Submit to Metals Review for Metals Propose a Special Issue

Journal Menu

Journal Browser

Advances in Molten Metal Refining Process

Print Special Issue Flyer
Special Issue Editors
Special Issue Information
Keywords
Published Papers

A special issue of Metals (ISSN 2075-4701). This special issue belongs to the section "Metal Casting, Forming and Heat Treatment".

Deadline for manuscript submissions: closed (31 August 2023) | Viewed by 14195

Share This Special Issue

Special Issue Editor

Dr. Fang Wang

E-Mail Website
Guest Editor

School of Metallurgy, Northeastern University, Shenyang 110819, China
Interests: numerical modelling; non-metallic inclusion; remelting electroslag; physical modelling; solidification
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Molten metal is the intermediate product in metallurgical processes. As our civilization grows and technological development is connected with more demanding processes, it is necessary to continuously improve the refining processes to meet customer requirements and lower production costs to stay competitive. Molten metal refining technology is governed by certain laws, the optimization of which is a basic prerequisite for increasing refining efficiency. Even in the classical metallurgy of iron and steel refining, constant innovative tendencies can be observed leading to the production of a higher-quality metal. Traditional models describing refining metallurgical processes range from turbulent flow to multiphase flow models, including heat transfer. However, at the heart of these processes, very complex multiphase and multiphysics processes, including complex chemistry, often spanning multiple time and length scales, take place. In addition, numerous works have also been developed on both experimental and analytical/computer modeling aimed at disclosing the fundamental aspects of refining metallurgical processes within molten metal. Therefore, this Special Issue is intended to collect and present the latest developments in advanced refining technologies for metallurgical processes, as well as to identify any research gaps.

The aim of this Special Issue on “Advances in Molten Metal Refining Processes” is to present current knowledge and trends in the field of molten metal refining processes, especially iron, steel, and aluminum, magnesium, titanium, the possibility of secondary processing of these metals in a liquid state by blowing inert gases, vacuuming, synthetic slag, etc., including physical and numerical modeling of these processes.

Dr. Fang Wang
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Metals is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

Refining process
Non-metallic inclusion
Micro cleanliness
Numerical modeling
Physical modeling
Process simulation
Multiscale experiments for refining

Published Papers (11 papers)

Download All Papers

Order results

Result details

Show export options Show export options

Select all

Export citation of selected articles as:

Editorial

Jump to: Research

4 pages, 172 KiB

Open AccessEditorial

Advances in Molten Metal Refining Process

by Fang Wang

Metals 2023, 13(12), 1977; https://doi.org/10.3390/met13121977 - 05 Dec 2023

Viewed by 639

Abstract

Molten metal is the intermediate product in metallurgical processes [...] Full article

(This article belongs to the Special Issue Advances in Molten Metal Refining Process)

Research

Jump to: Editorial

12 pages, 7020 KiB

Open AccessArticle

Investigation on the Alloy Mixing and Inclusion Removement through Using a New Slot-Porous Matched Tuyeres

by Xianglong Li, Huihua Wang, Jun Tian, Deyong Wang, Tianpeng Qu, Dong Hou, Shaoyan Hu and Guangjun Wu

Metals 2023, 13(4), 667; https://doi.org/10.3390/met13040667 - 28 Mar 2023

Viewed by 887

Abstract

A mathematical model was developed to investigate the refining process through using slot-porous matched dual tuyeres. In this model, the bubble expansion is considered through the ideal gas state equation. The density variation of bubbles is calculated through the mass conservation equation. The coalescence and breakup of bubbles are tracked using the discrete particle model (DPM). The transient flow is computed through the k-ε model with three continuous phases (air–slag–steel). Comparisons were made between traditional porous–porous and the new slot–porous tuyeres, mainly focusing on the mixing behavior and inclusion removement ratio. The results show that, for traditional porous–porous matched tuyeres (P-P mode), the inclusion removement ratio is 34.14%; by comparison, after employing the slot–porous matched tuyeres (S-P mode), the inclusion removements ratio rises to 36.34%. The mixing time is also shortened by 18.74% by using the S-P mode. The reason for this phenomenon is because the slot tuyere produces a strong asymmetry that drives more liquid at the bottom of the ladle. The new tuyere match takes advantage of porous and slot tuyeres, and the mixing behavior and inclusion removements are improved. The result is beneficial for future refining. Full article

(This article belongs to the Special Issue Advances in Molten Metal Refining Process)

