四川非常规气田开发主要钻井技术及其应用效果

随着油气勘探开发难度不断加大,尤其是近年来非常规气田的开发,定向钻井成为钻井主流技术,如何有效控制钻井成本和保护环境并防止井下事故的发生成为作业者必须面对的问题。为此,自2010年以来,在荷兰皇家壳牌集团(中国)四川非常规气项目50余井次的钻井工作中,运用了旋转导向技术、新型钻井液配方、钻井液回收技术和固控配套技术,取得了快速、安全、环保的应用效果,其中DXXX井应用旋转导向钻井,实现完钻井深5 729 m,水平段长1 418 m,钻井周期105 d,同比螺杆钻水平井节约时间65 d,钻井工程创下了该区新纪录。尤其是针对不同地层特点,兼顾环保要求,成功研制和应用了新型钻井液配方、固控和钻屑处理技术,取得了较好的环保效果。结论认为,上述配套技术的应用对提高钻遇产层成功率、提高钻井速度、缩短钻井周期、控制钻井成本、获得更好的经济效益和社会效益,具有重要的保障作用。

The Key drilling technologies in unconventional gas field development in Sichuan and their application effects

Directional drilling has become a main drilling technology with the increase of difficulties in oil and gas exploration and development, especially in the development of unconventional gas fields in recent years. The problems that operators have to face are how to control drilling cost, protect environment and prevent downhole accidents effectively. Since 2010, rotary steering technology, novel drilling fluid formula, drilling fluid recycle technology and solid control technology have been successfully applied by Royal Dutch Shell Group (China) to Sichuan unconventional gas project for over 50 well times, and have presented safety and environmental protection effects very soon. Among them, well DXXX is drilled by using rotary steering technology, and it sets up new drilling engineering record in this area, with TD 5729 m, horizontal section 1418 m long, and drilling cycle 105 days which is 65 days shorter than screw drilling cycle. And better environmental protection effects are realized with the development and application of novel drilling fluid formula and solid control and cutting processing technology which focus on not only different formation characteristics, but also environmental protection requirements. It is concluded that the new technologies play a vital role in enhancing pay zone targeting success ratio, increasing ROP, shortening drilling cycle and controlling drilling cost, so as to achieve greater economic and social benefits.