雄安新区D19井破碎热储层气举反循环钻进技术

Gas lift reverse circulation drilling technology for D19 well in broken thermal reservoir in Xiong’an New Area

D19井是雄安新区地热清洁能源调查评价项目的一个勘探孔,完钻井深4021.78 m,揭穿雾迷山组和高于庄组2个热储层。为应对热储层钻进严重漏失及保护热储层,选用了气举反循环钻进工艺。对深井气举反循环钻进设备进行配套,同时对双壁钻杆下深、风量等工艺参数进行了现场试验优选。针对钻遇复杂破碎地层时返水(渣)通道经常堵塞无法顺利钻进的问题,研制出了适宜于破碎地层气举反循环钻进的防堵进水接头,同时对进水(渣)口进行保护,有效地解决了破碎地层气举反循环钻进易堵塞的难题,顺利完成了钻探任务。完善了极破碎热储层气举反循环钻进工艺技术,为气举反循环钻进工艺在破碎热储层的应用和推广打下了基础。

Well D19 is an exploration hole in the geothermal clean energy survey and evaluation project in Xiong’an New Area.Drilling was completed at 4021.78m,penetrating two thermal reservoirs each in Wumishan Formation and Gaoyuzhuang Formation.Gas lift reverse circulation drilling was used to deal with serious leakage of the thermal reservoirs and protect the thermal reservoirs.The drilling equipment was selected,and the setting depth of the dual wall drilling string and the air volume were tested and optimized.In view of the drilling difficulty due to blockage in the return(cuttings)channel encountered in complex broken strata in the process of gas lift reverse circulation drilling,an anti-blocking inlet sub suitable for the reverse circulation drilling broken strata with protection of the inlet(cuttings)port have been developed.It effectively solved the blockage difficulty with gas lifting reverse circulation drilling in broken formation,and the drilling job was successfully completed.The gas lift reverse circulation drilling process for extremely broken thermal reservoir has been improved,which lays a foundation for the application and promotion of the gas lifting reverse cycle drilling process in broken thermal reservoirs.