Mathematical Modeling of Fluidized Bed Magnetizing Roasting of Iron Ore Fines

Abstract

The fluidized bed magnetizing roasting of low-grade iron ore fines is employed as a beneficiation technique in iron-making and steel-making industries. In the present work, the unreacted shrinking core reaction kinetic model is coupled with the two-fluid and kinetic theory of granular flow gas–solid flow model to simulate magnetizing roasting of hematite to magnetite in iron ore fines using a fluidized bed reactor. The model is validated with published experimental findings. Thereafter, the influence of different process parameters such as gas temperature, composition, velocity, and particle size on the reduction fraction and rate along with (Formula presented.) mass fraction and emission is studied. The reduction rate increases with gas temperature and (Formula presented.) mass fraction while it decreases with particle size. The (Formula presented.) emission increases with gas temperature, particle size, and (Formula presented.) mass fraction. However, the influence of gas velocity on these parameters is not significant. The reduction rate and time vary from 0.0010 to 0.0067 s?1 and 65 to 553 s, respectively, at a reduction fraction of 0.5. The (Formula presented.) mass fraction and emission range from 0.80 to 0.92 and from 0.63 to 4.14 g kg?1 ore, respectively. © 2024 Wiley-VCH GmbH.