Статті КЕМ ім. Гасика (ДМетІ)

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Coordinated Control of the Composition of 01yut Steel and Deformation Processing Modes to Achieve Specified Mechanical Properties
(National Metallurgical Academy of Ukraine, Ukrainian State University of Science and Technologies, Dnipro, 2024) Velychko, A. G.; Kamkin, V. Yu.; Proidak, Yurii S.
ENG: Purpose: to investigate the influence of the chemical composition of steel on the output from the chipboard and to establish rational parameters of deoxidation and deformation to ensure the specified values of mechanical properties. Methods: physicochemical modeling, thermodynamic calculations, experimental studies. Results: the carbon content and the degree of oxidation of the semi-finished product from the electric furnace for further vacuum treatment to obtain low-carbon steel were determined. With an increase in the oxygen flow rate supplied to the chipboard and exceeding the value required for the stoichiometry of fuel combustion reactions, the oxidation of the semi-finished product increases. To avoid the formation of calcium silicates, it is necessary to have an active oxygen content below 2.5 ppm, which is ensured by the residual content of dissolved aluminum in steel of 0.025-0.027%. Scientific novelty: The use of complex deoxidizers in steel production allows using the synergistic effect of the joint deoxidizing action of deoxidizing elements. The use of the methodology of physicochemical modeling made it possible to effectively solve the problem of predicting the properties of steel. To study the influence of modifier elements, as well as the main alloying components, a number of parameters characterizing the state of the alloy as a whole (Zу, d) were calculated. Based on information on the significant influence of the chemical composition of the steel on its properties, a database of 150 compositions was prepared to determine the optimal composition of ultra-low-carbon steels of the 01ЮТ, 01ЮТА type by the method of physicochemical modeling. Based on the calculations, the concentrations of elements for steels of the 01ЮТ and 01ЮТА grades were selected.
Improved Heat-Insulating Products for Ingot Hot-Tops in Molds without Extensions
(Ukrainian State University of Science and Technologies, Dnipro, 2025) Akreiev, V.; Cherenkov, D.; Prykhodko, S.; Melnyk, S.; Ovcharuk, Anatolii M.
ENG: The fundamental principle of proper ingot solidification in metal molds - hop top part of ingot should cool and solidify slowly than the ingot body. To achieve this, typically hop top parts of ingots are insulated with special thermal insulation products. They are mounted either directly on the inner surface of the mold or installed in special hop top extensions of the mold. This approach effectively directs shrinkage defects away from the usable ingot section into hop top cut zone. For different steel grades (alloys), depending of the application, ingot design, and casting method, hop top cut ranges from 8% to 16% of the total ingot mass. This article presents experience in using an advanced thermal insulation insert design, which enables higher part of usable ingot metal, prevents subhead cracks in the ingot, simplify and lighten the lining of ingot hop top.
Improvement of Quality and Improvement of Technology of Production of Economic Alloyed Steels for Power Engineering
(НМетАУ, Дніпро, 2021) Proidak, Yurii S.; Pidhоrnyi, Serhii; Tregubenko, Gennady; Polyakov, G.; Pidyash, Lyubov
ENG: Purpose. Investigate the effect of complex microalloying with nitrogen, titanium and aluminum on the structure and properties of cast steels at elevated temperatures. Methodology. Methods of optical microscopy were used for metallographic analysis of the microstructure of steels. The mechanical properties at room and elevated temperatures were determined for static tension, crease and impact bending. Results. The technology of carbonitride strengthening of silicon-manganese production steels has passed pilot testing. The results of mechanical tests indicate a favorable complex effect of nitrogen, titanium and aluminum on the properties of 20GSL steel in the entire range of operating temperatures. Scientific novelty. For the first time, the effect of nano-dispersed carbonitride phases (TiN, AlN) on the mechanical properties of low-alloy silicon-manganese steel of the GSL type at elevated temperatures (250-4500C) has been investigated. Practical value. The use of carbonitride technology for strengthening silicon-manganese heat-resistant electric steel provides an increase in operational reliability, an increase in the service life and reduce the metal consumption of equipment for power engineering.
