Download or read book Sweep Efficiency for Solvent Injection Into Heavy Oil Reservoirs at Grain scale Displacement of Extremely Viscous Fluid written by Okhtay Taghizadeh Dizaj Cheraghi and published by . This book was released on 2007 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The movement of low viscosity fluid through a porous medium containing extremely viscous fluid is emerging as an important phenomenon in several petroleum engineering applications. These include the recovery of heavy oil by solvent injection, the preferential reduction of water flow using polymer gels, and the enhancement of acid fracturing treatments. The displacement of one fluid from a porous medium by a second, immiscible fluid has been extensively studied in two cases: when capillary forces are dominant, and when viscous forces are comparable to capillary forces. This dissertation research examines a third case: when viscous forces are dominant. The viscosity of the fluid initially present in the porous medium is four or more orders of magnitude greater than the viscosity of the displacing fluid. Consequently, the displacement through an individual pore will be dictated by the hydrodynamic forces required to move the high viscosity fluid. However, very little is known about grain-scale behavior of such displacements. The research will develop a mathematical model of the viscosity-dominated displacement in a network of conduits. By neglecting pressure drop within the low viscosity fluid, the model will treat the displacement as a moving boundary problem. The high viscosity fluid will be assumed Newtonian and will move in response to the pressure gradient imposed via the low viscosity fluid. The movement can be treated as pseudo-steady state flow of the highviscosity fluid. The flow field will be updated whenever the low viscosity fluid advances into a pore previously occupied by high-viscosity fluid. Swept volume will be calculated in each run for comparison and further investigation. We will use classical methods for direct and iterative solutions of large, sparse linear systems to compute these steady states. Key practical insights to be obtained from the model are the nature of the displacement and effects of geometry and hydraulic conductivities on the sweep efficiency. The model will form the basis for examining additional physical processes, notably mass transfer between fluids, and the possibility that fingering of the low viscosity fluid occurs within individual pore throats.

Download or read book Improvement of Sweep Efficiency in Gasflooding written by and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Miscible and near-miscible gasflooding has proven to be one of the few cost effective enhance oil recovery techniques in the past twenty years. As the scope of gas flooding is being expanded to medium viscosity oils in shallow sands in Alaska and shallower reservoirs in the lower 48, there are questions about sweep efficiency in near-miscible regions. The goal of this research is to evaluate sweep efficiency of various gas flooding processes in a laboratory model and develop numerical tools to estimate their effectiveness in the field-scale. Quarter 5-spot experiments were conducted at reservoir pressure to evaluate the sweep efficiency of gas, WAG and foam floods. The quarter 5-spot model was used to model vapor extraction (VAPEX) experiments at the lab scale. A streamline-based compositional simulator and a commercial simulator (GEM) were used to model laboratory scale miscible floods and field-scale pattern floods. An equimolar mixture of NGL and lean gas is multicontact miscible with oil A at 1500 psi; ethane is a multicontact miscible solvent for oil B at pressures higher than 607 psi. WAG improves the microscopic displacement efficiency over continuous gas injection followed by waterflood in corefloods. WAG improves the oil recovery in the quarter 5-spot over the continuous gas injection followed by waterflood. As the WAG ratio increases from 1:2 to 2:1, the sweep efficiency in the 5-spot increases, from 39.6% to 65.9%. A decrease in the solvent amount lowers the oil recovery in WAG floods, but significantly higher amount of oil can be recovered with just 0.1 PV solvent injection over just waterflood. Use of a horizontal production well lowers the oil recovery over the vertical production well during WAG injection phase in this homogeneous 5-spot model. Estimated sweep efficiency decreases from 61.5% to 50.5%. In foam floods, as surfactant to gas slug size ratio increases from 1:10 to 1:1, oil recovery increases. In continuous gasflood VAPEX processes, as the distance between the injection well and production well decreases, the oil recovery and rate decreases in continuous gasflood VAPEX processes. Gravity override is observed for gas injection simulations in vertical (X-Z) cross-sections and 3-D quarter five spot patterns. Breakthrough recovery efficiency increases with the viscous-to-gravity ratio in the range of 1-100. The speed up for the streamline calculations alone is almost linear with the number of processors. The overall speed up factor is sub-linear because of the overhead time spent on the finite-difference calculation, inter-processor communication, and non-uniform processor load. Field-scale pattern simulations showed that recovery from gas and WAG floods depends on the vertical position of high permeability regions and k{sub v}/k{sub h} ratio. As the location of high permeability region moves down and k{sub v}/k{sub h} ratio decreases, oil recovery increases. There is less gravity override. The recovery from the field model is lower than that from the lab 5-spot model, but the effect of WAG ratio is similar.

