低渗透油田水力压裂垂直缝增产效果数值模拟评价

用三维三相全组份油藏数值模拟器对低渗透油田有水力压裂垂直缝井的自然能量衰竭式开采过程进行了预测 ,并与不压裂的自然能量衰竭式开采过程进行了比较 .结果表明 ,考察水力压裂垂直缝增产效果应从两个方面进行 ,即 :1 .瞬时地考察井的产量 ;2 .动态地考察生产过程 .水力压裂垂直缝在前期提高了井的产量 ,随着时间的进行 ,其效果逐渐减弱 ,最后消失 .这不仅仅是传统上认为的裂缝闭合造成的结果 ,而是因裂缝改变了渗流场造成的 ;水力压裂垂直缝提高了开采速度 ,但对采收率的影响微乎其微 ,利用物质平衡方法对其进行了分析 .水力压裂是改善低渗透油田生产效果的一种有效方法

Evaluation of Production Increasing Effect of Vertical Hydraulic Fractures in Low-permeability Oilfields by Numerical Simulation

The natural depletion process of the low permeability wells with vertical hydraulic fractures was predicted by a 3D 3P full compositional simulator. And by being compared with that of the low permeability wells without hydraulic fractures, it is thought that the vertical fractures can increase the output of the wells in the earlier stage, but the effect will gradually weaken and disappear at last. This is not only because the fractures gradually close, but also because they change seepage field. The vertical fractures only increase recovery rate, but the effect of them on recovery factor is little.