Experimental Study on the Refining Desulfurization Slag Made from the Reduced Red Mud

Abstract

Red mud is unmanageable industrial waste produced from aluminum industry, which is difficult to be disposed and recycled with traditional method. In this paper, refining desulfurization slag was made from the reduced red mud, and the desulfurization abilities of the slag and the recovery rates of the metal Fe are studied. With thermodynamic simulation, orthogonal experiments, and verification experiment, it is found that binary basicity has significant effect on LS and ηs, while the effects of Al2O3 concentration in slag and the quantity of the reduced red mud are not obvious. The optimal combination with the best desulfurization ability can be derived as A3B2C2, which means the binary basicity of the optimal slag is 7, the concentration of Al2O3 is 30%, and the wt% of the residue is 15%, which means the reduced red mud quantity is 132.92 g. At the same time, the recovery rate of Fe element increases with the quantity of the reduced red mud, and the recovery rate of metal Fe in optimal combination slag is 87.84%. The separation of the metal Fe from the reduced red mud is satisfactory. The refining desulfurization slag manufacturing is a feasible method on the disposal and recycling of the red mud.