The session will cover an area of growing interest, given increasing concern about wellbore integrity and well control. As with other MPD systems, SMD technology offers early detection of influxes (kicks) and minimizes downhole losses to weak subsurface formations. This paper describes a number of system enhancements, including the ability to display and analyze not only the critical parameters of drilling hydraulics but also other information that allows different perspectives in considering the closed-loop system. The paper demonstrates the successful application of advanced automated managed-pressure-drilling (MPD) technologies on the Dover well close to Fort McMurray, Alberta, Canada. The development of the Kanowit field offshore Sarawak, Malaysia, requires the drilling of two subsea development wells with a semisubmersible rig.
The contract is helping to solidify Europe’s offshore sector as the focal point for the rise of automated drilling technology. This paper presents a case history of drilling automation system pilot deployment, including the use of wired drillpipe, on an Arctic drilling operation. In this paper, the application of a real-time T&D model is demonstrated. The process of T&D analysis was automated, and the time and cost required to run physical models offline was reduced or, in some cases, eliminated. The latest example of the offshore sector's march toward automated wellbore construction will take shape later this year in the North Sea.
Showing concern for the high emission of green house gases, the governments all over the world are coming up with more stringent rules to check the emission level. Steam Assisted Gravity Drainage is a highly energy intensive process where huge amount of steam is generated by heating natural gas or coal thereby generating a very large share of green house gases. Therefore, solar energy seems to be lucrative in the following ways: world areas with abundant solar irradiation level can be tapped to reduce the fossil fuel consumption, minimizing the cost spent on fossil fuel and the emissions level at the same time. Concentrated Solar Power (CSP) looks a very promising technique but it comes with its own limitations mainly due to the requirement for huge area for setting up the solar collectors. Water Soluble Carbon-N115 is a sub-micrometer particle that has size less than the wavelength of light. Due to this reason, instead of scattering light, it absorbs light. The nano-particle gets enveloped in a thin layer of steam when put in a water bath. The vapour is released after reaching liquid-air interface and the nano-particles revert back to the solution to repeat the vaporization process and they exchange heat with the fluid, slightly raising the fluid temperature resulting in boiling of the fluid volume as a parallel effect. The paper discusses a model incorporating this nano-particle for the reduction of solar field footprint by more than a quarter and thereby reducing the cost and operational area. The paper also suggests the places across the globe where the proposed method can be deployed for generating steam and ultimately injecting it for producing oil above the surface from a tar-sand reservoir.
Xiong, Hao (University of Oklahoma) | Huang, Shijun (China University of Petroleum, Beijing) | Devegowda, Deepak (University of Oklahoma) | Liu, Hao (China University of Petroleum, Beijing) | Li, Hao (University of Oklahoma) | Padgett, Zack (Univiersity of Oklahoma)
Hao Xiong, University of Oklahoma; Shijun Huang, China University of Petroleum, Beijing; Deepak Devegowda, University of Oklahoma; Hao Liu, China University of Petroleum, Beijing; and Hao Li and Zack Padgett, University of Oklahoma Summary Steam-assisted gravity drainage (SAGD) is the most-effective thermal recovery method to exploit oil sand. The driving force of gravity is generally acknowledged as the most-significant driving mechanism in the SAGD process. However, an increasing number of field cases have shown that pressure difference might play an important role in the process. The objective of this paper is to simulate the effects of injector/producer-pressure difference on steam-chamber evolution and SAGD production performance. A series of 2D numerical simulations was conducted using the MacKay River and Dover reservoirs in western Canada to investigate the influence of pressure difference on SAGD recovery. Meanwhile, the effects of pressure difference on oil-production rate, stable production time, and steam-chamber development were studied in detail. Moreover, by combining Darcy's law and heat conduction along with a mass balance in the reservoir, a modified mathematical model considering the effects of pressure difference is established to predict the SAGD production performance. Finally, the proposed model is validated by comparing calculated cumulative oil production and oil-production rate with the results from numerical and experimental simulations. The results indicate that the oil production first increases rapidly and then slows down when a certain pressure difference is reached. However, at the expansion stage, lower pressure difference can achieve the same effect as high pressure difference. In addition, it is shown that the steam-chamber-expansion angle is a function of pressure difference. Using this finding, a new mathematical model is established considering the modification of the expansion angle, which (Butler 1991) treated as a constant. With the proposed model, production performance such as cumulative oil production and oil-production rate can be predicted. The steam-chamber shape is redefined at the rising stage, changing from a fanlike shape to a hexagonal shape, but not the single fanlike shape defined by (Butler 1991). This shape redefinition can clearly explain why the greatest oil-production rate does not occur when the steam chamber reaches the caprock.
Exploration in 2018 got off to a strong start when the Chevron-operated Ballymore well encountered 205 m of net oil pay in the US Gulf of Mexico. Drilled by Pacific Drilling’s Sharav deepwater drillship, the well reached a total depth of 8,898 m. Global discovered oil and gas resources and big project sanctions are expected to remain on the upswing through next year, according to separate industry outlooks from Rystad Energy and Wood Mackenzie. Internalizing lessons from a difficult last few years, operators are choosing investments more wisely and now better prepared to deal with volatile oil markets, the consultancies concluded. "Portfolios are set to weather low prices, and the recent slide in prices justifies the sector’s conservative mindset."
