聚合物与碱和活性剂交替注入驱油效果研究

Flooding efficiency research on alternative injection of polymer and alkaline-surfactant mixture

化学剂段塞优化组合是提高化学驱油效果的有效途径。针对这一实际需求,开展了“聚合物与碱活性剂二元复合体系”交替注入驱油效果物理模拟研究。结果表明,当采用聚合物与二元复合体系交替注入进行驱油实验时,相对于水驱采收率增幅高达30%。研究结果还表明,适当提高二元复合体系注液速度(不超过前一聚合物段塞注入压力值为宜)有利于扩大波及系数,提高采收率,但也不宜过分追求注液速度,以免二元复合体系突破高渗层内的前置聚合物段塞,降低对中、低渗透层的驱油效果。

Optimizing chemical slugs is one of effective methods for enhancing oil recovery during chemical flooding. Aiming at this practical requirement, we do some researches into physical simulation research of flooding efficiency on alternative injection of polymer and alkaline-surfactant mixture. The experiment results show that the increasing amplitude of enhanced oil recovery of model chemical flooding will reach by 30 % when we adopt alternative injection of polymer and alkaline-surfactant mixture to do oil displacement experiment. The experiment results also show that appropriately improving the injection speed of alkaline- surfactant mixture （It is suitable to no more than the injection pressure value of previous polymer slugs） can help enlarge conformence efficiency, and then enhance oil recovery. But we can＇t inject too quickly, otherwise alkaline-surfactant mixture will break through previous polymer slug along with high permeable bed and reduce oil displacement effect of middle and low permeable bed.