Improvement of the Process of Conducting Arc-Free Ferronickel Melting in a Six-Electrode Furnace
(Elsevier/SSRN, 2021) Bezugliy, Anatolii V.; Nikolenko, Anatolii V.; Shevchenko, D. V.; Ovcharuk, Anatolii N.; Kuvaev, Viktor Iu.; Bezugliy, V. A.; Zamkovoy, O. V.
ENG: Purpose. The aim of the authors is to find a technical solution to effectively control the appearance of an arc discharge in the subelectrode space of each of the six electrodes in submerged-arc furnaces from operational point of view. Methodology. A scheme was drawn up for modeling of the furnace circuit of a six-electrode furnace, which made it possible to obtain the zero point offset voltage and control its third harmonic and other components. For this purpose, two three-phase systems were created in the electrical circuit of the six-electrode furnace, consisting of half-phases of odd and even electrodes. For each of these systems, an artificial symmetric "star" was created separately. The neutral offset voltage for each of the systems was measured between the star zero point and the conductive hearth. Findings. Analysis of the harmonic composition of the shape of the neutral offset voltage curve, created by using an artificial symmetric star, made it possible to obtain a number of information (dependencies) that can be used in control algorithms. The proposed measuring scheme was tested on operation industrial six-electrode furnace of the Pobuzhsky Ferronickel Plant. During the melting, arcs were artificially created under the electrodes. Wherein: 1) the presence of an arc discharge was confirmed by the appearance of the third harmonic of the zero point offset voltage; 2) phase shifts of the first harmonic unambiguously indicated to the electrode with an arc discharge. Practical value The proposed method for monitoring the presence of electric arcs under the electrodes can be used to control ore-thermal furnaces both independently and as an addition to the already used systems for monitoring and controlling the electric mode of six-electrode furnaces.
Modeling of Temperature-Concentration Ranges of Phase Stability and Liquidus Surface in the Ternary Fe–P–C System and Phase Composition Experimental Study
(Ukrainian State University of Chemical Technology, Dnipro, 2023) Proidak, Andrii Yu.; Hasyk, Mykhailo I.; Proidak, Yurii S.; Bezshkurenko, Oleksii G.
ENG: This paper reports thermodynamic properties and phase equilibria in the iron-phosphorus-carbon system for developing a technology for smelting ferrophosphorus as well as for utilizing them in the processes of phosphorus-alloying of metals. According to the results of thermodynamic calculations, we plotted a ternary Fe–P–C phase equilibrium diagram (liquidus surface) in the form of graphical dependences, which indicate the concentration fields of phase coexistence. The results of simulation allowed finding out five nonvariant points, three of which are new: E1eutectic (teutectic=12170 °C), U1 peritectic (tperitectic=1095 °C), and E3 eutectic (teutectic=3380 °C). The experimental studies of the phase composition of ferrophosphorus showed that the phosphorus microstructure is represented by Fe3P phosphide, Fe3C carbide, and carbophosphide eutectic. We carried out the thermodynamic calculation of the temperature-concentration ranges of phase stability in the Fe–P–C system that are at equilibrium with the smelts of both the carbon solid solutions and phosphorus ones in α- and γ-iron, FeP, Fe2P, Fe3P phosphides, and graphite. In this study, three previously unknown nonvariant equilibria have been determined: a eutectic equilibrium at 1216.58 °C; a peritectic one with a transformation point at 1095.19 °C; and a eutectic one at a temperature of 337.51 °C. In experiments, we obtained an equilibrium concentration of carbon which decreases in the Fe–P–C system when the content of phosphorus increases. The research findings largely reveal special features of preparation of ferrophosphorus by carbon reduction of phosphorites.
On the 100th Anniversary of the Department of Electrometallurgy
(Ukrainian State University of Science and Technologies, Dnipro, 2025) Sykhoy, K. M.; Proidak, Yurii S.
