Effects of ultrasonic waves on water imbibition into oil-wet carbonate reservoirs (a case study)

In this study, imbibition tests with and without ultrasonic radiation were performed on limestone samples obtained from the Asmari formation, which is the main Iranian oil reservoirs. The test results have shown a significant increase in the oil recovery with ultrasonic radiation. Reducing the interfacial tension (IFT) and thus reducing the capillary holding force of oil is considered a possible mechanism for increasing oil recovery from oil-wet rock. The capillary pressure curve shows that a relatively large increase in the oil recovery from oil-wet samples will occur if the IFT decreases and the gravity force becomes a dominant force.