Non-ferrous Research Articles

Radiation accidents associated with violation of rules of gathering and recycling of ferrous and non-ferrous metal scrap in the Russian Federation in 2010-2023

Radiation accidents associated with violation of rules of gathering and recycling of ferrous and non-ferrous metal scrap in the Russian Federation in 2010-2023

Comparative Analysis of the Financial and Distribution Policy of the Largest Non-ferrous Metallurgy Corporations in the BRICS Space

Non-ferrous metallurgy is of crucial importance in the life of society. The industry’s products are present in household items (household appliances, plumbing, electronics, tableware), construction, automobile and machine tool construction, batteries, etc. With the existing wide range of non-ferrous metals applications, large companies, with a high degree of vertical integration and business effi ciency, have large volumes of revenue, are able to meet the needs of consumers in a wide variety of products, and also have the opportunity to fi ll the budget system of their countries and territories where they are based. The article focuses on a comparative analysis of the fi nancial results of the largest non-ferrous metallurgy corporations in the BRICS space, namely PJSC MMC Norilsk Nickel (Russia) and Vale S.A. (Brazil), which have a total revenue of about $72.4 billion by 2021. The purpose of the study is to identify the features of the fi nancial and distribution policy of the largest metallurgical corporations in the BRICS space. The results of the study for 2009–2023 showed an increase in average net profi t by 71 % (up to 5.1 billion dollars) for the Russian company and by 1 % (up to 10.4 billion dollars) for the Brazilian company. The average profit tax rate for companies decreased by 4.9 and 9 percentage points to 21.7 and 16.9 %, respectively. The increase in dividend payments amounted to 97 and 15 % to 3.2 and 5.8 billion dollars. accordingly, at the same time, the share of net profi t allocated by companies to dividends has increased: at Norilsk Nickel — by 8.4 percentage points to 62.5 %, at Vale S.A. — by 6.5 percentage points to 55.9 %. The information base of the study was the official consolidated fi nancial statements of PJSC MMC Norilsk Nickel and Vale S.A., domestic and foreign industry literature, data from information and analytical and news agencies, information on the exchange rates of Russia and Brazil.

Asymmetric risk contagion effect of the interaction between the real economy and the financial sector—an analysis based on the domestic commodity price index

As the uncertainty of the global economy intensifies, domestic real economy risks and financial risks may interact and worsen under international risk shocks. Commodity prices are an important channel for transmitting international economic and financial risks. Taking January 2007 to July 2021 as the sample period and using data from nine commodity price indices and banking, diversified finance, and insurance industry indices, this article uses rolling regression method to construct different commodity price risk and financial sector risk indicators. Combined with a vector autoregressive model, the risk contagion effect is calculated. The analysis indicates that there exist significant asymmetric risk contagion effects between various commodities (with energy and steel having the largest risk spillover effects) and there are significant net risk spillover effects on financial sectors (with insurance having the largest risk spillover effect). There are asymmetric risk contagion effects among different financial sectors, with varying degrees of risk spillover effects on commodity prices (with the banking sector having the greatest risk spillover effects on commodity prices and other financial sectors, and diversified finance having the greatest risk spillover effect on commodities). During major global financial events, the risk spillover effects of commodities and input effects increase significantly due to the intensification of the risk spillover effects of energy, steel, and nonferrous metals. The risk spillover effect between commodities and the overall risk spillover effect have significantly increased. The financial sector’s overall net risk input effect has increased, while the net risk input effect of the insurance sector has also increased. These findings are significant for improving systemic financial risk monitoring indicators and adopting accurate prevention and control measures.

Urinary metabolic alterations associated with occupational exposure to metals and polycyclic aromatic hydrocarbons based on non-target metabolomics.

