声波振动与岩石表面润湿性

SOUND VIBRATION ON WETTABILITY OF ROCK SURFACE

通过水与岩石表面接触角的测定、声被驱油实验和理论分析，研究考察了声波振动对原油─岩石、水─岩石界面特性的影响，从界面化学角度对岩石表面的润湿性和声波驱油机理进行了探索。结果表明：经原油浸泡后，由于原油中极性化合物（胶质、沥青质等）在岩石表面的吸附，岩石表面由水相润湿为主转变为油相润湿为主；无论岩石表面以水相润湿为主还是油相润湿为主，在水浸泡过程中，声波振动可促进其表面亲油性减弱和亲水性增强，毛细管阻力降低；伴随着岩石表面润湿性的改变，原油对岩石表面的粘附功明显降低；减弱了原油与岩石表面间的粘滞力，使原油更易于从岩石表面上剥离，提高原油采收率；岩石的渗透率越低，声波振动作用越显著。

The influence of sound action on interfacial properties of crude oil/rock and water/rock interfaces has been investigated bythe measurement of the contact angle of water on rock surface,flooding under sound action and theoretical analysis. The wettability of rock surface and the mechanism of water flooding under sound action have also been studied based on the theory of interfacial surface chemistry. The result shows that the wettability of rock surface was changed from water wettalbe into oil wettabledue to the adsorption of polar components,such as asphaltene and resin fractions,after the rock was saturated with crude oil. Theoil wettability of the rock surface could be decreased and the water wettability of the rock surface could be increased by sound vibration while the rock was immersed in water. The affection of the sound action on rock wettability works for both oil wettableand water wettable rocks. Therefore, the capillary resistance could be decreased. As the wettability of the rock surface waschanged,the cohesion work of crude oil on the surface of rock was reduced obviously,so that the viscous force between the crudeoil and the rock surface was reduced and the crude oil was easily removed from the rock surface,which made the oil recovery rateincreased. The lower the permeability of the rock,the higher the oil recovery rate of water flooding was increased under sound vibration.