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    Wyświetlanie 1-12 z 12
    Tytuł:
    Comparison the Physico-Chemical Model of Ferrosilicon Smelting Process with Results Observations of the Process under the Industrial Conditions
    Autorzy:
    Machulec, B.
    Bialik, W.
    Powiązania:
    https://bibliotekanauki.pl/articles/351005.pdf
    Data publikacji:
    2016
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    ferrosilicon
    model
    equilibrium
    FEM
    submerged-arc furnace
    Opis:
    Based on the minimum Gibbs Free Enthalpy algorithm (FEM), model of the ferrosilicon smelting process has been presented. It is a system of two closed isothermal reactors: an upper one with a lower temperature T1, and a lower one with a higher temperature T2. Between the reactors and the environment as well as between the reactors inside the system, a periodical exchange of mass occurs at the moments when the equilibrium state is reached. The condensed products of chemical reactions move from the top to the bottom, and the gas phase components move in the opposite direction. It can be assumed that in the model, the Reactor 1 corresponds to the charge zone of submerged arc furnace where heat is released as a result of resistive heating, and the Reactor 2 corresponds to the zones of the furnace where heat is produced by electric arc. Using the model, a series of calculations was performed for the Fe-Si-O-C system and was determined the influence of temperatures T1, T2 on the process. The calculation results show a good agreement model with the real ferrosilicon process. It allows for the determination of the effects of temperature conditions in charge zones and arc zones of the ferrosilicon furnace on the carbothermic silica reduction process. This allows for an explanation of many characteristic states in the ferrosilicon smelting process.
    Źródło:
    Archives of Metallurgy and Materials; 2016, 61, 1; 265-270
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Similarity of Ferrosilicon Submerged Arc Furnaces With Different Geometrical Parameters
    Autorzy:
    Machulec, B.
    Gil, A.
    Bialik, W.
    Powiązania:
    https://bibliotekanauki.pl/articles/356113.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    submerged-arc furnace
    ferrosilicon
    similarity k
    c3
    J1
    Opis:
    In order to determine reasons of unsatisfactory production output regarding one of the 12 MVA furnaces, a comparative analysis with a furnace of higher power that showed a markedly better production output was performed. For comparison of ferrosilicon furnaces with different geometrical parameters and transformer powers, the theory of physical similarity was applied. Geometrical, electrical and thermal parameters of the reaction zones are included in the comparative analysis. For furnaces with different geometrical parameters, it is important to ensure the same temperature conditions of the reaction zones. Due to diverse mechanisms of heat generation, different criteria for determination of thermal and electrical similarity for the upper and lower reaction zones were assumed contrary to other publications. The parameter c3 (Westly) was assumed the similarity criterion for the upper furnace zones where heat is generated as a result of resistive heating while the parameter J1 (Jaccard) was assumed the similarity criterion for the lower furnace zones where heat is generated due to arc radiation.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 4; 2343-2347
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Application of the Mining Industry Wastes as Raw Material for Melting of the Complex Fesial Ferroalloys
    Autorzy:
    Machulec, B.
    Bialik, W.
    Gil, S.
    Powiązania:
    https://bibliotekanauki.pl/articles/355998.pdf
    Data publikacji:
    2018
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    FeSiAl
    FeSi75
    model
    submerged arc furnace
    Gibbs energy minimization method
    Opis:
    An economical alternative for the steel industry which uses a separate ferrosilicon and aluminum for the deoxidization of steel is a complex deoxidizer in the form of FeSiAl alloys. The effectiveness of complex deoxidizers is higher and they have a positive effect on quality improvement and also for mechanical properties of the finished steel. It is associated with a smaller number of non-metallic inclusions and a more favorable its distribution in the structure of steel. Noteworthy are the waste from the mining industry simultaneously contains SiO2 and Al2 O3 oxides with a few of dopants in the form of CaO, MgO, FeO, TiO2 oxides. These wastes are present in large quantities and can be a cheap raw material for obtaining complex FeSiAl ferroalloys by an electrothermal method. “Poor” hard coal grades which so far did not apply as a reducing agent in the ferroalloy industry because of the high ash content can also be a raw material for the electrothermal FeSiAl process. The electrothermal FeSiAl melting process is similar to the ferrosilicon process in the submerged arc furnace. For this reason, a model based on Gibbs’ free enthalpy minimization algorithm was used to analyze the simultaneous reduction of SiO2 and Al2 O3 oxides, which was originally elaborated for the ferrosilicon smelting process. This is a system of two closed reactors: the upper one with the lower temperature and the lower one with the higher temperature. Between the reaction system and the environment, and between the reactors inside the system, there is a cyclical mass transfer in moments when the state of equilibrium is reached in the reactors. Based on the model, the basic parameters of the electrothermal reduction process of SiO2 and Al2 O3 oxides were determined and a comparative analysis was made towards the ferrosilicon process.
