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Theoretical and experimental substantiation of obtaining an alloy from flotation tailings of lead-zinc sulfide ore

Shevko Victor M., Makhanbetova Baktygul A., Aitkulov Dosmurat K.

Physicochemical Problems of Mineral Processing

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2023

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Vol. 59, iss. 1

art. no. 161853

EN

The article presents the results of thermodynamic and experimental research on the processing of cinders from the firing of Shalkiya deposit lead-zinc ore tailings with the production of siliceous ferroalloys. Thermodynamic modeling carried out using the HSC-6.0 complex based on the Gibbs energy minimization principle showed that the interaction occur with the formation of CaSiO3, FeSiO3, MgSiO3, K2OˑSiO2, FeSi, Fe5Si3, SiC, Fe3Si, Si, SiOg, FeSi2.33, FeSi2, CaSi, Zn, Zng, Pb, Pbg; an increase in the iron amount in the system allows increasing the silicon extraction degree into the alloy at 1800°C to 76%, to reduce the silicon concentration in the alloy from 41 to 24%; FS25 grade ferrosilicon formed at 1752-1867°C in the presence of 88-100% iron, and FS45 grade ferrosilicon – at 1863-1900°C and 20-22.4% iron. Electric melting of a charge containing 63.83% calcined cinder of tailings, 19.15% coke, and 17.02% steel chips allows to obtain FS45 grade ferrosilicon (44.1-43.9% Si) with the extraction of 69.7% silicon and sublimates with the content of 32-38% zinc and lead. The results obtained allow complex processing of lead-zinc sulfide ore tailings with the extraction of not only non-ferrous metals, but also silicon in the ferroalloy.

2

Processing of phosphorites with extraction of phosphorus, obtaining calcium carbide and ferroalloy

Shevko Victor M., Uteyeva Raisa A., Badikova Alexandra D., Tleuova Saltanat T.

Physicochemical Problems of Mineral Processing

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2023

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Vol. 59, iss. 6

art. no. 174463

EN

The article considers the results of studying the thermodynamic computer modeling of the interaction of phosphorite (Karatau basin, Kazakhstan) with carbon and coke performed using the HSC-10 software package and electric smelting of the phosphorite with coke and steel shavings in an arc furnace. The modeling allowed us to determine the equilibrium extraction degrees of phosphorus into gas (Р2, Р4), silicon into ferroalloy in the form of iron silicides (FeSi2, FeSi, Fe3Si, Fe5Si3, Si) and calcium into CaС2. At temperatures above 1500 °C, regardless of the amount of iron, the extraction degree of phosphorus into gas is more 99%. The resulting ferroalloy contains 21.2-23.8% of Si, 1.6-2.8% of Al; the calcium carbide has a capacity of 288-325 dm3/kg. The extraction degree of silicon into the alloy was 89.8%, calcium in CaC2 – 72.5%, phosphorus into gas – 99.4%. The ferroalloy, formed at the electric smelting of the Chulaktau phosphorite together with coke and steel shavings and containing 24.9-29.8% of Si, is FS25 grade ferrosilicon, and the formed calcium carbide has a capacity of 278-290 dm3/kg and belongs to the third and second grades. The developed technology makes it possible to increase the degree of phosphorites’ comprehensive use two times (up to 87.5%).

3

Thermodynamic Description of Ternary Fe-B-X Systems. Part 8: Fe-B-Mo, with Extension to Quaternary Fe-B-Cr-Mo System

Miettinen Jyrki, Visuri Ville-Valtteri, Fabritius Timo

Archives of Metallurgy and Materials

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2021

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Vol. 66, iss. 1

281--295

EN

Thermodynamic optimizations of the ternary Fe-B-Mo system and its binary sub-system B-Mo are presented. The Fe-B-Mo description is then extended to the quaternary Fe-B-Cr-Mo system by assessing the ternary B-Cr-Mo system. The thermodynamic descriptions of the other binaries (Fe-B, Fe-Cr, Fe-Mo, B-Cr, and Cr-Mo) and the other ternaries (Fe-B-Cr and Fe-Cr-Mo) are taken from earlier studies. In this study, the adjustable parameters of the B-Mo, Fe-B-Mo, and B-Cr-Mo systems were optimized using the experimental thermodynamic and the phase equilibrium data from the literature. The solution phases of the system (liquid, bcc and fcc) are described with the substitutional solution model, and most borides are treated as stoichiometric phases or semistoichiometric phases, using a simple two-sublattice model for the latter. The system’s intermetallic phases, Chi, Mu, R, and Sigma (not dissolving boron) as well as boride M3B2, based on a formulation of (Cr,Fe)(Cr,Fe,Mo)2(B)2, are described with a three-sublattice model. Reasonable agreement is obtained between the calculated and measured phase equilibria in all four systems: B-Mo; Fe-B-Mo; B-Cr-Mo; and Fe-B-Cr-Mo.

