生物质直燃锅炉空气预热器腐蚀研究

Research on corrosion of air preheater of biomass fuel-directly fired boiler

对生物质直燃锅炉空气预热器换热管束的腐蚀原因进行了分析,认为空气预热器的腐蚀是低温露点酸腐蚀和碱金属沉积腐蚀共同作用的结果。将空气预热器换热管全部更换为搪瓷管后,空气预热器长期运行状况良好,热风温度远高于设计值,搪瓷管基本无腐蚀现象,综合使用寿命远超过原钢管,提高了机组运行的经济性。

The reasons of corrosion of the air preheater heat exchange tube bundle of a biomass fuel-directly fired boiler were analyzed,and it was determined that the air preheater's corrosion is caused by the low dew-point acid corrosion and the alkali metal deposit corrosion. The air preheater heat exchange tubes had been replaced by enamel tubes. Then the air preheater operates in good condition for a long term,the hot air temperature is much higher than design value,and the enamel tubes do not corrode basically. The comprehensive service live of the enamel tube is much longer than the service live of original steel tube.The economic efficiency of the unit was improved.