► Show Figures

Figure 1

16 pages, 6023 KiB

Open AccessArticle

Numerical Simulation of Bubble Size Distribution in Single Snorkel Furnace (SSF) with Population Balance Model (PBM)

by Fengsheng Qi, Nan Ye, Zhongqiu Liu, Sherman C. P. Cheung and Baokuan Li

Metals 2023, 13(2), 212; https://doi.org/10.3390/met13020212 - 21 Jan 2023

Viewed by 1173

Abstract

Single Snorkel Furnace (SSF) vacuum refining furnace is a novel external refining equipment for high clean steel production. RH is a molten steel refining technology developed by Rheinstahl-Heraeus company. Compared with the traditional RH furnace, the SSF furnace has the advantages of a simple structure, high refining efficiency, and low production cost. However, because the upward flow and the downward flow are in a single snorkel, the flow phenomenon is more complex than that in the RH device. Therefore, the gas–liquid two-phase flow law in SSF furnaces plays an important role in improving equipment efficiency and accurate control. In addition, the evolution and movement behavior of bubbles have an important influence on the two-phase flow. In this study, the Population Balance Model (PBM) model is employed to study the bubble properties, taking into account the effect of bubble coalescence and breakup on the flow field. The simulation results with this model are consistent with the experimental values, and the comparison with the results of the model without the PBM is revealed to be closer with less error. The results show that with the PBM model the flow field is more homogeneously distributed, the flow velocity is more stable, and the area distribution of the upward flow and downward flow in the snorkel is more symmetrical. In the case of this study, as the fluid level rises, the bubble diameter will increase due to the decrease in hydrostatic pressure. Full article

(This article belongs to the Special Issue Advances in Molten Metal Refining Process)

► Show Figures

Figure 1

20 pages, 7377 KiB

Open AccessArticle

Numerical Simulation of Multi-Physics Fields in Fused Magnesia Furnace

by Tianchi Jiang and Weijun Zhang

Metals 2023, 13(1), 39; https://doi.org/10.3390/met13010039 - 23 Dec 2022

Cited by 1 | Viewed by 1520

Abstract

In this paper, a 3D transient multi-physical field model is developed to capture the complex processes inside a fused magnesia furnace. The multi-physics model integrates electromagnetism, thermodynamics, decomposition reactions, and flow. The three-phase submerged magnesia furnace includes an arc, magnesite ores, a melting pool, and a solidification ingot. For a more comprehensive analysis of the optimal design of industrial operations, the influence of the key index of electrode insertion depth on temperature and reaction is also discussed. The results show that the current density in the fused magnesia furnace is almost the same as the joule heat distribution, and there is an obvious area of low energy density affected by the skin effect, which leads to the waste of electric energy. The temperature at the center of the arc reaches 12,000 K, and the plasma areas formed at the end of the three electrodes are connected to each other to form a closed current path, which provides energy for the process of melting magnesia. The arc region is an ellipsoid with a length of ~30 mm and a diameter of ~49 mm. The decomposition reaction of magnesite mainly occurs in the arc area, and the radiation heat provided by the high-temperature arc is used as the heat source. There is almost no magnesite in the molten pool, and the molten pool only provides energy for the melting process of magnesia. When the electrode insertion depth is 0.4, 0.5, 0.6, and 0.7 m, the arc length is 0.049 m, 0.066 m, 0.068 m, and 0.059 m, respectively. According to the simulation results, there is an optimal electrode insertion depth. Full article

(This article belongs to the Special Issue Advances in Molten Metal Refining Process)

► Show Figures

Figure 1

11 pages, 2863 KiB

Open AccessFeature PaperArticle

Micro-Scale Flow Excitation under Imposition of Uniform Magnetic Field and Electrical Current

by Guangye Xu and Kazuhiko Iwai

Metals 2022, 12(12), 2034; https://doi.org/10.3390/met12122034 - 26 Nov 2022

Viewed by 738

Abstract

Mass transfer is often the rate-determining step for solid-liquid chemical reactions. Decreasing the concentration boundary layer thickness is essential to intensify the chemical reaction. Because the concentration boundary layer exists in the velocity boundary layer, forcing imposition on the concentration boundary layer by superimposing an electrical current and a magnetic field was proposed. Through this, flow can be directly excited in the concentration boundary layer. The previous results indicate that by superimposing a direct current and a gradient magnetic field, the development of the concentration boundary layer was suppressed because of a macro-scale flow excitation in the whole vessel. By superimposing the gradient magnetic field with a modulated current, the development of the concentration boundary layer was further suppressed. This is because of the macro-scale flow enhancement and the excitation of a micro-scale flow near the solid-liquid interface. However, the mechanism of the micro-scale flow excitation has not been clarified. To clarify this, a uniform magnetic field was superimposed with the direct current or the modulated current. By this means, only the micro-scale flow was excited near the anode surface. The results found that the non-uniform electromagnetic force distribution is the main reason for the micro-scale flow excitation. Full article

(This article belongs to the Special Issue Advances in Molten Metal Refining Process)

► Show Figures

Figure 1

13 pages, 2584 KiB

Open AccessArticle

Impact of Rotor Design on Its Wear and Work Efficiency of the Aluminum Refining Process

by Tomáš Prášil, Ladislav Socha, Karel Gryc, Jana Svizelová, Mariola Saternus, Tomasz Merder, Jacek Pieprzyca and Martin Gráf

