摘要：
A composite organic amine shutdown protection agent for power plant boiler was developed in this study.And the effects of its reaction temperature and concentration on the protective effects were investigated.Polarization curve method,wet and hot corrosion test,scanning electron microscopy,X-ray energy dispersive spectroscopy and X-ray diff action were used to study its protection mechanism.The results showed that,when the concentration of complex organic amine was 100 mg/L,pH was 10.0,and the temperature was kept at 300 °C for 4 h,the surface film forming of carbon steel and passivation protection effects were the best.Under the action of complex organic amine molecules,the closely linked ultrafme Fe3O4 spherical particles generated on the surface of the carbon steel specimens.At the same time,the carbon steel specimens physically adsorbed part of organic amine molecules to form a dense protective film.This protective film significantly reduced its corrosion current density and the wet and hot corrosion speed,and then obviously improved its corrosion resistance.This composite organic amine agent was applied to the protection of a 1 000 MW supercritical direct air-cooled boiler during the shutdown period.A complete and dense protective film was formed on the internal surface of power plant thermal equipment,and its breakdown time in deaerator by the acid copper sulfate was greater than 35 seconds,which exhibited great corrosion resistance.%研发了1种用于电站锅炉的复合有机胺停用保护剂,考察了反应温度和保护剂质量浓度对保护效果的影响,使用酸性硫酸铜滴定、极化曲线法、湿热腐蚀试验、扫描电子显微镜、X射线能谱和X射线衍射等技术对其保护机理进行研究.结果表明:当复合有机胺质量浓度为100 mg/L、温度300°C、pH=10.0,恒温4h时,碳钢试片表面成膜效果最佳,钝化保护效果最好;在复合有机胺分子作用下,碳钢试片表面生成紧密相连的超细Fe3O4球状颗粒,同时物理吸附部分有机胺分子,形成致密的保护膜,显著降低了碳钢试片的腐蚀电流密度和湿热腐蚀速度,提高其耐蚀性能.将复合有机胺应用于某电厂超临界1 000MW直接空冷机组的停用保护,其在热力设备内表面形成完整致密的保护膜,除氧器内耐酸性硫酸铜击穿时间大于35 s,表现出良好的耐蚀性能.
