Non-ferrous Research Articles

Valorization of Residue from Aluminum Industries: A Review

Recycling and reusing industrial waste and by-products are topics of great importance across all industries, but they hold particular significance in the metal industry. Aluminum, the most widely used non-ferrous metal globally, generates considerable waste during production, including dross, salt slag, spent carbon cathode and bauxite residue. Extensive research has been conducted to recycle and re-extract the remaining aluminum from these wastes. Given their varied environmental impacts, recycling these materials to maximize residue utilization is crucial. The components of dross, salt slag, and bauxite residue include aluminum and various oxides. Through recycling, alumina can be extracted using processes such as pyrometallurgy and hydrometallurgy, which involve leaching, iron oxide separation, and the production of alumina salt. Initially, the paper will provide a brief introduction to the generation of aluminum residues—namely, dross, salt slag, and bauxite residue—including their environmental impacts, followed by an exploration of their potential applications in sectors such as environmental management, energy, and construction materials.

The effect of complex extra-furnace treatment of metal melts on the formation of non-metallic inclusions in large-sized ingots

Abstract The article presents the results of studying non-metallic inclusions (NI) after extra-furnace treatment of the 13Cr9Mo2Co1NiVNbNB steel melt to produce large-sized ingots. The objects of the study were laboratory samples melted in a semi-industrial induction furnace with the capacity of 20 tons (the first batch), and samples obtained after melting in an electric arc furnace with the capacity of 120 tons, followed by modification and double vacuuming (the second batch).
Previously, using the Fact Sage software, modeling of the NI formation processes was carried out. The data were obtained on the possible NI composition and amount in this steel.
Studying NIs (the composition, the contamination index, inclusion parameters) was carried out on an ASPEX Explorer electron microscope using the method of automatic X-ray spectral analysis of particles (Automatic Features Analysis, AFA). It was established that in the samples of the first batch, the main part of the NIs consisted of chromium- and manganese-containing oxides: chromium-manganese spinels (Cr-Mn-O and Mn-Cr-Si-O groups), which occupy more than 94% of the total area of the NIs. In the samples of the second batch, the main part of the Nis was represented by Cr-Mn-O; Al-Cr-O; Cr-Al-Mn-O systems.
It was shown that the average size of non-ferrous substances in the samples of the laboratory batch and in industrial samples after extra-furnace treatment differs slightly (5-12%), however, the contamination index in industrial samples after vacuum treatment and especially after modification and repeated vacuum treatment was reduced by more than 10 times. The results obtained allow recommending vacuum treatment and complex modification with calcium and boron as measures to prevent the formation of non-ferrous metals and to improve metallurgical quality when smelting large ingots using complex alloy steels.

The Effect of Ash-Slag on Drying of a Ceramic Sample Based on Non-Ferrous Metallurgy Waste

The Effect of Ash-Slag on Drying of a Ceramic Sample Based on Non-Ferrous Metallurgy Waste

Application of melting technology in the treatment of nonferrous hazardous waste residues

ABSTRACT In order to find a more effective treatment method for non-ferrous hazardous waste residues, the research proposed the fusion disposal technology of collaborative resource residues. The empirical results showed that the leaching concentrations of Cr and Pb of the molten products of the resource residue were maintained at 0 mg/L, and the final leaching concentrations of most heavy metals were within 0.10 mg/L, which showed low toxicity to the environment. The above results show that the fusion disposal technology of collaborative resource residue is an effective treatment method. The fusion disposal technology not only reduces the heavy metal leaching concentration of non-ferrous metals, but also promotes the development of hazardous waste residue treatment technology.

