Flow Characteristics of Surfactant Solutions in Porous Media and Their Role in Permeability Modification

1981 ◽  
Vol 21 (06) ◽  
pp. 709-720 ◽  
Author(s):  
B. Kalpakci ◽  
E.E. Klaus ◽  
J.L. Duda ◽  
R. Nagarajan
Keyword(s):  
Porous Medium ◽  
Porous Media ◽  
Bulk Viscosity ◽  
Effective Viscosity ◽  
Flow Characteristics ◽  
Surfactant Solution ◽  
Surface Characteristics ◽  
Initial Permeability ◽  
Permeability Reduction ◽  
Surfactant Solutions

Kalpakci, B., SPE, Standard Oil Co. (Ohio) Klaus, E.E., Pennsylvania State U. Pennsylvania State U. Duda, J.L., SPE, Pennsylvania State U. Pennsylvania State U. Nagarajan, R., Pennsylvania State U. Pennsylvania State U. DECEMBER 1981 Abstract This paper presents results of a study on flow properties of surfactant solutions in porous media, properties of surfactant solutions in porous media, using the Penn State porous media viscometer. The effects of permeability, shear rate, and surface characteristics of porous media on the flow of oil- and water-external microemulsions, as well as surfactant solutions with lamellar structures, are examined. Untreated Bradford and Berea sand- stones, oil- and water-wet treated sandstones, and filter papers are used as porous media. The study shows that the effective viscosity of the surfactant solution (as measured in porous media), on the basis of initial permeabilities, is greater than the bulk viscosity (as measured by conventional viscometers). This increase is small for Newtonian surfactant solutions but is quite substantial for non- Newtonian surfactant solutions. The difference between bulk and effective viscosities of Newtonian surfactant solutions is eliminated when the effective viscosity is determined on the basis of the final permeability of the porous medium to calibration permeability of the porous medium to calibration solution. This indicates that the permeability of the porous medium during now of these Newtonian porous medium during now of these Newtonian surfactant solutions is equal to that during flow of postcalibration solutions. In contrast, in the case of postcalibration solutions. In contrast, in the case of the non-Newtonian surfactant solution with lamellar structures, the effective viscosity based on the final permeability remains higher than the bulk viscosity permeability remains higher than the bulk viscosity of the solution. Plausible explanations for the lower permeability during surfactant flow compared with permeability during surfactant flow compared with the final permeability, in this case, are discussed. It is found that the flow of surfactant solutions causes a permanent decrease in the permeability of the porous. medium. Initial permeability is not restored even by thorough flushing of the porous medium with surfactant-free brine solution. Residual permeability reductions of 2 to 51% are observed. permeability reductions of 2 to 51% are observed. The residual permeability reduction increases with decreasing initial permeability. The residual permeability reduction is relatively insensitive to the type permeability reduction is relatively insensitive to the type of surfactant solution. However, it depends on surface characteristics of the porous medium and decreases in this order: untreatedfired is greater th an oil-wet treated. Introduction According to Gogarty, about 60% of the potential oil reserves are estimated to be amenable to chemical flooding with surfactant and polymers. In surfactant/polymer flooding, the interaction of various chemicals with each other and with reservoir fluids and rocks, the permeability, the porosity, and the operating conditions are critical factors in determining the effectiveness of the process. Many studies of surfactant systems have been carried out relating to phase behavior, interfacial tension, and retention or adsorption characteristics. But only a few studies have been conducted on flow characteristics in porous media of surfactant fluids prepared with petroleum sulfonates, hydrocarbons, prepared with petroleum sulfonates, hydrocarbons, water, and electrolytes. These latter studies have not examined fully the flow characteristics over a wide range of permeabilities and shear rates, the influence of the permeability of porous media on the residual permeability reduction, and the influence of surface permeability reduction, and the influence of surface characteristics of porous media. Considering that sufficient viscosity level is an essential factor in mobility control during surfactant flooding, the importance of the rheology of surfactant solution in porous media is quite obvious. Information on porous media is quite obvious. Information on injectivity, effective viscosity, and permeability modification during the flow of surfactant solutions is also essential. SPEJ P. 709

scholarly journals Jeffrey Fluid Flow through Porous Medium in the Presence of Magnetic Field in Narrow Tubes

