Development and Testing of Electrically Enhanced Oil Recovery (EEOR) Utility Model for Heavy Oil Reservoir

This study explores the effect of direct current (DC) electrical treatment on the effective permeability of porous media. The whole treatment program lasted 6430 min (107 h). Heavy oil and brine-saturated cores were subjected to a series of four treatments using different voltages (40 V, 10 V, 5 V, and 35 V) using the same Berea sandstone samples for all tests. There were noticeable changes in effective permeability at each step. Effective permeability decreased the most during the first treatment at 40 V. A decrease in voltage to 10 V allowed effective permeability to increase to a value closer to the untreated state. Effective permeability continued to increase to the highest value of the entire test at the 5 V treatment. The final treatment was at 35 V. Even though the data provide evidence of changes in effective permeability at different voltages, it would be unwise to draw conclusions based on rank-order voltage tests. For one thing, all samples had been exposed to previous treatments, and therefore it is difficult to discern if the observed changes in permeability are due to an individual treatment. The conditioning of the samples could also explain the changes. The data provide evidence of permeability changes over a fixed sequence of treatments; the data do not show the ranking of voltages, nor does it show the optimal voltage. There are some other things we need to be clear about regarding boundaries. Because current versus time data were not broken down by phase, energy consumption and efficiency figures could not be calculated. Pore-scale processes were not observed, and field-scale oil recovery was not measured. As such, the results are controlled laboratory observations, a proof of concept rather than a production-ready outcome. The goal of the work is to monitor the change in permeability for the 40 → 10 → 5 → 35 V sequence for a duration of 6430 min. Of all the methods, EEOR is the one that has not been deeply studied and applied, which indicates the presence of considerable unexplored potential within this promising approach. Field applications of electrical stimulation have been reported in several regions. Although numerous publications and studies have shed light on electrostimulation enhanced oil recovery (EOR), the field remains ripe for further exploration, owing to its inherent complexity and multidisciplinary nature. Many aspects of the technology remain far from fully understood. For example, the precise mechanisms of how varying types and degrees of electrical stimulation impact different types of reservoir rocks and fluid characteristics are not yet fully delineated. This proof-of-concept study documents effective permeability measurements during a fixed sequence of constant DC voltage phases. It does not separate voltage from treatment history, determine an energy optimum, or establish oil recovery performance. It is important to understand how reservoir heterogeneity affects the effectiveness of electrostimulation. In addition, optimizing the energy usage of the process to maximize oil recovery while minimizing environmental and economic costs is a vast area for potential study. Moreover, the development and refinement of real-time data analytics and control systems, like the proposed control panel, to better manage and adapt electrostimulation processes based on reservoir responses is another promising research direction. Electrostimulation is a promising area of EOR technology, and there is still much to explore. Further research will help us better understand the underlying mechanisms and develop this technology for more effective oil recovery.