川南页岩气体积压裂技术发展与应用

我国四川盆地页岩气资源丰富，经过10余年探索，中国石油在川南地区实现页岩气的规模效益开发，掌握了页岩气勘探开发核心技术，页岩气压裂理论、技术和方法从无到有，从单一到配套，实现了从跟跑到部分领跑的全面进步。2010年至今，川南地区页岩气压裂经历了先导试验、自主研发、系统完善、技术升级4个发展阶段，形成了以体积压裂工艺技术、体积压裂配套技术、压裂裂缝监测与压裂后效果评价技术、工厂化压裂技术为核心的3500m以浅页岩气水平井体积压裂技术体系。研究总结了现阶段页岩气压裂技术进展和应用成效，分析了已有技术的局限性、川南地区压裂难点，提出需要针对不同埋深的页岩储层地质特征开展针对性的压裂理论深化研究与技术攻关，需攻关3500m以浅老区提高采收率、3500m以浅新井提高产量和储量动用程度、3500m以深页岩气提高单井产量及复杂防控等领域，以支撑未来页岩气高效开发。

Development and Application of Shale Gas Volume Fracturing Technology in Southern Sichuan Basin

China’s Sichuan Basin is rich in shale gas resources. Following the exploration efforts for more than a decade, PetroChina’s shale gas fields in the southern region of Sichuan came under large-scale development with economic performance. PetroChina has owned the key technology of shale gas exploration and development. PetroChina has also developed a system of shale gas fracturing theories, technologies and methods and become a leader in some areas of the industry. Shale gas fracturing in the southern region of Sichuan has experienced four development stages – pilot experiment, independent research and development, perfection of the system, and technological upgrading. A volume fracturing technology system for 3500-meter shallow shale gas horizontal wells has been developed, which is focused on volume fracturing process technology, auxiliary volume fracturing technology, fractured seams monitoring and post-fracturing effect evaluation technology and factory-style fracturing technology. This paper studies and summarizes the shale gas fracturing technological progress and application results at the current stage, analyzes the existing technological limitations and fracturing bottlenecks in South Sichuan, and proposes to improve fracturing theoretical research to highlight the geological characteristics of the shale gas reservoirs with the different buried depths. It is of great urgency to improve the productivity of the shallow and old areas. As for shale gas buried less than 3500 meters, the efforts should be focused on improving production of shallow and new wells as well as the producing degree of the reserves. As for shale gas buried more than 3500 meters, it is necessary to improve the single-well production and guard against the complicated conditions, thus maintaining high-efficiency shale gas development in the future.