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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.
151

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.
152

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.
153

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
154

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
155

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
156

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
157

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)
158

Controle aplicado a po?os com m?todo de eleva??o e bombeio centr?fugo submerso

Costa, Rut?cio de Oliveira 13 July 2012 (has links)
Made available in DSpace on 2014-12-17T14:09:15Z (GMT). No. of bitstreams: 1 RutacioOC_TESE_PARCIAL.pdf: 408685 bytes, checksum: 5bea29db0102078f885dab06d8188a0f (MD5) Previous issue date: 2012-07-13 / The Electrical Submersible Pumping is an artificial lift method for oil wells employed in onshore and offshore areas. The economic revenue of the petroleum production in a well depends on the oil flow and the availability of lifting equipment. The fewer the failures, the lower the revenue shortfall and costs to repair it. The frequency with which failures occur depends on the operating conditions to which the pumps are submitted. In high-productivity offshore wells monitoring is done by operators with engineering support 24h/day, which is not economically viable for the land areas. In this context, the automation of onshore wells has clear economic advantages. This work proposes a system capable of automatically control the operation of electrical submersible pumps, installed in oil wells, by an adjustment at the electric motor rotation based on signals provided by sensors installed on the surface and subsurface, keeping the pump operating within the recommended range, closest to the well s potential. Techniques are developed to estimate unmeasured variables, enabling the automation of wells that do not have all the required sensors. The automatic adjustment, according to an algorithm that runs on a programmable logic controller maintains the flow and submergence within acceptable parameters avoiding undesirable operating conditions, as the gas interference and high engine temperature, without need to resort to stopping the engine, which would reduce the its useful life. The control strategy described, based on modeling of physical phenomena and operational experience reported in literature, is materialized in terms of a fuzzy controller based on rules, and all generated information can be accompanied by a supervisory system / O bombeio centr?fugo submerso ? um m?todo de eleva??o artificial de petr?leo empregado em ?reas terrestres ou mar?timas. A receita econ?mica da produ??o de petr?leo em um po?o depende da vaz?o de ?leo e da disponibilidade do equipamento de eleva??o. Quanto menos falhas, menores ser?o as receitas cessantes e os custos para repar?-las. A frequ?ncia com que as falhas ocorrem depende das condi??es operacionais ?s quais as bombas s?o submetidas. Em po?os mar?timos de alta produtividade o acompanhamento ? feito por operadores com suporte de engenharia 24h/dia, o que n?o ? economicamente vi?vel para as ?reas terrestres. Nesse contexto, a automa??o de po?os terrestres apresenta vantagens econ?micas claras. Neste trabalho ? proposto um sistema capaz de controlar automaticamente a opera??o de bombas centr?fugas submersas instaladas em po?os produtores de petr?leo, via ajuste na rota??o do motor el?trico, a partir de sensores instalados na superf?cie e subsuperf?cie, mantendo a bomba operando dentro da faixa recomendada, o mais pr?ximo poss?vel do potencial do po?o. S?o desenvolvidas t?cnicas de estimativa de vari?veis n?o medidas, possibilitando a automa??o de po?os que n?o possuem todos os sensores requeridos. O ajuste autom?tico, conforme um algoritmo que ? executado em um controlador l?gico program?vel, mant?m a vaz?o e a submerg?ncia dentro de par?metros aceit?veis, evitando condi??es operacionais indesej?veis como a interfer?ncia de g?s e a elevada temperatura do motor, sem a necessidade de recorrer ao desligamento do motor, o que reduziria a sua vida ?til. A estrat?gia de controle descrita, baseada na modelagem dos fen?menos f?sicos e na experi?ncia operacional registrada na literatura, ? materializada em termos de um controlador Fuzzy baseado em regras, sendo que todas as informa??es geradas podem ser acompanhadas por um sistema supervis?rio
159

