Experimental Study of Sand Particle Concentration Profiles in Straight and Pipe Elbow for Horizontal Multiphase Flows

2014 ◽  
Vol 136 (3) ◽  
Author(s):  
N. R. Kesana ◽  
R. Vieira ◽  
B. S. McLaury ◽  
S. A. Shirazi

Sand production is one of the major concerns for oil and gas producers. If production fluid velocities are not controlled properly, the produced sand may erode the pipelines which may result in pipe failures and halt the production causing economical losses as well as environmental issues. In order to better understand the erosion mechanism and improve current erosion models, it would be beneficial to identify the distribution of sand flowing inside the pipe. Therefore, sand sampling was performed at five different locations inside a 0.0732 m (3 in.) diameter horizontal pipe at L/D ∼ 150 using a pitot-style tube 6.35 mm (0.25 in.) in diameter. The probe was moved transversely from the top of the pipe and the face of the probe is facing the fluid flow to achieve sampling close to isokinetic conditions. Additionally, sampling experiments were conducted using the fixed mounted ports at the pipe wall. Using the fixed mounted ports, sampling is conducted both in a straight pipe section and elbow section. Experiments were performed in two different multiphase flow patterns (slug and wavy-annular) using two different particle sizes (150 μm and 300 μm) and three different liquid viscosities (1 cP, 10 cP, 40 cP). The influence of particle diameter, liquid viscosity, and the flow pattern on the sand distribution profiles will be discussed. From the experimental data, the recommended approaches for flowing concentration measurements are discussed. Finally, the implications of the sand concentration measurements on erosion are mentioned.

2020 ◽  
Vol 26 (3) ◽  
pp. 685-697
Author(s):  
O.V. Shimko

Subject. The study analyzes generally accepted approaches to assessing the value of companies on the basis of financial statement data of ExxonMobil, Chevron, ConocoPhillips, Occidental Petroleum, Devon Energy, Anadarko Petroleum, EOG Resources, Apache, Marathon Oil, Imperial Oil, Suncor Energy, Husky Energy, Canadian Natural Resources, Royal Dutch Shell, Gazprom, Rosneft, LUKOIL, and others, for 1999—2018. Objectives. The aim is to determine the specifics of using the methods of cost, DFC, and comparative approaches to assessing the value of share capital of oil and gas companies. Methods. The study employs methods of statistical analysis and generalization of materials of scientific articles and official annual reports on the results of financial and economic activities of the largest public oil and gas corporations. Results. Based on the results of a comprehensive analysis, I identified advantages and disadvantages of standard approaches to assessing the value of oil and gas producers. Conclusions. The paper describes pros and cons of the said approaches. For instance, the cost approach is acceptable for assessing the minimum cost of small companies in the industry. The DFC-based approach complicates the reliability of medium-term forecasts for oil prices due to fluctuations in oil prices inherent in the industry, on which the net profit and free cash flow of companies depend to a large extent. The comparative approach enables to quickly determine the range of possible value of the corporation based on transactions data and current market situation.


Author(s):  
Paul Stevens

This chapter is concerned with the role of oil and gas in the economic development of the global economy. It focuses on the context in which established and newer oil and gas producers in developing countries must frame their policies to optimize the benefits of such resources. It outlines a history of the issue over the last twenty-five years. It considers oil and gas as factor inputs, their role in global trade, the role of oil prices in the macroeconomy and the impact of the geopolitics of oil and gas. It then considers various conventional views of the future of oil and gas in the primary energy mix. Finally, it challenges the drivers behind these conventional views of the future with an emphasis on why they may prove to be different from what is expected and how this may change the context in which producers must frame their policy responses.


2018 ◽  
Vol 58 (2) ◽  
pp. 557
Author(s):  
Barry A. Goldstein

Facts are stubborn things; and whatever may be our wishes, our inclinations, or the dictates of our passion, they cannot alter the state of facts and evidence (Adams 1770). Some people unfamiliar with upstream petroleum operations, some enterprises keen to sustain uncontested land use, and some people against the use of fossil fuels have and will voice opposition to land access for oil and gas exploration and production. Social and economic concerns have also arisen with Australian domestic gas prices tending towards parity with netbacks from liquefied natural gas (LNG) exports. No doubt, natural gas, LNG and crude-oil prices will vary with local-to-international supply-side and demand-side competition. Hence, well run Australian oil and gas producers deploy stress-tested exploration, delineation and development budgets. With these challenges in mind, successive governments in South Australia have implemented leading-practice legislation, regulation, policies and programs to simultaneously gain and sustain trust with the public and investors with regard to land access for trustworthy oil and gas operations. South Australia’s most recent initiatives to foster reserve growth through welcomed investment in responsible oil and gas operations include the following: a Roundtable for Oil and Gas; evergreen answers to frequently asked questions, grouped retention licences that accelerate investment in the best of play trends; the Plan for ACcelerating Exploration (PACE) Gas Program; and the Oil and Gas Royalty Return Program. Intended and actual outcomes from these initiatives are addressed in this extended abstract.


