为提高萨尔图油田三类油层实施弱碱三元复合体系驱油效果,开展室内岩心驱替实验,对比分析了不同注入时机、不同聚合物浓度、不同表面活性剂浓度及不同注入方式的驱油效果.结果表明:对于三类油层,水驱转注三元复合体系的时间越早,采收率越高；三类油层实施弱碱三元复合体系驱油时,主段塞聚合物浓度越高,表面活性剂浓度越高,采出程度越高；注入聚合物前置段塞的体积越大,聚合物后续保护段塞体积越大,采出程度越高；相对分子质量为620×104聚合物的三元复合体系中聚合物浓度大于2 750 mg/L时,在水驱基础上化学驱采出程度大于11％；相对分子质量为700×104(抗盐)和相对分子质量为1 400×104聚合物的三元复合体系在水驱基础上化学驱采出程度均大于20％.%In order to improve the efficiency of the displacement of oil by ASP weak alkali in class 3 reseivoirs of Saertu Oilfield, experiments of the displacement of oil with cores are conducted in lab and it is analyzed that different injection times, different polymer injection concentrations, different surfactant concentrations and different injection modes influence displacement effectiveness. The results show that for class 3 reservoirs, the earlier the conversion of water flooding to ASP, the higher the recovery factor; for the implementation of ASP weak alkali in class 3 reservoirs, the higher the polymer concentration in main slug and the higher the surfactant concentration, the higher the recovery percentage; when polymer concentration of ASP with molecular mass of 620 × 104 is greater than 2 750 mg/L, recovery percentage with chemical flooding increases by 11% compared with water flooding; and when molecular mass is 700 × 104 and 1 400 × 104 , recovery percentage with chemical flooding increases by 20% compared with water flooding.
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