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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.
331

[en] PERFORMANCE VERIFICATION METHODOLOGY OF MULTIPHASE FLOW METERS IN ALLOCATION MEASUREMENT IN THE OIL AND GAS INDUSTRY / [pt] METODOLOGIA DE VERIFICAÇÃO DE DESEMPENHO DE MEDIDORES DE VAZÃO DE FLUIDO MULTIFÁSICO NA MEDIÇÃO PARA APROPRIAÇÃO NA INDÚSTRIA DE ÓLEO E GÁS NATURAL

LUIZ OCTAVIO VIEIRA PEREIRA 20 February 2019 (has links)
[pt] O medidor de vazão de fluido multifásico (MM) se desenvolveu impulsionado principalmente pela necessidade da indústria de óleo e gás em medir a vazão da produção dos poços que comumente é composta por petróleo, gás e água. Em outubro de 2015, a Agência Nacional de Petróleo, Gás Natural e Biocombustíveis (ANP) publicou o Regulamento Técnico de Medição de Fluido Multifásico para Apropriação de Petróleo, Gás Natural e Água que apresenta os requisitos através de planos que as empresas operadoras de óleo e gás precisam preparar e submeter para obter a autorização para aplicar o MM na medição para apropriação. Contudo, esse regulamento não especifica a metodologia que deve ser utilizada no denominado plano de verificação de desempenho para avaliar desempenho do MM no campo, cabendo a cada operadora desenvolver a sua metodologia para esse fim e apresentar a ANP. Este trabalho propõe e aplica uma metodologia para verificação de desempenho para MM com resultados de testes realizados em laboratório com fluidos reais e em campo de produção de petróleo e gás. É observado que testes com tempo curto de duração, inferior a 1000 segundos, tendem a gerar incertezas mais elevadas do que testes com longa duração, com mais de 1000 segundos, como os realizados na plataforma. Sendo assim, os resultados de incerteza de medição maiores gerados no laboratório com tempos de integração curtos podem ser considerados mais conservativos que os resultados dos testes realizados na plataforma. / [en] The multiphase flowrate (MM) was driven by the necessity of the oil and gas industry to measure the production flow of the wells that are commonly composed of oil, gas and water. In October 2015, the National Agency for Petroleum, Natural Gas and Biofuels (ANP) published the Technical Regulation for Measurement of Multiphase Fluid for Petroleum, Natural Gas and Water produced, which presents the requirements through plans that oil and gas companies need to prepare and submit for authorization to apply the MM in the measurement for allocation. However, this regulation does not specify the methodology that should be used in the so-called performance verification plan to evaluate the performance of the MM in the field, it being incumbent on each operator to develop its methodology for this purpose and present the ANP. This work proposes and applies a methodology for performance verification for MM with test results performed in the laboratory with real fluids and in oil and gas field. It was observed that short duration tests, below 1000 seconds, tend to generate higher uncertainties than long tests, higher than 1000 seconds, such as those performed on the platform. Thus, the higher measurement uncertainty results generated in the laboratory with short integration times can be considered more conservative than the results of the tests performed in the platform.
332

Dimensionnement de canalisations sur des critères en déformation dans des environnements extrêmes / Strain-based design of pipelines in extreme environments

