防止空气预热器露点腐蚀措施

MEASURES FOR PREVENTING DEW POINT CORROSION OF AIR PREHEATER

空气预热器常因发生露点腐蚀问题而影响其使用寿命。文章介绍了低温露点腐蚀机理和防止空气预热器露点腐蚀的改进方法。采用抗腐蚀材料和涂层技术可减缓腐蚀;烟气脱硫以及控制预热器冷端金属表面温度高于露点温度可防止发生腐蚀。某公司实测燃气火焰加热炉露点温度78℃,并以此作为控制预热器冷端温度依据。该公司应用“95+超净高效工业炉技术”和“复合相变换热器余热回收技术”两项新技术防止露点腐蚀,取得良好效果。

The service life of air preheaters is often affected by the occurrence of dew point corrosion. This paper introduces the mechanism of low temperature dew point corrosion and the improvement method for preventing the corrosion of air preheaters. The use of corrosion-resistant materials and coating technologies can slow down corrosion. Flue gas desulfurization and controlling the cold-end metal surface temperature of the preheaters above the dew point temperature can prevent corrosion. The measured dewpoint temperature of sulphuric acid in a gas flame heater is 78 ℃ which is used for pre-heater cold-end temperature control. The company applied two new technologies including "95+ high-efficiency industrial furnace technology" and "composite phase change heat transformer waste heat recovery technology" to prevent dew point corrosion, which achieved good results.