Investigation of waterflooding under the effect of electrical potential gradient

Aggour, M.A. and Muhammadain, A.M., 1992. Investigation of waterflooding under the effect of electrical potential gradient. J. Pet. Sci. Eng., 7: 319-327. An experimental study has been conducted to investigate the effect of electrical potential gradient on oil recovery, water, production and water-oil ratio during water flooding. The experiments were performed using a linear model packed with 30/40 mesh sand. Oil of 28.7 degrees API gravity and water having 30,000 ppm NaCl were used in the experiments. Direct electrical potential gradients ranging from 0.5 to 7.5 V/cm were examined. The potential gradient was applied across the oil-water bearing formation such that the injection end was the cathode and the production end was the anode. It was found that the application of the direct electrical potential gradient results in increasing the oil recovery and reducing water production and water-oil ratio (WOR). Further, these effects were directly proportional to the increase in the applied electrical potential difference, and were only appreciable after water breakthrough.