致密砂岩气钻完井技术进展及展望

Progress and prospect of tight sandstone gas well drilling and completion technologies

加快致密砂岩气(以下简称致密气)高效勘探和规模效益开发,对提高我国天然气自给能力,保障国家能源安全、实现“双碳”目标具有重要意义。为进一步促进致密气的规模增储上产,将资源量转化为储量、产量,在系统总结分析“十三五”期间致密气钻完井技术进展的基础上,对标分析了致密气钻完井技术面临的挑战,对“十四五”及中长期致密气钻完井技术的发展进行了展望分析。研究结果表明:①创新形成了致密气钻完井技术体系,主要包括:长水平段水平井快速钻井技术、大井丛工厂化钻井提速提效技术、小井眼钻完井技术、侧钻井技术、气体钻井技术等。②致密气水平井迈上5000m水平段新台阶,最长水平段长度达5256m,钻井时效逐年提升,保障了鄂尔多斯盆地、四川盆地致密气效益开发和持续上产。③“十四五”期间,持续提升大井丛工厂化钻完井作业水平,探索混合井组下更高效的批量化、标准化的作业模式;升级改造装备、配套关键工具,提升长水平段一趟钻比例;完善致密气小井眼钻完井配套技术,成熟区全面推广应用小井眼钻完井技术;加强老区致密气剩余气挖潜攻关,加快连续管侧钻技术、柔性钻杆径向钻孔研究与试验;探索气体钻水平井/侧钻水平井技术。结论认为,“十四五”及中长期,致密气仍是中国天然气增储上产的重点领域,致密气钻完井技术的不断发展和进步是确保致密气高效规模效益开发的关键。

Speeding up the efficient exploration and large-scale benefit development of tight sandstone gas(hereinafter referred to as tight gas) is of great significance to improving domestic self-supporting capacity of natural gas, ensure the national energy security and realize the goal of "carbon peak and carbon neutrality". To further promote the scale reserve and production increase of tight gas and convert resources into reserves and production, this paper systematically analyzes and summarizes the progress of tight gas well drilling and completion technologies during the 13^(th) Five-Year Plan. Based on this, benchmarking is carried out on the challenges to tight gas well drilling and completion technologies, and the development of tight gas well drilling and completion technologies during the 14^(th) Five-Year Plan and in the midium and long term is predicted. And the following research results are obtained. First, a tight gas well drilling and completion technology system is innovatively developed, mainly including fast drilling technology of horizontal wells with long horizontal sections, ROP and efficiency improvement technology of factory-like drilling of large well clusters, slim hole drilling and completion technology, sidetracking technology and gas drilling technology. Second, the horizontal section of horizontal tight gas wells has stepped up to a new level of 5 000 m, with the maximum length reaching 5 256 m. The improvement of drilling efficiency year after year ensures the benefit development and sustainable production of tight gas in the Ordos Basin and the Sichuan Basin. Third, it is recommended to continuously improve the factory-like drilling and completion level of large well clusters and explore a more efficient mass and standardized operation mode of mixed well groups;upgrade and transform equipment and supporting key tools to increase the proportion of onetrip drilling of long horizontal sections. It is necessary to improve the supporting technologies for small hole drilling and completion of tight gas wells and promote the application of small hole drilling and completion technology in mature areas;strengthen the researches on potential tapping of remaining tight gas in old areas and speed up the researches and tests on coiled-tubing sidetracking technology and radial drilling of flexible drill pipes;explore gas drilling horizontal wells/sidetrack horizontal well technologies. In conclusion, tight gas will still be the important field of natural gas reserve and production increase in China during the 14 th Five-Year Plan and in the midium and long term and the continuous development and progress of tight gas well drilling and completion technologies is the key to ensure the efficient and scale benefit development of tight gas.