聚合物驱后凝胶与化学剂交替注入的驱油效果研究

Comparative Research of Gel and Chemicals Alternating Injection after Polymer Flooding

聚合物驱后油藏仍有大量剩余油残留其中,为探讨进一步提高聚合物驱后油藏的原油采收率的方法,利用人造非均质大平板岩心,开展了凝胶与聚合物、凝胶与聚合物/表面活性剂二元复合体系(简称聚表二元体系)多轮次交替注入的驱油效果研究。结果表明,交替注入0.26 PV凝胶与0.39 PV聚表二元体系进行驱油实验,采出程度可在聚合物驱采收率基础上提高11.29%,凝胶与聚合物溶液交替注入驱油阶段采出程度可提高7.10%,说明凝胶与聚表二元体系交替注入驱油技术对聚合物驱后剩余油的进一步挖潜更具潜力,但与凝胶与聚合物交替注入驱油技术相比,其成本相对较高。在现场进行实际技术优选时应综合考虑成本及市场原油价格等因素。

In order to dip remaining oil further in reservoir after polymer flooding, the comparative experiments were carried out by alternately injecting the slug of the gel and polymer/surfactant compound system or the slug of gel and polymer solution into artificial heterogeneity large fiat core. The experimental results showed that, by alternately injecting 0.26 PV gel and 0.39 PV polymer/surfactant slug after polymer flooding, the oil recovery could be enhanced more than 11.29% on the basis of polymer flooding, while the oil recovery could be enhanced more than 7.10% by alternately injecting 0.26 PV gel and 0.39 PV polymer slug, which indicated that compared with the alternate injection of gel and polymer, alternately injecting the slug of the gel and polymer/surfactant had more potential on further developing the residual oil and enhancing the recovery after polymer flooding, but the cost of the former was higher. Therefore, apart from the recovery, the other factors must be considered, such as cost and market price of crude oil, in actual technique optimization.