Download or read book Chemical Enhanced Oil Recovery written by Patrizio Raffa and published by Walter de Gruyter GmbH & Co KG. This book was released on 2019-07-22 with total page 277 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book aims at presenting, describing, and summarizing the latest advances in polymer flooding regarding the chemical synthesis of the EOR agents and the numerical simulation of compositional models in porous media, including a description of the possible applications of nanotechnology acting as a booster of traditional chemical EOR processes. A large part of the world economy depends nowadays on non-renewable energy sources, most of them of fossil origin. Though the search for and the development of newer, greener, and more sustainable sources have been going on for the last decades, humanity is still fossil-fuel dependent. Primary and secondary oil recovery techniques merely produce up to a half of the Original Oil In Place. Enhanced Oil Recovery (EOR) processes are aimed at further increasing this value. Among these, chemical EOR techniques (including polymer flooding) present a great potential in low- and medium-viscosity oilfields. • Describes recent advances in chemical enhanced oil recovery. • Contains detailed description of polymer flooding and nanotechnology as promising boosting tools for EOR. • Includes both experimental and theoretical studies. About the Authors Patrizio Raffa is Assistant Professor at the University of Groningen. He focuses on design and synthesis of new polymeric materials optimized for industrial applications such as EOR, coatings and smart materials. He (co)authored about 40 articles in peer reviewed journals. Pablo Druetta works as lecturer at the University of Groningen (RUG) and as engineering consultant. He received his Ph.D. from RUG in 2018 and has been teaching at a graduate level for 15 years. His research focus lies on computational fluid dynamics (CFD).

Download or read book Field Study of Viscous Oil Production by Solvent Stimulation Wilmington California written by H. J. Lechtenberg and published by . This book was released on 1972 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Study of Hydrocarbon Miscible Solvent Slug Injection Process for Improved Recovery of Heavy Oil from Schrader Bluff Pool Milne Point Unit Alaska Quarterly Report January 1 1993 March 31 1993 written by and published by . This book was released on 1993 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: The ultimate objective of this three-year research project is to evaluate the performance of the hydrocarbon miscible solvent slug process and to assess the feasibility of this process for improving recovery of heavy oil from Schrader Bluff reservoir. This will be accomplished through measurement of PVT and fluid properties of Schrader Bluff oil, determination of phase behavior of Schrader Bluff oil solvent mixtures, asphaltene precipitation tests, slim tube displacement tests, core flood experiments and reservoir simulation studies. The expected results from this project include: determination of optimum hydrocarbon solvent composition suitable for hydrocarbon miscible solvent slug displacement process, optimum slug sizes of solvent needed, solvent recovery factor, solvent requirements, extent and timing of solvent recycle, displacement and sweep efficiency to be achieved and oil recovery. Work performed during quarter includes preliminary reservoir fluid characterization and multiple contact test runs using equation-of-state (EOS) simulator. Reservoir fluid samples are being acquired from Conoco Inc., and the process is expected to continue through the next quarter. Also, the experimental apparatus for the displacement study was set up.

