ZN区块三类井组变流度聚合物驱注入参数优化研究

Study on Optimization of Injection Parameters of Variable Fluidity Polymer Flooding in Third Type of Well Groups in ZN Block

由于油层非均质性强,井间、层间、层内差异大,均一化设计注入方案满足不了所有井的需要,更满足不了所有层的需要,因此需从单井入手。在ZN区块PⅠ5~PⅡ10层段选取三类油层中渗透率级别为0.5~0.7μm^(2)的三类井组为研究对象,研究该井组驱替段塞前段注入参数界限。通过改变聚合物黏度、注入速度和段塞大小设计了不同注入方案。使用数值模拟方法对比各个注入方案,综合考虑开发效果、经济效益以及注入压力情况等因素,确定聚合物最优注入黏度、段塞大小和注入速度分别为33 m Pa·s、0.25 PV和0.16 PV·a^(-1);与常规水驱相比,采收率提高了14.24%,优化结果更好地指导了现场变流度聚合物驱的实施。

Due to the strong heterogeneity of the reservoir,significant differences exist between wells,layers,and within layers.The uniform design of injection scheme cannot meet the needs of all wells,let alone all layers.Therefore,a single-well approach is deemed necessary.In this paper,aiming at the third type of reservoirs in the PⅠ5~PⅡ10 layers of the ZN block,the third type of well groups with permeability levels ranging from 0.5μm 2 to 0.7μm~2 were used as research objects,the injection parameter limits in the front section of displacement plug for this well group were investigated.Different injection schemes were designed by varying polymer viscosity,injection rate,and plugging size.Numerical simulation methods were employed to compare the various injection schemes,taking into account factors such as development effectiveness,economic benefits,and injection pressure.The optimal injection viscosity,plugging size,and injection rate for polymer flooding were determined to be 33 m Pa·s,0.25 PV,and 0.16 PV·a^(-1) respectively.In comparison to conventional water flooding,the recovery factor increased by 14.24%.These optimized results provide improved guidance for the implementation of field-variable fluidity polymer flooding.