ENG: The article reflects the origin and development of the electrometallurgical industry in Ukraine. The emphasis is placed on the role of the Department of Electrometallurgy at the Dnipro Metallurgical Institute in this process. The Department of Electrometallurgy was established in 1925. This was facilitated by the leading role of scientists, professors, doctors of technical sciences Telnyi S. I., Khytryk S. I., Hasyk M. I., who made a significant contribution to the development of the electrometallurgical industry in Ukraine and the training of highly qualified specialists. In the article, the key stages of formation and development of electrometallurgy have been outlined, and the crucial role of scientists and teachers of the Department has been stated.
Physical and Chemical Audits and Comparative Analyses of Scrap Remelting Technology Indicators for High-Alloyed Steel with Special Purposes Using the Duplex-Slag Process and the Resource-Saving Mono-Slag Process
(Ukrainian State University of Science and Technologies, Dnipro, 2025) Projdak, Yurii S.; Gorobets, A. P.; Zhadanos, Oleksandr V.; Kamkina, Liudmyla V.; Yaroshenko, Y. O.
ENG: The goal. The research purpose is a physicochemical audit and comparative analysis of the indicators of the technologies for remelting scrap of high-alloy special-purpose steels using a two-slag process and a resource-efficient single-slag process to create an innovative technology for the electric steelmaking process. Methodology. The research used miscellaneous methods and modern equipment for studying the physical chemistry of metallurgical processes, including optical metallography methods on the “Neophot-24” installation, to assess the microstructure of the metal and the mineralogical composition of the slags. Experimental and industrial smelting was carried out to determine the balance of alloying elements by certified chemical and spectral analysis of the metal and slag. Results and scientific novelty. To ensure the rational composition of the slag of reduced basicity during melting, a mixture with the following composition was synthesized from oxides classified as "chemically pure": 50%СаО-35%SiO2-5%Al2O3-5%MgO-5%FeO. This allows for the reduction of the loss of alloying elements and increases the efficiency of remelting. According to the results of the analysis conducted by the requirements of DSTU 8966:2019 regarding the contamination of the metal with non-metallic inclusions and their crystalline and chemical composition, it was found that the vast majority of inclusions are represented by silicates with a size of 7-10 μm. These indicators depend on the size and conditions of crystallization of the ingot. Changes in the content of alloying elements due to the remelting process were analyzed. It was confirmed that the losses of expensive alloying elements (Cr, Mo, W, V) depend not only on their chemical affinity for oxygen but also on the formation of compounds of the type СаО*МеО in the slag, where МеО oxide has an acidic nature of interaction. New knowledge has been obtained regarding the physical properties and phase composition of lime-iron slag of the CrO-FeO-SiO2-(Ме)O system where Me-Mn, Cr, V, Mo. The obtained scientific results significantly complement the research of domestic and foreign scientists due to the novelty of the approach and practical orientation to the needs of specific industries. Practical value. The developed technological solutions for predicting the optimal composition of the metal dump for metal scraps of alloyed special-purpose steels will increase the technical and economic performance of steelmaking in electric furnaces and promote the reuse of valuable materials. This is important in the context of the constant increase in the cost of raw materials and efforts aimed at reducing the impact on the environment, as well as on the sustainable development of Ukraine (solving environmental problems, reducing greenhouse gas emissions, reducing the consumption of ferroalloys, etc.).
Promising Metal-Thermal Technologies for Titanium Production
(Ukrainian State University of Science and Technologies, Dnipro, 2025) Ignatiev, Volodymyr S.; Holovachоv, Artem M.; Kolbin, Mykola O.; Yaroshenko, Ya. O.
