Download or read book Laboratory Evaluation of Proppant Transport in Complex Fracture Systems written by Rakshit Sahai and published by . This book was released on 2012 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Improvement of Fracture Conductivity Through Study of Proppant Transport and Chemical Stimulation written by Songyang Tong and published by . This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: During hydraulic fracturing treatments, proppants - usually sand - are placed inside fractures to improve fracture conductivity. However, a large portion of the generated hydraulic fractures often remain unpropped after fracturing treatments. There are two primary reasons for this poor proppant placement. First, proppants settle quickly in common fracturing fluids (e.g., slickwater), which results in unpropped sections at the tip or top of the fracture. Second, a large number of the microfractures are too narrow to accommodate any common commercial proppant. Such unpropped fractures hold a large potential flow capacity as they exhibit a large contact area with the reservoir. However, their potential flow capacity is diminished during production due to closing of unpropped fractures because of closure stress. In this study, fractures are categorized as wider fractures, which are accessible to proppant, and narrower fractures, which are inaccessible to proppant. For wider fractures, proppant transport is important as proppant is needed for keeping them open. For narrower fractures, a chemical formulation is proposed as there is less physical restriction for fluids to flow inside across them. The chemical formulation is expected to improve fracture conductivity by generating roughness on fracture surfaces. This dissertation uses experiments and simulations to investigate proppant transport in a complex fracture network with laboratory-scale transparent fracture slots. Proppant size, injection flow rate and bypass fracture angle are varied and their effects are systematically evaluated. Based on experimental results, a straight-line relationship can be used to quantify the fraction of proppant that flows into bypass fractures with the total amount of proppant injected. A Computational Fluid Dynamics (CFD) model is developed to simulate the experiments; both qualitative and quantitative matches are achieved with this model. It is concluded that the fraction of proppant which flows into bypass fractures could be small unless a significant amount of proppant is injected, which indicates the inefficiency of slickwater in transporting proppant. An alternative fracturing fluid - foam - has been proposed to improve proppant placement because of its proppant carrying capacity. Foam is not a single-phase fluid, and it suffers liquid drainage with time due to gravity. Additionally, the existence of foam bubbles and lamellae could alter the movement of proppants. Experiments and simulations are performed to evaluate proppant placement in field-scale foam fracturing application. A liquid drainage model and a proppant settling correlation are developed and incorporated into an in-housing fracturing simulator. Results indicate that liquid drainage could negatively affect proppant placement, while dry foams could lead to negligible proppant settling and consequently uniform proppant placement. For narrower fractures, two chemical stimulation techniques are proposed to improve fracture conductivity by increasing fracture surface roughness. The first is a nanoparticle-microencapsulated acid (MEA) system for shale acidizing applications, and the second is a new technology which can generate mineral crystals on the shale surface to act as in-situ proppants. The MEA could be released as the fracture closes and the released acid could etch the surface of the rock locally, in a non-uniform way, to improve fracture conductivity (up to 40 times). Furthermore, the in-situ proppant generation technology can lead to crystal growth in both fracking water and formation brine conditions, and it also improves fracture conductivity (up to 10 times) based on core flooding experiments

Download or read book Experimental and Modeling Evaluation of Proppant Transport in Complex Fractures written by Abla Rhouma and published by . This book was released on 2019 with total page 157 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Quantifying Ceramic Proppant Transport in Complex Fracture Networks written by Vivekvardhan Reddy Kesireddy and published by . This book was released on 2017 with total page 91 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Water fracs have become an essential part of unconventional reservoirs to create deeper fracture networks. Proppant transport in water fracs is challenging in terms of fluids ability to carry the proppant deeper into these fracture networks. This experimental study investigates the impact of the flow rates, fracture widths and complexity controlling the ability of proppant to flow into complex fracture networks. This research attempts to nullify the knowledge gap in understanding width heterogeneity in primary and secondary fractures. This study speaks for settling pattern and proppant transport through a slot flow model with a unique approach to understand stage wise distribution of proppant. The slurry was injected in multiple fracture pore volumes at required flow rates to monitor the stage-wise development of proppant bed. Study illustrates proppant transport in terms of proppant bed heights, equilibrium dune levels and proppant area fractions. Results represents proppant transport for fracture widths, which are comparable to proppant diameter. Two different configurations of apparatus were used to investigate heterogeneity in width in complex fracture networks. Results describe stepwise distribution of ceramic proppant under the influence of flow rates, fracture width and complexity. The bed height gradually builds up in the slot with each injection to achieve an equilibrium bed height. Injection slurry velocities primarily affect proppant transport affecting its distribution in fractures. The fracture width showed a significant impact on proppant transport. Width heterogeneity in complex fracture systems provide better proppant distribution in complex fracture networks. Heterogeneity of width in the fracture caused increased settling and more proppant surface area fractions. The results help in optimizing the proppant flow patterns into complex fracture networks"--Abstract, page iii.

