氨法脱硫吸收塔内不锈钢腐蚀缺陷分析及处理

Analysis and Treatment of Stainless Steel Corrosion Defect in Ammonia Desulfurization Absorption Tower

解决田东电厂氨法脱硫吸收塔内316L不锈钢支撑梁腐蚀断裂问题。通过分析吸收塔内部各位置浆液中氯、氟离子浓度,发现浆液氯、氟离子浓度最高分别达到6 000 mg/L、19 200 mg/L,超过316L不锈钢允许使用范围。为此,将塔内所有316L不锈钢支撑梁换为表面涂玻璃鳞片防腐碳钢钢梁。经过近一年的运行,所换钢梁没有出现任何腐蚀现象,防腐效果良好。

In order to solve the corrosion cracking problem of 316 L stainless steel supporting beam of ammonia desulfurization absorption tower in Tiandong power plant, chlorine and fluoride ion concentrations of seriflux in different positions of the absorption tower are analyzed. It is found that the highest chlorine ion concentration and the highest fluoride ion concentration reach 6 000 mg/L and 19 200 mg/L respectively which beyond the allowed usage scope of 316L stainless steel. All 316L stainless steel supporting beams in the tower has been replaced by the anticorrosion carbon steel beams with surface coating of glass flake. After the operation nearly one year, all replaced steel beams has no corrosion phenomenon and thus has better anticorrosion effect.