Modelling of chemical reactions in metallurgical processes

Abstract

Iron-ore reduction has attracted much interest in the last three decades since it can be considered as a core process in steel industry. The iron-ore is reduced to iron with the use of blast furnace and fluidized bed technologies. To investigate the harsh conditions inside fluidized bed reactors, computational tools can be utilized. One such tool is the CFD-DEM method, in which the gas phase reactions and governing equations are calculated in the Eulerian (CFD) side, whereas the particle reactions and equation of motion are calculated in the Lagrangian (DEM) side. In this work, this method has been extended to cover the most common types of representation models for the reactions of solids submerged in fluids. These models are the Shrinking Particle Model (SPM) and the Unreacted Shrinking Core Model (USCM). With the use of the SPM, the implemented communication framework between the CFD and DEM sides have been verified by running some preliminary cases and comparing the species mass balances. In the modelling of iron-oxide reduction the SPM is insufficient to represent the different reaction steps, therefore a three-layered USCM is utilized. The implemented USCM is validated by running some preliminary cases.