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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.
311

The Norman Wells Project Coordinating Committee : an evaluation

Wilson, Jennifer Sharon 11 1900 (has links)
On July 31,1981 the federal cabinet approved the Norman Wells Pipeline and Expansion Project (NW Project). The project consisted of a tenfold expansion to the existing oilfield at Norman Wells, N.W.T., and the construction of an 870 km pipeline to Zama, Alberta. The approval was subject to a formal delay to allow "time for effective and meaningful planning" for the implementation of special management measures and benefit packages. Construction commenced January 1983 and the project became operational in April 1985. Although the project did not represent a major undertaking by industry standards, it was significant for the north because it was the first major hydrocarbon production and transportation project to be completed in the Northwest Territories. In addition, the project involved a number of unique impact management structures in order to coordinate government and industry's activities and incorporate native concerns. The approach, if successfully implemented, would represent an important step towards recognizing native concerns in project management. As a result of the new impact management structures, the NW Project has been referred to by the federal government and industry as a "model" for future northern development projects. On the other hand, native organizations viewed the project as a 'test case' that failed since all the conditions to their approval were not fully met. This inconsistency highlights the importance of clarifying which structures were successful for future northern megaprojects. This thesis focuses on one of the management structures unique to the NW Project, the Project Coordinating Committee (PCC). The PCC was established "to provide a forum for formal project update, reporting, communication and coordination of activities". The Committee had representatives from the federal government, the two proponents, the Government of the Northwest Territories, the Dene Nation, and the Metis Association. The specific purpose of this thesis is to assess the performance of the PCC using criteria derived from the literature on Planning Process and Citizen Participation, Group Dynamics, and Environmental Dispute Resolution. The results of this evaluation showed that the committee failed to satisfy all the performance criteria. However, at the root of the problem were the politics associated with the approval of the project, and in particular, the fact that the native land claims issue had not been resolved. Even in the absence of negotiated powers, the Dene and Metis had expected to actively participate in the regulation and management of the NW Project. When these powers were divorced from the processes the Dene and Metis were to be involved in, the Dene and Metis boycotted them. In addition to politics, there were also fundamental structural and operational deficiencies with the PCC which were detrimental to its performance. On the basis of this analysis, an improved committee framework for future projects is proposed.
312

Managing Exposure to Pipeline’s Risks: Improving Brazil’s Risk-Based Regulatory Process

Naime, Andre 21 June 2010 (has links)
Traditional risk-based decision-making processes have limitations that often compromise the management of technological hazards. The research is organized into three major components. Firstly, it investigates concepts and thinking outside the literature on risk regulation that offer opportunities to improve risk-based processes, such as governance and risk governance, environmental and social justice, vulnerability, resilience, complex systems, ethics, and the precautionary principle. Secondly, identified opportunities to improve risk-based approaches are assessed in the context of the Brazilian environmental licensing process for gas and oil transmission pipelines. The Brazilian case study is explored through interviews and surveys with thirty-two key stakeholders, aimed at describing and understanding the situation. Finally, it is discussed how the implications of the proposed conceptual framework and findings from the case study contribute to the theoretical perspectives on technological risk regulation. The research advocates that (1) regulatory processes for technological hazards need to effectively incorporate ‘human systems’ into their routines as a way to become more holistic; (2) decision-making processes need to strengthen the transition from assessment of risks to management of exposure; (3) regulators need to shift focus to the management of exposure as opposed to the current facility-centered management of risks; (4) this transition is facilitated if the regulatory process has an independent routine for management; and (5) a resilience plan, encompassing components from risk management and land-use planning, articulates the interaction between people and hazardous facilities, that share a common space, towards better practices to effectively manage exposure to risks. Considering these five points, the research suggests an adaptation of the Risk Governance Model for the regulation of hazardous linear installations.
313

Analysis of Parameters Affecting Costs of Horizontal Directional Drilling Projects in the United States for Municipal Infrastructure