Download or read book Proppant Transport in Complex Fracture Networks written by Christopher Allen Johnson Blyton and published by . This book was released on 2016 with total page 320 pages. Available in PDF, EPUB and Kindle. Book excerpt: Current hydraulic fracturing practice in unconventional resource development typically involves multiple fracturing stages, each consisting of the simultaneous creation of several fractures from a horizontal well. A large mass of proppant, often millions of pounds per well, is injected with the fluid to provide post-closure conductivity. Despite the large quantity of proppant used and its critical importance to well productivity, simple models are often applied to determine its placement in fractures. Propped or effective fracture lengths indicated by modeling may be 100 to 300% larger than the lengths inferred from production data. A common assumption is that the average proppant velocity due to pressure driven flow is equal to the average carrier fluid velocity, while the settling velocity calculation uses Stokes’ law. To more accurately determine the placement of proppant in a fracture, it is necessary to rigorously account for many effects not included in the above assumptions. In this study, the motion of particles flowing with a fluid between fracture walls has been simulated using a coupled computational fluid dynamics and discrete element method (CFD-DEM) that rigorously accounts for the both aspects of the problem. These simulations determine individual particle trajectories as particle to particle and particle to wall collisions occur and include the effect of fluid flow. The results show that the proppant concentration and the ratio of proppant diameter to fracture width govern the relative velocity of proppant and fluid. Proppant settling velocity has been examined for small fracture widths to delineate the effect of several independent variables, including concentration. Simulations demonstrate that larger concentration increases the average settling velocity, in apparent contrast with much of the available literature, which indicates that increased concentration reduces settling velocity. However, this is due to the absence of displacement driven counter current fluid flow. This demonstrates that proppant settling in a hydraulic fracture is more complex than usually considered. A proppant transport model developed from the results of the direct numerical simulations and existing correlations for particle settling velocity has been incorporated into a fully three-dimensional hydraulic fracturing simulator. This simulator couples fracture geomechanics with fluid flow and proppant transport considerations to enable the fracture geometry and proppant distribution to be determined rigorously. Two engineering fracture design parameters, injection rate and proppant diameter, have been varied to show the effect on proppant placement. This allows for an understanding of the relative importance of each and optimization of the treatment to a particular application. The presence of natural fractures in unconventional reservoirs can significantly contribute to well productivity. As proppant is transported along a hydraulic fracture, the presence of a dilated natural fracture forms a fluid accepting branch and may result in proppant entry. The proportion of proppant transported into a branch at steady state has been determined using the CFD-DEM approach and is presented via a dimensionless ‘particle transport coefficient’ through normalization by the proportion of fluid flowing into the branch. Reynolds number at the inlet, branch aperture and the angle of orientation between the main slot and branch, particle size and concentration each affect the transport coefficient. A very different physical process, which controls particle transport into a branch under certain conditions, is the formation of a stable particle bridge preventing subsequent particle transport into the branch. This phenomenon was observed in several simulation cases. The complete set of equations for a three-dimensional formulation of rectangular displacement discontinuity elements has been used to determine the width distribution of a hydraulic fracture and dilated natural fracture. The widths have been determined for several combinations of stress anisotropy, net pressure, hydraulic fracture height and length. The effect of the length, height and orientation of the natural fracture and the elastic moduli of the rock have also been examined. Of the cases examined, many show that natural fracture dilation does not occur. Further, of those cases where dilation is apparent, the proppant transport efficiency corresponding to the natural fracture width is significantly less than one and in many cases zero due to size exclusion. The location and orientation of the natural fracture do not significantly affect its width, while its length and the elastic moduli of the rock substantially change the width.

