Authorization required.

The main areas of research

- Mathematical and physical modeling of heat and mass transfer processes in metallurgical units.

- Physico-chemical bases of complex use of iron ore mineral raw materials.

- Development of methods for assessing the quality of multicomponent iron ore and coke, and their impact on the efficiency of blast furnace smelting.

  1. The method of analytical investigation of the phenomena of the domain process
  2. Optical microscopy
  3. Mechanical tests
  4. Mathematical modeling of pyrometallurgical processes
  5. Direct iron recovery technologies
Vitkina, Galina Yu
Galina Vitkina
Head of Laboratory
Dmitriev, Andrey N
Andrey Dmitriev
Principal researcher
Leontyev, Leopolyd Igorevich
Leopolyd Leontyev
Principal researcher
Tsymbalist, Mikhail M
Mikhail Tsymbalist
Senior Researcher
Zolotih, Maksim Olegovich
Maksim Zolotih
Lead Engineer
Nechkin, Georgiy Aleksandrovich
Georgiy Nechkin
Lead Engineer
Burova, Yuliya Evgenyevna
Yuliya Burova 🥼 🤝 🔍
Student

Research directions

A system has been developed to control the heat of the refractory lining of the blast furnace furnace, designed to prevent emergencies.

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A system has been developed to control the heat of the refractory lining of the blast furnace furnace, designed to prevent emergencies.
A mathematical description, algorithm and computer program for calculating two-dimensional temperature fields in any vertical and horizontal section of the furnace furnace lining have been developed.

Theoretical substantiation and development of methodological bases for assessing the influence of metallurgical characteristics of iron ore and coke on the efficiency of blast furnace smelting

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Theoretical substantiation and development of methodological bases for assessing the influence of metallurgical characteristics of iron ore and coke on the efficiency of blast furnace smelting
A new methodology for assessing the influence of metallurgical characteristics of iron ore and coke on the efficiency of blast furnace smelting is proposed, including laboratory studies to determine the metallurgical characteristics of iron ore and coke, an analytical study of the influence of these characteristics on the efficiency of blast furnace smelting using mathematical models, pilot and industrial tests.

The method of analytical investigation of the phenomena of the domain process

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The method of analytical investigation of the phenomena of the domain process
The development provides for two-dimensional control and prediction of gas dynamic and temperature fields in any vertical section of the furnace when changing the parameters of the blast and loading systems, charge composition and quality of iron ore raw materials, structural elements (height and diameter of the tuyeres, volume and profile of the furnace). The method can be used to analyze the operation of blast furnaces, in particular in case of deviations from the normal mode, to make recommendations for improving work efficiency, to develop melting modes for various iron ore raw materials, and to develop control and management systems for blast furnace smelting.

The development of the physico-chemical foundations of the technology of processing ferrous vanadium titanium magnetite ores to produce vanadium cast iron and titanium slag on the example of the Kachkanar deposit itself.

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The development of the physico-chemical foundations of the technology of processing ferrous vanadium titanium magnetite ores to produce vanadium cast iron and titanium slag on the example of the Kachkanar deposit itself.
The phase composition and metallurgical properties of the pelletized iron ore raw materials (pellets) and blast furnace products obtained during laboratory studies (reducibility, strength, softening and melting temperatures of pellets, the viscosity of blast furnace slags is calculated), as well as their mineralogical features. A scheme has been proposed for the phased transfer of the blast furnaces of EVRAZ NTMK JSC to the smelting of ores from the Kachkanar deposit proper.