January 2010 (has links)
abstract: Horizontal Directional Drilling (HDD) is a growing and expanding trenchless method utilized to install pipelines from 2 to 60 inch diameters for lengths over 10,000 foot. To date, there are not many public documents where direct costs and bid prices incurred by HDD installations are available and analyzed. The objective is to provide a better understanding of the factors affecting the bid prices of these projects. The first section of the thesis analyzes how project parameters such as product diameter, bore length and soil conditions affect the bid price of water and wastewater pipeline installations using HDD. Through multiple linear regressions, the effect of project parameters on bid prices of small, medium and large rigs projects is extracted. The results were further investigated to gain a better understanding of bid factors that influence the relationship between total cost and the project parameters. The second section uses unit cost, based on bid prices, to compare the costs incurred by defined categories. Parameters such as community type, product type, soil conditions, and geographical region were used in the analysis. Furthermore, using average unit cost from 2001 to 2009, HDD project cost trends are briefly analyzed against the main variations of the US economy from the same time horizon by using economic indicators. It was determined that project geometric factors influence more the bid price of small rig projects than large rig projects because external factors including market rates and economic situation have an increasing impact on bid prices when rig size increases. It was observed that bid price variation of HDD projects over years followed the same trend as the US economic variation described by economic indicators. / Dissertation/Thesis / M.S. Construction 2010
314

Centrifugal pump derating non-Newtonian slurries: analysis of the viscosity to be used in the hydraulic institute method

Kalombo, Jean-Jacques Ntambwe January 2013 (has links)
Thesis (MTech (Chemical Engineering))--Cape Peninsula University of Technology, 2013 / Centrifugal pumps are the most commonly used pumps in slurry transport systems. The design of pumping systems dealing with liquids more viscous than water requires a reliable method of pump performance prediction for the pump selection. For Newtonian fluids, the Hydraulic Institute method is well established, but there is no generally accepted method for non-Newtonian fluids. Many authors have fallen back on using the Hydraulic Institute method for non-Newtonian fluids. This requires a constant viscosity while non-Newtonian fluid viscosity varies with the shear rate. The question arises: What viscosity should be used in this method for non-Newtonian fluids? Two approaches have been developed: the use of a Bingham plastic viscosity made by Walker and Goulas (1984) and the use of the apparent viscosity calculated using an “equivalent hydraulic pipe” diameter, designed by Pullum et al. (2007). Previous results obtained from these two approaches are not in agreement. Therefore, the aim of this study is to explore a suitable procedure to determine a representative non-Newtonian viscosity to be used in the Hydraulic Institute method to predict the pump performance. To achieve this goal, a set of data was experimentally obtained and the existing data were reused. Test work was conducted using the pump test rig in the Flow Process Research Centre at the Cape Peninsula University of Technology. A Warman 4/3 pump was tested, using four concentrations of kaolin suspension and three concentrations of CMC solution. Five pump speeds were chosen to run these tests: 1200, 1400, 1600, 1800, and 2000 rpm. An additional data set obtained by testing two submersible centrifugal pumps with eight concentrations of sludge, in Stockholm, Sweden, was also analysed. These sets of data were analysed firstly according to the Walker and Goulas (1984) approach and secondly according to the Pullum et al. (2007) approach. The use of the apparent viscosity led to the better pump head prediction. The results of this prediction were close to those obtained in the Pullum et al. (2007) work, and even better in some cases. On the other hand, the use of the Bingham plastic viscosity showed better pump efficiency prediction, although the Walker and Goulas (1984) efficiency prediction range was achieved only for one pump out of five. The apparent viscosity reflected the non-Newtonian behaviour but it could not represent alone the non-Newtonian viscosity because of the poor efficiency predictions and the sensitivity of the Pullum et al. (2007) approach to a change in viscosity. From the results of this work, it is advisable that the pump performance prediction be done using both apparent and Bingham plastic viscosity, the apparent viscosity for the head prediction and the Bingham plastic viscosity for the efficiency prediction.
315

Avaliação do potencial de dados polarimétricos Radarsat-2 para mapeamento de uso e cobertura da terra em trecho de faixa de dutos sobre diferentes condições geomorfológicas /

