Development of predictive model for fly-ash erosion phenomena in coal-burning boilers

The effects of ash particle physical properties and transport dynamics on the erosive wear of three different grades of low alloy steel, using three different power-station ash types, were determined in this study through experimental investigation. The study used a Taguchi fractional-factorial L27 DOE. The experimental data were used to derive a model for the prediction of erosion rates. The model incorporates the properties of the ash particles and the target metal surface, as well as the characteristics of ash particle motion in the form of the impingement velocity and the impingement angle. Given the availability of large number of experimental data, it became possible to predict the relationship between erosion loss and the factors influencing the rate of room-temperature erosion. Fly-ash particulate size and concentration, moisture and titania content, impact velocity and angle, duration of impact, and alloy surface roughness were determined to be first-order effects.