2016 Volume 102 Issue 7 Pages 375-379
The shaft furnace, which is a scrap melting furnace, plays an important part as an energy supplier in a steelworks, because the shaft furnace produces high calorie gas. The shaft furnace is required either to reduce coke rate or to increase exhaust gas calorie, corresponding to energy balance in the steelworks. Coke rate and exhaust gas calorie are determined by the coke gasification reactivity, so the control technique of the reactivity is very important. In this study, coke surface was coated by CaCO3, Fe2O3 and SiO2 to control the coke reactivity, and the gasification rates were measured at 1573-1773 K. As the results, the gasification rates were accelerated by CaCO3 and Fe2O3, and decelerated by SiO2. The acquired gasification rates applied to a one-dimensional mathematical model of the shaft furnace. The shaft furnace operations controlling the coke reactivity were simulated and the effects of the coke reactivity on coke rate and exhaust gas calorie were estimated.