RU2307178C2 - Manganese-containing raw material agglomeration method - Google Patents

Abstract

FIELD: ferrous metallurgy, namely manganese- containing raw material agglomeration processes.

SUBSTANCE: method comprises steps of metering, mixing, palletizing and sintering under pressure charge including lime stone, hard fuel, manganese-containing raw material and low-silicon iron-containing material and being in the form of slime of steel melting production or scale; performing palletizing by successively applying on lime stone particles with fraction size 5 - 0 mm at first low-silicon iron containing material and then mixture of manganese containing materials and hard fuel. Invention provides increased by 5 -6 times efficiency of aggregate, increased mechanical strength of product due to lowered by 26.7% consumption of hard fuel.

EFFECT: possibility for creating conditions for producing highly basic manganese containing raw material with increased mechanical strength, improved efficiency of method and aggregate for performing the same.

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Description

The invention relates to ferrous metallurgy, in particular to a technology for the agglomeration of manganese ores with a particle size of less than 6 mm, blast furnace dust and slags of manganese ferroalloy production.

The decrease in material and energy consumption in the production of manganese ferroalloys is closely related to the improvement of schemes for the preparation and sintering of manganese raw materials. The most famous mastered industrial method of agglomerating domestic manganese ore raw materials, which has been developed in the last decade, is agglomeration. (see Safonov B.M., Murakhovsky V.V. // Development of the production of manganese ferroalloys in electric furnaces // Steel, 1983. No. 5. - 5-7 pp .; Nezhurin V.I., Karmanov E.S., Kucher I.G. // Study of the gas dynamics of the contents of the bath of an RPZ-48 electric furnace smelting silicomanganese // Problems of scientific and technological progress in the electrothermal process of inorganic materials.

The disadvantage of this method is the use of high quality raw materials, which currently does not allow to obtain an agglomerate that meets the requirements of ferroalloy production. A change in recent years in the chemical, mineralogical, and particle size distribution of manganese concentrates has led to a decrease in the quality of the sinter and its production indicators. Experience in the production of manganese ferroalloys in powerful closed or sealed electric furnaces indicates that an increase in the number of fine fractions (<5 mm) in charge materials leads to a violation of the stability of the melting mode and an increase in the specific consumption of raw materials and electricity. The amount of fines in the charge is largely determined by the strength characteristics of the sinter.

It is known the production and use of manganese-containing highly basic agglomerate in the smelting of high-carbon ferromanganese in blast furnaces and the production of manganese ferroalloys in high-power sealed electric furnaces is an effective way to reduce material and energy consumption in the production of manganese ferroalloys (see Velichko B.F., Gavikrilov V.A., Gas, M.I., Grishchenko S.G. et al. // Metallurgy of Manganese of Ukraine // Kiiv: Technika, 1996. - 472 p .; Gasik M.I., Lyakishev N.P. // Theory and Technology of Ferroalloy Electrometallurgy in // SP Intermet Engineering. 1999. - 764 p.). Summarizing the results of research and industrial experience in the production of manganese sinter (see Safonov B.M., Murakhovsky V.V. // Development of the production of manganese ferroalloys in electric furnaces // Steel, 1983. No. 5. - 5-7 pp .; Nezhurin V .I., Karmanov ES, Kucher IG // Gasdynamics study of the contents of the bath of the RPZ-48 electric furnace smelting silicomanganese // Problems of scientific and technological progress in the electrotherm of inorganic materials. Abstracts of the report of the Republic of Scientific and Technical Conference. Dnepropetrovsk : 1989. - 30-31 p .; Velichko B.F., Gavrilov V.A., Gasik M.I., Grishchenko S.G. et al. // Metallurgy of Manganese of Ukraine // Kiiv: Technika, 1996. - 472 p .; Gasik M.I., Lyakishev N.P. // Theory and Technology of Electrometallurgy of Ferroalloys // SP Intermet Engineering. 1999. - 764 p .; Gasik M.N., Zubanov V.T., Scherbitsky B.V. et al. // Production of fluxed manganese sinter and smelting of high-carbon ferromanganese // Steel. 1982. No. 9. - 51-53 p .; Utkov V.A. // Highly basic agglomerate. // M .: Metallurgy. 1977 - 156 pp.), It must be noted that in modern conditions the disadvantage is that the well-known technological proposals do not provide an increase in the productivity of sinter machines in the production of manganese sinter and the necessary strength properties of fluxed manganese sinter.

