Production of crude oil from a matured oil reservoir is challenging due to the low recovery factor. Hybrid methods have demonstrated potential in oil recovery from the matured crude oil reservoir. In recent years, the low salinity water with chemicals (viz., surfactant, polymer) and nanoparticles have brought the attention of the researchers due to their ability in altering the interfacial properties of the rock-oil-water systems favorable for crude oil recovery. The current interest by industries in injection fluid (i.e., low salinity water injection) has prompted the invention of a hybrid oil recovery agent for matured crude oil reservoirs. In the current study, a novel silica-based hybrid nanofluids (NFs) of variable silica nanoparticles (NPs) concentration in low salinity seawater with anionic surfactant (AOT: dioctyl sodium sulfosuccinate) and polymer (PVP–K30: polyvinylpyrrolidone) (sometimes referred to as SMART LowSal) are used as an injection fluid in a sand-pack reactor. Oil recovery from oil saturated sand-pack reactor is observed to enhance due to NFs (hybrid) injection after secondary recovery. The characteristic study of relative permeability curves discloses that sand surface was initially water-wet and converted to strongly water-wet in the presence of NFs. A nuclear magnetic resonance (¹H NMR) study reveals that adsorption of the chemical appeared on the sand surfaces, which could be the reason for wettability alteration, and thereby enhanced oil recovery. Similarly, the scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDXA) of the sand samples before and after injection disclosed desorption of hydrocarbon from the sand surfaces after NFs injection. An additional 5–10% oil recovery is achieved after chemical flooding due to the injection of NFs. Adsorption isotherm study well agreed with the monolayer adsorption of surfactant on the sand surface.

由于采收率低，从成熟油藏生产原油具有挑战性。混合方法已经证明了从成熟原油储层中采油的潜力。近年来，含有化学物质（即表面活性剂、聚合物）和纳米颗粒的低盐度水因其能够改变有利于原油采收的岩-油-水体系界面特性而引起了研究人员的关注。工业界目前对注入流体（即低盐度注水）的兴趣促使发明了一种用于成熟原油储层的混合采油剂。在目前的研究中，一种新型的二氧化硅基混合纳米流体 (NFs)，在低盐度海水中具有可变二氧化硅纳米粒子 (NPs) 浓度，并带有阴离子表面活性剂 (AOT: 磺基琥珀酸二辛酯钠）和聚合物（PVP-K30：聚乙烯吡咯烷酮）（有时称为 SMART LowSal）用作填砂反应器中的注入流体。由于二次采收后的 NFs（混合）注入，观察到油饱和砂包反应器的石油采收率提高。相对渗透率曲线的特征研究表明，沙子表面最初是亲水的，在 NFs 存在下转变为强亲水。核磁共振（相对渗透率曲线的特征研究表明，沙子表面最初是亲水的，在 NFs 存在下转变为强亲水。核磁共振（相对渗透率曲线的特征研究表明，沙子表面最初是亲水的，在 NFs 存在下转变为强亲水。核磁共振（¹ H NMR) 研究表明，化学物质的吸附出现在砂层表面，这可能是润湿性改变的原因，从而提高了采收率。类似地，注入前后砂样品的扫描电子显微镜 (SEM) 和能量色散 X 射线分析 (EDXA) 揭示了在注入 NFs 后，碳氢化合物从砂表面解吸。由于注入了 NFs，化学驱后石油采收率增加了 5-10%。吸附等温线研究与表面活性剂在砂表面的单层吸附非常吻合。