碳钢在高温发烟硫酸环境中的阳极保护研究及应用

摘要

The corrosion rate of anodized carbon-steel in fuming sulfuric condition which boasting of 100℃-300℃ temperature and 30% shell side was discussed. The experimental results show that at 300℃, its corro-sion rate can be decreased to 1.4mm/a from 35mm/a to benefit industrialized application of anodized sulfur trioxide evaporators; and the ideal critical passive current density for anodized carbon-steel approximates 1.5 A/m2 with 0. 3A/m2 or so for the maintaining passivity current density and about 2. 6V for the optimum protection potential relative to Hg/Hg2SO4 electrode.%研究了碳钢在100～300℃、30％的发烟硫酸中外加电流阳极保护条件下的腐蚀行为,其在300℃条件下腐蚀率由35.0mm/a降低至1.4mm/a,并实现了阳极保护三氧化硫蒸发器的工业化应用.从试验测试结果和设备现场使用的情况得出,在“碳钢-发烟硫酸”体系实施阳极保护的致钝电流密度约为1.5A/m2；维钝电流的密度约为0.3 A/m2；最佳保护电位相对于Hg/Hg2SO4(饱和K2SO4)电极约为2.6V.