Known methods for sintering fluxed manganese agglomerate with high mechanical strength and high moisture resistance.

A feature of the technology is the use of dolomite fired at 1600-1800 ° С in the sinter charge and the use of fired dolomite in the production of fluxed manganese agglomerate (see Velichko B.F., Gavrilov V.A., Gasik M.I., Grishchenko S.G. and etc. // Metallurgy of manganese of Ukraine // Kiev: Technika, 1996. - 472 p .; Gasik M.N., Zubanov V.T., Scherbitsky B.V. et al. // Production of fluxed manganese agglomerate and smelting of high-carbon ferromanganese // Steel. 1982. No. 9. - 51-53 p.) The disadvantage of these measures is a significant complication of technological energy production line, and energy costs increase by 350 kg of fuel equivalent / t of dolomite. In addition, the production of highly basic manganese agglomerate necessitates the introduction of high-quality manganese concentrate with silica content of less than 10% into the sinter mixture.

The closest analogue of the proposed method for the agglomeration of manganese raw materials is a known method for producing manganese-containing complex flux, including dosing, mixing, granulating a mixture consisting of limestone, solid fuel, manganese-containing raw materials, and sintering the mixture by vacuum agglomeration. In the proposed method for the production of high manganese flux, the pelletizing process is carried out by sequentially rolling on limestone particles with a grain size of 0-3 mm, first a mixture of fuel with low-silicon iron-containing material, and then manganese-containing wastes of ferromanganese production (see AS No. 1708893, С22В 1/24 , 1992). This method is taken as a prototype.

The production experience according to the proposed technology showed that when co-rolling low-siliceous iron-containing components and solid fuel onto limestone particles with a grain size of 0-3 mm, it is not possible to avoid the formation of refractory dicalcium calcium silicate with a melting point of 2130 ° C (2CaOSiO ₂ ) due to close contact of the fuel ash ( SiO ₂ ) and CaO particles. Due to the formation of 2CaOSiO _{2, the} amount of melt decreases, its viscosity deteriorates, and the productivity of the installation decreases. In addition, in order to avoid additional crushing of waste from limestone of mining enterprises with a grain size of 0-5 mm without additional grinding and screening to a particle size of 0-3 mm, the amount of clumping class with a grain size of 1-5 mm will increase due to the use of limestone without additional crushing operations in the charge, which will allow more evenly distribute the crumpled material in the first and second stage of granulation.

The problem to which this invention is directed is to improve the quality of the product, increase the specific productivity and reduce the consumption of solid fuel for the sintering process.

The essence of the invention lies in the fact that in the method of agglomeration of manganese raw materials, including dosing, mixing, granulating a mixture consisting of limestone, solid fuel, manganese-containing raw materials, and sintering the mixture under pressure, the feature is that low-silica iron-containing material is additionally introduced into the mixture , the quality of which is used as a slurry of steelmaking or scale, and the granulation process is carried out by sequentially rolling particles of limestone with a particle size of 5-0 mm at first small iron-containing siliceous material and then a mixture of manganese-containing materials and solid fuel.

According to the proposed method, the preparation of the mixture for sintering under pressure of high manganese flux is carried out in two stages. At the first stage, dosing, mixing and granulation of a mixture of fluxes, low-silicon iron-containing material is performed. As a low-siliceous iron-containing component of the charge, scale or slime of steelmaking is used. The granulation process is carried out by rolling particles of limestone or a mixture of limestone and dolomite with a particle size of 5-0 mm low-siliceous iron-containing waste. At the second stage of preparation of the charge, a mixture of manganese-containing waste or poor manganese ores with a particle size of less than 5 mm and solid fuel with a particle size of 5-0 mm is rolled onto the formed granules of the mixture.

The proposed technology separates a silica-rich mixture of manganese-containing charge and solid fuel from charge granules, consisting mainly of flux mixture particles and low-silicon iron-containing material, which in the sintering zone form fusible ferrite-calcium melts and impregnate a rolling layer of manganese-containing silicon-containing materials.

The combination of the above factors and agglomeration under pressure contribute to the production of high manganese flux with improved quality, high productivity of sinter plants and with lower consumption of solid fuel for the sintering process.