Download or read book Unconventional Shale Gas Development written by Rouzbeh G. Moghanloo and published by Gulf Professional Publishing. This book was released on 2022-02-23 with total page 498 pages. Available in PDF, EPUB and Kindle. Book excerpt: Unconventional Shale Gas Development: Lessons Learned gives engineers the latest research developments and practical applications in today’s operations. Comprised of both academic and corporate contributors, a balanced critical review on technologies utilized are covered. Environmental topics are presented, including produced water management and sustainable operations in gas systems. Machine learning applications, well integrity and economic challenges are also covered to get the engineer up-to-speed. With its critical elements, case studies, history plot visuals and flow charts, the book delivers a critical reference to get today’s petroleum engineers updated on the latest research and applications surrounding shale gas systems. Bridges the gap between the latest research developments and practical applications through case studies and workflow charts Helps readers understand the latest developments from the balanced viewpoint of academic and corporate contributors Considers environmental and sustainable operations in shale gas systems, including produced water management

Download or read book Mathematical Theory of Oil and Gas Recovery written by P. Bedrikovetsky and published by Springer Science & Business Media. This book was released on 2013-04-17 with total page 596 pages. Available in PDF, EPUB and Kindle. Book excerpt: It is a pleasure to be asked to write the foreword to this interesting new book. When Professor Bedrikovetsky first accepted my invitation to spend an extended sabbatical period in the Department of Mineral Resources Engineering at Imperial College of Science, Technology and Medicine, I hoped it would be a period of fruitful collaboration. This book, a short course and a variety of technical papers are tangible evidence of a successful stay in the UK. I am also pleased that Professor Bedrikovetsky acted on my suggestion to publish this book with Kluwer as part of the petroleum publications for which I am Series Editor. The book derives much of its origin from the unpublished Doctor of Science thesis which Professor Bedrikovetsky prepared in Russian while at the Gubkin Institute. The original DSc contained a number of discrete publications unified by an analytical mathematics approach to fluid flow in petroleum reservoirs. During his sabbatical stay at Imperial College, Professor Bedrikovetsky has refined and extended many of the chapters and has discussed each one with internationally recognised experts in the field. He received great encouragement and editorial advice from Dr Gren Rowan, who pioneered analytical methods in reservoir modelling at BP for many years.

Download or read book Slickwater Proppant Transport in Complex Hydraulic Fracture Networks written by Msalli A. Alotaibi and published by . This book was released on 2015 with total page 201 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Integrated 3 dimensional Modeling of Proppant Transport Through Hydraulic Fracture Network in Shale Gas Reservoir written by Oliver Chang and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Hydraulic fracturing is one of the most successful and widely applied techniques that ensure economic recovery from unconventional reservoirs. Oil and gas bearing formation has pre-existing natural fractures and possesses a large proportion in hydrocarbon resources. Distinct fracture propagational behavior and operational variation both affect the entire hydraulic fracturing treatment. Proppant transport and fracture network conductivity are the most significant factors determining the effectiveness of a treatment. The concept of stimulated reservoir volume (SRV) is used to characterize the efficiency of hydraulic fracturing treatment. However, the unpropped fracture will close after the well starts to produce without contributing hydrocarbon recovery. Only the propped open section of fracture contributes to the hydrocarbon recovery. Therefore, the concept of propped open stimulated reservoir volume (PSRV) is proposed to characterize the effectiveness of the treatment. Physics of proppant transport in a complex fracture network is unclear to the engineers. Most of the model simulates using simplified physics. In this work, we first identified the patterns of proppant transport and we developed equations to quantify the governing physics in each pattern, in order to capture the proppant transport process accurately. To quantify the PSRV, a dynamic 3-D, finite-difference, proppant transport model is developed and linked to a hydraulic fracture propagation model to simulate the process of proppant transport through the hydraulic fracture network. The actual propped open stimulated reservoir volume (PSRV) and fracture network conductivity can be quantified by utilizing the model. The goal of this study is to generate guidelines to maximize the effectiveness of the hydraulic fracturing treatment. Hence, a systematic parametric study was conducted to investigate the relation among engineering factors, geomechanical and reservoir properties. The effect of each parameter on PSRV, PSRV/SRV efficiency ratio, and average fracture conductivity during pressure pumping, flowback and shut-in is evaluate and quantified. Guidelines to optimize the effectiveness of hydraulic fracturing treatment for different scenarios are established based on the systematic parametric study.

Download or read book Unconventional Reservoir Geomechanics written by Mark D. Zoback and published by Cambridge University Press. This book was released on 2019-05-16 with total page 495 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive overview of the key geologic, geomechanical and engineering principles that govern the development of unconventional oil and gas reservoirs. Covering hydrocarbon-bearing formations, horizontal drilling, reservoir seismology and environmental impacts, this is an invaluable resource for geologists, geophysicists and reservoir engineers.