Publications and patents

Dmitriev A.N., Smirnova V.G., Vyaznikova E.A., Vit’kina G.Y., Smirnov A.S.
2023-12-29 citations by CoLab: 0 Abstract
Burnt pellets must retain their strength from the moment they are taken out of an induration machine until they are loaded into a blast furnace. One of the indicators of the burnt pellets’ strength is the compressive strength, i.e. the ultimate force. In experiments to determine compressive strength, the main type of fracture is occurrence and development of cracks that pass through the core center of pellets (where the maximum radial tensile stresses present) or near it. The paper presents the requirements for static compression strength imposed by blast furnace production to iron ore pellets. Using an optical and scanning electron microscope equipped with an energy-dispersive microanalyzer, we analyzed the relationship of structural components and pores in the core of burnt unfluxed iron ore titanomagnetite pellets with the ultimate force under static compression. By scanning electron microscopy and X-ray spectral microanalysis, it was established that the core of pellets is a multiphase material, and its main phases are titanomagnetite, magnetite, titanohematite, hematite and aluminosilicate binder. Optical microscopy made it possible to establish the microstructure of the pellet core, which has three types of microstructures: non-oxidized core (magnetite or titanomagnetite), partially oxidized core – around (magnetite or titanomagnetite) hematite grains (titanohematite) and oxidized core (hematite and titanohematite). The main factors for obtaining pellets with an ultimate force of more than 2.5 kN/pellet according to the requirements of blast furnace production are: the number of closed macropores and the number of large grains in the core. It is shown that with an increase in the number of closed macropores and the number of large grains in the core, the ultimate force is reduced from 3.5 kN to 0.87kN/pellet.
Dmitriev A.N., Vyaznikova E.A., Vitkina G.Y., Alektorov R.V.
2023-12-12 citations by CoLab: 0 Abstract
The initial and final softening (melting) temperatures of redesigned iron ore agglomerates with basicities from 1.2 to 3.0, obtained under laboratory conditions, were investigated. The chemical and phase compositions of the laboratory agglomerates, their microstructures and local chemical compositions, the temperatures at the beginning and end of softening (melting), and the temperature interval of softening were studied. Dependencies of the influence of the basicity of iron ore agglomerates on their softening temperature interval, depending on the proportion of phase components, were obtained. It is shown that as the basicity and proportion of silicoferrite SFCA phases increase, the temperatures at the beginning and end of the softening increase and reach a maximum of 1200 and 1312 °С, respectively (at the basicity of the agglomerate of 1.8), after which the temperatures decrease. Simultaneously, the softening interval increased from 73 to 112 °C.
Dmitriev A.N., Vyaznikova E.A., Vitkina G.Y., Karlina A.I.
2023-09-22 citations by CoLab: 3 PDF Abstract
To study the influence of sinter basicity on the microstructure, phase composition, and physicochemical and metallurgical properties, samples of agglomerates with different basicities were sintered and investigated. A comprehensive study of the structure, composition, chemical, and metallurgical properties of the sinter was conducted, and the optimum values for these properties were determined. The results of the mineralogical transformations that occurred during the sintering process are also presented. The magnetite contained in the concentrate partially dissolves in the silicate component and flux during agglomeration, forming a complex silicate SFCA with the general formula M14O20 (M–Ca, Si, Al, and Mg), which is the binder of the ore phases of the agglomerate. The proportion of ferrosilicates of calcium and aluminum in the sinter depends on the basicity of the sinter charge, and the morphology of the SFCA phase depends on the cooling rate of the sinter. The more CaO in the sinter charge, the more SFCA phase is formed in the sinter, and slow cooling results in the growth of large lamellar and dendritic SFCA phases.
Dmitriev A.N., Vyaznikova E.A., Vitkina G.Y., Alektorov R.V.
2022-11-14 citations by CoLab: 2 Abstract
Strength characteristics of iron ore agglomerates of various basicity (mechanical strength and abrasion resistance, thermomechanical strength) have been investigated. The chemical and phase compositions of iron ore agglomerates, their microstructure and local chemical composition were analyzed. Dependences of the strength characteristics of iron ore agglomerates of various basicity on the morphology of silicate bond have been obtained. Dependences of influence of basicity of iron ore agglomerates on their strength characteristics depending on the proportion of phase components are obtained. It has been shown that an increase in the proportion of stabilized silicoferrite (SFCA) in the composition of agglomerates has a positive effect on their thermomechanical strength, which will increase the productivity of the blast furnace and significantly reduce the emission of dust.
Vitkina G., Dmitriev A., Vyaznikova E., Alektorov R.
2022-01-18 citations by CoLab: 2 Abstract
The structure of industrial agglomerates with various compositions and metallurgical characteristics are investigated in the paper. Microstructure of the agglomerates was analyzed by optical microscopy. X-ray diffraction analysis showed the presence of the main phases – magnetite, hematite and silicoferrite bond. A silicoferrite bond (so-called SFCA) is described by a compound with the general formula M14O20, where M is Ca, Si, Fe, Al, Ti. According to ISO 13930, studies have been conducted to determine the index of LTD (strength at low temperature reduction). It is shown that the change in the composition of SFCA from silicate to ferritic under the condition of increasing the basicity of the agglomerate leads to an increase in the strength at low temperature reduction. An increase in the proportion of stabilized silicoferrite in the agglomerate has a positive effect on the index of LTD, which will further increase the productivity of the blast furnace and significantly reduce dust emission.