ENG: This review discusses existing and new titanium production technologies, their advantages and disadvantages. The current global production of titanium metal is based on the production of titanium sponge by reducing titanium tetrachloride with liquid magnesium and then purifying it by electric arc remelting (Kroll's metallothermal method). The Kroll method has some disadvantages: periodicity of the process, low speed, and high cost of raw materials. The paper analyzes a number of fundamentally new technological schemes for titanium production: magnetism in salt melts; magnetism in a liquefied layer of magnesium particles (TIRO process); sodium jet thermionic (Armstrong process); steam process. In the near future, we can expect a breakthrough in titanium technology that will reduce its cost.
Properties of Railway Wheels Made of Metal with Increased Copper Content
(Printing House “Technologija”, Kaunas, Lithuania, 2024) Proidak, Yurii S.; Chornoivanenko, Kateryna O.; Pikil, O.
ENG: The content of non-ferrous metals and, in particular, copper is limited by numerous standards regulating the chemical composition of steels. Thus, for instance, according to the Ukrainian standard for wheel steel, the residual content of nickel, chromium, and copper should not exceed 0.25% each. According to the international UIC standard, this content should not exceed 0.30% each. The residual copper content according to the Japanese standard is allowed to be not more than 0.35%. Many steelmakers are concerned about the presence of copper due to its red shortness. However, the beneficial effect of Cu on hardenability and transformation kinetics is well-known, enabling the formation of a structure with a high density of dislocations at cooling rates feasible in industrial conditions, thus imparting high initial strength to the matrix. Experimental smelting was conducted in the open-hearth furnaces to obtain 0.15-0.60% of copper in the metal. It was found out that the resistance of slag truck wheels made of metal with increased copper content against the formation of ridge notches, which are the main reason for repairs of these wheels during operation, is significantly higher than that of serial ones.
Regularities of Solid-Phase Reduction of Iron Oxides under Conditions of Combined Chemical-Catalytic and Energetic Influence
(Ukrainian State University of Science and Technologies, Dnipro, 2025) Grishin, Oleksandr M.; Projdak, Yurii S.
ENG: Purpose. The purpose of the work is a physicochemical analysis of the intensification of the process of solid-phase iron reduction under the conditions of the joint influence of catalytic additives and an electromagnetic field (EMF). Methodology. The experiments were conducted in an alternating magnetic field with a frequency from industrial to ultrasonic using the thermogravimetric method. The process of reduction of various iron ore materials was studied in the temperature range of 873-1373 К Results. The results of laboratory experiments indicate the influence of the electromagnetic field and intensifying catalytic additives on the process of solid-phase reduction of various iron ore materials. The non-additivity of the results of the joint influence of additives and an intensifying EMF is shown. The study of the influence of various process parameters on the rate and degree of reduction of iron ore materials is carried out. Scientific novelty. The joint intensifying effect of catalytic additives and EMF on the process of solid-phase iron reduction is experimentally shown. A physicochemical justification of the non-additivity of the joint influence on the kinetics of the reduction process is proposed. Practical significance. Intensification of the processes of solid-phase reduction of iron ore raw materials provides a significant increase in the productivity of direct iron production technologies - process intensification and process productivity.
Research into Phosphate Mineral Composition and waste Phosphorite Ore
(Dnipro University of Technology, 2021) Proidak, Andrii Yu.; Gasyk, Mykhailo; Proidak, Yurii S.
