低摩阻超高温压裂液研究及应用

Study and application of low-friction high-temperature fracturing fluid

 肖兵 范明福 王延平 郭粉娟 赵莹 党昊

 中国石化中原石油工程有限公司井下特种作业公司，河南 濮阳 457164

 Downhole Special Service Company, Zhongyuan Petroleum Engineering Corporation Limited, SINOPEC, Puyang 457164, China

 针对常规压裂液耐温能力不足、交联时间短、施工摩阻高等问题，通过研制强延缓交联剂、温度稳定剂，优选稠化剂、pH调节剂、黏土稳定剂，开发了一套低摩阻超高温压裂液体系，形成3个高温（160，180，195 ℃）配方，并进行了流变性能、降阻性能、破胶性能及伤害性能的分析评价。结果表明：该体系可在不同温度点下交联，交联时间可控，并具有良好的抗剪切能力，195 ℃，170 s-1下剪切95 min后，黏度仍保持在50 mPa·s以上；破胶液残渣质量浓度为386 mg/L，对支撑剂充填层导流能力的伤害率为7.85%，滤液对岩心渗透率的损害率为19.20%，降阻率为55.34%，完全能满足超深高温储层大规模压裂的要求。此体系成功应用于塔河油田TKX井6 576.07～6 656.00 m井段，同等排量下的降阻效果明显优于常规压裂液。

 Aiming at the problems of insufficient temperature resistance, short cross-linking time and high frictional construction resistance of conventional fracturing fluid, an ultra-high temperature fracturing fluid system with low concentration and low frictional resistance was developed through the development of strongly-delayed cross-linking agent, temperature stabilizer, thickening agent optimization, ph regulator and clay stabilizer. Three high temperature formulations for 160, 180 and 195 ℃ were formed, and the rheological property, frictional resistance, gel breaking property and damage property of the system were analyzed and evaluated. The results show that: this system can be cross-linked at varied temperatures. Cross-linking time can be controlled and anti-shear ability is favorable. Viscosity can be still above 50 mPa·s with the residue content of the cracked liquid at 386 mg/L, the damage rate of the supporting fracture 7.85%, the core permeability damage rate of filtrate 19.20%, the resistance-reducing rate 55.34% after 95 min shear at 195 ℃, 170 s-1, meeting the requirement of super-deep high-temperature reservoir fracturing. This system has been applied successfully to TKX Well 6,576.07￣6,656.00 m of Tahe Oilfield. The resistance reduction effect of this fracturing fluid system is better than conventional fracturing fluid system at the same displacement.

10.6056/dkyqt201804027