低温配液用交联剂的合成与评价

Synthesis and evaluation of a crosslinking agent suitable for cryogenic liquid mixing environment

为解决低温环境下压裂施工中交联剂结冻、失活、难交联的问题,通过在压裂液中引入一种低温活化剂C-1,并制备了一种适用于低温配液环境的交联剂YZ-1。通过实验确定最优方案:m(氧氯化锆)∶m(乙二醇)∶m(丙三醇)∶m(柠檬酸)∶m(盐酸)∶m(去离子水)=1∶1.5∶1∶0.5∶0.1∶6,反应温度为90℃,反应时间为3 h。冰点测定实验表明,乙二醇加量在15%时交联剂的冰点下降至-15.43℃,满足低温下不结冰、稳定存放;携砂和破胶实验表明在低温环境下的交联和携砂效果较好、破胶彻底,满足低温压裂施工要求;压裂液在剪切速率为170 s^-1、温度90℃、120 min后粘度还保持在90 mPa·s,抗剪切性较强。

In order to solve the problems of freezing,deactivation and difficult crosslinking of crosslinking agent in cryogenic fracturing operation,this paper introduced a kind of low-temperature activator C-1 into fracturing fluid and prepared a kind of cross-linking agent YZ-1 which is suitable for low-temperature compounding environment.The optimal solution was determined through experiments:m(zirconium oxychloride)∶m(glycol)∶m(glycerol)∶m(citric acid)∶m(hydrochloric acid)∶m(deionized water)=1∶1.5∶1∶0.5∶0.1∶6,the reaction temperature was 90℃,the reaction time was 3 h.The freezing point determination experiment shows that the freezing point of the crosslinking agent drops to-15.43℃when the amount of glycol is added at 15%,which meets the requirement of non-freezing and stable storage at low temperature.The results of sand carrying and breaking experiments show that the crosslinking and sand carrying effect is better in low temperature environment,and the glue breaking is complete,which meets the requirements of low temperature fracturing.The viscosity of fracturing fluid remained at 90 mPa·s after the shear rate was 170 s-1,the temperature was 90℃,and the temperature was 120 min.