水平井液态药爆炸压裂工艺试验应用研究

TEST STUDY ON APPLICATION OF LIQUID EXPLOSIVES IN HORIZONTAL WELL FRACTURING

近几年利用爆炸法改善低渗油气田储层渗透性的技术研究日益受到重视。基于层内爆炸研究基础,通过实验研究了适用于低渗油层水平井液态药的爆炸压裂工艺设计及试验,并探讨了井下压力及温度的计算方法。研究表明,研制的1 500~3 500 m/s低爆速液态炸药,爆炸性能设计参数适中可控,可满足不同岩层爆炸压裂产生多裂缝缝网的工艺要求;低爆速爆燃降低了对油井地层的破坏性及爆炸后对岩层可能产生的压实作用;起爆条件约10 MPa、140℃,能满足现场安全使用条件。经在CZ44-58水平井现场试验应用初步取得工艺成功,起爆后井口最大压力约21 MPa,地震动态检测反响较大,爆炸作用明显。试验证明其设计原理可行,施工工艺安全可靠、具有可操作性,为低渗水平井油层压裂改造与开发提供新的技术途径。

In recent years,the explosion stimulation technology is being emphasized to improve the permeability of low permeability reservoirs. Based on the low permeability reservoir in-layer explosion technology,the liquid explosive fracturing process design and experiment for horizontal wells in low permeability reservoir was carried out,and the downhole pressure and temperature calculation method was discussed. Research shows that the explosion parameters of the developed 1500-3500 m/s low detonation velocity liquid explosives are moderate and controllable,can meet the process requirements of explosive fracturing for different rocks to generate multiple crack networks. The low detonation velocity reduces the damage to the formation around oil well and the compaction on the rock. The explosion initiation conditions are about 10 MPa and 140℃,ensuring a safe application conditions on site. The field test applications in horizontal well CZ44-58 have achieved preliminary success,after initiation the maximum wellhead pressure was about 21 MPa,the dynamic response of seismic test was relatively large. The test proves that the design principle is feasible, the application process is safe,reliable and operative. This technology provides a new technical way for fracturing in horizontal wells in low permeability reservoirs.