ENG: Purpose. Theoretical and experimental studies of chemical and mineral composition and the structure peculiarities of phosphorites from Ukrainian deposits to define the degree of their suitability for other industries. Methods. The ore chemical composition was determined by conventional (wet) analysis using standard certified chemical reagents. The mineral composition was studied on the scanning electron microscope equipped with the attachment for the energy- dispersive electron microprobe analysis (EMPA) with the software for calculating the chemical composition of the studied sample microvolume. The petrographic analysis was carried out by the traditional methods of microscopic section preparation with subsequent identification and description of the minerals. The microscopic study of the original ore samples aimed at their mineral composition determination was conducted on the Nu optical microscope (Germany) both in transmitted and reflected light. The thin and polished sections prepared using the standard technology were used as samples. In the laboratory environment, the phosphorites were subjected to magnetic dressing in magnetic fields with different intensity. The experiments in the weak field were modelled with the help of the magnetic analyzer while the experiments in the strong magnetic field were modelled on the rotor separator. The flotation dressing method was studied on the laboratory mechanical flotation machine. Findings. It was found that phosphate nodules are rounded mineral formations of irregular shape; they consist of sand bound with the yellow-brown phosphate cement. Ore useful substance is a phosphorus-bearing mineral that by the element chemical composition corresponds to fluorocarbon-hydroxyl-apatite with the dominant content of Ca (45.23%), P (15.67%), and B (27.87%). The results of the integrated petrographic study of the phosphorite samples from the ore body of “Peremoha” area are presented. Originality. The study has revealed that phosphorus-containing substance in the phosphorite samples is the mass that cements barren minerals (mainly quartz, glauconite, calcite and plagioclase). Practical implications. According to the phosphate content level, the phosphorites from Malokamyshevatske, Iziumske and Sinichino-Yaremovske deposits can be treated as minerals for ferrophosphorus smelting.
Research into the Possibility of Producing Ferrosilicoaluminum from Recycled Materials
(Ukrainian State University of Science and Technologies, Dnipro, 2025) Taran, O.; Ovcharuk, Anatolii M.; Maliy, E.
ENG: The technology of electrothermal production of ferrosilicoaluminum using recyclable material from abrasive production has been developed, studied and tested in laboratory and semi-industrial conditions. The following were used as burden components: "old charge" from silicon carbide production, sludge from abrasive electrocorundum and silicon carbide, magnetic fraction from electrocorundum production and gas coal. As a result, an alloy containing 61−69% Al+Si was obtained.
Research of the Ore Reducing Furnaces Electrical Modes for Ferronicel Production
(Ukrainian State University of Science and Technologies, Dnipro, 2025) Shevchenko, D. V.; Ovcharuk, Anatolii N.; Gladkih, V. A.; Bezugliy, Anatolii V.; Nikolenko, Anatolii V.
ENG: The paper presents the results of a study of the electrical modes of ferronickel furnaces OTF-1 and OTF-2 at the Pobuzhsky ferronickel plant. It was found that the furnaces operate in arcless mode. An asymmetrical voltage mode is observed: electrode casing - under, which indicates an unbalanced mode of the furnace. As a result of measurements, a significant transfer of power was detected in the area of the electrical circuit of the 4th, 5th, 6th electrodes. An analysis of the electrical mode of a 48 MVA round ferronickel furnace in the city of Hua-Hua (China) showed that the use of a furnace transformer without a voltage booster and an autotransformer makes it possible to provide the necessary electrical mode of ferronickel furnaces. An analysis of the electrical mode of a 90 MVA round ferronickel furnace in Guatemala showed the possibility of operating these furnaces in a combined mode, i.e. in the presence of an electric arc, which is controlled by the resistance of the electrodes and the power ratio in the electric arc and slag.
Research on the Properties of Ferronickel Production Slags and Development of Technological Schemes for their Enrichment
(Ukrainian State University of Science and Technologies, Dnipro, 2025) Shevchenko, D.; Ovcharuk, Anatolii M.; Nadtochii, Anzhela A.; Prykhodko, S.; Shutov, V.
