有机硼锆交联剂的制备与延缓交联效果

Preparation of Organic Boron-Zirconium Crosslinker and the Effect of Retarding Crosslinking

胡世平 李建平 韩俊华 张云玲 段辉彬

HU Shiping LI Jianping HAN Junhua ZHANG Yunling DUAN Huibin

为获得耐高温、抗剪切性和延缓交联效果良好的交联剂，在80 ℃下，以柠檬酸、丙三醇、甲醛、三乙醇胺为配位体，氯氧化锆与硼砂为主要成分，合成了红棕色黏稠状的有机硼锆交联剂。优选了制备交联剂的最佳条件，研究了交联剂和调节剂加量对交联时间的影响，评价了冻胶的破胶性和耐温抗剪切性。结果表明，制备交联剂时，氯氧化锆与硼砂的最佳质量比为0.9～1.5；调节剂、交联剂与压裂液基液的最佳体积比为0.4:0.5:100，此条件下的交联挑挂时间为64 s；在瓜尔胶压裂液基液中加入0.001%～0.003%过硫酸铵，破胶时间为6～12 h，破胶液黏度与表面张力均符合行业标准要求；冻胶在140℃、170 s-1下经连续剪切90 min的黏度约100 mPa?s。该交联剂耐温抗剪切性和延缓交联效果较好，可满足大部分油气井压裂施工需要。图3表2参14

In order to obtain a crosslinker with good resistance of high temperature and shearing, and good effect of retarding crosslinking, an organic boron-zirconium crosslinker with certain viscosity and color of reddish brown was synthesized at 80℃, with citric acid, glycerol, formaldehyde, triethanolamine as the ligands, zirconium oxychloride and borax as the main components. The preparation condition of the crosslinker was optimized, the effect of the dosage of crosslinker and regulator on crosslinking time was investigated, and the performance of gel breaking and shearing resistance at high temperature about the gel was evaluated. The results showed that, in preparation of the crosslinker, the optimum mass ratio between zirconium oxychloride and borax was 0.9—1.5. The optimum volume ratio of regulator, crosslinker and fracturing base fluid was 0.4:0.5:100. On this condition, the crosslinking time with picking and hanging was 64 s. After adding 0.001%—0.003% ammonium persulfate in guar gum fracturing base fluid, the gel breaking time was 6—12 h, the viscosity after gel breaking and the surface tension conformed to the requirement of industry standard. The viscosity of gel remained 100 mPa?s after continuous shearing for 90 minutes at 140℃ and 170 s-1. The crosslinker had good performance on high temperature and shearing resistance and effect of retarding crosslinking, which could meet the need of the most oil and gas wells fracturing construction.