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Santhosh Nallapu ◽  
G. Radhakrishnamacharya
Keyword(s):  
Magnetic Field ◽  
Porous Medium ◽  
Fluid Flow ◽  
Effective Viscosity ◽  
Equations Of Motion ◽  
Flow Characteristics ◽  
Darcy Number ◽  
Jeffrey Fluid ◽  
Tube Radius ◽  
The Core

Jeffrey fluid flow in the presence of magnetic field through porous medium in tubes of small diameters is studied. It is assumed that the core region consists of a Jeffrey fluid and the peripheral region of a Newtonian fluid. Making the assumptions as in the work of Chaturani and Upadhya, the linearised equations of motion have been solved and analytical solution has been obtained. The influence of various pertinent parameters on the flow characteristics such as effective viscosity, core hematocrit, and mean hematocrit has been studied and discussed through graphs. It is found that the effective viscosity and mean hematocrit decrease with Jeffrey parameter and Darcy number but increase with tube hematocrit and tube radius. Also, the core hematocrit decreases with Jeffrey parameter, Darcy number, tube hematocrit, and tube radius. Further, it is noticed that the flow exhibits the anomalous Fahraeus-Lindquist effect.

The Flow of Foam Through Short Porous Media And Apparent Viscosity Measurements

1966 ◽  
Vol 6 (01) ◽  
pp. 17-25 ◽  
Author(s):  
S.S. Marsden ◽  
Suhail A. Khan
Keyword(s):  
Porous Medium ◽  
Porous Media ◽  
Shear Rate ◽  
Relative Permeability ◽  
Oil Recovery ◽  
Apparent Viscosity ◽  
Viscosity Ratio ◽  
Surfactant Solution ◽  
Liquid Saturation ◽  
Liquid Displacement

Abstract Externally generated foam was injected continuously into short porous media. Both flow rate and pressure drop were measured. Liquid saturation was determined by electrical conductivity. Foam quality G, expressed as the ratio of gas volume to total volume, was varied from 0.70 to 0.96. As measured with a modified Fann VG Meter, apparent viscosity of this foam µa decreases with increasing shear rate but usually falls within the range of 50 to 500 cp. At a given shear rate, µa increases almost linearly with G. When measured with a Bendix Ultraviscoson, kinematic µa is independent of r but absolute µa increases with r from about 3 to 8 cp. The effective permeability-apparent viscosity ratio ke/µa decreases almost linearly with G for porous media of high permeability, but the rate of decrease becomes less for tighter ones. The relative permeability-apparent viscosity ratio kr/µa vs G data does not fall on a single line. The kr/µa ratio increases with liquid saturation in the porous medium and with surfactant concentration. Estimates of µa for foam in porous media vary from 30 to 100 cp. INTRODUCTION Although research on the development of a foam-drive, oil recovery process has been going on for almost a decade, most of the significant publications have appeared within the last several years. This illustrates well the rate at which interest in this process is accelerating. Bond and Holbrook1 were the first to describe the use of foam to improve oil recovery in their patent of 1958. They proposed that an aqueous foaming agent slug be injected into the formation and that this be followed by gas to produce a foam in situ. Fried2 studied the injection of foam into porous media which has already been subjected to conventional gas or water drives and found that gas could be used to drive a foam bank which would, in turn, displace additional oil in the form of an oil bank. He attributed the increased oil recovery to the high effective viscosity of foam flowing in porous media. His microscopic observations showed the importance of foam generation and regeneration within the porous medium. By injecting both air and aqueous surfactant solution, Bernard3 generated foams within the porous medium in which oil displacement was being studied. In a separate empirical test, he also measured the dynamic foaming characteristics of the same surfactants in water and/or oil. With some exceptions and for the seven surfactants studied, there seems to be a qualitative relationship between the efficiency of liquid displacement and the dynamic foaming test used. This relationship was not consistent enough to eliminate the necessity of actual foam flood tests in porous media for surfactant selection. In a study basic to gas storage in aquifers, Bennett4 described the displacement of brine by foam in consolidated porous media. Among other things, he stated that the ability of a surfactant solution to foam is more important than the stability of its foam. The presence of a foam bank between the displacing air and the displaced brine improved both breakthrough and ultimate recovery. In a continuation of this work Kolb5 attributed the great reduction in surfactant solution production rate as displacement by air progressed to a decrease in relative permeability to gas. These several effects reported by both Bennett and Kolb can all be attributed to the high apparent viscosity of foam which was obviously flowing in the porous media.

