Study on volatilization of lead in melting-fuming process of iron vanadium slag

In this paper, the melting-fuming method, a type of pyrometallurgy, was used to recover the nonferrous metal lead(Pb) in iron vanadium slag, and the reaction conditions required for reducing metallic Pb during the roasting process were calculated by thermodynamic software. In addition, the effects of different process parameters during the recycling process on the lead Pb recovery ratio were investigated, the optimal conditions for comprehensive Pb recovery ultimately obtained, and the morphology, elemental composition and structure of the collected smoke dust characterized by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS)/energy spectrometry and X-ray diffraction (XRD). The results show that in the melting-fuming process, lead sulfide (PbS) in the iron vanadium slag first volatilizes into the form of soot when the reaction temperature is above 1 000 ℃. The Pb recovered in soot is mainly enriched in the form of lead oxide (PbO) and lead sulfide (PbS), in which lead oxide (PbO) is the oxidized product of lead single after volatilization, contained a quadrilateral shape. Pb recovery reaches 99.70% at the optimal reaction temperature of 1 242 ℃.