| Vanadium is a resource with high value, thus the recycling and comprehensiveutilization of the rich vanadium resource which is hosted in vanadium bearingtitano-magnetite contributes to the widespread application of vanadium to differentindustrial fields, and makes sense to the creation of higher economic benefit andcorporate profitability ultimately. In China, Pan Steel has the mature process called“BF-BOF” process to smelt vanadium bearing titano-magnetite, and it providestechnological base to the efficient recycling and comprehensive utilization of vanadiumresource hosted in Panxi Area’s vanadium bearing titano-magnetite.Recently, Pan Steel adopts measure of increasing the V-Ti ore ratio of blast furnacecharge to carry out blast furnace smelting. Because blast furnace smelting plays animportant role in the whole “BF-BOF” process, which provides high quality vanadiumbearing hot metal and matches the next vanadium recovering converter blowing process,the effect of these measures mentioned above on vanadium reduction in blast furnaceshould be considered. What’s more, whether the measures which are suitable forincreasing vanadium recovery percent in hot metal are also suitable for blast furnacenormal smelting is another question during the practical production process. So it needsthe thorough study of vanadium reduction characteristic during the process of vanadiumbearing titano-magnetite smelting in blast furnace.Based on the analysis above, this paper carries out the research of vanadiumreduction characteristic during the process of vanadium bearing titano-magnetitesmelting in blast furnace. By studying the behavior of vanadium in blast furnace and thereasonable measures to improve the reduction condition of vanadium oxides in blastfurnace, the reduction law of vanadium oxides in blast furnace is expected to beobtained and is used to guide the practical production. Some analyzing methods such asthermodynamic theory, kinetic theory, charge calculation theory, XRD and SEManalysis, laboratory simulation experiment has been adopted to support the research inthis paper and the following results have been achieved finally.①From the upper part to the lower part in blast furnace, vanadium with+3~+4chemical valence which was hosted in ore was gradually reduced into solid iron phase,and finally was reduced into hot metal mostly with0chemical valence, the othervanadium was reduced into slag and formed vanadium oxides(vanadium with+2~+3 chemical valence).②The result of charge calculation showed that cohesive zone and hearth were themajor reduction area of vanadium oxides with reduction degree of58%and70%respectively. The results of laboratory simulation experiment showed that: particle sizeof charge decreasing contributed to vanadium reduction in lumpy zone, temperatureincreasing contributed to vanadium reduction in blast furnace, V-Ti ore ratio increasingfrom66%to70%was beneficial to vanadium reduction in lumpy zone and thevanadium content in iron reached maximum (0.1299%) when V-Ti ore was68%incohesive zone, TiO2content in slag decreasing and binary basicity increasing were thefavorable conditions for vanadium reduction in hearth.③The relationship between vanadium reduction in blast furnace and blast furnacenormal production was studied. Results showed that:20mm sinter diameter wasfavorable for iron ore reduction and permeability in blast furnace,68%V-Ti ore ratiowas most favorable for vanadium reduction in cohesive zone and didn’t have a greateffect on pressure loss in blast furnace, oxygen enrichment operation wasn’t favorablefor vanadium reduction in hearth, unburned pulverized coal ratio increasing had littleeffect on vanadium reduction but affected slag viscosity remarkably, the favorableconditions for vanadium reduction, Ti(C,N) precipitation restraining and blast furnaceslag desulfurization at the same time were limited. |
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