三元复合驱中碱提高采收率作用机理  

Enhanced Oil Recovery Mechanism of Alkali in Alkali-surfactant-polymer Flooding

作　　者：魏云云[1,2,3] 罗莉涛 刘先贵[1,3] 刘学伟[3] 刘卫东[3] 杨正明[3] 

机构地区：[1]中国科学院渗流流体力学研究所,廊坊065007 [2]中国科学院大学,北京100190 [3]中国石油勘探开发研究院廊坊分院,廊坊065007 [4]清华大学环境学院,北京100084

出　　处：《科学技术与工程》2017年第5期47-54,共8页Science Technology and Engineering

基　　金：国家科技重大专项(2011ZX05013-006);中国石油科技攻关项目(2014B-1203)资助

摘　　要：研究三元复合驱中碱提高采收率作用机理,对更好地应用其具有重要技术指导作用。设计了界面张力、吸附、乳化、润湿性等多组单一变量对比实验及微观模型、天然岩心驱油实验,研究了碱提高采收率作用机理。结果表明:碱与原油反应生成的表面活性剂。快速地吸附在油水界面上;碱迫使更多的外加表面活性剂进入油水界面,从而增加了界面层中表面活性剂浓度,达到了协同降低油水界面张力作用。碱电离的阴离子与外加表面活性剂在储层基质表面竞争吸附,增加了基质表面负电荷,使其对外加表面活性剂静电斥力加大,降低了外加表面活性剂吸附量。生成的表面活性剂乳化油相,使碱具备了乳化作用。在流动剪切作用下,生成的表面活性剂不断渗入膜状残余油与基质之间,改变了油/基质间、水/基质间界面张力,破坏了油-水-基质之间的原平衡体系,使润湿性由憎水亲油变成亲水憎油。碱提高采收率幅度可达近5%,具备显著提高采收率效应。Research on enhanced oil recovery mechanism of alkali in alkali-surfactant-polymer flooding has animportant technical guiding role for better application of ASP flooding. In order to study enhanced oil recovery mechanism of alkali, single factor contrast experiment has been designed for interfacial tension, adsorption, emulsi-fication, wettability respectively. In order to confirm the emulsification effect of alkali, microcosmic porous and throats model and natural cores oil-displacing experiments have been carried out. The results show： surfactant gen-erated by the reaction between alkali and crude oil could adsorb on the oil-water interface quickly. Alkali could force more surfactant added to adsorb on the oil-water interface. Surfactant concentration in the interface layer in-creased, oil-water interfacial tension were reduced by the synergy effect. Anionic ionized by alkali would happen competitive adsorption on the surface of reservoir matrix, the negative charge increased on the surface of reservoir matrix made reservoir matrix own more the electrostatic repulsion for surfactant added, adsorption were reduced by the effect. Surfactant generated by the reaction between alkali and crude oil could emulsified crude oil. Surfactant generated by the reaction between alkali and crude oil could percolate the interlayer between membrane residual oil and matrix, oil/matrix interfacial tension and water/matrix interfacial tension were changed which destroy the origi-nal balance between oil-water-matrix system. It change the wettability from hydrophobic oil into hydrophilic ab-horred oil. The recovery rate could reach nearly 5% by alkali. Alkali has significantly effect to enhance oil recovery.

关 键 词：三元复合驱 界面张力 吸附 润湿性 采收率 

分 类 号：TE357.46[石油与天然气工程—油气田开发工程]