Effect of Basicity on the Reduction Behavior of Iron Ore Pellets

Physicochemical properties of the iron ore pellets depend on the iron oxide concentrate, gangue content and the amount of fluxes added. The objective of this present work is to study the reducibility as well as the softening–melting behavior of the iron ore bearing fines (mainly containing hematite) pellet with lime to silica ratio (C/S) varying from 0.9 to 2.4 in the temperature range of 1100–\(1400 \,^{{\circ }}\hbox {C}\). Reduction test results show that the highest degree of reduction and degree of metallization of about 95.1 and 94.3%, respectively, are achieved for pellets having C/S ratio 1.6 reduced at \(1400\,^{{\circ }}\hbox {C}\) for 60 min. Further increase in C/S ratio resulted in lowering the reduction rates due to the formation of calcium ferrite phases as confirmed from X-ray diffractogram and photomicrographs. However, softening–melting characteristics study of slag (C/S above 1.6) revealed that the slag of C/S ratio 2.0 can be considered as primary slag.