4

Thermodynamic Description of Ternary Fe-B-X Systems. Part 6: Fe-B-Ti

Miettinen J., Visuri V.-V., Fabritius T., Milcheva N., Vassilev G.

Archives of Metallurgy and Materials

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2019

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Vol. 64, iss. 4

1249--1255

EN

Thermodynamic optimizations of the ternary Fe-B-Ti system and its binary sub-system, B-Ti are presented. The thermodynamic descriptions of the other binaries, Fe-Ti and Fe-B, are taken from the earlier studies slightly modifying the Fe-Ti system assessment. The adjustable parameters of the Fe-B-Ti and B-Ti systems are optimized in this study using the experimental thermodynamic and the phase equilibrium data from the literature. The solution phases of the system are described using the substitutional solution model and the compounds (including borides) are treated as stoichiometric phases. The results show a good correlation between the calculated and measured thermodynamic and phase equilibrium data.

5

Thermodynamic Description of Ternary Fe-B-X Systems. Part 5: Fe-B-Si

Miettinen J., Visuri V.-V., Fabritius T., Milcheva N., Vassilev G.

Archives of Metallurgy and Materials

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2019

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Vol. 64, iss. 4

1239--1248

EN

Thermodynamic descriptions of the ternary Fe-B-Si system and its binary sub-system, B-Si, are developed in the context of a new Fe-B-X (X = Cr, Ni, Mn, V, Si, Ti, C) database. The thermodynamic parameters of the other binary sub-systems, Fe-Si and Fe-B, are taken from earlier assessments. Experimental thermodynamic and phase equilibrium data available in the literature has been used for the optimization of the thermodynamic parameters of the Fe-B-Si and B-Si systems. The solution phases are described using substitutional solution model and the compounds (silicides and borides) are treated as stoichiometric phases. The calculated and experimental thermodynamic and phase equilibrium data were found to be in good agreement.

6

Gas fired plant modeling for monitoring and optimization of electricity and heat production

Madejski P., Żymełka P., Węzik R., Kubiczek H.

Journal of Power Technologies

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2017

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Vol. 97, nr 5

455--462

EN

There has been a marked increase in recent years in the use of gas fired systems characterized by high efficiency and the ability to quickly adapt to changing demand for electricity and heat. To optimize operations for gas fired systems in light of changing demand and changing electricity prices the production process must be planned and monitored with appropriate tools. This paper presents the concept of a tool for monitoring and optimizing heat and electricity production in a gas fired plant. The basic element of the tool is a comprehensive mathematical model of the gas fired plant, verified based on results from on-site tests. The mathematical model is used to perform calculations for defined input data of ambient conditions and heat demand, to determine current heat and electricity production. The paper presents simulation results in the form of changes in the amount of electricity and heat produced during a day, with the aim being to monitor the conditions of the plant and prepare a reliable production plan.

7

Wykorzystanie programu FactSage w projektowaniu stalowniczych żużli kadziowych

Różański P., Borecki M., Szypuła I.

Prace Instytutu Metalurgii Żelaza

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2012

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T. 64, nr 1

184-187

PL

Komputerowe programy termochemiczne wraz z bazami danych, obejmującymi ciekłe stale, żużle i stałe roztwory tlenków coraz częściej wykorzystuje się do symulacji skomplikowanych reakcji chemicznych i równowag fazowych występujących w procesach wytwarzania stali. Dzięki temu można ograniczyć zakres eksperymentów w skali laboratoryjnej i przemysłowej, co pozwala skrócić czas i obniżyć koszty prac badawczo-rozwojowych. Za pomocą programu FactSage można obliczyć lepkość żużli oraz określić przebieg ich krzepnięcia przy użyciu modelu równowagowego lub modelu Scheil'a, wyznaczając temperatury likwidusu i solidusu oraz powstające fazy. Symulacje w układzie ciekła stal-żużel pozwalają oceniać zdolności rafinacyjne żużli, w tym zdolność odsiarczania lub odfosforowania kąpieli stalowej. Z kolei symulacje w układzie żużel - materiał ogniotrwały można wykorzystać w procesie doboru wymurówki roboczej urządzenia na linii żużla. W artykule przedstawiono przykłady wykorzystania programu FactSage w procesie doboru kadziowego żużla rafinacyjnego.

