为充分发挥二元低张力体系提高驱油效率和二元泡沫体系扩大波及体积的作用,开展了聚合物驱后二元低张力体系与二元泡沫体系交替注入方式提高采收率室内实验研究.采用气流法筛选出的CYL表面活性剂发泡能力强,与无碱表面活性剂具有良好的配伍性.通过界面张力评价实验测得HLX表面活性剂具有较低的界面张力,而且CYL表面活性剂对HLX表面活性剂降低界面张力的能力影响较小.选择CYL为二元泡沫体系的起泡剂、HLX为二元低张力体系的表面活性剂进行聚合物驱后提高采收率实验.通过实验得出,聚合物驱后纯二元泡沫体系的采收率平均值为7.84％,纯二元低张力体系的采收率平均值为5.87％；而边调剖边驱油(0.05 PV的二元泡沫体系+0.05 PV氮气+0.1 PV的二元低张力体系)交替3次的注入方式的采收率平均值为14.22％,该体系在天然岩心中的采收率平均值为12.26％.聚合物驱后,采用边调剖边驱油的注入方式,可以取得良好的效果.%In order to make full plays of improving oil displacement efficiency of the binary low-tension system and enlarging the swept volume of foam system of binary foaming system, the lab. Researches on EOR of the alternative injections of the above systems are carried out after the polymer flooding. Surfactant CYL screened by gas flow method possesses much stronger foaming property and has pretty good compatibility with alkali-free surfactant. Through the test of interfacial tension experiment, HLX surfactant is shown that it has a pretty lower interfacial ten sion ; and furthermore the influence of the former surfactant is limited on reducing interfacial tension of the later. So the former is chosen to be foaming agent of the binary foaming system; the later is acted as the surfactant of the binary low-tension system, and then they are used to conduct EOR experiment after the polymer flooding. It is shown through the experiment that the average EOR values of pure binary foaming and low-tension systems are seperately 7. 84% and 5. 87% after polymer flooding; the same figure of three times of alternative injection between profile control and oil flooding (0.05 PV binary foaming system + 0. 05PV N2 +0. 1PV binary low-tension system) is 14. 22% and furthermore the average recovery factor of the system in natural cores reaches 12. 26% . After polymer flooding, the above alternative injection can obtain much better effects.
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