低吸附耐高矿化度滑溜水体系研制与现场应用

Preparation and Field Application of Slickwater System with High Salt Tolerance and Low Adsorption

马应娴 马乐瑶 郭建春 周 瀚 熊雨佳 陈晔希 车继明

MA Yingxian MA Leyao GUO Jianchun ZHOU Han XIONG Yujia CHEN Yexi CHE Jiming

为降低压裂用滑溜水对储层的吸附伤害和实现产出水直接配制，提高回收再利用率，基于耐高矿化度、低吸附的要求，通过引入极性阳离子片段设计并制备了一种高耐盐低吸附降阻剂NY，将NY与助排剂、黏土稳定剂等添加剂复配得到滑溜水体系，对滑溜水配方进行了优化，评价了滑溜水的综合性能，并在四川盆地页岩区块进行了现场应用。结果表明，降阻剂NY的耐盐降阻性能良好，在高矿化度（≤300 g/L）下的降阻率大于70%，并与各添加剂的配伍性良好。滑溜水的耐盐降阻性能良好，在矿化度为0数 300 g/L的条件下，滑溜水体系的起黏时间均小于60 s，表观黏度为1数 3 mPa·s，表面张力均小于30 mN/m，防膨率均大于80%，页岩吸附量≤3.66 mg/g，各项指标均满足行业标准与现场压裂需求。现场实施8口井，施工成功率100%，产出水重复利用率100%。与普通耐盐滑溜水相比，该滑溜水吸附性和对储层的伤害低，液体综合成本降低17%，单井产量提升44%，现场应用效果显著。

In order to prepare slickwater with produced water directly and simultaneously reduce its adsorption damage to reservoir， a drag-reduction agent called NY with high salt tolerance and low adsorption was synthesized by introducing polar cation fragments. Corresponding slickwater system was compounded with NY and other additives，including clean-up additive and clay stabilizer. The formula of slickwater system was optimized by evaluating its comprehensive performance. Finally，the slickwater system was applied in the shale block of Sichuan basin. The experiment results showed that NY had high salinity tolerance and drag reduction， with drag reducing rate over 70% in high salinity condition（≤300 g/L），and exhibited good compatibility with other additives. The corresponding slickwater system also showed high salinity tolerance and drag reduction. When the salinity was 0—300 g/L，the sticky time of slickwater system was shorter than 60 s，together with apparent viscosity of 1—3 mPa·s. Meanwhile，the surface tension was less than 30 mN/m，the anti-swelling rate exceeded 80% and the shale adsorption capacity was less than or equal to 3.66 mg/g，which completely satisfied the requirements of industry standard and field operation. The application of slickwater system showed that both of the success rate of fracturing operation and reuse rate of produced water were 100% in 8 wells. Compared with conventional slickwater system，this novel slickwater system had low adsorption and reservoir damage. Meanwhile，the overall liquid cost reduced by 17% and the production rate per well increased by 44%，indicating remarkable results were achieved in field application.