径向钻孔在体积压裂井中的应用

Application of Radial Drilling Process in Volume Fracturing Wells

非常规能源地质储量巨大,有效开发必须通过体积压裂技术使人工裂缝复杂化。但由于体积压裂对储层工程品质要求较高,往往井周地应力差大导致人工裂缝复杂程度不够,使得压裂效果差。通过分析前人对井周裂缝起裂偏转的研究,利用ABAQUS数值模拟径向钻孔孔眼诱导应力场,发现多孔下井周应力场发生逆转,有利于压裂裂缝复杂化。并通过大型真三轴物模实验对这一理论进行验证,确定了一定夹角的多径向孔眼有利于人工裂缝复杂化。本文对指导非常规油藏体积压裂井的工艺选择,具有十分重大意义。

Unconventional energy geological reserves are huge, and in effective development of unconventional energy geological reserves, artificial fractures must be complicated by stimulated reservoir volume fracturing. Volume fracturing has high requirement for reservoir engineering quality, and the complexity of artificial fractures is not enough due to the large difference in formation stress around the well, so the fracture effect is poor. Based on previous studies on fracture initiation and deflection around wells, ABAQUS was used to simulate the induced stress field in radial boreholes, it was found that the stress field around the well under wells was reversed, which was helpful to complicate the fracture. This theory was verified by large-scale true triaxial physical model experiments. It was determined that multiple radial perforations with a certain angle were conducive to the complexity of artificial fractures.