Investigation of the Feasibility of Crude Oil Viscosity Change under an Applied Electrical Field in Porous Media and its Significance for Transport Phenomena

The electrically enhanced oil recovery (EEOR) method takes advantage of electrokinetic phenomena. One of the hypothesized underlying mechanisms involved in this method is the reduction of crude oil viscosity due to an applied electrical field and therefore an increase in the oil mobility. This study investigates the feasibility of oil viscosity change due to an applied electrical field and its importance in transport phenomena during oil recovery using experimental and numerical tools. The physical experiment simulated the application of an applied electrical field to a synthetic formation in a small-scale test cell. The results of the physical experiment indicated a slight reduction in the oil viscosity at the center region of the test cell. To examine the effect of the change in oil viscosity on transport, a numerical experiment was performed. The data from this experiment and from other experimental and field applications available in the literature were used to linearly interpolate the value of the oil viscosity with time. The results of the numerical experiments indicated that incorporating the changes in the oil viscosity leads to a considerable increase in the cumulative oil production, whose magnitude depends on the magnitude of viscosity change due to the electrical field application.