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PROCESS OF COKELESS WITHOUT WASTE TREATMENT OF DIRECT VANADIUM ... PROCESS OF COKELESS WITHOUT WASTE TREATMENT OF DIRECT VANADIUM ALLOWING MELTING

Lisienko, V.G., Droujinina, O.G., Morozova, V.A.., Ladigina, N.V., Yusfin Yu.S. and Parenkev A.E. Urals State Technical University, Mira str., 19, Ekaterinburg, Russia Moscow Stell and Alloys Institute, Leninskii av.,4, Moscow, Russia

\y/ Abstract: The development of new methods of steel production are now conducted with the purpose of energy consumption and harmful emissions reduction. The choice of technology and equipment in this case plays a cricinal role. It is well known that vanadium alloying steel has increased service properties. The known classical scheme of vanadium steel melting is very power-intensive, as includes such power- intensive processes as blast process and chemical processing of vanadium therewith sintering and by-product processes are accompanied by significant harmful emissions. In so doing the vanadium losses may run to 60%. In view of requests of environment protection and economical efficiency the new process of cokless without wastes processing of vanadium-bearing raw material with direct vanadium allowing of steel - LP-process is developed. Its purpose is the melting on the basis of vanadium-bearing titanomagnetite of vanadium allowing steel with increase of vanadium concentration in steel and diminution of vanadium losses without application coke and natural gas with use of any and -bearing wastes. LP-process consists of three aggregates and corresponding processes: process of liquid-phase reduction, process of vanadium-bearing pellets metallization in the shaft furnace, and process of alloying steel melting in the arc electric furnace. The obtained results have shown, that the LP-process is more energy saving on a comparison with other methods of vanadium allowing steel production.

1. INTRODUCTION In the well known classic schemes of vanadium steel melting the following plan is used: with vanadium cast melting - converter with steel and converter vanadium slag production - chemical processing of vanadium slag with pertaoxide of vanadium production - production with ferrovanadium making - melt of steel in the furnace with ferrovanadium use. However this process is very power-intensive, it includes such power-intensive processes as blast furnace process and chemical processing of vanadium slag, besides in present very long production chain 68-70% of vanadium is lost. In this process deficient expensive coke also is used, the production which one is attended by considerable harmful pollutant emission [1]. LP- process has following advantage. Melting of steel alloyed by vanadium, with increase of vanadium concentration in steel and decrease of vanadium losses without coke and gas application with usage any coals and carbon-bearing wastes. At vanadium-bearing titanomagnetite treatment additional steel alloying by , , , cobaltous, molybdenum and other components of allow, slag production with the content of a vanadium, titanium, aluminum, magnesium, radium and dispersed elements. Cost price of production reduction, environmental pollutant emission decrease [2- 4].

2. DESCRIPTION, KEY FEATURES AND BENEFITS OF PROCESS In known cokeless method of vanadium steel melting vanadium pellets arc produced with subsequent their use in the electric arc furnace with vanadium steel production. However in this process reduction gases obtained at conversion of expensive high-calorie fuel - natural gas arc used and in metal of electric are furnace commodity steel scrap and arc used, that reduces vanadium concentration and increases the content of cooper in steel [1].

54 Proceedings of 3rd BMC-2003-Ohnd, R. Macedonia PROCESS OF COKELESS WITHOUT WASTE TREATMENT OF DIRECT VANADIUM ...

In LP-process contrary to indicated process vanadium-bearing raw material, for example, vanadium pellets with the content of vanadium up 0.4-0.5%, proceed the reduction stage in metallization furnace, for example, in the shaft furnace, and as a reducer hot reduction gases (HRG) are used, obtained at gasification of carbon-bearing material, for example, energy or any carbon-bearing waste materials in liquid melting bath by process of liquid-phase reduction of iron and other elements (fig.l). Gasificator there with works in, so-called, mixing mode, i.e. with simultaneous reception HRG, and also metal half-product with the content of vanadium up to 0.5% and slag. In gasificator the carbon-bearing material, for example, energy coal or any waste products, and also vanadium-bearing ore raw materials, for example, Kachkanar vanadium-bearing titanomagnetite ore, vanadium-bearing pellets or briquette are loaded and is feeded. Vanadium-bearing half-product (cast iron), slag from gasificator and also metallized vanadium-bearing raw materials, for example, pellets are used as the charge of electric arc with reception of vanadium-bearing steel (content of vanadium up to 0.5-1.5%). The export gas of shaft furnace is used for combustion in fuel-oxygen burners of electric arc furnaces, that extraly allows to reduce the flow rate of natural gas usually applied in such fuel- oxygen burners. Therewith commodity steel scrap and cast iron in the charge of electric arc furnaces is not used that increases the content of vanadium and decreases the content of cooper in steel [2-4].

