Uncertainty in WAG Injection Modelling using Empirical methods and Three-Phase Pore-Network Modeling with Rock Heterogeneity Effect

Abstract

Abstract-The demand for fossil fuel for instance, oil and gas has been dramatic in recent decades. Therefore, many oil and gas companies are attempting to find out new technics for enhancing oil recovery for example, secondary and tertiary methods. Indeed, in recent years the interest in water alternating gas (WAG) has been increased as tertiary recovery method. Moreover, this method has been applied successfully in several fields around the world. In fact, the (WAG) injection method results in three-phase flow zones. Therefore, it is important to understand and well describing the multi-phase flow properties. This study investigated the uncertainty in multi-phase flow between pore-scale network modelling and empirical methods. Network models are being used as alternative for empirical methods to describe the multi-phase flow properties, since the former are physically-based tools which integrate the relevant pore-scale mechanisms while the latter often have little physical basis. The reservoir simulation has been employed to study the effect of rock heterogeneity on the absolute oil recovery obtained by empirical methods and pore network model during WAG injection in heterogeneous reservoirs. The results showed that rock heterogeneity could increase the three phase flow uncertainty between empirical methods and pore network modelling. Moreover; the investigation showed significant effect of rock heterogeneity (different relative permeability models) on overall WAG performance.