Mechanism of improved magnetizing roasting of siderite–hematite iron ore using a synergistic CO–H 2 mixture

摘要: A fluidized-bed magnetizing roasting–magnetic separation process was selected to treat this type of material. Phase transformations and microstructural changes in the product resulting from roasting under different reducing gases (CO, H2, CO + H2) were clarified by vibrating sample magnetometry, X-ray diffraction, scanning electron microscopy, energy-dispersive spectroscopy. The results indicated that conversion ratio saturation magnetization samples roasted a mixed gas CO H2 higher than those produced or alone. This synergy combined had positive effect on process. mechanism kinetics improved siderite–hematite iron ore mixture synergistic CO–H2 system investigated isothermal conditions. apparent activation energies reactions oxides decreased 37.7 17.9 15.9 kJ/mol when atmosphere changed pure respectively. promoted hematite siderite magnetite, thereby improving