表面活性剂对鄂尔多斯盆地致密砂岩储层渗吸采收率影响分析  

Effect of Surfactants on Imbibition Recovery of Tight Sandstone Reservoirs in Ordos Basin

作　　者：史伟奇 程宇雄 吴彬 严亮 葛一卓 陈明贵[1] SHIWeiqi;CHEN Yuxiong;WU Bin;YAN Liang;GE Yizhuo;CHEN Minggui(School of Petroleum Engineering,Yangtze University,Hubei,Wuhan 430100,P R of China;CNOOC Research Institute Company Ltd.,Beijing 100029,P R of China;Supervision center of Engineering Technology Branch Company,CNOOC Energy Development Company Ltd.,Tianjin 300451,P R of China;Laboratory testing and Research Institute,Xinjiang Oilfield Branch Company,PetroChina,Karamay,Xinjiang 834000,P R of China)

机构地区：[1]长江大学石油工程学院,湖北武汉430100 [2]中海油研究总院有限责任公司,北京100029 [3]中海油能源发展股份有限公司工程技术分公司监督中心,天津300451 [4]中国石油新疆油田分公司实验检测研究院,新疆克拉玛依834000

出　　处：《油田化学》2023年第1期110-116,共7页Oilfield Chemistry

基　　金：国家自然科学基金“耐温抗盐活性纳米流体润湿性能调控方法与驱油机理研究”(项目编号52104019);海洋石油开发国家重点实验室基金“基于时温等效原理的驱油用聚合物流变性研究”(项目编号CCL2021RCPS0514KQN);中国海油北京研究中心“文昌9-7油田储层改造措施研究”(项目编号CCL2022RCPS0138PSN)。

摘　　要：为了研究致密砂岩储层表面活性剂的渗吸作用机理,首先研究了4种不同类型的表面活性剂润湿性反转能力与降低界面张力能力,并开展了表面活性剂渗吸实验;结合核磁共振测试与高压压汞实验表征了岩心微观孔隙特征,并在渗吸过程中进行核磁共振测试,研究了不同岩心孔隙类型的渗吸作用机理。研究表明:阴离子表面活性剂润湿性反转与降低界面张力的能力更强,且润湿性改变是提高渗吸采收率的关键。致密砂岩孔隙类型为纳米孔(r<0.1μm)、微孔(0.1μm<r<10μm)、宏孔(r>10μm),其中微孔为原油主要储存空间,孔隙体积占比达67.7%;宏孔的渗吸采收率最大,其次为微孔、纳米孔。阳离子活性剂CTAB、两性离子表面活性剂BS-12对渗吸具有抑制作用,非离子表面活性剂APG-12的渗吸效果同样较差;阴离子表面活性剂SDS、AES润湿性改变效果最好。对于致密岩石亲水润湿的质量分数为0.1%表面活性剂溶液,润湿时间(AES<SDS<APG-12)越短,致密岩石微纳米孔喉表面吸附的表面活性剂的数量越多,润湿性转变越强,表面活性剂渗吸采收率(APG-12<SDS<AES)越高。In order to study the mechanism of percolation effect of surfactants in dense sandstone reservoirs,four different types of surfactants were tested for wettability and interfacial tension,and surfactant percolation experiments were carried out.The microscopic pore characteristics of cores were characterized by combining nuclear magnetic resonance(NMR)tests and high-pressure mercury compression experiments,and NMR tests were conducted during percolation to study the mechanism of percolation effect of different pore types.The results showed that the anionic surfactant had a stronger ability to change the wettability and reduce the interfacial tension,and the change of wettability was the key to improve the recovery rate of percolation.The pore types of dense sandstone were classified as nanopore(r<0.1μm),micropore(0.1μm<r<10μm),and macropore(r>10μm),among which micropore was the main storage space of crude oil,with 67.7%of the pore volume.The recovery rate of percolation was the largest for macropore,followed by micropore and nanopore.The cationic surfactants CTAB and amphoteric surfactants BS-12 had inhibitory effect on percolation,and non-ionic surfactants APG-12 had the similar poor percolation effect,while anionic surfactants SDS and AES had the best wettability change effect.For surfactants solution,mass fraction being of 0.1%,with hydrophilic wetting of dense rocks,the shorter the wetting time(AES<SDS<APG-12),the greater the number of surfactants adsorbed on the surface of micro-and nano-pore throats of dense rocks,the stronger the wettability change,and the higher the surfactant percolation recovery(APG-12<SDS<AES).

关 键 词：表面活性剂 渗吸机理 孔隙结构 核磁共振 原油采收率 

分 类 号：TE341[石油与天然气工程—油气田开发工程]