Soret, Clément 21 April 2017 (has links)
Les standards consacrés à la conception des oléoducs se concentrent principalement sur les chargements opérationnels, tels que les pressions internes et externes, et les procédures d'analyse de défauts actuelles n'exploitent pas les capacités d'écrouissage du matériau. Pourtant, dans des conditions extrêmes, les oléoducs peuvent être soumis à des contraintes au-delà de la limite d'élasticité jusqu'à atteindre 2.5% de déformations plastiques. Ici, les procédures proposées par ExxonMobil et PRCI basées sur des critères en déformation sont présentées, et l'utilisation de l'éprouvette SENT (Single Edge Notched Tension) pour caractériser la ténacité est étudiée, en comparant les différentes procédures d'essais recommandées. Puis, une importante campagne expérimentale a été réalisée pour caractériser deux aciers pour oléoducs à température ambiante et à basses températures. Les comportements mécaniques des matériaux de base et d'apport ont été identifiés grâce à l'utilisation de l'analyse inverse, et il est montré que le modèle d'endommagement GTN permet de modéliser finement les essais sur éprouvettes de laboratoire. Enfin, deux essais sur structures (pression et flexion, puis pression et traction) ont été réalisés de manière à comparer les approches globales et le modèle d'endommagement GTN. Ce dernier démontre une bonne transférabilité de l'éprouvette vers la structure. / Pipeline design codes and standards traditionally focus on the operational loadings such as internal and external pressures that are likely to exist over the entire lifetime of the pipeline. Existing Engineering Critical Assessments are mostly based on stress considerations, where the design margin is given as a percentage of the yield strength. In extrem environments, pipelines may experience stresses beyond the yield and plastic deformations up to 2.5 %. In such conditions, strain-based design procedures apply. In this work, a literature review of the existing strain based methods is proposed, including ExxonMobil and PRCI multi-tier approaches. The use of the Single Edge Notched Tension (SENT) specimen to measure the material toughness is then studied, benchmarking the recommended testing procedures from literature. A comprehensive experimental campaign was carried out to fully characterize two actual line pipes at room and low temperatures. The mechanical behavior of parent and weld materials are identified using an inverse analysis, and GTN damage model is shown to allow accurate modeling of the laboratory testings. Finally, two full scale tests (pressure + bending or pressure + tension) were carried out to benchmark the global approaches and GTN damage model. The latter showed a very good transferability from specimens to the structure.
333

Integration and Simulation of a Bitumen Upgrading Facility and an IGCC Process with Carbon Capture

El Gemayel, Gemayel 19 September 2012 (has links)
Hydrocracking and hydrotreating are bitumen upgrading technologies designed to enhance fuel quality by decreasing its density, viscosity, boiling point and heteroatom content via hydrogen addition. The aim of this thesis is to model and simulate an upgrading and integrated gasification combined cycle then to evaluate the feasibility of integrating slurry hydrocracking, trickle-bed hydrotreating and residue gasification using the Aspen HYSYS® simulation software. The close-coupling of the bitumen upgrading facilities with gasification should lead to a hydrogen, steam and power self-sufficient upgrading facility with CO2 capture. Hydrocracker residue is first withdrawn from a 100,000 BPD Athabasca bitumen upgrading facility, characterized via ultimate analysis and then fed to a gasification unit where it produces hydrogen that is partially recycled to the hydrocracker and hydrotreaters and partially burned for power production in a high hydrogen combined cycle unit. The integrated design is simulated for a base case of 90% carbon capture utilizing a monoethanolamine (MEA) solvent, and compared to 65% and no carbon capture scenarios. The hydrogen production of the gasification process is evaluated in terms of hydrocracker residue and auxiliary petroleum coke feeds. The power production is determined for various carbon capture cases and for an optimal hydrocracking operation. Hence, the feasibility of the integration of the upgrading process and the IGCC resides in meeting the hydrogen demand of the upgrading facility while producing enough steam and electricity for a power and energy self-sufficient operation, regardless of the extent of carbon capture.
334

Finansmarknadens reaktioner på naturkatastrofer förorsakade av enskilda bolag : En eventstudie av katastrofen i den Mexikanska golfen 2010

