Abstract: 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 reduction 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.

Key words: Low intensity magnetic concentrate from sulfur tailings, Direct reduction , simultaneous desulfurization, Reducing agent lignite, Desulfurization SH, Desulfurization mechanism