BFD低伤害油层封窜剂的应用

APPLICATION OF LOW DAMAGING CHANNELING SEALING AGENT BFD IN PAY ZONE

郭建华 甄立杰 刘云飞 梁志红 白文科 韩敬 冯瑞林

中原石油勘探局钻井工程技术研究院, 河南濮阳 457001 华北油田公司, 河北任丘 062552

针对中原油田油水井固井水泥环窜漏问题,研制出BFD化学封窜剂。该封窜剂由20%~30%网架结构剂、60%~70%胶结材料和5%~10%膨胀剂组成。运用模拟井况封堵模型,评价了BFD挤入深度、封堵强度、流变性和初凝时间等性能,并分析了挤注压力、温度对挤入深度和封堵强度的影响,研究了封堵强度在封堵层和井筒内的变化规律。试验结果表明,BFD在封住油水井水泥环窜槽的前提下对油层伤害小,挤入油层深度0.3~0.5m,通过重炮可解除对油层污染,封堵强度不小于25MPa,初凝时间不小于6h。施工安全性高,流变性、稳定性好,适用于30~150℃封堵油水井管外窜槽、封油井底水和全封再射作业。现场应用12井次,成功率100%,有效率95%。

A chemical channeling sealing agent BFD is developed to solve the problem of channeling through cement sheath in Zhongyuan. This agent is composed of 20% to 30% of net-bridging agent, 60% to 70% of gelling material and 5% to 10% of swelling agent. A simulating sealing and plugging model was established, and it was used to evaluate the squeezing depth, sealing strength, rheology and initial setting time of BFD, while the influence of squeezing pressure and temperature on squeezing depth and sealing strength, as well as changing tendency of sealing strength in the sealing zone and borehole were investigated. Test results showed that it has minimum formation damage; the squeezing depth is 0.3 to 0.5 m, which can be eliminated through perforating; its sealing strength is 25 MPa or higher, and the initial setting time is 6h or longer. It also has such advantages as safe operation, good rheology and stability, simple field operation, etc., and it is suitable for sealing the external casing channeling in 30 to 150℃, sealing the bottom water in the pay zone and full-sealing reperforating operation. This agent has been field used for 12 times, with an operation success rate of 100% and efficiency rate of 95%.

10.3969/j.issn.1000-7393.2004.05.008