碱剂对复合驱油体系性能的优化

Optimization of alkali agent on performance of ASP system

吴文祥1,张栋1,阚亮1,郎丽媛2

Wu Wenxiang1, Zhang Dong1, Kan Liang1, Lang Liyuan2

1.东北石油大学提高油气采收率教育部重点实验室,黑龙江大庆163318;2.成都理工大学能源学院,四川成都610059

1.MOE Key Laboratory of Enhanced Oil Recovery, Northeast Petroleum University, Daqing 163318, China;2.College of Energy Resources, Chengdu University of Technology, Chengdu 610059, China

结合河南油田储层特性，在ZL-Ⅱ型聚合物+SHSA-HN6表面活性剂二元复合驱油体系的基础上，研究了碱剂Na2CO3的加入对复合体系各项性能的优化程度。实验结果表明，加入碱剂一方面可进一步降低复合体系的界面张力，另一方面，由于竞争吸附，碱在一定程度上对表面活性剂起到保护作用，复合体系加入碱后，溶液的乳化性能得到改善。河南油田天然岩心在进行复合驱后，其润湿性由弱亲水转变为强亲水。现场试验证明，采用弱碱三元复合驱油体系驱油可获得较高的注采比。

Combined with the reservoir characteristics of Henan Oilfield and based on the SP flooding of Z-Ⅱ+SHSA-HN6, this paper studies the optimal degree for each property of the composite system with Na2CO3 added. The experimental results show that the interfacial tension of ASP system can further reduce with adding alkali agent. Due to the competitive adsorption, the alkali agents play a protective role for surfactant. The emulsifying property of the composite system is improved after adding alkali solution. The natural core of Henan oilfield is changed from hydrophilic to the strong hydrophilic flooding after ASP flooding. Field test shows that high injection-production ratio can be obtained by using the weak base ASP system.

10.6056/dkyqt201306023