Since the 1980’s horizontal drilling has been a game-changing technology as it allowed the oil and gas industry to produce from reservoirs previously considered marginal or uneconomic. However, while it is considered a mature technology, directional drilling is still done in a reactive fashion. Although many directional drillers are quite adept at predicting the directional response of the bottomhole assembly (BHA) in a given well, the ability to manage all of the drilling parameters on a foot by foot basis while accurately predicting the effects of each parameter is impossible for the human brain alone. Given current rig rates, any amount of increased slide time and its reduced ROP which occurred due to poorly predicted directional response can result in a significant economic impact. There exist many measured parameters or system inputs which have been proven to affect the directional response of a drilling system. One parameter whose effect has not been investigated is mechanical specific energy or MSE. MSE is measure of how efficient the drilling process is in relation to rate of penetration. To date, MSE has primarily been used with for vibration analysis and rate of penetration optimization. The following dissertation covers research into the effect of MSE on the overall wellbore direction change or dog-leg severity. Using published experimental data, a correlation was developed which shows a clear relationship between the dog-leg severity, rate of penetration (ROP) and MSE. The correlation requires only a few hundred feet of drilling before it is able to be tuned to match an individual well’s results. With minimal tuning throughout the drilling of a well, very good results can be obtained with regards to forecasting dog-leg severity as the wellbores were drilled ahead. The correlation was tested using data from multiple, geo-steered wells drilled in a shale reservoir. The analysis of the correlation using real-world data proved it to be a robust and accurate method of predicting the magnitude of dog-leg severity. The use of this correlation results in a smoother wellbore, drilled with a faster overall ROP with a better chance of staying within the geologic targets.

Orientador: Alexandre Campane Vidal / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica e Instituto de Geociências / Made available in DSpace on 2018-08-25T17:39:31Z (GMT). No. of bitstreams: 1 CorreaNeto_Darcy_M.pdf: 10780036 bytes, checksum: a9e1aeacd891517e00b449caddbeb578 (MD5) Previous issue date: 2014 / Resumo: A exposição de um poço horizontal à formações geológicas perfuradas ocorre de forma diferente a exposição de um poço vertical à mesma formação. O poço horizontal atravessa as camadas geológicas de forma sub-paralelas, expondo estas camadas com uma extensão maior do que os poços verticais, que as atravessam de forma sub-perpendicular, formando exposições abruptas. Essa diferença de exposição afeta os perfis volumétricos, os perfis que compõe uma média dos 360º do poço, considerando um corte perpendicular a direção longitudinal do poço de forma diferente em relação aos perfis azimutais. Devido a esta diferença na exposição, é importante considerar métodos diferentes para a estimativa de Net Pay entre poços verticais e horizontais. Assim sendo, o objetivo deste trabalho foi o de utilizar perfis de densidade azimutais para diferenciar as estimativas de Net Pay. Para a consecução dos objetivos deste trabalho, foram feitos dois estudos. O primeiro deles consiste na utilização de perfis azimutais de densidade para gerar diferentes cálculos do Net Pay. Um segundo estudo compreendeu a análise de diferentes algoritmos de aumento de contraste de imagem, para auxiliar na identificação das feições geológicas, auxiliando na análise de Net Pay. Os perfis utilizados para a realização deste trabalho são de um poço produtor de óleo perfurado em um turbidito da costa leste brasileira. Neste poço, foi possível identificar algumas feições geológicas, como arenitos e folhelhos (camadas), cimentação carbonática e falha geológica. Como resultado do cálculo de Net Pay dos diferentes perfis de densidade analisados neste trabalho, foi possível identificar uma diferença de até 10,72% de Net Pay no mesmo poço. O Net Pay final das curvas de densidade volumétrica, densidade up, densidade down, conjunto da densidade up ou down e imagem obtiveram os seguintes resultados respectivamente: 88,42%, 91,44%, 89,86%, 96,62% e 99,14%. Quanto aos algoritmos de aumento de contraste, foram aplicados 14 algoritmos do domínio do espaço, possibilitando uma melhor visualização de contatos geológicos, falhas e camadas geológicas. Entre todos os algoritmos utilizados, os que apresentaram melhores resultados em imagem de densidade foram os algoritmos de derivada de 2ª ordem, corte dos níveis de cinza e histograma normalizado. Conclui-se portanto, que cada feição geológica encontrada ao longo do poço afeta os perfis azimutais e a imagem de densidade de forma diferente, portanto, a utilização dos diferentes perfis e dos algoritmos de aumento de contraste de imagem podem deflagar quais curvas de densidade devem ser utilizadas em determinadas profundidades do poço para obter o Net Pay mais preciso / Abstract: Drilled geological formation exposure are different considering horizontal and vertical wells. A horizontal well passes throught geological beds almost parallel, resulting in a wider exposure of the formation along the well path, while vertical wells passes through the same formation perpendicularly, resulting in abrupt contact between beds. This difference in exposure affects the volumetric well logs, logs that are composed by the average of the 360º of the well, considering a perpendicular cut of the longitudinal direction of the well. Due to this difference in exposure, it is important to consider difernet methos of estimation of Net Pay regarding vertical and horizontal wells. The objective os this work is to use azimuthal density logs to make diferent Net Pay estimations. To achieve the objectives of this project, two studies were made. The first study consists of the use of azimuthal density logs to generate diferent Net Pay estimations. The second, consists of the analysis of different image contrast enhancement algorithms to help on the identification of geological features, supporting the Net Pay analysis. The logs used on this work are from an oil productive well drilled in turbidites of the brazilian east coast. In this well, it was possible to identify a few geological features, such as sandstone and shale (beds), carbonate ciment and geological faults. As a result of the Net Pay calcualtion of the diferent density logs, it was possible to identify a difference of up to 10.72% Net Pay in the same well. The final Net Pay estimated from the volumetric density, up density, down density, up or down density and density image was respectively: 88.42%, 91.44%, 89.86%, 96.62% e 99.14%. Regarding the image contrast enhancement algorithms, 14 diferent algorithms from the space domain were applied to the selected density image, allowing a better visualization of several geological features, such as geological contacts, beds and faults. The algorithms that presented the best results in this image were the 2nd order derivative, gray level slicing and normalized histogram. Conclusions of this project are that each geological feature located at the well, affects the azimuthal and image logs in different ways, so, the use of different logs and image contrast enhancement algorithms can identify which density curves should be used in different depths of the well in order to obtain the most accurate Net Pay / Mestrado / Reservatórios e Gestão / Mestre em Ciências e Engenharia de Petróleo

