Evaluation of the Induced Oil Remobilization Through High and Low Salinity Waterflooding in a Porous System via X-ray Microtomography

Abstract

The X-ray microtomography was used to visualize and characterize the remobilization oil process inside the porous system of a carbonate rock sample. After being saturated with a brine solution, dodecane oil was injected into the porous media, initially a predominant water-wet system. After an aging process is performed, the system became mixed-wet. The remobilization was induced by the injection of two KI (Potassium Iodide) brine solutions, a high salinity solution injection (1.5 M) followed by a low one (0.3 M). The intention was to achieve, besides the immiscible displacement process, oil remobilization due to the modification of interfacial properties of fluids and wettability caused by low salinity of the injected brine. It was observed that the low salinity brine was capable of shifting the oil inside the porous medium and reduce the residual oil saturation.