萨中地区聚合物驱前后密闭取心井驱油效果及剩余油分析

Analysis on the result and remaining oil of the sealed coring wells drilled before and after polymer flooding

采用数理统计方法,根据萨中地区中区西部、北一区断西聚合物驱前后钻取的4口密闭取心井资料,分析了聚合物驱前后油层水洗状况、油层动用条件及剩余油分布特征。分析认为,聚合物驱调整了层间、层内剖面,提高了动用厚度;可通过提高水洗程度来提高驱油效率,但降低水驱残余油的难度很大。聚合物驱后剩余油很少,且分布十分零散,挖潜难度极大,进一步挖掘聚合物驱后剩余油的方向主要应以提高驱油效率为主。

Using mathematical statistical method and basing on the data of four sealed coring wells (two drilled before polymer flooding and two after polymer flooding) , this paper analyzes the water-out behavior and producing condition of the pay zone and the characteristic of the distribution of remaining oil. The analysis shows that the polymer flooding changes the internal and interlayer profile, and enhances the producing thickness. Polymer flooding can enhance the oil displacement efficiency through enhancing the water-out degree. But it is very difficult to decrease the waterflood remaining oil. The remaining oil is short and scattered. It is difficult to dig it. To dig the remaining oil after polymer flooding should mainly depend on increasing the oil displacement efficiency.