Evaluation of the dynamic's adsorption of polar components during the wettability restoration of carbonate rocks from Brazilian pre-salt reservoirs and their preservation for relative permeability tests

In the rock aging process for relative permeability assessment, it is essential to understand theadsorption dynamics of polar components over time, as these are the main molecules responsible forrendering the wetting properties of the rock. In this study, two carbonate rock facies representative ofBrazilian Pre-salt reservoirs were evaluated. Wettability restoration was performed using two methods:dynamic and static aging. In the dynamic method, 2.0 pore volumes (PV) of dead oil were injected 13 timesat a flow rate of 0.1 mL/min, with effluent collection every 0.25 PV. For static aging, aliquots were collectedduring the initial days and subsequently every seven days, totaling a 30-day aging period. To assess theadsorption dynamics of polar components, Total Acid Number (TAN) and Total Base Number (TBN) valueswere determined for each facies under each aging condition. The results demonstrated variations in theadsorption behavior of both polar components throughout the injections and immersion periods in eachaging process, enabling correlation with the time required to restore the original wettability.