Application of nonisothermal kinetic techniques on the reduction of three commercial iron ore agglomerates

摘要

The mechanism of reduction of iron ore agglomerates by both isothermal and nonisothermal TG studies was investigated, and the work was complemented with the structural characterization of the total and partially reacted samples. Three different commercial hematite pellets were studied. The mechanisms of reduction were obtained under isothermal conditions, resulting in a fitting to chemical reaction models. Nonisothermal reduction was carried out using a TGA system (CAHN TG-171) from 600 to 1, 000 deg. C maintaining a lineal heating rate of 4, 7 and 10 deg. C/min, and the reducing atmospheres used were H_2(100/100) and H_2-CO(95:5).