EN

Computer programs with thermochemical databases, covering the liquid steels, slags and oxide solid solutions, are increasingly used to simulate complex chemical reactions and phase equilibria occurring in the steelmaking process. This enables to limit number of experiments in laboratory and industrial scale, which allows shortening the time and reducing the cost of research and development works. Slag viscosity can be calculated and slag solidification microstructure can be defined using the equilibrium solidification and Scheil's models by FactSage software. Simulations in the liquid steel - slag refining systems allow to assess the refining abilities of slags, including the desulfurization and dephosphorization ability of steel bath. The simulations in the system slag - refractory material can be used in selection of refractory materials for the slag line. The paper presents examples of thermochemical simulations made by FactSage used for selection of the ladle refining slag.

8

Zależność pomiędzy składem chemicznym popiołów a charakterystycznymi temperaturami topliwości popiołów węglowych oraz temperaturą likwidus

Jerzak W.

Karbo

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2012

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Nr 3

146--153

PL

Przedstawiono przegląd metod obliczeniowych dotyczących wyznaczenia zależności charakterystycznych temperatur topliwości od składu chemicznego popiołów węglowych. Przedmiotem badań było powiązanie obliczonych w pakiecie Fact-Sage 6.2 temperatur likwidus popiołów, w atmosferze utleniającej (powietrza) dla składów zaczerpniętych z literatury, z temperaturami kuli, półkuli i płynięcia. Obliczenia przeprowadzono w zakresie temperatur od 1250 do 1650°C z krokiem co 2°C dla 22 składów popiołów węglowych. Analizowano próbki popiołów zawierające dziewięć komponentów. Wyznaczone w FactSage 6.2 temperatury likwidus dla badanych popiołów węglowych zawierały się w przedziale 1294-1580°C. Uporządkowanie badanych popiołów według wzrastającej temperatury likwidus nie pokrywa się z kolejnością wzrostu temperatur ST, HT czy FT. Dla każdej próbki popiołu prognozowano pierwszą fazę stałą, jaka pojawiłaby się w ciekłym popiele węglowym podczas procesu ochładzania. Stosując estymację parametrów równań liniowych, uzyskano zadowalające odzwierciedlenie eksperymentów. Umiarkowaną zgodność wyników reprezentowaną przez współczynnik determinacji 0,76 odnotowano w przypadku temperatury kuli, natomiast dla temperatur płynięcia oraz półkuli współczynnik ten osiągnął satysfakcjonujący poziom (R2=0,94). Zaproponowane parametry do równań na temperatury ST, HT i FT pozwalają niejednokrotnie wierniej odzwierciedlić wyniki eksperymentów od pozostałych modeli empirycznych dla próbek popiołów spełniających kryteria do ich zastosowania. W przypadku temperatury półkuli wykazano 100 % zgodność wyników doświadczeń z obliczeniami, jeśli różnica temperatur pomiar/obliczenia nie przekracza ±40°C.

EN

A review of computational methods concerning the determination of correlations between the characteristic fusion temperatures and the chemical compositions of coal ashes has been made in the article. The purpose of the research presented in this article was to relate the liquidus temperatures of ashes, as computed in the FactSage 6.2 package in an oxidizing (air) atmosphere for compositions drawn from the literature, with the sphere, hemisphere and flow temperatures. The computations were performed in the temperature range from 1250°C to 1650°C with a step of 2°C for 22 coal ash compositions. Ash samples containing nine components were analyzed. The liquidus temperatures as determined in FactSage 6.2 for the coal ashes under study were contained in the range from 1294°C to 1580°C. The ordering of the examined ashes by increasing liquidus temperature does not coincide with the order of increase of ST, HT or FT temperatures. For each ash sample, the first solid phase that would arise in the liquid coal ash during the cooling process was predicted. By using the estimation of the linear equation parameters, the experiments were reflected satisfactorily. A moderate consistence of the results, as represented by the determination coefficient being equal to 0.76, was noted for the sphere temperature, whereas for the flow and hemisphere temperatures this coefficient attained a satisfactory level (R2=0.94). The proposed parameters for the equations for the ST, HT and FT temperatures often allow the experimental results to be reflected better than in the cases of the other empirical models for samples of ashes satisfying the criteria for their use. For the sphere temperature, a 100% consistence between the experimental results and the computations was demonstrated, if the measurement/computation temperature difference did not exceed ±40°C.

