguns casos, pode existir um fator de recupera??o de 98% de ?leo e em outros casos a histerese pode determinar um d?ficit na recupera??o de ?leo de mais de 20%. / The great reserves of light oil found on Brazilian fields also has a significative amount of CO2 dissolved. This CO2, when produced can be treated and released or reused on the process of water alternating gas injection WAG. In this context, this study use WAG-CO2 immiscible injection in similar conditions to those found on Sergi-C field, high pressure and low temperatures, to create a model for reservoir simulation where will be analyzed parameters of relative permeability hysteresis. For this was modeled a light oil, similar to this field, a homogeneous reservoir with similar characteristics to Buracica reservoir found on Bahia concave, producing from an inverted 5-spot mash with 20 years of project. Two models of relative permeability hysteresis were studied, Killough (1976) model and Larsen and Skauge (1998) model. An analyzis of each parameter of those models showed that, in a few cases, there can be an oil recovery factor up to 98% while at others, the hysteresis can determine a deficit on oil recovery of more than 20%.

Die Informationen über das politische und gesellschaftliche Geschehen in der Welt erhalten wir über die Medien. Sie bestimmen, wie wir uns die Welt vorstellen und was wir über sie denken. Aber was zeigen uns die Medien wirklich? Der Film ‘Wag the Dog’ von Regisseur Barry Levinson zeigt, wie in den Medien ein Krieg erfunden wird. Profis konstruieren eine Videoaufnahme und emotionale Nachrichten. Nichts davon ist wahr. Auf den ersten Blick wirkt dieses Szenario als übertriebene Fiktion. Doch nach einer Auseinandersetzung mit den Strategien bewusster journalistischer Konstruktivität im Medienalltag und einer Betrachtung der strukturellen Kopplung zwi-schen Medien und Politik scheint der Film Tendenzen unserer Wirklichkeit zu skizzieren. / Today, information about worldwide events in politics and society are transferred to us by the media. Media determine how we construct the world we are living in and what we think about it. However, what is presented to us by the media? The film ‘Wag the Dog’ by director Barry Levinson shows how war is created by the media. Professionals construct a video tape and emotional news, which are not true. At first sight, this scenario seems to be exaggerated fiction. However, after a close analysis of the strategies used to consciously construct reality in the media and a study of the structural relation between media and politics, this film seems to outline tendencies of our reality.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-05-03T23:46:47Z No. of bitstreams: 1 AnthonyAndreyRamalhoDiniz_TESE.pdf: 15099373 bytes, checksum: 616c247460cf0f6003f86c2374d07108 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-05-05T23:03:00Z (GMT) No. of bitstreams: 1 AnthonyAndreyRamalhoDiniz_TESE.pdf: 15099373 bytes, checksum: 616c247460cf0f6003f86c2374d07108 (MD5) / Made available in DSpace on 2016-05-05T23:03:00Z (GMT). No. of bitstreams: 1 AnthonyAndreyRamalhoDiniz_TESE.pdf: 15099373 bytes, checksum: 616c247460cf0f6003f86c2374d07108 (MD5) Previous issue date: 2015-08-10 / Em 2006, a Petrobras anunciou a descoberta do campo de Tupi, na Bacia de Santos, que concentra uma grande quantidade de petr?leo abaixo da camada de sal, conhecida como camada pr?-sal. Essa descoberta possui grandes volumes de ?leo leve (28? a 30? API), com alto conte?do de g?s, pr?xima aos centros consumidores mais importantes do Sudeste do Brasil e tendo os testes de forma??o dos primeiros po?os apresentado altas vaz?es, sem indica??o de barreiras. Apesar dessa descoberta ser muito importante, a Petrobras e seus parceiros reconhecem que ela representa um cen?rio desafiador, por estar localizada em torno de 300km da costa, em condi??es adversas para sua produ??o. Examinando poss?veis m?todos de recupera??o avan?ada aplic?veis ?quelas condi??es, considerou-se que a presen?a de di?xido de carbono (CO2) poderia ser vantajosa, se combinada com a ?gua do mar, no processo de inje??o alternada de ?gua e g?s (WAG), que passou a ser visto como uma boa op??o. Nesse contexto, esta pesquisa teve como objetivo a realiza??o da avalia??o de v?rias t?cnicas de inje??o de CO2 e ?gua, em reservat?rios com caracter?sticas do pr?-sal brasileiro. Para tanto, foi modelado um ?leo leve, semelhante aos ?leos encontrados na camada do pr?-sal, e um reservat?rio homog?neo, semissint?tico, tamb?m de caracter?sticas semelhantes aos reservat?rios carbon?ticos daquela regi?o, produzindo atrav?s de uma malha five-spot, em um tempo de projeto de 12 anos. Inicialmente, foram realizados testes injetando apenas ?gua e depois CO2. Com base nesses testes, foram avaliadas quatro varia??es do WAG, sendo as duas primeiras com inje??o alternada dos fluidos e as demais com inje??o cont?nua. Ao final, verificou-se que a inje??o alternada de ?gua e g?s, iniciada com ?gua, ? a op??o com maior recupera??o de ?leo, que alcan?ou 91,34% no melhor caso. Quando iniciado com inje??o de g?s, o mesmo processo se torna mais r?pido para intervalos mais curtos, mas n?o resulta na mesma efici?ncia. Por fim, os processos com inje??o cont?nua apresentam resultados mais r?pidos que a inje??o individual dos fluidos, mas o resultado final do CO2 ? superior.

