Study on Profile Control and Water Shut‐Off Performance of Interpenetrating Network Polymer Gel Composite System in Shallow Low Temperature Fractured Oil Layer

Abstract

AbstractIn order to solve the problem/address the issue of oil saturation reduction in the near‐wellbore region of low‐temperature fractured reservoir in Fuyu oilfield, it is especially necessary to carry out in‐depth profile control plugging technology research. In this paper, composite system of particle plugging agent and new interpenetrating network gel were optimally designed, and the non‐fractured cores and fractured cores were used for plugging experiment and oil displacement, the in‐depth profile control mechanism of the composite system was obtained. The results show that the gelation time of the new interpenetrating network gel system can reach 6–7 hours under low temperature conditions (30 °C), with strong shear resistance and viscosity retention. The waterflooding efficiency of fractured core is lower than that of non‐fractured core. After injection of different profile control system, improved recovery efficiency of fractured core is larger than that of non‐fractured core, but the ultimate oil recovery of fractured core is still smaller than that of non‐fractured core. The gelation effect and strength of the composite system are better than that of new interpenetrating network gel agent. The addition of the expanded particles in the system greatly enhances the overall strength and anti‐interference ability. This study can provide theoretical guidance for in‐depth profile control of low temperature fractured reservoirs.