Long-term occupational exposure to metals and organics have been reported to be under great health risks. However, limited data are available on the molecular mechanism between combined exposure to metals and polycyclic aromatic hydrocarbons (PAHs) and harmful health effects. In present work, non-target metabolomics study was conducted based on urine samples from nonferrous metal smelting workers (n = 207), surrounding residents (n = 180), and the control residents (n = 187) by using ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UHPLC-QTOF-MS). Differential and correlation analyses among metabolic features indicate that total 22 differential metabolites in smelting workers were associated (p < 0.05) with metal and PAH exposure. Particularly, amino acid metabolism was strongly disturbed, and other metabolic pathways, including steroid hormone biosynthesis, citrate cycle, and pantothenate and coenzyme A (CoA) biosynthesis were also perturbed. Among them, steroid hormone biosynthesis was more affected by PAH exposure than metals, especially for hydroxyphenanthrene. These altered pathways were closely associated with oxidative stress, inflammation, and energy metabolism disorder. Additionally, our results indicate that endogenous metabolism in surrounding residents were also affected by nonferrous metal smelting activities to some extent. Our work provides valuable insights into molecular mechanisms of adverse health effects probably induced by combined exposure to metals and PAHs.

Distribution and Source-specific Ecological Risk Analysis of Soil Heavy Metals in South Hunan Province

To identify the spatial distribution patterns and assess the ecological risks associated with soil heavy metal pollution in the southern region of Hunan Province, a total of 362 surface soil samples were collected from the studied area. This study employed multivariate statistics and geographic information systems （GIS） to investigate the spatial distribution pattern of soil metals （Cd, Hg, As, Pb, Zn, Ni, Mn, Tl, and Sb）. Furthermore, the pollution sources and source-specific ecological risk of heavy metals were quantified by combining the positive matrix factorization （PMF） model and the comprehensive ecological risk index model. The results suggested that the mean concentration of soil metals in the study area exceeded the mean background values. Specifically, Cd, Hg, Pb, and Sb showed significant pollution levels and substantial spatial variability, with their concentrations reaching the background values by factors of 8.31, 9.12, 5.09, and 2.79, respectively. The spatial distribution of these heavy metals exhibited discernible patterns, with a higher concentration observed in western Chenzhou and a noticeable trend of increasing concentrations from the central region towards the periphery. The clusters with high concentrations of heavy metals were predominantly situated near industrial zones engaged in black metal smelting and processing and nonferrous metal mining and processing enterprises. Source apportionment indicated that the primary sources of soil heavy metals in the area were industrial activities associated with black metal mining and metallurgy （29.06%）, atmospheric deposition （22.05%）, nonferrous metal mining and processing （20.65%）, a combination of industrial and transportation sources （14.73%）, and natural sources （13.50%）. Moreover, the source-ecological risk assessment model specifically identified Cd and Hg as crucial elements requiring prioritized control measures to mitigate soil ecological risks. Industrial activities, including black metal smelting and processing and atmospheric deposition sources, were identified as the priority sources for health risks in the study region. These results provide an important theoretical basis for the development of effective strategies aimed at managing and diminishing the risks associated with heavy metal contamination in the southern region of Hunan Province.

„Poszukuje się aryjskich zbieraczy!” – wojenny „recykling” w Generalnym Gubernatorstwie 1939–1945

„Aryan collectors are wanted!“ – Wartime „recycling“ in the General Government in 1939–1945 In the General Government, as well as in other occupied territories, the collection of raw materials for war purposes was promoted and organized in a completely different way than in the Third Reich, USA or Great Britain. In these countries, actions were created as a kind of second front in the fight against the enemy, in which housewives and chlidren who could not actively participate in the fight, could voluntarily get involved. In the General Government, however, the action was part of the occupational coercion. At the beginning of the occupation in General Goverment, the obligatory collection covered non-ferrous metals important for war production. In the following years among others: glass, paper, iron, leather and rubber were also collected. Apart from the activities of the occupier, school collections in which Polish students and teachers participated were important. In 1944 year voluntary bonus collections were also established, in which metals were exchanged for vouchers for bottles of vodka. The occupant‘s actions were accompanied by a widely developed Polish-language press campaign, which was supposed to encourage participation in the collections secondary raw materials. The article aims to describe the Nazi propaganda for Polish people and social attitudes related to the collection of recyclable materials for German war industry purposes in the General Government. This text as well to show the exceptional specificity of these actions in the said territory and is contribution to research on war recycling in Central and Eastern Europe.

Prevalence and Risk Factors of Lower Extremity Musculoskeletal Disorders Among Occupational Groups in Key Industries - China, 2018-2023.

