Effect of Foam on Trapped Gas Saturation and on Permeability of Porous Media to Water

1965 ◽  
Vol 5 (04) ◽  
pp. 295-300 ◽  
Author(s):  
George G. Bernard ◽  
W.L. Jacobs
Keyword(s):  
Porous Medium ◽  
Porous Media ◽  
Pressure Gradient ◽  
Crude Oil ◽  
Oil Recovery ◽  
Free Water ◽  
Foaming Agent ◽  
Foaming Agents ◽  
Gas Saturation ◽  
Trapped Gas

Abstract The effect of foam on the permeability of porous media to water was studied as a function of foaming agent concentration, specific permeability, pressure gradient, length of a porous medium and its oil saturation. At a given fluid saturation in a porous medium, the permeability to water was found to be the same whether foam was present or not. Foam decreases the permeability to water by developing a higher trapped gas saturation than that obtained by water flooding without foam present. Increasing the concentration of foaming agent increased the trapped gas saturation and thereby decreased the permeability to water. The presence of oil reduced the capability of most foaming agents to decrease the permeability of a porous medium to water. A few surfactants were found to be effective foaming agents even in the presence of oil. These results are similar to those reported in a previous paper on the effect of foam on the permeability of porous media to gas. The effect of foam was found to persist in long porous media at moderately high reservoir temperatures and during the passage of many pore volumes of surfactant-free water. Introduction This paper describes part of a study on. a novel approach in the use of surfactants for oil recovery; the use of foam rather than water to displace oil. Previously it was found that foam can displace oil which normally is not displaced by water. The foam is formed by successively injecting a suitable surfactant solution and gas into a porous medium. Foam appears to have at least two uses in the field:it shows promise as a superior oil recovery agent, andit shows promise as a selective permeability reducing agent. Foam may be very useful in water floods, or in other oil recovery processes, where highly permeable streaks or unfavorable mobility ratios are a problem. A previous paper reported the effect of foam on the permeability of porous media to gas. In the present study the effect of foam on the permeability of porous media to water is reported. The specific objectives of the study were to determine:the effect of foam on the permeability to water in porous media of various specific permeabilities,the effect of foam on the permeability to water in the presence of oil,the effect of foam and crude oil on the trapped gas saturation,the effect of foam on permeability to water at trapped gas saturation,the effect of pressure gradient on the permeability to water under foaming conditions,the persistence of foam during the passage of surfactant-free water through the porous medium, andthe effect of various foaming agents, length of the porous medium and temperature on the permeability reduction caused by foam. EXPERIMENTAL PROCEDURES EQUIPMENT AND MATERIALS The experimental apparatus consisted of consolidated and unconsolidated porous media, wet test meters and constant delivery pumps. The porous media consisted of consolidated sandstone cores (6 to 36 in. long), and unconsolidated sand packs (3 to 30 ft long). The consolidated cores had permeabilities of 32 and 1,000 md and porosities of about 20 per cent. The sand packs had permeabilities of 3,500 to 211,000 md and porosities of about 40 per cent. (Throughout this report a term such as "100 md sand" is used. This term means that the porous medium had a dry, nitrogen permeability of 100 md.)Fluids used in the experiments were distilled water, 1 per cent NaCl solution, aqueous solutions of foaming agents, nitrogen gas, air and crude oil. SPEJ P. 295ˆ

Effect of Foam on Permeability of Porous Media to Gas

1964 ◽  
Vol 4 (03) ◽  
pp. 267-274 ◽  
Author(s):  
George G. Bernard ◽  
L.W. Holm
Keyword(s):  
Porous Media ◽  
Oil Recovery ◽  
Gas Flow ◽  
Gas Permeability ◽  
Absolute Permeability ◽  
Displacement Efficiency ◽  
Foaming Agent ◽  
Foaming Agents ◽  
Oil Displacement ◽  
Surface Active

