摘要
研究了P110SS钢在含低硫化氢油气井下腐蚀规律及特征。通过高温高压反应釜模拟超深井的腐蚀工况,对P110SS钢在不同温度、H_(2)S、CO_(2)分压条件下进行浸泡实验,通过腐蚀失重计算其腐蚀速率,辅以SEM、EDS和XRD等手段对腐蚀产物的形貌和成分进行表征。结果表明,H_(2)S、CO_(2)分压增大均会导致P110SS的腐蚀速率增大;然而温度升高却降低其腐蚀速率。分析腐蚀产物可见,H_(2)S、CO_(2)浓度和温度的变化均会导致腐蚀产物成分和结构发生转变。说明在高温高压条件下,H_(2)S腐蚀起主导作用,Fe7S8腐蚀产物对基体的保护作用较差,腐蚀速率高;低H_(2)S分压下,CO_(2)腐蚀起主导作用,腐蚀速率的大小取决于腐蚀产物膜的致密性;相比于CO_(2),温度对腐蚀速率的影响更显著。
The corrosion condition of ultra-deep oil-and gas-wells is simulated via a high-temperature and high-pressure reaction kettle that can adjust the temperature,H_(2)S-and CO_(2)-partial pressure of the artificial formation waters.The corrosion characteristics of P110SS steel in the artificial formation water by varying temperature,and H_(2)S-and CO_(2)-partial pressure,was assessed by means of immersion test,SEM,EDS and XRD.The results show that the corrosion rate of P110SS increased with the increase of H_(2)S and CO_(2)partial pressure,but decreased with the increase of temperature.By analyzing the corrosion products,it is found that the change of H_(2)S-,CO_(2)-partial pressure and temperature will lead to the change of composition and structure of corrosion products.This shows that under the condition of high temperature and high pressure,the corrosion of H_(2)S is dominant,the corrosion product of Fe7S8 has poor protectiveness and thus the steel presents high corrosion rate,and the corrosion of CO_(2)is dominant under the condition of low H_(2)S partial pressure,the corrosion rate depends on the compactness of the corrosion product film.However,the effect of temperature on the corrosion rate is more significant than that of CO_(2).
作者
幸雪松
范白涛
朱新宇
张俊莹
陈长风
XING Xuesong;FAN Baitao;ZHU Xinyu;ZHANG Junying;CHEN Changfeng(CNOOC Research Institute Co.,Ltd.,Beijing 100028,China;School of New Energy and Materials,China University of Petroleum,Beijing 102249,China)
出处
《中国腐蚀与防护学报》
CAS
CSCD
北大核心
2023年第3期611-618,共8页
Journal of Chinese Society For Corrosion and Protection