复合驱过程中化学剂损失与超低界面张力有效作用距离

Chemical agent loss and effective distance of ultra low IFT in ASP flooding

以大庆天然油砂制作填砂管模型,通过改变复合体系的注入量,研究了碱、活性剂、聚合物3种组分的动态吸附特性,并模拟计算了不同注入量下各组分在地层中运移距离与损失量的关系.结果表明,活性剂的损失量最大,在运移1/5井距后即损失约80%;而聚合物和碱的损失分别只有12%和15%.结合界面张力随运移距离的变化情况可以判断,超低界面张力在油层中的有效作用距离有限,而体系在非超低界面张力状态下对采收率的贡献应予以足够的重视.

Dynamic absorption properties of alkali/surfactant/polymer （ASP） have been studied by core flooding tests on Daqing oil sand filling models. The relationship of migration distance of chemical agent in formation and loss has been calculated by changing injection volumes. The results show that the loss of surfactant is maximum which is about 80% injection after 1/5 well spacing migration, and loss of polymer and alkali are only 12% and 15% respectively. Combining with the effect of surfactant concentration on IFT （interfacial tension）, the effective distance of ultra low IFT is very short in oil formation. The contribution of ASP with non-ultra low IFT to oil recovery efficiency should be paid enough attention to.