Large scale wettability quantification in porous media using tracers

Tracers are widely used to study physical phenomena taking place inside the porous medium such as hydrodynamics of the reactor by residence time distribution, and characterizing the oil reservoirs for heterogeneity and residual oil saturation. In this work, we use tracer techniques to characterize oil phase tracers to quantify the wettability of a fluid in a multi-phase flow in a porous medium. The wetting fluid will have more contact area with the sediments. The quantification of contact area of a fluid with sediments during flow will give us insights into the wettability and wettability alteration. A two tracer method is used to quantify the wetted area by one fluid in the porous medium. We first find the adsorption characteristics of the tracers for non-aqueous-phase tracers on the sediments. Subsequently flow experiments are performed to conduct residence time distribution (RTD) analysis using single phase flow. The adsorption characteristics during flow are identified for various flow rates. The difference in RTD curves of the two tracers of a phase is used to estimate the area in contact with the fluids with the sediment surface.