煤气化装置关键设备腐蚀预测与选材

Corrosion Predictction and Material Selection of Key Equipments of Coal Gasification Unit

煤气化装置的混合气流中含有水蒸气、游离水及其混合物等多种形态的H2O以及CO2、H2S、SO2等多种酸性气体,存在多种腐蚀风险。通过分析煤气化装置关键设备大型化、结构复杂化、材质多样化、原料煤质多样化等特点,总结了炼油厂静设备腐蚀损伤机理,指出了腐蚀预测、腐蚀分析和腐蚀评定对煤气化装置安全稳定运行的重要性。介绍了双组分游离水相图分析方法,通过实例示范了该方法在某石化装置管线腐蚀预测中的应用。从熟悉煤气化装置物料的基本特点、设备选材的基本要求、几种典型煤气化腐蚀工况下选材原则及积累煤化工装置设备选材经验几个方面探讨了煤气化设备选材的考虑要素和方法。

The mixed air flow of coal gasification device contains various forms of H2O such as vapour , free water and its mixture, as well as multiple acidic gases included CO2, H2S, SO2, etc., which have a lot of corrosion risks. The characteristcs of key static equipments of coal gasification was analyzed firstly. The equipment trend are upsizing, structural complexity, materials diversification and quality of raw coal diversification. The corrosion damage mechanism of static equipment of oil refinery is analyzed and summarized, and the importance of corrosion prediction, corrosion analysis and corrosion evaluation for safe and stable operation of coal gasification is showd clearly. The analysis method of two-component free water phase diagram is introduced and its application in pipeline corrosion prediction of a petrochemical plant is demonstrated by an example.The elements and methods of material selection of coal gasification equipment were discussed from the aspects of familiar with the basic characteristics of coal gasification materials, basic requirements of equipment selection, selection principles of several typical coal gasification corrosion conditions and accumulation of experience in material selection of coal gasification equipment.