Hybrid gas/chemical Enhanced Oil Recovery (EOR) methods are such novel techniques to increase oil production and oil recovery efficiency. Gas flooding using carbon dioxide, nitrogen, flue gas, and enriched natural gas produce more oil from the reservoirs by channeling gas into previously by-passed areas. Surfactant flooding can recover trapped oil by reducing the interfacial tension between oil and water phases. Hybrid gas/chemical EOR methods benefit from using both chemical and gas flooding. In hybrid gas/chemical EOR processes, surfactant solution is injected with gas during low-tension-gas or foam flooding. Polymer solution can also be injected alternatively with gas to improve the gas volumetric sweep efficiency. Most fundamentally, wide applications of hybrid gas/chemical processes are limited due to uncertainties in reservoir characterization and heterogeneity, due to the lack of understanding of the process and consequently lack of a predictive reservoir simulator to mechanistically model the process. Without a reliable simulator, built on mechanisms determined in the laboratory, promising field candidates cannot be identified in advance nor can process performance be optimized. In this research, UTCHEM was modified to model four-phase water, oil, microemulsion, and gas phases to simulate and interpret chemical EOR processes including free and/or solution gas. We coupled the black-oil model for water/oil/gas equilibrium with microemulsion phase behavior model through a new approach. Four-phase fluid properties, relative permeability, and capillary pressure were developed and implemented. The mass conservation equation was solved for total volumetric concentration of each component at standard conditions and pressure equation was derived for both saturated and undersaturated PVT conditions. To model foam flow in porous media, comprehensive research was performed comparing capabilities and limitations of implicit texture (IT) and population-balance (PB) foam models. Dimensionless foam bubble density was defined in IT models to derive explicitly the foam-coalescence-rate function in these models. Results showed that each of the IT models examined was equivalent to the LE formulation of a population-balance model with a lamella-destruction function that increased abruptly in the vicinity of the limiting capillary pressure, as in current population-balance models. Foam models were incorporated in UTCHEM to model low-tension-gas and foam flow processes in laboratory and field scales. The modified UTCEM reservoir simulator was used to history match published low-tension-gas and foam coreflood experiments. The simulations were also extended to model and evaluate hybrid gas/chemical EOR methods in field scales. Simulation results indicated a well-designed low-tension-gas flooding has the potential to recover the trapped oil where foam provides mobility control during surfactant and surfactant-alkaline flooding in reservoirs with very low permeability. / text

Die Informationen über das politische und gesellschaftliche Geschehen in der Welt erhalten wir über die Medien. Sie bestimmen, wie wir uns die Welt vorstellen und was wir über sie denken. Aber was zeigen uns die Medien wirklich? Der Film ‘Wag the Dog’ von Regisseur Barry Levinson zeigt, wie in den Medien ein Krieg erfunden wird. Profis konstruieren eine Videoaufnahme und emotionale Nachrichten. Nichts davon ist wahr. Auf den ersten Blick wirkt dieses Szenario als übertriebene Fiktion. Doch nach einer Auseinandersetzung mit den Strategien bewusster journalistischer Konstruktivität im Medienalltag und einer Betrachtung der strukturellen Kopplung zwi-schen Medien und Politik scheint der Film Tendenzen unserer Wirklichkeit zu skizzieren. / Today, information about worldwide events in politics and society are transferred to us by the media. Media determine how we construct the world we are living in and what we think about it. However, what is presented to us by the media? The film ‘Wag the Dog’ by director Barry Levinson shows how war is created by the media. Professionals construct a video tape and emotional news, which are not true. At first sight, this scenario seems to be exaggerated fiction. However, after a close analysis of the strategies used to consciously construct reality in the media and a study of the structural relation between media and politics, this film seems to outline tendencies of our reality.