Download or read book Transactions of the Society of Petroleum Engineers written by and published by . This book was released on 1995 with total page 488 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Experimental Measurement of Sweep Efficiency During Multi phase Displacement in the Presence of Nanoparticles written by Behdad Aminzadeh Goharrizi and published by . This book was released on 2013 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The efficiency of one fluid displacing another in permeable media depends greatly on the pore-scale dynamics at the main wetting front. Experiments have shown that the frontal dynamics can result in two different flow regimes: a stable and an unstable front. In stable displacements, any perturbation of the front will diminish with time and the effect of variation in permeability will be lessened. In contrast, in unstable displacements any perturbation of the front will grow with time and any variation in permeability will be magnified. In this dissertation, the stability of two different displacement processes are contemplated; a) vertical infiltration of dense liquid into dry sand from above and b) horizontal displacement of nanoparticle suspension with high pressure liquid CO2. Significant insights are obtained by measuring the in-situ flow patterns in real time with a light transmission method and CT scanning. Vertical infiltration of dense fluid into dry sands from above is often observed to be unstable and produce gravity driven fingers. The formation of gravity fingers can have large consequences on the sweep efficiency of a displacement. Infiltration experiments showed that gravity driven fingers have a unique saturation profile known as saturation overshoot with a higher saturation at the finger tips than the saturation at the finger tail. Despite the vast number of theoretical and experimental investigations, conditions under which the front is unstable, remain unclear. To determine what controls the saturation overshoot and how it relates to the dynamics at the initial wetting front, saturation overshoot was measured as a function of flux for seven different liquids. These liquids gave a range of molecular weights, viscosities, and vapor pressures. It is found that for each fluid there is a flux (called overshoot flux) below which saturation overshoot ceases and the front is diffuse. The magnitude of the overshoot flux depends inversely on the invading fluid's viscosity and shows little or no dependence on the invading fluid's surface tension, vapor pressure, or miscibility with water. Since the saturation overshoot is not described by the continuum multi-phase flow models, the experimental results are used to develop a semi-continuum model that bridges the continuum-scale and pore-scale physics. The proposed model predicts the observed dependence of overshoot on media permeability and invading fluid properties. At the planned depth for CO2 injection, either as an enhanced oil recovery technique or for CO2 storage, CO2 is typically less dense and less viscous than the in-situ fluid. Therefore, CO2 injection is unstable and produces viscous fingers. This can greatly reduce the efficiency of a CO2 flood or CO2 storage capacity of an aquifer. To remedy this behavior, surface treated nanoparticles were used to reduce the mobility of injected CO2. Displacement experiments were performed at low pressure with a CO2 analogue (n-octane) fluid and at high pressure with liquid CO2. Saturation distributions and pressure drops were measured in real time with the CT scanner when high pressure liquid CO2 or n-octane was used to displace brine in different cores with and without suspended nanoparticles. In the presence of nanoparticles, the displacement front is more spatially uniform with a later breakthrough compared to the same experiment with no suspended nanoparticles. These observations suggest that nanoparticle stabilized foam, which forms during the displacement, acts to suppress the instability. It is argued that the generation of droplets occurs at the leading front of all drainage displacements. In the presence of nanoparticles, these droplets are preserved when nanoparticle adhere at the fluid-fluid interface. The new mechanism for foam generation described here, provides an interesting alternative for mobility control in CO2 floods. Moreover, the same mechanism can potentially a) increase the CO2 storage capacity of an aquifer, b) enhance the CO2 capillary trapping, and c) provide an engineered barrier to CO2 leakage from a storage sites, thereby alleviating the risk of contaminating the overlying fresh groundwater resources for CO2 storage projects.

Download or read book Transactions of the Society of Petroleum Engineers written by American Institute of Mining, Metallurgical, and Petroleum Engineers and published by . This book was released on 1983 with total page 2170 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Study of Hydrocarbon Miscible Solvent Slug Injection Process for Improved Recovery of Heavy Oil from Schrader Bluff Pool Milne Point Unit Alaska Quarterly Report January 1 1994 March 31 1994 written by and published by . This book was released on 1994 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt: The ultimate objective of this three-year research project is to evaluate the performance of the hydrocarbon miscible solvent slug process and to assess the feasibility of this process for improving recovery of heavy oil from Schrader Bluff reservoir. This will be accomplished through measurement of PVT and fluid properties of Schrader Bluff oil, determination of phase behavior of Schrader Bluff oil solvent mixtures, asphaltene precipitation tests, slim tube displacement tests, core flood experiments and reservoir simulation studies. The expected results from this project include: determination of optimum hydrocarbon solvent composition suitable for hydrocarbon miscible solvent slug displacement process, optimum slug sizes of solvent needed, solvent recovery factor, solvent requirements, extent and timing of solvent recycle, displacement and sweep efficiency to be achieved and oil recovery. During this quarter, more displacement experiments in slim tube and miscible coreflood experiments have been conducted. Also, work has been initiated to match the slim tube displacement results using GEM, a compositional simulator developed by Computer Modelling Group.

