Simulation of oil-water flow with permeability variation due to incompatible brine salinities

Abstract EN

A numerical simulator (two phase, one dimensional, oil-water fluid flow model) was developed which takes into consideration the difference between the salinities of the injected and saturating brines.

The mathematical model encompassing the above phenomena was formulated from oil-water flow equations coupled with the convective-diffusive equation which describes the movement of salt in the aqueous phase.

A finite difference solution was applied to compute pressures and satura-tions given the injected water salinity and a few rock parameters determined by laboratory experiments.

The mathematical model calculations were carried out to simulate laboratory displacement runs.

The predicted pressure drop was accurate when compared to the experimental pressure drop across the cores with a maximum error of 1.39%.

This error, however, increases to 15.30% when the computed relative per-meabilities were compared to those calculated from experimental data using the JBN method.

This was attributed to inaccuracies inherent to the JBN method when flow conditions do not satisfy Buckley-Leverett theory assumptions.

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