Gaseous Reduction of Hematite Ores containing High Phosphorus

Abstract

In the current study, the reduction behavior of high P iron ore pellets by CO-H2 gas mixtures was investigated. Total porosity, pore size distribution and surface area of the pellets were measured using the mercury pressure porosimeter. The reduction was carried out using the thermogravimetric analyses (TGA). The reduction rate increased with increase in temperature and was highest when 100%H2 was used. The reduction behavior could not be explained in terms of a single rate determination step. In the initial stage the reaction rate was controlled by chemical reaction and by diffusion in the later part of the reduction process. The calculated activation energy values range from 20.8 to 50.2 kJ/ mol. The elemental distribution in the reduced pellet of the ore was clarified using the EPMA.