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Neste trabalho é apresentado um novo método acurado com passo de tempo fracionário, baseado em uma técnica de decomposição de operadores, para a solução numérica de um sistema governante de equações diferenciais parciais que modela escoamento trifásico água-gás-óleo imiscível em reservatórios de petróleo heterogêneos no qual os efeitos de compressibilidade do gás não foram levados em conta. A técnica de decomposição de operadores em dois níveis permite o uso de passos de tempo distintos para os três problemas definidos pelo procedimento de decomposição: convecção, difusão e pressão-velocidade. Um sistema hiperbólico de leis de conservação que modela o transporte convectivo das fases fluidas é aproximado por um esquema central de diferenças finitas explícito, conservativo, não oscilatório e de segunda ordem. Este esquema é combinado com elementos finitos mistos, localmente conservativos, para a aproximação numérica dos sistemas de equações parabólico e elíptico associados aos problemas de transporte difusivo e de pressão-velocidade, respectivamente. O operador temporal associado ao sistema parabólico é resolvido fazendo-se uso de uma estratégia implícita de solução (Backward Euler). O modelo matemático para escoamento trifásico considerado neste trabalho leva em conta as forças de capilaridade e expressões gerais para as funções de permeabilidade relativa, campos variáveis de porosidade e de permeabilidade e os efeitos da gravidade. A escolha de expressões gerais para as funções de permeabilidade relativa pode levar à perda de hiperbolicidade escrita e, desta maneira, à existência de uma região elíptica ou de pontos umbílicos para o sistema não linear de leis de conservação hiperbólicas que descreve o transporte convectivo das fases fluidas. Como consequência, a perda de hiperbolicidade pode levar à existência de choques não clássicos (também chamados de choques transicionais ou choques subcompressivos) nas soluções de escoamentos trifásicos. O novo procedimento numérico foi usado para investigar a existência e a estabilidade de choques não clássicos, com respeito ao fenômeno de fingering viscoso, em problemas de escoamentos trifásicos bidimensionais em reservatórios heterogêneos, estendendo deste modo resultados disponíveis na literatura para problemas de escoamentos trifásicos unidimensionais. Experimentos numéricos, incluindo o estudo de estratégias de injeção alternada de água e gás (Water-Alternating-Gas (WAG)), indicam que o novo procedimento numérico proposto conduz com eficiência computacional a resultados numéricos com precisão. Perspectivas para trabalhos de pesquisa futuros são também discutidas, tomando como base os desenvolvimentos reportados nesta tese. / We present a new, accurate fractional time-step method based on an operator splitting technique for the numerical solution of a system of partial differential equations modeling three-phase immiscible water-gas-oil flow problems in heterogeneous petroleum reservoirs in which the compressibility effects of the gas was not take into account. A two-level operator splitting technique allows for the use of distinct time steps for the three problems defined by the splitting procedure: convection, diffusion and pressure-velocity. A system of hyperbolic conservation laws modelling the convective transport of the fluid phases is approximated by a high resolution, nonoscillatory, second-order, conservative central difference scheme in the convection step. This scheme is combined with locally conservative mixed finite elements for the numerical solution of the parabolic and elliptic problems associated with the diffusive transport of fluid phases and the pressure-velocity problem, respectively. The time discretization of the parabolic problem is performed by means of the implicit backward Euler method. The mathematical model for the three-phase flow considered in this work takes into account capillary forces and general expressions for the relative permeability functions, variable porosity and permeability fields, and the effect of gravity. The choice of general expressions for the relative permeability functions may lead to the loss of strict hyperbolicity and, therefore, to the existence of an elliptic region of umbilic points for the systems of nonlinear hyperbolic conservation laws describing the convective transport of the fluid phases. As a consequence, the loss of hyperbolicity may lead to the existence of nonclassical shocks (also called transitional shocks or undercompressive shocks) in three-phase flow solutions. The numerical procedure was used in an investigation of the existence and stability of nonclassical shocks with respect to viscous fingering in heterogeneous two-dimensional flows, thereby extending previous results for one-dimensional three-phase flow available in the literature. Numerical experiments, including the study of Water-Alternating-Gas (WAG) injection strategies, indicate that the proposed new numerical procedure leads to computational efficiency and accurate numerical results. Directions for further research are also discussed, based on the developments reported in this thesis.