Study of Liquid Phase Formation during the Sintering of Chromite Pellets and its Effect on the Properties of Pellets

Abstract

For production of ferrochrome in submerged arc furnace (SAF), chromite ore is used in the form of lumps, briquettes and sintered pellets.The sintered pellets are preferred as a feed in SAF as it improves the furnace performance. During sintering of the green chromite pellets, bentonite reacts with silicate gangues in the chromite and forms the liquid phase which acts as a bin-der. The physical and metallurgical properties of the sintered pellets depend on the formation of liquid phase. The properties sintered pellets samples collected from the sintering plant were evaluated in the laboratory. The compressive strength of the samples varied significantly from 5 kg/pellet to 305 kg/pellet. The microstructure of the sintered pellets revealed that the porosity and form-ation of liquid phase affects the compressive strength of the pellets. In addition of this the oxidation of chromite grains during cooling of also influences the strength of the pellets and its metallurgical properties. The results of characterization studies are presented in this research work to relate the liquid phase formation and pellet properties for improved metallurgical applications.