合成聚合物XJJ-4耐高温压裂液室内研究

Study on the Synthetic Polymer XJJ-4 for High Temperature Fracturing Fluid

采用自制聚合物配制出了合成聚合物基高温压裂液研究了体系组成对压裂液性能的影响,考察了组成为:0.40%稠化剂XJJ-4+0.25%交联剂J-1+0.015%pH调节剂W-1+0.2%助排剂。压裂液体系的耐温抗剪切性、黏弹性、流变性以及破胶性。研究结果表明,该压裂液体系在150℃、170 s^(-1)下连续剪切2h后的黏度约120mPa·s,耐温抗剪切性良好;在线性黏弹区内,体系储能模量G′恒大于损耗模量G″,是典型的黏弹性结构流体;稠度系数(2.141 mPa·S^(0.476))较大,流变行为指数(0.476)较小,具有明显的非牛顿流体行为;加入0.01%破胶剂APS,在150℃下3 h完全破胶水化,破胶液黏度1.38mPa·s,残渣含量15 mg/L,且破胶液具有较低的表面张力(26.24mN/m)和界面张力(1.83mN/m),有利于压裂施工后破胶液顺利返排,降低对地层的伤害。

A kind of synthetic polymer-based fracturing fluid system was introduced,which was composed of 0.40%thickener XJJ-4,0.25%cross-linker J-1,0.015%pH regulator W-1 and 0.2%cleanup agent.The performance of heat resistant,shear resistant,viscoelasticity,rheological property and gel-broken fluid was studied.The last viscosity of the fracturing fluid was about120 mPa·s after shearing 2 hrs at 150℃ and 170 s^-1.The fracturing fluid system was resilient to heat and shear.In the linear viscoelastic region,the storage modulus G＇ was greater than loss modulus G＂,and it was a typical viscoelastic fluid.The consistency coefficient（2.141 mPa·s^0.476） was large,and the index of rheological behavior（0.476） was small,indicating obvious non-Newtonian fluid behavior.With adding 0.01%breaker APS,the gel was broken after 3 hrs at 150℃.The viscosity,residue content,surface tension and interfacial tension of the gel-broken fluid was 1.38 mPa·s,15 mg/L,26.24 mN/m and 1.83 mN/m respectively,which would decrease the damage to formation and flow back easily.