多羟基醇压裂液体系交联剂研究

针对常规胍胶压裂液对油气藏储层伤害的现状,提出一种有机硼交联多羟基醇压裂液体系.通过室内实验为该体系合成了有机硼交联剂的基础物S-BQ,其最佳原料配比n(多元醇A)∶n(硼酸)为8∶1,催化剂Na2CO3的质量分数为0.35%左右.针对S-BQ延迟交联时间过长的问题,经复配加入延迟调节剂和助溶剂,制得性能优良的有机硼交联剂FS-BQ.用该交联剂交联的多羟基醇压裂液具有很好的延迟交联特性和剪切稳定性.此外,该压裂液体系破胶彻底,残渣含量低,对油气藏储层伤害小,适合于超低渗透油气田储层改造.

Development of the crosslinker for polyhydroxy alcohol fracturing fluid system

In view of the problem of the reservoir damage of conventional gum gelling fracturing fluid,a organic boron crosslinking polyhydroxy alcohol fracturing fluid system is put forward,and the basic substance S-BQ of the crosslinker for the fracturing fluid system is prepared in laboratory.The best raw material proportion of S-BQ is the substance amount ratio of polyhydroxy alcohol A to boric acid of 8:1,and the mass fraction of catalyst Na2CO3 is about 0.35%.In view of too long delayed crosslinking time of S-BQ,by adding delay regulator and cosolvent to it,the crosslinker FS-BQ of excellent performance is prepared.The polyhydroxy alcohol fracturing fluid that is cross-linked by the crosslinker has perfect delayed gelation performance and good shear stability.Besides,the fracturing fluid system is of the advantages of gel broking completely,low residue content and little reservoir damage,and it is suitable for the improvement of ultra-low-permeability oil and gas reservoirs.