Estimation of indices of BF heat of titanium-magnetite concentrates with different titanium dioxide content

Abstract

Russia owns world largest reserves of titanium- magnetite and ilmenite- titanium- magnetite ores. Following the stepby-step inclusion into metallurgical processing of titanium- magnetite raw materials, the matter of maximum extraction of iron, vanadium and titanium becomes more and more actual. Kachkanar group of deposits of titanium- magnetite ores consists of two deposits: Gusevgoskoe and Sobstvenno-Kachkanar. At present JSC EVRAZ NTMK uses titanium- magnetite sinter and pellets, produced of Gusevgorskoe deposit ores. To make up the dropped out capacities and to keep the volume of mined ore at the level of 55 m t/year, it is planned to put into operation the reserved Sobstvenno-Kachkanar deposit. To process the titanium- magnetite ores of this deposit, their specific peculiarities should be taken into consideration. In particular, the increased TiO2content in iron ore concentrate up to 3.4% might require corrections of the BF technology. In this connection a study of metallurgical properties of lump iron ore raw materials with different titanium dioxide content was carried out. To clarify the pellets phase components a method of X-ray-phase analysis was used. The studies were done at CKP “Ural-M” equipment in the Institute of Metallurgy, Ural branch of Russian academy of Sciences. It was determined that pellets chemistry was represented by hematite (from 77 up to 89%), magnetite (from 2.84 up to 10.44%), complicated diopside (from 2 up to 10%), as well as in a small amount by quartz, hedenbergite, corundum, rutile, ferro-periclase, ilmenite, wollastonite, α-Fe, wustite. Results of viscosity calculation of obtained slags showed that it is within a range, typical for real BF slags viscosity. The obtained values of slag viscosity do not offer problems with slag regime of BF heat. It was shown, that increase of titanium dioxide content in pellets does not give rise to quality deterioration of iron ore raw materials preparation to BF heat as volume of introduced concentrate with increase TiO2content into the materials is increasing. Increase of hot strength and pellets temperature of beginning of softening, the pellets having increased titanium dioxide content, will positively affect main technical and economic indices of BF heat – coke rate and productivity, that was confirmed by BF indices calculation by application of balance logical and statistical model of BF process.