苏里格二三类储层压裂配套技术优化与应用

Optimization and application of fracturing matching technology for classⅡandⅢreservoir in Sulige

为进一步降低压裂液对储层伤害,通过体系优化、现场试验开发出了3种低伤害压裂液体系,并成功推广应用。实验结果表明:与常规胍胶压裂液相比,低伤害胍胶体系残渣降低20%以上,对岩心伤害率降低30%以上;一体化压裂液残渣含量仅80~100 mg/L,对岩心伤害率为15%~18%,并满足连续混配和返排液重复施工需求;通过交替变黏、体系组合形成的“组合压裂液”体系,前置液残渣含量降低60%左右,配合“多尺度支撑剂组合+高排量大规模注入”实现缝网的复杂化和高效连通。为降低水锁,提高返排率,研发了微乳液助排剂,通过数学模型优化形成了精细液氮伴注工艺,液氮使用量降低10%左右,助排剂用量降低12%,返排率提高7%左右,实现“快压快排”。通过多元暂堵材料的优化组合形成了复合暂堵工艺,并100%成功应用于非均质储层精细化改造。上述压裂配套技术都取得了良好的应用效果,成为苏里格二三类储层高效开发重要技术之一。

In order to further reduce the damage of fracturing fluid to reservoir,three low damage fracturing fluid systems have been developed through system optimization and field tests,then applied successfully.Compared with conventional guar gum fracturing liquid,the residue of the low-damage guar gum system is reduced by more than 20%,and the damage rate of the core is reduced by more than 30%.The residue content of integrated fracturing fluid is only 80~100 mg/L,and the core damage rate is 15%~18%,which can meet the requirements of continuous mixing and flowback fluid recycling.Through the"combined fracturing fluid"system formed by alternating viscosity and system combination,the content of pre-fluid residue is reduced by about 60%.In combination with"multi-scale proppant combination+large volume flow injection",the fracture network is complicated and efficiently connected.In order to reduce water lock and improve the flowback rate,the microemulsion cleanup additive was developed and a fine liquid nitrogen injection process was formed through mathematical model optimization,the usage of liquid nitrogen decreased by about10%,and the cleanup additive decreased by 12%,the flowback rate increased by about 7%,and realizing"rapid fracturing and rapid drainage".The composite temporary plugging technology was formed through the optimized combination of multiple temporary plugging materials,and it was 100%successfully applied to the refinement modification of heterogeneous reservoirs.The above-mentioned fracturing matching technologies have achieved good application effects and become one of the important technologies for the efficient development of classⅡandⅢreservoirs in Sulige.