The liquid-blocking effect occurs as the reservoir pressure drops below the dew point, which could increase liquid saturation, decrease flow efficiency and relative permeability, further leading to a sharp decline in production. Gas-wetting alteration has been an effective measure to enhance oil and gas recovery by improving flow efficiency in the blocking area. In this paper, we reported a super gas-wetting nanoparticle, which can alter the rock wettability from liquid-wetting to super gas-wetting at a low concentration within a short time, results show that the contact angles of brine and hexadecane increase from 23° and 0° to 152° and 140°, respectively. FT-IR, SEM, and EDS were employed to determine the morphology change of nanoparticle after gas-wetting alteration, results show that grape-like particles play a vital role in achieving super gas-wetting. Both visualization flooding and simulation are conducted to investigate the flow behavior in gas-wetting porous media. The results of visualization flooding demonstrate that flow efficiency in blocking area can be significantly improved after gas-wetting alteration, leading to a remarkable decrease in liquid saturation. Meanwhile, a phenomenon of the convex liquid bridge was observed, which is of importance to improve the flow efficiency of liquid trapped in pore throat. The dynamic kinetic of the liquid bridge was also investigated by CFD simulation, the result is consistent with that of visualization flooding.
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