页岩储层增产改造工作液的研究与应用

页岩储层具有脆性高、天然裂缝或层理发育、低孔特征和极低的基质渗透率等特点,四川盆地页岩储层压裂改造主要采用滑溜水或"滑溜水+线性胶"的"大液量+大排量"体积压裂模式。针对页岩储层特点,结合改造工艺要求,形成了低摩阻、低伤害、高防膨率的SD常规滑溜水体系及SD页岩气井压裂用线性胶体系。同时为了提高页岩气开发过程中对水资源的使用效率,减少环境伤害,研发出一套高效抗盐滑溜水体系,实现了对返排液高效回收利用。现场应用表明,SD常规滑溜水及线性胶体系性能稳定,现场配制方便快捷,降阻效果明显,完全满足页岩气体积改造的要求;SD高效抗盐滑溜水体系实现了高矿化度下返排液的重复利用,满足了页岩气经济、环境保护的开发要求。 

Study and Application of Stimulation Fluid for Shale Reservoirs

Reservoir shalesare generally brittle and full of naturalfractures and beddings.They have low porosity and extremely low matrix permeability.Fracturing of shale reservoirs in the Sichuan Basin has been done mainly with slick water or "slick water plus linear gel" at high volume and high flow rate.Based on the nature of the shale reservoirs,an SD conventional slick water fracturing fluid and an SD linear gel for shale gas operation have been developed.The SD slick water fracturing fluid and the SD linear gel are of low friction,low damage to reservoir permeability and high inhibitive capacity.In field applications,the SD slick water fracturing fluid and the SD linear gel demonstrated good salt resistance,stable properties,and reduced flow friction.Both were very easy to prepare and the use of water was highly efficient because the fracturing fluid can be recovered for reuse.With the application of the SD slick water fracturing fluid,high salinity flowback fracturing fluids can be recovered for reuse,satisfying the needs for economic and environmentally friendly development of shale gas.