关键词: 低渗储层, 纳米微球, 黏弹性能, 调驱性能

Abstract: Aiming at the reservoir characteristics of strong reservoir heterogeneity, circulation way widely distributed and poor water flooding effect in X oilfield of yanchang, a kind of nano⁃microsphere oil displacement agent WQ⁃3 was systhesized. The microstructure, swelling property, viscoelasticity and shear resistance performance were evaluated through the indoor experiments. The core⁃flow experiment was used to evaluate the performance of the regulator in heterogeneous core. The results showed that nano⁃microsphere WQ⁃3 are spherical nanoparticles with good roundness and the average particle size is 404.92 nm. At 80 ℃ in simulated formation water, the expansion ratio of the nano⁃microspheres after 24 h of water absorption is 34.96 g/g. Nano⁃microsphere WQ⁃3 has obvious viscoelastic properties after water absorption, showing the properties of soft solids. At high shear rate, nano⁃sphere WQ⁃3 system has better shear resistance; the injection pressure rises rapidly and the oil recovery increased as high as 14.25% of the injection of WQ⁃3 system.

Key words: Type of reservoirs, Nano?microsphere, Viscoelasticity property, Profile control property