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Aluminum parts are used in the aviation industry because of the need for light. However, in addition to lightness, critical parts that must have high strength properties have also been developed. The corrosion resistance, resistance to high temperatures, and workability were investigated in this case. It becomes difficult to choose among many aluminum materials that can be alternatives to each other when these features are included. The developed approach, which considers many of the features listed above and ultimately recommends to the user the most suitable aluminum material for the relevant critical part, will be used in overcoming the difficulties in this process. A material selection model is proposed in this paper for this purpose, and the decision-making model is demonstrated with examples from the aviation industry. Therefore, the developed model, which will enable the selection of the most suitable materials among alternative materials, especially for critical parts in the aviation industry, will guide professionals working in this field. For this purpose, the fuzzy TOPSIS method is used in the study, and suitable alternatives are determined. Finally, a robustness analysis is proposed to determine the most suitable aluminum material for highly uncertain situations. We apply a stability evaluation study based on process control theory in the robustness analysis. [ABSTRACT FROM AUTHOR]

Managing industrial waste is a global challenge. Red mud is a byproduct of the aluminum industry posing serious concerns. The presence of FeO and CaO in red mud makes it a potential DeP flux. Red mud has been utilized as a DeP flux in previous studies, but these studies deal with low Si content and no P2O5 content in the red mud. However, certain steel makers have high initial Si content (0.6–0.7 wt%) in the hot metal, and with increasing demand for low P steel, new dephosphorization fluxes need to be explored. Addressing this gap, this study investigates red mud's potential as a flux for dephosphorization in hot metal with elevated Si levels. Conducting slag–metal equilibrium experiments at 1350 °C, using red mud‐based fluxes, the research achieves a 40% dephosphorization degree under optimized conditions of double deslagging and fluxing. Analysis via wet chemical methods and inductively coupled plasma mass spectrometry confirms the effectiveness of the approach. Furthermore, thermodynamic calculations highlight the influence of O2 partial pressure and Si content on dephosphorization efficacy. Through laboratory experiments and theoretical insights, this study provides a valuable roadmap for leveraging red mud as a sustainable flux in hot metal dephosphorization processes, contributing to both waste management and steel production efficiency. [ABSTRACT FROM AUTHOR]

Constructing isolated industrial microgrids with wind power is beneficial for improving the economic benefits of high-energy-consuming production, such as the electrolytic aluminum industry. Due to the specialized structure of industrial microgrids and the unique characteristics of the electrolytic aluminum load (EAL), the common emergency frequency control methods do not apply to the specific operational requirements of isolated industrial microgrids. Since EALs have huge regulating capacities and fast responses, this paper proposes a coordinated emergency frequency control scheme to deal with power disturbances in isolated industrial microgrids. The coordinated frequency control model of an industrial microgrid considering demand-side participation is derived. With the help of output regulation theory, a practical, feasible coordinated frequency controller is designed by introducing frequency deviation and power disturbance as feedback control signals. The proposed control scheme achieves reserve power distribution between the generation and demand sides. The microgrid frequency can be maintained within a permitted range in the presence of large power imbalances. The simulation results conducted in an actual isolated industrial microgrid validate the effectiveness and dynamic performance of the proposed control scheme. [ABSTRACT FROM AUTHOR]

In the current work, aluminum dross from the aluminum industry and fired-clay brick waste (Homra) were combined with alkaline activators (Na2SiO3/NaOH) with varying molarities of NaOH to create insulating geopolymer bricks. An alkaline activator with an (S/L) ratio of 3/1 was combined with Homra to replace it partly. The mixture was then molded into 50 × 50 × 50 mm3 stainless steel molds. Water absorption, compressive strength, bulk density, and apparent porosity of the produced geopolymer were measured at various curing durations and NaOH molarities. The findings showed that adding more aluminum dross waste replacement leads to a decrease in bulk density and compressive strength and an increase in the creation of pores that improve the produced bricks' ability to insulate against heat. Using 8 M of NaOH after 28 days, the findings revealed that 3% aluminum dross waste replacement has a compressive strength of about 8.6 MPa, water absorption of 14.6%, bulk density of 1.307 g/cm3, and thermal conductivity of 0.32 W/m·K. The Egyptian standard, ASTM C62, satisfies these outcomes. Using DesignBuilder energy simulation software version 6.1.06, the constructed insulating brick under ideal circumstances was utilized to calculate its contribution performance in energy consumption. The annual energy consumption was reduced by about 21% compared to traditional hollow cement bricks. [ABSTRACT FROM AUTHOR]