Metals 2022, 12(11), 1803; https://doi.org/10.3390/met12111803 - 24 Oct 2022

Cited by 2 | Viewed by 1166

Abstract

Both the wear and the geometry of the rotor determine the efficiency of the process of aluminum refining. The paper presents wear tests of two different rotors: I (pump type) and II (propeller type). The operation of both rotors in industrial conditions was compared and their service life was examined. It was found that rotor I is more durable than the tested rotor II, and at the same time it provides a good level of hydrogen removal throughout the operation period, i.e., 1112 refining cycles. Rotor wear after refining was calculated by 3D scanning. The study also investigated the impact of rotor geometry on the efficiency of the refining process. The degassing efficiency was determined during refining in a foundry using the Dichte Index (DI). The alloy density and the volume of hydrogen removed were also tested for five stages of rotor wear: 0%, 25%, 50%, 75% and 100%. Both new rotors performed worse in removing hydrogen from the liquid alloy than the worn rotors due to their humidity which cannot be eliminated in the initial stage of their operation. A Dross Test was also performed to determine non-metallic impurities and compare size and number of cavities for rotor I and II. The best results of removing non-metallic inclusions by flotation were obtained for rotor I at the end of its operation. Full article

(This article belongs to the Special Issue Advances in Molten Metal Refining Process)

► Show Figures

Figure 1

11 pages, 7204 KiB

Open AccessArticle

Hydraulic Jump Behavior during Filling Process of Cast Start II

by Jin Chen, Lei Zhang, Pan Cui, Jiageng Zhang, Guowei Luan and Fei Wang

Metals 2022, 12(10), 1703; https://doi.org/10.3390/met12101703 - 12 Oct 2022

Viewed by 1078

Abstract

This paper presents a 0.25-scale quasi-three-dimensional hydraulic model experiment of transient fluid flow phenomena during continuous casting of steel under solidification. Water cooling is performed at the bottom of the mold, and saturated sodium acetate solution is covered on the spring and particle arrangement at the bottom of the mold/on the dummy bar to simulate the solidification phenomenon in the actual continuous casting process. The results show that the solidification on the dummy bar surface is very important to the early stage of the filling process and cannot be ignored. Its influence gradually decreases with the rise of the liquid level, and basically disappears when the liquid level rises to a certain height (steady liquid level, SLL). In SLL, the interface morphology of the solidified layer is more affected by the flow, while the interface morphology of the solidified layer has no significant effect on the liquid surface velocity. Full article

(This article belongs to the Special Issue Advances in Molten Metal Refining Process)

► Show Figures

Figure 1

15 pages, 4007 KiB

Open AccessArticle

Bending Force of Hot Rolled Strip Based on Improved Whale Optimization Algorithm and Twinning Support Vector Machine

by Chunyang Shi, Baoshuai Wang, Jin Chen, Ruxin Zhong, Shiyu Guo, Peng Sun and Zhicai Ma

Metals 2022, 12(10), 1589; https://doi.org/10.3390/met12101589 - 24 Sep 2022

Cited by 3 | Viewed by 1178

Abstract

Bending control is one of the main methods of shape control for the hot rolled plate. However, the existing bending force setting models based on traditional mathematical methods are complex and have low control accuracy, which leads to poor strip exit shapes. Aiming at the problem of complex bending force setting of the traditional algorithm, an improved whale swarm optimization algorithm and twin support vector machine-based bending force model for hot rolled strip steel (LWOA-TSVR) is proposed. Based on the hot rolling field production data of a steel plant, the research group established the bending force prediction model by using the nonlinear approximation ability of the twin support vector machine. The introduction of the Levy flight improvement algorithm improves the generalization ability, prediction accuracy, and convergence speed of the whale swarm optimization algorithm with the help of the convergence of coefficient vectors, solves the problem of a random selection of the parameters of the traditional whale swarm optimization algorithm and optimizes the ability of the whale swarm algorithm to jump out of the local optimum. Based on the actual rolling database, the hit rate of the proposed method reaches 91% (from −5 to 5 KN), which fully meets the requirements of the detection accuracy on the actual production line. The model is not only able to overcome the local search to obtain the global optimal solution, but also has the advantages of fast convergence and higher prediction accuracy. A comparison of the model with twin support vector machines and traditional whale swarm algorithms shows that the prediction accuracy is higher. The experimental results also show that this model has advantages over existing bending force prediction models in terms of improving the accuracy of the strip shape control and providing theoretical guidance for practical bending force settings. Full article

(This article belongs to the Special Issue Advances in Molten Metal Refining Process)

