地质工程一体化钻井技术研究进展及攻关方向——以四川盆地深层页岩气储层为例

为了安全高效地开发我国深层页岩气资源,迫切需要开展地质工程一体化钻井技术研究。为此,在阐述地质工程一体化钻井的思想和研究思路的基础上,系统总结了该研究领域的最新进展,然后针对四川盆地深层页岩气储层特征,指出了下一步的攻关研究方向。研究结果表明：①地质工程一体化钻井是指以地质研究为基础,有针对性地调整、优化钻井方案,实现安全高效钻井,同时,运用实钻井的数据资料及时修正地质模型,最终形成地质工程一体化安全高效钻井方案;②现有的地质建模技术难以精细描述四川盆地深层页岩气储层的空间展布特征;③储层非均质性强,应建立考虑页岩储层各向异性特征的钻柱系统动力学模型;④提升钻井液润滑性能和精准控制井眼轨迹是水平段钻柱降摩减阻的关键;⑤为了满足高效破岩的需求,需要开展非平面齿破岩机理系统研究;⑥井下机器人可以实现对钻压、钻速的智能控制,有望成为智能钻井的新方法;⑦井周岩体力学—化学破坏、页岩微裂缝面摩擦行为的研究,将是深层页岩井壁失稳机理研究的主要内容;⑧人工智能辅助地质导向技术与新型随钻测量工具的研发将是主要攻关方向。结论认为,我国地质工程一体化钻井技术研究已经取得了阶段性进展,但是针对四川盆地深层页岩气储层,还需要在精细地质建模、高效个性化钻头、智能钻井控制、高精度导向及绿色降阻防塌钻井液等方面加强技术攻关,才能最终形成适用于深层页岩气储层的地质—工程—生态一体化安全高效钻井技术。

Research progress and direction of geology-engineering integrated drilling technology: A case study on the deep shale gas reservoirs in the Sichuan Basin

In order to develop domestic deep shale gas resources safely and efficiently, it is in urgent need to study the geology-engineering integrated drilling technology. In this paper, the latest progress in the research field of geology-engineering integrated drilling is summarized systematically after the concepts and research ideas of geology-engineering integrated drilling are illustrated. Then, based on the characteristics of deep shale gas reservoirs in the Sichuan Basin, the research direction in the following stage is pointed out. And the following research results were obtained. First, geology-engineering integrated drilling is based on geologic study to adjust and optimize the drilling scheme specifically, so as to realize safe and efficient drilling. In the meantime, it makes use of actual drilling data to modify the geologic model, so as to finally provide a safe and efficient geology-engineering integrated drilling scheme. Second, the existing geologic modeling technologies can hardly precisely describe the spatial distribution characteristics of deep shale gas reservoirs in the Sichuan Basin. Third, the reservoirs are of strong heterogeneity, so it is recommended to establish a dynamic model of drilling string system considering the anisotropic characteristics of shale reservoir. Fourth, improving the lubricity of drilling fluid and controlling the borehole trajectory precisely is the key to reducing the friction and drag of drill string in the horizontal section. Fifth, in order to meet the demand of efficient rock breaking, it is necessary to carry out a systematic study on the rock breaking mechanisms of non-plane teeth. Sixth, downhole robot can control weight on bit (WOB) and rate of penetration (ROP) intelligently and it may be a new method of intelligent drilling. Seventh, the studies on the mechanical-chemical damage to circumferential rock and the friction behaviors on the plane of micro fracture will the main content to research the borehole instability mechanisms in deep shale. Eighth, the research and development of artificial intelligence aided geosteering technology and novel measurement while drilling tool is the main research direction. In conclusion, an important progress has been made in researching the geology-engineering integrated drilling technology at home. As for the deep shale gas reservoirs in the Sichuan Basin, however, it is necessary to strengthen the studies on high precision geologic modeling, efficient personalized bit, intelligent drilling control, high-accuracy steering and environmental drilling fluid of friction reduction and collapse prevention, so that the safe and efficient geology-engineering-ecology integrated drilling technology suitable for deep shale gas reservoirs can be developed ultimately.