Project Title: Key Technologies and Applications for Integrated Transformation of Tight Oil and Gas Reservoirs Based on Digital-Intelligent Decision Methods

Participating Enterprises: Southwest Petroleum University
China National Petroleum Corporation Bohai Drilling Engineering Co., Ltd., Downhole Operations Branch
Tianjin Huizhu Petroleum Equipment Technology Co., Ltd.

Award Received: Scientific and Technological Progress Award

Project Number: ECF-2026-SYE-1030

Main Participants: Bai Tianzeng, Zhang Wei, Wang Xiaochao, Yang Xiaojiang, Kou Shuangyue, Ren Yongqiang, Wang Qiang, Li Jin, Jin Xianpeng, Yu Zhihai, Kan Zhengyu, Mao Jincheng, Wang Shiming, Wang Yufeng, Hu Yongqiang

Expert Review Comments:

This achievement treats fracturing, soaking and production as a coordinated design problem, recognizing the influence of post-treatment fluid exchange and production response on stimulation performance. Multiphysics modelling and soaking-parameter optimization are supported by temperature-resistant fluids, downhole tools and fracture monitoring. Applications across several oil-producing regions demonstrate the connection between analytical methods and field equipment. The principal value is a broader basis for stimulation design: more informed soaking decisions, better matching of fluids and tools to operating conditions, and improved post-treatment management. The approach provides a useful reference for developing integrated treatment programmes for comparable tight reservoirs.

Main Innovations:

1. Pioneered a full lifecycle THMC multi-field coupling theoretical system and targeted engineering optimization decision-making method for complex and tight oil reservoirs through the 'fracturing-soaking-production' approach. 2. Developed a VES clean fracturing fluid that withstands 180°C and an intelligent responsive strong associative fracturing fluid that withstands 140°C. The intelligent responsive strong associative fluid can handle salinity of 80,000–140,000 ppm, reduces static sand-settling rate by 95%, achieves an oil-washing efficiency of up to 93.56%, and solves the traditional problems of weak sand-carrying capacity, low seepage efficiency, and high residue damage in fracturing fluids. 3. Developed an integrated tool for sandjet perforation-fracturing-isolation that can handle 180°C and 90 MPa pressure difference, a purely electric-driven continuous mixing device for fracturing fluid with 20 m³/min mixing capability and pump pressure over 10 MPa, and a BH-SFM microseismic monitoring device for fractures with 1.86 μs synchronous error, monitoring depth of ≥5000 m, positioning error <10⁻⁷ s, and wide frequency range of 1 Hz–500 Hz. These innovations tackle the challenges of fine control in reservoir volume modification and real-time fracture monitoring and evaluation.

Main Uses and Technical Principles:

This project targets the efficient development of complex, tight oil and gas reservoirs. It addresses bottlenecks like the lack of a fully integrated pressure-soak-production process theory, insufficient fracturing fluid performance, and reliance on imported core equipment, by developing a complete set of key technologies. The technical principles are: pioneering a fully coupled flow-solid-thermal-chemical multi-physics model for the entire fracturing-soak-production process, establishing a dual-swelling clay constitutive model and full lifecycle numerical model, and creating an intelligent well-soaking decision method; developing a low-damage, high-oil-recovery fracturing fluid system that can withstand 140–180°C temperatures and 80,000–140,000 ppm salinity; and creating an integrated sand jet perforation-fracturing-isolation tool and microseismic monitoring system that can handle 180°C and 90 MPa pressure differences, enabling efficient multi-stage operations with a single tubing run and precise fracture monitoring, forming an integrated technology system covering theory, fluids, equipment, processes, and monitoring.