涪陵页岩气田水平井井筒积液诊断技术研究

Research on Diagnostic Technique of Wellbore Fluid in Horizontal Wells in Fuling Shale Gasfield

在页岩气田开发中气井由于受压裂液入地量高的影响,水平井在后期开采过程出现了不同程度的压裂液返排,部分气井已出现井底积液严重,甚至水淹停产的现象。针对涪陵页岩气井的生产特征,对涪陵页岩气田气井临界携液流量模型系数进行优化,结合气井生产动态特征判断和流压探液面法综合判断建立了井筒积液预警系统,涪陵页岩气田两百多口水平井井底积液诊断显示实际符合率在75%以上。

In the shale gasfield development, horizontal wells have different degrees of fracturing fluid backflow in the late production stage due to the influence of high volume of fracturing fluid injection, and some gas wells have serious bottom hole fluid accumulation or even water flooding and production stoppage. According to production characteristics of Fuling shale gas wells, model coefficient of critical fluid carrying rate in gas wells is optimized. An early warming system for wellbore fluid accumulation is established based on the characteristics of gas well production and fluid pressure sounding. The diagnosis of downhole effusion in more than 200 horizontal wells in Fuling Shale Gasfield shows that the actual coincidence rate is above 75%.