Mostakhdeminhosseini Farshad, Rafiei Yousef, Sharifi Mohammad
Department of Petroleum Engineering, Amirkabir University of Technology, Tehran, Iran.
Sci Rep. 2025 May 14;15(1):16763. doi: 10.1038/s41598-025-01785-7.
Low-salinity waterflooding (LSWF) is an effective enhanced oil recovery (EOR) method, where injecting low-salinity brine disturbs the reservoir's chemical balance to mobilize residual oil. However, clay minerals, abundant in sandstone reservoirs, pose challenges due to their tendency to swell and migrate, leading to permeability reduction and potential formation damage. While the impact of LSWF on clay-related damage is well studied, the role of temperature in exacerbating these effects remains insufficiently explored. This study investigates the effect of temperature on clay swelling and migration using a microfluidic oven and micromodels coated with bentonite and kaolinite. A series of injection tests were conducted under ambient and elevated temperatures, considering the influence of different cation types in the porous media. Image processing techniques were used to assess porosity, effective porosity, and permeability variations. The results indicate that temperature does not significantly affect clay swelling. However, higher temperatures greatly enhance clay migration for both bentonite and kaolinite, leading to severe pore throat clogging, an effect not observed at ambient temperature. These findings highlight the critical role of temperature in LSWF and its potential to exacerbate formation damage, emphasizing the need for careful reservoir management in high-temperature conditions.
低盐水驱油（LSWF）是一种有效的提高采收率（EOR）方法，注入低盐水会扰乱油藏的化学平衡，从而驱替残余油。然而，砂岩油藏中大量存在的粘土矿物，因其具有膨胀和运移的倾向，会带来挑战，导致渗透率降低和潜在的地层损害。虽然低盐水驱油对粘土相关损害的影响已得到充分研究，但温度在加剧这些影响方面的作用仍未得到充分探索。本研究使用微流控烘箱和涂有膨润土和高岭土的微观模型，研究了温度对粘土膨胀和运移的影响。考虑到多孔介质中不同阳离子类型的影响，在环境温度和高温下进行了一系列注入试验。使用图像处理技术评估孔隙度、有效孔隙度和渗透率的变化。结果表明，温度对粘土膨胀没有显著影响。然而，较高的温度极大地增强了膨润土和高岭土的粘土运移，导致严重的孔喉堵塞，这在环境温度下未观察到。这些发现突出了温度在低盐水驱油中的关键作用及其加剧地层损害的可能性，强调了在高温条件下进行仔细油藏管理的必要性。