Gomes, Alessandra Rodrigues. January 2011 (has links)
Orientador: Paulina Setti Riedel / Coorientador: Corina da Costa Freitas / Banca: Cenira Maria Lupinacci da Cunha / Banca: Gilberto José Garcia / Banca: Waldir Renato Paradella / Banca: Arnaldo de Queiroz da Silva / Resumo: Com a expansão das atividades de petróleo e gás, o transporte destes produtos precisa ser monitorado para permitir o abastecimento e preservar as paisagens sobre as quais o transporte é realizado e uma das formas mais recomendadas para o Brasil é através de dutos, devido à distância entre a produção e os centros de consumo. Para esta pesquisa foi selecionado um trecho na faixa de dutos Rio de Janeiro - Belo Horizonte para avaliar as potencialidades de dados Fine QuadPol do RADARSAT-2 no mapeamento do uso e cobertura da terra sobre diferentes condições geomorfológicas. A partir das matrizes de coerência e covariância dos dados Fine QuadPol foram realizadas análises da decomposição de alvos (Cloude-Pottier e Freeman-Durden) e classificadores de Wishart derivados destas decomposições. Para os dados em amplitude, foi utilizado o classificador MaxVer-ICM. Para todos os resultados também foi analisado o efeito da aplicação do filtro polarimétrico de Lee com janelas 5x5 e 7x7 pixels. Foram estabelecidas 11 classes de uso e cobertura da terra (nível 2) e realizada uma análise exploratória baseada nos dados em sigma zero e parâmetros resultantes das decomposições de Cloude-Pottier e Freeman-Durden (anisotropia, entropia, ângulo alfa, contribuições dos espalhamentos superficial, double-bounce e volumétrico). Como a separação das classes não foi possível para o nível 2, optou-se por manter o nível 1 onde são mapeadas somente as classes de cobertura da terra. Com base nos resultados alcançados pelos classificadores, pode-se dizer que o MaxVer-ICM apresentou o maior índice de concordância kappa (38%) enquanto o classificador de Cloude-Pottier teve o pior desempenho (19%). Os classificadores de Wishart obtiveram kappa de 27% para a Wishart derivada de Cloude-Pottier e 25% para... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Due to the expansion of the activities of oil and gas, the transportation of these products must be monitored to allow the supplies and preserve the landscapes on which transport is carried out and one of the most recommended forms of transport to Brazil is through pipelines due to distance of the consumers centers. For this research was selected a stretch in the Rio de Janeiro - Belo Horizonte pipelines to evaluate the potential of QuadPol Fine RADARSAT-2 data for mapping land use and land cover on different geomorphological conditions. From the covariance and coherence matrices of Fine QuadPol data was performed target decomposition (Cloude-Pottier and Freeman- Durden) and Wishart classifiers derived from these decompositions. For amplitude data, MaxVer-ICM was used as classifier. For all results was also analyzed the effect of applying Lee polarimetric filter with windows of 5x5 and 7x7 pixels. It was established 11 land use and land cover classes (level 2) and performed an exploratory analysis based on data from sigma nought and parameters resulting from the decomposition of Cloude and Pottier-Freeman-Durden (anisotropy, entropy, alpha angle, contributions from surface, double-bounce and volume scattering ). As the separation of classes was not possible to level 2, we chose to keep a level where they are mapped only the classes of land cover. Based on the results achieved by the classifiers, we can say that the ICMMaxVer had the highest rate of agreement kappa (38%) while the classifier Cloude- Pottier had the worst performance (19%). Wishart classifiers obtained kappa of 27% for the Wishart from Cloude-Pottier and 25% for the Wishart from Freeman-Durden. Based on the classifiers from the target decomposition and different parameters have presented results more visually... (Complete abstract click electronic access below) / Doutor
316

Programação das operações de transporte de derivados de petróleo em redes de dutos