Lower extremity musculoskeletal diseases (LE-MSDs) have emerged as a significant contributor to the global disease economic burden and worker absenteeism, becoming a global public health concern. However, the epidemic characteristics of LE-MSDs among occupational populations in China are unknown. This report finds that the LE-MSDs prevalence rate among key occupational groups in China is 17.7%, with the top 5 being toy manufacturing, medical personnel, automobile manufacturing, nonferrous metal smelting and rolling processing, and coal mining and washing. This study investigated the occurrence of LE-MSDs in key industries in China and its possible risk factors to provide big data support for preventing and controlling such diseases in these industries.

Behavior and Mechanisms of Antimony Precipitation from Wastewater by Sulfate-Reducing Bacteria Desulfovibrio desulfuricans

The development of the non-ferrous metal industry is generating increasingly large quantities of wastewater containing heavy metals (e.g., Sb). The precipitation of heavy metals by microorganisms involves complex mechanisms that require further investigation to optimize bioremediation technologies. In this study, we employed a sulfate-reducing bacteria (SRB) strain Desulfovibrio desulfuricans CSU_dl to treat the antimony (Sb)-containing wastewater; the behavior of Sb and mechanisms underlying precipitation were investigated by characterizing the precipitates. The results showed that the abiotic factors constraining SRB bacterial growth greatly affect Sb forms and precipitation. For instance, Sb precipitation maximumly occurred at pH 6 and 7, or C:N ratio of 10:1 and 40:3 for Sb(III) and Sb(V), respectively, resulting in a maximum Sb removal rate of 94%. Interestingly, we found that substantial antimonate and antimonite were adsorbed on the SRB cell surface, indicating that cell surface is a critical reaction site of Sb transformation and precipitation. Sb was adsorbed to the cell surface by C-C and C=O groups, and was further precipitated by forming Sb2S3 and Sb2S5 or was coprecipitated with the P-containing group. Partial Sb(V) reduction was also observed on the SRB cell surface. These results provided a deep insight into the Sb bio-transformation and were an advancement with respect to understanding bioremediation of Sb-contaminated wastewater.

Тұрмыстық қатты қалдықтардың сапалық және сандық құрамын зерттеу

Based on the fractional composition of municipal solid waste, it is possible to divide the objects of their collection into low-component and multi-component ones. Small-scale objects for the collection of municipal solid waste are trade and public catering enterprises. Municipal solid wastes of these facilities contain waste paper, glass, plastic, polyethylene, and non-ferrous metals. The main part of these wastes from these facilities, 75% of the volume, can be sorted and processed. This is due to the high volume and low moisture content of the waste collected at these facilities. High humidity and a large amount of composite materials of municipal solid wastes complicate sorting. The last factor presents a sorting problem. Multicomponent municipal solid waste is present at landfills mainly in the following combinations: paper-polyethylene-foil, metal-paper, metal-plastic, metal-plastic-ceramic, polyethylene- plastic, paper-polyethylene, textile-plastic, textile-plastic-rubber.

RESEARCH OF THE PROCESS OF ABSORPTION AND DISTILLATION OF SODA ASH PRODUCTION BY THE AMMONIA METHOD AS A CONTROL OBJECT

Soda soda is one of the largest volume chemical products and the most important raw material component in various industries. The volume of soda ash production significantly affects the development of a number of other industries, including the production of glass, ferrous and non-ferrous metallurgy. Not only the sphere of production, but also the sphere of consumption of soda ash is characterized by a high degree of concentration. The global consumption of soda ash in 2012 was, according to experts, 54.7 million tons / year, its growth is 1% per year. As a technological facility for the production of soda ash, it is distinguished by a complex scheme of material flows flowing mainly through column-type devices, multi-stage continuous chemical-technological processes, multidimensionality, inertia, complex dependencies between input and output parameters of technological modes, etc., i.e. it has all the characteristic features complex systems. The production of soda ash includes 8 main and 3 auxiliary departments (a department means a group of devices that are connected by the commonality of processes occurring in them due to the presence of leading flows and appropriate collectors for storing raw materials). The article analyzes the possibility and necessity of decomposition of the general task of control soda ash production into the subtask of managing absorption and distillation departments; carbonation, filtering and calcination and other production departments. Such a decomposition is technologically natural, since the absorption and distillation departments do not have headers for collecting the steam-gas mixture and makes it possible to develop and implement control systems for such departments and the production of soda ash as a whole by stages, provided that the productivity of the relevant departments is coordinated. The article also conducts a study of the absorption and distillation department as an object of control and sets the general task of control this department.