Abstract Laboratory experiments were conducted to determine the effect of foam on gas flow in porous media. Previous studies have indicated that foam may be applicable as a restrictive agent in influencing underground gas flow. Foam was found to be exceedingly effective in reducing the permeability of porous media to gas. Consolidated and unconsolidated sands with specific permeabilities of 100 to 146,000 md had, in the presence of foam, gas permeabilities that were less than 1 per cent of the specific permeability; in many cases the gas permeability was practically zero. Foam reduced the gas permeability of loose sand to a much greater degree than that of a tight sand. For example, the permeability of a 125,000-md sand was reduced to 3 md while the permeability of a 4,000-md sand was reduced to 7 md. This effect should cause, to some degree, a selective plugging of high permeability channels in various oil displacement processes. The presence of oil in a porous medium decreased the effectiveness of foam in reducing gas permeability; apparently oil acts as a foam depressant. However, it was found that certain foaming agents were very effective in reducing permeability even in the presence of oil. Also, continuous injection of other foaming agents increased their effectiveness, when oil was present. The effect of foam on permeability of porous media to gas was studied as a function of foaming agent concentration and injection rate, absolute permeability, total pressure, pressure gradient, length of porous system, brine concentration and time. Introduction The use of surface active agents in flood water to increase the recovery of oil has been studied in the laboratory and in the field for decades, with rather limited success. In recent years a new approach to the problem was proposed. Instead of using an aqueous solution of surfactant as an oil recovery agent, Bond and Holbrook proposed that the oil recovery agent he a mixture of surfactant solution and gas. In their method, a water-soluble surface active agent with foam-producing characteristics is injected into an underground formation as an aqueous slug. This slug is followed by gas to produce a foam within the rock. Foams are defined as "agglomerations of gas bubbles separated from each other by thin liquid films." A foam is fundamentally an unstable system. The foam process for oil recovery has since been studied by other investigators. Fried has shown that foam can displace from porous structures oil that normally is unrecoverable by conventional water or gas drives. This superior oil displacing action is believed to be the result of several factors:foam introduces into the reservoir many resilient interfaces of various sizes and curvatures, which increase the probability that a proper combination of forces for oil displacement will be created;foam has appreciable viscosity which improves mobility ratio and contact efficiency;foam accentuates the trapped gas effect because high gag saturations are possible without producing high gas/oil ratios. Deming studied the effect of various foam properties on the displacement of liquid. He found thathigh foaming ability favors high displacement efficiency;high foam stability is not necessary for high displacement efficiency;displacement efficiency decreases with increase in plasticity of foam anddisplacement efficiency is unaffected by surface tension of foaming agent solution. One of the important aspects of this oil recovery process is the effect of foam on gas permeability. The simultaneous flow of gas and liquid in porous media has been studied by numerous investigators and a large amount of literature exists on the subject. In this previous work, gas and liquid have generally been considered as essentially independent phases, whose flow characteristics are related through the saturation parameter. Foam, however, is a material with properties that are considerably different from those of its components; for example, the viscosity of a foam is greater than either of its components. SPEJ P. 267ˆ

Foam in Porous Media: Characteristics and Potential Applications

1970 ◽  
Vol 10 (04) ◽  
pp. 328-336 ◽  
Author(s):  
S. H. Raza
Keyword(s):  
Porous Medium ◽  
Porous Media ◽  
Oil Recovery ◽  
Flow Behavior ◽  
Foaming Agent ◽  
Reservoir Rocks ◽  
Recovery Processes ◽  
Potential Applications ◽  
Foam In Porous Media

Abstract A laboratory study was made of the variables which affect the generation, propagation, quality und nature of foam produced inside a porous medium. It is shown that foam can be generated and propagated in porous media representative of reservoir rocks at pressure levels ranging from atmospheric to 1,000 psig, and under pressure differentials ranging from 1.0 to 50 psi/ft. The quality of foam depends on the type of foaming agent, the concentration of foaming solution, the physical properties of the porous medium, the pressure level, and the composition and saturation of fluids present. The nature of foam depends upon the type of foaming agent and its concentration in the foaming solution. The study shows that the flow behavior of foam in a porous medium is a complex one which cannot he correctly described in terms of the high apparent viscosity of foam. Also, the concept of relative permeability is not applicable to the flow of foam due to the associative nature of its components. On the basis of the discussed characteristics of foam, several applications of foam are suggested in oil recovery processes.

