Iron Recovery from Nickel Slag by Aluminum Dross: Viscosity Evolution in Different Periods

Nickel slag can be recycled as one of the excellent secondary sources due to valuable iron resource. Slag viscosity during iron recovery from nickel slag by aluminum dross was studied from 1773 to 1873 K, and the viscosity evolution in different periods was systemically discussed. Experimental results showed that slag viscosity increased suddenly after "FeO"/("FeO" + Al2O3) ratio lower than 0.53, signifying the transition of dominant role from "FeO" to Al2O3. Structure investigation by Raman spectra showed the center of curves transferred to higher shift, which indicated the formation of many more complicated structural units during the reduction process. Furthermore, the increasing units ratio (Q(2) + Q(3))/(Q(0) + Q(1)) in [SiO4]-tetrahedra showed a good agreement with the variation of apparent activation energy.