    Źródło:
    Archives of Metallurgy and Materials; 2018, 63, 2; 975-979
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Relation Between Active Power of the Submerged Arc Furnace and the Electric Energy Consumption Indicator in the Process of Ferrosilicon Smelting
    Autorzy:
    Machulec, B.
    Bialik, W.
    Gil, S.
    Powiązania:
    https://bibliotekanauki.pl/articles/353158.pdf
    Data publikacji:
    2019
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    ferrosilicon
    FeSi65
    FeSi75
    submerged arc furnace
    active power of furnace
    electric energy consumption
    Opis:
    Higher active power of a submerged arc furnace is commonly believed to increase its capacity in the process of ferrosilicon smelting. This is a true statement but only to a limited extent. For a given electrode diameter d, there is a certain limit value of the submerged arc furnace active power. When this value is exceeded, the furnace capacity in the process of ferrosilicon smelting does not increase but the energy loss is higher and the technical and economic indicators become worse. Maximum output regarding the reaction zone volumes is one of parameters that characterize similarities of furnaces with various geometrical parameters. It is proportional to d3 and does not depend on the furnace size. The results of statistical analysis of the ferrosilicon smelting process in the 20 MVA furnace have been presented. In addition to basic electrical parameters, such as active power and electrical load of the electrodes, factors contributing to higher resistance of the furnace bath and resulting lower reactive power Px demonstrate the most significant effect on the electrothermal process of ferrosilicon smelting. These parameters reflect metallurgical conditions of ferrosilicon smelting, such as the reducer fraction, position of the electrodes and temperature conditions of the reaction zones.
    Źródło:
    Archives of Metallurgy and Materials; 2019, 64, 2; 633-638
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Optimizing of Work Arc Furnace to Decopperisation of Flash Slag
    Autorzy:
    Bydałek, A. W.
    Biernat, S.
    Wołczyński, W.
    Bydałek, A.
    Powiązania:
    https://bibliotekanauki.pl/articles/381319.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    electrorefining
    decopperisation
    slag suspension
    arc furnace
    elektrorafinacja
    odmiedziowanie
    żużel zawiesinowy
    piec łukowy
    Opis:
    Discusses an attempt to optimize the operation of an electric furnace slag to be decopperisation suspension of the internal recycling process for the production of copper. The paper presents a new method to recover copper from metallurgical slags in arc-resistance electric furnace. It involves the use of alternating current for a first period reduction, constant or pulsed DC in the final stage of processing. Even distribution of the electric field density in the final phase of melting caused to achieve an extremely low content of metallic copper in the slag phase. They achieved by including the economic effects by reducing the time reduction.
    Źródło:
    Archives of Foundry Engineering; 2015, 15, 3; 21-24
    1897-3310
    2299-2944
    Pojawia się w:
    Archives of Foundry Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Dynamic Mode of Copper Recovery from the Post-Processing Slags
    Autorzy:
    Wołczyński, W.
    Bydałek, A. W.
    Migas, P.
    Tarasek, A.
    Najman, K.
