南堡陆地高含水油藏弱冻胶深部调驱实验研究

deep profile control and flooding; viscoelasticity; movement-detention law; proper injection time; Jidong oil fields

张艳辉 戴彩丽 纪文娟 王思宇 任树亮 杨 帅 赵 光

ZHANG Yan-Hui DAI Cai-Li JI Wen-Juan WANG Si-Yu REN Shu-Liang YANG Shuai ZHAO Guang

针对冀东油田高浅北地区油层的储层特性、非均质特征以及流体性质，评价了酚醛树脂弱冻胶体系的成冻性能。通过调节聚合物和交联剂的加量，形成了一系列成冻时间可调、强度可控的配方，并考察了不同配方冻胶的黏弹性特征，分析了弱冻胶在多孔介质中的运移-滞留规律，评价了不同条件下弱冻胶体系的驱油效果。结果表明，酚醛树脂弱冻胶体系的黏弹性较好，并受聚合物及交联剂浓度的影响较大；弱冻胶调驱体系能够实现在地层中运移-封堵-再运移-再封堵的有限度的驱油过程，起到深部调驱的作用；当弱冻胶注入量为油藏高渗孔隙体积的0.3倍时，单位堵剂的采收率增值达到最大值80%；当水驱含水率达到35%~80%时，调驱后的最终采收率为32.8%~35.9%，效果最好。

According to the reservoir petrophysics, heterogeneity and fluid property in Gaoqianbei area of Jidong oilfield, the gelation ability of phenolic resin cross-linked polymer solution was evaluated. A series formula that controlled the gelation time and strength was formed by adjusting the amount of polymer and crosslinking agent. The viscoelasticity of gels with different concentration were measured. The movement-detention law in the porous media of the gel was explained and its effect of oil displacement was evaluated. The results showed that the phenolic resin cross-linked polymer had a good viscoelasticity feature, and the gel viscoelasticity was obviously affected by the concentration of polymer and crosslinking agent. The gel system could displace the oil finitely by migrating-plugging-remigrating-replugging in the formation and contribute to the deep profile control and flooding. When the gel with 0.3 times of high permeability pore space volume was injected, the oil recovery increment of per unit plugging agent was the highest (80%). When the water-cut was between 35% and 80%, the final recovery after the profile control was up to 32.8%—35.9%.