延长油田致密岩性储层低矿化度分层注水技术研究  

Study on Stratified Water Injection Technology with Low Salinity in Tight Lithologic Reservoir in Yanchang Oilfield

作　　者：袁青 李军[1] 郑亚莉[1] 李楠 YUAN Qing;LI Jun;ZHENG Yali;LI Nan(Dingbian Oil Production Plant of Yanchang Oilfield Co.,Ltd.,Yulin Shaanxi 718600,China)

机构地区：[1]延长油田股份有限公司定边采油厂,陕西榆林718600

出　　处：《当代化工》2024年第7期1570-1574,共5页Contemporary Chemical Industry

基　　金：陕西省教育厅专项计划项目(项目编号:20JK0879)。

摘　　要：研究表明低矿化度水注水(LSW)具有提高采收率的潜力。考察二氧化硅纳米颗粒(NPs)在砂岩上的吸附以及其在LSW驱油过程中对流体/岩石相互作用的影响。在砂岩表面的等温静态吸附实验中,纳米颗粒在石英表面表现出比高岭石更高的吸附亲和力。随着盐度的增加,纳米颗粒的吸附能力增强。动态吸附实验中,注入约0.033 g纳米颗粒与示踪剂(约0.13 g氯化锂),估计NPs在岩心驱替过程中的不可逆吸附约为35%,而岩心驱替的解吸率约为21.2%。质量平衡分析实验结果显示,pH对纳米二氧化硅的吸附/脱附过程有一定影响,碱度的增加有利于纳米颗粒的脱附。与单独使用LSW和NP驱相比,在LSW和NP复合驱过程中,纳米颗粒在矿物表面的吸附减少了矿物的溶解。表面力估算表明,LSW与NPs的结合降低了矿物颗粒之间的斥力。将LSW和纳米颗粒相结合形成协同效应,从而降低了砂岩储层的地层损害概率。Studies have shown that the injection of low salinity water(LSW) has the potential to enhance oil recovery.In this paper,the adsorption of silica nanoparticles(NPs) on sandstone and their effect on the fluid/rock interaction during LSW flooding were investigated.In isothermal static adsorption experiments on sandstone surfaces,nanoparticles exhibited higher adsorption affinity than kaolinite on quartz surfaces.As salinity increased,the adsorption capacity of nanoparticles increased.In the dynamic adsorption experiment,about 0.033 g of nanoparticles and tracer(about 0.13 g of lithium chloride) were injected,and the irreversible adsorption rate of NPs in the core displacement process was estimated to be about 35%,while the desorption rate of flooded cores was about 21.2%.The results of mass balance analysis showed that pH value had a certain effect on the adsorption/desorption process of nano-silica,and the increase of alkalinity was conducive to the desorption of nanoparticles.Compared with LSW and NP flooding alone,the adsorption of nanoparticles on the mineral surface during the LSW and NP composite flooding process reduced the dissolution of minerals.The surface force estimation showed that the combination of LSW and NPs reduced the repulsion between the mineral particles.The synergistic effect of combining the two technologies of LSW and nanoparticles reduced the probability of formation damage in sandstone reservoirs.

关 键 词：驱油 低矿化度注水 纳米粒子 提高采收率 

分 类 号：TQ127.2[化学工程—无机化工] TE357[石油与天然气工程—油气田开发工程]