► Show Figures

Figure 1

14 pages, 16294 KiB

Open AccessFeature PaperArticle

Hydraulic Jump Behavior during Filling Process of Cast Start I

by Jin Chen, Lei Zhang, Jiageng Zhang, Pan Cui, Guowei Luan and Fei Wang

Metals 2022, 12(9), 1489; https://doi.org/10.3390/met12091489 - 08 Sep 2022

Viewed by 1214

Abstract

This paper presents a 0.25 scale quasi-three-dimensional hydraulic model experiment of transient fluid flow phenomena during continuous casting of steel. The relationship between the continuous casting process and the hydraulic jump phenomenon is established. The casting process in the mold is divided into four stages (I–IV) from the beginning to the end of continuous casting. The filling process involves stages I–II and is investigated by high-speed camera. The filling process is part of the cast start. In this paper, the hydraulic jump behavior varies and is controlled by different spring and iron chips arrangement on the dummy bar during the filling process. A filling coefficient is proposed to judge the best filling conditions and apply them to the whole filling process. There is an optimal spring and iron chip arrangement, which can adjust the hydraulic jump to optimize the initial flow field during the filling process, even the whole continuous casting process. Full article

(This article belongs to the Special Issue Advances in Molten Metal Refining Process)

► Show Figures

Figure 1

20 pages, 8510 KiB

Open AccessArticle

Lattice Boltzmann Method Modeling of the Evolution of Coherent Vortices and Periodic Flow in a Continuous Casting Mold

by Peng Zhao and Rongxun Piao

Metals 2022, 12(4), 572; https://doi.org/10.3390/met12040572 - 28 Mar 2022

Cited by 2 | Viewed by 1514

Abstract

Transient phenomena and vortex structures throughout the mold are simulated using a lattice Boltzmann method (LBM) coupled with large eddy simulation (LES) using a free surface model under steady operating conditions. The accuracy of the LBM-LES model has been verified by comparing the simulated velocities with published experimental values. The current work focuses on the evolution of the vortex structure in internal flow inside the submerged entry nozzle (SEN) jet flow and the turbulent flow near the wall of the mold. The results show various types of vortex structures with different directions are presented during the jet impingement, including the “ring, rib, and horseshoe”-like shaped vortices in the simulation, resulting in complex turbulent flow near the wall of the mold. Vortices structures are then identified and compared by different vorticial criteria, including vortex methods (ω), Q method, λ2 method (Lambda-2), Δ method (Delta), and Ω method (Omega). The formation, development, and dissipation of the vortex structures and their effects on turbulence are investigated. The results indicate that the turbulent flow (viscosity) can reflect changes in asymmetric vortices structures and flow patterns (via crossflow), which can reflect the periodical flow in the mold. Flow oscillation frequencies are mainly concentrated in the range of 0.3 Hz in this simulation. The oscillations are not a simple combination of frequency modes of crossflow in the mold. These new studies can elucidate the mechanism of vortex structure distributions in representative flow regions of the continuous casting mold. Full article

(This article belongs to the Special Issue Advances in Molten Metal Refining Process)

► Show Figures

Figure 1

12 pages, 2433 KiB

Open AccessArticle

Numerical Investigation on the Effects of Impeller Structures in Hot Metal Desulfurization Processes by Mechanical Stirring

by Ruizhi Wang, Shuyuan Jia and Zhu He

Metals 2022, 12(2), 229; https://doi.org/10.3390/met12020229 - 26 Jan 2022

Cited by 4 | Viewed by 1870

Abstract

With the increasing demand for high-quality steel, the requirements for the efficiency and stability of deep desulfurization are increasing too. The Kanbara Reactor (KR) is widely accepted around the world because of its high efficiency and economy. In order to destroy the rigid motion of molten iron in this area, two kinds of blade structures are designed and compared with traditional blades. In this study, a three-dimensional transient coupling mathematical model was established by using volume of fluid (VOF) and discrete phase model (DPM) to simulate the KR desulfurization process. The turbulence intensity of the molten iron, main vortex size and desulfurizing agent (DA) particle distributions for the three impeller models were investigated in detail. Model results showed that the staggered blade structure may improve the desulfurization efficiency of the KR process, and the desulfurization rate increases from 95.7% to 97.1% when compared with ordinary blades. The main reason for this can be attributed to the enhanced turbulence intensity of the molten iron, larger main vortex size and more uniform DA particle distributions. Plant tests also showed that the desulfurizer consumption per 1 ppm sulfur for the staggered blades was reduced by approximately 8.6%. Full article

(This article belongs to the Special Issue Advances in Molten Metal Refining Process)

► Show Figures

Journal Menu

Journal Browser

Advances in Molten Metal Refining Process

Share This Special Issue

Special Issue Editor

Special Issue Information

Keywords

Published Papers (11 papers)

Editorial

Research

Further Information

Guidelines

MDPI Initiatives

Follow MDPI