Chemical and Physical Characteristics Affecting the Reduction Kinetics of Iron Oxide Pellets with Solid Carbon

Abstract

AbstractAn experimental study of chemical and physical parameters which control the reduction kinetics of oxide-carbon reactions is presented. It was found that both a finer particle size, and increased compaction pressure, resulting in a lower pellet porosity, increased the reaction rate. The temperature effect on the reaction rate clearly indicated chemical reaction control. It was found also that the rates of reduction are very sensitive to the chemical composition of the oxide. An acceleration of reduction rates at the wustite to iron stage was observed, increasing with the degree of reduction, confirming the catalytic effect of iron on the Bouduard reaction. Additions of trace amounts of Na2CO3 and K2CO3 also showed a pronounced increase in the reaction rate.The experimental observations have led to the interpretation that the reaction rate is a function of the degree of interparticle contact, the catalytic effect of different species and the evolution of the internal pellet morphology during reduction.