分别采用活性胺和氨水作为碱化剂模拟直接空冷机组空冷岛环境,采用电化学试验、浸泡试验和形貌观察等研究了20号钢在不同碱化剂环境中的耐蚀性。结果表明:活性胺作为碱化剂,20号钢在汽相、液相环境中都具有更好的耐蚀性。实际应用结果表明,直接空冷机组采用活性胺作为机组停运保养碱化剂,在机组检修后再次启动的过程中,水汽系统的铁含量少、颗粒物粒径小且机组启动历时短。采用活性胺作为碱化剂进行停机保养的防护效果优于氨水。

Active amine and ammonia water were used as alkalizing agent to simulate the air cooling island environment of the direct air cooler group. Electrochemical tests, immersion tests, and morphology observation were used to study the corrosion resistance of No. 20 steel in different alkalizing agent environments. The results showed that when active amine as an alkalizing agent, No.20 steel had revelatively high corrosion resistance in both vapor and liquid phase environments. The practical application results showed that when active amine was used as the alkalizing agent for unit shutdown and maintenance in direct air cooling units, the water vapor system had low iron content, small particle size, and short start-up time during the process of restarting the unit after maintenance. The protective effect of using active amines was better than that of ammonia water as alkalizing agents for shutdown maintenance.