Reaction Kinetics of In-Situ Combustion: Part 1-Observations

1984 ◽  
Vol 24 (04) ◽  
pp. 399-407 ◽  
Author(s):  
Mohammad Reza Fassihi ◽  
William E. Brigham ◽  
Henry J. Ramey
Keyword(s):  
Porous Medium ◽  
Porous Media ◽  
Reaction Mechanism ◽  
Crude Oil ◽  
Oil Recovery ◽  
Burning Front ◽  
Burning Zone ◽  
Different Temperatures ◽  
Air Compression

Abstract Continuous analysis of produced gases from a small packed bed reactor, at both isothermal and linearly increasing temperatures, has shown that combustion of crude oil in porous media follows several consecutive reactions. Molar carbon dioxide/carbon monoxide (CO2/CO) and apparent hydrogen/carbon (H/C) ratios were used to observe the transition between these reactions at different temperature levels. A new kinetic model for oxidation of crude oil in porous media is presented in Part 2 of this paper (Page 408) Introduction The quantity of fuel consumed and the reaction rate within the burning zone have been studied intensively for two reasons. First, the maximum oil recovery is the difference of the original oil in place (OOIP) at the start of the operation and the oil consumed as fuel. Second, one of the most important factors in the economic evaluation of any in-situ combustion project is the cost of air compression. Excessive fuel deposition causes a slow rate of advance of the burning front and large air compression costs. However, if the fuel concentration is too low, the heat of combustion will not be sufficient to raise the temperature of the rock and the contained fluids to a level of self-sustained combustion. This may lead to combustion failure. Thus, it is necessary to understand the reactions occurring at different temperatures as the combustion front moves in the porous medium. The most crucial and yet least understood zone of insitu combustion oil recovery is the burning front, where temperature reaches a maximum value. The velocity of the burning front is controlled by the chemical reactions involved. However, since crude oil is a mixture of hydrocarbons, it is necessary to consider a global description of the reaction mechanism. Reaction Mechanism The reaction between fuel and oxygen in a forward combustion process is a heterogeneous flow reaction. Injected oxidant gas must pass through the burning zone to make the burning front move. Within the burning zone, four known transport processes occur:oxygen diffuses from the bulk gas stream to the fuel interface; then, perhaps,the oxygen absorbs and reacts with the fuel;then combustion products desorb; andproducts finally transfer into the bulk gas stream. If any of these steps is inherently much slower than the remaining ones, the overall rate will be controlled by that step. Also, the rate of each series of steps must be equal in the steadystate condition. However, there are no useful correlations for computing absorption and desorption of oxygen in a porous medium. Consequently, consideration of these phenomena becomes extremely difficult for even simple reactions. Theoretical expressions for postulated mechanisms often contain 10 or more arbitrary constants. Because of the large number of arbitrary constants, sever-al expressions developed for widely different mechanisms often will match experimental data equally well. In general, the combustion rate, Rc, of crude oil in a porous medium can be described as dCm m nRc = - ------ = kpo2 Cm,............................(1)dt whereCm = instantaneous concentration of fuel, k = rate constant, Po2 = partial pressure of oxygen, andm, n = reaction orders. The reaction constant, k, is often a function of temperature, T, as expressed by k=w exp(– E/RT).......................................(2) where E is the activation energy, w is the Arrhenius constant, and R is the universal gas constant. For heterogeneous reactions, the constant w is a function of the surface area of the rock. Early studies of crude oil oxidation in a porous medium were mostly qualitative. Differential thermal analysis (DTA) was performed on samples of crude oil, and the resulting thermograms represented the thermal history of each sample as it was heated at a uniform rate (usually 18 degrees F/min [10 degrees C/min]) in a constant air flow (usually 277 mL/min [277 cm3/min]). These thermograms indicated the presence of a number of exothermic reactions. Another method of analysis is thermogravimetric analysis (TGA). Here, a sample of crude oil is weighed continuously as it is heated at a constant rate. The resulting curve of weight change vs. time or temperature indicates the occurrence of at least two reactions at different temperatures. SPEJ P. 399^

