Fundamental Research On Oxidation Phase Transformation Reaction Characteristics And Separation Mechanism Of Vanadium Titanium Magnetite Concentrate

The composition of vanadium titanomagnetite concentrate（VTC）is complex,and the titanium content is high and mostly exists in the titanomagnetite in the form of lattice substitution.It is difficult to effectively reduce the titanium content by the traditional beneficiation process.In this study,the idea of oxidative phase transition of VTC and Fe-Ti separation was put forward.Based on the process mineralogy of VTC,it focused on the thermodynamics of oxidative phase transition of VTC,the influencing factors of oxidative roasting experiments,and roasting.The key issues such as the influencing factors of product magnetic separation and flotation separation have carried out systematic basic research work.Process mineralogy studies show that the Fe and TiO₂ contents in the VTC samples are 54.70%and 13.23%,respectively,and the main constituent minerals are titanomagnetite.96.04%of iron is present in titanomagnetite,and 92.99%of titanium is present in titanomagnetite.Thermodynamic calculations show that the VTC can be decomposed into titania and magnetite at 400℃.Ca B₂O₄ and Ca SO₄ are bad reactants of VTC;Ca（OH）₂ and CaCO₃ are good reactants of VTC.The oxidative roasting experiment of VTC shows that the additive is calcium carbonate,the proportion is 20%,the roasting temperature is800℃,and the roasting time is 5 h is the best condition for the reaction with VTC.Titanium can be efficiently converted into perovskites.The separation experiment was carried out on the roasting products of VTC.The grade of iron obtained under the optimal magnetic separation conditions was 57.0 wt.%,the recovery rate was 69.8%,and the grade of TiO₂ was 3.2 wt.%.The grade of iron obtained under the optimal flotation experiment was 57.5 wt.%,the recovery rate was 71.2%,and the grade of TiO₂ was 2.9 wt.%.The research results in this paper enrich the theoretical system of the oxidative phase transition and Fe-Ti separation of VTC,and also have good reference significance for the efficient utilization of other complex ores.There are 41 figures,16 tables and 115 references in this dissertation.