聚合物纳米微球调驱性能室内评价及现场试验

针对河南油田油藏物性特征及传统调剖效果差的问题,在确定聚合物纳米微球膨胀倍数的基础上,结合油藏物性计算出了聚合物纳米微球的初始粒径。通过流动试验测试了聚合物纳米微球对单填砂管的封堵率及高低渗透率平行填砂管注聚合物纳米微球后的采收率,结果表明:聚合物纳米微球对单填砂管的封堵率达到80.5%,单填砂管注入聚合物纳米微球后不同区域压力波动幅度不同,表明微球在填砂管中发生了运移、封堵、弹性变形、再运移和封堵过程;聚合物纳米微球优先进入并封堵高渗透率填砂管,改变高低渗透率填砂管的非均质性,启动低渗透率填砂管内原油,高低渗透率填砂管整体采收率提高20.5%。柴9井的试验表明,注水井注入聚合物纳米微球后,注水井的注入压力升高,吸水剖面发生显著变化,与其对应的油井产油量增加。采用聚合物纳米微球深部调驱技术可以实现深部调剖,扩大注水波及体积,提高原油采收率。 

Evaluation and Application on Profile Control of Polymer Nano-Microspheres

According to the physical property of the reservoir in Henan Oilfield and the poor effect of profile control,the initial particle size of polymer nano-microsphere was optimized based on the expansion volume of polymer nano-microsphere and reservoir characteristics.Through flowing test of the core,the plugging rate in single sand pipe and the EOR after injecting polymer nanoparticles were studied in high and low permeability parallel sand pipes.The results showed that plugging rate of the polymer nanoparticles in the sand pipe reached 80.5%,and different areas had different fluctuating pressure after water flooding with the polymer nanoparticles.This indicates that migration,plugging,elastic deformation,re-migration and re-plugging occurred with the polymer nanoparticles in sand pipe.Polymer microspheres entered and blocked the hypertonic pipe first,and then changed the heterogeneity of parallel sand pipe,finally,crude oil in low permeability was driven.During the process,the oil recovery ratio of the high permeability sand pipe improved 20.5%.The field application in Well C9 showed that,after polymer nanoparticle flooding in injection well,the injection pressure increased,water injection profile significantly changed,and the corresponding oil well production increased.The test indicates that deep profile control with polymer nanoparticle is suitable for Henan Oilfield.This technology can realize deep profile control,increase swept volume and enhance oil recovery.