Pir?lise de borras oleosas de petroleo utilizando nanomateriais

Lima, Cicero de Souza 21 March 2014 (has links)
Made available in DSpace on 2014-12-17T14:09:17Z (GMT). No. of bitstreams: 1 CiceroSL_TESE.pdf: 5334902 bytes, checksum: 41714ced8f45a82dbc84b8d2449a7bee (MD5) Previous issue date: 2014-03-21 / The oily sludge is a complex mix of hydrocarbons, organic impurities, inorganic and water. One of the major problems currently found in petroleum industry is management (packaging, storage, transport and fate) of waste. The nanomaterials (catalysts) mesoporous and microporous are considered promising for refining and adsorbents process for environment protection. The aim of this work was to study the oily sludge from primary processing (raw and treated) and vacuum residue, with application of thermal analyses technique (pyrolysis), thermal and catalytic pyrolysis with nanomaterials, aiming at production petroleum derived. The sludge and vacuum residue were analyzed using a soxhlet extraction system, elemental analysis, thin layer chromatography, thermogravimetry and pyrolysis coupled in gas chromatography/mass spectrometry (Py GC MS). The catalysts AlMCM-41, AlSBA-15.1 e AlSBA-15.2 were synthesized with molar ratio silicon aluminum of 50 (Si/Al = 50), using tetraethylorthosilicante as source of silicon and pseudobuhemita (AlOOH) as source of aluminum. The analyzes of the catalysts indicate that materials showed hexagonal structure and surface area (783,6 m2/g for AlMCM-41, 600 m2/g for AlSBA-15.1, 377 m2/g for AlSBA-15.2). The extracted oily sludge showed a range 65 to 95% for organic components (oil), 5 to 35% for inorganic components (salts and oxides) and compositions different of derivatives. The AlSBA-15 catalysts showed better performance in analyzes for production petroleum derived, 20% increase in production of kerosene and light gas oil. The energy potential of sludge was high and it can be used as fuel in other cargo processed in refinery / A borra oleosa (BO) de petr?leo ? uma mistura complexa de hidrocarbonetos, impurezas org?nicas, inorg?nicas e ?gua. Um dos grandes problemas encontrados atualmente na ind?stria de petr?leo ? o gerenciamento (acondicionamento, armazenamento, transporte e destino) de res?duos. Os nanomateriais (catalisadores) mesoporosos e microporosos s?o considerados promissores em processos de refino de petr?leo e como adsorventes para prote??o ambiental. O objetivo deste trabalho foi estudar a BO de petr?leo oriunda do processamento prim?rio (bruta e tratada) e res?duo de v?cuo, com aplica??o de an?lise termogravim?trica, t?cnica de pir?lise t?rmica e catal?tica com nanomateriais, visando a produ??o de derivado de petr?leo. As borras extra?das em um equipamento soxhlet foram analisadas por an?lise elementar, cromatografia em camada fina, termogravimetria (TG) e pir?lise acoplado a um cromatogr?fico gasoso/espectro de massa (Py-GC/MS). Os catalisadores AlMCM-41 e AlSBA-15 foram sintetizados com uma raz?o molar de s?licio/alum?nio de 50 (Si/Al = 50), usando tetraetilortossilicato (TEOS) como fonte de sil?cio e pseudobuhemita (AlOOH) como a fonte de alum?nio. Os catalisadores indicam que os materiais apresentaram estrutura hexagonal, ?rea espec?fica de 783,6 m2/g para o AlMCM-41, 600 m2/g para o AlSBA-15.1 e 377 m2/g para o AlSBA-15.2). A BO extra?da apresentou de 65 a 95% de componentes org?nicos (?leo), de 5 a 35% de componentes inorg?nicos (sais e ?xidos) e diferentes composi??es dos derivados. Os catalisadores tipo AlSBA-15 apresentaram melhor desempenho na obten??o dos derivados de petr?leo, aumentando em 20% a produ??o de querosene e gas?leo leve. O potencial energ?tico da BO foi elevado, pois ela pode ser utilizada como combust?vel e processada com outras cargas pesadas do petr?leo para a produ??o de diferentes derivados de petr?leo
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Proposta de modelo de intera??o da Universidade Federal do Rio Grande do Norte e empresas do setor de petr?leo / Proposal of Interaction Model for Federal University of Rio Grande do Norte and Oil Industry

