Li Xianzheng, Pan Chunfu, Chen Hao, Zhang Zheng, Ning Kun
China National Oil and Gas Exploration and Development Company Ltd., Beijing 100034, China.
CNPC Engineering and Technology R&D Company Limited, Beijing 102206, China.
ACS Omega. 2025 Feb 20;10(8):8281-8291. doi: 10.1021/acsomega.4c10023. eCollection 2025 Mar 4.
The development of deep oil and gas resources faces the challenge of high-temperature environments, where the performance of traditional fracturing fluids is limited. Therefore, there is an urgent need to develop fracturing fluid systems capable of withstanding high-temperature (up to 200 °C) and high-salinity (up to 45 g/L NaCl and multivalent ions) environments. This study explores the preparation and performance evaluation of a novel high-temperature (up to 200 °C) and salt-resistant (up to 45 g/L NaCl and multivalent ions) hydrophobically associated polymer fracturing fluid, focusing on its thickening mechanism and stability under extreme reservoir conditions. Key equipment used includes a rheometer for viscosity measurements and an environmental scanning electron microscope for microstructure observation. The base fluid maintained an apparent viscosity of 32.4 mPa·s at 200 °C, demonstrating excellent thermal stability. Long-term evaluations showed a viscosity retention rate of 94.9% after 90 days in high-salinity conditions, indicating outstanding durability. Sand-carrying tests revealed ceramic grain settling rates below 0.48 cm/min, confirming strong suspension capability. The fracturing fluid system exhibited low formation damage rates of 16.85% and minimal proppant pack damage, with a conductivity reduction of only 20.08%, both well below industry standards. These findings provide technical support for efficient fracturing operations in deep and ultradeep wells, particularly in environments with temperatures up to 200 °C and salinities exceeding 45 g/L NaCl, contributing to the development of fracturing fluids for such challenging conditions.
深层油气资源开发面临高温环境的挑战，传统压裂液在这种环境下性能受限。因此，迫切需要开发能够耐受高温（高达200℃）和高盐度（高达45 g/L氯化钠及多价离子）环境的压裂液体系。本研究探索了一种新型耐高温（高达200℃）和耐盐（高达45 g/L氯化钠及多价离子）的疏水缔合聚合物压裂液的制备及性能评价，重点关注其在极端储层条件下的增稠机理和稳定性。所使用的关键设备包括用于粘度测量的流变仪和用于微观结构观察的环境扫描电子显微镜。基液在200℃时的表观粘度保持在32.4 mPa·s，显示出优异的热稳定性。长期评估表明，在高盐条件下90天后粘度保留率为94.9%，表明具有出色的耐久性。携砂试验显示陶瓷颗粒沉降速率低于0.48 cm/min，证实了强大的悬浮能力。该压裂液体系的地层伤害率低至16.85%，支撑剂充填损伤极小，导流能力降低仅20.08%，均远低于行业标准。这些研究结果为深层和超深井的高效压裂作业提供了技术支持，特别是在温度高达200℃、盐度超过45 g/L氯化钠的环境中，有助于开发适用于此类具有挑战性条件的压裂液。
