无碱二元体系提高采收率研究

针对三元复合驱含碱驱油体系引起地层粘土分散和运移、形成碱垢、导致地层渗透率下降,碱还会大幅度降低聚合物溶液的粘弹性,从而降低波及效率等问题,利用不加碱可形成超低界面张力的聚丙烯酰胺-两性表面活性剂二元复合体系,通过可视化仿真岩心驱油试验和人造岩心驱油实验,研究了该二元复合体系的驱油效果。研究表明：在驱替水驱后残余油中,聚合物-两性表面活性剂二元体系可以同时发挥活性剂的超低界面张力特性和聚合物溶液的粘弹特性,使得该二元复合体系的采收率高于单一的表面活性剂体系和聚合物驱油体系。

A Study Of Alkali Free Polymer-Surfactant Compound System for EOR

ASP compound flooding with alkali arouses dispersion and migration of in-situ clay, forming alkali scale leading to formation permeability loss, viscoelasticity decrease of polymer solution, and thus reducing sweep efficiency. This paper presents the alkali free polymer-amphoteric surfactant compound system for EOR by visible simulation and artificial core oil-displacement experiments. The study shows that the mobility control characteristic of polymer and the ultra interfacial tension characteristic of surfactant can be fully utilized in residual oil displacement after water flooding, indicating the sweep efficiency of such a system is higher than that of single surfactant system or single polymer system.