|About this Abstract
||2016 TMS Annual Meeting & Exhibition
||7th International Symposium on High Temperature Metallurgical Processing
||KK-9: Reduction Behavior of Magnetite Pellets by CO-CO2 Mixtures Using Direct Reduction Process
||Guihong Han, Tao Jiang, Yanfang Huang
|On-Site Speaker (Planned)
"Two-step process" is regarded as one sort of coal-based directed reduction process and employs oxidized pellets for reduction. In this paper, reduction behavior in the two step process was investigated respectively by means of weight-loss technique and visualizing physical changes of pellet under isothermal conditions. According to the dynamic calculation, the equation 1-(1-R) 1/3 = k•t is obeyed when reduction temperature is lower than 1000℃ and the reduction process appears to be controlled by chemical reaction with apparent activation energy of 72.27 kJ/mol. When the reduction temperature is higher than 1000℃, the equation of t/[1-(1-R)1/3] against [1+2(1-R)-3(1-R)2/3]/[1-(1-R)1/3] gives straight line, which demonstrates the reduction is mixed-controlled by chemical reaction and diffusion. The swelling index is firstly increased and then decreased with the increase of reduction time and reduction extent. The maximum swelling index is gradually increased with the increase of reduction temperature and CO content.
||Planned: A print-only volume