Dmitriev A.N., Smorokov A.A., Kantaev A.S., Nikitin D.S., Vit’kina G.Y.
2022-01-01 citations by CoLab: 0 Abstract
Titanium dioxide is the most common titanium-containing product on the world market, with increasing demand. The global consumption of TiO2 is 7–7.5 million tons annually. Titanium dioxide is mainly obtained from ilmenite and rutile concentrates. China, USA, Germany, UK, Mexico, and Saudi Arabia are the largest TiO2 producers. Alongside with the natural sources of titanium, there are man-made sources. These sources include titanium-containing slag obtained as a result of pyrometallurgical processing of ores and concentrates containing titanium dioxide. These slags, in addition to titanium dioxide, contain silicon in the form of dioxide, silicates or aluminosilicates, whose chemical processing is difficult due to a high melting point thereof (higher than 2000°C) and to their chemical stability in mineral acids (sulfuric, nitric, hydrochloric ones). Processing of such raw materials is carried out by classical chlorine-based and sulfuric-acid-based methods. The fluorides in industry are used in the production of aluminum, zirconium, uranium, beryllium, niobium, etc., which indicates the possibility of using fluoride methods for titanium slag processing. The paper is devoted to the consideration of a method for producing titanium dioxide based on the use of ammonium hydrodifluoride NH4HF2 that exhibits a high reactivity with respect to a number of chemically resistant oxides (the oxides of silicon, titanium, aluminum, etc.). The fluoroammonium method for processing titanium slag using NH4HF2 involves slag decomposition in NH4HF2 melt followed by the sublimation of silicon admixture. The purification from iron, aluminum and other impurities is performed using a solution of NH4HF2. The further precipitation of titanium followed by the precipitate treatment with the use of AlCl3 and ZnCl2 solutions with the subsequent calcination makes it possible to obtain a rutile modification of titanium dioxide.
Dmitriev A.N., Vyaznikova E.A., Vitkina G.Y., Alektorov R.V., Shubin A.B.
2021-12-17 citations by CoLab: 3 Abstract
Metallurgical characteristics of iron ore agglomerates of various basicity (reducibility, strength after reduction (LTD+6.3), temperatures of the beginning and ending of softening) have been investigated. The phase composition (XRD) of iron ore agglomerates and their microstructure were analyzed by optical microscopy. Various dependences of influence of the basicity of iron ore agglomerates on their metallurgical characteristics with respect to the proportion of phase components that have been obtained. It has been shown that an increase in the proportion of stabilized silicoferrite (SFCA) in the agglomerate has a positive effect on their strength after reaction, which will further increase the productivity of the blast furnace and significantly reduce dust emission.
Dmitriev A.N., Vitkina G.Y., Alektorov R.V.
2021-12-17 citations by CoLab: 0 Abstract
The paper considers the theoretical foundations of softening of iron ore materials in a blast furnace (the so-called ‘cohesion zone’). The dependences of the temperature range of softening of iron ore materials (the temperatures of the beginning and ending of softening) on the degree of reduction are calculated and experimentally obtained. Physical modelling of the softening process of reduced iron ore materials was carried out using the Russian State Standard No 26517-85. The results of calculations of the location and shape of the cohesion zone in the blast furnace for iron ore materials with different metallurgical characteristics are presented.
Dmitriev A.N., Smirnova V.G., Vyaznikova E.A., Dolmatov A.V., Vit'kina G.Y.
2021-12-10 citations by CoLab: 2 Abstract
The burned pellets must retain the strength from the time they come off the roasting machine until they are loaded into the blast furnace. One indicator of the strength of burned pellets is the compressive strength, i.e., the maximum applied load at which the iron-ore pellet completely collapses. The paper studies the character of destruction of burned iron-ore titanomagnetite pellets of fraction 10 - 16 mm in the static compression test according to the Russian State Standard 24765-81. It is shown that the main type of destruction during the test is the emergence and development of plane cracks passing through the center of the magnetite core, where the maximum radial tensile stresses act or in the immediate vicinity. In some cases, the trajectory of one of the destructive cracks deviates from the above plane and envelopes the magnetite core. Obviously, this is due to the presence of a second area of tensile stress concentration at the boundary of the magnetite core and the hematite shell, formed during cooling of the pellets, due to differences in their mechanical and thermophysical properties. As a result, the final structure of pellets is characterized by the presence of two zones -peripheral hematite and central magnetite. The role of the relative size of the magnetite core on the compressive strength of burned pellets has been determined. It was established that the strength characteristics of the pellet increase with a decrease in relative size of the magnetite core. During the process of magnetite complete oxidation (when the whole volume of the pellet consists of hematite), the maximum level of the pellets compressive strength can be: the maximum destructive force - 3300 N, destructive energy - 0.55 J, mass destructive energy - 0.18 J/g.
