洗涤塔腐蚀原因分析与预防

Analysis and Prevention of Corrosion in Washing Tower

某催化剂再生装置上的洗涤塔在停机检查时发现内部有严重的腐蚀。采用扫描电子显微镜、能谱仪、X射线衍射仪、体视显微镜等对腐蚀产物的宏观形貌、微观形貌及物相组成进行分析。结果表明,腐蚀产物疏松多层,局部有凹坑,腐蚀产物中含有Fe_2O_3,Fe_3O_4,Fe(OH)_3等化合物,且在腐蚀产物内表面发现Na元素,其腐蚀形貌与腐蚀产物组成与碱腐蚀一致。为减少此类腐蚀的产生,在生产中应加强残余氧、pH值、温度等因素的监控。

A washing tower on a catalyst regeneration unit was found to have serious internal corrosion during the shutdown inspection.The macroscopic and microscopic morphology,phase component composition of the corrosion products were analyzed with a Scanning Electron Microscopy,an energy spectrometer,an X-ray diffractometer and a stereoscopic microscope etc.The results show that the corrosion products are loose and multilayered with local pits,and composed of such chemical compounds as Fe2O,Fe3O4, Fe(OH)3 ,and Na element was found on the inner surface.The corrosion morphology and corrosion product composition are consistent with alkali corrosion.The monitoring of residual oxygen,Ph value and temperature should be strengthened in order to reduce the occurrence of such type of corrosion.