Oil Recovery Enhancement by Nanobubbles: Insights from High-Pressure Micromodel Studies

In OW scenarios, NBs demonstrated superior sweep efficiency compared to distilled water, achieving more uniform front propagation and reducing bypassed oil volumes. The improvement can be attributed to the interfacial activity of NBs along with their specific interactions with solid surfaces. In particular, NBs lowered the interfacial tension (IFT) between the oil and aqueous phases, leading to weaker capillary forces that aid in effective oil mobilization. At the pore walls, NBs induced a slippage effect that reduced the pressure drop across OW media, further facilitating displacement. Aside from these fundamental insights, our results demonstrate the utility of N₂ NBs for oil recovery and related applications at elevated pressures, which are often encountered in practical settings.