页岩气井滑溜水和返排液对N80钢和TP125V钢的腐蚀研究

Corrosion behavior of N80 and TP125V steel in slick water and flowback water from shale gas wells

目的研究不同液体对川渝地区页岩气井常用油管材质N80钢和套管材质TP125V钢的腐蚀行为。方法采用失重法和电化学法比较了现场返排液、现场滑溜水和实验室配制的滑溜水3种液体对N80钢和TP125V钢的腐蚀影响。结果在现场返排液环境中的腐蚀速率最大,实验室配制滑溜水中的腐蚀速率最小。结论N80钢和TP125V钢在现场返排液环境中,不仅整体腐蚀速率较在现场滑溜水或实验室配制的滑溜水中大,而且局部腐蚀也更加严重。

Objective The aim is to study the corrosion behavior of N80 tubing material and TP125V casing material commonly used in shale gas wells in Sichuan and Chongqing areas.Methods The corrosion effects of flowback water,on-site slick water and laboratory prepared slick water on N80 and TP125V steel were compared by weight-loss method and electrochemical method.Results The corrosion rate in the flowback water environment was the highest and in the laboratory prepared slick water was the lowest.Conclusions The overall corrosion rate of N80 and TP125V materials in the flowback water environment is not only higher than that in the on-site slick water or the laboratory prepared slick water,but also the pitting is more serious.