    Powiązania:
    https://bibliotekanauki.pl/articles/352769.pdf
    Data publikacji:
    2018
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    post-processing slag
    complex reagent
    copper recovery
    arc furnace
    rotating tilted electrode
    Opis:
    The post-processing slags containing about 0.8 wt.% of copper were subjected to the treatment of a complex reagent. The chemical composition of the complex reagent has been elaborated and patented in frame of the Grant No. PBS3/A5/45/2015. The slags had an industrial origin and were delivered by the Smelter and Refinery Plant, Głogów, as a product of the direct-to-blister technology performed in the flash furnace assisted by the arc furnace. An agglomeration of copper droplets suspended in the liquid slag, their coagulation, and deposition on the bottom of furnace were observed after the treatment this post-processing slag by the mentioned reagent. The treatment of the post-processing slags by the complex reagent was performed in the arc furnace equipped with some additional electrodes situated at the furnace bottom (additional, in comparison with the arc furnace usually applied in the Smelter and Refinery Plant, Głogów). The behaviour of the copper droplets in the liquid slag within the competition between buoyancy force and gravity was studied from the viewpoint of the required deposition of coagulated copper droplets. The applied complex reagent improves sufficiently the surface free energy of the copper droplets. In the result, the mechanical equilibrium between coagulated copper droplets and surrounding liquid slag is properly modified. Eventually, sufficiently large copper droplets are subjected to a settlement on the furnace bottom according to the requirements. The agglomeration and coagulation of the copper droplets were significantly improved by an optimized tilting of the upper electrodes and even by their rotation. Moreover, the settlement was substantially facilitated and improved by the employment of both upper and lower system of electrodes with the simultaneous substitution of the variable current by the direct current.
    Źródło:
    Archives of Metallurgy and Materials; 2018, 63, 4; 1923-1930
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Determination of ZnO Amount in Electric Arc Furnace Dust and Temperature Dependence of Leaching in Ammonium Carbonate by Using of X-Ray Diffraction
    Autorzy:
    Havlik, T.
    Maruskinova, G.
    Miskufova, A.
    Powiązania:
    https://bibliotekanauki.pl/articles/350961.pdf
    Data publikacji:
    2018
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    electric arc furnace dust
    zincite
    franklinite
    recycling
    hydrometallurgy
    leaching
    kinetics
    activation energy
    XRD
    Opis:
    Zinc is present in electric arc furnace dust (EAFD) mainly in two basic minerals, namely as franklinite ZnFe2O4 and/or zincite ZnO. While zincite is relatively reactive and easily treatable, franklinite is considerably refractory, which causes problems during EAFD processing. In this work EAFD containing 18.53% Zn was leached in water solution of ammonium carbonate. This leaching solution selectively leaches zincite, while franklinite is refractory and stable against leaching in this case. The temperature dependence of zinc leaching from EAFD was studied and the activation energy EA was determined by two methods: 1.) classically based on zinc chemical analyses from the leaching solution and 2.) by using of X-Ray diffraction qualitative phase analyses of leaching residues. The determined values of activation energies 37.41 and 38.55 kJmol-1 match perfectly, which show the excellent possibility of using X-Ray diffraction toward the study of leaching kinetics at properly chosen experimental conditions. The important result is the determination of the amount zincite and franklinite in EAFD, which is not possible by using of classical chemical methods.
    Źródło:
    Archives of Metallurgy and Materials; 2018, 63, 2; 653-658
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    New directions in electric arc furnace modeling
    Autorzy:
    Grabowski, Dariusz
    Klimas, Maciej
    Powiązania:
    https://bibliotekanauki.pl/articles/2202551.pdf
    Data publikacji:
    2023
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    artificial neural networks
    chaos theory
    electric arc furnace
    fractional calculus
    power balance
    stochastic processes
    Opis:
    This paper presents new directions in the modeling of electric arc furnaces. This work is devoted to an overview of new approaches based on random differential equations, artificial neural networks, chaos theory, and fractional calculus. The foundation of proposed solutions consists of an instantaneous power balance equation related to the electric arc phenomenon. The emphasis is mostly placed on the conclusions that come from a novel interpretation of the equation coefficients.
    Źródło:
    Archives of Electrical Engineering; 2023, 72, 1; 157--172
    1427-4221
    2300-2506
    Pojawia się w:
    Archives of Electrical Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Briquetting of EAF Dust for its Utilisation in Metallurgical Processes
    Autorzy:
    Magdziarz, A.
    Kuźnia, M.
    Bembenek, M.
    Gara, P.
    Hryniewicz, M.
