交联聚合物微球-聚合物复合调驱注入参数优化设计

Injection parameters optimization of cross-linked polymer microspheres and polymer composite flooding system

针对渤海S油田聚合物驱后吸水剖面改善不明显、油井含水无明显下降等现象,采用交联聚合物微球-聚合物复合调驱技术进行物理模拟实验,研究复合体系组成、驱替速度、注入量等对驱油效果的影响,并优化了复合体系注入参数。研究表明,在复合体系总浓度为1750 mg/L的前提下,体系中交联聚合物微球的浓度越大,采收率提高幅度越大,交联聚合物微球浓度在400-100 mg/L、缔合型聚合物浓度在1350-1650 mg/L范围内,都能取得较好的增油效果;交联聚合物微球-聚合物复合体系驱较单纯聚合物驱可以提高采收率8%-11%。复合体系驱替速度在3.5 m/d左右、注入量为530 mg/L·PV左右时,交联聚合物微球-聚合物复合调驱体系能较好地改善聚合物驱效果。

Based on the facts that there is no obvious improvement in injection conformance and no significant water cut reduction in production wells after polymer flooding in S oilfield in Bohai Bay, this study used cross-linked polymer microspheres-polymer composite flooding to research the effect of chemical system composition, displacement speed, injection volume on polymer flooding by physical simulation experiments, and to optimize injection parameters of composite system. The results showed that the higher the concentration of cross-linked polymer microspheres at a total concentration of 1750 mg/L, the more the oil recovery enhancement; the 1350-1650 mg/L polymer composite system can achieve better oil recovery when the cross-linked polymer microsphere concentration reaches 400-100 mg/L; compared with single polymer flooding, the cross-linked polymer microspheres polymer composite system flooding can enhance recovery factor by 8%-11%; in addition, it was found that the composite system could better improve polymer flooding at the displacement rate of 3.5 m/d and the injection volume of 530 mg/L？PV.