Moya, Juan, Östlund, Johannes January 2010 (has links)
Bakgrund: Den 20:e april 2010 inträffade en explosion på BP:s oljeplattform Deepwater Horizon i Mexikanska Golfen. Explosionen uppstod på grund av metangas som under högt tryck expanderade på plattformen och sedan antändes. Detta ledde senare till att oljeplattformen sjönk och ett stort okontrollerat oljeläckage uppstod på cirka 1500 meters djup.          Att explosionen i den mexikanska golfen har påverkat BP negativt och varit mycket kostsamt för företaget är uppenbart, börskursen hade som mest sjunkit med cirka 60 procent. Det kan vara intressant att undersöka huruvida denna katastrof, utlöst av en enskild aktör, också har spridit sig över till andra aktörer i Olja & Gas sektorn. Syfte: Syftet med denna C-uppsats är att undersöka huruvida BP:s katastrof i den Mexikanska golfen har påverkat andra aktörer i samma sektor (Olja & Gas sektorn). Metod: Sekundärdata presenteras som en kvantitativ ansats i form av siffror och för att kunna dra slutsatserna använder vi oss av en deduktiv ansats.I denna studie tillämpas en metodikteknik i form av en eventstudie, där beräkningar av den abnorma och förväntade avkastningen baseras på marknadsmodellen. Vidare har två hypoteser testats, där syftet med Hypotes I är att pröva huruvida information om händelsen i den Mexikanska Golfen påverkar andra företag i samma sektor som BP. Syftet med Hypotes II är att testa samma företag under samma period som Hypotes I, men undersöker förändring i tradingvolymerna istället för i aktiekurserna. Teori: Effektiva Marknadshypotesen, Random Walk och Flockbeteende Slutsatser: Dessa båda undersökningar d.v.s. Hypotes I och Hypotes II pekar starkt på slutsatsen att eventet har haft inverkat på övriga bolag i sektorn. Vi kunde vid en jämförelse med tidigare studier som genomförts på andra katastrofer, konstatera att skeendet har både likheter och skillnader. / Background: On the 20th April 2010, the BP oil platform Deepwater Horizon, situated in the Mexican Gulf, exploded. The explosion was caused by methanol gas that, under high pressure expanded and thereafter ignited. The platform submerged and caused a severe and uncontrollable oil leakage at 1500 meters depth.It is obvious that the explosion in the Mexican Gulf has impacted BP in a negative manner and cause BP large financial loss, the company shares had at its worst point depreciated by 60 percent. It may be of interest to investigate whether this catastrophe, caused by one independent party, also have affected other companies within the Oil and Gas industry. Purpose: The aim of this assignment is to investigate whether BP’s catastrophe in the Mexican Gulf has affected other companies within the same industry. (Oil and Gas) Methodology: Secondary data is presented as a quantitative approach in the shape of values and we use a deductive approach in order to draw the conclusions.The methodology used in this study is event study, in which calculation of the abnormal and expected revenue are based on the market model. We will test two types of hypothesis, where the aim of Hypothesis I is to test in which way information about the event in the Mexican Gulf affects other companies in the same industry as BP. The aim of Hypothesis II is to test the same companies during the same period as Hypothesis I, but with a focus on analyzing trading volume instead of the stock market value. Theory: Efficient Market Hypothesis, Random Walk and Herd Behavior Conclusion: Both investigations, i.e. Hypothesis I and Hypothesis II indicate that the event has had an impact on other companies in the same industry. We could, in a comparative analysis with earlier studies, based on other catastrophes, conclude that the event demonstrates similarities as well as differences.
335

南海油氣共同開發之模式:對中華民國政策之啟示 / South China Sea oil and gas joint development model: Enlightenment from the Policy of the Republic of China

陳子豪, Chen, Tzu Hao Unknown Date (has links)
從1982年之《國際海洋法公約》規定相關國家在爭議之海域劃界達成協議之前,有權利就爭議海域的管理和開發做出臨時性的安排。而共同開發正是作為一種解決海域劃界爭端而被廣泛採用的臨時性辦法,共同開發方案一經提出便得到了國際實踐的認同。 通過國際實踐案例的分析,並從中汲取國際共同開發成功案例中的經驗和啟示,總結出國際共同開發的管理模式及其特點並促進我國參與南海油氣共同開發,強化與周邊國家區域利益協調和合作局勢,積極推動共同開發合作建立,避免南海周邊國家避開我國簽訂雙邊或多邊協議去侵占我國南海油氣資源及海域主權,並就我國南海管轄權範圍內積極進行合作以維護我國在南海的海洋權利。 / 1982’s International Law of the sea has prescribed that the related countries are liable to make every effort to make an interim arrangement upon the management and utilization of maritime space after coming an agreement on maritime delimitation. Joint development that is the interim arrangement with broad adoption on solving the dispute of maritime delimitation, which now has been acknowledged in international practices. Through analyzing the international cases, and the ultimate goal of this paper is that R.O.C will learn the experience and inspiration from the successful international joint development model, effectively accelerate the joint development of oil and gas, strengthen the coordination and cooperation of regional benefit with surrounding countries, and actively promote the joint development and cooperation to establish, to avoid the neighboring countries of the South China Sea to avoid bilateral or multilateral agreements signed to occupy Republic of China's oil and gas resources and sea sovereignty, and within the jurisdiction of China's South China Sea within the active cooperation to safeguard Republic of China's maritime rights in the South China Sea.
336