    Powiązania:
    https://bibliotekanauki.pl/articles/185804.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    electric arc furnace dust
    recycling
    briquetting
    zinc oxide
    elektryczny piec łukowy
    recykling
    brykietowanie
    tlenek cynku
    Opis:
    Dust generated at an electric arc furnace during steel production industry is still not a solved problem. Electric arc furnace dust (EAF) is a hazardous solid waste. Sintering of well-prepared briquetted mixtures in a shaft furnace is one of possible methods of EAFD utilisation. Simultaneously some metal oxides from exhaust gases can be separated. In this way, various metals are obtained, particularly zinc is recovered. As a result, zinc-free briquettes are received with high iron content which can be used in the steelmaking process. The purpose of the research was selecting the appropriate chemical composition of briquettes of the required strength and coke content necessary for the reduction of zinc oxide in a shaft furnace. Based on the results of the research the composition of the briquettes was selected. The best binder hydrated lime and sugar molasses and the range of proper moisture of mixture to receive briquettes of high mechanical strength were also chosen and tested. Additionally, in order to determine the thermal stability for the selected mixtures for briquetting thermal analysis was performed. A technological line of briquetting was developed to apply in a steelworks.
    Źródło:
    Chemical and Process Engineering; 2015, 36, 2; 263-271
    0208-6425
    2300-1925
    Pojawia się w:
    Chemical and Process Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Stabilization and solidification of electric arc furnace dust originating from steel industry by using low grade MgO
    Autorzy:
    Bayraktar, A. C.
    Avşar, E.
    Toröz, I.
    Alp, K.
    Hanedar, A.
    Powiązania:
    https://bibliotekanauki.pl/articles/204760.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    stabilization
    solidification
    electric arc furnace dust
    TCLP
    toxicity characteristic leaching procedure
    LG MgO
    low grade MgO
    Opis:
    In this study, solidification/stabilization (S/S) of electric arc furnace dust (EAFD) which is generated during the production of steel from scrap metals and classified as hazardous waste were investigated by using different ratios of cement and low grade MgO (LG MgO) as binding agents. Type I PC 42.5 R portland cement and LG MgO which contains 70–80% MgO were used. S/S blocks that contain different ratios of binding agents which have 1/0.5 – 1/1 – 1/2 – 1/3 – 1/4 – 1/5 cement/LG MgO ratio and S/S blocks which contain only cement and no LG MgO agents were prepared. These blocks, which contain 3 different waste ratios according to weight, 20%, 30% and 40% respectively, were produced and exposed to 28-day water purification. At the end of the purification process, S/S blocks were extracted using TCLP (Toxicity Characteristic Leaching Procedure) tests in order to determine the leaching behavior of Zn, Pb, and Cd in S/S blocks. By the end of this study, it was concluded that the recovery of EAFD is possible and applicable by immobilization. The findings of the study concluded that environmental performances or structural properties of blocks contain 30% waste by weight are suitable. This method is a proper one for recovering and treatment of EAFD with mixture of cement and LG MgO.
    Źródło:
    Archives of Environmental Protection; 2015, 41, 4; 62-66
    2083-4772
    2083-4810
    Pojawia się w:
    Archives of Environmental Protection
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Influence of High-Temperature Treatment of Melt on the Composition and Structure of Aluminum Alloy
    Autorzy:
    Grachev, V. A.
    Turakhodjaev, N. D.
    Powiązania:
    https://bibliotekanauki.pl/articles/382645.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    innovative foundry technology
    innovative foundry material
    heat treatment
    aluminum alloy structure
    fine-grained microstructure
    gasfired arc furnace
    electric arc furnace
    innowacyjna technologia odlewnicza
    innowacyjny materiał odlewniczy
    obróbka cieplna
    stop aluminium
    mikrostruktura drobnoziarnista
    piec łukowy elektryczny
    piec łukowy gazowy
    Opis:
    The aim of the current study was to examine the structure of an alloy treated at various temperatures up to 2,000–2,100 °C. Among research techniques for studying alloy structure there were the electron and optical microstructure, X-ray structure, and spectral analysis, and for studying the developed furnace geometric parameters the authors employed mathematical modeling method. The research was performed using aluminum smelting gas-fired furnaces and electric arc furnaces. The objects of the study were aluminum alloys of the brand AK7p and AK6, as well as hydrogen and aluminum oxide in the melt. For determining the hydrogen content in the aluminum alloy, the vacuum extraction method was selected. Authors have established that treatment of molten aluminum alloy in contact with carbon melt at high temperatures of 2,000–2,100 °C has resulted in facilitating reduction of hydrogen and aluminum oxide content in the melt by 40-43% and 50-58%, respectively, which is important because hydrogen and aluminum oxide adversely affect the structure and properties of the alloy. Such treatment contributes to the formation of the extremely fine-grained microstructure of aluminum alloy.