Felizari, Luiz Carlos 2010 October 1914 (has links)
Este trabalho desenvolve uma estrutura de otimização que auxilia a tarefa de escalonamento das atividades de transporte de derivados de petróleo em uma rede de dutos. A malha dutoviária em estudo é utilizada para o transporte de derivados leves de petróleo com alto valor agregrado, sendo composta por 9 áreas (3 refinarias, 1 porto e 5 terminais). dentro deste cenário, a busca por resultados práticos considerando uma carga computacional aceitável torna-se um grande desafio. A abordagem adotada baseia-se na decomposição do problema, onde é investigada a aplicação de um modelo de programação linear inteira mista (Mixed Integer Linear Programming - MILP) com domínio de tempo contínuo para determinar o escalonamento das operações de curto-prazo da rede de dutos. Em função da abordagem hierárquica proposta, a etapa de ordenação da lista de bateladas utilizada na fase de temporização foi inicialmente desenvolvida através de heur´siticas construtivas que falham em situações particulares. Neste sentido, o problema de ordenação é reformulado através do emprego de estruturas de alto nível presentes em técnicas de programação lógica por restrições (Constraint Logic Programming - CLP). Na forma como é apresentada, a estrutura desenvolvida vem sendo extensivamente testada em cenários reais envolvendo mais de 100 bateladas para o horizonte de aproximadamente um mês. A partir desta ferramenta, novas programações de curto-prazo serão propostas, programações existentes serão validadas e informações de diagnóstico da rede serão obtidas de forma a auxiliar o processo de tomada de decisão operacional. / This work addresses an optimisation structure to support the operational decision-making of scheduling activities in a real world pipeline network. The used scenario to transport petroleum derivaties involves 9 areas (3 refineries, 1 harbour, and 5 distribution centres). Thus, the computational burden for determining a short-term scheduling within the considered scenario is a relevant issue. A decomposition approach is proposed to address such real-world problem. A continuous-time mixed integer linear programming model (MILP) is studied and used to determine the operational short-term scheduling. In this context of multilevel hierarchical structure, sequencing of activities are carried out by a heuristic algorithm which can fail for some particular cases. Thus, we propose to reformulate the sequencing problem by using high-level constructs of Constraint Logic Programming (CLP). The optimisation structure has been extensively tested in typical operational scenarios which, involve in general more than 100 batches. The scheduling horizon is considered to be about 1 month. Many insights have been derived from the obtained solutions, and the proposed approach can support the decision-making process.
317

Análise experimental do reinício do escoamento de petróleo parafínico em tubulações

Rosso, Nezia de 29 May 2014 (has links)
Durante as atividades de produção de petróleo offshore são utilizadas tubulações que transportam o petróleo bruto do fundo do poço até à plataforma ou até à costa marítima. No fundo mar as tubulações são submetidas a temperaturas da ordem de 4 oC. Nessas condições, quando a atividade de produção é interrompida para manutenções ou por paradas de emergência, o óleo bruto, com alto teor de parafinas, tende a se gelificar. Para reiniciar o escoamento são necessárias pressões acima da pressão usual de trabalho para promover a quebra do gel. A literatura mostra que não só o histórico de térmico, mas também o histórico de cisalhamento afetam a gelificação de óleos parafínicos e, portanto, a pressão de reinício do escoamento. O objetivo deste trabalho é avaliar experimentalmente as variáveis que influenciam o reinício do escoamento de petróleo parafínico. Para isso, uma unidade experimental foi construída de modo a reproduzir experimentalmente o reinício do escoamento de petróleo parafínico gelificado. A unidade permite o controle da temperatura, da taxa de resfriamento, da taxa de cisalhamento e do tempo de repouso na formação do gel. A pressão máxima necessária para o início do escoamento foi observada, os valores coletado e analisado. A investigação realizada mostra que todos os parâmetros testados apresentam alguma influência na pressão durante o reinício do escoamento de óleo parafínicos gelificados. / In offshore production, pipelines are used to transport crude oil from the well bore to the platform and from the plataform to the seacoast. When production is interrupted for maintenance or emergency, waxy crude oils tend to form gel at seabed low temperatures. At flow start-up, an increase in pressure above the usual operating pressure is required to break the gel. The literature has reported that not only the temperature but also the cooling rate, the shear rate during cooling and the material aging time affect the gelation of waxy crude oils, and, therefore, the start-up pressure. The objective of the current work is to evaluate experimentally the start-up flow of waxy crude oils in pipelines. In order to accomplish that, an experimental lab loop was build to reproduce the flow start-up of gelled waxy crude oils. The loop allows the control of temperature, cooling rate, shear rate and aging time in the gel formation. The pressure peaks measured during the flow restart were presented and analized as a function of the controlled parameters. The research shows that all parameters tested have some influence on the picks of pressure during the start up flow of paraffinic oil gelled.
318

