非均质低渗凝析气藏压裂后低效原因分析及改进措施研究

Reason analysis of inefficient fracturing in heterogeneous low permeability condensate gas reservoir and improvement measures

针对多数非均质低渗凝析气藏压裂后增产不明显甚至压裂后无效的问题,以某典型非均质低渗凝析气藏为例,对该凝析气藏的压裂设计、施工过程以及压裂后返排情况进行研究及总结,提出非均质凝析气藏压裂前应加强凝析气藏相变特征及储层非均质特征研究、科学选井选层、优化压裂规模、建立反凝析产能伤害评价模型并进行返排速度优选、合理控制生产压差等系列改进措施,以期为提高非均质低渗凝析气藏压裂增产效果提供借鉴。

Fracturing stimulation is often less effective or even ineffective in most of the heterogeneous low permeability condensate gas reservoirs.By taking a typical reservoir as an example,this paper studies the fracturing design,fracturing operation and flowback process,and proposes improvement measures,including enhancing research on phase behavior and reservoir heterogeneity,scientifically electing wells and layers,optimizing fracturing scale,optimizing flowback rate based on the model of deliverability variation caused by retrograde condensation,and controlling drawdown pressure.This study can be referred to improve fracturing stimulation effect for heterogeneous low permeability condensate gas reservoirs.