Download or read book Rock Fractures and Fluid Flow written by National Research Council and published by National Academies Press. This book was released on 1996-08-27 with total page 568 pages. Available in PDF, EPUB and Kindle. Book excerpt: Scientific understanding of fluid flow in rock fracturesâ€"a process underlying contemporary earth science problems from the search for petroleum to the controversy over nuclear waste storageâ€"has grown significantly in the past 20 years. This volume presents a comprehensive report on the state of the field, with an interdisciplinary viewpoint, case studies of fracture sites, illustrations, conclusions, and research recommendations. The book addresses these questions: How can fractures that are significant hydraulic conductors be identified, located, and characterized? How do flow and transport occur in fracture systems? How can changes in fracture systems be predicted and controlled? Among other topics, the committee provides a geomechanical understanding of fracture formation, reviews methods for detecting subsurface fractures, and looks at the use of hydraulic and tracer tests to investigate fluid flow. The volume examines the state of conceptual and mathematical modeling, and it provides a useful framework for understanding the complexity of fracture changes that occur during fluid pumping and other engineering practices. With a practical and multidisciplinary outlook, this volume will be welcomed by geologists, petroleum geologists, geoengineers, geophysicists, hydrologists, researchers, educators and students in these fields, and public officials involved in geological projects.

Download or read book Investigating the Performance of High Viscosity Friction Reducers Used for Proppant Transport During Hydraulic Fracturing written by Mohammed Salem Ba Geri and published by . This book was released on 2019 with total page 174 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Over the last few recent years, high viscosity friction reducers (HVFRs) have been successfully used in the oil and gas industry across all premier shale plays in North America including Permian, Bakken, and Eagle Ford. However, selecting the most suitable fracture fluid system plays an essential role in proppant transport and minimizing or eliminating formation damage. This study investigates the influence of the use of produced water on the rheological behavior of HVFRs compared to a traditional linear guar gel. Experimental rheological characterization was studied to investigate the viscoelastic property of HVFRs on proppant transport. In addition, the successful implication of utilizing HVFRs in the Wolfcamp formation, in the Permian Basin was discussed. This study also provides a full comparative study of viscosity and elastic modulus between HVFRs and among fracturing fluids such as xanthan, polyacrylamide-based emulsion polymer, and guar. The research findings were analyzed to reach conclusions on how HVFRs can be an alternative fracture fluid system within many unconventional reservoirs. Compared to the traditional hydraulic fracture fluid system, the research shows the many potential advantages that HVFR fluids offer, including superior proppant transport capability, almost 100% retained conductivity, around 30% cost reduction, and logistics such as minimizing chemical usage by 50% and the ability to stoner operation equipment on location. Finally, this comprehensive investigation addresses up-to-date of using HVFRs challenges and emphasizes necessities for using HVFRs in high TDS fluids"--Abstract, page iv.

