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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.
521

Sistema inteligente para apoio ? decis?o na opera??o de uma malha de escoamento de petr?leo

Borges, Roberto Evelim Penha 19 August 2014 (has links)
Made available in DSpace on 2014-12-17T14:08:57Z (GMT). No. of bitstreams: 1 RobertoEPB_DISSERT.pdf: 1009635 bytes, checksum: 353b50f5c3e1f13817d981d7d7a2bb6d (MD5) Previous issue date: 2014-08-19 / The petroleum production pipeline networks are inherently complex, usually decentralized systems. Strict operational constraints are applied in order to prevent serious problems like environmental disasters or production losses. This paper describes an intelligent system to support decisions in the operation of these networks, proposing a staggering for the pumps of transfer stations that compose them. The intelligent system is formed by blocks which interconnect to process the information and generate the suggestions to the operator. The main block of the system uses fuzzy logic to provide a control based on rules, which incorporate knowledge from experts. Tests performed in the simulation environment provided good results, indicating the applicability of the system in a real oil production environment. The use of the stagger proposed by the system allows a prioritization of the transfer in the network and a flow programming / As redes de escoamento da produ??o de petr?leo s?o sistemas comumente descentralizados, inerentemente complexos. Restri??es operacionais r?gidas s?o aplicadas para evitar problemas graves, como desastres ambientais ou perdas de produ??o. Este trabalho descreve um sistema inteligente para auxiliar as decis?es na opera??o dessas malhas, propondo um escalonamento das bombas das esta??es de transfer?ncia que a comp?em. O sistema inteligente ? formado por blocos, que se interligam para processar a informa??o e gerar as sugest?es para o operador. O bloco principal do sistema utiliza a l?gica fuzzy para prover um controle baseado em regras, que incorporam o conhecimento de especialistas. Os testes realizados em ambiente de simula??o obtiveram bons resultados, indicando a aplicabilidade do sistema em um ambiente real de produ??o de petr?leo. O uso do escalonamento proposto pelo sistema permite uma prioriza??o da transfer?ncia na rede e uma programa??o do escoamento
522

Evolu??o diagen?tica e caracteriza??o dos reservat?rios da se??o devoniana na Bacia do Rio do Peixe-Nordeste do Brasil

Silva, Isabelle Teixeira da 04 June 2014 (has links)
Made available in DSpace on 2014-12-17T14:08:57Z (GMT). No. of bitstreams: 1 IsabelleTS_DISSERT.pdf: 9676896 bytes, checksum: 211bb77ead98d9be0d4a700bc3a80049 (MD5) Previous issue date: 2014-06-04 / Universidade Federal do Rio Grande do Norte / The Rio do Peixe Basin represents a main basin of northeastern Brazil and pioneering work positioned the rocks of this basin in the Early Cretaceous. However, a recent study, based on integrated pollen analysis from three wells, found an unprecedented siliciclastic sedimentary section, in the region, of early Devonian age. Therefore, the present study aims a detailed petrographic and petrological analysis of this devonian section, in the Rio do Peixe Basin and proposes a diagenetic evolution, to understand the characteristics of the porous system, identify the main reservoir petrofacies with the main factors impacting on the quality of these rocks as reservoirs and a quick study on the provenance of this section. The petrographic study was based on samples obtained from subsurface and surface. The diagenetic evolution of petrofacies and its identification were based only on subsurface samples and the study of provenance was based on surface samples. The thin sections were prepared from sandstones, pelites and sandstones intercalated with pelites. The original detrital composition for this section is arcosean and the main diagenetic processes that affected these rocks occur in various depths and different conditions, which resulted in extensive diagenetic variety. The following processes were identified: early fracture and healing of grains; albitization of K-feldspar and plagioclase; siderite; precipitation of silica and feldspar; mechanical infiltration of clay and its transformation to illite/esmectite and illite; autigenesis of analcime; dissolution; autigenesis of chlorite; dolomite/ferrous dolomite/anquerite; apatite; calcite; pyrite; titanium minerals and iron oxide-hidroxide. The occurrence of a recently discovered volcanism, in the Rio do Peixe Basin, may have influenced the diagenetic evolution of this section. Three diagenetic stages affected the Devonian section: eo, meso and telodiagenesis. This section is compositionally quite feldspathic, indicating provenance from continental blocks, between transitional continental and uplift of the basement. From this study, we observed a wide heterogeneity in the role of the studied sandstones as reservoirs. Seven petrofacies were identified, taking into account the main diagenetic constituent responsible for the reduction of porosity. It is possible that the loss of original porosity was influenced by intense diagenesis in these rocks, where the main constituent for the loss of porosity are clays minerals, oxides and carbonate cement (calcite and dolomite) / A Bacia do Rio do Peixe corresponde a uma das principais bacias interiores do Nordeste do Brasil e trabalhos pioneiros posicionaram as rochas pertencentes a esta bacia, no Cret?ceo Inferior. Entretanto, um estudo mais recente, baseado na an?lise palinol?gica integrada entre tr?s po?os, verificou a exist?ncia de uma se??o sedimentar silicicl?stica, in?dita na regi?o, de idade eodevoniana. Portanto, o presente trabalho tem como objetivo realizar uma an?lise petrogr?fica e petrol?gica detalhada dessa se??o devoniana rec?m-descoberta na Bacia do Rio do Peixe e sugerir uma evolu??o diagen?tica, a fim de auxiliar no entendimento das caracter?sticas do sistema poroso, identificar as principais petrof?cies de reservat?rios, juntamente com os principais fatores impactantes na qualidade das mesmas e um breve estudo sobre a proveni?ncia dos sedimentos desta bacia. O estudo petrogr?fico foi baseado em amostras de subsuperficie e superf?cie, tendo a interpreta??o da evolu??o diagen?tica e a identifica??o das petrof?cies sido baseadas, apenas, nas amostras de subsuperf?cie. As l?minas petrogr?ficas foram confeccionadas a partir de arenitos, pelitos e arenitos intercalados por pelitos. A composi??o detr?tica original dessa se??o ? arcoseana e os principais processos diagen?ticos que a afetaram ocorreram em diversas profundidades e diferentes condi??es, o que resultou na grande variedade diagen?tica de processos: faturamento precoce e cicatriza??o de gr?os; albitiza??o dos K-feldspatos e plagiocl?sios; siderita; precipita??o de s?lica e feldspato; infiltra??o mec?nica de argila e transforma??o da mesma em ilita/esmectita e ilita; analcima; autig?nese de analcima; dissolu??o; precipita??o de caulinita; compacta??o mec?nica e qu?mica; autig?nese de clorita, dolomita/dolomita ferrosa/anquerita, apatita, calcita, pirita, minerais de tit?nio e ?xido/hidr?xido de ferro. A ocorr?ncia de vulcanismo rec?m-descoberto na Bacia do Rio do Peixe pode ter influenciado a evolu??o diagen?tica desta se??o. Foram identificados tr?s est?gios diagen?ticos: eo-, meso- e telodiag?nese. Essa se??o ? composicionalmente bastante feldsp?tica, indicando proveni?ncia de blocos continentais, entre o continental transicional a soerguimento do embasamento. A partir desse estudo, foi poss?vel verificar uma heterogeneidade no papel como reservat?rio dos arenitos estudados, sendo poss?vel a separa??o de sete petrof?cies, identificadas a partir do principal constituinte diagen?tico respons?vel pela redu??o da porosidade. A perda da porosidade original foi influenciada pela diag?nese intensa nessas rochas, sobretudo pela autig?nese de argilominerais, ?xidos e carbonatos (calcita e dolomita)
523