The Mechanism of Gas and Liquid Flow Through Porous Media in the Presence of Foam

1968 ◽  
Vol 8 (04) ◽  
pp. 359-369 ◽  
Author(s):  
L.W. Holm
Keyword(s):  
Porous Medium ◽  
Porous Media ◽  
Liquid Flow ◽  
Effective Permeability ◽  
Mobility Ratio ◽  
Reservoir Rock ◽  
Porous System ◽  
Foam Flow ◽  
Surfactant Solutions ◽  
Flow Through

Abstract This study shows that in the presence of foam, gas and liquid flow separately through porous media representative of reservoir rock. These results were obtained by using tracer techniques to measure the flow of the gas and liquid comprising the foam. Foam does not flow through the porous medium as a body even when the liquid and gas are combined outside the system and injected as foam Instead the liquid and gas forming the foam separate as the foam films break and then re-form in the porous system. Liquid moves through the porous medium via the film network of the bubbles and gas moves progressively through the system by breaking and re-forming bubbles throughout the length of the flow path. The flow rates of the gas and liquid are a function of the number and strength of the films in the porous medium. There is no free flow of gas; i.e., no continuous gas phase. On the basis of these results, foam can be expected to improve a waterflood or gas drive by decreasing the permeability of the reservoir rock to a displacing liquid or gas. This improves the mobility ratio and thus the conformance of the flood. Introduction Foam is formed when gas and a solution of a surface active agent are injected into a porous medium either simultaneously or intermittently. During the past few years, several papers have been published on the subject of foam flow in porous media. Foam has been used successfully in the removal of capillary water blocks from producing formations. The use of foam in gas storage reservoirs to reduce gas leaks and to increase storage capacity has been considered in recent years. Foam has also been investigated as an oil displacing agent, and as an agent to improve the mobility ratio in a waterflood. However, the mechanism by which the gas and liquid phases comprising the foam flow through a porous medium has not been described adequately. Normally, when two immiscible phases (gas and liquid) flow concurrently through a porous medium, each phase follows separate paths or channels. At given saturations of the two phases, a certain number of channels are available to each phase, and as saturations change, the number and configuration of the channels available for each phase also change. The effective permeability of each phase is a function of the saturation of that phase only, and the flow of each phase can be described by Darcy's law. When foam is present, the effective permeability of the porous medium to each phase is greatly reduced compared with permeabilities measured in the absence of foam. Based upon the observed flow of surfactant solutions and gas in capillaries, it has been concluded that the gas and liquid may flow separately or they may flow combined as foam. At least four mechanisms have been postulated to explain how fluids flow with foam present:A large portion of the gas is trapped in the porous medium and a small fraction flows as free gas, following Darcy's law.The foam structure moves as a body; the rate of gas flow is the same as the rate of liquid flow.Gas flows as a discontinuous phase by breaking and re-forming films. Liquid flows as a free phase.A portion of the liquid and gas move as a foam body while excess surfactant solution moves as a free phase. It also has been suggested that different flow mechanisms exist for high quality (dry) foams made from dilute surfactant solutions and for foams made from more concentrated solutions. Studies conducted on the flow of foam through capillaries have shown that a plug-type flow occurs and that foam flows as a body.

scholarly journals Colloid clogging of saturated porous media under varying ionic strength and roughness during managed aquifer recharge