Made available in DSpace on 2016-12-23T14:08:13Z (GMT). No. of bitstreams: 1 Breno Almeida Dornelas - parte 1.pdf: 376911 bytes, checksum: b45e88c007da3db1f74fa38428506e5c (MD5) Previous issue date: 2009-12-22 / A remoção eficiente de cascalhos ainda é um desafio na perfuração de poços para produção de óleo e gás. O ponto crítico corresponde ao estágio horizontal da perfuração que intrinsecamente tende a formar um leito de partículas sedimentadas na parte inferior do poço em perfuração. A erosão desse leito de cascalhos oriundos do solo perfurado depende principalmente da tensão de cisalhamento promovida pelo escoamento do fluido de perfuração. Utilizando uma bancada experimental, composta de sistema para circulação de fluidos, caixa de cascalhos, unidade de bombeio e equipamentos de medição, investiga-se a tensão de cisalhamento mínima necessária para a erosão de um leito em função das propriedades do fluido e das partículas do leito. A área de observação consiste de uma caixa abaixo da linha de escoamento, para partículas calibradas de areia, em um duto de acrílico. Para as medições iniciam-se as bombas com baixa rotação e são feitos incrementos de freqüência. A cada patamar de freqüência são capturadas imagens de partículas carreadas pelo escoamento, registrando a vazão estabelecida. Com a análise do processamento das imagens define-se o momento em que o carreamento das partículas deixa de ser aleatório e esporádico e começa a ser permanente. A tensão de cisalhamento é determinada pela Correlação PKN (de Prandtl, von Kármán e Nikuradse) a partir da vazão mínima necessária para o arraste. Os resultados são obtidos para o escoamento de água e de solução águaglicerina / The efficient hole cleaning is still a challenge in the wellbore drilling for production of oil and gas. The critical point is the horizontal drilling that inherently tends to produce a bed of sediment particles at the bottom of the well. The erosion of this cuttings bed depends mainly on the shear stress promoted by the flow of drilling fluid. The shear stress required to drag cuttings bed is investigate according to the fluid and particles properties, using an experimental assembly, composed of a loop for circulation of fluids, of a particle box, of a pump system, camera and measuring equipment. The area of observation consists of a box below the line of flow, for calibrated sand particles, in an acrylic duct. The test starts with the pumps in low frequency and are made the increments. At each level of frequency are captured images of particles carried and it is records the established flow rate. The erosion criteria is defined when the drag particle no longer be random and sporadic, and begins to be permanent. The shear stress is determined by the PKN correlation (by Prandtl, von Kármán, and Nikuradse) from the minimum flow rate necessary to start the erosion process. Results were obtained for the flow of water; and of water and glycerin solution

Workers involved in hydraulic fracking processes are exposed to various types of chemicals and dusts in their workplaces, such as proppants, which hold open the fissures created in the fracking process. Recently, ceramic proppants have been developed that may be less hazardous to workers than traditional proppants. Pulmonary function testing of workers producing ceramic proppant was used to assess the potential inhalation hazards of ceramic proppant. Male workers (n = 100) from a producer of ceramic proppant were evaluated with pulmonary function test data collected and evaluated using The American Thoracic Society (ATS) acceptability criteria. A comparison group was selected from the Third National Health and Nutrition Examination Survey (NHANES III) spirometry laboratory subset. No pulmonary function deficits were found in the worker group in comparison to the NHANES III population. Multiple linear regression analysis showed that the mean FEV1 and FVC values in workers were 0.11 and 0.08 liters respectively, and were greater as compared to the NHANES III population. Curiously, an FEV1/FVC ratio of less than 0.8, when compared to the NHANES III group, produced an odds ratio of 0.44 in worker group, indicating less risk of preclinical pulmonary dysfunction. Overall, exposure to ceramic proppant was not found to produce an adverse impact on pulmonary function in workers engaged in the manufacture of ceramic proppant.