ENG: Objective. Determination of the physicochemical properties of slags, phase composition, and forms of nickel presence in them, development of enrichment modes and equipment parameters. Research Methods and Equipment. X-ray spectral microanalysis (RSMA) on the SELMI REM-106I installation was used to determine the distribution of nickel between the metallic and oxide phases in the presented slag samples. Dry and wet gravity and magnetic separation using modernized magnetic separators established the possibility of slag enrichment and the distribution of nickel between the enrichment products. Research Results. This work has conducted research on the gravitational-magnetic separation of electro-furnace and refining slags of ferronickel production in the conditions of the Pobuzhsky ferronickel plant. The efficiency of implementing the developed technological schemes in production was shown, providing additional extraction in the amount of 119 tons or 9.8% of the total annual nickel production at the plant. Slag samples were ground in experimental ball mills to fractions of –0.16; 0.16÷1.6 and +1.6 mm and subjected to enrichment by gravity and magnetic separators with a magnetic induction on the drum surface of 0.3-0.6 T (Tesla) of the MBS-300 and MS-500 types with a total metal phase yield of up to 30%. Scientific Novelty. RSMA established that nickel, both in electric furnace granulated slags and in refining slags, is in the metallic phase and is represented by metal nuggets in combination with iron of various shapes and sizes. Enrichment of electric furnace and refining slags by a combined method using a high-intensity magnetic field will allow obtaining a metal concentrate containing 0.9-38% nickel. The combined enrichment method using high-intensity magnetic separators is one of the most promising for enriching both primary mineral raw materials and secondary materials of ferrous and non-ferrous metal production. Practical Significance. The developed and proposed for implementation technological schemes for enrichment of electric furnace slags using the “wet” technology and refining slags using the “dry” technology allow for the utilization of about 1200 tons of nickel per year or the extraction of 31.6% and 94.65% of nickel from slags, respectively.
Studying the Phase Equilibria in MnO-SiO2 System by the Differential Scanning Calorimetry (DSC) Method
(National Academy of Sciences of Ukraine, Publishing House Akademperiodyka, 2022) Proidak, Yurii S.; Gladkykh, V. A.; Ruban, Artem V.
ENG: Introduction. The formation of rational composition of molten slag is critical for smelting of manganese ferroal-loys. From seventy to ninety per cent of manganese ferroalloy slags are presented by manganese and silicon oxides. Information about phase equilibrium in MnO—SiO2 system has an important value for the development of new and the improvement of operating processes of beneficiating and agglomerating manganese raw material, manufacturing manganese ferroalloys, and smelting high-manganese electrical steels. Problem Statement. The analysis of scholarly research data on the diagram of the equilibrium state of MnO—SiO2 system has shown a difference between the temperature of eutectic melting and that of peritectic melting and a fundamental difference in the nature of these two types of melting. The diagram does not show the polymorphic transformation of rhodonite. Purpose. The purpose of this research is to study the behavior of manganese orthosilicate and metasilicate and the eutectic between them for specifying the structure of the MnO—SiO2 system equilibrium state diagram. Materials and Methods. The DSC method has been used to determine the temperature of phase transformations, melting and crystallization, of the samples that correspond to rhodonite (MnSiO3), tephroite with rhodonite (Mn2SiO4 + MnSiO3), and the eutectic located between them in terms of composition. Results. The temperature of tephroite congruent melting, the solidus and the liquidus of rhodonite incongruent melting have been determined more accurately. For the first time, the temperature of rhodonite polymorphic trans-formation at the phase transition γ-MnSiO3↔β-MnSiO3 accompanied with a volume fluctuation of up to 2% has been experimentally established. This has made it poss ible to plot the horizontal line of polymorphic transformation on the MnO—SiO2 system diagram. Conclusions. The obtained data on the equilibrium state of MnO—SiO2 system have given a clear idea of the slag system structure, which allows us to optimize cooling during the manganese agglomerate production; to ratio-nally select the slag melting conditions for the ferrosilicon manganese production; to improve slag thickening after the release of smelting products; to justify slag crystallization behavior for the production of slag-cast products.
Ukrainian Steel and Ferroalloys in 2022-2024: How Russian Aggression Has Impacted on the Work of the Country's Metallurgical Industry
(Ukrainian State University of Science and Technologies, Dnipro, 2025) Gryshchenko, S. G.; Proydak, Yurii S.; Ponomarennko, R. V.; Kravchenko, А. P.; Kalenkov, O. F.; Kudryavtsev, S. L.
