Modeling and simulation of microbial enhanced oil recovery including interfacial area

TL;DR

This paper develops a novel 2D model for microbial enhanced oil recovery that incorporates interfacial area effects, improving understanding of bacteria, surfactants, and oil-water interactions to optimize recovery strategies.

Contribution

The paper introduces the first model including interfacial area in MEOR, accounting for IFA effects on hysteresis, bacteria migration, and surfactant production, with a robust numerical scheme.

Findings

Inclusion of IFA affects oil recovery profiles.

The model demonstrates improved stability and efficiency.

Simulations highlight the impact of IFA on surfactant effectiveness.

Abstract

The focus of this paper is the derivation of a non-standard model for microbial enhanced oil recovery (MEOR) that includes the interfacial area (IFA) between the oil and water. We consider the continuity equations for water and oil, a balance equation for the oil-water interface and advective-dispersive transport equations for bacteria, nutrients and surfactants. Surfactants lower the interfacial tension (IFT), which improves the oil recovery. Therefore, we include in the model parameterizations of the IFT reduction and residual oil saturation as a function of the surfactant concentration. We consider for the first time in context of MEOR, the role of IFA in enhanced oil recovery (EOR). The motivation to include the IFA in the model is to reduce the hysteresis in the capillary pressure relationship, include the effects of observed bacteria migration towards the oil-water interface and biological production of surfactants at the oil-water interface. An efficient and robust linearization scheme was implemented, in which we use an implicit scheme that considers a linear approximation of the capillary pressure gradient, resulting in an efficient and stable scheme. A comprehensive, 2D implementation based on two-point flux approximation (TPFA) has been achieved. Illustrative numerical simulations are presented. We give an explanation of the differences in the oil recovery profiles obtained when we consider the IFA and MEOR effects. The model can also be used to design new experiments in order to gain a better understanding and optimization of MEOR.