When conducting experiments to test the technology of agglomeration of high-manganese flux under pressure, we used charge materials shown in Table 1.

Table 1 Material Content% Fe Mn SiO ₂ Cao MgO Al ₂ O ₃ p.p.p. Sludge Oxygen Converter Production 64.0 0.20 1.89 10.40 1.15 0.96 1.24 Manganese-containing sludge 4.70 27.0 16,0 9.50 0.65 0.50 10.7 Limestone 0.30 0.14 0.40 53.5 0.74 0.05 42.50

Table 2 shows the technological indicators of the sintering process of high manganese flux with different methods of agglomeration.

table 2 Indicators Known Methods The proposed method Vacuum technology method Pressure sintering method Pressure sintering method Depression under the charge layer, kPa 10.0 Pressure over the charge layer, kPa 117.8 117.8 Fineness of limestone or mixture with dolomite, mm 3-0 3-0 5-0 The content of manganese-containing sludge,% 9.40 9.40 9.40 The solid fuel content in the mixture,% 9.45 6.93 5.50 Specific productivity, t / m ² h 0.95 5.28 6.50 Vertical sintering speed, mm / min 27.0 125.0 145.0 Strength, FR> 5 mm
fr. <0.5 mm 69.0
5.7 94.1
3.2 96.0
2,4 Navy content in the Navy 3.9 5.85 5.95

The specific productivity of the sinter plant using the proposed technology for sintering high manganese flux is 5-6 times higher than that of the prototype, the mechanical strength of the product increased in the yield of the fraction of more than 5 mm from 69.0 to 94.1%, the consumption of solid fuel decreased by 26.7% .

In Russia, in the absence of exploited manganese deposits and enterprises for the production of ferromanganese alloys in sealed electric furnaces, it is necessary to organize the use of technogenic reserves of manganese sludge and blast furnace dust from OJSC Kosogorsky Metallurgical Plant and OJSC Alapaevsky Metal Plant, as well as screenings of manganese ores from Russia and Kazakhstan. From manganese-containing wastes and poor manganese ores, it is proposed to produce highly basic manganese-containing flux for blast furnaces, ferroalloy electric furnaces and steelmaking.

Literature

1. Development of the production of manganese ferroalloys in electric furnaces. / Safonov B.M., Murakhovsky V.V. // Steel, 1983. No. 5. - 5-7 s.

2. The study of gas dynamics of the contents of the bath furnace RPZ-48, smelting silicomanganese. / Nezhurin V.I., Karmanov E.S., Kucher I.G. // Problems of scientific and technological progress in the electrothermy of inorganic materials. Abstracts Republic Scientific and technical conference. Dnepropetrovsk: 1989 .-- 30-31 p.

3. Metallurgy of manganese of Ukraine. / Velichko B.F., Gavrilov V.A., Gasik M.I., Grishchenko S.G. et al. // Kiiv: Technika, 1996 .-- 472 p.

4. Theory and technology of electrometallurgy of ferroalloys. / Gasik M.I., Lyakishev N.P. // JV Intermet Engineering. 1999 .-- 764 p.

5. Obtaining fluxed manganese sinter and smelting of high-carbon ferromanganese. / Gasik M.N., Zubanov V.T., Scherbitsky B.V. et al. // Steel. 1982. No. 9. - 51-53 s.

6. Utkov V.A. Highly basic agglomerate. // M .: Metallurgy. 1977-156 p.

7. Copyright certificate No. 1708893, С22В 1/24. A method of obtaining a manganese-containing complex flux / Khaidukov V.P., Dudikov V.A., Zevin S.A., Grekov V.V., Naumenko V.V., Karpenko E.V. // publ. 01/30/92, bull. Number 4.

Claims (1)

A method of agglomerating highly basic manganese-containing raw materials, including dosing, mixing, granulating a mixture consisting of limestone, solid fuel, manganese-containing raw materials and sintering a mixture under pressure, characterized in that low-silica iron-containing material is additionally introduced into the mixture, for which sludge is used for steelmaking or scale and the granulation process is carried out by sequentially rolling on particles of limestone with a particle size of 5-0 mm initially low-silicon iron aschego material and then a mixture of manganese-containing materials and solid fuel.