Implementa??o do algoritmo (RTM) para processamento s?smico em arquiteturas n?o convencionais

Lima, Igo Pedro de 16 June 2014 (has links)
Made available in DSpace on 2014-12-17T14:08:57Z (GMT). No. of bitstreams: 1 IgoPL_DISSERT.pdf: 1338632 bytes, checksum: 5c21a0cb714155a0e215d803dca007ce (MD5) Previous issue date: 2014-06-16 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / With the growth of energy consumption worldwide, conventional reservoirs, the reservoirs called "easy exploration and production" are not meeting the global energy demand. This has led many researchers to develop projects that will address these needs, companies in the oil sector has invested in techniques that helping in locating and drilling wells. One of the techniques employed in oil exploration process is the reverse time migration (RTM), in English, Reverse Time Migration, which is a method of seismic imaging that produces excellent image of the subsurface. It is algorithm based in calculation on the wave equation. RTM is considered one of the most advanced seismic imaging techniques. The economic value of the oil reserves that require RTM to be localized is very high, this means that the development of these algorithms becomes a competitive differentiator for companies seismic processing. But, it requires great computational power, that it still somehow harms its practical success. The objective of this work is to explore the implementation of this algorithm in unconventional architectures, specifically GPUs using the CUDA by making an analysis of the difficulties in developing the same, as well as the performance of the algorithm in the sequential and parallel version / Com o crescimento do consumo energ?tico em todo o mundo, os reservat?rios convencionais, chamados de reservat?rios de f?cil explora??o e produ??o n?o est?o atendendo a demanda energ?tica mundial. Isso tem levado muitos pesquisadores a desenvolver trabalhos que venham sanar essas car?ncias. Empresas do setor petrol?fero tem investido em t?cnicas que ajudem na localiza??o e perfura??o de po?os. Uma das t?cnicas empregadas no processo de explora??o de petr?leo ? a Migra??o Reversa no Tempo (RTM), do ingl?s, Reverse Time Migration, que ? um m?todo de imageamento s?smico que produz excelente imagem de subsuperf?cie. ? um algoritmo baseado no c?lculo da equa??o de onda. A RTM ? considerada uma das t?cnicas mais avan?adas de imageamento s?smico. O valor econ?mico das reservas de petr?leo que requerem RTM para ser localizada ? muito alto, isso significa que o desenvolvimento desses algoritmos torna-se um diferencial competitivo para as empresas de processamento s?smico. No entanto, o mesmo requer grande poder computacional que, de alguma forma, ainda prejudica o seu sucesso pr?tico. Assim, o objetivo deste trabalho ? explorar a implementa??o desse algoritmo em arquiteturas n?o convencionais, especificamente as GPUs, utilizando a plataforma CUDA, fazendo uma an?lise das dificuldades no desenvolvimento do mesmo, bem como a performance do algoritmo na vers?o sequencial e paralela
524

