Technical Analysis on Selective Separation and Enrichment of Ti-bearing Blast Furance Slag Based on Phase Diagrams

Technical and economical feasibilities on selective separation and enrichment of titanium containing BF slag were conducted. For the route of selective separation and enrichment with calcium oxide, perovskite separates out more sufficiently when slag composition is adjusted to the region CaSiO₃-Ca₃Si₂O₇-CaTiO₃. Gravity separation method is not suitable due to slight difference of phases' densities. Additionally, post-treatment of enrichment slag is very difficult and expensive. For the route of selective separation and enrichment with sodium oxide, it is very difficult for one-step route to produce quite pure enriched slag. Central Iron and Steel Research Institute invented two-step route, which could produce high quality enriched slag, utilize silicon resource and use sodium resource repeatedly. Therefore a high effective and green process comes into being for utilizing titanium slag comprehensively.