Investigating the impact of the porous structure of needle-punched preform-based carbon-carbon composites on the completeness of liquid silicon infiltration

Currently, siliconized carbon-carbon composites (C/C composites) hold a significant position among materials used in nonferrous metallurgy. The process of Liquid Silicon Infiltration (LSI) for porous C/C composites is strongly inf luenced by their microstructural characteristics. Studying the effect of the porous structure of various C/C composites on the completeness of silicon infiltration can enable the regulation of the phase composition of siliconized materials over a wide range, as well as the physical, mechanical, and thermophysical properties of C/C–SiC composites. This paper presents the results of analyzing the porous structure and strength characteristics of C/C composites based on needle-punched preforms with different types of carbon matrices (pyrocarbon, natural and synthetic pitch coke, and phenol-formaldehyde resin coke) and the C/C–SiC composites derived from them. Due to the specific features of carbon matrix formation from liquid or gas phases, differences in pore size distribution were observed. A carbon matrix formed by the gas-phase method exhibits fewer nanoscale pores compared to one formed by the liquid-phase method. The inf luence of the pore structure and the nature of the matrix carbon in various needle-punched preforms on the degree of saturation during LSI, infiltration depth, and mechanical properties was determined.

On the prospects of identifying rare and rare earth metals in the black shale sequence of the Eastern segment of the Greater Caucasus

The expansion, updating, and comprehensive utilization of the mineral resource base for rare and rare-earth metals necessitate the search for and development of new deposits of non-traditional genetic types, including those localized within black shale formations. This study examines the distribution of rare and rare-earth elements (REE) in the black shale formation of the Eastern segment of the Greater Caucasus, where extensive research and exploratory drilling have led to the discovery of several deposits and occurrences of non-ferrous metals. The results of geochemical and mineralogical investigations reveal a high concentration of rare and rare-earth elements (REE) and other metals within the black shale formation. All lithological types of rocks constituting the black shale formation, as well as rocks from the near-deformation and hydrothermally metasomatized zones, were tested for this study. Comparative studies of the behavior of rare and rare-earth elements across various rock types indicated significant variations in their elemental spectrum and concentrations. Notably, elevated concentrations of rare-earth elements were observed in clay-rich rocks, attributed to the sorptive capacity of clay minerals. Analysis of the distribution of microelements in the rocks and main minerals of the black shale formation highlighted a considerable presence of rare, rare-earth, and other elements, with concentrations exceeding their Clarke values by several times. Distinct anomalous zones were identified for Au, Mo, Cs, La, Ce, Nd, Sm, and U, while anomalous zones were noted for Cd, Se, Hf, Yb, Lu, Eu, Tb, and Th. The geochemical characteristics related to the concentration of these elements were also determined. The findings indicate that the unique properties of graphitized clay shales and accessory minerals within the formation significantly influence the processes of concentration of rare and rare-earth elements, serving as sources of associated metals. This study further analyzes the geochemical and mineralogical characteristics of the black shale formation and delineates zones of mobilization and concentration for rare, rare-earth, and other elements.

Thermodynamic Analysis and Optimization of Power Cycles for Waste Heat Recovery

Improvement of energy efficiency in technological processes at industrial enterprises is one of the key areas of energy saving. Reduction of energy costs required for the production of energy-intensive products can be achieved through the utilization of waste heat produced by high-temperature thermal furnace units. Generation of electric power based on the waste heat using power cycles with working fluids that are not conventional for large power engineering, may become a promising energy saving trend. In this paper, thermodynamic analysis and optimization of power cycles for the purposes of waste heat recovery are performed. The efficiency of combining several power cycles was also evaluated. It has been established that the combination of the Brayton recompression cycle on supercritical carbon dioxide with the organic Rankine cycle using R124 allows for greater electrical power than steam-power cycles with three pressure circuits under conditions where the gas temperature is in the range of 300–550 °C and the cooling temperature of is up to 80 °C. Additionally, when cooling gases with a high sulfur and moisture content to 150 °C, the combined cycle has greater electrical power at gas temperatures of 330 °C and above. At enterprises where the coolant has a high content of sulfur compounds or moisture and deep cooling of gases will lead to condensation, for example, at petrochemical and non-ferrous metallurgy enterprises, the use of combined cycles can ensure a utilization efficiency of up to 45%.

