深层高温高压储层酸压改造技术研究与应用

Research and application of acid fracturing technology for high temperature and pressure reservoir

四川盆地九龙山构造栖霞~茅口组储层具有高温,高压,裂缝较发育,横向连续性差,非均质性强等特点,常规酸压工艺适应性差,施工风险大。为提高酸压施工安全性及成功率,建立井周岩石受力模型精准预测破裂压力,采用“前置自生酸、加重酸酸压、多级交替注入、闭合酸”的酸压改造工艺,优选配套管柱及酸液体系,有效增加施工井底压力及酸液作用距离。现场试验结果表明:L004-6与L004-X2实际破裂压力与预测值相当,破裂压力预测模型准确度高,两口井改造后分别获气127.77×10^(4)m^(3)/d和131.17×10^(4)m^(3)/d,酸压增产效果显著,为后续工艺参数优化与区块天然气资源开发提供了有效支撑。

Qixia Maokou formation reservoir of Jiulongshan structure in Sichuan Basin has the characteristics of high temperature,high pressure,relatively developed fractures,poor transverse continuity and strong heterogeneity.The adaptability of conventional acid fracturing process is poor and the construction risk is high.In order to improve the safety and success rate of acid fracturing construction,establish the rock stress model around the well and accurately predict the fracture pressure,adopt the acid fracturing transformation process of"pre autogenous acid generation,weighted acid fracturing,multi-stage alternating injection and closed acid",optimize the supporting pipe string and acid system,and effectively increase the construction bottom hole pressure and acid action distance.The field test results show that the actual fracture pressure of L004-6 and L004-X2 is equivalent to the predicted value,the prediction model of fracture pressure has high accuracy,and the gas obtained by the two wells after reconstruction is 127.77×10^(4)m^(3)/d and 131.17×10^(4)m^(3)/d,with remarkable acid fracturing stimulation effect,which provides effective support for subsequent process parameter optimization and block natural gas resource development.