Experimental evaluation of the usage of residues for sintermaking

Abstract

The shifts in quality of global reserves of iron ore, as well as the progressive advances in environmental legislations, are tendencies that have motivated researches on the usage of iron and carbon-bearing residues in the production of sinter for blast furnace ironmaking. These residues, however, are commonly limited in use due to their physical (particle size distribution) and chemical (heavy metals, alkali and zinc contents) properties as compared to sinter feed. In that sense, it is necessary to verify the impact of these materials on sinter quality and on sintering process parameters. In order to assess the recycling potential of residues via sintermaking, mixtures with increasing proportions (4.5–50%) of iron and steelmaking residues were prepared and tested in controlled laboratory conditions representing those of the sintering machine. The effect of residues on sinter mineral phases and chemical quality was evaluated and showed few differences in sinter quality for a mixture resulting from recycling 100% of a plant’s residue generation (4.5% of the mix). The greatest impact was an increased presence of wustite in the produced sinter, beyond 25% of residues in the mixture. The results indicated that there are opportunities, in the industry, for increasing the recycling of residues via sintermaking. Keywords: Sintermaking, Residues, Iron Ore, Recycling