渤海稠油早期非均相驱替模式研究及矿场应用

Study and Mine Application on Early Heterogeneous Displacement Mode of Bohai Heavy Oil

针对地下原油黏度大于350 mPa·s的稠油常规水驱技术采收率低、化学驱开发此类油藏尚未建立成熟模式的问题,利用渤海N油田多年非均相驱矿场实践和油藏数值模拟方法,开展先连续注入后交替注入的效果评价及影响因素研究。结果表明,连续注入后吸入剖面反转时机为0.06 PV,交替注入为0.03 PV后缓解;与连续注入相比,交替注入米视吸水指数提高24%;连续注入阶段阻力系数为2.06,交替注入为1.74,降低16%;非均相驱有效注入PV数为0.37~0.48 PV,技术采收率提高5.2%~12.0%,交替注入累增油为连续注入阶段的1.89倍。在此基础上对非均相驱影响因素进行分析,并建立相应技术界限,为该技术在相似油田推广应用提供借鉴。

In view of the problems of low recovery rate of conventional water flooding technology for heavy oil with underground oil viscosity greater than 350 mPa·s and the mature mode of chemical flooding development has not been established,based on the practice of heterogeneous flooding field and reservoir numerical simulation method in Bohai N oilfield for many years,the effect evaluation and the influencing factors of continuous injection after alternating injection are carried out.The results show that the timing ofinhalation profile reversal was 0.06 PV after continuous injection and reliefis achieved after alternate injection at 0.03 PV;compared with continuous injection,the alternating injection increases the apparent water absorption index by 24%;the resistance coefficient during the continuous injection stage is 2.06,while the alternating injection stage is 1.74,reducing by 16%;the effective injection PV number of heterogeneous flooding is 0.37~0.48 PV,the technical recovery rate is increased by 5.2%~12.0%,and the cumulative increase oil of alternately injection is 1.89 times that continuous injection stage.On this basis,the influencing factors of heterogeneous flooding are analyzed,and the corresponding technical boundaries are established to provide reference for the popularization and application of this technology in similar oil fields.