Mobilization of Crude Oil in Porous Media With Oil-Soluble Surfactant Delivered by Hydrosoluble Micelles

2018 ◽  
Vol 141 (3) ◽  
Author(s):  
Chike G. Ezeh ◽  
Yufei Duan ◽  
Riccardo Rausa ◽  
Kyriakos D. Papadopoulos
Keyword(s):  
Porous Medium ◽  
Porous Media ◽  
Crude Oil ◽  
Oil Recovery ◽  
Sodium Dodecyl ◽  
Packed Bed ◽  
White Pixel ◽  
Soluble Surfactants ◽  
Soluble Surfactant ◽  
Random Porous Medium

In this work, an oil-soluble surfactant was studied to enhance crude oil mobilization in a cryolite-packed miniature bed. The cryolite packed bed provided a transparent, random porous medium for observation at the microscopic level. In the first part of the paper, oil-soluble surfactants, Span 80 and Eni-surfactant (ES), were dissolved directly into the crude oil. The porous medium was imbued with the crude oil (containing the surfactants), and de-ionized water was the flooding phase; in this experiment, the system containing ES had the best performance. Subsequently, sodium dodecyl sulfate (SDS), a hydrosoluble surfactant, was used to solubilize the ES, with the SDS acting as a carrier for the ES to the contaminated porous media. Finally, the SDS/ES micellar solutions were used in oil-removal tests on the packed bed. Grayscale image analysis was used to quantify the oil recovery effectiveness for the flooding experiments by measuring the white pixel percentage in the packed bed images. The SDS/ES flooding mixture had a better performance than the SDS alone.

Surfactant Retention in Berea Sandstone- Effects of Phase Behavior and Temperature

1982 ◽  
Vol 22 (06) ◽  
pp. 962-970 ◽  
Author(s):  
J. Novosad
Keyword(s):  
Porous Media ◽  
Crude Oil ◽  
Phase Behavior ◽  
Oil Recovery ◽  
Liquid Interface ◽  
Divalent Ions ◽  
Surfactant Precipitation ◽  
Wide Range ◽  
Solid Liquid Interface ◽  
Solid Liquid

Novosad, J., SPE, Petroleum Recovery Inst. Abstract Experimental procedures designed to differentiate between surfactant retained in porous media because of adsorption and surfactant retained because Of unfavorable phase behavior are developed and tested with three types of surfactants. Several series of experiments with systematic changes in one variable such as surfactant/cosurfactant ratio, slug size, or temperature are performed, and overall surfactant retention then is interpreted in terms of adsorption and losses caused by unfavorable phase behavior. Introduction Adsorption of surfactants considered for enhanced oil recovery (EOR) applications has been studied extensively in the last few years since it has been shown that it is possible to develop surfactant systems that displace oil from porous media almost completely when used in large quantities. Effective oil recovery by surfactants is not a question of principle but rather a question of economics. Since surfactants are more expensive than crude oil, development of a practical EOR technology depends on how much surfactant can be sacrificed economically while recovering additional crude oil from a reservoir.It was recognized earlier that adsorption may be only one of a number of factors that contribute to total surfactant retention. Other mechanisms may include surfactant entrapment in an immobile oil phase surfactant precipitation by divalent ions, surfactant precipitation caused by a separation of the cosurfactant from the surfactant, and surfactant precipitation resulting from chromatographic separation of different surfactant specks. The principal objective of this work is to evaluate the experimental techniques that can be used for measuring surfactant adsorption and to study experimentally two mechanisms responsible for surfactant retention. Specifically, we try to differentiate between the adsorption of surfactants at the solid/liquid interface and the retention of the surfactants because of trapping in the immobile hydrocarbon phase that remains within the core following a surfactant flood. Measurement of Adsorption at the Solid/Liquid Interface Previous adsorption measurements of surfactants considered for EOR produced adsorption isotherms of unusual shapes and unexpected features. Primarily, an adsorption maximum was observed when total surfactant retention was plotted against the concentration of injected surfactant. Numerous explanations have been offered for these peaks, such as a formation of mixed micelles, the effects of structure-forming and structurebreaking cations, and the precipitation and consequent redissolution of divalent ions. It is difficult to assess which of these effects is responsible for the peaks in a particular situation and their relative importance. However, in view of the number of physicochemical processes taking place simultaneously and the large number of components present in most systems, it seems that we should not expect smooth monotonically increasing isotherms patterned after adsorption isothemes obtained with one pure component and a solvent. Also, it should be realized that most experimental procedures do not yield an amount of surfactant adsorbed but rather a measure of the surface excess.An adsorption isotherm, expressed in terms of the surface excess as a function of an equilibrium surfactant concentration, by definition must contain a maximum if the data are measured over a sufficiently wide range of concentrations. SPEJ P. 962^