    Źródło:
    Archives of Foundry Engineering; 2017, 17, 4; 61-66
    1897-3310
    2299-2944
    Pojawia się w:
    Archives of Foundry Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Effects of steel - applied for large-dimension castings for the power engineering - refining in the ladle-furnace
    Efekty rafinacji w pieco-kadzi stali stosowanej na wielkogabarytowe odlewy dla energetyki
    Autorzy:
    Kalandyk, B.
    Wojtal, W
    Powiązania:
    https://bibliotekanauki.pl/articles/355926.pdf
    Data publikacji:
    2013
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    cast steel for power industry
    melting technology
    electric arc furnace
    ladle furnace
    desulphurisation
    staliwa dla energetyki
    technologia topienia
    elektryczny piec łukowy
    piecokadź
    odsiarczanie
    Opis:
    The changes of a sulphur content during refining in melting low-alloy and high-alloy steels (G17CrMoV5-10; GX12CrMoNiVNbN9-1) applied for large-dimension castings for the power engineering are presented in the hereby paper. The investigated steel was melted in the oxygen-recovery melting technology with an application of maximum 70% of the process scrap. In addition, after steel melting in the electric arc furnace (EAF), the secondary metallurgy was performed in the ladle furnace (LF). It was shown that the application of the secondary metallurgy by a synthetic slag in the ladle furnace and argon bubbling of a metal bath leads to obtaining in the final analysis: 0.0043-0.0046% of sulphur (a decrease of S content during refining in LF reached 40%). Current measurements of FeO in the slag and maintaining its content below 0.8%, support obtaining such low sulphur content in steel. So low level of the slag oxidizing is one of the necessary conditions for a deep desulphurisation of the metal bath. Without the secondary metallurgy the sulphur content in low-alloy cast steel was 0.007%, while 0.01% in high-alloy cast steel. Controlling of the gas (oxygen, nitrogen) content during steel melting and correcting the amount of additions (e.g. deoxidants), allowed to obtain the low oxygen content (below 45 ppm for two investigated steel grades) and nitrogen content (88 ppm for low-alloy steel and 330 ppm for high-alloy steel), which warrants a good combination of strength and plastic properties.
    W pracy przedstawiono zmiany zawartosci siarki podczas rafinacji w czasie wytapiania stali nisko- i wysokostopowej (G17CrMoV5-10; GX12CrMoNiVNbN9-1) stosowanej na wielkogabarytowe odlewy dla energetyki. Badana stal wytopiono w technologii odzyskowo-tlenowej z zastosowaniem maksymalnie 70% złomu własnego. Dodatkowo, po wytopieniu stali w piecu łukowym (EAF) przeprowadzono obróbke pozapiecowa w pieco-kadzi (LF). Wykazano, ze zastosowanie obróbki pozapiecowej zuzlem syntetycznym w pieco-kadzi i argonowania kapieli metalowej prowadzi do uzyskania w analizie koncowej 0,0043-0,0046%S (zmniejszenie zawartosci S podczas rafinacji w LF siegało 40%). Uzyskaniu tak niskiej zawartosci siarki w stali sprzyja m.in. biezacy pomiar FeO w zuzlu i utrzymanie jego zawartosci ponizej 0,8%. Tak niski poziom stopnia utlenienia zuzla jest jednym z warunków koniecznym do dobrego odsiarczenia kapieli metalowej. Bez obróbki pozapiecowej zawartosc siarki w staliwie niskostopowym wynosiła 0,007%, natomiast dla staliwa wysokostopowego 0,01%. Kontrola zawartosci gazów (tlenu i azotu) w czasie wytapiania stali i dokonywana korekta ilosci wprowadzanych dodatków (np. odtleniaczy) doprowadziła do uzyskania niskiej zawartosci tlenu (ponizej 45 ppm dla dwóch badanych gatunków stali) i azotu (88 ppm dla stali niskostopowej, 330 ppm dla stali wysokostopowej) gwarantujaca dobra kombinacje własciwosci wytrzymałosciowych i plastycznych odlewów.
    Źródło:
    Archives of Metallurgy and Materials; 2013, 58, 3; 779-783
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
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