有机碱三元复合驱体系与正构烷烃间的界面张力

Interfacial Tensions between Organic Alkaline/Surfactant/Polymer Flooding System and n-Alkanes

郭淑凤

GUO Shufeng

为明确有机碱、表面活性剂、聚合物三者之间的协同效应，采用旋转滴法研究了有机碱三元复合驱体系与正构烷烃间的界面张力。研究结果表明，非离子表面活性剂烷醇酰胺6501能够有效降低正癸烷油水间的界面张力，浓度为2.0 g/L时6501溶液与正癸烷间的界面张力稳态值为10-1 mN/m；有机碱乙醇胺或二乙醇胺的加入可以进一步将体系与正癸烷间的界面张力降至10-2 mN/m，这主要是由于有机碱能够影响烷醇酰胺的溶解性及其在界面上的分子排列，乙醇胺降低界面张力的能力大于二乙醇胺；聚合物类型对有机碱三元复合体系与正癸烷间的界面张力有较大影响，加入水溶性聚合物后的有机碱三元体系与正癸烷间的界面张力可降至10-3 mN/m，而加入疏水缔合聚合物后的有机碱三元体系与正癸烷间界面张力瞬时值升高，稳态值变化不大，保持在10-1 mN/m数量级。图7参15

In order to understand the synergistic effect among components of organic alkaline/surfactant/polymer (OASP) flooding system, the interfacial tension (IFT) between OASP flooding system and n-alkanes were studied using the spinning drop method. The results showed that the nonionic surfactant alkanolamide 6501 could effectively reduce the oil-water IFT. At an optimum concentration of 2.0 g/L, the IFT between n-decance and 6501 surfactant solution could be decreased to 10-1 mN/m. The addition of organic alkalines (monoethanolamine or diethanolamine) would further reduce the IFT to 10-2 mN/m by increasing the solubility and molecular arrangement of 6501 at the oil/water interface. Monoethanolamine has a stronger ability of reducing IFT than diethanolamine. Moreover, the different types of polymers have significant influence on the IFT of OASP system. Water-soluble polymer would reduce the IFT to 10-3 mN/m, while hydrophobic association polymer would increase the dynamic IFT value and the steady IFT remained to be 10-1 mN/m order of magnitude.