| Panzhihua and Xichang area is the world-famous Vanadium and Titanium Capital for the enrichment of V-Ti magnetite resources. The Vanadium and Ttitanium resources hosted in the polymetallic paragentic mineral deposits in the form of V-Ti magnetite. About 50% titanium in the V-Ti magnetite enter into the concentrate iron ore during the Mineral Separation, after the blast-furnace slag is smelted, which nearly all enter into the Ti-bearing blast furnace slag containing 20～26%TiO2. At present, a large number of slags have been piled up resulting in environmental pollution and resources waste. Although decades of researches and efforts, the utilization of the slags has not been given. Therefore, it is an urgent practical problem to study the extraction and utilization of valuable components from the blast-furnace slags.In order to extract the titanium components from the blast furnace slag effectively, the chemical composition, phase composition and microstructure of air-cooled and water-quenched blast furnace slags are analyzed and investigated. The results show that the two kinds of slags have similar chemical compositions. However, there are big differences in the phase compositions and microstructures between the two kinds of slags, which should be caused by the different cooling ways after the slags are ejected from the slag hole. To prove this deduction, the phase transformation of water-quenched blast furnace slag by heat treatment process was investigated. XRD analysis shows that the phase compositions are the same between the air-cooled blast furnace slag and the water-quenched one which is heated at 1200℃for 4h, and the crystallization order is about that perovskite, spinel, Ti-rich diopside and Titatic pyroxene. The Thermodynamic calculation indicates that the various components in blast furnace slag can react with hydrochloric acid spontaneously.By the experimental research, the three-step process route of acid-alkali-acid leaching reaction is adopted to deal with the air-cooled blast furnace slag. The pretreated experiment on the Ti-bearing blast furnace slag cooled in air by the Hydrochloric acid reveals that under the conditions of reaction time keeps for 4 hours, reaction temperature keeps at 100℃, the Hydrochloric acid concentration is 6mol/L, acid/slag mass ratio keeps at 1, a higher leaching rate of magnesium, aluminum, calcium and a lower leaching rate of titanium of blast furnace slag can be obtained as well as the preparatory selective impurity is achieved.In the above acid leaching residue, most of magnesium, alumina and calcium are removed off, and the titanium components are relatively enriched. In order to obtain Ti-rich slag, the residue then is treated by alkali leaching process to remove silicon, and the process parameters is optimized. In the process of removing silicon from the residue by alkali, where the most of magnesium, alumina and calcium are removed off, and the titanium components are relatively enriched. It is found that when the reaction temperature keeps at 100℃, reaction time keeps for 2h, alkali/slag mass ratio keeps at 0.5, the obtained Ti-enriched slag mainly occurs in the form of perovskite, which contains about 80% TiO2. In the meanwhile, the silicon components in the filtrate have been recovered by hydrochloric acid treatment process. To study the further enrichment of titanium components, the Ti-enriched slag is purified by the hydrochloric acid . The result shows that part of the diopside and spinel in slag can be removed off in the acid leaching process, at the same time, the perovskite is also participating the reaction.
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