Effect of reductant sodium bentonite content and reaction temperature in sponge iron production from composite pellets

Abstract

In recent years, composite pellet production with added reductant has been developed instead of traditional iron production. Composite pellets produced by the addition of appropriate proportions of reductant produce sponge iron in the reductant melting process at high temperatures. The elements created in the structure by pellet production directly affect the quality of the product obtained by determining the chemical composition and the appropriate reaction temperature. In this study, sponge iron ore concentrate (scale) and reductant (coke coal dust and sodium bentonite) were mixed at certain proportions to produce composite pellet samples; the effects of addition rate of the reductant material of sodium bentonite (1 wt%–4 wt%) and variation in reaction temperature (900–1200 °C) on the metallization and compressive strength properties of the produced composite pellet samples were investigated. The analysis results show that the highest compressive strength is obtained from pellet samples produced with 3% sodium bentonite at 1100 °C. Additionally, SEM-EDS analysis results of the samples show that the morphologic structure has much lower porosity rates compared to samples produced under the other conditions which makes the samples denser and increases the metallization properties.

Keywords

solid waste / reduction / iron oxides / pellets / sponge iron

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