Wettability modification of a nano-silica/fluoro surfactant composite system for reducing the damage of water blocking in tight sandstone reservoirs.

In the process of drilling and development of tight sandstone reservoirs, a large number of external fluids can invade the pore structure of the reservoir due to its strong hydrophilicity, resulting in blockage of the pore structure and a decrease in oil and gas production capacity. To reduce the aqueous phase trapping damage of tight sandstone reservoirs, the SiO@KH550/FC-A nano-composite system was prepared to construct hydrophobic surfaces in core samples. First, the surface of nano-SiO was modified by KH550 to prepare nanoparticles with good dispersion.