高矿化度水基压裂液稳定剂的研制及应用

Development and Application of High Salinity Water-based Fracturing Fluid Stabilizer

杨文轩 管保山 梁 利 刘玉婷 卢新卫

YANG Wenxuan GUAN Baoshan LIANG Li LIU Yuting LU Xinwei

为减少高矿化度水对压裂液性能的影响，用三聚氯氰与亚氨基二乙酸二钠制备的三聚氰胺六乙酸（ELX）作为稳定剂螯合高矿化度水中的钙镁离子，改善海水及高矿化度水配液问题。研究了 ELX对金属离子的螯合能力、对高矿化度水的稳定效果及对羟丙基瓜尔胶压裂液性能的影响。结果表明，ELX产率可达 72%。ELX与大 多数金属离子有较好的螯合效果，其与 Mg2+、Ca2+、Cu2+、Fe3+的螯合值为 150～ 350 mg/g。加入 0.9%和 5%的 ELX可分别使高矿化度模拟水和模拟海水保持澄清。ELX与羟丙基瓜尔胶的配伍性良好，可改善基液黏度和压裂液交联性能；压裂液耐温耐剪切性良好；压裂液可在2 h内破胶，破胶液具有较低的表面和界面张力，残渣量及岩心基质渗透率的损害率与清水相当，符合施工要求。将ELX用于京x井现场压裂液配液，采用高矿度水基压裂液压裂施工后产油8.9 t/d。ELX可以用于淡水缺乏的海水、深层水、地表高矿化度水压裂，节约作业成本。图3表1参17

In order to reduce the effect of high mineral water on the performance of fracturing fluid and improve the mixing problem of seawater and high salinity water，melamine hexa-acetic acid （ELX） was synthesized by cyanuric chloride and disodium iminodiacetate which was used as a stabilizer to chelate calcium and magnesium ions in high salinity water. The chelating ability of ELX for metal ions，the stabilizing effect on high salinity water，and the effect on the performance of hydroxypropyl guar fracturing fluid were studied. The results showed that the synthetic yield of ELX could reach 72% . The chelation value between ELX and metal ions，such as Mg2+，Ca2+，Cu2+ and Fe3+ was 150—350 mg/g，showing good removal effect for most metal ions. The addition of 0.9% ELX could keep the high salinity water clarified，and adding 5% ELX could keep the seawater clarified. ELX and hydroxypropyl guar gum had good compatibility，which had a good improvement effect on the viscosity of base fluid and the cross-linking performance of fracturing fluid. The fracturing fluid had a good temperature and shear resistance. The gel was broken within 2 hrs，maintained the lower surface and interfacial tension of broken fluid. The residue amount of broken fluid and damage rate of core matrix permeability were equivalent to that of clean water，which satisfied the construction requirements. Field trials with ELX were successfully conducted and initial production after fracturing operation by high salinity water-based fracturing fluid was 8.9 t/d. Stabilizer ELX was suitable for hydraulic fracturing of seawater，deep water and high salinity surface water in fresh water scarcity area，which saved operating costs.