As the second largest solid waste in aluminum industry after red mud, the spent cathode carbon block has significant potential pollution hazards to the ecological environment, and is rich in a large number of high-quality graphite resources, with recycling properties. In order to realize the efficient recycling of high-quality graphite resources of spent cathode carbon block, the spent cathode carbon block was treated by high pressure leaching. The differences of physical and chemical properties of spent cathode carbon block, calcined petroleum coke and recovered graphite at different stages were systematically compared, and the recovered graphite was selected and blended with calcined petroleum coke to prepare the aluminum electrolytic carbon anode. The results show that compared with the calcined petroleum coke, the recovered graphite has similar industrial composition, phase composition and element content, but there are significant differences in crystal structure and asphalt wettability. In view of this, the performance of prepared anodes drops gradually with the increase of the amount of recycled graphite. Under the condition of low content, the recycled graphite from spent cathode carbon blocks has the feasibility and application potential of mixing and preparing aluminum electrolytic carbon anode. [ABSTRACT FROM AUTHOR]

The improvement and utilization of high iron and high sulfur bauxite is of great significance for ensuring the safety of strategic mineral resources in China's aluminum industry. A potential pH diagram of Fe-S-H2O system was plotted for a high iron and high sulfur diaspore bauxite with mass fraction of 13.66% iron and 16.24% sulfur, mainly consisting of pyrite. The results show that synchronous leaching of iron and sulfur can be achieved when the pH value of the system is less than the critical pH value of Fe3+ hydrolysis. Under the conditions of a liquid-solid ratio of 4 mL/g, leaching temperature of 170 °C, oxygen partial pressure of 0.20 MPa, and insulation time of two hours, the leaching rate of iron and sulfur is 94.08% and 98.34%, respectively, and the iron and sulfur mass fration in the leaching residue is 1.23% and 0.41%, respectively. The XRD results show that the main phase of the leaching residue is diaspore, achieving the improvement of high iron and high sulfur bauxite. The main solute of the leaching solution is iron sulfate, which has the potential for further resource utilization of iron and sulfur. [ABSTRACT FROM AUTHOR]

This paper examines the relationship between primary aluminum production and workplace safety, with a focus on accident rates per megawatt-hour (MWh) in the aluminum industry. As global aluminum production expands, it not only introduces economic and environmental challenges but also raises significant safety concerns inherent to heavy industry operations. Given the complexity of aluminum manufacturing and its associated risks, this study conducts a comprehensive safety analysis. Utilizing various cointegration techniques, including the Autoregressive Distributed Lag (ARDL) model, Fully Modified Ordinary Least Squares (FMOLS), Dynamic Ordinary Least Squares (DOLS), Cointegrated Regression (CCR), and the Engle-Granger and Phillips-Ouliaris tests, the research investigates the long-term relationship between production levels and accident rates. The findings reveal a significant cointegration between the variables, with the ARDL model estimating that a 1% increase in global aluminum production is associated with a 0.843% decrease in total accident rates. These results highlight the potential to enhance workplace safety through process optimization, providing valuable insights for industry stakeholders and policymakers focused on reducing risks in aluminum production. [ABSTRACT FROM AUTHOR]

The aluminum industry generates a significant amount of red mud as solid waste. This waste is high in mineral content, particularly metal oxides, and difficult to treat, manage, and recycle, resulting in malignant environmental effects. A simple, scalable, and precisely controlled hydrochloric acid treatment transforms the red mud into a useful product by selectively removing electrochemically inactive phases. This process produces a highly porous material with a significantly increased surface area, which effectively serves as the cathode material in an aqueous zinc ion battery (AZIB). RM‐HCl, which was treated with acid, had better electrochemical performance than plain red mud (RM). It had an initial specific discharge capacity of 105 mAh g−1 at 0.2 to 1.8 voltage and a current density of 100 mA g−1, which stayed at 63 % after 250 cycles. It also showed long‐term cyclic stability at high currents of 500 mAg−1 and 1000 mAg−1 for 1000 cycles. The properties of a cathode material made from RM have the potential to be a cost‐effective and environmentally friendly option. This study proposes a practical, sustainable, and expandable technique for recycling RM that promotes eco‐friendly and sustainable growth in the aluminum industry. [ABSTRACT FROM AUTHOR]

