A Methodology to Quantify the Physico-chemical Phenomena during Induration of a Single Magnetite Pellet

Induration of magnetite pellet involves three important phenomena, namely oxidation, sintering and associate heat transfer; these phenomena are interdependent on determining the final quality of the pellet. In order to study the sintering a novel optical dilatometric method was used. These studies were performed separately for magnetite and completely oxidized magnetite. Further, the sintering phenomena was modeled taking cues from powder metallurgy literature. In order to study the oxidation kinetics, TGA analysis were conducted both at powder and pellet scales at sufficiently low enough temperatures so that sintering effects are minimized. Interesting results that has not been reported earlier have been observed and these results could be explained using available gas-solid reactions models both at powder and pellet scales. Once the sintering and oxidation models were validated independently, they were integrated along with heat transfer model to realize a comprehensive induration model. These efforts have resulted in a Single Magnetite Pellet Induration Model (SPIM) which in principle can be used for optimizing raw material mix as well as the process parameters at the reactor scale.