Desenvolvimento de uma unidade pirol?tica com reator de cilindro rotativo: obten??o de bio-?leo

Fontes, L?cio ?ngelo de Oliveira 27 May 2011 (has links)
Made available in DSpace on 2014-12-17T14:09:12Z (GMT). No. of bitstreams: 1 LucioAOF_TESE.pdf: 1700370 bytes, checksum: e23b516b6b57629ea655b3a1c24fcf35 (MD5) Previous issue date: 2011-05-27 / The demand for alternative sources of energy drives the technological development so that many fuels and energy conversion processes before judged as inadequate or even non-viable, are now competing fuels and so-called traditional processes. Thus, biomass plays an important role and is considered one of the sources of renewable energy most important of our planet. Biomass accounts for 29.2% of all renewable energy sources. The share of biomass energy from Brazil in the OIE is 13.6%, well above the world average of participation. Various types of pyrolysis processes have been studied in recent years, highlighting the process of fast pyrolysis of biomass to obtain bio-oil. The continuous fast pyrolysis, the most investigated and improved are the fluidized bed and ablative, but is being studied and developed other types in order to obtain Bio-oil a better quality, higher productivity, lower energy consumption, increased stability and process reliability and lower production cost. The stability of the product bio-oil is fundamental to designing consumer devices such as burners, engines and turbines. This study was motivated to produce Bio-oil, through the conversion of plant biomass or the use of its industrial and agricultural waste, presenting an alternative proposal for thermochemical pyrolysis process, taking advantage of particle dynamics in the rotating bed that favors the right gas-solid contact and heat transfer and mass. The pyrolyser designed to operate in a continuous process, a feeder containing two stages, a divisive system of biomass integrated with a tab of coal fines and a system of condensing steam pyrolytic. The prototype has been tested with sawdust, using a complete experimental design on two levels to investigate the sensitivity of factors: the process temperature, gas flow drag and spin speed compared to the mass yield of bio-oil. The best result was obtained in the condition of 570 oC, 25 Hz and 200 cm3/min, temperature being the parameter of greatest significance. The mass balance of the elementary stages presented in the order of 20% and 37% liquid pyrolytic carbon. We determined the properties of liquid and solid products of pyrolysis as density, viscosity, pH, PCI, and the composition characterized by chemical analysis, revealing the composition and properties of a Bio-oil. / A demanda por fontes alternativas de energia impulsiona o desenvolvimento tecnol?gico de tal forma que muitos combust?veis e processos de convers?o energ?tica, antes julgada como inadequados ou mesmo invi?veis, s?o agora concorrentes de combust?veis e processos ditos tradicionais. Assim, a biomassa exerce um papel relevante, sendo considerada uma das fontes de energia renov?vel mais importante de nosso planeta. A biomassa contribui com 29,2 % de todas as fontes renov?veis de energia. A participa??o de energia de biomassa do Brasil na OIE ? de 13,6 %, sendo bem superior a m?dia mundial de participa??o. V?rios tipos de processos de pir?lise v?m sendo estudados nos ?ltimos anos, destacando-se o processo de pir?lise r?pida de biomassa para obten??o de Bio-?leo. Os processos cont?nuos de pir?lise r?pida, mais investigados e aprimorados s?o os de leito fluidizado e leito ablativo, entretanto vem sendo estudados e desenvolvidos outros tipos, visando obter um bio-?leo de melhor qualidade, com maior produtividade, menor consumo de energia, maior estabilidade e confiabilidade de processo e menor custo de produ??o. A estabilidade do produto Bio-?leo ? fundamental para a concep??o de dispositivos consumidores, tais como queimadores, motores de pist?o e turbinas. O presente estudo foi motivado para a produ??o de Bio-?leo, atrav?s da convers?o da biomassa vegetal ou do aproveitamento de seus res?duos industriais e agr?colas, sendo apresentada uma proposta alternativa de processo de pir?lise termoqu?mica, aproveitando a vantagem din?mica das part?culas no leito rotativo o que favorece a raz?o de contato g?s-s?lido e a transfer?ncia de calor e massa. O pirolisador foi projetado para operar em processo cont?nuo, contendo um alimentador de dois est?gios, um sistema desagregador da biomassa integrado com um separador de finos de carv?o e um sistema de condensa??o de vapores pirol?ticos. O Prot?tipo foi submetido a ensaios com serragem de madeira, utilizando um planejamento experimental completo em dois n?veis para investigar a sensibilidade dos fatores: temperatura do processo, fluxo de g?s de arraste e velocidade de centrifuga??o em rela??o ao rendimento m?ssico de Bio-?leo. O melhor resultado foi obtido na condi??o de 570 oC, 25 Hz e 200 cm3/min, sendo a temperatura o par?metro de maior signific?ncia. O balan?o Tese de Doutorado PPGCEP/UFRN L?cio ?ngelo de Oliveira Fontes vi de massa elementar das fases apresentou da ordem de 20 % liquidos pirol?ticos e 37 % de carv?o. Foram determinadas as propriedades dos produtos l?quidos e s?lidos da pir?lise como densidade, viscosidade, pH, PCI, sendo a composi??o caracterizada atrav?s an?lise qu?mica, revelando as propriedades e composi??o de um Bio-?leo.
525