Programação das operações de transporte de derivados de petróleo em redes de dutos

Felizari, Luiz Carlos 2010 October 1914 (has links)
Este trabalho desenvolve uma estrutura de otimização que auxilia a tarefa de escalonamento das atividades de transporte de derivados de petróleo em uma rede de dutos. A malha dutoviária em estudo é utilizada para o transporte de derivados leves de petróleo com alto valor agregrado, sendo composta por 9 áreas (3 refinarias, 1 porto e 5 terminais). dentro deste cenário, a busca por resultados práticos considerando uma carga computacional aceitável torna-se um grande desafio. A abordagem adotada baseia-se na decomposição do problema, onde é investigada a aplicação de um modelo de programação linear inteira mista (Mixed Integer Linear Programming - MILP) com domínio de tempo contínuo para determinar o escalonamento das operações de curto-prazo da rede de dutos. Em função da abordagem hierárquica proposta, a etapa de ordenação da lista de bateladas utilizada na fase de temporização foi inicialmente desenvolvida através de heur´siticas construtivas que falham em situações particulares. Neste sentido, o problema de ordenação é reformulado através do emprego de estruturas de alto nível presentes em técnicas de programação lógica por restrições (Constraint Logic Programming - CLP). Na forma como é apresentada, a estrutura desenvolvida vem sendo extensivamente testada em cenários reais envolvendo mais de 100 bateladas para o horizonte de aproximadamente um mês. A partir desta ferramenta, novas programações de curto-prazo serão propostas, programações existentes serão validadas e informações de diagnóstico da rede serão obtidas de forma a auxiliar o processo de tomada de decisão operacional. / This work addresses an optimisation structure to support the operational decision-making of scheduling activities in a real world pipeline network. The used scenario to transport petroleum derivaties involves 9 areas (3 refineries, 1 harbour, and 5 distribution centres). Thus, the computational burden for determining a short-term scheduling within the considered scenario is a relevant issue. A decomposition approach is proposed to address such real-world problem. A continuous-time mixed integer linear programming model (MILP) is studied and used to determine the operational short-term scheduling. In this context of multilevel hierarchical structure, sequencing of activities are carried out by a heuristic algorithm which can fail for some particular cases. Thus, we propose to reformulate the sequencing problem by using high-level constructs of Constraint Logic Programming (CLP). The optimisation structure has been extensively tested in typical operational scenarios which, involve in general more than 100 batches. The scheduling horizon is considered to be about 1 month. Many insights have been derived from the obtained solutions, and the proposed approach can support the decision-making process.
319

Desenvolvimento de procedimentos para avaliação de curvas J-R em espécimes à fratura SE(T) utilizando o método de flexibilidade. / Estimation procedure of J-R Curves for SE(T) fracture specimens based upon the unloading compliance methodology.

Sebastian Cravero 26 November 2007 (has links)
Este trabalho apresenta o desenvolvimento de procedimentos para a medição de curvas de resistência J-R em espécimes SE(T) usando os métodos de flexibilidade elástica e método n. Uma descrição da metodologia sobre a qual J e o crescimento de trinca são medidos estabelece o contexto para determinar dados de resistência ao rasgamento dúctil com o emprego de curvas carga vs. deslocamento obtidas experimentalmente. A extensiva matriz de análises em estado plano de deformações de espécimes SE(T) complementada, em algumas geometrias selecionadas, com análises 3D permite a determinação numérica da flexibilidade adimensional, u, e fatores nJ e Y para uma grande faixa de proporções geométricas e propriedades de material características de aços estruturais e para dutos. Ensaios laboratoriais de um aço API 5L X60 à temperatura ambiente usando espécimes SE(T) carregados por pinos com entalhes laterais (side-grooves) fornecem os dados de carga e deslocamento necessários para validar o procedimento para determinar curvas de resistência do material. Os resultados apresentados nesta tese fornecem uma base de soluções para o futuro estabelecimento de norma padronizada para a medição experimental de curvas J-R em corpos de prova SE(T) mecanicamente similares a dutos com defeitos bidimensionais. / This work provides an estimation procedure to determine J-resistance curves for pinloaded and clamped SE(T) fracture specimens using the unloading compliance technique and the n-method. A summary of the methodology upon which J and crack extension are derived sets the necessary framework to determine crack resistance data from the measured load vs. displacement curves. The extensive plane-strain analyses and key 3D results enable numerical estimates of the nondimensional compliance, u , and parameters n and Y for a wide range of specimen geometries and material properties characteristic of structural and pipeline steels. Laboratory testings of an API 5L X60 steel at room temperature using pin-loaded SE(T) specimens with side-grooves provide the load-displacement data needed to validate the estimation procedure for measuring the crack growth resistance curve for the material. The results presented in the this thesis produce a representative set of solutions which lend further support to develop standard test procedures for constraint-designed SE(T) specimens applicable in measurements of crack growth resistance for pipelines.
320