No description available.

Master of Science / Department of Chemical Engineering / James Edgar / In the past decade the technique of horizontal drilling and hydraulic fracturing has been improved so much that it has become a cost effective method to extract natural gas from shale formations deep below the earth’s surface. Natural gas extraction has boomed in the past few years in the United States, enough that it has driven prices to an all time low. The amount of natural gas reserves in the U.S. has led to claims that it can lead the country to energy independence. It has also been touted as a cleaner fuel for electricity generation and to power vehicles. This report explains hydraulic fracturing and horizontal drilling particularly with regards to utilizing the techniques for natural gas extraction from shale gas. It also discusses the environmental impact due to the drilling and gas extraction. It demonstrates that although the natural gas beneath the U.S. is a valuable resource, the impacts to the planet and mankind are not to be taken lightly. There is the potential for the effects to be long term and detrimental if measures are not taken now to control them. In addition although on the surface natural gas seems to be a greener fuel, particularly in comparison to gasoline, it is also considered worse for the environment.

The large amount of produced oil and gas come from conventional resources all over the world and these resources are being depleted rapidly. This fact and the increasing oil and gas prices force the producing countries to find and search for new methods to recover more oil and gas. In order to meet the demand, the oil and gas industry has been turning towards to unconventional oil and gas reservoirs which become more popular every passing day. In recent years, they are seriously considered as supplementary to the conventional resources although these reservoirs cannot be produced at an economic rate or cannot produce economic volumes of oil and gas without assistance from massive stimulation treatments, special recovery processes or advanced technologies. The vast increase in demand for petroleum and gas has encouraged the new technological development and implementation. A wide range of technologies have been developed and deployed since 1980. With the wellbore technology, it is possible to make use of highly deviated wellbores, extended reach drilling, horizontal wells, multilateral wells and so on. All of the new technologies and a large number of new innovations have allowed development of increasingly complex economically marginal fields where shale gas and coal bed methane are found. In this study, primary target is to compare different production methods in order to obtain better well performance and improved production from different types of reservoirs. It is also be given some technical information regarding the challenges such as hydraulic fracturing and multilateral well configuration of the unconventional gas reservoir modeling and simulation. With the help of advances in algorithms, computer power, and integrated software, it is possible to apply and analyze the effect of the different well trajectories such as vertical, horizontal, and multilateral well on the future production performance of coal bed methane, shale gas, and tight gas reservoirs. A commercial simulator will be used to run the simulations and achieve the best-case scenarios. The study will lead the determination of optimum production methods for three different reservoirs that are explained above under the various circumstances and the understanding the production characteristic and profile of unconventional gas systems.

No description available.

The process of natural gas recovery by horizontal drilling and hydraulic fracturing, known as fracking, is a major scientific advance in unconventional energy development. Attention has largely been focused on its economic advantages and potential negative environmental repercussions, while less consideration given to its social dimensions. The purpose of this study was to explore the social consequences of fracking for communities in the Appalachian Basin's Marcellus shale. Research questions focused on the role of stakeholders and the resource needs of localities in shaping public policy. This study was guided by the tenets of the Boomtown theory along with key issues in fracking research such as environmental impacts, water resources, public health and safety, economics, and ethical concerns. An embedded case study research design was employed, using a purposive sample of 8 economic and policy subject matter experts from the 3 most prolific drilling counties in Pennsylvania. Data were collected by semi-structured interviews and were analyzed using open and axial coding with cross-case comparison. Results suggested that positive economic social consequences of fracking involved sustainability in providing generational and employment stability. Negative consequences, such as traffic, damaged infrastructure, and housing shortages, were temporary and manageable. Logistical and demographic information were valuable resources for community leadership, and stakeholders favored autonomy in decision making. The implications for social change include informing policy makers how to prepare the local workforce to be adaptable, establish sufficient infrastructure to support change, and educate communities to leverage opportunity in advance of new industry.

The assignment given to us by NCC was to compose a degree project based on ground excavations for power cables. The aim of the study was to examine suitable excavation methods depending on different possible terrain conditions. The amount of previously written material within this subject is nearly non- existent and therefore there is a genuine interest by the NCC to receive a compilation of different production methods. The greater part of this study is based upon interviews with several companies active within this area of expertise. The technique of placing the electricity grid beneath ground for safety is today getting more and more common. The aftermath of the hurricane “Gudrun” has forced several power companies to re-evaluate their electric supply network, which has lead to more placements of power cables underground. We have come to the conclusion that there are several factors that would affect the method of choice for cable excavations. Costumer demands, obstacles and the difference in ground conditions are vital factors behind the verdict for suitable production methods.