Contribui??o da Geod?sia ao monitoramento costeiro do Litoral Setentrional do Rio Grande do Norte, ?rea de influ?ncia da ind?stria petrol?fera

Santos, Marcelo Soares Teles 08 July 2011 (has links)
Made available in DSpace on 2014-12-17T14:09:13Z (GMT). No. of bitstreams: 1 MarceloSTS_TESE.pdf: 2868959 bytes, checksum: f60bedf5f558e2aafe77046674684c88 (MD5) Previous issue date: 2011-07-08 / The general objective of this thesis has been seasonal monitoring (quarterly time scale) of coastal and estuarine areas of a section of the Northern Coast of Rio Grande do Norte, Brazil, environmentally sensitive and with intense sediment erosion in the oil activities to underpin the implementation of projects for containment of erosion and mitigate the impacts of coastal dynamics. In order to achieve the general objective, the work was done systematically in three stages which consisted the specific objectives. The first stage was the implementation of geodetic reference infrastructure for carrying out the geodetic survey of the study area. This process included the implementation of RGLS (Northern Coast of the RN GPS Network), consisting of stations with geodetic coordinates and orthometric heights of precision; positioning of Benchmarks and evaluation of the gravimetric geoid available, for use in GPS altimetry of precision; and development of software for GPS altimetry of precision. The second stage was the development and improvement of methodologies for collection, processing, representation, integration and analysis of CoastLine (CL) and Digital Elevation Models (DEM) obtained by geodetic positioning techniques. As part of this stage have been made since, the choice of equipment and positioning methods to be used, depending on the required precision and structure implanted, and the definition of the LC indicator and of the geodesic references best suited, to coastal monitoring of precision. The third step was the seasonal geodesic monitoring of the study area. It was defined the execution times of the geodetic surveys by analyzing the pattern of sediment dynamics of the study area; the performing of surveys in order to calculate and locate areas and volumes of erosion and accretion (sandy and volumetric sedimentary balance) occurred on CL and on the beaches and islands surfaces throughout the year, and study of correlations between the measured variations (in area and volume) between each survey and the action of the coastal dynamic agents. The results allowed an integrated study of spatial and temporal interrelationships of the causes and consequences of intensive coastal processes operating in the area, especially to the measurement of variability of erosion, transport, balance and supply sedimentary over the annual cycle of construction and destruction of beaches. In the analysis of the results, it was possible to identify the causes and consequences of severe coastal erosion occurred on beaches exposed, to analyze the recovery of beaches and the accretion occurring in tidal inlets and estuaries. From the optics of seasonal variations in the CL, human interventions to erosion contention have been proposed with the aim of restoring the previous situation of the beaches in the process of erosion. / O objetivo geral desta Tese de Doutorado foi o monitoramento costeiro sazonal (em escala temporal trimestral) de ?reas costeiras e estuarinas de um trecho do Litoral Setentrional do Estado do Rio Grande do Norte, Brasil, sens?vel ambientalmente e de intensa eros?o sedimentar sob as atividades petrol?feras, para servir de base na implanta??o de projetos de conten??o da eros?o e na mitiga??o dos impactos causados pela din?mica costeira. Para atingir o objetivo geral, o trabalho foi desenvolvido de maneira sistem?tica em tr?s etapas, as quais consistiram os objetivos espec?ficos. A primeira etapa foi da implanta??o da infraestrutura geod?sica de refer?ncia para a realiza??o dos levantamentos geod?sicos da ?rea de estudo. Compreendeu a implanta??o da Rede GPS do Litoral Setentrional do RN (RGLS), constitu?da de esta??es com coordenadas geod?sicas e altitudes ortom?tricas de precis?o; posicionamento de Refer?ncias de N?vel (RN) e avalia??o do modelo geoidal gravim?trico dispon?vel, para serem utilizados na altimetria por GPS de precis?o; e desenvolvimento de aplicativos para a altimetria por GPS de precis?o. A segunda etapa foi do desenvolvimento e aperfei?oamento de metodologias para o levantamento, processamento, representa??o, integra??o e an?lises de Linhas de Costa (LC) e Modelos Digitais de Eleva??o (MDE) obtidos por t?cnicas geod?sicas de posicionamento. Incluiu desde a escolha dos equipamentos e m?todos de posicionamento a serem utilizados, em fun??o da precis?o requerida e da estrutura implantada, at? a defini??o do indicador de LC e dos referenciais geod?sicos mais adequados ao monitoramento costeiro de precis?o. A terceira etapa foi do monitoramento geod?sico sazonal da ?rea de estudo. Definiu as ?pocas de execu??o dos levantamentos geod?sicos, a partir da an?lise do padr?o de din?mica sedimentar da ?rea de estudo; execu??o dos levantamentos, com os objetivos de calcular e localizar ?reas e volumes de eros?o e acres??o (balan?os sedimentares areal e volum?trico) ocorridas nas LC e nas superf?cies das praias e ilhas ao longo do ano, e estudo das correla??es entre as varia??es mensuradas (em ?rea e volume) entre os levantamentos e a atua??o dos agentes din?micos costeiros. Os resultados permitiram um estudo integrado das rela??es espaciais e temporais das causas e consequ?ncias dos intensos processos costeiros atuantes na ?rea, especialmente com a mensura??o da variabilidade da eros?o, transporte, balan?o e suprimento sedimentares ao longo do ciclo anual de constru??o e destrui??o das praias. Nas an?lises dos resultados, foi poss?vel identificar as causas e consequ?ncias da intensa eros?o costeira nas praias expostas, analisar a recupera??o sedimentar das praias e a acres??o nos canais de mar? e nos estu?rios. A partir da ?tica das varia??es sazonais das linhas de costa, interven??es antr?picas de conten??o de eros?o foram propostas com o objetivo de recuperar a situa??o anterior das praias em processo de eros?o.
526

