威远页岩气水平井钻井关键技术及发展方向

KEY TECHNOLOGY AND DEVELOPMENT DIRECTION OF HORIZONTAL WELL DRILLING IN WEIYUAN SHALE GAS RESERVOIR

威远页岩气示范区目前已进入规模开发阶段,区域地层可钻性差、页岩易碎易垮、井眼轨迹复杂等地质工程难点仍制约钻井周期的缩短,作业成本依然较高。随着勘探领域的拓展,边缘低压薄储层区、深部储层开发的配套技术亟需完善。为实现该区域高效率、高效益持续开发,开展了井眼轨迹、高性能钻井液、地质导向、水平井固井等技术的优化与集成,并研究试验了柴油基钻井液、高效滑动定向等低成本技术和自主旋转导向工具,在钻井技术进步和提速提效方面取得了显著成效,对其它页岩气区块钻井具有较好的借鉴意义。提出发展一趟钻钻井技术、完善深层页岩气和多储层立体开发配套工程技术思路,为下步攻关方向提供参考。

Weiyuan Shale Gas Demonstration Zone is currently at the stage of large-scale development while local geological engineering characteristics such as the complexity in lithology and brittle shale layers and difficulties in tracking reservoirs are restricting the shortening of drilling cycle and operating cost.With the expansion of exploration,the supporting technology of handling brittle edge zones and deep reservoir development needs to be improved.To achieve efficiency and sustainability of development,drilling techniques,including high-performance drilling fluid,geosteering,and horizontal well cementing,have been optimized and integrated.The researches progressing in diesel-base drilling fluid,sliding orientation and independent rotary steering tool have achieved significant effects on optimizing drilling techniques and efficiency,providing a reference to the extraction of shale gas in other areas.The idea of developing one-trip drilling technology,perfecting deep shale gas drilling and multi-layer shale development provides suggestions for the next research stage.