Study on Influencing Factors of Throat-like Residual Oil

Abstract

The microscopic visualization model is used to carry out oil displacement experiments, to test the interfacial tension of the ASP system, and to study the effect of different conditions on the throat-like residual oil by recording dynamic images of the residual oil during the displacement process. The results show that: when the concentration of polymer and alkali is unchanged, the higher the concentration of surfactant, the lower the interfacial tension of the ASP system; the water-wet attribute model is more conducive to the oil displacement system's use of residual oil. The lower the interfacial tension of the ASP system, the better the effect on the throat-like residual oil. when the interfacial tension reaches 10-2, the effect is obvious; after water flooding, the pore-throat ratio and the maximum diameter of the pores have little effect on the residual oil distribution. It has an effect on the residual oil distribution of the minimum diameter of the pores. After the ASP flooding, the large pore-to-throat ratio, the small minimum diameter, and the small maximum diameter have a greater impact on pores with different wettability.