An?lise de viabilidade de inje??o de fluidos alternativos ao vapor em reservat?rios de ?leo pesado

Rodrigues, Marcos Allyson Felipe 03 September 2012 (has links)
Made available in DSpace on 2014-12-17T14:09:14Z (GMT). No. of bitstreams: 1 MarcosAFR_TESE.pdf: 4983695 bytes, checksum: 6cb8867b58e49a5dd6efc85191c6fa49 (MD5) Previous issue date: 2012-09-03 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Many of hydrocarbon reserves existing in the world are formed by heavy oils (?API between 10 and 20). Moreover, several heavy oil fields are mature and, thus, offer great challenges for oil industry. Among the thermal methods used to recover these resources, steamflooding has been the main economically viable alternative. Latent heat carried by steam heats the reservoir, reducing oil viscosity and facilitating the production. This method has many variations and has been studied both theoretically and experimentally (in pilot projects and in full field applications). In order to increase oil recovery and reduce steam injection costs, the injection of alternative fluid has been used on three main ways: alternately, co-injected with steam and after steam injection interruption. The main objective of these injection systems is to reduce the amount of heat supplied to the reservoir, using cheaper fluids and maintaining the same oil production levels. This works discusses the use of carbon dioxide, nitrogen, methane and water as an alternative fluid to the steam. The analyzed parameters were oil recoveries and net cumulative oil productions. The reservoir simulation model corresponds to an oil reservoir of 100 m x 100 m x 28 m size, on a Cartesian coordinates system (x, y and z directions). It is a semi synthetic model with some reservoir data similar to those found in Brazilian Potiguar Basin. All studied cases were done using the simulator STARS from CMG (Computer Modelling Group, version 2009.10). It was found that waterflood after steam injection interruption achieved the highest net cumulative oil compared to other fluids injection. Moreover, it was observed that steam and alternative fluids, co-injected and alternately, did not present increase on profitability project compared with steamflooding / Muitas das reservas de hidrocarbonetos existentes em todo o mundo s?o formadas por ?leos pesados (?API entre 10 e 20). Al?m disso, v?rios campos de ?leo pesado est?o maduros e, portanto, oferecem grandes desafios para a ind?stria do petr?leo. Entre os m?todos t?rmicos utilizados para recuperar estes recursos, a inje??o de vapor tem sido a principal alternativa economicamente vi?vel. O calor latente transportado por meio de vapor aquece o reservat?rio, reduzindo a viscosidade do ?leo, facilitando a produ??o. A fim de aumentar a recupera??o de ?leo e reduzir os custos inerentes ? inje??o de vapor, a inje??o de fluidos alternativos tem sido utilizado em combina??o com o vapor das seguintes formas: alternadamente, coinjetados e ap?s a interrup??o da inje??o de vapor. O objetivo principal destes sistemas de inje??o combinada ? reduzir a quantidade de calor fornecida ao reservat?rio utilizando fluidos de menor valor comercial, buscando manter os n?veis de produ??o de ?leo. Este trabalho analisa o uso do di?xido de carbono, nitrog?nio, metano e ?gua como fluido alternativo ao vapor. Os par?metros analisados foram a recupera??o de ?leo e a produ??o acumulada l?quida. O modelo de reservat?rio analisado corresponde a um reservat?rio de dimens?es 100 m x 100 m x 28 m, num sistema de coordenadas cartesianas ( dire??es x, y e z). ? um modelo semissint?tico com alguns dados de reservat?rio semelhantes aos encontrados na Bacia Potiguar, Brasil. Todos os casos estudados foram simulados utilizando o simulador STARS da CMG (Computer Group, Modelagem vers?o 2009.10). Verificou-se que a inje??o de ?gua ap?s a interrup??o de inje??o de vapor alcan?ou melhores resultados em termos de produ??o acumulada l?quida de ?leo em rela??o a inje??o de outros fluidos. Al?m disso, foi observado que o vapor e os fluidos alternativos, coinjetados e alternados, n?o apresentou aumento na rentabilidade do projeto em compara??o com a inje??o cont?nua de vapor
527

