页岩气体积压裂滑溜水的研究及应用

Research and application of slick water for shale volume fracturing

关键词:  页岩  水力压裂  滑溜水  降阻剂  体积压裂

Key words:  shale  hydraulic fracturing  slick water  friction reducer  volume fracturing

摘要:

页岩储层需要采用大排量、大液量体积压裂才能获得工业气流,体积压裂要求压裂液具有可连续混配、低摩阻和高返排率性能。根据四川页岩储层特征和实验结果,研制了降阻性能高的聚丙烯酰胺降阻剂、高效复合防膨剂及微乳助排剂,研制了适于四川页岩气体积压裂的滑溜水。该配方在四川W、C区块直井8井次现场试验表明,降阻率为65.5%～68.3%； W区块平均返排率为46.19%,C区块返排率27.93%；累计增加井口测试产量6.24×10⁴～11.35×10⁴ m³/d。 

Abstract:

The shale reservoir requires volume fracturing with large displacement and large amount of fluid in order to obtain industrial gas flow. According to the volume fracturing requirement, the slick water should have low viscosity, low friction, high flowback, excellent antiswelling and good compatibility properties with reservoir. Combing the Sichuan reservoir characteristics with experimental result, we developed a polyacrylamide friction reducer, an efficient anti-swelling agent and microemulsion surfactant, and developed a liquid formulation fitting to Sichuan shale reservoir. The field tests of 8 wells in Sichuan W and C blocks showed that the excellent performance of friction reduction, whose friction reduction rate is 65.5% to 68.3%; the W block average flowback rate is 46.19%, the C block average flowback rate is 27.93%, and the cumulative test production reach 6.24×10⁴～11.35 × 10^4m3/d..