2019 ◽  
Vol 9 (3) ◽  
pp. 225-231 ◽  
Author(s):  
Du Xinqiang ◽  
Song Yalin ◽  
Ye Xueyan ◽  
Luo Ran
Keyword(s):  
Porous Medium ◽  
Porous Media ◽  
Ionic Strength ◽  
Smooth Surface ◽  
Saturated Porous Medium ◽  
Managed Aquifer Recharge ◽  
Permeability Reduction ◽  
Saturated Porous Media ◽  
Aquifer Recharge ◽  
Pore Throat

Abstract Column experiments were conducted to examine the clogging effects of colloids under controlled conditions of solution ionic strength (IS) and porous media roughness. The results showed that colloids in recharge water play an important role in the clogging process of saturated porous media, such that even a small amount of colloid may cause a large reduction in the permeability of the porous medium. Clogging at the pore throat was inferred to be the main reason for the severe permeability reduction of porous media. The characteristics of colloid clogging were clearly influenced by both IS and medium roughness. Recharge water with a higher IS facilitated greater attachment of colloids to the surface of the saturated porous medium, which lead to superficial clogging, while collectors with a rough surface resulted in greater clogging than collectors with a smooth surface.

Shear Viscosities of Ionic Polyacrylamide Solutions

1972 ◽  
Vol 12 (06) ◽  
pp. 469-473 ◽  
Author(s):  
Necmettin Mungan
Keyword(s):  
Porous Medium ◽  
Porous Media ◽  
Shear Rate ◽  
Polymer Solution ◽  
Polymer Solutions ◽  
Mobility Control ◽  
Permeability Reduction ◽  
Experimental Conditions ◽  
Molecular Weights ◽  
Stock Solutions

Abstract Solutions of ionic polyacrylamide polymers behave pseudoplastic in purely viscometric flow. Flow rate, polymer molecular weight and electrolytes affect solution viscosities to a large extent. Equations are given for the viscosity-shear rate relations in a form that can be used conveniently to account for the effect of viscosity on mobility. Introduction Polymers are being used increasingly in oil recovery operations, and therefore, an understanding of their flow behavior is gaining pragmatic importance. Past studies have shown that in the flow of polymeric fluids through porous media, the increase in solution viscosity, decrease in permeability, and viscoelastic deformations cause permeability, and viscoelastic deformations cause the fluid mobility to be greatly reduced. In general, viscoelasticity, i.e., extensional flow, is not so important because, for the largest part of a reservoir, polymer solution moves at very low and fairly steady polymer solution moves at very low and fairly steady velocities. Jennings et al. have concluded this for the specific polymers that they studied. Permeability reduction plays an important role in Permeability reduction plays an important role in the mobility control, particularly in porous media having low permeabilities initially. Reductions ranging from 25 to 70 times have been reported. However, the alterations that take place in a porous medium during polymer flow, the coupling between the geometry of the porous medium and the properties of the flowing fluid, and the influence of the flow regime on permeability have not been looked into in sufficient detail. A separate study, directed to the understanding of these important phenomena is required. In the present work, the purely viscous behavior of solutions of three partially hydrolized polyacrylamide polymers was obtained under experimental conditions far polymers was obtained under experimental conditions far more extensive than any reported in the literature. Some data have been available in the past for two of the polymers, but the third is a new polymer for which no data have been reported before. Using a Weissenberg rheogoniometer, Cannon-Fenske viscometers, and various capillary cubes, viscosities were measured over 8 decades of shear rate, ranging from 10 to to 10 (5) sec-1. These are the limits of measurable rates of shear and cover those that may apply to flow in reservoirs. Distilled water and various NaCl solutions were used as solvents to afford comparison of the rheological properties between fresh and saline solutions. Measurements were also made with solutions containing calcium' and magnesium to study the effect of divalent cations. EXPERIMENTAL The three polymers, Nos. 500, 700 and NC 1870, are partially hydrolized polyacrylamides manufactured by The Dow Chemical Co., and were from lots 8085, 52 and 87-8100E, respectively. Polymer NC 1870 is currently at a developmental stage and can be obtained in limited quantities; the other two have been available commercially for some time, have been used in the laboratory and in the field. All three are hydrolized to the same extent, containing approximately 25 percent polyacrylate, with the remainder being polyacrylamide. The molecular weights of Nos. 500 and 700 are 2 to 3 and 3 to 7 million, respectively. That of the NC 1870 is higher, but has not been measured due to the usual difficulties in measuring such high molecular weights. Polymer and salt concentrations are given on a weight-parts per million basis. Reagent grade chemicals and double-distilled deaerated water, having a pH of 6.5, were used in all solutions. Formaldehyde was added as a bactericide. To the extent possible, air was kept out of the solutions to avoid oxidation-type degradation of the polymers. Polymer solutions were mixed using magnetic Polymer solutions were mixed using magnetic stirrers and carefully avoiding any mechanical degradation. Solutions of desired concentrations were prepared from stock solutions by dilution. The latter had been passed through 1-micron millipore filters, were optically clear, containing no fish-eyes. The polymer concentration of stock solutions was determined by turbidimetry and nitrogen analysis, the two methods usually agreeing within a few percent. percent. SPEJ P. 469

