有机硼交联剂OBN - 90的合成与性能

Synthesis and performance on organic boron crosslinker OBN-90

史俊 李辉

西安石油大学化学化工学院，陕西 西安 710065

College of Chemistry and Chemical Engineering, Xi’an Shiyou University, Xi’an 710065, China

针对交联剂在井深约为2 000 ～ 3 000 m的井下压裂施工中的使用，通过室内实验合成了适用于此类油田的有机硼交联剂OBN - 90，其最佳原料配比为：n（烷基醇胺）∶n（硼酸）为2.3∶1。通过与羟丙基瓜尔胶压裂液交联实验，验证了OBN - 90在pH值约为12时对羟丙基瓜尔胶压裂液体系具有较好的缓释交联性能，温度在80 ～ 100 ℃时，有3 ～ 5 min的缓释交联特性。在170 s-1的剪切速率下，黏度能保持在50 mPa·s以上，且具有较好的耐温和剪切恢复性能。用双氧水作为该冻胶体系的破胶剂，其破胶水化的效果明显优于过硫酸胺。此外，该体系还具有较好的控制滤失能力，其滤失速度、初滤失量和滤失系数均低于普通硼酸盐交联压裂液。

In view of the crosslinking agent used in the depth of 2 000-3 000m during downhole fracturing, organic crosslinker
OBN-90 has been synthesisd by laboratory study, which can be applicable to this type of oilfields. The best synthesis
condition must be that the molar ratio of n(Alkanolamine) : n(boric acid) is 2.3 : 1. The experiments with the modified guar
fracturing fluid crosslinking confirmed that the OBN-90 has excellent release crosslinking capability and the pH is 12, the
temperature is 80 ~ 100 ℃, and has 3 ~ 5 min of sustained-release characteristics. In 170 s-1 of sheared rate, the viscitidy
can be maintained at more than 50 mPa•s, and has a excellent resistant-temperature capability and shear restore
performance. Used hydrogen peroxide as gel breaker in gelling system, the breaking effect is more superior than ammonium
persulfate. Meanwhile, the system also has a finer filtration loss controlling ability. Its filtration loss rate, initial filtration loss
and filtration loss coefficient are significantly lower than general borate crosslinked fracturing fluid.