Kinetic Investigation of Self-reducing Briquettes of Electric Arc Furnace Dust Produced with Charcoals

The objective of this study was to characterize electric arc furnace dust (EAFD) and investigate the kinetic parameters involved in the reduction of self-reducing briquettes produced with EAFD and different charcoals. The characterization was carried out by chemical analysis, x-ray diffraction, size analysis, and scanning electron microscopy. The self-reducing briquettes were made with 50 wt.% carbon excess. Thermogravimetric tests were carried out for temperatures in the 700-1100 degrees C range. The product was characterized using x-ray diffraction analysis. The results showed that EAFD was composed mainly of iron (zinc ferrite, Fe3O4, and metallic iron) and zinc (zinc ferrite and zincite). The thermogravimetric test results indicated that the reduction of self-reducing briquettes occurred in two steps. The first step was controlled by the phase boundary, with E-a in the 137.6-200.3 kJ/mol range. The second step was controlled by diffusion, with E-a in the 360.5-378.8 kJ/mol range.