9

Obliczenia równowagowe a wyniki pomiarowe produktów spalania gazu ziemnego w atmosferze CO2/O2/N2

Jerzak W., Kalicka Z., Kawecka-Cebula E.

Archiwum Spalania

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2012

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Vol. 12, nr 3

81--90

PL

Zaprezentowano porównanie wpływu atmosfery CO2/O2/N2 i O2/N2 na stężenie wybranych produktów spalania gazu ziemnego. Obliczenia równowagowe wykonano w programie FactSage™ 6.2 [1] w warunkach adiabatycznej temperatury płomienia. Numeryczne warianty warunków spalania, jak stężenie tlenu i CO2 w mieszance paliwowej oraz współczynnik nadmiaru tlenu, odpowiadały przeprowadzonym próbom eksperymentalnym. Porównanie wyników eksperymentalnych z obliczeniami w stanie równowagi wykazało podobieństwo m. in. w kierunku spadku stężenia NO wraz ze wzrostem zawartości CO2 w mieszance paliwowej. Zwiększanie współczynnika nadmiaru powietrza w przypadku atmosfery O2/N2 powodowało, początkowo wzrost stężenia NO a następnie spadek, zarówno w przypadku obliczeń jak i pomiarów. Dodatek CO2 do mieszanki utleniającej powodował zwiększenie stężenia CO w spalinach. Efekt ten słabnął wraz ze wzrostem współczynnika nadmiaru tlenu. Przedstawiono również wyniki obliczeń wpływu składu mieszanki na równowagowe stężenia rodników, mających istotny wpływ na przebieg procesu spalania. Wykazano, iż obliczenia równowagowe mogą być pomocne do określenia kierunku zmian składu spalin, szczególnie w przypadku modyfikacji składu mieszanki paliwowej.

EN

The effect of an O2/N2/CO2 atmosphere in comparison with the O2/N2 one on the concentrations of natural gas combustion products was presented. The equilibrium calculations were performed with FactSage ™ 6.2 program [1] for the adiabatic flame temperature. The combustion conditions assumed for the performed numeric calculations, such as the oxygen and carbon dioxide concentrations in oxidizing mixture and the oxygen excess ratio in the fuel mixture, were the same as in the carried-out experiments. The comparison of the experimental results with the calculated ones done for equilibrium conditions showed that NO concentration was decreasing in flue gas with increasing CO2 concentration in fuel mixture. In O2/N2 atmosphere, the increase in oxygen excess ratio results initially in increasing NO concentration, and then in its decrease, which was indicated by the calculations as well as the experimental studies. The CO 2addition in oxidizing mixture was producing the CO increase in flue gas. The effect was declining when the oxygen excess ratio got higher. There was also presented the effect of fuel mixture composition on equilibrium radicals concentrations, which affect substantially the combustion process. It was shown that the equilibrium calculations can be of help to indicate the direction of changes of flue gas composition, especially for the case, when the fuel mixture composition is modified.

10

A phase-field model for multi-component and multi-phase systems

Moelans N.

Archives of Metallurgy and Materials

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2008

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Vol. 53, iss. 4

1149-1156

EN

An alternative phase-field model is presented for the simulation of microstructure evolution in polycrystalline materials existing of multiple phases and components. The model is able to treat concurrently phase transformations, diffusion controlled coarsening (Ostwald ripening) and grain growth. The eąuilibrium phase fractions and compositions are introduced using appropriate thermodynamic Gibbs energy expressions. Furthermore, the model allows to specify the energy and mobility, and their anisotropy, for each interface individually and the diffusion properties of the different phases. Simulation results are discussed for the coarsening of a simplified Cu/Cu-Sn solder joint with Cu6Sn5-precipitates.

PL

Przedstawiono alternatywny model pól fazowych zastosowany do symulacji zmian mikrostruktury w materiałach polikrystalicznych w układach wielofazowych i wieloskładnikowych. Zaproponowany model uwzględnia jednocześnie przemiany fazowe oraz kontrolowany dyfuzyjnie rozrost ziaren (tzw. dojrzewanie Ostwalda). Przedstawiono i przedyskutowano wyniki uproszczonej symulacji przeprowadzonej dla połączenia lutownego Cu/Cu-Sn z wydzieleniem Cu6Sn5.