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The gasification rate in CO 2 of the coke analogue containing calcium oxide was studied using analogues doped with alumina (corundum), calcium aluminates (CA6, CA, C3A) and lime minerals. The coke analogue is a laboratory material with simplified carbon structure that has a mineral component with a particle size, size distribution and mineral dispersion that can be controlled. The main focus of this study was to quantitatively assess the effect of calcium in the mineral on the analogue’s reactivity. The analogues were reacted with CO 2 isothermally in the temperature range of 1173–1623 K. It was found that the reaction rate increased with increasing CaO activity/number of moles of Ca in the mineral. The relative reaction rates (from lowest to highest) of the analogues doped were alumina, CA6, CA, C3A and lime. The relative apparent activation energies of the gasification from lowest to highest was lime, C3A, CA, CA6 and alumina. [ABSTRACT FROM AUTHOR]

Coke is a key reagent in the iron blast furnace process. To enhance its performance in the blast furnace, better understanding of the kinetics of coke’s reactions in the blast furnace is necessary. This study introduces and evaluates a new approach for the coke kinetic studies, through the use of a coke analogue. The analogue has been developed as a laboratory test material to minimise uncertainty associated with the complexity and inherent heterogeneity of industrial coke when used in coke gasification studies. Kinetic studies of the reaction of coke analogue with CO 2 were conducted using thermogravimetric analysis at temperatures between 1173 and 1623 K. It was found that the analogue displayed similar reaction behaviour to industrial coke and chars; the gasification rate of the coke analogue was found to increase with increasing temperature. Two temperature zones corresponding to different kinetic control regimes, chemical reaction controlled and mixed controlled, have been identified, similar to those found for industrial coke. This has been interpreted as indicating that the coke analogue is a suitable tool for the study of coke gasification kinetics. [ABSTRACT FROM AUTHOR]