The local equilibrium assumption is a well-known simplification to describe instantaneous processes, with widely different time scales when compared to flow time scales. In this proposed work, we employ this assumption for modeling both volumetric and surface processes. This work aims to model physical and chemical processes, which can be broadly categorized as equilibrium and kinetic type. This classification differs from chemical equilibrium and kinetics, which strictly refer to ionic interactions. We propose to develop more general equilibrium and kinetic models, which will account for weak physical interactions such as van der Waals interactions in addition to the ionic interactions. This will allow us to predict wettability alteration due to adsorption/desorption of both polar and non-polar molecules. The model developments will be implemented in IPARS (Integrated Parallel Accurate Reservoir Simulator) under the TRCHEM reactive chemistry module. Application areas include hydrocarbon recovery prediction from low salinity water floods, reservoir characterization and diagnostic techniques using nano-particle injection engineered to mimic specific chemical species behavior.

Figure. Nanoparticle transport in a curvilinear reservoir: Nanoparticle slug injection with adsorption (left) and multiple nanoparticle slug injection (right) without adsorption.