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19 pages, 4516 KiB

Open AccessArticle

Characterisation of a Real-World Søderberg Electrode

by Ralph Ivor Glastonbury, Johan Paul Beukes, Pieter Gideon van Zyl, Merete Tangstad, Eli Ringdalen, Douglas Dall, Joalet Dalene Steenkamp and Masana Mushwana

Metals 2021, 11(1), 5; https://doi.org/10.3390/met11010005 - 22 Dec 2020

Cited by 3 | Viewed by 4557

Abstract

Very little research on Søderberg electrodes has been published in the journal peer reviewed public domain. The main aim of this work is to characterise a Søderberg electrode that was cut off approximately 0.5 m below the contacts shoes of a submerged arc [...] Read more.

Very little research on Søderberg electrodes has been published in the journal peer reviewed public domain. The main aim of this work is to characterise a Søderberg electrode that was cut off approximately 0.5 m below the contacts shoes of a submerged arc furnace. Additionally, the characterisation data can be used to verify if Søderberg electrode models accurately predict important electrode characteristics. The operational history (slipping, current, and paste levels) proved that the case study electrode was a representative specimen. The characterisation results indicated no significant electrical resistivity, degree of graphitisation (DOG), and bulk density changes from 0.7 to 2.7 m on the non-delta side (outward facing), while these characteristics changed relatively significantly on the delta side (inward facing) of the electrode. The area where the submerged arc would mostly like jump off the electrode had the lowest resistivity, as well as highest DOG and bulk density. No significant difference in porosity as a function of length below the contact shoes were observed; however, slight increases occurred near the perimeters. It was postulated that oxidation of carbon resulted in increased pore volumes near the electrode perimeter. No significant difference in compressive breaking strength was observed over the electrode area investigated. Full article

(This article belongs to the Special Issue Advances in Pyrometallurgy)

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13 pages, 4400 KiB

Open AccessArticle

Effect of B₂O₃ on the Sintering Process of Vanadium–Titanium Magnet Concentrates and Hematite

by Hao Liu, Ke Zhang, Yuelin Qin, Henrik Saxén, Weiqiang Liu and Xiaoyan Xiang

Metals 2020, 10(9), 1224; https://doi.org/10.3390/met10091224 - 11 Sep 2020

Cited by 3 | Viewed by 2987

Abstract

This work studied the effect of B₂O₃ (analytical reagent) on the parameters of a sintering pot test, as well as the metallurgical properties and microstructure of the sinter samples, to determine the feasibility of applying solid waste containing B₂ [...] Read more.

This work studied the effect of B₂O₃ (analytical reagent) on the parameters of a sintering pot test, as well as the metallurgical properties and microstructure of the sinter samples, to determine the feasibility of applying solid waste containing B₂O₃ in vanadium–titanium sintering. The results show that along with B₂O₃ addition, the mechanical strength of the sinter first increases and then decreases; the maximum strength was found upon the addition of 3.0% of B₂O₃. The low-temperature reduction and pulverization rate of the vanadium–titanium sinter were also improved, while the start and end temperatures of softening showed a decreasing trend. The microstructure of the sinter was found to change from plate structure to particle and point structure, with uniformly distributed small areas. The sintering pots created by B₂O₃ addition had low total porosity but a greater pore diameter than pots created without the reagent. Full article

(This article belongs to the Special Issue Advances in Pyrometallurgy)

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13 pages, 4574 KiB

Open AccessArticle

Distribution Behavior of Phosphorus in 2CaO·SiO₂-3CaO·P₂O₅ Solid Solution Phase and Liquid Slag Phase

by Bin Zhu, Mingmei Zhu, Jie Luo, Xiaofei Dou, Yu Wang, Haijun Jiang and Bing Xie

Metals 2020, 10(8), 1103; https://doi.org/10.3390/met10081103 - 17 Aug 2020

Cited by 4 | Viewed by 2903

Abstract

In this paper, the CaO-SiO₂-Fe_tO-P₂O₅ dephosphorization slag system during the premier and middle stage of the converter process was studied, the effect of slag composition on the distribution ratio and activity coefficient of P in the [...] Read more.

