Plugging property and displacement characters of a novel high-temperature resistant polymer nanoparticle

The goal of the research was to investigate the profile control and oil displacement characteristics of the polymer nanoparticles after high temperature swelling. The displacement parameters showed considerable influence on the plugging effect of the high-temperature swelled polymer nanoparticles, such as the core permeability, concentration of nanoparticles in the suspension, swelling time and swelling temperature, which makes it flexible to control the plugging effect by controlling displacement experiments conditions. Experimental results show that polymer nanoparticles dispersion system with a concentration of 500 mg/L is suitable for cores plugging with a permeability of 30 × 10−3 - 150 × 10−3 μm2, even after aging at 150 °C for three months. The shunt flow experiments show that when the displacement factors are optimal values, the polymer nanoparticles after high temperature swelling to plug the high-permeability layer selectivity and almost do not clog the low-permeability layer. Oil recovery of homogeneous artificial core displacement experiment and a heterogeneous double-tube cores model are increased by 20% and 10.4% on the basis of water flooding. The polymer nanoparticles can be a great help for petroleum engineers to better apply this deep profile control and flooding technology.