Suspension magnetization roasting on waste ferromanganese ore: A semi-industrial test for efficient recycling of value minerals

Abstract As a waste ferromanganese ore resource, unavailable due to conventional technology and thus hoarded in mass quantity, in which it functions as an invaluable recycling value. In the study, an efficient semi-industrial test for recycling manganese and iron was investigated by suspension magnetization roasting, and with the results demonstrating that iron concentrate with an average iron grade of 66.60% and an average iron recovery of 93.93%, manganese concentrate with an average manganese grade 46.22% and an average manganese recovery 87.29% could be obtained under conditions of roasting temperature 500 °C, reducing agent concentration 45%, reducing agent dosage 12.0 m3/h and the equipment operating continuously and stably for 35 h. Through the suspension magnetization roasting-magnetic separation technology, the weak magnetic hematite, pyrolusite and bixbyite were selectively converted into magnetite and manganosite respectively, and then the magnetite and manganosite were extracted in the magnetic concentrate and magnetic tailings individually. Suspension magnetization roasting semi-industrial system exhibited stable and efficient performances for the recycling and utilization of ferromanganese ore.