方深1井页岩气藏特大型压裂技术

摘要

Shale gas reservoir with low porosity,low permeability,developed fractures and other characteristics must be stimulated in order to achieve commercial development. Well Fangshen 1 is one of the key shale gas wells of Sinopec. According to the well conditions and technical characteristics of shale gas reservoir stimulation,large-scale fracturing technology with friction reducing fluid was applied. Fluid formula and proppant selection were optimized through experimental study. Fracturing parameters were determined through minifrac. Fracturing design was optimized accordingly. The application in Well Fangshen 1 was successful. The treatment fluid is 2 121 m3; accumulated proppant is 160 m3 and flowback rate is 83. 2%. The application in this well demonstrated that the friction reducing fluid can meet the requirement of shale gas reservoir stimulation because of its characteristics of no damage, low friction, low interfacial tension,and low flowback resistance. The stimulation experience in this well provides good references in later shale gas reservoir stimulation.%页岩气储层具有孔隙度小、渗透率低、裂缝发育等特点,需要进行压裂改造才能获得理想产能.方深1井是中国石化一口复查页岩气的重点井,根据适合页岩气储层压裂技术的特点及该井的具体情况,确定采用降阻水大型压裂技术对该井储层进行压裂改造.通过试验和理论分析,优选出了降阻活性水配方和支撑剂.通过小型压裂确定了压裂设计的关键参数,并进行了压裂优化设计.方深1井根据压裂设计进行了降阻水大型压裂施工并获得成功,该井施工用液2 121.0 m3,累计加砂1 60.0 m3,压后返排率达83.2%,取得了较好的试气效果.方深1井的成功压裂表明,降阻活性水压裂液具有无损害、低摩阻、低界面张力、低返排阻力的特点,既能满足压裂施工需求又适合页岩气藏低孔低渗的特点.该井压裂成功对今后页岩气储层的压裂改造具有较好的借鉴意义.