适合致密油藏的低伤害可回收清洁压裂液体系

Low Damage Recyclable Clean Fracturing Fluid System Suitable for Tight Reservoir

邓长生 赵有兴 苏明健 蔡永吉

DENG Changsheng ZHAO Youxing SU Mingjian CAI Yongji

为了降低致密砂岩油藏压裂施工的成本和环境污染风险，提高压裂液的利用效率，以脂肪酸、二甲氨基丙 二胺、二氯异丙醇、非离子表面活性剂、多组分有机溶剂等为原料，制得新型复合表面活性剂（GEMR-2），将其与 有机酸盐调节剂复配制得适合致密油藏的低伤害可回收清洁压裂液体系。室内对压裂液的携砂性、破胶性、对 岩心的伤害性、可回收等综合性能进行了评价，并成功进行了现场应用。结果表明，该压裂液体系的耐温抗剪切 性能良好，在80 ℃、170 s-1的条件下剪切120 min 后的黏度仍能达到50 mPa·s 以上。压裂液的携砂能力较强，并 且可以迅速破胶，破胶液的残渣含量低于1.5 mg/L，界面张力较低。该压裂液破胶后对储层天然岩心渗透率的 伤害率低于5%，具有低伤害的特点。使用破胶液重复配制的压裂液仍然具备较强的耐温抗剪切性能，具有良好 的可回收重复利用性能。在ZM-12 井使用低伤害可回收清洁压裂液体系的施工过程顺利，压裂增产效果显著， 现场返排液重复配液性能较好，节约了大量的水资源。

In order to reduce the cost and environmental pollution risk of fracturing operation in tight sandstone reservoir，and improve the utilization efficiency of fracturing fluid，a new composite surfactant（GEMR-2）was prepared by using fatty acid， dimethylaminopropylamine，dichloroisopropanol，non-ionic surfactant，multi-component organic solvent，etc. It was compounded with organic acid salt regulator to obtain a low damage recoverable clean fracturing fluid system suitable for tight reservoir. The comprehensive properties of fracturing fluid，such as sand carrying property，gel breaking property，damage to core and recyclability，were evaluated in the laboratory. Finally，the fracturing fluid was successfully applied in the field. The results showed that the fracturing fluid system had good temperature resistance and shear resistance，and the viscosity could still reach more than 50 mPa·s after shearing for 120 min at 80 ℃ and 170 s-1. The fracturing fluid had strong sand carrying capacity and could break the gel quickly. The residue content of the gel breaking fluid was less than 1.5 mg/L，and the interfacial tension was low. The damage rate of fracturing fluid to the permeability of natural core after gel breaking was less than 5% ，indicating low damage. The fracturing fluid repeatedly prepared with gel breaker still had strong temperature resistance and shear resistance，and had good recyclability. The construction process using low damage recyclable clean fracturing fluid system in ZM-12 well was successful. The fracturing stimulation effect was remarkable，the repeated liquid mixing performance of on-site flow-back fluid was good，and a great deal of water resource was saved.

10.19346/j.cnki.1000-4092.2022.04.005