某硫尾矿磁选精矿直接还原同步脱硫时的脱硫机理

Mechanism of Desulfurization of Direct Reduction Simultaneous Desulfurization of Magnetic Concentrate from a Sulfur Tailing

通过XRD分析和SEM分析,研究了内蒙某硫尾矿的高硫弱磁选精矿在直接还原同步脱硫过程中还原剂惠民褐煤和脱硫剂SH的脱硫作用机理。结果表明:惠民褐煤有一定的脱硫效果,其原因是因为惠民褐煤形成的高温还原气氛可使黄铁矿和磁黄铁矿生成气态单质硫、气态羰基硫、金属铁和非磁性的陨硫铁,气态硫的挥发及陨硫铁在焙烧产物磨矿—弱磁选时与金属铁的分离使硫得以去除。SH对脱硫起进一步的促进作用,其作用机理为SH在焙烧过程中与黄铁矿和磁黄铁矿生成金属铁和没有磁性的硫化钙,硫化钙通过焙烧产物磨矿—弱磁选与金属铁分离,使脱硫达到预期目标。

Using the XRD and SEM method to analyze desulfurization mechanism of Huimin lignite and desulfurizer SH for low intensity magnetic concentrate with high sulphur concent of sulfur tailings in Inner Mongolia by using direct re- duction roasting. The results show that the influence of reducing agent on the desulfurization has certain effect, the reason is that high temperature reduction atmosphere which formed by Huimin lignite can make pyrite and magnetic pyrite generating elemental sulfur and carbonyl sulfur in volatile gas state, metallic iron and troilite without magnetic, sulfur in volatile gas state and the grinding magnetic method to separate troilite and iron is the way to desulfurization. SH has promotion effect to the desulfurization. The mechanism is the desulfurizer SH and the pyrite and magnetic pyrite in direct reduction roasting process reacts iron and calcium sulfide without magnetic, through the grinding magnetic method to separate calcium sulfide and iron, so as to achieve the desulfurization target.