Reduction Kinetics of Composite Steel Slag-Coke Pellets

Generation of slag during steel making is a process consequence but it produces in high volume and management of such wastes is a primary environmental concern and a challenge also for the steel making industries. Steel slag is rich in mineralogy, such as iron oxides, calcium oxide, silicon oxide, magnesium oxide, manganese oxide, and aluminum oxide etc. Out of these, the major minerals in the steel slag are iron and calcium oxides. The iron content in such slag is 25–35%, which varies with steel production processes. Iron recovered from the slag can be used for secondary steel industry replacing a handsome amount of scrap. In this experiment, the kinetics has been investigated during the solid reduction of iron oxide from the slag are studied at different coke-to-slag ratios, different reduction temperatures for different reduction times. Here, the coke-to-slag ratio was taken as 0.5, 1, and 1.5 for reduction temperature 1000, 1100, and 1200 ℃ with 15, 45, and 120-min reduction time. The kinetic and reduction parameters like activation energy and pre-exponential factor for solid stage reduction of EAF slag are calculated with the help of Coats-Redfern methods.