Carbothermic reduction of siderite ore with high phosphorus content reinforced by sodium carbonate

A dressing metallurgy flowsheet, which consists of a sodium salt added reinforced reductive roasting-magnetic separation process, is proposed in this paper for the treatment of siderite ore with high phosphorous content. The sodium salt added reinforcement reductive roast process is accomplished by the addition of an appropriate amount of sodium carbonate, which reacts with SiO2 preventing its counter catalysis on FeO, thereby increasing the reducing reaction activity of FeO and further reinforcing the reduction of siderite. The phosphorus compounds were not reduced in the low temperature reduction process and remained as fluorapatite in the gangue phases. Ultrafine grinding-magnetic separation of magnetic minerals is an efficient way to obtain qualified iron concentrate. It is therefore believed that, with an emphasis on the effect of Na2CO3 and its dosage on the reduction of siderite, the technology proposed in this paper will be of benefit to the exploitation of similar refractory iron ore.