Ore Raw Material Export Gas Coal Ore Raw

Gasificator MLR HRG

Bubbling Slag Electric Arc Blow of Bath Furnace O2 *~ Slag Half-Product

Fig.l. Process of cokeless without waste treatment of vanadium-bearing ore raw material with direct vanadium allowing of steel LP-process melting (direct allowing) Thus, key features of LP-process: • Reduction of losses of vanadium and increase of its concentration in steel (by content of cooper reduction) by the same content of vanadium in initial charge; • Cokeless process without applying natural gas with use any carbon-bearing fuels, including energy coals and wastes; • At applying titanomagnetites - additional steel by many elements alloying and slag reception with the content of a series of alloying elements; • Low energy expenditure at the expense of applying of hot reduction gas, hot pellets, half-product and slag; • Reduction of the cost price of production and harmful environmental pollutant in an atmosphere for the score of cokeless process and without wastes technology.

Proceedings of 3"1 BMC-2003-Ohrid, R. Macedonia 55 PROCESS OF COKELESS WITHOUT WASTE TREATMENT OF DIRECT VANADIUM ...

3. STATUS AND BASIC PARAMETERS The technology is founded on results of experimental-industrial meltings held by the Moscow Institute of Steel and Alloys on the PLR-unit (Process of Liquid-Phase Reduction) of Lipetsk metallurgical Concern [5], and also on results of experience of vanadium-bearing pellets metallization in the shaft furnace of Beloretskiy metallurgical plant with subsequent their use in electric arc furnace held by the Ural Institute of Metals, VN1TMT (Scientific Resoilrcher Institute of Metallurgical Heat Technic), USTU (Urals State Technical University) [1] and other organizations. The basic parameters of treatment vanadium-bearing ore raw material in LP-process: • Vanadium-bearing ore raw (for example, titanomagnetite) up to 2.01 /1 of half-product; • Output of reduction gas - up to 2.2 m3 / kg of coal (in recalculation on energy coal); • Temperature of gas at outlet of gasificator - up to 1300 °C, at inlet of shaft furnace from 850 to 1050 °C;

• The content in reduction gas: CO - 50%, H2 - 30%; • The flow rate of hot reduction gas - 2000-2700 m3/t of pellets; • The flow rate of blow in gasificator with content of oxygen 52 - 64% up to 0.5 m3 / m3 of gas; • Degree of pellets metallization - 90 - 93%; • The content of vanadium in steel - 0.5 -1.5%. The basic prediction productivities of experimental-industrial LP-unit: • Gasificator with the area of hearth 20 m2; • Outlet of gas from gasificator - up to 60000 mVh; • Outlet of metallized pellets - up to 30 t/h; • Volume of shaft furance - 160 m3; • Melting of vanadium steel by 40% melallized pellets in charge - 43 t/h; • Electrical arc furance capacity - 50 t.

References 1. Rovnushkin V.A., Bokovikov B.A., Bratchikov S.G. et al. Without Coke Treatment of Titanomanetite Ores. Moscow: Metallurgiya, 1998. P. 247 (in Russian). 2. Lisienko, V.G., Romenetz V.A. Parenkev A.E. et al. Method of Cokeless Treatment of Vanadium- Bearing Raw Material With Vanadium Allowing Steel Waste Production. Patent of Invention of R.F. M 2167944. Byul. N° 15, 27.05.2001. 3. Lisienko, V.G., Schelokov Ya.M., Rosin S.E. and Droujinina, O.G. Algorithms and Comparative Energy Capacity of Steel Melting Processes. Steel, 2000, j<9.9. pp. 19-24 (in Russian). 4. Lisienko, V.G., Droujinina, O.G., Parenkev A.E. and Ladigina, N.V. Estimation of LP-process on Material Heat Balances . Izvestiya Vuzov. Chornaya Metallurgy, 2001, N°ll. pp. 9-14 (in Russian). 5. Romenetz V.A. Process of Liquid-Phase Restoration of Iron: Development and Realization. Steel, 1990, mS, pp. 20-27 (in Russian).

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