On The Numerical Modeling For Surfactant Flooding Of Oil Reservoirs.

Abstract

A surfactant flood model for a three-component (petroleum, water, surfactant),
two-phase (aqueous, oleic) system is presented and analyzed. It is ruled by a system of nonlinear,
partial, differential equations: the continuity equation for the transport of each
component, Darcy’s equation for the flow of each phase and algebraic equations. This system
is numerically solved in the one-dimensional case by finite differences using a procedure
implicit in pressure and explicit in concentrations. The simulator is fed with the physical
properties that are concentration dependent functions– such as phase behavior, interfacial
tension, relative permeabilities, residual saturations, phase viscosities, adsorption and others.
Measurement of these properties is difficult and sometimes hampered by couplings. That is
why the main issue in simulation of surfactant flooding is the unavailability of data.
Therefore, the purpose of this paper is twofold. First, to describe with detail those phase
properties and their relationships. We have found that the partition of the three-components
between the two-phases determines all other physical property data and hence the oil
recovery. Second, to present a sensitivity analysis of the influence of that partition on
cumulative oil recovered as a function of time.