摘要
已有研究表明二氧化硅纳米颗粒注入储层,可以改变岩石和流体性质(如润湿性、界面张力和粘度),保护储层同时提高采收率.选择百21井区克下组油藏为研究对象,在储层温度压力下交替注入纳米颗粒、表面活性剂和低矿化度水,分析驱替过程中润湿性变化、提高采收率效果和微观剩余油.实验结果表明,在低矿化度水或者表面活性剂驱后注入二氧化硅纳米颗粒,二氧化硅纳米颗粒会沉积在岩心表面,使部分大孔隙被堵塞,二氧化硅纳米颗粒具有一定深部调剖的效果.二氧化硅纳米颗粒会增加低矿化度水和表面活性剂溶液粘度,从而提高流度比.交替注入二氧化硅纳米颗粒、低矿化度水和表明活性剂,使得润湿性呈现周期性改变,同时证明了不同注入方式对微观剩余油改变不同.分别注入纳米颗粒、表面活性剂、低矿化度水来提高采收率效果要优于将表面活性剂和低矿化度水与纳米二氧化硅复配后注入的效果.
The research shows that silica nanoparticles injected into the reservoir can change the properties of rock and fluid(such as wettability,interfacial tension and viscosity),protect the reservoir and improve oil recovery.In this study,Kexia formation reservoir in bai21 well block is selected as the research object.Nanoparticles,surfactants and low salinity water are alternately injected under reservoir temperature and pressure to analyze the wettability change,EOR effect and micro residual oil during displacement.The experimental results show that when nano silica particles are injected after flooding with low salinity water or surfactant,silica nanoparticles will deposit on the core surface and block some large pores.Silica nanoparticles have a certain effect of deep profile control.Silica nanoparticles will increase the viscosity of low salinity water and surfactant solution,so as to improve the fluidity ratio.By injecting silica nanoparticles,low salinity water and surfactant alternately,the wettability changes periodically.At the same time,it is proved that different injection methods have different changes on micro residual oil.The EOR effect of injecting nanoparticles,surfactant and low salinity water is better than that of injecting surfactant and low salinity water combined with nano silica.
作者
辛骅志
杨万里
刘志强
孔祥帅
杨焕强
XIN Hua-zhi;YANG Wan-li;LIU Zhi-qiang;KONG Xiang-shuai;YANG Huan-qiang(Xinjiang Conglomerate Reservoir Laboratory,PetroChina Xinjiang Oilfield Company,Karamay 834000,China;School of Petroleum Engineering,Yangtze University,Wuhan 430100,China)
出处
《陕西科技大学学报》
北大核心
2022年第5期108-116,151,共10页
Journal of Shaanxi University of Science & Technology
基金
国家自然科学基金项目(51704037)。