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Neste trabalho é apresentado um novo método acurado com passo de tempo fracionário, baseado em uma técnica de decomposição de operadores, para a solução numérica de um sistema governante de equações diferenciais parciais que modela escoamento trifásico água-gás-óleo imiscível em reservatórios de petróleo heterogêneos no qual os efeitos de compressibilidade do gás não foram levados em conta. A técnica de decomposição de operadores em dois níveis permite o uso de passos de tempo distintos para os três problemas definidos pelo procedimento de decomposição: convecção, difusão e pressão-velocidade. Um sistema hiperbólico de leis de conservação que modela o transporte convectivo das fases fluidas é aproximado por um esquema central de diferenças finitas explícito, conservativo, não oscilatório e de segunda ordem. Este esquema é combinado com elementos finitos mistos, localmente conservativos, para a aproximação numérica dos sistemas de equações parabólico e elíptico associados aos problemas de transporte difusivo e de pressão-velocidade, respectivamente. O operador temporal associado ao sistema parabólico é resolvido fazendo-se uso de uma estratégia implícita de solução (Backward Euler). O modelo matemático para escoamento trifásico considerado neste trabalho leva em conta as forças de capilaridade e expressões gerais para as funções de permeabilidade relativa, campos variáveis de porosidade e de permeabilidade e os efeitos da gravidade. A escolha de expressões gerais para as funções de permeabilidade relativa pode levar à perda de hiperbolicidade escrita e, desta maneira, à existência de uma região elíptica ou de pontos umbílicos para o sistema não linear de leis de conservação hiperbólicas que descreve o transporte convectivo das fases fluidas. Como consequência, a perda de hiperbolicidade pode levar à existência de choques não clássicos (também chamados de choques transicionais ou choques subcompressivos) nas soluções de escoamentos trifásicos. O novo procedimento numérico foi usado para investigar a existência e a estabilidade de choques não clássicos, com respeito ao fenômeno de fingering viscoso, em problemas de escoamentos trifásicos bidimensionais em reservatórios heterogêneos, estendendo deste modo resultados disponíveis na literatura para problemas de escoamentos trifásicos unidimensionais. Experimentos numéricos, incluindo o estudo de estratégias de injeção alternada de água e gás (Water-Alternating-Gas (WAG)), indicam que o novo procedimento numérico proposto conduz com eficiência computacional a resultados numéricos com precisão. Perspectivas para trabalhos de pesquisa futuros são também discutidas, tomando como base os desenvolvimentos reportados nesta tese. / We present a new, accurate fractional time-step method based on an operator splitting technique for the numerical solution of a system of partial differential equations modeling three-phase immiscible water-gas-oil flow problems in heterogeneous petroleum reservoirs in which the compressibility effects of the gas was not take into account. A two-level operator splitting technique allows for the use of distinct time steps for the three problems defined by the splitting procedure: convection, diffusion and pressure-velocity. A system of hyperbolic conservation laws modelling the convective transport of the fluid phases is approximated by a high resolution, nonoscillatory, second-order, conservative central difference scheme in the convection step. This scheme is combined with locally conservative mixed finite elements for the numerical solution of the parabolic and elliptic problems associated with the diffusive transport of fluid phases and the pressure-velocity problem, respectively. The time discretization of the parabolic problem is performed by means of the implicit backward Euler method. The mathematical model for the three-phase flow considered in this work takes into account capillary forces and general expressions for the relative permeability functions, variable porosity and permeability fields, and the effect of gravity. The choice of general expressions for the relative permeability functions may lead to the loss of strict hyperbolicity and, therefore, to the existence of an elliptic region of umbilic points for the systems of nonlinear hyperbolic conservation laws describing the convective transport of the fluid phases. As a consequence, the loss of hyperbolicity may lead to the existence of nonclassical shocks (also called transitional shocks or undercompressive shocks) in three-phase flow solutions. The numerical procedure was used in an investigation of the existence and stability of nonclassical shocks with respect to viscous fingering in heterogeneous two-dimensional flows, thereby extending previous results for one-dimensional three-phase flow available in the literature. Numerical experiments, including the study of Water-Alternating-Gas (WAG) injection strategies, indicate that the proposed new numerical procedure leads to computational efficiency and accurate numerical results. Directions for further research are also discussed, based on the developments reported in this thesis.