The Influence of the Combination of Polymer and Polymer-Surfactant Flooding on Recovery

Polymer-surfactant flooding is able to enhance oil recovery greatly because it can improve sweep efficiency and displacement efficiency. However, the surfactant is so expensive that it is impractical for widespread use. After experiments were carried out to evaluate the polymer and the surfactant used, in this article we suggest that combined polymer flooding slug and polymer-surfactant flooding slug should be good for high recovery and low cost. Many physical simulation experiments were conducted to determine the optimal proportion of slug combination. Mechanisms of slug combination are discussed in this article.