Author(s):  
Shahani Kariyawasam ◽  
Warren Peterson

Reliability methods have being adopted by oil and gas operators for integrity management decisions. These methods explicitly account for all relevant uncertainties and are designed to provide consistent safety. Consequently, a risk or reliability based approach is a very appropriate basis for decision making in the face of uncertainties. However, as in the effective use of any powerful methodology the sensitivities of the method to assumptions and limitations of applicability need to be well understood. This paper presents how improvements were made to reliability based integrity program by understanding its limitations and sensitivities. First the inputs that have the highest impact on the results were identified. These inputs are the most appropriate areas for improvement and data gathering. It is also very important to understand how the results are to be used and for what purpose. The results of this particular inline inspection based reliability assessment are used to make better excavation and repair decisions. A defect-based and joint-based decision making process is essential for determining with sufficient confidence if each defect and joint is in a safe condition. Consequently, the improvements are focused on discriminating between the myriad of defects found during an inline inspection run. Distinct field characteristics of corrosion growth are also taken into account in these improvements. The paper presents the implementation of effective area methods for future integrity probabilistic evaluations. It also describes the benefit of applying defect-specific growth rates. Finally, case studies are presented to demonstrate the effectiveness of the changes.


2010 ◽  
Vol 132 (7) ◽  
Author(s):  
Afshin Goharzadeh ◽  
Peter Rodgers ◽  
Chokri Touati

This paper presents an experimental study of three-phase flows (air-water-sand) inside a horizontal pipe. The results obtained aim to enhance the fundamental understanding of sand transportation due to saltation in the presence of a gas-liquid two-phase intermittent flow. Sand dune pitch, length, height, and front velocity were measured using high-speed video photography. Four flow compositions with differing gas ratios, including hydraulic conveying, were assessed for sand transportation, having the same mixture velocity. For the test conditions under analysis, it was found that the gas ratio did not affect the average dune front velocity. However, for intermittent flows, the sand bed was transported further downstream relative to hydraulic conveying. It was also observed that the slug body significantly influences sand particle mobility. The physical mechanism of sand transportation was found to be discontinuous with intermittent flows. The sand dune local velocity (within the slug body) was measured to be three times higher than the averaged dune velocities, due to turbulent enhancement within the slug body.


Author(s):  
Risa Okita ◽  
Yongli Zhang ◽  
Brenton S. McLaury ◽  
Siamack A. Shirazi ◽  
Edmund F. Rybicki

Zhang et al (2006) utilized CFD to examine the validity of erosion models that have been implemented into CFD codes to predict solid particle erosion in air and water for Inconel 625. This work is an extension of Zhang’s work and is presented as a step toward obtaining a better understanding of the effects of fluid viscosity and sand particle size on measured and calculated erosion rates. The erosion rates of Aluminum 6061-T6 were measured for direct impingement conditions of a submerged jet. Fluid viscosities of 1, 10, 25, and 50 cP and sand particle sizes of 20, 150, and 300 μm were tested. The average fluid speed of the jet was maintained at 10 m/s. Erosion data show that erosion rates for the 20 and 150 μm particles are reduced as the viscosity is increased, while surprisingly the erosion rates for the 300 μm particles do not seem to change much for the higher viscosities. For all viscosities considered, larger particles produced higher erosion rates, for the same mass of sand, than smaller particles. Concurrently, an erosion equation has been generated based on erosion testing of the same material in air. The new erosion model has been compared to available models and has been implemented into a commercially available CFD code to predict erosion rates for a variety of flow conditions, flow geometries, and particle sizes. Since particle speed and impact angle greatly influence erosion rates of the material, calculated particle speeds were compared with measurements. Comparisons reveal that, as the particles penetrate the near wall shear layer, particles in the higher viscosity liquids tend to slow down more rapidly than particles in the lower viscosity liquids. In addition, CFD predictions and particle speed measurements are used to explain why the erosion data for larger particles is less sensitive to the increased viscosities.


2021 ◽  
Vol 05 ◽  
Author(s):  
Nima Norouzi

: One of the focal points of the global energy struggle in recent years has been storytelling in the Eastern Mediterranean. Greece and the Greek Cypriot government (GCA), in cooperation with Egypt and Israel, are implementing a containment strategy against Turkey and the Turkish Republic of Northern Cyprus (TRNC) in the region. Turkey’s response to this plan was an exclusive agreement with Libya. Turkey and Libya have signed a memorandum of understanding between the government of national reconciliation on limiting the maritime jurisdiction of the new continental shelf in the Eastern Mediterranean - the only borders of the lottery’s economic zone. Greece could act with other countries, and it is said that Turkey’s competence will be ratified in the face of agreements that may restrict movement. The United States and the European Union (EU) also sought to share gas with European countries against Turkey, Israel, and the GCA. This article focuses on Libya’s ongoing competition, given Libya’s oil geopolitics and challenges in the eastern Mediterranean region. This paper briefly investigates the energy geopolitics in the eastern Mediterranean and North African region; this paper aims to conclude the diverse opinions led by various interests and points of view and propose a solution for the ever-growing tensions in this region.


2016 ◽  
Vol 852 ◽  
pp. 459-465 ◽  
Author(s):  
Vikas Kannojiya ◽  
Satish Kumar ◽  
Mani Kanwar ◽  
S.K. Mohapatra

Erosion is a serious problem faced in many industries that includes the transport of sand and water slurry in slurry pipe line. This paper emphasizes on the investigation of erosion on a mild steel straight pipe at different parameters including fluid velocity, particle size and concentration. The fluid velocity is selected in the range of 2.5-10 m/s using computational fluid dynamics code ANSYS-CFX. Sand particle within the size range of 100-400 µm size and concentration 5%-15% are used in this study. An Euler-Lagrange approach is used to solve the multiphase flow phenomenon. A horizontal pipe of diameter 100 mm and length 1 m (10 times of diameter) is considered for the study. The stochastic model of Sommerfeld will be used to account the wall roughness of pipe. It is also observed that the erosion wear in the pipeline strongly depends on fluid velocity, particle size and concentration.


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