纳米SiO2/SDS分散体系的稳定性及界面活性  

Stability and Surface Activity of Nano-SiO2/SDS Dispersion Systems

作　　者：王伟琳 陈五花 丁名臣[2,3,4] 王业飞[2,3,4] WANG Weilin;CHEN Wuhua;DING Mingchen;WANG Yefei(DongSheng Jinggong Petroleum Development Group Co.Ltd.,Shengli Oil Field,Dongying,Shandong 257051,P R of China;Key Laboratory of Unconventional Oil&Gas Development(China University of Petroleum(East China)),Ministry of Education,Qingdao,Shandong 266580,P R of China;Shandong Key Laboratory of Oilfield Chemistry,School of Petroleum Engineering,China University of Petroleum(East China),Qingdao,Shandong 266580,P R of China;School of Petroleum Engineering,China University of Petroleum(East China),Qingdao,Shandong 266580,P R of China)

机构地区：[1]胜利油田东胜精攻石油开发集团股份有限公司,山东东营257051 [2]非常规油气开发教育部重点实验室(中国石油大学(华东)),山东青岛266580 [3]山东省油田化学重点实验室,山东青岛266580 [4]中国石油大学(华东)石油工程学院,山东青岛266580

出　　处：《油田化学》2020年第3期456-461,共6页Oilfield Chemistry

摘　　要：纳米颗粒/表面活性剂分散体系的稳定性是一个不容忽视的问题,为了使其在油田得到实际应用,应对分散体系的稳定性及界面活性进行研究。通过沉降实验、浊度及Zeta电位测定研究了离子组成、SiO2的含量和pH值与纳米SiO2/十二烷基硫酸钠(SDS)体系稳定性的关系,并研究了上述条件下纳米SiO2对SDS降低油水界面张力的影响。研究结果表明,在NaCl盐水中,体系稳定性较好,纳米SiO2的加入有助于SDS降低界面张力。模拟地层水中,纳米SiO2含量的增加,二价Ca^2+,Mg^2+离子的存在,均使体系稳定性变差。SDS降低界面张力的能力随着SiO2含量的增加先增后减,界面张力在0.5%时达到最低。在酸性介质中,颗粒间水化作用的增强及SiO2颗粒周围H^+保护层的存在使模拟地层水中体系稳定性得到明显改善。在SiO2质量分数大于0.5%时,更低的pH有利于提高体系降低界面张力的能力。The stability as well as the interfacial activity of nanoparticle/surfactant dispersion system should be analyzed for its application in enhanced oil recovery processes.The influence of ion composition,nano-SiO2 content and pH value on the stability of nano-SiO2/SDS systems were analyzed by sedimentation,nephelometry and Zeta potential measurements.The effects of nano-SiO2 on the capability of SDS to reduce interfacial tension were also studied under the same conditions.The experimental results suggested that in NaCl brine,the nano-SiO2/SDS systems had good stability,and the addition of nano-SiO2 could enhance the ability of SDS to reduce interfacial tension.In simulated formation water,the increase of nano-SiO2 content and the presence of divalent Ca^2+and Mg^2+ions tended to destabilize the system,the ability of SDS to reduce interfacial tension first increased and then decreased with the increase of nano-SiO2 content,the interfacial tension reached a minimum at 0.5%nano-SiO2.In acidic medium,the enhanced intergranular hydration force and the presence of H^+protective layer around nano-SiO2 could improve the stability of the system in the formation water.And when the mass fraction of nano-SiO2 was more than 0.5%,the lower pH value was beneficial to improve the ability of the system to reduce the interfacial tension.

关 键 词：纳米SIO2 十二烷基硫酸钠 ZETA电位 PH值 界面张力 

分 类 号：TE[石油与天然气工程]