西藏阿里复杂地层地热井钻井关键技术研究应用

Research and application of key technologies for geothermal well drilling in complex strata of Ngari， Xizang

摘要:

西藏阿里朗久地热田地热井施工过程中，遇到地层破碎、坍塌、井喷（涌水）发生早、泥浆护壁平衡地压钻进困难、技术套管临时止水难度大、闸板防喷器易结垢失灵、井口人员操作安全防护难保障等难题。通过研发应用井口防喷导流装置、技术套管双挂止水装置、高温井井口换阀装置，解决了钻井过程中遇到的难题，既能保证上部含水层地热水完钻开采又能钻穿深部地热层，实现了同一钻孔多层开采地热水的目的。

Abstract:

During the drilling of geothermal wells in the Langjiu Geothermal Field in Ngari， Xizang， multiple challenges were encountered such as fractured and collapsed strata， early water blowouts/gush， difficulties in maintaining pressure balance with mud wall protection while drilling， high difficulty in temporary water shutoff with intermediate casing， frequent scaling and malfunction of ram BOP， and inadequate safety protection for personnel at the wellhead. By developing and applying the wellhead blowout preventer diversion device， the dual-hanging water-shutoff device for intermediate casing， and the wellhead valve replacement device for the high-temperature wells， the above difficulties have been effectively addressed. It not only ensures the completion and production of geothermal water from shallow aquifers but also enables drilling through deep geothermal layers， achieving multi-layered geothermal water production with a single borehole.