页岩气井井筒腐蚀规律与防护措施

为了明确页岩气井井筒的腐蚀规律,对现场取得数据进行灰色关联分析,确定CO2分压、硫酸盐还原菌含量的关联度大于0.7,为影响腐蚀的主控因素。通过动态腐蚀评价试验测定温度、压力、CO2分压和硫酸盐还原菌含量对N80钢和P110钢腐蚀速率的影响。通过腐蚀失重法开展了缓蚀剂的评价及优选试验,结果表明:缓蚀剂2在加注量为200m/L时,对N80钢和P110钢有较好的缓蚀效果,且此时经济效益最大化。

Corrosion Law and Protection Measures of Shale Gas Well Wellbores

In order to clarify the corrosion rules of shale gas well wellbores,agray correlation analysis on the data obtained on site was performed and it was determined that the correlations of CO2 partial pressure and content of sulfate-reducing bacteria were greater than 0.7,and thus these two factors were main controlling factors affecting corrosion.The effects of temperature,pressure,CO2 partial pressure,and sulfate reducing bacteria content on the corrosion rate of N80 and P110 samples were determined by dynamic corrosion evaluation test.Evaluation and optimization tests of corrosion inhibitors were carried out by corrosion weightlessness method.The results show that the corrosion inhibitor 2 had a good corrosion inhibition effect on N80 steel and P110 steel when the injection amount was 200 m/L,and the economic benefits were maximized at this time.