“封窜+复合泡沫驱”与油藏的配伍性研究

Study on Compatibility of"Sealing Channeling+Composite Foam Drive"and Reservoirs

针对目标油田长期水驱开发过程中面临油井水淹现象严重问题,采用“封窜+复合泡沫驱”组合调驱的方法,对层内非均质岩心的每项指标单独比较,得到了适合一般非均质油藏的注水模式。实验结果显示,优选出的封窜体系的储能模量、损耗模量和黏度均随交联剂含量的增加而增大,成胶强度较高。强化泡沫由于加入了聚合物,泡沫液膜强度增大,在岩心中运移时不易消泡,能有效延长泡沫在岩心深部的运移距离。对于层内非均质岩心而言,采收率增幅主要集中于封窜一次泡沫驱阶段,经过组合段塞调剖后,前置凝胶段塞对物性较好的储层能够产生有效封堵。层内非均质储层的前置封窜体系段塞具有重要意义,故尽量体现对高渗透的充分调剖作用。

According to the problems of serious well flooding in the long-term water flooding development process of the target oilfield,the method of"sealing channel+composite foam flooding"was adoptedto compare the indicators of heterogeneous cores within and between layers,and the injection method suitable for generally heterogeneous oilfields was obtained.Experimental results showed that the energy storage modulus,loss modulus and viscosity of the preferred channeling system increased with the increase of crosslinker content,and the glue forming strength was high.Due to the addition of polymers,the strength of the foam liquid film increased,and it was not easy to defoam when transporting in the core,which could effectively extend the transport distance of the foam in the deep part of the core.For intralayer heterogeneous cores,the increase in recovery was mainly concentrated in the channeling+primary foam flooding stage,after the combination section plug was profiled,the pre-gel segment plug could effectively block the reservoir with good physical properties,and the composite foam flooding stage made the liquid flow to the medium and low permeation layer with poor physical properties and expand the sweep volume.The stratified water injection technology of the interlayer heterogeneous reservoir could effectively control the channeling problem in the rock core,so that each oil layer could play a role.