In this paper, the CaO-SiO₂-Fe_tO-P₂O₅ dephosphorization slag system during the premier and middle stage of the converter process was studied, the effect of slag composition on the distribution ratio and activity coefficient of P in the n·2CaO·SiO₂-3CaO·P₂O₅ (recorded as nC₂S-C₃P) solid solution phase and liquid slag phase in the slag system was studied used by the high temperature experiment in laboratory, the theoretical calculation of thermodynamics, and the scanning electron microscope and the energy dispersive spectrometer (recorded as SEM/EDS). The research results show that when the FeO content in the liquid slag increases from 32.21% to 50.31%, the distribution ratio of phosphorus (recorded as L_P) in the liquid slag phase increases by 3.34 times. When the binary basicity in the liquid slag increases from 1.08 to 1.64, the L_P in the liquid slag phase decreases by 94.21%. In the initial slag, when the binary basicity increases from 2.0 to 3.5, the L_P decreases by 70.07%. When FeO content increases from 38.00% to 51.92%, the L_P increases by 6.15 times. When P₂O₅ content increases from 3.00% to 9.00%, the L_P increased by 10.67 times. When the FeO content in the liquid slag increases from 32.21% to 50.31%, the activity coefficient of P₂O₅ in the liquid slag phase (recorded as

γ_{P_{2} O_{5} (L)}

) increases by 54.33 times. When the binary basicity in the liquid slag increases from 1.08 to 1.64,

γ_{P_{2} O_{5} (L)}

decreases by 99.38%. When the binary basicity increases from 2.0 to 3.5, the activity coefficient of P₂O₅ in the solid solution phase (recorded as

γ_{P_{2} O_{5} (SS)}

) in the solid solution phase decreases by 98.85%. When P₂O₅ content increases from 3.00% to 9.00%,

γ_{P_{2} O_{5} (SS)}

increases by 1.14 times. When the binary basicity decreases from 3.5 to 2.0, n decreases from 0.438 to 0.404. When the FeO content increases from 38.00% to 51.92%, n decreases from 0.477 to 0.319. When the P₂O₅ content increases from 3.00% to 9.00%, n decreases from 0.432 to 0.164. The decrease of binary basicity and the increase of FeO and P₂O₅ content in the initial slag can reduce the value of n and enrich more phosphorus in the solid solution phase. The results can not only provide a theoretical basis for industrial production, but also lay a theoretical foundation for finding more effective dephosphorization methods. Full article

(This article belongs to the Special Issue Advances in Pyrometallurgy)

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21 pages, 5723 KiB

Open AccessFeature PaperArticle

Experimental Model Study of Liquid–Liquid and Liquid–Gas Interfaces during Blast Furnace Hearth Drainage

by Weiqiang Liu, Lei Shao and Henrik Saxén

Metals 2020, 10(4), 496; https://doi.org/10.3390/met10040496 - 9 Apr 2020

Cited by 9 | Viewed by 3252

Abstract

The smooth drainage of produced iron and slag is a prerequisite for stable and efficient blast furnace operation. For this it is essential to understand the drainage behavior and the evolution of the liquid levels in the hearth. A two-dimensional Hele–Shaw model was [...] Read more.

The smooth drainage of produced iron and slag is a prerequisite for stable and efficient blast furnace operation. For this it is essential to understand the drainage behavior and the evolution of the liquid levels in the hearth. A two-dimensional Hele–Shaw model was used to study the liquid–liquid and liquid–gas interfaces experimentally and to clarify the effect of the initial amount of iron and slag, slag viscosity, and blast pressure on the drainage behavior. In accordance with the findings of other investigators, the gas breakthrough time increased and residual ratios for both liquids decreased with an increase of the initial levels of iron and slag, a decrease in blast pressure, and an increase in slag viscosity. The conditions under which the slag–iron interface in the end state was at the taphole and not below it were finally studied and reported. Full article

(This article belongs to the Special Issue Advances in Pyrometallurgy)

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10 pages, 2367 KiB

Open AccessArticle

Mechanism of Melt Separation in Preparation of Low-Oxygen High Titanium Ferroalloy Prepared by Multistage and Deep Reduction

by Chu Cheng, Zhihe Dou and Tingan Zhang

Metals 2020, 10(3), 309; https://doi.org/10.3390/met10030309 - 27 Feb 2020

Cited by 9 | Viewed by 2734

Abstract

A novel method to prepare low-oxygen and high-titanium ferroalloy by multistage and deep reduction was proposed in this study. Specifically, the raw materials, high titanium slag and iron concentrate are firstly reduced by insufficient Al powder to obtain high temperature melt. Secondly, CaO [...] Read more.