Integration and Simulation of a Bitumen Upgrading Facility and an IGCC Process with Carbon Capture

El Gemayel, Gemayel January 2012 (has links)
Hydrocracking and hydrotreating are bitumen upgrading technologies designed to enhance fuel quality by decreasing its density, viscosity, boiling point and heteroatom content via hydrogen addition. The aim of this thesis is to model and simulate an upgrading and integrated gasification combined cycle then to evaluate the feasibility of integrating slurry hydrocracking, trickle-bed hydrotreating and residue gasification using the Aspen HYSYS® simulation software. The close-coupling of the bitumen upgrading facilities with gasification should lead to a hydrogen, steam and power self-sufficient upgrading facility with CO2 capture. Hydrocracker residue is first withdrawn from a 100,000 BPD Athabasca bitumen upgrading facility, characterized via ultimate analysis and then fed to a gasification unit where it produces hydrogen that is partially recycled to the hydrocracker and hydrotreaters and partially burned for power production in a high hydrogen combined cycle unit. The integrated design is simulated for a base case of 90% carbon capture utilizing a monoethanolamine (MEA) solvent, and compared to 65% and no carbon capture scenarios. The hydrogen production of the gasification process is evaluated in terms of hydrocracker residue and auxiliary petroleum coke feeds. The power production is determined for various carbon capture cases and for an optimal hydrocracking operation. Hence, the feasibility of the integration of the upgrading process and the IGCC resides in meeting the hydrogen demand of the upgrading facility while producing enough steam and electricity for a power and energy self-sufficient operation, regardless of the extent of carbon capture.
337

Regulation and Political Costs in the Oil and Gas Industry: An Investigation of Discretion in Reporting Earnings and Oil and Gas Reserves Estimates

Kurdi, Ammr 08 1900 (has links)
This study investigates the use of discretion by oil and gas companies in reporting financial performance and oil and gas reserve estimates during times of high political scrutiny resulting from increases in energy prices. Hypotheses tested in prior literature state that companies facing the risk of increasing taxes or new regulations reduce reported earnings to reduce this risk. This study uses a measure of high profitability (rank order of return on assets relative to industry peers) to identify oil and gas companies more likely to manage earnings during the period from 2002 to 2008. Two measures of discretionary accruals (total and current discretionary accruals), and a measure of discretionary depreciation, depletion, and amortization (DDA) were used as indicators of discretion exercised in reporting earnings. Data on oil and gas reserve disclosures was also hand-collected from Forms 10-K to investigate whether managers use reserve estimate revisions to reduce reported earnings through increasing the annual depletion expense. Results suggest that both oil and gas refining and producing firms use negative discretionary accruals to reduce reported earnings. Results also indicate that profitability is an important determinant of the use of negative discretionary accruals by these companies regardless of the time period examined. There is also evidence that oil and gas producing firms opportunistically revise their oil and gas reserve estimates to increase depreciation, depletion, and amortization expense during periods of high oil prices.
338

Thawing the tension: U.S.-Greenland relations and climate change (non)securitization

Crowther, Joe Edward 27 January 2022 (has links)
U.S. Arctic foreign policy and the U.S. influence on Greenland has been studied predominantly regarding U.S. military and defence concerns. However, during the Trump Administration, the U.S. Arctic foreign policy agenda significantly shifted, placing Greenland as an integral component of the 2017-2021 Republican administration’s Arctic geopolitical aspirations, and not only for defence purposes. I argue that U.S-Greenland relations were significantly impacted when President Trump offered to purchase Greenland from the Kingdom of Denmark in the summer of 2019. Following the offer, Greenland emerged as a focal point of the Trump Administration’s geopolitical and economic security interests in the Arctic. Consequently, Greenland finds itself at the centre of a complex Arctic arena, with vastly larger and more powerful states taking an interest in Greenland’s economic potential due to its natural resources. Nevertheless, Trump’s offer was highly problematic as Greenland is an Inuit nation with the political goal to become independent from their colonial ties with Denmark. Despite the offer causing initial outrage, U.S.-Greenland collaborative relations have only developed since. I analyze why this has occurred, conveying that the similar approaches of Trump and Greenland towards climate change created the possibility for the strengthening of U.S.-Greenland bilateral relations. Climate change threatens the Arctic, yet the melting ice also provides more accessibility to rich natural resources. Climate change therefore presents not only threats, but opportunities. Greenland has a right and desire to pursue economic development for a financially viable independence through utilizing carboniferous, extractive industries. The U.S. has also sought to utilize the economic opportunity that Arctic climate change presents but with different motives. The U.S. and Greenland have subsequently become interlinked in a complex Arctic constellation of foreign policy and economic opportunity. Regardless of changing approaches to climate change, the Trump Administration has significantly impacted the future of U.S.-Greenland relations and Greenland’s political future. / Graduate
339

