塔河油田靶向压裂预制缝转向技术模拟研究

Simulation Study on the Range of Diversion in Targeted Fracturing of Prefabricated Fractures in the Tahe Oilfield

房好青 赵兵 汪文智 周舟

FANG Haoqing ZHAO Bing WANG Wenzhi ZHOU Zhou

中国石化西北油田分公司石油工程技术研究院，新疆乌鲁木齐 831000 油气资源与探测国家重点实验室（中国石油大学（北京）），北京 102249 中国石油大学（北京）石油工程学院，北京 102249

Petroleum Engineering Technology Research Institute, Sinopec Northwest Oilfield Company, Urumqi, Xinjiang, 830011, China State Key Laboratory of Petroleum Resources and Prospecting (China University of Petroleum(Beijing)), Beijing, 102249, China College of Petroleum Engineering, China University of Petroleum(Beijing), Beijing, 102249, China

塔河油田超深油气资源主要储存于碳酸盐岩天然裂缝、孔洞中，应用预制缝靶向压裂技术可以控制裂缝转向，提高油气产量。采用修正降阻比法计算管柱沿程摩阻，结合裂缝不稳定渗流理论计算缝内压力变化，利用位移不连续法计算裂缝转向距离，建立了裂缝扩展一体化模型。计算分析了缝洞型碳酸盐岩含有预制缝的靶向压裂裂缝扩展方向角度和扩展延伸长度等参数，并将施工参数与压裂裂缝转向距离进行关联，采用有限元法及物理模拟试验进行准确性验证。研究结果表明，压裂液黏度、预制缝角度、地应力差和地层岩石弹性模量等参数与压裂裂缝转向距离呈负相关关系；预制缝长度与裂缝转向距离呈正相关关系；施工排量需要优选，才能得到最优转向距离。靶向压裂预制缝转向技术的模拟研究结果，为塔河油田超深碳酸盐岩储层缝洞储集体的高效开发提供了理论指导和数据支持。

Oil and gas resources of the ultra-deep carbonate reservoirs in the Tahe Oilfield occur mainly in natural fractures and cavities, and the application of a targeted fracturing technology for prefabricated fractures can control the fracture diversion and improve oil and gas production. By utilizing the corrected resistance reduction ratio method to calculate string resistance, combining the unstable seepage theory to calculate pressure change in a fracture, and applying the displacement discontinuity method to calculate fracture propagation and diversion, it is able to establish the integrated model of fracture propagation. Through computational analysis of parameters such as the fracture propagation direction/angle and extension length of prefabricated fracture-bearing targeted fracturing, and correlating the pumping parameters and the diverting distance of hydraulic fracture, the accuracy and validity of this model are validated by virtue of finite element method and physical simulation experiments. The study results showed that the parameters of fracturing fluid viscosity, prefabricated fracture angle, in-situ stress difference and formation rock elastic modulus are negatively correlated with the diverting distance of hydraulic fracture. In this case, the length of prefabricated fracture is positively correlated with the diverting distance; the preferable pumping flow rate shall be adopted to achieve the optimal diverting distance. The simulation results of targeted fracturing prefabricated fracture diverting technology provided the theoretical guidance and data support for the efficient development of ultra-deep carbonate fracture and cavity reservoirs in the Tahe Oilfield.

国家科技重大专项“靶向酸压工艺技术研究”（编号：2016ZX05014-005-005）、国家自然科学基金青年项目“碳酸盐岩储层孔洞与水力裂缝扩展相互作用的力学机理研究”（编号：51704306）联合资助

https://doi.org/10.11911/syztjs.2019048