富满油田易塌井环空气液混注反循环清砂技术应用

Application of Air-liquid Mixed Injection Reverse Circulation Sand Cleaning Technology in the Annulus of Prone-to-collapse Wells in Fuman Oilfield

富满油田属碳酸盐岩储层,裸眼完井占比高达97.7%,受前期储层改造及后期生产过程中生产压差变化、地层应力释放及注水替油等多因素影响,储层岩性疏松,产层垮塌砂埋时有发生,由于井超深(6500~7500 m)、井漏失返严重等客观因素限制,缺乏配套高效的重建生产通道裸眼清砂作业技术。因此,针对塔里木超低压井特殊复杂井井况,对传统反循环清砂技术进行了改进,将单循环介质的传统反循环清砂技术优化为多循环介质的“环空气液混注反循环清砂”新技术,并将优化后的技术探索性地应用于现场,成功解决了清砂效率低下等问题,大幅提升了油井利用率与采油效率,为突破超深碳酸盐岩易垮塌井重建生产通道的瓶颈技术提供了新思路,对国内外同类油田的井下作业具有重要参考和借鉴意义。

Fuman Oilfield belongs to carbonate reservoir and the proportion of open hole completion is as high as 97.7%.Due to the influence of many factors such as the change of production pressure difference,the release of formation stress and the replacement of oil by water injection in the early reservoir reconstruction and later production process,the reservoir lithology is loose,and the collapse and sand burial of the production layer occur from time to time.Due to the limitation of objective factors such as ultra-deep wells(6500~7500 m)and serious lost circulation,there is a lack of matching and efficient open-hole sand cleaning technology for reconstructing production channels.Therefore,in view of the special and complex well conditions of ultra-low pressure wells in Tarim,the traditional reverse circulation sand cleaning technology is improved,and the traditional reverse circulation sand cleaning technology of single circulating medium is optimized as a new technology of"mixed injection of circulating air liquid reverse circulation sand cleaning"with multiple circulating medium.The optimized technology is applied to the field exploratoryly,which successfully solves the problems of low sand cleaning efficiency,greatly improves the utilization rate of oil wells and oil recovery efficiency,and provides a new idea for breaking through the bottleneck technology of reconstructing production channels in ultra-deep carbonate rock collapse wells.It has important reference and significance for the downhole operation of similar oilfields at home and abroad.