胜利油田无碱复合二元驱油体系的研制与性能评价

Development and Performance Evaluation of an Alkali-free Composite Flooding System for Shengli Oilfield

潘逸平 葛际江

PAN Yiping，GE Jijiang

为降低无碱二元复合驱的油水界面张力，同时保持聚合物溶液的黏度，针对胜利ST油田的地层条件，研究了表面活性剂油酸酰胺羧基甜菜碱（OAB）、烷醇酰胺（WCXA）对疏水缔合聚合物（AP）溶液的黏度及其与胜利油田原油界面张力的影响，评价了复合表面活性剂与AP组成的二元驱油体系的驱油性能。结果表明，单一的WCXA或OAB与AP组成的二元体系与原油间的界面张力达不到超低值。WCXA与OAB复配可产生协同效应，增加 WCXA 的比例可以提高体系的黏度保留率，而增加 OAB 的比例有利于油水界面张力的降低。当WCXA与OAB复配质量比为3∶1、复合表面活性剂加量为0.1%~0.4%、AP加量为0.15%~0.25%时，油水界面张力值可在2 h内降至10-3mN/m数量级，且体系黏度保留率为102%~111%。配方为0.25% AP、0.4%复合表面活性剂的复合体系可在水驱基础上提高采收率36%，驱油效果良好。

In order to reduce the interfacial tension between oil and water in alkali-free binary flooding and maintain the viscosity of polymer solution at the same time，aiming at the formation conditions of Shengli ST oilfield，the effects of surfactants such as oleic acid amide carboxybetaine（OAB）and alkanolamide（WCXA）on the viscosity of hydrophobic associating polymer（AP）solution and its interfacial tension with crude oil of Shengli ST oilfield were studied. And the oil displacement performance of binary oil displacement system composed of compound surfactant and AP was evaluated. The results showed that the interfacial tension between the binary system composed of single WCXA or OAB and polymer AP and crude oil could not reach ultra-low value. The combination of WCXA and OAB could produce synergistic effect. Increasing the proportion of WCXA could improve the retention rate of viscosity，while increasing the proportion of OAB was beneficial to decrease the interfacial tension between oil and water. When WCXA and OAB were compounded in a mass ratio of 3∶1，the dosage of compound surfactant was 0.1%-0.4%，and the dosage of AP was 0.15%—0.25%，the interfacial tension between oil and water could be reduced to 10-3 mN/m order of magnitude in 2 hrs，and the viscosity retention rate of polymer ranged from 102% to 111%. The composite system of 0.25% AP and 0.4% composite surfactant could improve oil recovery by 36% on the basis of water flooding，showing good oil displacement effect.

10.19346/j.cnki.1000-4092.2019.03.009