Immiscible displacement

The issues of selection of the spatial wavelength and the deterministic character of the fine scale features of the microstructure are closely related to similar questions in nonlinear transitions in a host of other physical systems, such as macroscopic models of immiscible displacement in porous media - - the Hele Shaw Problem (15) - and flow transitions in fluid mechanical systems (16). 

Gollany HT, Bloom PR, Schumacher TE. Rhizosphere soil-water collection by immiscible displacement-centrifugation technique. Plant Soil 1997 188 59-64. 

We discnss network models fnrther in Sect. 11.4, in the context of immiscible displacements. 

Lenormand R, Touboul E, Zarcone C (1988), Numerical models and experiments on immiscible displacement in porous media. J ITuid Mech 189 165-187 Levy M, Berkowitz B (2003) Measurement and analysis of non-Fickian dispersion in heterogeneous porous media. J Contam Hydrol 64 203-226... 

Wilkinson D (1986) Percolation effects in immiscible displacement. Phys Rev A 34 1380-1391 Wilkinson D, WiUemsen JE (1983) Invasion percolation A new form of percolation theory. J Phys A 34 1380-1391... 

Thomson NR, Graham DN, Farquhar GJ (1992) One-dimensional immiscible displacement experiments. J Contam Hydrol 10 197-223... 

Results of Immiscible Displacement Tests. The results of the tests show that immiscible carbon dioxide flooding followed by waterflooding is effective in increasing the oil recovered from a core. The oil recovered by a conventional waterflood was equal to about 30.4% of a pore volume, PV. Immiscible carbon dioxide flooding increased the recovery to a total of 50.5% PV. The addition of a mobility control agent increased the recovery further to 58.3% PV this amounts to 39% additional tertiary oil due to the effectiveness of the mobility control in the carbon dioxide immiscible process. 

In the two-phase region, the type II(+) system has an oil-rich micellar phase in equilibrium with an excess brine phase. Surfactant is found almost exclusively in the oil-rich phase, and the concentration of surfactant in that phase can greatly exceed the concentration of surfactant in the injected chemical slug. In the type II(+) environment, the micellar phase remains miscible with the oil but is immiscible with the brine. Oil continues to be recovered by a misciblelike process. The opposite occurs if the phase environment is type II(-). The brine-rich micellar phase is immiscible with the oil phase, and oil recovery is by low IFT immiscible displacement. 

Nelson and Pope concluded that chemical flood design should be such as to maintain as much surfactant as possible in the type III phase environment. This condition can be accomplished by designing the micellar fluid such that the initial phase environment of the immiscible displacement is type II(+). A negative salinity gradient is imposed, and it moves the phase environment to type III and, eventually, to II(-). 

Lenormand, R. Touboul, E. Zarcone, C. Numerical models and experiments on immiscible displacements in porous media. J. Fluid Mech. 1988, 189 (7), 165-187. 

Because mercury is nonwetting, mercury porosimetry is used to obtain capillary pressure curves during injection (see section on Immiscible Displacement ). This technique allows estimates of pore-size distribution to be made. 

One phase displacing another from a porous medium is termed immiscible displacement. The process is usually inefficient from the standpoint of how much of the original phase can be displaced, which is the reason that large amounts of crude oil remain unrecovered in abandoned reservoirs. 

Immiscible displacements rarely proceed as uniform fronts. The most well-documented instability is viscous fingering, which occurs due to an unfavorable mobility ratio, meaning... 

Examples of miscible displacement are the intrusion of saltwater into fresh groundwater or a step change in feed composition in a chemical reactor. In one sense, miscible displacements are simpler processes than immiscible displacements because issues such as interfacial behavior and phase trapping are not relevant. However, they are complicated by hydrodynamic dispersion (which tends to smear the displacement front), and they are subject to similar viscous instabilities as those described earlier. 

Researchers have used physical models of porous media to study flow problems for many years. For example, the Hele-Shaw cell appeared in the late 1800s (Sahimi, 1993). The first reported use of such models for two-phase systems is attributed to Chatenever and Calhoun (1952), who used Lucite and glass bead packs to view immiscible displacement of brine and crude oil (Buckley, 1991). Subsequently, etched and photo-etched glass were used to construct physical models. The use of molded resins for model construction was introduced in the 1970s (Buck-ley, 1991). 

The linear displacement of fluid through porous solid material by another fluid that is completely miscible in the first can have an efficiency approaching 100%. This linear displacement is in contrast to immiscible displacement (such as of oil by water) in which a significant fraction of the original fluid remains trapped in the pores. Thus, dense C02 has an inherent advantage over immiscible fluids, like water, in the recovery efficiencies that are possible with its use. 

More sophisticated one-dimensional models have included deadend pores, ink-bottle pores, pockets or turner structures, and also, periodically constricted tubes. Two-dimensional and three-dimensional network models have also been developed. The first proposal for a two-dimensional network model was given by Fatt (37, 38). Whereas Fatt primarily dealt with immiscible displacement, Simon and Kelsey (39) used a two-dimensional network model for the simulation of miscible displacement. The first three-dimensional network model is due to Irmay (40). Subsequently, the three-dimensional network model or percolation theory for porous medium has received much attention... 

Thiele, M. Blunt, M. Orr Jr., F. (1995A) Modeling flow in heterogeneous media using stream-tubes, I - Miscible and immiscible displacements. In Situ 19(3), 299-339. 

Secondary production Production of oil when gas, water, or both are injected into the formation and the injected fluid immiscibly displaces the oil. 

Handy, L.L. and Datta, P. Fluid Distribution During Immiscible Displacements in Porous Med/a", Trans. AIME (1966) 237, 261. 

Peters, E.J., and Flock, D.L. The Onset of Instability During Two-Phase Immiscible Displacements in Porous Media", SPE J. (April 1981) 249-258. 

Aqueous immiscible flow, or immiscible displacement, irrvolves the simultaneous flow of two or more immiscible fluids in the porous medium. Since the fluids are immiscible, the interfacial tension between the two fluids is not zero, and a distinct fluid-fluid interface separates the flirids. 

YOKOYAMA, and LAKE, L. W., The Effects of Capillary Pressure on Immiscible Displacements in Stratified Permeable Media, SPE 10109, presented at 56th Annual Fall Conference of SPE, San Antonio, Texas,... 

Kinetic surface properties such as interfacial viscosity have been suggested as perhaps playing a significant role in mobilization (14,15). Based on the model it has been possible to assess the very minor role which this property can assume in aiding mobilization of residuals by immiscible displacement. 

THE INFLUENCE OF INTERFACIAL PROPERTIES ON IMMISCIBLE DISPLACEMENT BEHAVIOR... 

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