聚合物-泡沫调驱影响因素实验研究

Experimental study on influencing factors of profile control and displacement with polymer-foam

聚合物-泡沫复合调驱是一项重要的提高采收率技术。针对锦州9-3油田的聚合物-泡沫体系,进行了不同注入参数(气液比、注入速度)下调堵能力、驱油效率的物理模拟实验,对聚合物-泡沫体系的调驱能力变化规律进行了研究,并且对聚合物在聚合物-泡沫复合调驱过程中的作用进行了探讨。实验结果表明:采用段塞式注入时大量泡沫是瞬间产生的,聚合物-泡沫体系的最佳气液比为1∶1,阻力系数达40.2,平均封堵强度达3.10 MPa/m。在水驱含水率达到100%后,进行聚合物-泡沫复合调驱采收率提高28%,含水率降低了44%。同时,聚合物在泡沫调驱过程中具有双重作用,一方面,聚合物明显提高了泡沫的稳定性;另一方面,在起泡剂中加入聚合物后不利于泡沫在油藏深部的生成和运移。

Compound profile control and displacement with polymer-foam is a promising enhanced oil recovery technology.In present studies,it has been evaluated by physical simulation.Aiming at the polymer-foam system of 9-3 Oilfield in Jinzhou,physical modeling experiment of profile control and water plugging capability and oil displacement effect is conducted in terms of different injection parameters（gas-liquid ratio and injection rate）.Change rules of profile control and displacement capability of polymer-foam system are studied.Moreover,the action of polymer is also discussed in the process of profile control and displacement.The experimental results show that a great number of foam is simultaneously formed when the slug injection is used.The optimized gas-liquid ratio is 1∶1,resistance coefficient is 40.2 and average blocking intensity is 3.10 MPa/m.When water content reaches 100% after water flooding,the recovery ratio increases by 28% and the water content decrease by 44% for compound polymer-foam displacement.They also show that the polymer has the double action during foam profile control and displacement.On the one hand,the polymer obviously improves the stabilization of foam;on the other hand,polymer adding in foaming agent is unfavorable for the generation and migration of foam in deep reservoir.