关键词: 含钛高炉渣, 选择性析出技术, 钙钛矿相含钛精矿, 硫酸酸解

Abstract:

Panzhihua Iron and Steel Co. releases 3 million tons of blast furnace slag containing 20% to 25% TiO₂ annually, resulting in a large amount of blast furnace slag occupying land, causing dust pollution and posing a threat. To solve the utilization problem of titanium containing blast furnace slag, this article adopted the “selective precipitation technology”, which involved adding insulation measures after the blast furnace slag was discharged to slowly cool the slag. The titanium component was enriched in the perovskite phase, and the grains grow. Further beneficiation and separation can obtain a concentrate of 35% to 50% TiO₂. In the paper, experimental study was conducted on sulfuric acid acidolysis of the perovskite concentrate. The research showed that the optimal conditions for acid acidolysis of the concentrate were: the mass ratio of ore to acid was 1 to 1.21, the reaction temperature was 180℃, the concentration of H₂SO₄ was 90%, the concentrate size was less than 76μm, and the reaction time was 4h. An acidolysis rate of 94.62% can be achieved under the optimal conditions. The acidolysis kinetics experiment indicated that in the initial stage (x=0—0.3), chemical reaction kinetics were the principal characteristic. In the intermediate stage (x=0.5—0.7), a mixture of chemical reactions and internal diffusion controlled the rate. In the later stage (x>0.7), the internal diffusion dominanted the rate.

Key words: titanium bearing blast furnace slag, selective precipitation technology, perovskite Ti-bearing concentrate, sulfuric acidolysis