[en] A FRAMEWORK TO SUPPORT BIDDING STRATEGIES IN OIL AND GAS E&P AUCTIONS BASED ON RISK AVERSION METRICS / [pt] UM FRAMEWORK PARA SUPORTE À ESTRATÉGIAS DE OFERTA EM LEILÃO DE E&P DE PETRÓLEO E GÁS BASEADO EM MÉTRICAS DE AVERSÃO À RISCO

FERNANDA SILVA NUCCI 11 January 2023 (has links)
[pt] Em muitos países, uma área de Exploração e Produção de petróleo é adquirida através de um leilão. Embora o processo de liquidação do leilão seja tipicamente simples, sob a ótica do tomador de decisão a identificação da melhor oferta é complexa. Para sua valoração, deve ser pré-definido o modelo de desenvolvimento com diversas alternativas associadas, alto grau de incertezas técnicas, de mercado e operacionais, e submetido a uma determinada condição fiscal. A decisão por uma determinada alternativa gera impactos e investimentos elevados para a empresa. O trabalho proposto visa a construção de um framework para dar suporte ao processo de escolha da melhor oferta que maximize uma medida de valor para a empresa, auxiliando o tomador de decisão e considerando as incertezas envolvidas no processo. Foram utilizados os indicadores de performance apresentados na literatura: Valor Presente Líquido (VPL), Conditional Value-at-Risk, Omega e Exposição Financeira. Afim de melhor quantificar risco/benefício financeiro no processo de tomada de decisão foram construídas medidas de risco: Mean-Weighted CVaR, Mean-Weighted Double-Sided CVaR, Beta e Negative-Positive cashflow ratio. Para ilustrar a aplicabilidade do framework proposto, um experimento numérico baseado em um caso hipotético é apresentado. Em decorrência deste experimento, foi identificado que alterações na configuração da produção alteram significativamente os resultados dos indicadores. Além disso, a partir de uma ponderação entre probabilidade de ganho e o resultado do indicador Mean-Weighted CVaR, foi identificada a melhor oferta para a área, dada a condição fiscal do leilão. / [en] In many countries, an oil and gas area of Exploration and Production is acquired through an auction. Although the auction settlement process is typically simple, from the decision maker s point of view, identifying the best offer is complex. For its valuation, the development model must be pre-defined with several associated alternatives, a high degree of technical, market and operational uncertainties, and submitted to a fiscal term. The decision for a particular alternative generates high impacts and investments for the company. The proposed work aims to build a framework to support the process of choosing the best offer that maximizes a measure of value for the company, helping the decision maker and considering the uncertainties involved in the process. The performance indicators presented in the literature were used: Net Present Value (NPV), Conditional Value-at-Risk, Omega and Financial Exposure. In order to better quantify financial risk/benefit in the decisionmaking process, risk measures were constructed: Mean-Weighted CVaR, Mean- Weighted Double-Sided CVaR, Beta and Negative-Positive cashflow ratio. To illustrate the applicability of the proposed framework, a numerical experiment based on a hypothetical case is presented. As a result of this experiment, it was identified that changes in the configuration of production significantly alter the results of the indicators. In addition, from a weighting between the probability of gain and the result of the Mean-Weighted CVaR measure, the best offer for the area was identified, given the fiscal term of the bid.
340

Transitioning Central Appalachia: Understanding Framework Conditions Supporting the Adaptation to New Energy Economies

Jonathan, Norris Allen 11 July 2018 (has links)
No description available.

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