Resistance Element Welding (REW) of Steels with Non-Ferrous Materials: Potentials, Challenges, and Properties

Performance and functionality are two key factors in designing advanced components. One promising approach in manufacturing design is the fabrication of multi-material structures by joining dissimilar materials. Steels, known for their outstanding properties and cost-effective production, are widely used across several industries. However, their high density presents challenges when designing lightweight components. A solution lies in combining steels with lightweight, non-ferrous alloys to develop cost-effective multi-material parts. However, joining different materials is generally complex due to their different properties, making it sometimes challenging or even unfeasible. Resistance element welding (REW) offers a high-performance alternative to traditional methods, such as resistance spot welding, with a high potential in mass production industries like automotive manufacturing. This article comprehensively reviews the latest research on REW for dissimilar joining of steels and non-ferrous alloys. It focuses on the microstructural and mechanical properties of joints, innovations in the REW process, the influence of process parameters on joint quality, as well as simulation and numerical studies. In addition, REW is compared with traditional joining methods.

Some aspects of the development of musculoskeletal pathology in children in an industrial center with a city-forming enterprise for the production of non-ferrous metal alloys

Introduction. At present, incidence of musculoskeletal diseases is growing in children, especially in areas with poor quality of the environment The purpose of the study was to identify markers of the development of musculoskeletal pathology in children to minimize the risk of health under conditions of exposure to emissions from a non-ferrous metal alloy production plant. Materials and methods. We performed clinical examination in four hundred ninety five 5 and 7 years children (54.3% boys and 45.7% girls). They lived in a large industrial center where safe standards for chemical in ambient air were violated per aluminum (up to 3.06 average daily MPL) and gaseous fluorides (up to 8.25 average daily MPL). Also, we examined 95 children (57.9% boys and 42.1% girls) who lived in an area where the foregoing chemicals were detected in ambient air in levels not exceeding 0.3–0.54 average daily MPL. The children were examined by pediatrician. Levels of aluminum and fluoride-ion were determined in urine. We examined phosphor-calcium metabolism indices and markers of bone tissue synthesis and resorption. The study also involved performing ultrasound densitometry. Results. The children form the observation group had aluminum and fluoride-ion levels in their urine up to 3.2 times a higher than their peers from the reference group. Likelihood of musculoskeletal pathology, including deforming dorsopathy, was found to be up to 1.3 times higher for the exposed children. Bone metabolism failure manifested itself in the exposed children through elevated levels of ionized calcium in blood; elevated levels of N-osteocalcin in 25.4% of the exposed children and elevated activity of tartrate-resistant acid phosphatase in 59.3%. Bone marrow resorption was by 9.2 times more likely to be activated in the exposed children from a large industrial center. Impaired bone tissue remodelling was accompanied with lower bone mineral density in 54.7% of the exposed children. Limitations. The study was conducted on 5–7 years children. Conclusion. Markers of bone tissue metabolism disorders can be used to implement sanitary-epidemiological and medical-preventive measures to reduce the risk of developing osteopathic conditions in childhood.

The Analysis of Volatility for Non-Ferrous Metal Futures in Chinese Market Based on Multifractal Perspective

The goal of this paper is to study the behavior of non-ferrous metal futures’ volatilities in Chinese future market by applying a multifractal perspective. In particular, in order to obtain key indicators that describe the characterization of non-ferrous metal futures’ volatility behavior, we uses noise-removed EMD-MF-DFA and original MF-DFA methods to conduct a comparative analysis on the return time series of four non-ferrous metal futures, which are Aluminum future, Copper future, Zinc future and Lead future traded on the Shanghai Futures Exchange. This numerical study shows that the indicator established in characterizing the volatility of four non-ferrous metal futures is robust. In addition, we have the following four conclusions: First, there are obvious multifractal phenomena of non-ferrous metal futures in Chinese market, and it shows that Aluminum future has the largest degree of multifractality, and Copper future has the smallest degree of multifractality, which indicates that Aluminum future has the highest volatility complexity, and Copper future has the smallest volatility complexity. Second, it is found that the volatility complexity of these four non-ferrous metal futures is caused by long-range correlation. Third, this study also supports the current judgment that “Copper future has the greatest investment opportunity”. Finally, combined with analysis results, we also give suggestions to investors, producers, and regulators body for non-ferrous metal futures market in China.

