水媒管式烟气换热器材料耐腐蚀性评价

Evaluation on Material Anti-corrosion Performance of Water Medium Heat Pipe Gas Gas Heater

水媒管式烟气换热器在工作中面临酸露的腐蚀,换热管材料需具备耐腐蚀性。模拟了水媒管式烟气换热器的腐蚀环境,采用自行设计的浸泡试验方法对8种候选材料的耐腐蚀性进行了比较,并采用扫描电镜对材料腐蚀后的表面形貌进行了研究。结果表明,ND钢在高浓度硫酸中的耐腐蚀性优于碳钢;不锈钢254SMO在各种浓度硫酸溶液中的腐蚀速率均较低;聚四氟乙烯塑料(PTFE)具有优异的耐腐蚀性。

Water medium heat pipe gas gas heater （WGGH）heat exchanger faces acid dew corrosion in oper鄄ation. Therefore,the material of heat exchange tube must be corrosion resistant. The corrosive environment ofWGGH is simulated and corrosion resistances of eight material candidates are compared by using self-de-signed soak test. Besides,surface topography of the material after corrosion is investigated by means of scan-ning electron microscopy. The result shows that anti-corrosion performance of ND steel is superior to that ofcarbon steel in high-concentration sulphuric acid;the corrosion rates of stainless steel 254SMO are all lowerin sulphuric acid solutions with different concentrations; polytetrafluoroethylene （PTFE）plastic is of favorableanticorrosion performance.