A novel method to prepare low-oxygen and high-titanium ferroalloy by multistage and deep reduction was proposed in this study. Specifically, the raw materials, high titanium slag and iron concentrate are firstly reduced by insufficient Al powder to obtain high temperature melt. Secondly, CaO and CaF₂ are added into the melt to adjust the basicity of the molten slag. Then, a melt separation under the heat preservation is carried out to intensify the slag-metal separation. Finally, calcium or magnesium is added into the metal melt for a deep reduction. Thereafter, high titanium ferroalloy with an extra-low oxygen content can be obtained. Effects of slag basicity and melt separation time on the slag-metal separation removal were systematically studied. The results indicate that the high titanium ferroalloy, produced by the thermite method, contains a lot of Al₂O₃ inclusions. This leads to a high oxygen and aluminum content in the alloy. With a melt separation with high basicity slag treatment, the Al₂O₃ inclusions can be effectively removed from the alloy melt, and the slag-metal separation efficiency is greatly improved. With the addition of high basicity slag during melt separation, Ti content in the alloy is improved from 51.04% to 68.24%. Furthermore, and the Al and O contents are reduced from 10.38% and 9.36% to 4.24% and 1.56%, respectively. However, suboxides, such as Ti₂O and Fe_0.9536O, still exist after a melt separation. This indicates that a deep reduction is needed to obtain extra-low oxygen high titanium ferroalloy. Full article

(This article belongs to the Special Issue Advances in Pyrometallurgy)

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14 pages, 66156 KiB

Open AccessArticle

Self-Reduction Behavior of Bio-Coal Containing Iron Ore Composites

by Asmaa A. El-Tawil, Hesham M. Ahmed, Lena Sundqvist Ökvist and Bo Björkman

Metals 2020, 10(1), 133; https://doi.org/10.3390/met10010133 - 16 Jan 2020

Cited by 14 | Viewed by 4321

Abstract

The utilization of CO₂ neutral carbon instead of fossil carbon is one way to mitigate CO₂ emissions in the steel industry. Using reactive reducing agent, e.g., bio-coal (pre-treated biomass) in iron ore composites for the blast furnace can also enhance the [...] Read more.

The utilization of CO₂ neutral carbon instead of fossil carbon is one way to mitigate CO₂ emissions in the steel industry. Using reactive reducing agent, e.g., bio-coal (pre-treated biomass) in iron ore composites for the blast furnace can also enhance the self-reduction. The current study aims at investigating the self-reduction behavior of bio-coal containing iron ore composites under inert conditions and simulated blast furnace thermal profile. Composites with and without 10% bio-coal and sufficient amount of coke breeze to keep the C/O molar ratio equal to one were mixed and Portland cement was used as a binder. The self-reduction of composites was investigated by thermogravimetric analyses under inert atmosphere. To explore the reduction progress in each type of composite vertical tube furnace tests were conducted in nitrogen atmosphere up to temperatures selected based on thermogravimetric results. Bio-coal properties as fixed carbon, volatile matter content and ash composition influence the reduction of iron oxide. The reduction of the bio-coal containing composites begins at about 500 °C, a lower temperature compared to that for the composite with coke as only carbon source. The hematite was successfully reduced to metallic iron at 850 °C by using bio-coal, whereas with coke as a reducing agent temperature up to 1100 °C was required. Full article

(This article belongs to the Special Issue Advances in Pyrometallurgy)

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17 pages, 7849 KiB

Open AccessArticle

Mechanism of CaF₂ under Vacuum Carbothermal Conditions for Recovering Nickel, Iron, and Magnesium from Garnierite

by Qiang Wang, Xupeng Gu, Tao Qu, Lei Shi, Mingyang Luo, Bin Yang and Yongnian Dai

Metals 2020, 10(1), 129; https://doi.org/10.3390/met10010129 - 15 Jan 2020

Cited by 5 | Viewed by 3320

Abstract

Nickel laterite ore is divided into three layers and the garnierite examined in this study belongs to the third layer. Garnierite is characterized by high magnesium and silicon contents. The main contents of garnierite are silicates, and nickel, iron, and magnesium exist in [...] Read more.