Capillary Impregnation of Viscous Fluids in a Multi-Layered Porous Medium

2019 ◽  
Author(s):  
Shabina Ashraf ◽  
Jyoti Phirani
Keyword(s):  
Porous Medium ◽  
Porous Media ◽  
Oil Recovery ◽  
Viscous Fluids ◽  
Spontaneous Imbibition ◽  
Lab On Chip ◽  
Capillary Impregnation ◽  
Relative Placement ◽  
Homogeneous Porous Medium ◽  
Wetting Fluid

Abstract Capillary impregnation of viscous fluids in porous media is useful in diagnostics, design of lab-on-chip devices and enhanced oil recovery. The impregnation of a wetting fluid in a homogeneous porous medium follows Washburn’s diffusive law. The diffusive dynamics predicts that, with the increase in permeability, the rate of spontaneous imbibition of a wetting fluid also increases. As most of the naturally occurring porous media are composed of hydrodynamically interacting layers having different properties, the impregnation in a heterogeneous porous medium is significantly different from a homogeneous porous medium. A Washburn like model has been developed in the past to predict the imbibition behavior in the layers for a hydrodynamically interacting three layered porous medium filled with a non-viscous resident phase. It was observed that the relative placement of the layers impacts the imbibition phenomena significantly. In this work, we develop a quasi one-dimensional lubrication approximation to predict the imbibition dynamics in a hydrodynamically interacting multi-layered porous medium. The generalized model shows that the arrangement of layers strongly affects the saturation of wetting phase in the porous medium, which is crucial for oil recovery and in microfluidic applications.

Analysis of the Influence of Fluid Flow on the Plasticity of Porous Rock Under an Axially Symmetric Punch

1974 ◽  
Vol 14 (03) ◽  
pp. 271-278 ◽  
Author(s):  
Milos Kojic ◽  
J.B. Cheatham
Keyword(s):  
Plastic Deformation ◽  
Porous Medium ◽  
Porous Media ◽  
Fluid Flow ◽  
Pressure Gradient ◽  
Stress Tensor ◽  
Unit Volume ◽  
Fluid Pressure ◽  
The Body ◽  
Axially Symmetric