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The perfluorocarbons tetrafluoromethane (CF4, PFC-14) and hexafluoroethane (C2F6, PFC-116) are potent greenhouse gases with near-permanent atmospheric lifetimes relative to human timescales and global warming potentials thousands of times that of CO2. Using long-term atmospheric observations from a Chinese network and an inverse modeling approach (top--down method), we determined that CF4 emissions in China increased from 4.7 (4.2-5.0, 68% uncertainty interval) Gg y-1 in 2012 to 8.3 (7.7-8.9) Gg y-1 in 2021, and C2F6 emissions in China increased from 0.74 (0.66-0.80) Gg y-1 in 2011 to 1.32 (1.24-1.40) Gg y-1 in 2021, both increasing by approximately 78%. Combined emissions of CF4 and C2F6 in China reached 78 Mt CO2-eq in 2021. The absolute increase in emissions of each substance in China between 2011-2012 and 2017-2020 was similar to (for CF4), or greater than (for C2F6), the respective absolute increase in global emissions over the same period. Substantial CF4 and C2F6 emissions were identified in the less-populated western regions of China, probably due to emissions from the expanding aluminum industry in these resource-intensive regions. It is likely that the aluminum industry dominates CF4 emissions in China, while the aluminum and semiconductor industries both contribute to C2F6 emissions. Based on atmospheric observations, this study validates the emission magnitudes reported in national bottom--up inventories and provides insights into detailed spatial distributions and emission sources beyond what is reported in national bottom--up inventories. [ABSTRACT FROM AUTHOR]

We face significant environmental pollution problems due to various industries, such as the aluminum industry, which generates large amounts of red mud (RM) waste, or agriculture, in which case the use of pesticides creates huge water pollution problems. In this context, the present study offers a better perspective to originally solve both environmental issues. Thus, the main target of the study referred to using RM waste as a filler for preparing composite copolymer beads. Thereafter, this can achieve significant removal of water pollutants due to their adsorption/oxidation characteristics. As evidenced by the changes in chemical structure and composition, thermal stability, morphology, and porosity, RM was homogenously incorporated in poly(acrylonitrile-co-acrylic acid) beads prepared by wet phase inversion. The final assessment for the removal of pesticides by adsorption and oxidation processes was proven successful. In this regard, 2,4-dichlorophenoxyacetic acid was chosen as a model pollutant, for which an adsorption capacity of 16.08 mg/g composite beads was achieved. [ABSTRACT FROM AUTHOR]

Recent findings in occupational medicine have demonstrated that common pathology is one of the main factors determining poor health of workers in hazardous industries. Non-occupational pathology also has a significant effect on timing of occupational disease onset. Our objective was to conduct a comparative analysis of comorbidities in patients with different occupational diseases. The study was conducted retrospectively. We created a database of medical records of aluminum and refractory workers and analyzed all diagnoses and systemic disorders identified during the clinical examination of these patients using SPSS Statistics 23. The comorbidity index was used to determine the degree of somatic burden of the subjects. We assessed transnosological and transsystemic multimorbidity, as well as the relationship between multimorbidity and the diagnosed occupational disease. The hypothesis for normality of the indicators under study was tested by carrying out calculations using the Kolmogorov–Smirnov test, which allowed the use of parametric sample estimates, Student's t-test and one-way analysis of variance for data analysis. We established comorbidities that were significantly more frequent among the patients suffering from fluorosis or silicosis. Exposure to occupational hazards in different industries affects the profile of comorbidity. We observed a pronounced polysystemic nature of lesions in aluminum production workers and the predominance of comorbid diseases of the respiratory system in refractory workers. The level of multimorbidity among the workers of the refractory industry was significantly lower than that in the aluminum production, which allows a conclusion on a more pronounced negative impact of a combination of hazards in the latter on workers’ health.