Nickel laterite ore is divided into three layers and the garnierite examined in this study belongs to the third layer. Garnierite is characterized by high magnesium and silicon contents. The main contents of garnierite are silicates, and nickel, iron, and magnesium exist in silicates in the form of lattice exchange. Silicate minerals are difficult to destroy so are suitable for smelting using high-temperature pyrometallurgy. To solve the problem of the large amounts of slag produced and the inability to recycle the magnesium in the traditional pyrometallurgical process, we propose a vacuum carbothermal reduction and magnetic separation process to recover nickel, iron, and magnesium from garnierite, and the behavior of the additive CaF₂ in the reduction process was investigated. Experiments were conducted under pressures ranging from 10 to 50 Pa with different proportions of CaF₂ at different temperatures. The experimental data were obtained by various methods, such as thermogravimetry, differential scanning calorimetry, scanning electron microscopy, energy dispersive spectrometry, X-ray diffraction, and inductively coupled plasma atomic emission spectroscopy. The analysis results indicate that CaF₂ directly reacted with Mg₂SiO₄, MgSiO₃, Ni₂SiO₄, and Fe₂SiO₄, which were isolated from the bearing minerals, to produce low-melting-point compounds (FeF₂, MgF₂, NiF₂, etc.) at 1315 and 1400 K. This promoted the conversion of the raw materials from a solid–solid reaction to a liquid–liquid reaction, accelerating the mass transfer and the heat transfer of Fe–Ni particles, and formed Si–Ni–Fe alloy particles with diameters of approximately of 20 mm. The smelting materials appeared stratified, hindering the reduction of magnesium. The results of the experiments indicate that at 1723 K, the molar ratio of ore/C was 1:1.2, the addition of CaF₂ was 3%, the recovery of Fe and Ni reached 82.97% and 98.21% in the vacuum carbothermal reduction–magnetic separation process, respectively, and the enrichment ratios of Fe and Ni were maximized, reaching 3.18 and 9.35, respectively. Full article

(This article belongs to the Special Issue Advances in Pyrometallurgy)

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11 pages, 6642 KiB

Open AccessArticle

Production of Ferronickel Concentrate from Low-Grade Nickel Laterite Ore by Non-Melting Reduction Magnetic Separation Process

by Guorui Qu, Shiwei Zhou, Huiyao Wang, Bo Li and Yonggang Wei

Metals 2019, 9(12), 1340; https://doi.org/10.3390/met9121340 - 12 Dec 2019

Cited by 9 | Viewed by 3953

Abstract

The production of ferronickel concentrate from low-grade nickel laterite ore containing 1.31% nickel (Ni) was studied by the non-melting reduction magnetic separation process. The sodium chloride was used as additive and coal as a reductant. The effects of roasting temperature, roasting duration, reductant [...] Read more.

The production of ferronickel concentrate from low-grade nickel laterite ore containing 1.31% nickel (Ni) was studied by the non-melting reduction magnetic separation process. The sodium chloride was used as additive and coal as a reductant. The effects of roasting temperature, roasting duration, reductant dosage, additive dosage, and grinding time on the grade and recovery were investigated. The optimal reduction conditions are a roasting temperature of 1250 °C, roasting duration of 80 min, reductant dosage of 10%, additive dosage of 5%, and a grinding time of 12 min. The grades of nickel and iron are improved from 2.13% and 51.12% to 8.15% and 64.28%, and the recovery of nickel is improved from 75.40% to 97.76%. The research results show that the additive in favor of the phase changes from lizardite phase to forsterite phase. The additive promotes agglomeration and separation of nickel and iron. Full article

(This article belongs to the Special Issue Advances in Pyrometallurgy)

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12 pages, 6297 KiB

Open AccessArticle

Metallothermic Al-Sc Co-Reduction by Vacuum Induction Melting Using Ca

by Frederic Brinkmann, Carolin Mazurek and Bernd Friedrich

Metals 2019, 9(11), 1223; https://doi.org/10.3390/met9111223 - 14 Nov 2019

Cited by 5 | Viewed by 3597

Abstract

Due to its enhancing properties in high-tech material applications, the rare earth element Scandium (Sc) is continuously gaining interest from researchers and material developers. The aim of this research is to establish an energy and resource efficient process scheme for an in situ [...] Read more.

