水平井压裂后焖井技术的研究

Study on Shut-in Technology After Horizontal Well Fracturing

非常规油气藏开发通常采用大液量、大规模水平井分段压裂,常规油藏的快速返排方式已经不适用于此。从现场实施经验来看,适当的焖井可以辅助提高非常规油藏压裂效果。本文研究了压裂液进入储层焖井所产生应力场、温度场的变化;建立起脆性-低渗岩心的渗吸实验模型,验证了适当的焖井时间有利于压裂液与储层流体发生渗吸交互。根据实验结果,指导水平井压裂后焖井制度的建立,提高水平井最终单井产能。

The development of unconventional oil and gas reservoirs usually uses large-volume, large-scale horizontal well staged fracturing process. The rapid flowback method of conventional reservoirs is no longer suitable for this unconventional oil and gas reservoirs. From field implementation experience, proper shut-in can help improve fracturing effect in unconventional reservoirs. In this paper, the changes in the stress field and temperature field in the shut-in process after fracturing fluid entering the reservoir were studied. The experimental model of brittle-low-permeability core was established to verify that the appropriate shut-in time is beneficial to that the fracturing fluid and reservoir fluid occurs infiltration interaction. The experimental results can guide the establishment of shut-in system after horizontal well fracturing and increase the final single well productivity of horizontal well.