CBS-YOLOv5: fault detection algorithm of electrolyzer plate with low-resolution infrared images based on improved YOLOv5

Abstract In the process of copper electrorefining, accurate detection of electrode plate faults is extremely challenging due to the low resolution of captured infrared images, significant noise interference, and dense electrode plate arrangements. To address these challenges, this paper proposes an improved YOLOv5-based electrode plate fault detection algorithm called CBS-YOLOv5. This algorithm introduces several innovations over the original YOLOv5, including: the incorporation of coordinate attention to enhance the ability of the feature extraction network to separate target information from noise; the construction of a small object detection module to improve the detection of dense small objects by increasing the resolution of the feature map; the replacement of the traditional path aggregation network with a Bi-directional Feature Pyramid Network (BiFPN) for more flexible multi-scale feature fusion; and the integration of the swin transformer to optimize the cross-stage partial bottleneck structure, significantly enhancing the model’s ability to detect densely packed small objects. Experimental results show that the proposed CBS-YOLOv5 model achieves an accuracy of 88.1%, which is an improvement of 5.7% over the base model. Furthermore, this algorithm demonstrates exceptional detection capabilities for dense small objects in low-resolution infrared images while maintaining real-time detection speed, making it suitable for various complex industrial scenarios, including fault detection in non-ferrous metal electrolysis processes. CBS-YOLOv5 not only improves detection accuracy and robustness but also has broad application prospects, offering a new solution for intelligent manufacturing and industrial inspection.

Kinetic features and mechanism of scorodite formation via multivalent iron source from arsenic-bearing solution

Arsenic-bearing wastes from non-ferrous metallurgy exhibit poor stability during long-term storage, and are transferred as pollutants to the atmosphere and groundwater, thereby, threatening human health and ecological security. Immobilising arsenic as scorodite crystals via a multivalent iron source (Fe(OH)3-FeSO4·7 H2O) is one effective approach for controlling arsenic pollution. However, the kinetic features and mechanisms of this method have not yet been revealed, thereby, necessitating further research. Herein, the kinetics of scorodite generation influenced by the initial pH, Fe/As ratio, Fe(III)/Fe(II) ratio, and reaction temperature were investigated. Prominent features included variations in the minimum pH, oxidation–reduction potential (ORP) platform, Fe/As ratio (1.0), and the delay or advance of scorodite generation. The complicated mechanism of scorodite formation can be divided into coordinated polymerisation, acidic Fe(OH)3 dissolution, polymer oxidation, Fe(II) oxidation, and scorodite crystallisation. The fast coordinated polymerisation of precursors ([Fe(H2O)4(H2AsO4)]nn+) in stage I resulted in a decrease in pH; Fe(OH)3@scorodite and Fe(H2O)2AsO4 basic units were formed via the oxidation of ionic Fe(III) in stage II. Furthermore, regular octahedral scorodite was generated from two sources: the crystallisation of Fe(H2O)2AsO4 basic units and Ostwald ripening of flaky scorodite from Fe(III)–As(V) precipitates at stage III. The Fe(II) in the polymers was mainly oxidised by ferric ions generated from the oxidation of ferrous ions via dissolved O2 from the oxygen gas. Fe(II) ions as carriers for transferring electrons from O2 to polymers. Scorodite formation was controlled by the oxidation of Fe(II) by oxygen gas. Overall, this study provides guidance for the effective immobilisation of arsenic wastes into scorodite via multivalent iron sources to eliminate arsenic pollution.

The Assessment of Abrasion Resistance of Casted Non-Ferrous Metals and Alloys with the Use of 3D Scanning

The Assessment of Abrasion Resistance of Casted Non-Ferrous Metals and Alloys with the Use of 3D Scanning

Classification and progress of extraction technologies for nonferrous metal resources

Classification and progress of extraction technologies for nonferrous metal resources

Pollution of Heavy Metals in Topsoil of Remote Mountainous Areas in Western Yunnan-Guizhou Plateau