Due to its enhancing properties in high-tech material applications, the rare earth element Scandium (Sc) is continuously gaining interest from researchers and material developers. The aim of this research is to establish an energy and resource efficient process scheme for an in situ extraction of Al-Sc master alloys, which offers usable products for the metallurgical industry. An AlSc20 alloy is targeted with an oxyfluoridic slag as a usable by-product. The thermochemical baseline is presented by modelling using the software tool FactSage; the experimental metal extraction is conducted in a vacuum induction furnace with various parameters, whereas kinetic aspects are investigated by thermogravimetric analysis. The Sc-containing products are analyzed by ICP-OES/IC concerning their chemical composition. Optimum parameters are derived from a statistical evaluation of the Sc content in the obtained slag phase. The material obtained was high in Ta due to the crucible material and remarkably low in Al and F; a comparison between the modelled and the obtained phases indicates kinetic effects inhibiting the accomplishment of equilibrium conditions. The formation of a Sc-rich Al-Sc phase (32.5 wt.-% Sc) is detected by SEM-EDS analysis of the metal phase. An in situ extraction of Al from Ca with subsequent metallothermic reduction of ScF

_{3}

as a process controlling mechanism is presumed. Full article

(This article belongs to the Special Issue Advances in Pyrometallurgy)

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12 pages, 2757 KiB

Open AccessArticle

Spectral Characterization of Copper and Iron Sulfide Combustion: A Multivariate Data Analysis Approach for Mineral Identification on the Blend

by Walter Díaz, Carlos Toro, Eduardo Balladares, Victor Parra, Pablo Coelho, Gonzalo Reyes and Roberto Parra

Metals 2019, 9(9), 1017; https://doi.org/10.3390/met9091017 - 19 Sep 2019

Cited by 11 | Viewed by 4532

Abstract

The pyrometallurgical processes for primary copper production have only off-line and time-demanding analytical techniques to characterize the in and out streams of the smelting and converting steps. Since these processes are highly exothermic, relevant process information could potentially be obtained from the visible [...] Read more.

The pyrometallurgical processes for primary copper production have only off-line and time-demanding analytical techniques to characterize the in and out streams of the smelting and converting steps. Since these processes are highly exothermic, relevant process information could potentially be obtained from the visible and near-infrared radiation emitted to the environment. In this work, we apply spectral sensing and multivariate data analysis methodologies to identify and classify copper and iron sulfide minerals present in the blend from spectra measured during their combustion in a laboratory drop-tube setup, in which chemical reactions that take place in flash smelting furnaces can be reproduced. Controlled combustion experiments were conducted with two industrial concentrates and with high-grade mineral species as well, with a focus on pyrite and chalcopyrite. Exploratory analysis by means of Principal Component Analysis (PCA) applied on the spectral data depicted high correlation features among species with similar elemental compositions. Classification algorithms were tested on the spectral data, and a classification accuracy of 95.3% with a support vector machine (SVM) algorithm with a Gaussian kernel was achieved. The results obtained by the described procedures are shown to be very promising as a first step in the development of a predictive and analytical tool in search of fitting the current need for real-time control of pyrometallurgical processes. Full article

(This article belongs to the Special Issue Advances in Pyrometallurgy)

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13 pages, 4823 KiB

Open AccessArticle

Modification Mechanism of Spinel Inclusions in Medium Manganese Steel with Rare Earth Treatment

by Zhe Yu and Chengjun Liu

Metals 2019, 9(7), 804; https://doi.org/10.3390/met9070804 - 21 Jul 2019

Cited by 28 | Viewed by 3694

Abstract

In aluminum deoxidized medium manganese steel, spinel inclusions are easily to form during refining, and such inclusions will deteriorate the toughness of the medium manganese steel. Rare earth inclusions have a smaller hardness, and their thermal expansion coefficients are similar to that of [...] Read more.

In aluminum deoxidized medium manganese steel, spinel inclusions are easily to form during refining, and such inclusions will deteriorate the toughness of the medium manganese steel. Rare earth inclusions have a smaller hardness, and their thermal expansion coefficients are similar to that of steel. They can avoid large stress concentrations around inclusions during the heat treatment of steel, which is beneficial for improving the toughness of steel. Therefore, rare earth Ce is usually used to modify spinel inclusions in steel. In order to clarify the modification mechanism of spinel inclusions in medium manganese steel with Ce treatment, high-temperature simulation experiments were carried out. Samples were taken step by step during the experimental steel smelting process, and the inclusions in the samples were analyzed by SEM-EDS. Finally, the experimental results were discussed and analyzed in combination with thermodynamic calculations. The results show that after Ce treatment, the amount of inclusions decrease, the inclusion size is basically less than 5 μm, and the spinel inclusions are transformed into rare earth inclusions. After Ce addition, Mn and Mg in the spinel inclusions are first replaced by Ce, and the spinel structure is destroyed to form CeAlO₃. When the O content in the steel is low, S in the steel will replace the O in the inclusion, and CeAlO₃ and spinel inclusions will be transformed into Ce₂O₂S. By measuring the total oxygen content of the steel, the total Ce content required for complete modification of spinel inclusions can be obtained. Finally, the critical conditions for the formation and transformation of inclusions in the Fe-Mn-Al-Mg-Ce-O-S system at 1873K were obtained according to thermodynamic calculations. Full article

