一种酸性压裂液用交联剂ZOC-1的制备及室内评价

Preparation and Laboratory Evaluation of a New Cross-Linking Agent ZOC-1 for Acid Fracturing Fluid System

制备了一种针对酸性压裂液体系的高温延缓型有机锆交联剂ZOC-1,考察了合成工艺中不同因素对ZOC-1性能的影响,确定了ZOC-1的最佳合成工艺:氧氯化锆5%,配体20%,水、甘油质量比0.3,pH值2～3,反应温度50～55℃,反应时间4～5 h。将羧甲基瓜尔胶溶液与ZOC-1按质量比100∶0.3交联,交联时间为50～92 s,压裂液耐温性可达100℃。在100℃、170 1/s下连续剪切60 min,冻胶表观黏度可保持在80～90 mPa.s。携砂比为35%时,压裂液的沉降速度为0.285 cm/min。破胶液黏度最大值为4.8 mPa.s,且对储层伤害小,适用于100℃以下超低渗透油气田施工要求。

A type of zirconium-organic cross-linking agent,ZOC-1,with excellent temperature resistance and delaying performance was prepared for acid fracturing fluid system.The factors influencing on the synthetic process of ZOC-1 were investigated and the optimum condition was obtained as follows： 5% zirconium oxychloride,20% ligands,a combination of water and glycerin in mass ratio 0.3,2—3 pH value,50—55℃ reaction temperature,4—5 h reaction time.Carboxymethyl guar gum solution reacted with ZOC-1 in mass ratio 100∶ 0.3 with cross-linking time 50—92 s and the temperature resistance of the fracturing fluid reached to 100℃.The viscosity of gel fluid maintained in range 80—90 mPa · s at 100 ℃ and 170 1/s with shearing time 60 min.The static sand-carrying speed was of 0.285 cm/min when the sand-carrying ratio was of 35%.The biggest viscosity of broken fluid was of 4.8 mPa · s,which had low damage to the reservoir and could satisfy the fracturing operation requirement for the reservoirs below 100℃.