Dmitriev A.N., Smorokov A.A., Kantaev A.S., Nikitin D.S., Vit’kina G.Y.
2021-04-09 citations by CoLab: 5 Abstract
Titanium dioxide is the most common titanium-containing product on the world market, and the demand for it is increasing. The global consumption of TiO2 is 7 – 7.5 million tons annually. Titanium dioxide is mainly obtained from ilmenite and rutile concentrates. The largest producers are China, USA, Germany, UK, Mexico, and Saudi Arabia. In addition to the natural resources of titan, there are man-made sources. This type of resource includes titanium-containing slags obtained as a result of pyrometallurgical processing of ores and concentrates containing titanium dioxide. These slags, in addition to titanium dioxide, contain silicon in the form of dioxide, silicates or aluminosilicates, whose chemical processing is difficult due to their high melting point (more than 2000 °C) and the chemical stability of these compounds in mineral acids (sulfuric, nitric, hydrochloric). Processing of such raw materials is carried out by “classical” chlorine and sulfuric acid methods. The use of fluorides in industry is realized in the production of aluminum, zirconium, uranium, beryllium, niobium, etc., which indicates the possibility of using fluoride methods for titanium slags processing. The article discusses a method for producing titanium dioxide based on the use of ammonium hydrodifluoride NH4HF2 , which has a high reactivity to a number of chemically resistant oxides (oxides of silicon, titanium, aluminum, etc.). The fluoroammonium method for processing titanium slag using NH4HF2 involves slag decomposition of in NH4HF2 melt followed by silicon admixture sublimation. Cleaning from iron, aluminum and other impurities is carried out using a solution of NH4HF2. Further precipitation of titanium with treatment of the precipitate by AlCl3 and ZnCl2 solutions followed by calcination allows to obtain a rutile modification of titanium dioxide.
Dmitriev A.N., Vitkina G.Y., Alektorov R.V., Vyaznikova E.A.
2021-03-02 citations by CoLab: 3 Abstract
The metallurgical characteristics of pellets (reducibility, strength after reaction, softening start and end temperatures), phase composition (X-ray phase analysis), and porosity were studied. Blast furnace smelting parameters were calculated using laboratory pellets with different basicities and degrees of metallization. Pellets were obtained from complex titanium-magnetite ores. The vanadium extraction of this ore into metal did not exceed 10 % during smelting of metallized pellets in an arc steelmaking furnace, but special techniques could raise this to 85 %. According to calculations from the Institute of Metallurgy of the Ural Branch of the Russian Academy of Sciences (IMET UB RAS), vanadium extraction up to 80–90 % can be achieved by using high-base and partially metallized pellets. The influence of changes in the composition and metallurgical characteristics of titanomagnetite pellets with increasing basicity (especially relative to strength after reduction) should be taken into account.
Vitkina G.Y., Dmitriev A.N., Alektorov R.V.
Abstract The paper presents the results of studies of the chemical, phase composition and metallurgical characteristics of titanomagnetite sinter. The iron ore used in blast furnaces of JSC ‘EVRAZ NTMK’ is titanomagnetite sinter obtained from ores of the Gusevogorsky deposit. Samples of sinter with different basicities as well as with addition of binding polymers in the amount of 300 and 500 g per ton of sinter were investigated. The results of industrial tests of the production and blast furnace smelting of sinter with different basicities and additives of binding polymers are presented on the example of the operation of blast furnaces no. 5 and 6 of JSC ‘EVRAZ NTMK’. It was shown that an increase in the basicity of the sinter from 2.1 to 2.4 and the introduction of a polymer binder (in the amount of 500 g per ton of sinter) positively affect the complex of sinter metallurgical characteristics – durability after reduction, reducibility, softening and melting temperatures, and also decrease the coke rate in blast furnace smelting by 1.0–1.2%.
Dmitriev A.N., Alektorov R.V., Vitkina G.Y., Petrova S.A., Chesnokov Y.A.
2020-03-31 citations by CoLab: 3 Abstract
The reducibility of titanomagnetite iron ore materials (agglomerate, pellets) with various TiO2 contents are studied. The mineralogical features of agglomerate and pellets before and after reduction are investigated. Calculations of technical and economic indicators of blast furnace smelting using iron ore materials with different TiO2 contents are carried out. It is shown that an increase in the content of titanium dioxide in pellets and agglomerate (with an increase in the amount of concentrate introduced into them) does not change the quality of iron ore preparation for blast furnace smelting.
Dmitriev A.N., Petukhov R.V., Vitkina G.Y., Vyaznikova E.A.
2019-02-28 citations by CoLab: 2 Abstract
Questions regarding the oxidizing roasting of raw iron ore materials (agglomerate and pellets) are studied. Features of the phase structure of raw iron ore materials containing titanium and vanadium are discussed. Reducibility, durability, and temperatures of the softening and melting of metallurgical raw iron ore materials are studied in vitro. Object of research – titaniferous ores with various titanium dioxide content. The behavior of agglomerate and pellets in a blast furnace are studied, as well as the influence of their physical and chemical properties on heat and mass transfer processes using a mathematical model of the blast furnace process [1].
RU2022665099,

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620016, г. Екатеринбург, ул. Амудсена, 101
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