(This article belongs to the Special Issue Advances in Pyrometallurgy)

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15 pages, 13254 KiB

Open AccessArticle

Deposits in Gas-fired Rotary Kiln for Limonite Magnetization-Reduction Roasting: Characteristics and Formation Mechanism

by Xianghui Fu, Zezong Chen, Xiangyang Xu, Lihua He and Yunfeng Song

Metals 2019, 9(7), 764; https://doi.org/10.3390/met9070764 - 8 Jul 2019

Cited by 8 | Viewed by 3307

Abstract

The formation mechanism of deposits in commercial gas-fired magnetization-reduction roasting rotary kiln was studied. The deposits ring adhered on the kiln wall based on the bonding of low melting point eutectic liquid phase, and the deposit adhered on the air duct head by [...] Read more.

The formation mechanism of deposits in commercial gas-fired magnetization-reduction roasting rotary kiln was studied. The deposits ring adhered on the kiln wall based on the bonding of low melting point eutectic liquid phase, and the deposit adhered on the air duct head by impact deposition. The chemical composition and microstructure of the deposits sampled at different locations varied slightly. Besides a small amount of quartz and limonite, main phases in the deposits are fayalite, glass phase and magnetite. The formation of the deposits can be attributed to the derivation of low melting point eutectic of fine limonite and coal ash, and the solid state reaction between them. Coal ash, originated from the reduction coal, combining together with fine limonite particles, results in the accumulation of deposits on the kiln wall and air duct. Fayalite, the binder phase, was a key factor for deposit formation. The residual carbon in limonite may cause an over-reduction of limonite and produce FeO. Amid the roasting process, SiO₂, originated from limonite and coal ash, may combine with FeO and reduce the liquefaction temperature, therewith liquid phase generates at high temperature zone, which can significantly promote the growth of deposits. Full article

(This article belongs to the Special Issue Advances in Pyrometallurgy)

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10 pages, 3476 KiB

Open AccessArticle

The Effect of Titanium Carbonitride on the Viscosity of High-Titanium-Type Blast Furnace Slag

by Hongen Xie, Wenzhou Yu, Zhixiong You, Xuewei Lv and Chenguang Bai

Metals 2019, 9(4), 395; https://doi.org/10.3390/met9040395 - 30 Mar 2019

Cited by 12 | Viewed by 3548

Abstract

In this paper, the effect of titanium carbonitride (Ti(C,N)) on the viscosity of high-titanium-type blast furnace slags was investigated. The different Ti(C,N) contents were achieved by adjusting the reduction degree of TiO₂ to reflect the real characteristics of the high-titanium slag. The [...] Read more.

In this paper, the effect of titanium carbonitride (Ti(C,N)) on the viscosity of high-titanium-type blast furnace slags was investigated. The different Ti(C,N) contents were achieved by adjusting the reduction degree of TiO₂ to reflect the real characteristics of the high-titanium slag. The results show that the viscosity of the slag increased with the increasing Ti(C,N) content and decreased with the rising temperature. A deviation between the measured and the fitted viscosity appeared as the content of the Ti(C,N) was beyond 4 wt%. Furthermore, the apparent viscous flow activation energy of the slag ranged from 106.13 kJ/mol to 235.46 kJ/mol by varying the Ti(C,N) contents from 0 wt% to 4.97 wt%, which was evidently different from the results of previous studies. The optical microscope and energy dispersive X-ray spectroscopy (EDS) analysis show that numerous bubble cavities were embedded in the slags and the Ti(C,N) particles agglomerated in the solidified samples. This phenomenon further indicates that the high-titanium slag is a polyphase dispersion system, which consists of liquid slag, solid Ti(C,N) particles and bubbles. Full article

(This article belongs to the Special Issue Advances in Pyrometallurgy)

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