聚驱后残留聚合物分布及对二元驱的增效作用

针对如何将聚驱后残留在油藏中的有限聚合物发挥出最大限度效益的问题，开展了聚驱后残留聚合物分布及 对二元复合驱增效作用的研究。研究中调研并系统总结了目前国内外聚合物驱后的提高采收率方法，进行了符合海 上油田S 区块油藏地质特征的大型三维平面物理模型实验研究，通过对水驱、聚驱、聚驱+ 表面活性剂的二元复合驱 及后续水驱等不同阶段的聚合物溶液的黏度场、浓度场和压力场等值线图的取样监测，认识了残留聚合物的分布规律 及对聚驱后二元复合驱的影响。结果表明：注聚结束时，主流线浓度最高，两翼部分最小；后续水驱结束，主流线浓度 最小，聚合物大部分被驱出。岩芯中残留的聚合物越多，对二元复合驱的辅助作用越强，注聚结束后越早实施接替技 术越好。研究成果对聚驱后如何利用接替技术继续提高产量具有重要的指导意义。

The Distribution of Residual Polymer and the Synergistic Action of Binary Combination Flooding After Polymer Flooding

To maximize the benefit of residual limited polymer in the reservoir，we carried out a study on the distribution of residual polymer and the synergistic action of binary combination flooding after polymer flooding. On the basis of the survey and summary of the improved oil recovery methods after polymer flooding at home and abroad，the 3D plane large physical model experiments were carried out which accorded with the geological characteristics in offshore oil field S block. By sampling and monitoring the contour diagram of polymer solution viscosity field，concentration field and stress field during the different stages of water flooding，polymer flooding，binary combination flooding and subsequent water flooding，the distribution law of residual polymer and the influence of binary combination flooding after polymer flooding were obtained. The results show that， at the end of the polymer flooding，the concentration of mainstream line was the highest，and the concentration of two wings was the smallest. At the end of subsequent water flooding，the concentration of mainstream line was the smallest，and most of the polymer was driven out. The more residual polymer in core，the stronger the auxiliary function of binary combination flooding. After the polymer injection，the earlier implement of replacement technology，the better development effect. The study has important guiding significance for research on how to use the replacement technology after polymer flooding.