Application of Pellet Sintering in Manganese Ore Fines and Its Consolidation Behavior

The high solid fuel consumption has been a persistent problem for Steel production mills during the sintering process of manganese ore fines. This manuscript adopts the method of pellet-sintering to process manganese ore fines, and investigates the optimization of the sintering parameters for manganese ore fines, as well as its agglomeration mechanism. The sintering pot tests shown that the pellet-sintering required about 3.5% coke breeze dosage significantly lower than the traditional sintering (about 5%–10%), while the sintering indices can be achieved a yield of 71.12%, a tumble index of 62.48%, a solid fuel consumption of 55.87 kg/t, and a productivity of 1.29 t·h−1·m−2 under the condition of pellet size is 8–12 mm. XRD and SEM-EDS analyses indicated that the major mineral phases of sinter products included hausmannite (Mn3O4), ferrotephroite [(Fe,Mn)2SiO4], Fe–Mn oxides (FexMn3-xO4), bustamite [(Mn,Fe,Ca)·5(Si5O15)], rich-Mn bearing silicate melts and a small quantity of free quartz (SiO2). Optical microstructure and SEM images showed that hausmannite and Fe–Mn oxides are in blocky, with crystal-to-crystal bridging connections. ferrotephroite is rodlike, with a small amount appearing skeletal. The well-developed crystals are intertwined and closely interconnected, greatly enhancing the quality of the sinter product.