塔河油田碳酸盐岩储层暂堵转向压裂排量优化

塔河油田碳酸盐岩储层暂堵转向压裂成功，但施工过程中排量参数尚未有计算数据支撑，不利于暂堵转向重复酸压技术推广应用。以裂缝几何形状模型为基础，利用数值迭代方法建立了暂堵转向压裂排量优化设计模型，确定了碳酸盐岩暂堵阶段和压裂阶段最优化排量，形成了“低排量注入暂堵液封堵尖端，高排量注入压裂液实现转向”的暂堵转向施工方法。分析发现:排量要同时满足转向压力需求和裂缝长度需求；随着时间延长，排量开启裂缝扩展长度逐渐无法满足暂堵剂所需裂缝长度，暂堵剂起不到转向作用。利用优化设计模型对现场条件进行排量优化表明，暂堵阶段排量控制在3.0 m3/min以下、压裂液压裂阶段施工排量控制在6.0 m3/min以上，最适合转向压裂。研究为现场应用提供了理论支撑。

Optimizing the displacement of temporary plugging and diversion fracturing of the carbonate reservoirs in Tahe Oilfield

The temporary plugging and diversion fracturing of carbonate reservoirs in Tahe Oilfield is successful, but the displacement parameters in the process of construction have no support of calculation data, which is not beneficial to the popularization and application of temporary plugging and diversion multiple fracturing. The optimization design model of the displacement of temporary plugging and diversion fracturing was established by means of the numerical iterative process based on the fracture geometry model. Then, the optimal displacements in the temporary plugging stage and the fracturing stage of carbonate reservoir were determined. Finally, the construction method of temporary plugging and diversion was developed, i.e., injecting temporary plugging agent at low displacement to plug the tip and injecting fracturing fluid at high displacement to realize diversion. It is indicated that the displacement shall meet the need of diversion pressure and fracture length simultaneously. In addition, as the time goes, the fracture propagation length contributed by the displacement cannot meet the needed fracture length of temporary plugging agent. Temporary plugging agent cannot exert diversion effect no matter how much it is. The displacement optimization under the field conditions by the optimization design model shows that the displacement shall be controlled lower than 3.0 m3/min in the stage of temporary plugging and higher than 6.0 m3/min in the stage of fracturing, which is the most suitable for diversion fracturing. The research results provide theoretical support the field application.