工程因素对页岩气产量的影响——以北美Haynesville页岩气藏为例

我国页岩气开发尚处于前期探索阶段，分析国外成功的开发案例具有重要的借鉴作用和参考价值。在对北美Haynesville 页岩气藏生产数据进行统计和分析的基础上，总结了工程因素对该页岩气藏开发的影响规律。结论认为：页岩气井水平段长度、压裂级数、加砂量、油嘴尺寸、井底压力和是否采取重复压裂施工对累积产量有显著影响；水平段长度在1 500~1 650 m之间、压裂级数12~17级、加砂量1 500~3 000 t、油嘴尺寸8~9 mm为该地区常用且效果较好的设计方案；井底压力高的区域页岩气产量相应较高，这与井底超压改善页岩脆性、优化压裂效果有关；重复压裂能够显著提高页岩气总产量，作业时机的选择与增产效果关系密切。

Influences of engineering factors on shale gas productivity: A case study from the Haynesville shale gas reservoir in North America

Shale gas development in China is still in the exploration stage so we need to learn from good experiences and successful cases from abroad.Therefore,based on the statistical analysis of the production data of the Haynesville shale in North America,the influencing law of engineering factors on the development of such shale gas reservoir is summarized as follows.(1) All the factors like horizontal well length,number of fracture stages,proppant volume,choke size for production,bottomhole pressure,and whether to take re-fracture construction,exert significant influence on the accumulated productivity of a shale gas well.(2) In the recommended scheme designed and adopted in this area with good results,horizontal well lengths are 1500-1650 m,number of fracture stages are 12-17,proppant volumes 1500-3000 tons,and choke sizes 8-9 mm.(3) The shale gas well production is high at the area with high bottomhole pressure,which is related to overpressure improving gas shale’s brittleness and sharpening fracturing effect.(4) The total production can be significantly increased by re-fracturing and the increase of production is highly associated with the operation timing.