Download or read book Modeling of Solid Particle Transport in Fractures and Its Applications to Proppant Placement During Hydraulic Fracturing Operations written by Yanan Ding and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: In addition to conventional enhanced oil recovery (EOR) technologies, extensive efforts have been made to explore new approaches to sustain the increasing global oil and gas consumption while lowering the operational costs. In recent decades, nanoparticles (NPs) have seen their promising potentials in recovering hydrocarbons from numerous laboratory experiments and field pilots. Also, hydraulic fracturing techniques have unlocked a significant quantity of hydrocarbon resources from unconventional reservoirs. Solid particle transport including NP transport, dispersion, and distribution in hydrocarbon reservoirs, proppant placement within hydraulic fractures, and sand production is critical to the efficient and effective hydrocarbon exploitation. Considering the petrophysical complexity as well as the intricate interactions among particles, fluids, and rock matrix, it is, therefore, an extremely challenging task to accurately predict the associated transport and placement behaviour of solid particles in a hydrocarbon reservoir. Theoretically, a robust and pragmatic method has been developed and validated to analytically determine the dynamic dispersion coefficients for particles flowing in a parallel-plate fracture with instantaneous point source as well as uniform and volumetric line sourcess, in which particle gravity settling effect has been considered. It is found that the point source and the uniform line source are respectively the most and least sensitive to the gravity effect. An increase of particle size larger than its critical value decreases the asymptotical dispersion coefficient for all the source conditions, while gravity settling promotes the dispersion phenomenon during the early-stage of point source condition. Particle-tracking simulations have been performed and validated on polydisperse dense particle transport in a randomly-orientated fracture with spatially variable apertures. The simulated results indicate that the mass breakthrough efficiency of particles and particle plume distribution in a randomly-orientated rough fracture are significantly influenced by different factors when particle gravity settling occurs. In addition, particle attachment consisting of reversible and irreversible adsorptions on an aperture surface is quantified applying the Derjaguin-Landau-Verwey-Overbeek (DLVO) kinetics. With sensitivity analysis performed, the impacts of different factors on particle attachment are found to vary with each other through non-unique patterns. By integrating the Perkins-Kern-Nordgren-Carter (PKN-C) fracture propagation model and the particle tracking algorithm, a novel Eulerian-Lagrangian (E-L) model has been developed and validated to simulate field-scale proppant transport during hydraulic fracturing operations. Such an E-L model incorporates pertinent empirical correlations determined from regressing experimental measurements regarding the proppant settling velocity and the drag/lift forces, which is applicable to both the Newtonian and non- Newtonian fluid conditions. The non-Newtonian fluid is usually found to yield a less "heel-biased" pattern of proppant distribution in a hydraulic fracture, e.g., a larger slurry coverage together with a longer proppant dune, while distinct patterns of the dominant factors are observed and evaluated.

Download or read book Modeling of Proppant Transport Through Hydraulic Fracture Network written by Oliver Chih-Young Chang and published by . This book was released on 2014 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Development of Unconventional Reservoirs written by Reza Rezaee and published by MDPI. This book was released on 2020-04-16 with total page 522 pages. Available in PDF, EPUB and Kindle. Book excerpt: The need for energy is increasing and but the production from conventional reservoirs is declining quickly. This requires an economically and technically feasible source of energy for the coming years. Among some alternative future energy solutions, the most reasonable source is from unconventional reservoirs. As the name “unconventional” implies, different and challenging approaches are required to characterize and develop these resources. This Special Issue covers some of the technical challenges for developing unconventional energy sources from shale gas/oil, tight gas sand, and coalbed methane.

Download or read book Hydraulic Proppant Fracturing and Gravel Packing written by D. Mader and published by Elsevier. This book was released on 1989-03-01 with total page 1277 pages. Available in PDF, EPUB and Kindle. Book excerpt: Many aspects of hydraulic proppant fracturing have changed since its innovation in 1947. The main significance of this book is its combination of technical and economical aspects to provide an integrated overview of the various applications of proppants in hydraulic fracturing, and gravel in sand control. The monitoring of fractures and gravel packs by well-logging and seismic techniques is also included.The book's extensive coverage of the subject should be of special interest to reservoir geologists and engineers, production engineers and technologists, and well log analysts.

Download or read book Effect of Fracture Heterogeneity on Proppant Transport and Settling Mechanism written by Dhurgham Abdulameer Kadhim and published by . This book was released on 2017 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Proppant transport modeling through fractures with slickwater fluid systems assumes uniform and homogeneous fracture widths by implying constant fluid behavior at wall boundaries. Hydraulic fracturing mineback operations have demonstrated that induced fractures are heterogeneous and varying in width. This work investigates the impact of fracture width heterogeneity, roughness, and leak-off on ceramic proppant transport and settling, using proppant distribution concepts of Equilibrium Dune Level (EDL) and equilibrium Dune Length (EDX). Experimental work was conducted to investigate the impact of fracture width heterogeneity by varying fracture width along two plexiglass sheets. To mimic actual hydraulic fractures, the injection side was designed as the largest width, and the width of the opposite end was reduced. The ratio between the injection and tip side widths was varied to study the effect of changing fracture width. One ratio was used as a base to study the effect of varying wall roughness and leak-off on the proppant placement. Results of this work demonstrate the impacts of reservoir heterogeneity, wall roughness, and leak off on proppant conveyance and distribution. Fracture width and wall roughness have a significant effect on proppant distribution along a fracture. Increasing width heterogeneity and roughness provide a better proppant distribution and thus better fracture propped conductivity. The effect of leak-off on proppant distribution was monitored, and it showed that proppant followed water movement. Consequently, average water volume that left the slot was affected by proppant distribution"--Abstract, page iii.