Heavy metals from anthropogenic emissions have had a negative impact on the ecological environment in remote regions. A total of 69 topsoil samples were collected from 13 remote mountainous areas in the western Yunnan-Guizhou Plateau at altitudes of 2 563-4 037 m, and the concentrations of ten heavy metals in the samples were determined. Enrichment characteristics and pollution sources of heavy metals in topsoil were discussed by referencing the enrichment factor （EF）, positive matrix factorization （PMF）, and Pb isotopes. The results showed that the average concentrations of Al, Fe, Cu, V, and Zn in the topsoil were lower than the soil background values in Yunnan Province； the average concentrations of Ni and Pb were similar to the background values； and the average concentrations of Cd, Cr, and Hg were 1.8-3.6 times higher than the background values. The average EF values of Pb, Cr, and Ni were 3.8, 3.4, and 2.3, respectively, showing moderate enrichment according to the EF classification criteria； the average EF values of Cd and Hg were 15.2 and 10.0, reflecting significant enrichment； and the average EF values of the other metals ranged from 1.1 to 1.9, displaying none-weak enrichment. Combining the comparisons of heavy metal concentrations and ratios in topsoil and bedrock and the EF and PMF results, Al, Fe, V, Cr, Cu, Ni, and Zn in topsoil were considered primarily from detrital sources, and the spatial concentration variations of the metals should have been mainly regulated by the parent material. Cadmium, Hg, and Pb were obviously polluted by anthropogenic emissions, and the main sources were non-ferrous metal smelting and coal combustion. The areas with relatively high Cd, Hg, and Pb pollution were mainly distributed in the Jiaozi snow mountain, Bitahai watershed, Luoji Mountain, and Laojun Mountain areas. Anthropogenic emissions contributed 23.8% of the accumulation of heavy metals in the topsoil.

Research on Magnetic Field of Permanent Magnet Rolls Arranged Periodically in Circumferential—Axial Direction

The separation of non-magnetic non-ferrous metals such as copper and aluminum from scrapped automobiles is a critical area of research due to the increasing number of end-of-life vehicles. Traditional eddy current separation methods have limitations, particularly in handling large-sized broken copper and aluminum parts. This paper proposes a novel magnetic roller model featuring a circumferential–axial periodic arrangement of permanent magnets. This study explores the external magnetic field distribution of this new roller design by constructing an equivalent current model, solving magnetic scalar potential equations, and employing simulation tools. The findings indicate that the new magnet array enhances both the magnetic field strength and the range of the external magnetic field, leading to improved separation efficiency of large-sized metal fragments. The results provide a theoretical basis for advancing the separation technology of large-sized broken copper and aluminum parts in scrapped automobiles, offering potential improvements in the recycling of non-ferrous metals from end-of-life vehicles.

Transforming tire-derived char into powerful arsenic adsorbents by mild modification

A large amount of arsenic-containing wastewater discharged by the non-ferrous metal industry will cause serious environmental problems if it is not properly treated. Pyrolysis char of waste tire is a kind of solid waste. Since the surface properties of tire derived char (TC) are affected by tar/ash adhesion during pyrolysis, it is necessary to modify TC to treat wastewater containing As(V) effectively as an adsorbent. At present, most studies on the modification of TC are prepared into activated carbon by high temperature activation in N2 atmosphere. In this study, TC was modified at room temperature and air atmosphere, and Fe(OH)3-TCNaOH adsorbent with particle size of 61–75 μm was obtained under the premise of the removal rate of As(V) and the settling performance of the adsorbent. When the initial concentration of As(V) was 5 mg/L, the removal rate of As(V) by Fe(OH)3-TCNaOH with a particle size of 61–75 μm could reach 90% within 30 min under a wide pH range (3–9). The adsorption of As(V) by Fe(OH)3-TCNaOH was most affected by the coexistence of PO43-, which resulted in the removal rate of As(V) decreased by about 20%. The adsorption mechanism shows that the significant increase in the number of 3–5 nm mesoporous pores of Fe(OH)3-TCNaOH and the formation of H bonds are beneficial to the adsorption of Fe(OH)3-TCNaOH to As(V), and improve the stability of Fe-As complex.

