某海底管道内腐蚀原因分析及防护

为了确保海底管道安全、有效运行，基于腐蚀相关标准以及腐蚀控制经验，采用XRD分析和Oddo-Tomson饱和指数预测等方法，对某油田海底管道的天然气组分、清管垢样、内检测结果、加注缓蚀剂以及CO2腐蚀机理、结垢预测结果进行了综合分析和内腐蚀评估。结果显示，该海管中存在以FeCO3为主的腐蚀产物，管道中水质具有CaCO3和FeCO3结垢倾向。研究表明，该管道发生了CO2腐蚀，缓蚀剂浓度可能无法满足低度腐蚀的防护要求，建议增加缓蚀剂浓度或更换其他型号缓蚀剂。

Cause Analysis and Protection of Internal Corrosion in Subsea Pipeline

In order to ensure the safe and effective operation of subsea pipelines, based on relevant corrosion standards and corrosion control experience, XRD analysis and Oddo-Tomson saturation index prediction methods were used to comprehensively analyze and evaluate the natural gas composition, pigging and scaling samples, internal inspection results, injection of corrosion inhibitor, CO₂ corrosion mechanism and scaling prediction results of subsea pipeline in an oilfield. The results show that there are mainly FeCO₃ corrosion products in the subsea pipeline, and the water quality in the pipeline has the tendency of CaCO₃ and FeCO₃ scaling. he research shows that CO₂ corrosion is found in pipeline, and the concentration of corrosion inhibitor may not meet the protection requirements for low corrosion. It is recommended to increase the concentration of corrosion inhibitor or replace another type of inhibitor.