An analytical model for leaching and transport of alkylphenols from crude oil in porous media

Abstract

Formed along with petroleum, stable in reservoir conditions, able to partition between oil/water phase, alkylphenol compounds can be used as natural indicators (tracers) to exploit the information about oil saturation and contribution to production wells. This paper presents an one-dimensional analytical model for leaching and transport of alkylphenols from oil phase to water phase during waterflooding. The obtained solution of advective-dispersive equation expresses the concentration of alkylphenols decreasing over time across waterflooding. The experiments of oil displacement by waterflooding through the packed column gave the good agreement between experimental data and analytical data. The analytical model also showed the obvious relation of decrease rate of alkylphenol concentration with distribution coefficient, oil saturation and velocity of water phase, but insignificant relation with diffusion coefficient of alkylphenols. The matching also showed the disadvantage of used method of static phasic contact in distribution coefficient measurement which relates to the equilibrium establishment of different alkylphenols. Obviously, the analytical solution obtained from advective-dispersive equation for leaching and transport of alkylphenols from oil phase to water phase is an important base for further studies of using alkylphenols as the natural indicators (tracers) of residual oil saturation in oil production.