Introduction A number of problems occur in the fields of drilling and rock mechanics for which consideration must be given to the interaction of fluid flow and rock deformation. Such problems include those of borehole stability, chip removal from under a drill bit, drilling in the presence of a fluid pressure gradient between the drilling fluid and formation fluid, and drilling by use of hydraulic jets. We have recently developed a general theory of the influence of fluid pressure gradients and gravity on the plasticity of porous media. The solution of the problem considered here serves as an example of the application of that theory. The illustrative problem is to determine the load required on a flat problem is to determine the load required on a flat axially symmetric punch for incipient plasticity of the porous medium under the punch when fluid flows through the bottom face of the punch. The rock is assumed to behave as a Coulomb plastic material under the influence of body forces plastic material under the influence of body forces due to fluid pressure gradients and gravity. Numerical methods that have been used by Cox et al. for analyzing axially symmetric plastic deformation in soils with gravity force are applied to the problem considered here. Involved is an iterative process for determining the slip lines. The fluid flow field ‘used for calculating the fluid pressure gradient is based upon the work by Ham pressure gradient is based upon the work by Ham in his study of the potential distribution ahead of the bit in rotary drilling. The effective stresses in the porous rock and the punch force for incipient plasticity are computed in terms of the fluid plasticity are computed in terms of the fluid pressure and the cohesive strength and internal pressure and the cohesive strength and internal friction of the rock. PLASTICITY OF POROUS MEDIA PLASTICITY OF POROUS MEDIA A recently developed general theory of plasticity of porous media under the influence of fluid flow is summarized in this section. The equation of motion for the porous solid for the case of incipient plastic deformation reduces to the following equilibrium equation:(1) where Ts is the partial stress tensor of the solid; Fs is the body force acting on the solid per unit volume of the solid material; P is the interaction force between the solid and the fluid; and is the porosity, which is defined as the ratio of the pore porosity, which is defined as the ratio of the pore volume to the total volume of the solid-fluid mixture. The partial stress tensor Ts can be considered as the effective stress tensor that is used in sod mechanics. With the acceptance of the effective stress principle defined in Ref. 5, the yield function, f, in the following form is satisfied for plastic deformation of the porous medium. plastic deformation of the porous medium.(2) where EP is the plastic strain tensor and K and the work-hardening parameter. From the equation of motion for the fluid, the interaction force P can be expressed in the form(3) where is the inertial force of the fluid per unit volume of the mixture and F is the body force acting on the fluid per unit volume of fluid. For the case of incipient plastic deformation the solid can be considered static (velocities of the solid particles are zero), and the problem of determining particles are zero), and the problem of determining the fluid flow field is the one usually analyzed in petroleum engineering. petroleum engineering. Consider a flow of be fluid such that the inertial forces of the fluid can be neglected and assume that Darcy's law is applicable. SPEJ P. 271

Theory of Plasticity of Porous Media With Fluid Flow

1974 ◽  
Vol 14 (03) ◽  
pp. 263-270 ◽  
Author(s):  
Milos Kojic ◽  
J.B. Cheatham
Keyword(s):  
Plastic Deformation ◽  
Porous Medium ◽  
Porous Media ◽  
Fluid Flow ◽  
General Theory ◽  
Pressure Gradient ◽  
Yield Criterion ◽  
Solid Particles ◽  
Fluid Mixture ◽  
Moving Fluid

Abstract Plastic deformation of a porous medium containing moving fluid is analyzed as a motion of a solid-fluid mixture. The fluid is considered to be Newtonian, and the porous material consists of interconnected pore spaces and of solid particles that can deform pore spaces and of solid particles that can deform elastically. The effective stress principle and a general form of the yield function-including work-hardening characteristics-and general stress-strain relations are applied to describe the plastic deformation of the solid. The system of plastic deformation of the solid. The system of governing equations with the number of unknowns being equal to the number of equations is formed. A possible method of solution of a general problem is described. Some simplification such as problem is described. Some simplification such as the assumptions of quasi-static plastic deformation and incipient plastic deformation with the application of Darcy's law for the fluid flow are discussed. To illustrate an application of the theory, the problem of incipient plane plastic deformation of a Coulomb material is presented. Introduction The motion of fluid through a porous medium and the deformation of a porous medium containing fluid have been the subjects of many investigations. For problems concerning fluid flow through porous media in petroleum and civil engineering literature, the porous material is usually considered undeformable and Darcy's law is taken as the governing relation between the velocity and the pressure of the fluid. pressure of the fluid. Most of the effort concerning fluidization of porous media has been experimental; here the task porous media has been experimental; here the task is to find the critical pressure gradient or the critical velocity of the fluid that will cause fluidization. Only the one-dimensional equilibrium equation, which relates Ne pressure gradient of the fluid and densities of solid and fluid, has been analyzed in most fluidization studies. Recently, a more general theoretical approach has been taken and equations of motion of fluid and solid have been established. Some of the results of this theory are used in the present study. Previous investigations of the deformation of porous media containing fluid have been both porous media containing fluid have been both empirical and theoretical. In the domain of elastic deformation much of the published material has dealt with experimental work aimed at finding the relation between a change in fluid pressure and stresses and deformation of the solid phase. A general theory of elasticity of porous media containing moving fluid was established by Biot. However, that theory is approximate since Darcy's law is considered as a governing relation for the fluid, and the change of permeability with the deformation of the solid is neglected. A simplification of this theory was presented by Lubinski. Experimental work has been carried out in the domain of plastic deformation of porous media containing fluid. The effective stress principle has been established as a result of experiments using saturated sand and porous rocks with various pore pressures (fluid is static in these experiments. pressures (fluid is static in these experiments. This principle, which is considered as a fundamental principle in soil mechanics, states that the pore principle in soil mechanics, states that the pore pressure does not affect the yield criterion of the pressure does not affect the yield criterion of the solid. In other words, the yield condition of the solid depends only on stresses transmitted among the solid particles. The influence of fluid flow on plasticity of porous media was indicated by Lambe and Whitman porous media was indicated by Lambe and Whitman in the analysis of stability of an infinite slope of a soil. In the equilibrium equation of a so-called "free body" a term equal to the negative pressure gradient is added. There is no general theory for plasticity of porous media containing moving fluid. plasticity of porous media containing moving fluid. GENERAL THEORY Consider the motion of a solid-fluid mixture and suppose that the motion of the solid is a plastic deformation. Then the problem reduces to the following: define the motion of a solid-fluid mixture so that the yield criterion of the solid is satisfied. The mechanical model can be described as follows. 1. The system comprises one fluid and one should constituent. SPEJ P. 263

