SAF2205双相不锈钢换热器的化学清洗

某大型石化公司常减压蒸馏装置减压塔顶系统水冷器管束用SAF2205双相不锈钢制作,使用已经2a。使用过程中发现管束壳程减压塔顶油气系统出现堵塞现象,已经影响装置的平稳运行。在没有可借鉴经验的情况下,对SAF2205双相不锈钢管束壳程沉积的大量结垢进行了化学清洗。由于SAF2205双相不锈钢的特殊性,为防止硫化亚铁自燃以及发生连多硫酸腐蚀,制定了复配以络合剂和螯合剂为主的清洗技术路线,实践证明达到了预期的效果,换热器使用效率大为改观。

Chemical Cleaning of SAF2205 Duplex Steel Heat Exchangers

The tubes of overhead water cooler of vacuum tower of a large atmospheric - vacuum distillation unit were fabricated with SAF2205 duplex stainless steel tubes. After 2 years＇operation, the shell side of the cooler in which the overhead oil vapor flows experienced blocking, which affected the normal operation of the unit. To solve this problem, the shell side of the SAF2205 duplex stainless steel tubes was chemically cleaned to remove the large amount of fouling. In cleaning, the cleaning process with complexing agent and chelator was applied based upon the properties of SAF2205 duplex stainless steel to prevent autoignition of iron monosulfide and corrosion of polythionic acid. Heat transfer efficiency has been greatly improved and expected results have achieved.