Abstract:

Carbon capture, utilization and storage (CCUS) technology plays a critical role in achieving carbon neutrality goals and mitigating climate change. The captured CO₂ containing H₂O will cause serious corrosion damage to the pipeline system. This study focused on the potential corrosion-prone component of the transportation system-welded joints and investigated the corrosion behavior and mechanisms of X65 pipeline steel welded joints in water-rich and CO₂-rich environments. The results revealed that in CO₂-rich environments, the uniform corrosion rates in different regions of the welded joints were relatively low, likely due to the formation of FeCO₃ product films. In contrast, in water-rich environments, the uniform corrosion rates increased significantly, with no notable differences between different regions. The heat-affected zone exhibited pronounced pitting corrosion with deeper pits and higher surface roughness.

Key words: CCUS, welded joint, film, supercritical carbon dioxide, corrosion

摘要：

碳捕集、利用与封存（CCUS）技术对于实现国家双碳目标和减缓气候变化具有至关重要的作用。捕集得到的含H₂O的CO₂会对管输体系造成严重的腐蚀危害。本研究从输送体系可能的耐腐蚀薄弱环节焊接接头入手，研究X65管线钢焊接接头在富H₂O相以及富CO₂环境中，各区域的腐蚀行为与机理。结果表明，在富CO₂相中，焊接接头各区域的均匀腐蚀速率均较低，这可能与生成了FeCO₃产物膜有关；而在富H₂O相中，焊接接头各区域均匀腐蚀速率显著升高，各区域均匀腐蚀差异并不明显，在热影响区出现了更为明显的点蚀深坑，且表面粗糙度较高。

关键词: CCUS, 焊接接头, 膜, 超临界二氧化碳, 腐蚀