纳米驱油剂在增注驱油中的作用*

Effect of Nano-sized Oil-displacement Agent in Increasing Water Injection for Oil Displacement

任晓娟 王睿 潘谦宏 齐银 阿斯亚·巴克 罗向荣

REN Xiaojuan WANG Rui PAN Qianhong QI Yin ASYA Barker LUO Xiangrong

为分析纳米驱油剂在低渗储层增注驱油中的作用，评价了以硅烷偶联剂改性的纳米SiO2为主要成分的纳 米驱油剂的基本性能，通过枣湾区块长6 储层天然岩心和微观模型驱替实验研究了纳米驱油剂的流动特征和驱 油特征。结果表明，纳米驱油剂中的纳米颗粒粒径较小，具有较低的油水界面张力、良好的亲水性及一定的静态 吸附能力。30℃下，0.1%纳米驱油剂的油水界面张力为0.784 mN/m，在亲水和亲油载玻片上的润湿接触角分别 为22.5°和16.2°，在长6 岩心表面的平均静态吸附量为0.0033 mL/g。纳米驱油剂可以驱替常规水驱波及不到的 圈闭在小孔隙中的残余油，且能剥离吸附在孔隙表面的油，对片状集中分布残余油的驱替效果好于网状分散分布 的残余油。在微观模型和天然岩心中注入1 PV 0.1%纳米驱油剂后，水驱渗透率分别提高55.2%～56.7%和 34.3%～55.4%，驱油效率分别提高10.9%～21.6%和6.1%～10.1%，增注驱油效果较好。图13表4参19

In order to analyze the effect of nano-sized oil-displacement agent in increasing water injection in low permeability reservoir，the basic properties of nano-sized oil-displacement agent with nano-SiO2 modified by silane coupling agent as the main component were evaluated，and the flow characteristics and displacement characteristics of nano-sized oil-displacement agent were studied through natural core and microscopic model displacement experiments of Chang6 reservoir in Zaowan block.The results showed that the nano particles in nano-sized oil-displacement agent had small particle size，low oil-water interfacial tension，good hydrophilicity and certain static adsorption. At 30℃，the oil-water interfacial tension of 0.1% nano-sized oil-displacement agent was 0.784 mN/m，the wetting contact angle on hydrophilic and oil-wet slide was 22.5° and 16.2° ，and the average static adsorption capacity on the surface of long 6 core was 0.0033 mL/g. The nano-sized oil-displacement agent could displace the residual oil trapped in small pores which could not be swept by conventional water flooding，and could peel off the oil adsorbed on the pore surface. The displacement effect on flake concentrated distribution of residual oil was better than that of network dispersed distribution of residual oil. After 1 PV 0.1% nano-sized oil-displacement agent was injected into the core micro model and natural core，the water flooding permeability increased by 55.2% —56.7% and 34.3% —55.4% ，and the oil displacement efficiency increased by 10.9% —21.6% and 6.1% —10.1% ，respectively，showing good effect of increasing water injection for oil displacement.

10.19346/j.cnki.1000-4092.2021.01.027