【摘要】 为分析低温甲醇洗装置换热器的腐蚀泄漏原因，利用扫描电镜（SEM）、能谱仪（EDS）和X射线衍射仪（XRD），分别测定了失效管束的微观结构、元素分布和物相组成；利用X射线荧光光谱仪（XRF）测定封头处污泥的元素含量。此外，通过腐蚀模拟试验表征了富硫甲醇对换热管材质的腐蚀特性。结果表明，失效换热管存在多处腐蚀穿孔，最大直径为2.5 mm，腐蚀穿孔壁面近似垂直，且在其周围区域未发现异常减薄；腐蚀产物主要为硫铁化合物，同时在污泥中检测出大量含硫成分；高温显著加剧换热管材料腐蚀，80℃时腐蚀速率达到0.138 mm/a；在换热器运行过程中，富硫甲醇中H₂S部分解吸形成了H₂S-H₂O电化学腐蚀环境，导致换热管出现均匀减薄，而污泥附着引发的垢下腐蚀是换热管腐蚀穿孔的主要原因。采取添加缓蚀阻垢剂、升级换热器材质等措施，可降低换热器的腐蚀风险，延长设备的运行周期。研究结果可为低温甲醇洗装置的腐蚀防控及换热器选型提供理论依据和工程参考。更多还原

【Abstract】 To analyze the corrosion and leakage causes in heat exchangers of low-temperature methanol washing unit,scanning electron microscopy（SEM）,energy-dispersive spectroscopy（EDS） and X-ray diffraction（XRD） were used to examine the microstructure,elemental distribution,and phase composition of the failed tubes. X-ray fluorescence（XRF） was employed to determine the elemental content of sludge in the header. Additionally,corrosion simulation experiments were conducted to characterize the corrosive effects of sulfur-rich methanol on the heat exchanger material.Results showed that multiple corrosion perforations（maximum diameter:2.5 mm） existed in the failed tubes,with perforation walls nearly perpendicular and no abnormal thinning observed in surrounding areas. The corrosion products primarily consisted of iron-sulfur compounds,and significant sulfur-containing components were detected in the sludge.High temperature markedly accelerated material corrosion,with a corrosion rate reaching 0.138 mm/a at 80 ℃.During operation,partial desorption of H₂S from sulfur-rich methanol formed an H₂S-H₂O electrochemical corrosion environment,leading to uniform thinning of the tubes.Under-deposit corrosion caused by sludge adhesion was identified as the primary cause of perforation.Measures such as adding corrosion and scale inhibitors and upgrading the heat exchanger material can mitigate corrosion risks and extend equipment service life.The research can provide theoretical basis and engineering reference for corrosion prevention and control of low-temperature methanol washing unit and heat exchanger selection.更多还原