Research On The Direct Reduction Technology Of V-Ti Magnetite Concentrate

Vanadium-titanium magnetite is grandidierite consisted of iron, vanadium, titanium and other elements, which have a high utility value. But it is so difficult to carry out the utilization of vanadium-titanium magnetite by using conventional metallurgical methods. Hence, in order to achieve the comprehensive utilization of resources, it is necessary to find out new utilization technology of vanadium-titanium magnetite.With vanadium-titanium magnetite concentrate and anthracite as the main raw materials of direct reduction, with an addition of additives, the direct reduction technology of vanadium-titanium magnetite in solid state was studied, and finally use the grinding and magnetic separation technology to achieve effective separation of iron and titanium. The direct reduction technology of vanadium-titanium magnetite in solid state has solved the issues in the traditional process, in which the temperature is so high while the metallization rate is low. Magnetic separation technology has solved the problem of effective separation of iron and titanium. The whole process has the characteristics of low energy consumption, short process, high recycling rates of titanium and other elements, and opened up a feasible and effective way for the comprehensive utilization of vanadium-titanium magnetite.The main contents are as follows:(1) The effects of reduction temperature, reduction time, the amount of anthracite and additives on the metallization rate of the reduction were studied, and finally determined the optimal conditions. When the reduction temperature is 1250?, reduction time is 120min, the addition of anthracite and sodium sulfate is 13wt% and 2.0wt% respectively, the metallization rate of the reduction can be more than 95%.(2) The effects of reduction temperature and the amount of reductant on the phase composition, the characteristic and distribution of elements were studied, and finally achieved a better separation of iron and titanium under the optimal conditions.(3) The effects of reduction temperature and time on the grain growth of iron were studied, determined the grain growth kinetic equation of iron,which is D4=kt and belongs to the control of volume diffusion and growth mechanism, and calculated the apparent activation energy of grain growth in the range of 1050?1200?, which is 113.74kJ/mol.(4) The influence of the magnetic field strength and grind size on the separation of iron and titanium were studied, and the optimum conditions for grinding and magnetic separation was determined. Under 130mT magnetic field strength and 48?m of grind size of experimental conditions, the recovery rate of iron and titanium was respectively 93%and 72%, got over 50% TiO2 grade titanium concentrates and total iron content of iron ore concentrate was 70%, achieving a good separation of iron and titanium components, and finally solved the issues of the recovery of iron and titanium.