An?lise param?trica da inje??o de vapor e solvente em reservat?rios de ?leo pesado

Galv?o, Edney Rafael Viana Pinheiro 03 September 2012 (has links)
Made available in DSpace on 2014-12-17T14:09:14Z (GMT). No. of bitstreams: 1 EdneyRVPG_TESE.pdf: 5370155 bytes, checksum: 315c7c0efbbd205da67094e4ae12330e (MD5) Previous issue date: 2012-09-03 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / A significant fraction of the hydrocarbon reserves in the world is formed by heavy oils. From the thermal methods used to recovery these resources, Steamflooding has been one of the main economically viable alternatives. In Brazil, this technology is widely used by Petrobras in Northeast fields. Latent heat carried by steam heats the oil in the reservoir, reducing its viscosity and facilitating the production. In the last years, an alternative more and more used by the oil industry to increase the efficiency of this mechanism has been the addition of solvents. When co-injected with steam, the vaporized solvent condenses in the cooler regions of the reservoir and mixes with the oil, creating a low viscosity zone between the steam and the heavy oil. The mobility of the displaced fluid is then improved, resulting in an increase of oil recovery. To better understand this improved oil recovery method and investigate its applicability in reservoirs with properties similar to those found in Potiguar Basin, a numerical study was done to analyze the influence of some operational parameters (steam injection rate, injected solvent volume and solvent type) on oil recovery. Simulations were performed in STARS ("Steam, Thermal, and Advanced Processes Reservoir Simulator"), a CMG ("Computer Modelling Group") program, version 2009.10. It was found that solvents addition to the injected steam not only anticipated the heated oil bank arrival to the producer well, but also increased the oil recovery. Lower cold water equivalent volumes were required to achieve the same oil recoveries from the models that injected only steam. Furthermore, much of the injected solvent was produced with the oil from the reservoir / Uma por??o significativa das reservas de hidrocarbonetos atualmente existentes no mundo ? formada por ?leos pesados. Dentre os m?todos t?rmicos utilizados para a recupera??o desse tipo de recurso, a Inje??o Cont?nua de Vapor tem se constitu?do como uma das principais alternativas economicamente vi?veis. No Brasil, essa tecnologia ? largamente utilizada pela Petrobras em campos localizados na regi?o Nordeste. O calor latente transportado pelo vapor aquece o ?leo do reservat?rio, reduzindo sua viscosidade e facilitando a produ??o. Nos ?ltimos anos, uma alternativa cada vez mais utilizada pela ind?stria para aumentar a efici?ncia desse mecanismo tem sido a adi??o de solventes. Quando coinjetado com o vapor, o solvente vaporizado se condensa nas regi?es menos aquecidas do reservat?rio e mistura-se ao ?leo, criando uma zona de baixa viscosidade entre o vapor e o ?leo pesado. A mobilidade do fluido deslocado ? ent?o melhorada, implicando num aumento da fra??o recuperada. Para melhor compreender esse mecanismo de recupera??o avan?ada e investigar a sua aplicabilidade em reservat?rios com caracter?sticas semelhantes aos encontrados na Bacia Potiguar, foi realizado um estudo num?rico, onde se verificou a influ?ncia de alguns par?metros operacionais (vaz?o de inje??o de vapor, volume de solvente injetado e tipo de solvente) sobre a recupera??o de ?leo. As simula??es foram realizadas no m?dulo STARS ( Steam, Thermal, and Advanced Processes Reservoir Simulator ) do programa da CMG ( Computer Modelling Group ), vers?o 2009.10. Verificou-se que a adi??o de solventes ao vapor injetado n?o s? antecipou a chegada do banco de ?leo aquecido ao po?o produtor como tamb?m incrementou a recupera??o de ?leo. Menores volumes de ?gua fria equivalente foram requeridos para se obter as mesmas fra??es recuperadas dos modelos que s? injetaram vapor. Al?m disso, boa parte do solvente injetado foi produzido juntamente com o ?leo do reservat?rio
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Avalia??o da esp?cie vegetal Croton cajucara Benth como inibidor de biocorros?o em a?o carbono Aisi 1020