Estudo experimental do escoamento agua-oleo com precipitação de parafinas em dutos submarinos / Experimental study of the oil-water flow with paraffin precipitation in submarine

Oliveira, Rafael de Castro 14 August 2018 (has links)
Orientador: Sergio Nascimento Bordalo / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica / Made available in DSpace on 2018-08-14T18:41:08Z (GMT). No. of bitstreams: 1 Oliveira_RafaeldeCastro_M.pdf: 1603033 bytes, checksum: 5b19ae643a703f87aab5fd52d37d741a (MD5) Previous issue date: 2005 / Resumo: A deposição de parafinas em dutos submarinos é um sério problema para a produção marítima de petróleo. Parafinas são substâncias orgânicas caracterizadas por longas cadeias de carbono e hidrogênio, formadas por ligações covalentes simples, apresentando peso molecular elevado, devido ao grande número de átomos de carbono. Parafinas precipitam-se de soluções oleosas devido a um decréscimo de temperatura, e com o tempo, a parafina sólida fora da solução líquida deposita-se nas paredes das tubulações obstruindo o fluxo e ocasionando o aumento de perda de carga por fricção nas linhas. Em conseqüência, ocorre diminuição da vazão dos fluidos e entupimento da seção do duto de produção, entre outros problemas. O presente trabalho visa estudar esse fenômeno na produção de petróleo no mar, onde existe um gradiente térmico ao longo do escoamento devido à elevada diferença de temperatura entre o reservatório e o fundo do oceano. Para esse fim, foi construído um aparato experimental que consiste em uma tubulação horizontal de 25,4 mm (1") de diâmetro e cerca de 13 metros de comprimento, imersa em um banho de água gelada. Medidas de gradiente de pressão e de temperatura são efetuadas ao longo da tubulação, de modo a estudar o efeito da presença de água no escoamento, em relação ao fluxo monofásico de óleo, na deposição de parafina e no aumento do gradiente de pressão. / Abstract: The paraffin deposition in submarine pipelines poses a serious problem for the offshore oil production. Paraffins are organic substances characterized by long chains of carbon and hydrogen, linked by simple covalent bonds, presenting high molecular weight, due to the large number of carbon atoms. Paraffins precipitate off oily solutions due to a temperature decrease, and with time, the solid paraffin out of the liquid solution deposits on the walls of the pipeline, obstructing the flow and causing an increase of the pressure drop along the lines. Consequently, a reduction of the flow rate occurs, as well as clogging of the cross section of the production duct, among others problems. The present work aims to study this phenomenon in the case of oil production at the sea, where a thermal gradient exists along the flowlines, due to high temperature difference between the petroleum reservoir and the bottom of the ocean. To this end, an experimental apparatus was built consisting of an horizontal pipeline about 13 meters long with a 25,4 mm (1 in) diameter, immersed in a chilly water bath. Measurements of temperature and pressure were taken along the length of the pipeline, to study the effect of the two-phase flow, in relation to the single-phase flow, on the paraffin deposition and on the increase of the pressure gradient. / Mestrado / Explotação / Mestre em Ciências e Engenharia de Petróleo

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