ENG: In April 2025, the centennial of the establishment of the Department of Electrometallurgy of the Ukrainian State University of Science and Technology (at the time of its establishment - the Dnipropetrovsk Metallurgical Institute) will be celebrated. It will not be an exaggeration to say that it was the Department of Electrometallurgy, for many of us - the "alma mater", that became the founder of the world-famous school of Ukrainian electrometallurgy, the educator of a galaxy of many thousands of ferroalloy and electric steelmakers who held and hold leading positions at industry enterprises, the developer of many highly efficient technological processes of world class. Congratulating our native department on its anniversary, we sincerely wish to continue to firmly hold the banner of domestic electrometallurgical science in our hands, which is especially important now, in the difficult conditions in which the metallurgical industry of Ukraine found itself with the beginning of large-scale Russian aggression in February 2022. The Ukrainian metallurgy, taking into account the acceleration of Ukraine's European integration with the EU: on June 23, 2022, Ukraine acquired the status of a candidate for membership in the European Union and now we will have to accelerate reforms in order, including in the environmental sphere, to truly enter the European family Maintaining and developing ties with the world metallurgical and ferroalloy community, Ukrainian metallurgists will continue to look for ways to stabilize the situation, first of all - to stop Russian aggression, and in this regard we count on the active assistance and support of our foreign colleagues.
Аналіз стану термічно резервної зони доменної печі при використанні в шихті рудовугільних композицій
(Український державний університет науки і технологій, ННІ ≪Інститут промислових та бізнес технологій≫, ІВК ≪Системні технології≫, Дніпро, 2024) Ванюков, Антон Андрійович; Камкіна, Людмила Володимирівна; Іващенко, Валерій Петрович; Мяновська, Яна Валеріївна; Сазонов, П. О.
UKR: Розглянуто виникнення та існування зон у доменній печі, обумовлене закономірностями теплообміну. У середній зоні доменної печі температура потоку газу, що виходить, залишається відносно постійною і в ній не відбуваються хімічні процеси. Це "термічно резервна зона", верхня частина цієї зони – "хімічно резервна зона" представлена вюститом, який не відновлюється. Резерв цієї зони – утворення газової фази. При добавках у шихту рудовугільних композицій відбувається відновлення оксидів заліза (t=1000 °C) за реакцією Fe2O3+C=Fe3O4+CO2 та газифікації вуглецю СО2+С=2СО (Реакція Будуара). Газова фаза (СО), що утворюється, інтенсивно відновлює оксиди заліза. Композити для доменної плавки виробляються із суміші доменних шламів із добавками цементу. Суміш переробляється рудовугільні котуни або брикети. Доменна плавка на металургійних заводах України, Південної Кореї, Японії показала, що використання рудовугільних композитів є ефективною добавкою в шихту доменної плавки для зниження витрати коксу. В основі ефекту рудовугільного композиту лежить теорія "Тісного контакту" (Coupling Phenomenom) між вуглецевими і залізовмісними матеріалами в окатиші-композиті. Їхня взаємодія відбувається, як показали дослідження, при температурах 250-420°C в атмосфері СО. З урахуванням реакції Будуара температура в термічно резервній зоні доменної печі знижується на 80-200°C. Таким чином, у хімічно резервній зоні – відновлення в'юститу відбувається не при 1000°C, а при 920-800°C і вона зміщується ближче до зон формування чавуну і шлаку. У статті проаналізовано термограми у доменній печі з урахуванням рудовугільних композитів. Хімічно резервна зона розташовується у середині шахти (від поверхні шлаку) 11,2 м. Зі збільшенням витрати композиту в шихті (30%) становище резервної зони знижується з 11,2 до 6,2 м. Ширина між термограмами 1200°C –1400°C є характерною зоною когезії, зі збільшенням витрат композиту знижується з 2,1 м т (без завантаження композиту) до 0,9 м при витраті композиту 30%.
Аналіз якості шихтових матеріалів при виробництві висококремнистого феросиліцію
(НМетАУ, УДУНТ, Дніпро, 2023) Кравченко, В. П.; Гладких, Володимир Андрійович; Аносов, О. В.; Рубан, Артем Володимирович; Рябцев, О. О.
