再生塔顶冷凝系统二氧化碳腐蚀行为研究

Study on Carbon Dioxide Corrosion Behaviors of Regeneration Overhead Condensing System

在脱硫再生塔顶冷凝系统的连接管线中、冷却器的换热管线表面因CO_2的存在发生均匀腐蚀或局部腐蚀。针对此现状,以管线为研究对象,采用极化测试试验法,对常用三种管线钢20#钢,Q345R钢,321不锈钢进行腐蚀试验研究,得出40℃时Q345R的耐蚀性最好,50、60℃时,321不锈钢的耐蚀性效果最明显;50℃的Q345R腐蚀速率最大,321不锈钢腐蚀速率的波动范围最大,20#钢腐蚀速率波动相对平缓。

In the desulfurization regeneration overhead condensing system connecting line,surface cooler tubes line occurs uniform corrosion or localized corrosion due to the presence of CO_2. For this situation,in the pipeline for the study,polarization test was used for the corrosion of 20# steel,Q345 R steel,321 stainless steels. The result showed that in 40 ℃,Q345 R showed the best corrosion resistance. In 50 ~ 60 ℃,the corrosion resistance of stainless steel 321 had most obvious effect. Q345 R reached the maximum corrosion rate in 50 ℃,321 stainless steel had the largest corrosion rate,20# steel corrosion had relatively flat rate fluctuation.