复合材料封堵技术在外漏井治理施工中的应用

Application of composite material plugging technology in treatment of casing external leakage well

大庆油田经过多年开发,进入高含水中后期,受地层水腐蚀、射孔、修井、压力异常、套管变形、套损、固井质量下降等因素影响,油层套管发生破损、管外窜槽等问题日趋严重,浅层外漏井逐渐增多,造成环保隐患。针对这一问题,开展了复合材料封堵技术的研究,采用机械封堵和化学封堵技术相结合的方法,建立从建网、封堵到封口的流程,解决了封堵过程中可能遇到的套管外堵剂无效注入量大、环空内混砂混泥或水侵浓度降低、固结水泥塞柱过高造成拔不动、堵剂浪费、固结强度不够导致封堵失效、工艺效率低等问题。2022年在A开发区开展试验,累计试验10口井,封堵成功率为100%,取得良好效果,为油田外漏井治理提供了新的方向。

After many years of development,Daqing Oilfield has entered the middle and late stage of high water cut.Due to factors such as formation water corrosion,perforation,workover,abnormal pressure,casing deformation,casing damage and decline of cementing quality,the damage of production casing and channeling outside the casing are becoming more and more serious.The number of external leakage wells in shallow formation is increasing,which causes the hidden trouble of environmental protection.In order to solve this problem,the research of composite material plugging technology was carried out,which adopts the combination of mechanical and chemical plugging technologies to establish a process from network contruction,plugging to sealing.Many problems that may be encountered in the plugging operation have been solved,such as large amount of ineffective injection of plugging agent outside the casing,low concentration of mixed sand and sludge or water invasion in the annulus,too high consolidated cement plug column resulting in difficulty for pulling,waste of plugging agent,failure of plugging caused by consolidation strength,low operating efficiency,etc.In 2022,ten wells have been tested in Development Zone A,and the success rate of plugging is 100%,with good plugging results,which can provide a new direction for the treatment of casing external leakage wells in the oilfield.