Na, Li (Faculty of Geographical Science, Beijing Normal University, 100875, Beijing, China) | Jinliang, Zhang (Faculty of Geographical Science, Beijing Normal University, 100875, Beijing, China) | Jinshui, Liu (Shanghai Branch, CNOOC Ltd., 200030, Shanghai, China) | Wenlong, Shen (Shanghai Branch, CNOOC Ltd., 200030, Shanghai, China) | Hao, Chen (Shanghai Branch, CNOOC Ltd., 200030, Shanghai, China) | Guangchen, Xu (Faculty of Geographical Science, Beijing Normal University, 100875, Beijing, China)
Summary The prediction of source rocks is very important to the basin at the initial stage of exploration, among which the description of the source rocks' spatial distribution and the evaluation of the source rocks' thickness are the most significant. For most of the oil and gas fields on the land, the prediction and evaluation of source rocks rely on geochemistry analysis. But well data is inadequate on the offshore exploration area. Therefore, seismic data and geophysical methods can be applied to improve the prediction accuracy of source rocks. Data and Method In this research, the main data relate to core, logging, seismic from Lishui Sag, China (Figure 1).
Simon, Matthieu (Schlumberger) | Tkabladze, Avto (Schlumberger) | Beekman, Sicco (Schlumberger) | Atobatele, Timothy (Schlumberger) | De Looz, Marc-André (Schlumberger) | Grover, Rahul (Schlumberger) | Hamichi, Farid (Schlumberger) | Jundt, Jacques (Schlumberger) | McFarland, Kevin (Schlumberger) | Mlcak, Justin (Schlumberger) | Reijonen, Jani (Schlumberger) | Revol, Arnaud (Schlumberger) | Stewart, Ryan (Schlumberger) | Yeboah, Jonathan (Schlumberger) | Zhang, Yi (Schlumberger)
Formation bulk density is classically measured by irradiating the formation with gamma rays emitted by a 137Cs source, and counting the Compton scattered photons returning to the gamma-ray detectors in the well-logging instrument. Finding a suitable replacement for the 137Cs source has been difficult. The X-ray source described in this paper appears to be a robust replacement for this type of source.
The continued success of 137Cs sources in density logging shows that attempts at their replacement have been unsuccessful due to the insufficient measurement quality or lack of practicality of alternative logging instruments.
An X-ray density-pad sonde was engineered to measure bulk density without a radioisotopic source. The pad contains a rugged, compact X-ray generator with an endpoint energy larger than 300 keV. The core of the tool is the generator, which emits a controlled, focused, stable X-ray flux into the formation. The scattered X-rays are detected by strategically placed scintillation detectors. The pad-tool architecture significantly reduces the effects of standoff and borehole rugosity compared to a mandrel design.
Modeling and experimental data show that the physics of the formation density measurement using a sonde with an X-ray generator and scintillation detectors can be described in the same way as the traditional density measurement, which is based on a monoenergetic gammaray source. Although the 137Cs gamma-ray source density measurement and the X-ray density measurement differ in the relative magnitude of the responses to formation density and lithology (photoelectric factor, PEF), the fundamental physics is the same. An endpoint energy above 300 keV ensures that the transport and attenuation of X-rays in the formation are dominated by Compton scattering, like the attenuation of gamma rays from a 137Cs source. The contribution of the photoelectric absorption to the attenuation of the X-rays is increased, but remains much smaller than the effect of Compton scattering, making the corrections for lithology and borehole fluid straightforward.
A characterization database was acquired to probe the physics of the measurement and to derive robust density and PEF algorithms. Plots of near- and far-detector count rates for different mudcake thicknesses and mud types show spine-and-ribs behavior like 137Cs-based density tools. Field logs acquired with the new tool show improved precision and vertical resolution compared to the 137Cs source tools suggesting that this new tool may be a viable replacement for the older tools.
This paper presents a drilling solution through application of an automated managed-pressure-drilling (MPD) technique proved to identify and react to actual wellbore pressures and detect and control gains and losses while still having the ability to maintain a constant bottomhole pressure (BHP) while drilling through tight windows. The paper demonstrates the successful application of advanced automated MPD technologies on the Dover well close to Fort McMurray, Alberta, Canada. A well in the Dover field had multiple failures in the liner that resulted in excessive sand production, causing the well to be shut in. After reviewing the options of well repair or redrilling the horizontal section to install a new slotted liner, it was determined that redrilling was the best option. After the well-schematic analysis and in collaboration with the operator, the combination of a proprietary control system and MPD techniques was recommended along with a water-based mud (WBM) weight to drill the well and still be able to maintain the BHP required to overbalance the formation.
Shell Offshore said it made a "large" deepwater discovery in the US Gulf of Mexico that it believes could be tied back to its Appomattox platform. The Anglo-Dutch firm's 100%-owned Dover well on Mississippi Canyon Block 612 encountered more than 800 ft of net pay in the Norphlet formation, marking Shell's sixth discovery in that formation since 2003. Drilled 170 miles southeast of New Orleans in 7,500 ft of water, the well reached a true vertical depth of 29,000 ft. The discovery is 13 miles from the Appomattox host platform, which recently arrived on location in the deepwater gulf. Production from the platform is expected to start before the end of next year, eventually peaking at 175,000 BOE/D.
The development of an offshore oil field is a complex and risky project. One core problem in this task is the selection of a production system that maximizes oil recovery and minimizes investments and operational costs while meeting external, economic, environmental, societal and technological demands in a scenario of uncertainties. Several studies address this problem in the literature; however, they do not consider uncertainties in the initial data neither justify objectively the chosen alternative among other feasible ones. We propose to select an offshore production system using an intelligent system that considers input uncertainties and chooses the best alternative in a rational manner. By comparing the results obtained with previous studies and real scenarios, we conclude that our methodology can obtain the optimal solution in situations where other methods cannot.