Objective In order to decrease the water-blocking damage in low oil and gas reservoirs, a cationic alkyl glycoside bio-based wetting regulator was synthesized using dodecyl glycoside and 3-chloro-2-hydroxypropyltrimethylammonium chloride.
Method The regulator structure was characterized by infrared spectroscopy and proton nuclear magnetic hydrogen spectroscopy, and the cationic alkyl glycoside was investigated for its temperature and salt resistance, wetting regulating properties, adsorption properties on sandstone surfaces, and permeability recovery values in artificial rock cores.
Result The bio-based wetting regulator has good temperature resistance, and the contact angle of the sandstone surface was adjusted to 89.36° in a high temperature and high salt environment of 150 ℃ and 10 wt% NaCl, which could effectively reduce the capillary pressure and decrease the water-blocking damage caused by the foreign water phase, so as to achieve the protection of oil and gas reservoirs. Through permeability experiments, the core permeability recovery value of this bio-based wetting regulator could reach more than 120%, and showed excellent water-blocking performance.
Conclusion This wetting regulator system has anti-temperature, anti-salt and wetting regulating properties, which can effectively decrease the water-blocking damage of oil and gas reservoirs.