Separation of manganese and iron for low-grade ferromanganese ore via fluidization magnetization roasting and magnetic separation technology

Abstract

As a potential solid waste resource, low-grade ferromanganese ore has not been fully utilized or recycled. In this study, fluidization magnetization roasting and magnetic separation technology were used to recycle low-grade ferromanganese ore. X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive spectrometry (EDS), sample vibrating magnetometer (VSM), X-ray photoelectron spectroscopy (XPS), transmission electron microscope (TEM) were used to systematically detect the process mechanism. The results show under the optimized conditions, high-quality products of iron concentrate with iron grade of 69.05% at iron recovery of 95.94%, and a manganese concentrate with manganese grade of 53.30% at manganese recovery of 90.41% were obtained. The fluidization magnetization roasting technology can make the weak magnetic hematite in raw ore transform to the strong magnetic magnetite, while it makes the pyrolusite and braunite transform to manganosite. The newly formed mineral lattice had clear stripes and remarkable magnetization properties. After magnetic separation, magnetite and manganosite were individually separated at individual concentrates, which efficiently transforms and utilises this low-grade ferromanganese ore without any residue using this process.