高压涌水及高含硫化氢页岩气井绳索取心钻进技术

Wire-line Core Drilling Technology in Shale Gas Wells with High Pressure Gushing Water and High H_2S Content

页岩气调查井荥地1井设计井深1600 m,钻探施工过程中发现多个高应力涌水破碎带,最大涌水量达135m^3/h,井口压力达2.5 MPa;并且地层水中溶解有硫化氢,从涌水中挥发出来的硫化氢气体最大含量达100 ppm;水温较高,在1300 m处涌水温度达到50℃;这些问题给施工带来了极大的困难,并增加了安全风险。针对以上问题,介绍了钻井过程中所采取的注水泥浆堵水技术、高密度钻井液平衡钻进技术、多级套管固井技术,并总结了每种技术的特点,为川西南地区以后的页岩气调查井钻探工作提供参考。

The designed depth is 1600 meters for the shale gas survey well Yingdi - 1. During the construction process, several high stress water gushing fractured zones were encountered, the largest watering quantity was 135m3/h and wellhead pressure was up to 2. 5MPa; there was hydrogen sulfide dissolved in formation water, the highest content of hydrogen sulfide gas escaped from the gushing water was up to lOOppm; the water temperature is high up to 50℃ in gushing spot at 1300 meters depth, these difficulties brought safety risk to the construction. In view of the above, this paper introduces water plugging technology by cement slurry grouting, balanced drilling technology with high density drilling fluids and multistage casing technology for well cementing used in drilling process and summarizes the characteristics of each technology, which can be reference for the shale gas investigation well drilling construction in Southwestern Siehuan.