Sustainable Mining and Metallurgy

Converter vanadium slag is a kind of multi-metal mineral resource containing vanadium, titanium and chromium, and its available value is very high. In this paper, the principle, process flow and process characteristics of traditional vanadium extraction process and new process of vanadium slag were reviewed, and the development direction of comprehensive utilization of vanadium slag was prospected. The traditional vanadium extraction process from vanadium slag are sodium roasting-water leaching process and calcification roasting-acid leaching process. Subsequently, salt-free roasting-acid leaching process, magnesium salt roasting-acid leaching process, manganese salt roasting-acid leaching process and other improved processes were successively developed. The characteristics of these processes are as follows: vanadium slag is first subjected to high temperature oxidation roasting, and then vanadium is extracted by water leaching or acid leaching. The characteristics of new processes such as sub-molten salt method and sulfuric acid oxygen pressure leaching method are that vanadium slag does not need oxidation roasting, and vanadium is directly extracted by acid leaching or alkali leaching under a certain oxygen pressure. By constructing a reasonable and efficient new physical and chemical system of acid leaching or alkali leaching metallurgy, the direct extraction of vanadium, titanium and chromium from vanadium slag by wet leaching process and the comprehensive recovery of valuable elements such as iron and manganese will be the development trend of comprehensive utilization of vanadium slag.