Стратегические перспективы развития отрасли цветных металлов: проблемы и задачи отечественных производителей

The non-ferrous metallurgy industry in Russia is undergoing profound changes due to geopolitical shifts, the transition to green energy, and the need to develop processing industries. Non-ferrous metals, as strategically important products, can play a decisive role in achieving the global goals of the Russian economy related to economic security, the development of domestic markets, the reconstruction of high-tech industries, the modernization of stably functioning industries, and the improvement of the quality of life for the population. The purpose of this research is to study the trends and risks affecting non-ferrous metal producers and to assess the opportunities and challenges for developing both external and domestic markets, ultimately aiming to ensure sustainable demand for the products of mining companies and metal producers. The primary research methods used include general scientific approaches such as comparative analysis, synthesis, and decomposition. This paper reviews the current state of Russia's non-ferrous metallurgy sector and explores its development prospects, with a specific focus on Norilsk Nickel, a key player operating in the Arctic. The main results of the study include an assessment of the current global market for non-ferrous metals, their role in the energy transition, and the formation of a low-carbon economy. The study also analyzes and summarizes the challenges facing domestic non-ferrous metallurgy and suggests potential directions for its development in the current economic context. A critical analysis of the Strategy for the Development of the Metallurgical Industry of the Russian Federation for the Period up to 2030 reveals that several important aspects and issues are not adequately addressed in the document. For example, it lacks a strategic planning methodology and fails to consider the specific characteristics and potential of the Arctic’s non-ferrous mineral resource base. The practical significance of this study lies in clarifying the prospects for utilizing non-ferrous metals to support the revitalization of high-tech industries in the national economy.

Achieving Super-Metallophobicity on Silicon-based Ceramics at High Temperature.

As a critical concept in physical chemistry, superwettability is widely concerned in both fundamental science and practical engineering in past few decades. Despite this, investigation on high temperature superwettability is still a void, which is significant both in scientific and industrial fields. Herein, a ceramic with specific high temperature non-wetting property, Si2N2O is proposed. Compared with other materials, Si2N2O is elucidated with better practical non-wetting property against various non-ferrous metals. Combining with micro-nanostructures, the metallophobicity is further improved (contact angle >150° and contact angle hysteresis ≈0°). The extraordinary metal repellency is defined as "super-metallophobicity", which is proved to be induced by distinctive thermodynamic and dynamic wetting behavior on the rough surface. The research of super-metallophobicity not only sheds light on superwettability at high temperature, but also offers worthy insights for future potential material design in a wide range of applications, such as metallurgy, 3D printing and semiconductor industry.

Pulse-constructed energy–saving PbO2 electrode for copper electrowinning

Energy-saving PbO2 exhibit significant application potential in the non-ferrous metal electrowinning industry. By optimizing the deposition time, heteropolar spacing, nitric acid concentration, pulse current density and pulse frequency, the optimum conditions for deposition of PbO2 electrode were obtained. Meanwhile, the effects of electrodeposition parameters on the electrochemical performance, phase structure and morphology of β-PbO2 were systematically evaluated. The mechanism of action of pulse and direct current deposition was proposed. The simulated copper electrowinning experiment shows that an improved current efficiency (91.6%) was achieved and the low energy consumption (1855.1 kW⋅h/t) for copper production per ton was significantly reduced. Compared with the electrode prepared by direct current deposition, the current efficiency of copper is increased by 4.3% and the energy consumption is reduced by 198.6 kWh/t. Additionally, the PbO2 electrode produced by the optimized pulse deposition process exhibits excellent stability, which service-time is increased by approximately 99.4%. This research offers insights for developing energy-efficient and long-lived electrode materials.

Effect of Synthesis Process on ZSM-5 Morphology from Non-ferrous Metal Tailings

Effect of Synthesis Process on ZSM-5 Morphology from Non-ferrous Metal Tailings

Eudialyte of the Kola Peninsula Is a Promising Source for Obtaining Composite Zr–Ti–SiO2 Sorbents of Nonferrous Metals and Radionuclides

Eudialyte of the Kola Peninsula Is a Promising Source for Obtaining Composite Zr–Ti–SiO2 Sorbents of Nonferrous Metals and Radionuclides

