Gemini表面活性剂强化有机铵盐的防膨性能研究

Study on anti swelling and injection technology of ammonium salt strengthened by Gemini surfactant

针对低渗透储层粘土矿物水化膨胀、运移以及注水压力高而导致油田采收率大幅度降低的问题,作者以长碳链烷基叔胺和1,3-二溴丙烷为原料合成系列阳离子Gemini表面活性剂(Cn-3-Cn),以乙二胺和甲酸为原料合成了有机铵盐类防膨剂(EMN),并将二者以一定比例复配,通过评价防膨性能、表/界面活性,得出表面活性剂C14-3-C14与防膨剂的复配效果最好。在0.1%C14-3-C14中加入1.5%EMN+0.5%KCl,防膨率为84%,水洗10次之后防膨率稳定在65%左右;在0.1%C14-3-C14+0.5%KCl复配溶液中加入0.8%、1.5%及3%EMN时,界面张力均可降低至10^(-2) mN·m^(-1),可得到既可以防止粘土膨胀也可以同时降低界面张力的多效增注剂。

In view of the problem that the oil recovery of oil field is greatly reduced due to the hydration expansion,migration and high water injection pressure of clay minerals in low permeability reservoir,the author synthesized a series of cationic gemini surfactants from long-chain alkyl tertiary amine and 1,3-dibromopropane,and synthesized organic ammonium salt anti swelling agents from ethylenediamine and formic acid,By evaluating the anti swelling performance and surface/interface activity,it is concluded that the compound effect of C14-3-C14 and anti swelling agent is the best.When 1.5%EMN+0.5%KCl is added to 0.1%C14-3-C14,the anti swelling rate is 84%,and the anti swelling rate is stable at about 65%after 10 times of water washing;When 0.8%,1.5%and 3%EMN are added to the 0.1%C14-3-C14+0.5%KCl compound solution,the interfacial tension can be as low as 10^(-2) mN·m^(-1),and a multi effect injection enhancer can be obtained,which can not only prevent clay expansion,but also reduce the interfacial tension at the same time.