Impact of Lance Bending Failure on Bath Dynamics of Top-Submerged Smelting Furnace for Non-ferrous Metals

Impact of Lance Bending Failure on Bath Dynamics of Top-Submerged Smelting Furnace for Non-ferrous Metals

Determination of the porosity structure of acid resistants based on non-ferrous metallurgy wastes by method of mercury porometry and diffuse X-ray scattering

Determination of the porosity structure of acid resistants based on non-ferrous metallurgy wastes by method of mercury porometry and diffuse X-ray scattering

Искажение геометрии, окисление кромки, структурные изменения и морфология поверхности реза листового проката толщиной 100 мм из алюминиевых, медных и титановых сплавов при плазменной резке на токе обратной полярности

The introduction describes the feasibility of using reverse polarity plasma cutting to produce large-sized non-ferrous metal blanks up to 100 mm thick. Data on the use of plasma cutting with direct and reverse polarity currents for thick sheet metal and the main technological problems associated with its implementation are presented. The purpose of the work is to study the organization of the structure and properties of the near-surface zone, changes in the chemical and phase composition when cutting aluminum, copper and titanium alloys. The research methods are optical and scanning electron microscopy, microhardness measurement, X-ray diffraction and energy-dispersive analysis. Plasma cutting was carried out using air as a plasma-forming and shielding gas, simultaneously with water injection into the discharge chamber and the formation of a “water fog” around the plasma column. Results and discussion. It is shown that both the arc stability and the shape of the plasma column are of great importance in reverse polarity plasma cutting of rolled sheets. The distortion of the cutting geometry during normal operation is greatest in the central part, and with insufficient heat input it shifts to the lower part and increases significantly. The operation of the plasma torch in air does not lead to significant changes in the composition of the cutting surface of aluminum and copper alloys. A decrease in the magnesium content near the edge is typical for the aluminum alloy in the surface layers. Cutting of the titanium alloy is accompanied by intense oxidation of the surface, especially in areas of difficult metal displacement from the cutting cavity. The formation of titanium oxides, mainly rutile Ti2O, sharply increases the microhardness values in the surface layers, which negatively affects the machinability of the cutting edge and requires shot blasting to remove the oxide layer. The conclusion describes the main patterns of implementing reverse polarity plasma cutting of sheet metal from aluminum, copper and titanium alloys with a thickness of 100 mm.

Innovative techniques for joining and processing of some aluminum alloys used in the aircraft industry

The continuous development of various cutting-edge fields of science and technology, including the aerospace industry, is advancing at an accelerated pace. To meet current technical, economic, and environmental demands, new ecological and efficient material joining and processing techniques have been developed, aiming to replace some of the commonly used industrial procedures. For aluminum alloys, friction-based joining and processing methods with a rotating tool element are presented in this paper, with potential applications in the aerospace industry. Data is provided on Friction Stir Welding (FSW), known for its ability to produce high-quality joints without compromising the structural integrity of materials, highlighting its advantages over traditional welding methods. The diversity of metallic materials, their characteristics and properties, as well as the technical requirements of different applications, have led to the development of variants of the friction stir welding process, one of which is Submerged (underwater) Friction Stir Welding (SFSW). Data on FSW and SFSW welding as well as several aluminum alloys that can be used in the aerospace industry are included in the paper. The paper also discusses ISIM's approaches in the FSW/SFSW domain for aluminum alloys EN AW 6082 and EN AW 7075 that are applicable to the aerospace industry because of their relevance and interest. The positive outcomes show that FSW and SFSW welding can be developed for a variety of metallic materials. The goal of ISIM’s current and future research is to apply the principles of the FSW/SFSW process to the FSP/SFSP processing of non-ferrous alloys, which can be used in a variety of industries.