摘要
针对黄磷尾气燃气锅炉省煤器的腐蚀问题,模拟316L不锈钢在多聚磷酸环境中的腐蚀行为,然后对省煤器中被腐蚀的316L不锈钢的表面形貌、腐蚀产物组成和结构进行分析.研究结果表明,316L不锈钢的腐蚀速率受温度和多聚磷酸浓度的影响,腐蚀速率随温度升高和多聚磷酸浓度降低而增大;腐蚀产物主要由P、Cr、Fe、Ca、Ni和Si等元素组成,同时含有少量的Al、S、Cl、Mn、Cu和Mo,存在MnO2、Fe(PO3)3、CrO3、Fe3(PO4)2、CaSO4、SiO2、Cr5O12、MoO2和Ca(PO3)2等化合物;腐蚀机制涉及金属基材中元素的溶出和晶格缺陷的形成,导致点蚀坑的产生,同时腐蚀溶液中的P和O元素与金属元素结合形成腐蚀产物.
Abstract
In response to the corrosion problem of the economizer in yellow phosphorus tail gas boiler,the corrosion behavior of 316L stainless steel in a polyphosphoric acid environment is simulated,the surface morphology of 316L stainless steel,composition and structure of corrosion product after corrosion are analyzed.The results indicate that the corrosion rate of 316L stainless steel is influenced by temperature and polyphosphoric acid concentration,with an increase of corrosion rate under high temperature and low concentration conditions.The corrosion products mainly consist of elements such as P,Cr,Fe,Ca,Ni and Si,along with trace amounts of Al,S,Cl,Mn,Cu and Mo,contain MnO2,Fe(PO3)3,CrO3,Fe3(PO4)2,CaSO4,SiO2,Cr5O12,MoO2 and Ca(PO3)2.The corrosion mechanism involves the dissolution of elements from the metal substrate,formation of lattice defects,resulting in pitting corrosion,and the combination of P and O elements from the corrosion solution with metal elements to form corrosion products.
基金项目
云南省科技重大专项(202202AG050001)
NETL
NSTL
万方数据