生物质混煤燃烧过程中硫氯成分协同腐蚀作用机理探析

生物质混煤燃烧过程的腐蚀问题主要由燃料中硫氯成分造成,涉及气、液、固多相作用。按腐蚀形式从气相和积灰两个方面对协同腐蚀进行探讨:气相中硫氯组分共同对受热面发生侵蚀,二者还会发生反应生成硫酸盐附着于金属壁面,使高温氯腐蚀现象在一定程度上得到抑制,但当积灰中碱金属盐,硫酸盐和其他腐蚀产物共存时会产生局部液相加速腐蚀反应,同时促进气相腐蚀进行。协同腐蚀机理主要基于活性氧化作用,硫酸盐化反应,低温共熔体形成等。

Study on Synergy Corrosion Mechanism of Sulfur-Chlorine during Biomass and Coal Co-firing

The corrosion problem during biomass and coal co-firing is mainly caused by sulfur and chlorine component, involving gas, liquid and solid multiphase effect. According to the corrosion form, the synergy corrosion of sulfur and chlorine is investigated from gas and deposit aspects: in the gas phase, sulfur and chlorine component will jointly corrode heating surface, however reactions between them will generate sulphates, which may suppress the high-temperature chlorine corrosion to a certain extent. While alkali salts, sulfates and other corrosion products coexist in the deposit on heating surface, liquid phase will be produced locally and accelerate corrosion reactions, gas phase corrosion will be promoted simultaneously. The synergistic mechanism is mainly based on active oxidation, sulfation and low temperature eutectic formation.