常减压蒸馏装置常顶换热器腐蚀原因分析及预防

Causes of Corrosion of Atmospheric - vacuum Distillation Unit Overhead Heat Exchangers and Prevention

中国石化股份有限公司天津分公司常减压蒸馏(Ⅱ)套装置的常顶换热器管束,自2003年8月份以来多次发生腐蚀泄漏。经调查,由于电脱盐装置的脱盐合格率仅为14.5％,因此塔顶馏分油中的H2S,HCl和管板焊缝部位焊接应力共同作用,导致了管板焊缝发生了应力腐蚀。加强"一脱三注"管理,管内涂覆涂料以及选用09Cr2A1MoRe或RT360材质的管束可预防腐蚀泄漏的发生。

The tubes of atmospheric overhead heat exchangers in No. 2 atmospheric - vacuum distillation unit in Tianjin Petrochemical Company have experienced a number of corrosion leakages since August 2003. The investigation has found out that the corrosion leakages are caused by H2 S and HCl in the overhead fractions because of off - spec desalted crudes and wedding stress at the welds of tube sheet which lead to the stress corrosion of the tube sheet welds. Strengthening 'One Removal and Three Injections' management, application of coating and selection of 09Cr2AlMoRe or RT360 material can prevent the corrosion leakage from occurring.