基于非均质指数的窄河道油藏调剖选井方法

窄河道油藏注水开发中易水窜、储量动用不均,优选井组调剖十分重要。引入非均质指数,利用产油、产水量累计偏差双重因素,绘制产油产水非均质指数变化图,据图将油井分为4类,其中高油高水井、低油高水井、低油低水井筛选为疑似调剖井;选取目前日产液量和含水率进行二次筛选,认为高日产液量、高含水率油井为待调剖井。为优选调剖剂,应用两步水窜诊断法,即基于含水率及含水变化速度曲线分析油井含水变化规律,通过水油比及水油比导数曲线划分不同油井产水类型。利用本文方法对E油藏调剖井进行了优选,选取注水多通道见水类型的典型井组,进行了聚合物微球调剖现场试验,结果表明,井组含水率缓慢下降,产量稳中有升,说明了本文方法的有效性。

Method on well selection based on heterogeneous indexing for profile control in narrow channel reservoirs

Water channeling and uneven development of reserves are common in narrow channel reservoirs.Therefore well group selection is critical for profile control.The heterogeneous indexing was introduced,and the two factors,i.e.accumulated deviation of oil and that of water production,were used to draw the heterogeneity index change graph.The oil wells were classified into four categories according to the graph,among which the high oil&high water wells,low oil&high water wells,and low oil&low water wells were selected as suspected profile control wells.The current daily fluid production and water cut were selected for the secondary screening,and oil wells with high daily fluid production and high water cut were selected to implement profile control.In order to select the optimal profile control agent,the two-step water channeling diagnostics was used,that is,the water cut change law was analyzed based on water cut and water cut change rate curve,the water production types of different oil wells were classified according to the water-oil ratio and the water-oil ratio derivative curve.The method described in this paper was used for optimal selection of profile control wells in E reservoir.Typical well groups of injection multi-channel water breakthrough type were chosen for the field test of polymer microspheres profile control.The results show that the water cut decreases slowly and the output rises steadily,which indicate that the method in this paper is effective.