文昌油田群珠江组储层保护修井液的优化研究与应用

Optimization of Workover Fluid for Reservoir Protection in Zhujiang Formation of Wenchang Oilfield Group

针对文昌油田群珠江组存在的黏土水化膨胀、分散运移、修井作业过程中漏失量大、修井液体系成本较高、修井后存在平均约5%的产能损失等问题,结合其储层敏感机理,分析造成储层伤害的原因,对现有的完井液与修井液体系进行了性能对比,结合修井液使用成本,对现有完井液体系进行了性能和成本优化。优化后的修井液体系防膨率得到提高、与地层水配伍性良好,岩心伤害渗透率恢复值达96.7%以上,具有优异的储层保护效果。优化的修井液体系现场应用后,成本较原来降低约48%,控制产油恢复期在3 d以内,和以往修井液配方相比,10口井累计节约成本200余万元,具有重要的推广应用价值。

There are many problems existed in Zhujiang Formation of Wenchang Oilfield Group,such as clay hydration expansion,dispersion and migration,large leakage during workover operation,high cost of workover fluid system,and an average productivity loss of about 5%after workover.In view of the above problems,and combined with the reservoir sensitivity mechanism of Zhujiang Formation of Wenchang Oilfield Group,this paper analyzes the causes of reservoir damage.By comparing the performance of existing completion fluid and workover fluid system,and combining the use cost of workover fluid,the performance and cost of the existing completion fluid system are optimized.The optimized workover fluid system has improved the anti swelling rate,achieving good compatibility with formation water.The recovery value of core damage permeability is more than 96.7%,which has excellent reservoir protection effect.After field application of the optimized workover fluid system,the cost is reduced by about 48% compared with original cost,and the recovery period of oil production is controlled within 3 days.Compared with previous workover fluid formula,the cumulative cost of 10 wells is saved by more than 2 million yuan,which has important promotion and application value.