FLOW OF DILUTE, STABLE EMULSIONS IN POROUS MEDIA

Emulsion flow in porous media has been studied to design filters for waste water renovation processes and to model newly developed enhanced oil recovery processes. In general, the emulsion employed in an oil recovery process is highly stable. Also, because the underground media have relatively low permeabilities and the emulsion drop sizes may overlap the pore sizes, larger permeability reduction occurs. This work establishes the flow mechanism which brings about the permeability reduction and models this mechanism mathematically.; The discussion is divided into five chapters. In Chapter I, the flow mechanism is established experimentally. We find that permeability reduction is caused by a drop-capturing mechanism similar to that found for solid particles in deep-bed filtration.; In Chapter II, we present a simplified filtration model describing the flow of stable, dilute emulsions in unconsolidated media. In the model emulsion drops are captured in pores by straining and interception, and thereby reduce the permeability.; In Chapter III, the velocity effect in emulsion flow through porous media is examined, again from the viewpoint of deep-bed filtration. Straining and interception controlled capture are considered separately. We find that at low capillary numbers (i.e. 10('-6) to 10('-4)), pseudo thinning of the fluid occurs only when surface capture exists in the secondary minimum of the interparticle potential. When the capillary number is on the order of 10('-3) or above, psuedo-thinning occurs due to drops squeezing through pores. Drop breakup does not occur until very high capillary numbers of around unity.; In Chapter IV, the drop size distribution effect on the emulsion flow behavior is examined, based on the deep-bed filtration theory. The model employs competition for capture sites until the smaller particles establish a steady state. Computations show that a polydisperse suspension can be approximated as monodisperse when the column is short, and when capture occurs only by interception.; In Chapter V, pore size distribution measurement by the centrifugal method is discussed. A new parameter estimation method is developed for replacing the existing double differentiation method.