Download or read book Society of Petroleum Engineers Journal written by Society of Petroleum Engineers of AIME. and published by . This book was released on 1983 with total page 1004 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Enhanced Solvent Vapour Extraction Processes in Thin Heavy Oil Reservoirs written by Xinfeng Jia and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book An Improved Vapour Solvent Injection Technique for Enhanced Heavy Oil Recovery written by Tao Jiang and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Theory and Application of Dimensional and Inspectional Analysis to Model Study of Fluid Displacements in Petroleum Reservoirs written by Albert Geyer Loomis and published by . This book was released on 1964 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Journal of Petroleum Technology written by and published by . This book was released on 1988 with total page 1230 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Development of Solvent Selection Criteria Based on Diffusion Rate Mixing Quality and Solvent Retrieval for Optimal Heavy oil and Bitumen Recovery at Different Temperatures written by Andrea Paola Marciales Ramirez and published by . This book was released on 2015 with total page 105 pages. Available in PDF, EPUB and Kindle. Book excerpt: Heavy-oil and bitumen recovery requires high recovery factors to offset the extreme high cost of the process. Attention has been given to solvent injection for this purpose and it has been observed that high recoveries are achievable when combined with steam injection. Heavier ("liquid") solvents (liquid at ambient conditions) are especially becoming more popular to be used in these processes due to availability and transportation. "Liquid" solvents are advantageous as they yield a better mixing quality (especially with very heavy-oils and bitumen) but a lower diffusion rate than lighter solvents like propane or butane. Despite this understanding, there is still not a clear screening criterion for solvent selection considering both diffusion rate and the quality of the mixture. Therefore, two main solvent selection criteria parameters--diffusion rate and mixing quality--were proposed to evaluate solvent injection efficiency at different temperatures for a defined set of solvent-heavy oil pairs of varying properties and composition. Diffusion rate, viscosity, and density reduction were among the test carried out through bulk liquid-liquid interaction. Then, core experiments at different temperatures were performed on Berea sandstone samples using the same set of oil-solvent pairs already defined to obtain the optimum carbon size (solvent type)-heavy oil combination that yields the highest recovery factor and the least asphaltene precipitation. Based on the fluid-fluid (solvent-heavy oil) interaction experiments and heavy-oil saturated rock-solvent interaction tests, the optimal solvent type was determined considering the fastest diffusion and best mixing quality for different oil-solvent combinations. In all these applications, the retrieval of expensive solvent is essential for the economics of the process. This led to a micro scale analysis to clarify the dynamics of solvent retrieval from matrix under variable temperatures at atmospheric pressure. The reasons of the entrapment of the solvent during this process were investigated for different wettability conditions, solvent type, and heating process carrying out visualization experiments on micromodels. The experimental and semi-analytical outcome of this research would be useful in determining the best solvent type for a given oil and in understanding the key factors that influence the quality of mixtures, including: (1) viscosity reduction and probable asphaltene precipitation, (2) the optimal solvent type considering the fastest recovery rate and ultimate recovery for different heavy oil-solvent combinations at different temperatures, and, (3) the visualization of the solvent recovery mechanisms at the pore scale.

Download or read book Study of Hydrocarbon Miscible Solvent Slug Injection Process for Improved Recovery of Heavy Oil from Schrader Bluff Pool Milne Point Unit Alaska Quarterly Report October 1 1993 December 31 1993 written by and published by . This book was released on 1993 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: The ultimate objective of this three-year research project is to evaluate the performance of the hydrocarbon miscible solvent slug process and to assess the feasibility of this process for improving recovery of heavy oil from Schrader Bluff reservoir. This will be accomplished through measurement of PVT and fluid properties of Schrader Bluff oil, determination of phase behavior of Schrader Bluff oil solvent mixtures, asphaltene precipitation tests, slim tube displacement tests, core flood experiments and reservoir simulation studies. The expected results from this project include: determination of optimum hydrocarbon solvent composition suitable for hydrocarbon miscible solvent slug displacement process, optimum slug sizes of solvent needed, solvent recovery factor, solvent requirements, extent and timing of solvent recycle, displacement and sweep efficiency to be achieved and oil recovery.

Download or read book A Study of Waterflood Sweep Efficiency in a Complex Viscous Oil Reservoir written by Marc Daniel Jensen and published by . This book was released on 2014 with total page 134 pages. Available in PDF, EPUB and Kindle. Book excerpt: West Sak is a multi-billion barrel viscous oil accumulation on the North Slope of Alaska. The unique geologic complexities and fluid properties of the West Sak reservoir make understanding ultimate sweep efficiency under waterflood a challenge. This project uses uncertainty modeling to evaluate the ultimate sweep efficiency in the West Sak reservoir and honors a rich dataset gathered from 30 years of development history. A sector model encompassing the area of the West Sak commercial pilot was developed and a sensitivity analysis conducted to determine the most important parameters affecting sweep efficiency. As part of this process unique constraints were incorporated into the model including measured saturations at the end of history, and observed completion performance. The workflow for this project was documented and can be adapted for use in larger scale models. The workflow includes the development of static cell properties which accurately represent field behavior, a preliminary history match using conventional methods and a sensitivity analysis employing a multi-run visualization tool to effectively navigate and process large amounts of data. The main contributions of this work include the identification of key parameters affecting sweep efficiency in the West Sak oil field, a documented workflow, and increased insight into observed production behavior.