Felipe, Maria Beatriz Mesquita Cansan??o 31 July 2012 (has links)
Made available in DSpace on 2014-12-17T14:09:15Z (GMT). No. of bitstreams: 1 MariaBMCF_TESE.pdf: 3590314 bytes, checksum: 61ee9a18f02d6eff55991bb6b1c735a8 (MD5) Previous issue date: 2012-07-31 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Actually in the oil industry biotechnological approaches represent a challenge. In that, attention to metal structures affected by electrochemical corrosive processes, as well as by the interference of microorganisms (biocorrosion) which affect the kinetics of the environment / metal interface. Regarding to economical and environmental impacts reduction let to the use of natural products as an alternative to toxic synthetic inhibitors. This study aims the employment of green chemistry by evaluating the stem bark extracts (EHC, hydroalcoholic extract) and leaves (ECF, chloroform extract) of plant species Croton cajucara Benth as a corrosion inhibitor. In addition the effectiveness of corrosion inhibition of bioactive trans-clerodane dehydrocrotonin (DCTN) isolated from the stem bark of this Croton was also evaluated. For this purpose, carbon steel AISI 1020 was immersed in saline media (3,5 % NaCl) in the presence and absence of a microorganism recovered from a pipeline oil sample. Corrosion inhibition efficiency and its mechanisms were investigated by linear sweep voltammetry and electrochemical impedance. Culture-dependent and molecular biology techniques were used to characterize and identify bacterial species present in oil samples. The tested natural products EHC, ECF and DCTN (DMSO as solvent) in abiotic environment presented respectively, corrosion inhibition efficiencies of 57.6% (500 ppm), 86.1% (500 ppm) and 54.5% (62.5 ppm). Adsorption phenomena showed that EHC best fit Frumkin isotherm and ECF to Temkin isotherm. EHC extract (250 ppm) dissolved in a polar microemulsion system (MES-EHC) showed significant maximum inhibition efficiency (93.8%) fitting Langmuir isotherm. In the presence of the isolated Pseudomonas sp, EHC and ECF were able to form eco-compatible organic films with anti-corrosive properties / Na ind?stria petrol?fera problemas relacionados a processos corrosivos em estruturas met?licas representam um desafio voltado para quest?es biotecnol?gicas. Esses processos podem ser significantemente influenciados pela presen?a de microorganismos que afetam a cin?tica eletroqu?mica da interface ambiente/superf?cie met?lica (biocorros?o). Neste contexto, a substitui??o de inibidores sint?ticos t?xicos por produtos naturais bioaceit?veis constitui uma alternativa economicamente importante com minimiza??o de impactos ambientais. No presente trabalho um dos objetivos principais est? vinculado ao emprego de qu?mica verde, em que foram avaliados extratos da casca do caule (extrato hidroalco?lico denominado de EHC) e folhas (extrato clorof?rmio, ECF) da esp?cie vegetal Croton cajucara Benth. Em adi??o a efic?cia de inibi??o ? corros?o do clerodano bioativo trans-desidrocrotonina (DCTN) isolado das cascas do caule deste Croton tamb?m foi avaliada. Para tanto, utilizou-se a?o carbono AISI 1020 imerso em solu??o salina, sob influ?ncia de microrganismo recuperado de uma amostra de petr?leo, bem como na sua aus?ncia. As efici?ncias de inibi??es ? corros?o e seus mecanismos foram investigados atrav?s das t?cnicas de voltametria de varredura linear e imped?ncia eletroqu?mica. T?cnicas dependentes de cultura e de biologia molecular foram utilizadas na identifica??o de esp?cies bacterianas presentes em amostras de petr?leo. Os extratos EHC, ECF e o composto DCTN veiculados em DMSO, apresentaram respectivamente, efici?ncias de inibi??es ? corros?o em meio abi?tico, com m?ximas de 57,6% (500 ppm), 86,1% (500 ppm) e 54,5% (62,5 ppm). Com rela??o ao processo de adsor??o, EHC se ajustou a isoterma de Frumkin e ECF a isoterma de Temkin. No entanto, o extrato EHC (250 ppm) veiculado em uma microemuls?o polar (SME-EHC) com efici?ncia m?xima de inibi??o 93,8%, se ajustou a isoterma de Langmuir. Na presen?a da esp?cie bacteriana caracterizada Pseudomonas sp., os extratos EHC e ECF formaram filmes ecocompat?veis protetores com a??o anti-corrosiva
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Metodologia para avalia??o de cinem?tica de part?culas gasosas em fluidos de viscosidade vari?vel com o tempo e sua aplica??o na constru??o de po?os de petr?leo