UKR: Феросиліцій виробляють шляхом відновлення кремнію, що міститься у кварциті, твердими вуглецевими відновниками у присутності заліза. Головними компонентами шихти для виробництва феросиліцію є кварцит, вуглецевий відновник та сталева стружка, до яких висуваються жорсткі вимоги по фракції, вмісту шкідливих домішок, електропровідності. Високовідсоткові марки феросиліцію найбільш чутливі до якості відновника. У сучасній металургії відбулись зміни якісних характеристик коксової продукції в наслідок впровадження у доменному виробництві технології пиловугільного палива (ПВП), яке застосовується в доменній плавці як добавка, що призвело до зміни вимог до доменного коксу, а саме – необхідності зниження хімічної активності та збільшення гарячої міцності коксу. Таким чином, одним з можливих напрямків оптимізації технології виплавки феросиліцію в умовах АТ "ЗФЗ" є підбір відновлювальних сумішей, що складаються з різних вуглецевмісних матеріалів та задовольняють вимоги феросплавного виробництва щодо співвідношення показників реакційної здатності (CRI) та міцності коксу після реакції (CSR).
Вибір оптимальної витрати інертного газу при продуванні сталі в 250-тонному сталерозливному ковші
(НМетАУ, УДУНТ, Дніпро, 2024) Акреєв, Володимир В.; Мельник, Сергій О.; Приходько, Сергій В.; Овчарук, Анатолій Миколайович; Губа, Р. М.
UKR: В сучасному світі, під час стрімкого підвищення вимог ринку до «чистоти» сталі та невпинного розвитку сталеливарної промисловості, питання забезпечення якості позапічної обробки набуває особливої актуальності. Чистота сталі завжди була основним завданням для вторинного рафінування у сучасному сталеплавильному процесі на установках «піч-ківш». Від ефективності рафінування значною мірою залежить багато показників технології, таких, як контроль компонентів та складових сталі, видалення шкідливих домішок та включень. Процес рафінування неможливо реалізувати без гомогенізації металу. За цю частину технології обробки відповідає продування сталевої ванни інертним газом, яке в першу чергу, здійснюється за допомогою продувальних пробок, встановлених у продувні вузли в днищі сталерозливного ковша. Робота присвячена визначенню оптимальної витрати інертного газу під час продування сталі в 250-тонному сталерозливному ковші. У футеруванні днища сталерозливного ковша використовуються продувні вузли з щілинними пробками з оптичними індикаторами зносу у вигляді металевого штифта. Виконано комп'ютерне моделювання процесу продування сталі з різною витратою аргону (300 л/хв та 600 л/хв), вказані переваги та недоліки, приділено увагу питанню впливу на футерування.
Визначення часу транспортного запізнення шихти при виплавці марганцевих сплавів у надпотужних феросплавних електропечах
(НМетАУ, УДУНТ, Дніпро, 2024) Гладких, Володимир Андрійович; Рубан, Артем Володимирович; Кузьменко, С. М.; Рябцев, О. О.; Аносов, О. В.; Кравченко, В. П.
UKR: Покращення техніко-економічних показників процесу виплавки феросплавів відбувається за рахунок вирішення питань оперативного керування технологічними процесами, а їх оптимізація пов’язана з використанням надійних практичних вихідних даних. Тому в роботі з метою встановлення кореляційних взаємозв'язків між вихідними параметрами i кінцевими показниками з урахуванням технологічної інерційності процесу запропоновано скореговану методику «транспортного запізнення». Експериментально встановлено час «транспортного запізнення» електропечі РПЗ-63. Практична значущість результатів полягає в отриманні більш достовірних промислових даних залежності впливу опору електрода (RЭ) на продуктивність печі (Пп), питомі витрати електричної енергії (Qп) та коефіцієнт вилучення марганцю у сплав (ηMn).

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