Effect of Suspension Magnetization Roasting Temperature on the Properties of Roasted Products of Chongqing Jielong Iron Mine

Siderite is an important iron ore resource in China. Suspension magnetization roasting is an effective method to deal with complex refractory iron ores. In this paper, a small laboratory suspension magnetization roasting device is used to carry out the research on the optimization of suspension magnetization roasting process and the effect of roasting temperature on the performance of magnetized roasted products for Chongqing Jielong iron mine. The results show that under the conditions of roasting temperature of 500℃, roasting time of 3 min and CO dosage of 0.2 L/min, the iron concentrate grade of 56.31% and recovery rate of 92.05% were obtained. XRD analysis shows that in the range of 450~550℃, most hematite can be transformed into magnetite by reduction roasting for 3 min. Increasing the temperature is conducive to the more thorough reduction of hematite, and the reduction temperature has little effect on the magnetism of roasted products. After reduction roasting, the specific surface area of the pre oxidized sample decreases, and the pore structure collapses and is filled, resulting in the increase of pore size. The change of pore structure may have a certain impact on the subsequent grinding and magnetic separation. The research results have certain significance for understanding the law of suspension magnetization roasting.