This study presents nano-smart water synthesized with grafted SiO nanoparticles dispersed potential determining ion (PDI) controlled seawater to enhance oil recovery in carbonate reservoirs with high temperatures and high salinity. Phase behavior observation, dynamic light scattering (DLS), and transmission electron microscopy (TEM) were performed to evaluate the dispersion stability of the synthesized nano-smart water with different particle concentrations at 25 ℃ and 80 ℃. In addition, a fluid miscibility test (FMT) was conducted using seawater with controlled salinity and PDI type and concentration. The results of dispersion stability showed that stable fluids without aggregation and precipitation, with an average particle size of less than 100 nm, could be synthesized at room and high temperature in seawater at the nanoparticle concentration 0.5 wt% or more. The dispersion stability of the synthesized nano-smart water was successfully achieved without aggregation and precipitation, with an average particle size of less than 100 nm, at room and high temperatures when the nanoparticle concentration is higher than 0.5 wt%. After performing the FMT with a high-salinity level of up to 200,000 ppm, and implementing PDI control using K, Mg, Cl, and SO, the nanoparticles in nano-smart water still had an average particle size ranging from 32.2 to 54.1 nm. This indicates that the colloidal dispersion was stable despite the high-salinity levels and PDI control. Therefore, the SW-based nano-smart water is expected to be used as a stable injection fluid in high-temperatures and high-salinity carbonate reservoirs.

中文翻译：

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高温高盐条件下海水基纳米智能水的合成及分散稳定性


本研究提出了用接枝 SiO 纳米粒子分散电位确定离子 (PDI) 控制的海水合成的纳米智能水，以提高高温和高盐度碳酸盐岩储层的石油采收率。通过相行为观察、动态光散射（DLS）和透射电子显微镜（TEM）评估不同颗粒浓度合成的纳米智能水在25℃和80℃下的分散稳定性。此外，还使用盐度以及 PDI 类型和浓度受控的海水进行了流体混溶性测试 (FMT)。分散稳定性结果表明，纳米粒子浓度在0.5 wt%以上时，在常温和高温海水中可合成不聚集、不沉淀、平均粒径小于100 nm的稳定流体。当纳米颗粒浓度高于0.5 wt%时，合成的纳米智能水在室温和高温下成功实现了分散稳定性，无聚集和沉淀，平均粒径小于100 nm。在进行高达 200,000 ppm 的高盐度 FMT 并使用 K、Mg、Cl 和 SO 进行 PDI 控制后，纳米智能水中的纳米颗粒的平均粒径仍然在 32.2 至 54.1 nm 之间。这表明尽管有高盐度水平和 PDI 控制，胶体分散体仍然稳定。因此，基于SW的纳米智能水有望作为高温高盐碳酸盐岩油藏的稳定注入流体。