多元复合驱采收率影响因素及作用机理研究——以大庆杏树岗油藏为例

Study on the Influencing Factors and Mechanism of Multiple Composite Flooding Recovery——Taking Daqing Xingshugang Reservoir as an Example

近年来,大庆油田复合驱油技术应用和研究取得重要进展,但进一步研究新型复合驱油体系来提高采收率仍然刻不容缓。针对矿场实际需求,以大庆杏树岗油田储层和流体为模拟对象,进行了多元复合驱采收率影响因素及作用机理研究。结果表明:石油磺酸盐+氯化钠+氢氧化钠+聚合物组成的新型复合体系可以扩大波及体积和提高洗油效率。在物理模拟实验过程中,采用“恒速”注入方式时聚合物滞留作用引起注入压力持续升高和扩大波及体积效果相应增长,但矿场化学驱注入压力受到储层破裂压力限制,最终造成实验采收率增幅会远高于实际值,因此选用“恒速-恒压”注入方式实验结果。

In recent years, important progress has been made in the application and research of composite flooding technology in Daqing oilfield. However, it is still urgent to further study the new combined flooding system to improve oil recovery technology. In response to the actual needs of the mine, taking the reservoir and fluid of Daqing Xingshugang Oilfield as the simulation object, research on the factors affecting the recovery factor and the mechanism of multi-element combination flooding were carried out. The results showed that the new composite system composed of petroleum sulfonate + sodium chloride + sodium hydroxide + polymer could expand the sweep volume and improve the oil washing efficiency. During the physical simulation experiment, when the "constant rate" injection method was adopted, the polymer retention could cause the injection pressure increase and increase the effect of expanding the swept volume. Therefore, the "constant speed-constant pressure" injection method experimental results should be chosen.