Role of Flocculation and Dispersion in Pelletization of Iron Ore

Traditional modeling of iron ore pellet strength utilizes micromechanical models such as Rumpf’s equation, which correlate attractive forces and pellet properties into an average expected pellet strength. These models combine with repulsive forces within pellets to predict that pellet strength decreases with the introduction of these forces. However, naïvely applying Rumpf’s equation readily leads to incorrect predictions about the resulting behavior. Pellets created with strong repulsive forces arising from dispersion conditions are observed to be significantly stronger overall than pellets formed in the absence of dispersants. A new model is required to understand and predict the effects of these additives within the iron ore pelletization process. This model can be developed by expanding on the coordination number term within Rumpf’s equation utilizing information from the repulsive forces of dispersants. In particular, pellet strength roughly doubles under dispersion, which is most strongly promoted by anionic polymers