Aluminum is an important metal material in people's modern life, and bauxite is the main raw material for the production of aluminum. With the continuous development of domestic aluminum industry, the demand for bauxite resources is increasing year by year. However, the quality of domestic bauxite resources is poor, the supply is insufficient, and the degree of external dependence of bauxite is high, which brings a serious threat to the supply security of aluminum resources in China and restricts the sustainable development of China's aluminum industry. In order to cope with the scarcity of high-quality bauxite resources in China, the development of complex and difficult-to-process bauxite resources, such as high sulfur and high iron bauxite, is crucial to ensuring the strategic security of China's bauxite resources. China has a large amount of complex bauxite resources, such as high-sulfur and high-iron bauxite, which is more than 1.5 billion tons, accompanied by other strategic metal resources, which is urgently needed to be efficiently developed and advanced technology is used to realize the industrial application of this kind of typical poor and miscellaneous bauxite. Excessive sulfur and iron impurities in bauxite will have non-negligible effects on the process of aluminum extraction by Bayer process, such as corroding equipment and pipes, increasing alkali consumption and red mud, affecting the quality of alumina and so on. Therefore, starting with the present situation and characteristics of high-sulfur and high-iron bauxite resources in China, the current research progress of desulphurization and iron removal process of high-sulfur and high-iron bauxite has been summarized. The main desulfurization technologies such as flotation desulfurization, perorating desulfurization, biological desulfurization and physical iron removal, chemical iron removal and biological iron removal are summarized. The industrial application level of various processes is discussed and several typical examples of industrial application of high-sulfur and high-iron bauxite are given. It will provide theoretical support for the development and utilization of complex bauxite resources in China, make effective use of difficult-to-process aluminum resources, reduce China's dependence on foreign aluminum resources, and improve the supporting force of bauxite resources. [ABSTRACT FROM AUTHOR]

To enhance the slagging efficiency of the lime-based slag system during the pre-treatment stage of hot metal, a composite calcium ferrite flux based on aluminum industry solid waste was developed in this study. The melting characteristics of the flux and its application in the pre-treatment of hot metal were investigated. The results indicated that the main phases of the composite calcium ferrite were CaFe2O4, Ca2Fe2O5, and Ca2(Fe,Al)2O4. It exhibited high oxidation, high alkalinity, and a low melting point, thereby achieving excellent melting performance. Simulations of various dephosphorization fluxes in the pre-treatment of high-phosphorus hot metal, ordinary hot metal, and kilogram-scale dephosphorization experiment processes were conducted. Under the same experimental conditions, the composite calcium ferrite flux was able to achieve a dephosphorization rate of over 90% and a final phosphorus content of less than 0.02 wt% under high carbon content ([%C] = 3.2 wt%). In the application of hot metal pre-dephosphorization, this flux was able to achieve efficient melting and rapid slagging of lime at a lower temperature, and its slagging time was 50% faster than that of calcium ferrite flux. In addition, this flux enhanced the utilization efficiency of lime during the steelmaking process, effectively prevented the agglomeration of slag, and achieved efficient slag–metal separation. These characteristics were significantly better than the application effect of calcium ferrite flux. This flux has significant implications for the industrial application of deep dephosphorization in the pre-treatment stage of hot metal or the early stage of converter steelmaking. [ABSTRACT FROM AUTHOR]

To realize the high‐efficiency utilization of iron‐rich coal, it is necessary to conduct in‐depth research on the ash fusion characteristics and regulation mechanism. In this paper, the ash fusion temperature test of iron‐rich coal in Xinjiang (ZC) under different atmospheres was first carried out. Then, red mud (HJ) from Huajin Aluminum Industry and black water pipe scale (GDG) were selected as the additives. After the same ashing procedure, the two additives were mixed with iron‐rich coal ash in different proportions to realize the regulation of the chemical composition of the coal ash to improve the ash fusion characteristic. The ash fusion temperature (AFT) experiment was carried out in the automatic ash melting point analyzer, and high‐temperature ash melting slags at different temperatures were prepared. The mineral phases of coal ash and slag were characterized by XRD and compared with the Factsage simulation calculation results to reveal the influence mechanism of coal ash fusion temperature. The result shows that the fusion temperature of ZC iron‐rich coal ash is significantly different between oxidizing atmosphere and weak reducing atmosphere. Compared with the oxidizing atmosphere, the four characteristic temperatures of ZC iron‐rich coal ash are significantly lower under weak reducing conditions, and the difference is about 150°C. The addition of red mud and pipeline scale increased the fusion temperature of ZC coal ash to varying degrees. The addition of HJ ash has little effect on the deformation temperature of ZC coal ash, while the addition of different proportions of HJ ash significantly increases the flow temperature of ZC coal ash. When the addition ratio of HJ ash is 40%, the flow temperature FT of ZC coal ash increases most obviously, which is about 50°C. The addition of HJ ash and GDG ash will lead to an increase in the content of iron‐containing spinel, thereby increasing the ash flow temperature. [ABSTRACT FROM AUTHOR]