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Abstract：
The complex and variable structure of subsurface oil reservoirs as well as the small pore throat size of reservoirs make it extremely important to investigate the effect of oil-water-rock interactions for enhancing oil recovery. In this paper, the powder wettability of oil sand with different polar solvents was investigated using the improved Washburn capillary rise method, and the surface free energy of oil sand was calculated in combination with the OWRK method. In addition, the wettability of anionic surfactants HABS and PS solutions on the surface of oil sand was determined, and it showed that their wetting rates showed different trends after CMC (critical micelle concentration). The C×cosθ value of HABS decreased significantly with increasing concentration, whereas PS showed little changes. This may be related to the aggregate structure formed by HABS on the oil sand surface. Meanwhile, the interfacial free energy between crude oil and oil sand was obtained by crude oil-to-oil sand wetting experiments, and found that the wetting rate of crude oil to oil sand was much lower than that of solvents and surfactants. In combination with the above results and the oil-water interfacial tension (IFT), the oil-water-rock three-phase contact angle and the work of adhesion between the crude oil and the solid were obtained by Young\'s equation. From the three-phase contact angle results, it can be found that the contact angle values of both HABS and PS are obviously higher than that of the simulated water, and both HABS and PS have the ability to significantly reduce the work of adhesion, which shows a strong ability to strip the oil film on the surface of the solid. The research results of this paper are helpful to understand the oil displacement mechanism of chemical flooding in reservoir pores, which is of great significance for improving oil recovery.
摘要：
地下油藏的复杂多变的结构以及油藏的小孔喉尺寸使得研究油-水-岩相互作用对提高采收率的影响极为重要。在本文中,用改进的Washburn毛细管上升法研究了不同极性溶剂对油砂的粉末润湿性,并结合OWRK方法计算了油砂的表面自由能。此外,测定了阴离子表面活性剂HABS和PS溶液在油砂表面的润湿性,结果表明，它们的润湿速率在CMC（临界胶束浓度）之后表现出不同的趋势。HABS的C×cosθ值随着浓度的增加而显著降低,而PS显示变化不大。这可能与HABS在油砂表面形成的聚集体结构有关。同时,通过原油对油砂的润湿实验，得到了原油与油砂之间的界面自由能，发现原油对油砂的润湿速率远低于溶剂和表面活性剂。结合上述结果和油水界面张力（IFT），通过杨氏方程获得了油-水-岩三相接触角和原油与固体之间的粘附功。从三相接触角结果来看，发现HABS和PS的接触角值明显高于模拟水，并且HABS和PS都具有显着减少粘附功的能力，具有很强的剥离固体表面油膜的能力。本文的研究成果有助于理解储层孔隙化学驱的驱油机理,这对提高石油采收率具有重要意义。