Perales, Wattson Jos? Saenz 27 January 2014 (has links)
Made available in DSpace on 2014-12-17T14:09:18Z (GMT). No. of bitstreams: 1 WattsonJSP_TESE.pdf: 3617145 bytes, checksum: ce1911e7afee8ff2e67129ff2e7a0a05 (MD5) Previous issue date: 2014-01-27 / Operational procedures may negatively interfere in negotiation and execution regarding universities and business companies. In some cases it may even derail business interaction. Thus, aiming to overcome this and other barriers a university-industry interaction model was structured. The model enhances the appropriation of technological solutions on behalf of enterprises, as well as aim to improve the quality of teaching and research done at the university. In order to conduct a case study, sampling considering the Federal University of Rio Grande do Norte (UFRN) was made as well as the Oil and Gas sector. For data collection questionnaires, classroom observation, document analysis, semi-structured interviews were used. The study describes the companies as well as the internal organization of UFRN in their interaction context. The diagnosis related to past interactions as well as the expectations of the companies and the university s internal subjects regarding the university-industry relationship were also studied. Thus, specific questionnaires were applied for the three types of groups: researchers, managers and business companies. These subjects pointed out that the great deal of barriers they identified were related to issues regarding the university internal management. Given these barriers, the critical factors were then identified in order to overcome this reality. Among the nine critical factors only one belongs to the macro environment, while the remaining factors are related to organizational issues present in the university context. It was possible to formulate a university-business interaction model one the researched focused on the case study results and contribution from a theoretical framework that was enabled trough literature review. The model considers all business collaboration mechanisms; it focuses on a particular strategic productive sector and provides a co-evolution vision over time, according to the sector?s development strategy. The need for institutionalizing the relationship with the companies involved is pointed out. The proposed model considers all the critical factors identified by the research; it aims long-term relationship with the company and integrates teaching, research and extension actions. The model implementation was also considered. It was seen that it must be done in three phases. The phases will be defined by the level of maturity in the relationship between the university and the companies. Thus, a framework was developed in order to assess the interaction level regarding company institutionalization. Whilst structuring the model was a concern with replication came up. It was pointed out that this model should not only serve to this specific case study situation. So the final result is a model of university-industry relationship appropriate in the first instance, for UFRN, but has applicability, in general, to any Brazilian university / Os procedimentos operacionais interferem negativamente na negocia??o e execu??o das intera??es universidade-empresa, em alguns casos inviabilizam a intera??o. Com o prop?sito de superar essa e outras barreiras foi estruturado um modelo de intera??o universidadeempresa que potencializa a apropria??o de solu??es tecnol?gicas por parte das empresas, assim como a melhoria na qualidade do ensino e da pesquisa na universidade. A partir de uma amostragem te?rica foi escolhida a Universidade Federal do Rio Grande do Norte (UFRN) e o setor de petr?leo do Rio Grande do Norte para conduzir um estudo de caso. Foram usados m?ltiplos m?todos de coleta de dados: question?rios, observa??o presencial, an?lise documental, entrevistas semiestruturadas. O estudo descreve as empresas do setor e a organiza??o interna da UFRN como o contexto no qual acontecem as intera??es. O diagn?stico das intera??es que j? aconteceram, assim como as expectativas das empresas e dos atores internos sobre a rela??o universidade-empresa foi elaborado aplicando question?rios espec?ficos para os tr?s grupos de atores: pesquisadores, gestores e empresas. A maioria das barreiras identificadas pelos atores da intera??o est? relacionada a quest?es de gest?o interna da universidade. Frente a essas barreiras foram identificados como fatores cr?ticos ?queles que contribuiriam para a supera??o das mesmas. Dentre os nove fatores cr?ticos para superar as barreiras encontradas somente um pertence ao macroambiente, enquanto os restantes s?o fatores organizacionais da universidade. Com foco nos resultados do estudo de caso e a contribui??o de um framework te?rico desenvolvido na pesquisa bibliogr?fica, foram formulados os pressupostos do modelo de intera??o universidadeempresa: considerar todos os mecanismos de colabora??o com as empresas, foco em um determinado setor produtivo estrat?gico, vis?o de coevolu??o ao longo do tempo de acordo com a estrat?gia de desenvolvimento do setor e necessidade de institucionaliza??o do relacionamento com as empresas. O modelo proposto abrange todos os fatores cr?ticos encontrados, busca o relacionamento de longo prazo com as empresas e integra as a??es de ensino, pesquisa e extens?o. Tamb?m foi discutido o processo de implanta??o do modelo, que dever? ser feito em tr?s fases, definidas em fun??o do n?vel de maturidade da universidade no relacionamento com as empresas. Para tanto, foi desenvolvido um quadro de refer?ncia para avaliar o n?vel de institucionaliza??o que a universidade atingiu na intera??o com empresas. Na estrutura??o do modelo houve uma preocupa??o com a replica??o, de forma que o mesmo n?o sirva somente ? situa??o espec?fica do estudo de caso realizado. Assim, o resultado final ? um modelo de relacionamento universidade-empresa adequado ? UFRN com o potencial de ser aplicado a qualquer universidade brasileira

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