STUDY OF THE BEHAVIOR OF ARSENIC IN COPPER ELECTROLYTE

Abstract. In industrial wastewater, arsenic is most often present in the trivalent state. An analysis of existing purification methods shows that in all cases, with a few exceptions, the most complete removal of arsenic is observed from solutions in which it is in the pentavalent state. This is explained by the significantly lower solubility of arsenates of heavy and alkaline earth metals compared to the corresponding arsenites. The chemical oxidation of As(III) in the following systems was studied: As(III)-H2SO4-H2O, As(III)-MeSO4-H2O, As(III)–H2SO4–MeSO4–H2O (where Me is Cu, Ni, Co, Mn, Zn). The influence of temperature, the amount of transition metal ions, the duration of the experiment, and the concentration of sulfuric acid on the degree of transition of As(III) to As(V) was studied. The effect of catalytic oxidation of As(III) in sulfuric acid solutions was discovered. The maximum degree of oxidation of trivalent arsenic (55-60%) is observed when transition metal salts are introduced into an arsenic solution in the presence of a platinum plate. It has been established that the nature of the studied transition metal salts (Cu2+, Ni2+, Co2+, Mn2+, Zn2+), process duration and temperature do not have a significant effect on the degree of As(III) conversion. The results obtained largely explain the predominance of pentavalent forms of arsenic in production solutions of non-ferrous metallurgy. Key words: copper electrolyte, arsenic, transition metals, catalytic role, instant oxidation effect, activated oxygen.

Die „Kovacs-Vase“

The Kovacs Vase was first made known under scholars in Munich in 1996, but its origins and current owner are unknown. It could be shown that the pictorial scenes come from the Greek Pankration. It has now been proposed to date the Kovacs Vase to 400 AD. The successful fight of the alround-fighter Privatulus is shown in five scenes, with legends attached to the fight pictures describing the athletes in more detail. The inscriptions also indicate that it must have been an experienced and victorious all-fighter from the Green Circus Party (factiones). What is unusual is that the loser Victorinus is also mentioned by name, possibly also a successful fighter, over whom victory may have meant an outstanding achievement for Privatulus. All additions are written in a vulgar Latin that is similar to Proto-Romance and is difficult to understand. The overview and comparison of silver and non-ferrous metal jugs and vases from the 4th to 8th centuries shows that in the toreutics of this period both traditional forms and motifs have been present since the 4th century and new forms and decorative elements appear that clearly differ from the late Roman origins. The Kovacs Vase combines ‘classic’ shapes and motifs from the 6th century with innovative elements that indicate an independent, classicist development. It could be that it was made in a workshop in northern Italy. Although written sources mention gymnastic agones, no firmly dated images from the 5th century are known to date. Against this historical-archaeological background, the Kovacs Vase with its depictions and inscriptions is a unique testimony to Greek agonistics in late antiquity.

Asymmetric impact of oil structural shocks on non-ferrous metals supply chains: A groundbreaking multidimensional quantile-on-quantile regression

This paper examines the predictability of various oil price shocks on the returns of non-ferrous metals from the supply and demand sides in the US, UK, and China under different market conditions. An innovative multidimensional quantile-on-quantile (MD-QQ) regression approach is proposed to address this topic, which extends traditional univariate QQ regression to multivariate cases, addressing the limitation of omitted variables in the benchmark QQ method. The findings reveal that the forecasting of oil supply shocks on the non-ferrous metal supply chain is generally insignificant. Nevertheless, oil supply shocks will transmit negative (positive) actions when the non-ferrous metal supply-side (demand-side) is in a bear (bull) market. The implication of oil demand shocks on the non-ferrous metal supply chain is generally positive, while the supply-side market of Chinese non-ferrous metals displays mutability in response to oil demand shocks under certain extreme market conditions. Conversely, oil risk shocks have a negative impact across the entire non-ferrous metal supply chain. Their effects are more pronounced when the non-ferrous metal demand market is bearish, exhibiting asymmetric characteristics. Oil demand shocks and risk shocks have a stronger impact on non-ferrous metal supply chains in the US and UK than in China. Our research not only confirms the estimation bias caused by missing variables in traditional baseline models but also provides new insights into the connection between the non-ferrous metals and oil markets by adopting the fresh method.

Complex Treatment of Industrial Waste Water Containing Non-Ferrous Metals

Complex Treatment of Industrial Waste Water Containing Non-Ferrous Metals