Analysis of Factors Influencing Mobility and Adsorption in the Flow of Polymer Solution Through Porous Media

1974 ◽  
Vol 14 (04) ◽  
pp. 337-346 ◽  
Author(s):  
G.J. Hirasaki ◽  
G.A. Pope
Keyword(s):  
Porous Medium ◽  
Porous Media ◽  
Polymer Solution ◽  
Polymer Adsorption ◽  
Rock Properties ◽  
Dimensionless Number ◽  
Permeability Reduction ◽  
Flow Rates ◽  
System Properties ◽  
Effective Pore Radius

Abstract Displacement of oil by polymer solution has several unique characteristics that are not present in normal waterflooding. These include non-Newtonian effects, permeability reduction, and polymer adsorption. polymer adsorption. The rheological behavior of the flow of polymer solution through porous media could be Newtonian at low flow rates, pseudoplastic at intermediate flow rates, and dilatant at high flow rates. The pseudoplastic behavior is modeled with the pseudoplastic behavior is modeled with the Blake-Kozeny model for power-law model fluids. The dilatant behavior is modeled with the viscoelastic properties of the polymer solution. properties of the polymer solution. The reduction in permeability is postulated to be due to an adsorbed layer of polymer molecular coils that reduces the effective size of the pores. A dimensionless number has been formulated to correlate the permeability reduction factor with the polymer, brine, and rock properties. This polymer, brine, and rock properties. This dimensionless number represents the ratio of the size of the polymer molecular coil to an effective pore radius polymer molecular coil to an effective pore radius of the porous medium.A model has been developed to represent adsorption as a function of polymer, brine, and rock properties. The model assumes that the polymer is properties. The model assumes that the polymer is adsorbed on the surface of the porous medium as a monolayer of molecular coils that have a segment density greater than the molecular coil in dilute solution. Introduction Displacement of oil by polymer solutions has several unique characteristics that are not present in normal waterflooding. These include non-Newtonian effects, permeability reduction, and polymer adsorption. In principle, the effects could polymer adsorption. In principle, the effects could be measured experimentally for each fluid-rock system of interest over the entire range of flow conditions existing in the reservoir. However, there are seldom complete data on all systems of interest. A correlation that represents these effects as a function of the polymer, brine, rock properties, and flow conditions would result in a more accurate evaluation of systems that may not have been measured in the laboratory at the desired conditions. Moreover, if the dependence of these effects on the system properties were known, it would aid the search for an optimal system. A model is proposed for representing the effects as a function of the system properties. The model is consistent with a number of experimental observations but enough data have not yet been acquired to determine the extent of applicability of a correlation. It is hoped that the presentation of these models will encourage further research to verify or improve the models. MODEL FOR PSEUDOPLASTIC FLOW THROUGH POROUS MEDIA The Blake-Kozeny model represents the porous medium as a bundle of capillary tubes with a length that is greater than the length of the porous medium by a tortuosity factor, tau. The equivalent radius of the capillary tubes can be related to the particle diameter of a packed bed from the hydraulic radius concept or to the permeability and porosity by comparison with Darcy's law for Newtonian fluids.The modified Blake-Kozeny models represents the flow of a power-law fluid in the capillaries. The relationship between the pressure drop and flow rate can be expressed as a product of the friction factor and Reynolds number.(1) This expression can be related to the apparent viscosity and the rock permeability and porosity through the following relationships:(2) where(3) SPEJ P. 337