Oscillatory forcing of flow through porous media. Part 2. Unsteady flow

2002 ◽  
Vol 465 ◽  
pp. 237-260 ◽  
Author(s):  
D. R. GRAHAM ◽  
J. J. L. HIGDON
Keyword(s):  
Porous Medium ◽  
Porous Media ◽  
Pressure Gradient ◽  
Flow Rate ◽  
Flow Through Porous Media ◽  
Mean Flow ◽  
Two Fluids ◽  
Mean Pressure ◽  
Flow Through ◽  
The Mean

Numerical computations are employed to study the phenomenon of oscillatory forcing of flow through porous media. The Galerkin finite element method is used to solve the time-dependent Navier–Stokes equations to determine the unsteady velocity field and the mean flow rate subject to the combined action of a mean pressure gradient and an oscillatory body force. With strong forcing in the form of sinusoidal oscillations, the mean flow rate may be reduced to 40% of its unforced steady-state value. The effectiveness of the oscillatory forcing is a strong function of the dimensionless forcing level, which is inversely proportional to the square of the fluid viscosity. For a porous medium occupied by two fluids with disparate viscosities, oscillatory forcing may be used to reduce the flow rate of the less viscous fluid, with negligible effect on the more viscous fluid. The temporal waveform of the oscillatory forcing function has a significant impact on the effectiveness of this technique. A spike/plateau waveform is found to be much more efficient than a simple sinusoidal profile. With strong forcing, the spike waveform can induce a mean axial flow in the absence of a mean pressure gradient. In the presence of a mean pressure gradient, the spike waveform may be employed to reverse the direction of flow and drive a fluid against the direction of the mean pressure gradient. Owing to the viscosity dependence of the dimensionless forcing level, this mechanism may be employed as an oscillatory filter to separate two fluids of different viscosities, driving them in opposite directions in the porous medium. Possible applications of these mechanisms in enhanced oil recovery processes are discussed.

scholarly journals Investigation of clogging in porous media induced by microorganisms using a microfluidic application

2021 ◽  
Author(s):  
Calvin Lumban Gaol ◽  
Leonhard Ganzer ◽  
Soujatya Mukherjee ◽  
Hakan Alkan
Keyword(s):  
Porous Medium ◽  
Porous Media ◽  
Hydrogen Storage ◽  
Enhanced Oil Recovery ◽  
Oil Recovery ◽  
Aquifer Storage And Recovery ◽  
Aquifer Storage ◽  
Medium Permeability ◽  
Underground Hydrogen Storage

The presence of microorganisms could alter the porous medium permeability, which is vital for several applications, including aquifer storage and recovery (ASR), enhanced oil recovery (EOR) and underground hydrogen storage.

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