An experimental investigation of multi-phase flow and the effect of fracture on enhanced oil recovery in the porous medium

Large amounts of oil remain in the reservoir in conventional oil production. Strategies for extracting residual oil in the reservoir are called enhanced oil recovery(EOR). One of the usual methods of EOR is the WAG injection. The study of this injection method in a two-dimensional porous medium has been less considered. In this study, two porous mediums are made using a 3D printer. One is simple(S), and the other has a horizontal fracture(F). Nitrogen gas and water have been used in three different scenarios, in the form of a single injection of gas, a single injection of water, and the alternating injection of both, in order to increase the oil recovery. Then, by image processing, the recovery rate of each injection scenario is calculated. This study shows that the WAG injection in S sweeps about 55% of the media, which is more than 6 times the injection of gas alone and more than 2.5 times the injection of water alone. WAG injections in the F also sweep about 38% of the media, which is more than 2.5 times than the other injections scenario. The reason for the difference in recovery rate between the two media in WAG injection is the negative impact of fracture. Also, the difference between WAG injection and single injections can be found in the pressure gradian diagram.