Erosion-corrosion occurrence

Basically there are two approaches to predicting the occurrence of erosion corrosion. Practical or experience based methods typified by Keller s approach for carbon steels in wet steam. Keller developed an equation that related the erosion corrosion rate as a function of temperature, steam quality, velocity and geometric factor. In recent years this approach has... 

Erosion corrosion may be considered at the design stage when a wider range of options is available to prevent its occurrence than if it occurs after the item of plant has been built. Various options and examples for these two situations are summarised in Table 1.32. 

The flame imprinted characteristics of pulverized coal ash relevant to boiler slagging, corrosion and erosion have been discussed previously (1,2). Silicate minerals constitute between 60 and 90 per cent of ash in most coals and boiler deposits are largely made up from the silicious impurity constituents. This work sets out first to examine the mode of occurrence of the silicate mineral species in coal followed by a characterization assessment of the flame vitrified and sodium enriched silicate ash particles. The ash sintering studies are limited to investigations of the role of sodium in initiating and sustaining the bond forming reactions to the formation of boiler deposits. 

I i n i ng An inner surface applied to process equipment to prevent or reduce the occurrence of corrosion, erosion, or the damaging effects of temperature. The surface may bea coating ora shield such as glass, lead, or in the case of furnaces, heat-resistant brick. 

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