Research On The Strenthening Of Solid-Phase Reduction And Magnetic Seperation Of High Chromium Vanadium Titanomagenetite

There are 3.6 billion tons of high chromium vanadium titanomagenetite in Panxi areas, the ore is rich in associated vanadium, titanium, chromium resources, so it has a very high utilization value. High chromium vanadium-titanium magnetite mineral composition is complex, so comprehensive utilization is difficult, and currently study on high chromium vanadium-titanium magnetite utilization abroad is very little, and industrial production is basically empty. Therefore, how to rational and efficient use of high-chromium vanadium-titanium magnetite, how to improve iron, vanadium, titanium, chromium utilization level, is currently a major issue to be solved.In this paper, the solid-phase reduction behavior and magnetic separation process intensification of high chromium vanadium titanomagenetite concentrate from Panzhihua was systemically studied by thermodynamic principles, chemical analysis, phase analysis and SEM analysis. On this basis, the process parameters for the comprehensive utilization of vanadium-titanium magnetite with new technology are optimized and also provide a theoretical basis. The conclusions show as following:(1) By studying the influence of C/O, reduction temperature, reduction time on the metallization of reduction products, the optimum parameters of the experiment are obtained as follows:C/O is 1.1, the reduction temperature is 1350?, reduction time is 30min. Under the conditions, the metallization rate of reduction product reached 81.62%.(2) With Na2CO3, CaF2, boric acid and borax added at 1200? and heating 30min, the reduction effect enhance obviously, instead of adding NaHCO3 inhibit reduction. CaF2 for the promotion of solid-phase reduction is the most significant, By comparing with no additives(69.19%), the metallization rate increased by 17.65%. Three kinds of composite additives (CaF2+borax, CaF2+boric acid, borax+boric acid) have a promoting effect on solid-phase reduction, but the promotion effect is weaker than a single additive.(3) Cooling way has enormous influence on the metallization rate of solid-phase reduction, the metallization rate of reduction product is improved when changing furnace cooling way to water quenching way, the metallization rate reached up to 96.79%. Water quenching is an effective method of desulfurization and dephosphorization, the best effect of desulfurization is 1250?, reducing 39.58% of S content, the best effect of desulfurization is 1200?, reduce 45.28% of P content in the product.(4) When reduction product with CaF2 was cooled by using water quenching under the condition of 1200? and heating 30min, the metallization rate reached 93.08%. It achieved the goal of a high metallization rate at low temperature.(5) Magnetic field intensity has a great influence on iron recovery rate, at 1150? and 1200?, the iron recovery rate increases at first and then decreases with the increase of magnetic field intensity, at 1250?,1300? and 1350?, the iron recovery rate showed rising trend with the increase of magnetic field intensity, considering the effect of magnetic separation and the consumption of energy, the optimum magnetic field strength is 160kA/m. The iron recovery rate is only less than 90% t 1150?, it reached more than 90% at other temperature conditions. Magnetic field intensity has a little effect on magnetic items.(6) Distribution of V, Ti, Cr in magnetic product changed with different reduction temperature. With temperature increased, the proportion of Ti in the magnetic materials reduces, the proportion of Cr in the magnetic materials increases, the proportion of V change a little.(7) When using water quenching, the magnetic phase is mainly ferrous materials, non-magnetic material is mainly gangue phase. The non-magnetic materials are mainly composed of V2O3, TiO2, MgAl2O4, CaTiO3, Fe0.5Mg0.5TiO5 and CaMgSi2O6.(8) By comparing magnetic items and iron recovery rate, the magnetic separation effect of adding CaF2 water quenching is better than adding CaF2 furnace cooling.Solid-phase reduction and magnetic separation process of high chromium vanadium titanomagenetite get rid of depending on carbon coke, small pollution, short flow, small investment, low production cost, is advantageous to the comprehensive utilization of the valuable elements, etc. So it is suitable for processing high chromium vanadium titanium magnetite resource in our country and has prospects foe promotion and use.