The Matching Experiment Of Deep Profile Control System And Reservoir Permeability In Gel Microcapsules

The matching of the gel microspheres with the reservoir permeability of seriously affect the injection, plugging performance and profile control effect of the reservoir. In order to meet the reservoir to enhance oil recovery, the gel microspheres matched with reservoir pore throat scale characteristics are the key to deep profile control technology. In this paper, the physical simulation experiments of the injection and plugging performance of nano gel microcapsules are carried out with artificial core, evaluating the injection and plugging performance of nano gel microcapsules in the cores with different permeability and explore the matching relationship between nano gel microcapsules and reservoir permeability; moreover, the profile control effect of nano gel microcapsules is studied by profile control experiment in the artificial heterogeneous core. All the experimental results show that:（1）The injection and plugging experiments of the gel microcapsules in the cores with permeability of 1240.94 mD, 631.41 mD, 288.43 mD, 43.45 mD, 2.05 mD show that, nano gel microcapsules have good injection and plugging performance in the core with permeability of 631.41 mD. Besides, the residual resistance factor is high in the segments of the core. From the comprehensive evaluation of the injection and plugging ability, the matching relationship between nano gel microcapsules and the core with the permeability of 631.41 mD is good, while the matching relationship between nano gel microcapsules and the core with the permeability of less than 10 mD or greater than 1000 mD is poor.（2）The permeability contrast of the artificial heterogeneous core is 10. In order to further improve the profile control effect, it is essential to further study the matching relationship between the gel microcapsules and the reservoir permeability and the heterogeneity, and optimize the particle size of the gel microcapsules.（3）Cr³⁺ polymer gel flooding effect is the best, followed by the " high molecular weight " polymer solution, and nanoparticle oil displacement agent is the worst. Using low concentration " high molecular weight " polymer solution（CP=200mg/L 400mg/L） as the carrying liquid of nanoparticle is recommended. The later injection time, the higher the final recovery of nanoparticle flooding. Nanoparticle oil displacement agent has a low interfacial tension（1.2×10-2mN/m）, which can reduce injection pressure. The greater the concentration of nanoparticles and the larger the amount of nanoparticles, the better the effect of increasing oil. However, with the increase of the amount of nanoparticles, the increase of the recovery of nanoparticle flooding showed a gradual decreasing trend. Compared with "bulk polymer particle profile control + nanoparticle flooding ", "Cr³⁺ polymer gel profile control + nanoparticle flooding " has a better effect of increasing oil.