The pretreatment of non-ferrous metallurgical waste slag and its research progress in the preparation of glass-ceramics

Due to containing abundant FeOx, Si and trace heavy metals (Pb, As, Cr, Cd, etc.), the disposal of non-ferrous metallurgical waste slag (NMWS), such as copper slag, lead slag, zinc slag and nickel slag, has attracted more and more attention. When the NMWS is applied as raw material for preparing glass-ceramics, the heavy metals in NMWS could be well solidified in glass-ceramics. However, the FeOx or Si content in NMWS would easily affect the melting process of NMWS and increase energy consumption. This greatly limits the large-scale application of NMWS on glass-ceramics. Based on the review of glass-ceramics prepared by NMWS, this work focuses on the pretreatment technology of pig iron and ferrosilicon alloy prepared by NMWS. In addition, the influence of FeOx and elemental Si components on the glass-ceramics process, and the solidification mechanism of glass-ceramics on heavy metals are discussed in detail. It is found that not only NMWS is suitable for the production of high value-added products such as iron, ferrosilicon alloys and glass-ceramics in a cascade utilization mode, but also that these recycled or prepared products are beneficial to save process energy consumption and reduce carbon emissions. This work pays special attention to the cascade utilization, process energy consumption, and carbon emissions of NMWS to maximize the conversion of NMWS into high-value products through energy-saving and emission-reduction channels.