A general model for moving-bed reactors with multiple chemical reactions part I: Model formulation

•A general model is developed for moving-bed reactors with multiple reactions.•The grain model is adopted and modified as the kinetics model.•The proposed model covers the modified grain model.•The model predictions are obtained for an industrial moving-bed for hematite pellets reduction.•The model well simulates the experimental data with an average 1.2% error.

A general model is developed for moving-bed reactors where multiple non-catalytic gas–solid reactions and multiple gas-phase reactions take place. The grain model is adopted and modified as the kinetics model for multiple non-catalytic gas–solid reactions case. The proposed model covers the modified grain model and provides the local degree knowledge of the origin solid reactant along with the intermediate solids within the porous pellets. The heat transfer by convection, conduction and radiation in the gas bulk and the radial temperature distribution of the pellet are considered. The model predictions for solid conversion, gas temperature, and gas concentrations are obtained for an industrial moving-bed reactor for Fe2O3 pellets reduction. This proposed model well simulates the experimental data with an average 1.2% error.