Conservative solute transport with periodic velocity and sinusoidal source concentration in semi-infinite porous media: An analytical solution

2014 ◽  
Vol 6 (1) ◽  
pp. 1024-1031
Author(s):  
R R Yadav ◽  
Gulrana Gulrana ◽  
Dilip Kumar Jaiswal
Keyword(s):  
Porous Medium ◽  
Porous Media ◽  
Laplace Transformation ◽  
Seepage Velocity ◽  
Transformation Technique ◽  
Numerical Examples ◽  
One Dimensional ◽  
Porous Domain ◽  
Conservative Solute Transport ◽  
Source Concentration

The present paper has been focused mainly towards understanding of the various parameters affecting the transport of conservative solutes in horizontally semi-infinite porous media. A model is presented for simulating one-dimensional transport of solute considering the porous medium to be homogeneous, isotropic and adsorbing nature under the influence of periodic seepage velocity. Initially the porous domain is not solute free. The solute is initially introduced from a sinusoidal point source. The transport equation is solved analytically by using Laplace Transformation Technique. Alternate as an illustration; solutions for the present problem are illustrated by numerical examples and graphs.

Capillary Imbibition Dynamics in Porous Media

2014 ◽  
Author(s):  
Swayamdipta Bhaduri ◽  
Pankaj Sahu ◽  
Siddhartha Das ◽  
Aloke Kumar ◽  
Sushanta K. Mitra
Keyword(s):  
Porous Medium ◽  
Porous Media ◽  
Paper Strip ◽  
Capillary Imbibition ◽  
Flow Physics ◽  
Fundamental Understanding ◽  
Paper Based Microfluidics ◽  
To Come

The phenomenon of capillary imbibition through porous media is important both due to its applications in several disciplines as well as the involved fundamental flow physics in micro-nanoscales. In the present study, where a simple paper strip plays the role of a porous medium, we observe an extremely interesting and non-intuitive wicking or imbibition dynamics, through which we can separate water and dye particles by allowing the paper strip to come in contact with a dye solution. This result is extremely significant in the context of understanding paper-based microfluidics, and the manner in which the fundamental understanding of the capillary imbibition phenomenon in a porous medium can be used to devise a paper-based microfluidic separator.

Mass Transport Modelling in Porous Media Using Delay Differential Equations

2006 ◽  
Vol 258-260 ◽  
pp. 586-591
Author(s):  
António Martins ◽  
Paulo Laranjeira ◽  
Madalena Dias ◽  
José Lopes
Keyword(s):  
Porous Media ◽  
Differential Equations ◽  
Mass Transport ◽  
Delay Differential Equations ◽  
Dispersion Model ◽  
Flow Characteristics ◽  
Convective Transport ◽  
Transport Modelling ◽  
Flow Field Characteristics ◽  
Delay Differential

In this work the application of delay differential equations to the modelling of mass transport in porous media, where the convective transport of mass, is presented and discussed. The differences and advantages when compared with the Dispersion Model are highlighted. Using simplified models of the local structure of a porous media, in particular a network model made up by combining two different types of network elements, channels and chambers, the mass transport under transient conditions is described and related to the local geometrical characteristics. The delay differential equations system that describe the flow, arise from the combination of the mass balance equations for both the network elements, and after taking into account their flow characteristics. The solution is obtained using a time marching method, and the results show that the model is capable of describing the qualitative behaviour observed experimentally, allowing the analysis of the influence of the local geometrical and flow field characteristics on the mass transport.

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