聚合物微球粒径与岩芯孔喉的匹配关系研究

根据岩芯孔喉基本计算公式，计算岩芯的平均孔喉直径，通过吸水膨胀后不同大小聚合物微球在岩芯中的封堵效果，研究了聚合物微球大小与岩芯孔喉的匹配关系，确定了聚合物微球在岩芯中具有稳定封堵性能时微球粒径与岩芯孔喉直径的比值范围。从聚合物微球吸水膨胀性能、剪切前后微球粒径变化、不同大小聚合物微球在岩芯中的封堵效果、与岩芯匹配后的聚合物微球调剖作用对水驱采收率的影响几个方面，研究了聚合物微球大小与岩芯孔喉的匹配关系，从而为聚合物微球调剖体系大小选择提供实验依据。研究表明，当聚合物微球粒径与岩芯孔喉直径比值在0.33～1.50 时，聚合物微球可以在岩芯中形成稳定的封堵能力，当聚合物微球粒径与孔喉直径比值在1.20～1.50 时，聚合物微球兼具良好的运移能力和封堵效果。

A Study on Matching Relationship of Polymer Microsphere Size

According to the calculation formula of pore throat size of cores，average pore throat diameter of cores was calculated.The matching relationship between the pore throat and the polymer microsphere size was researched，through analysisof plugging effect of polymer microspheres of different sizes injected in cores. The range of ratio of polymer microsphere sizeto pore throat diameter of cores was determined when stable plugging performance was obtained. Experiments were conductedto investigate swelling properties of polymer microspheres，microsphere size change before and after shearing，plugging effectof different size microspheres，and effect on recovery of profile control of selected polymer microspheres. The experimentalresults elucidated the matching relationship between the pore throat and the polymer microsphere size，and provided experimentalevidence for size selection of polymer microsphere under different reservoir conditions. Results show that rational ratioof polymer microsphere size to pore throat diameter is in the range 0.33～1.50，and then the polymer microsphere has stable plugeffect. When the ratio is in the range of 1.20～1.50，the polymer microsphere has both good plugging effect and good migrationability.