支撑剂返排控制优化

在压裂过程中,支撑剂起着保持裂缝高导流能力的重要作用,同时支撑剂的回流也会影响压裂井的正常生产,损坏井下和地面设备,增加生产成本和修井费用。为保持支撑剂在裂缝中形成有效支撑,文中根据支撑剂在幂律流体中的沉降规律,结合颗粒干扰和壁面效应对沉降速度的影响,对沉降速度进行了修正,从而建立了支撑剂沉降距离的计算模型;根据临界流速,计算出支撑剂的临界返排量。应用该理论模型,结合实例进行优化设计分析,针对不同的井口压力选择对应的油嘴直径。计算结果表明,该模型对指导现场施工具有积极意义。

Control optimization on proppant spiting

In the process of fracturing,the proppant plays an important role in maintaining high conductivity.At the same time,the back flowing of proppant also affects the normal production of fractured well,damages the underground and ground equipments,adds more production and workover costs.In order to keep effective propping of proppant in the fractures,this paper established the settling velocity of proppant in power-law fluid,which considered the influence of particle interference and wall effect on the settling velocity being revised.The calculation model of settling distance was built.According to the critical velocity,the amount of proppant spiting was calculated.At last,taking a real well as an example,this paper optimized and designed the proppant spiting aimed at the nozzle diameter selected according to the different well head pressure.The calculation results show that the model proposed can effectively guide the site operation and has positive significance.