Pinto, Gustavo Henrique Vieira Pereira 17 December 2012 (has links)
Made available in DSpace on 2014-12-17T14:09:15Z (GMT). No. of bitstreams: 1 GustavoHVPP_TESE.pdf: 1614621 bytes, checksum: 41665985b97dd379d0430f1b97b534b6 (MD5) Previous issue date: 2012-12-17 / Many challenges have been presented in petroleum industry. One of them is the preventing of fluids influx during drilling and cementing. Gas migration can occur as result of pressure imbalance inside the well when well pressure becomes lower than gas zone pressure and in cementing operation this occurs during cement slurry transition period (solid to fluid). In this work it was developed a methodology to evaluate gas migration during drilling and cementing operations. It was considered gel strength concept and through experimental tests determined gas migration initial time. A mechanistic model was developed to obtain equation that evaluates bubble displacement through the fluid while it gels. Being a time-dependant behavior, dynamic rheological measurements were made to evaluate viscosity along the time. For drilling fluids analyzed it was verified that it is desirable fast and non-progressive gelation in order to reduce gas migration without affect operational window (difference between pore and fracture pressure). For cement slurries analyzed, the most appropriate is that remains fluid for more time below critical gel strength, maintaining hydrostatic pressure above gas zone pressure, and after that gels quickly, reducing gas migration. The model developed simulates previously operational conditions and allow changes in operational and fluids design to obtain a safer condition for well construction / Muitos desafios t?m sido apresentados na constru??o de po?os, dentre eles o de evitar o influxo de fluidos durante a perfura??o e cimenta??o. A migra??o de g?s ? resultante do desequil?brio de press?es dentro do po?o, quando a press?o do po?o se torna menor que a da zona contendo o g?s, e na cimenta??o isso ocorre durante o per?odo de transi??o da pasta (de fluido para s?lido). Nesse trabalho foi desenvolvida uma metodologia para avaliar a criticidade da migra??o de g?s durante a perfura??o e opera??es de cimenta??o de po?os. Foi considerado o conceito de for?a gel e atrav?s de ensaios experimentais, determinado o tempo inicial da migra??o de g?s. Foi desenvolvido um modelo mecanicista para obter a equa??o que avalia o deslocamento da bolha atrav?s dos fluidos enquanto eles gelificam. Por ser um comportamento dependente do tempo, foram feitos ensaios reol?gicos din?micos de viscosidade em fun??o do tempo. Para os fluidos de perfura??o analisados verificou-se que ? desej?vel que possuam uma gelifica??o r?pida e n?o progressiva de forma a reduzir a migra??o de g?s sem comprometer a janela operacional (diferen?a entre press?o de poros e fratura). Para as pastas analisadas verificou-se que a mais adequada ? a que se mant?m fluida por mais tempo abaixo do valor do gel cr?tico, mantendo a press?o hidrost?tica acima da press?o da zona de g?s, e ao atingir esse valor, gelifique rapidamente, reduzindo a migra??o de g?s. O modelo permite simular previamente as condi??es operacionais e propor mudan?as no projeto da opera??o e dos fluidos de forma a obter a condi??o mais segura para a constru??o do po?o
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Sistema inteligente para estimar a porosidade em sedimentos a partir da an?lise de sinais GPR

Ara?jo, Eduardo Henrique Silveira de 25 January 2013 (has links)
Made available in DSpace on 2014-12-17T14:09:15Z (GMT). No. of bitstreams: 1 EduardoHSA_TESE3red.pdf: 5316067 bytes, checksum: 9b841153bb325e14b32dc463a70e5a45 (MD5) Previous issue date: 2013-01-25 / This Thesis presents the elaboration of a methodological propose for the development of an intelligent system, able to automatically achieve the effective porosity, in sedimentary layers, from a data bank built with information from the Ground Penetrating Radar GPR. The intelligent system was built to model the relation between the porosity (response variable) and the electromagnetic attribute from the GPR (explicative variables). Using it, the porosity was estimated using the artificial neural network (Multilayer Perceptron MLP) and the multiple linear regression. The data from the response variable and from the explicative variables were achieved in laboratory and in GPR surveys outlined in controlled sites, on site and in laboratory. The proposed intelligent system has the capacity of estimating the porosity from any available data bank, which has the same variables used in this Thesis. The architecture of the neural network used can be modified according to the existing necessity, adapting to the available data bank. The use of the multiple linear regression model allowed the identification and quantification of the influence (level of effect) from each explicative variable in the estimation of the porosity. The proposed methodology can revolutionize the use of the GPR, not only for the imaging of the sedimentary geometry and faces, but mainly for the automatically achievement of the porosity one of the most important parameters for the characterization of reservoir rocks (from petroleum or water) / Esta tese apresenta a elabora??o de uma proposta metodol?gica para o desenvolvimento de um sistema inteligente, capaz de obter automaticamente a porosidade efetiva, em camadas sedimentares, a partir de um banco de dados constru?do com informa??es do Radar de Penetra??o no Solo (Ground Penetrating Radar GPR). O sistema inteligente foi constru?do para modelar a rela??o entre a porosidade (vari?vel resposta) e os atributos eletromagn?ticos do GPR (vari?veis explicativas). Com ele foi estimada a porosidade utilizando modelo de rede neural artificial (Multilayer Perceptron - MLP) e regress?o linear m?ltipla. Os dados da vari?vel resposta e das vari?veis explicativas foram obtidos em laborat?rio e em levantamentos GPR delineados em s?tios controlados em campo e laborat?rio. O sistema inteligente proposto possui a capacidade de estimar a porosidade a partir de qualquer banco de dados dispon?vel, que envolvam as mesmas vari?veis utilizadas nesta tese. A arquitetura da rede neural utilizada pode ser modificada de acordo com a necessidade existente, adequando-se aos bancos de dados dispon?veis. A utiliza??o do Modelo de Regress?o Linear M?ltipla permitiu que fosse identificada e quantificada a influ?ncia (grau de efeito) de cada vari?vel explicativa na estimativa da porosidade. A metodologia proposta pode revolucionar o uso do GPR por permitir, n?o apenas o imageamento das geometrias e f?cies sedimentares, mas principalmente a obten??o autom?tica da porosidade um dos par?metros mais importantes na caracteriza??o de rochas reservat?rios (petrol?feros ou aqu?feros)

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