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Copyright of Nonferrous Metals (Extractive Metallurgy) is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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]

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]

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.

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]

In the context of "dual carbon", the aluminum smelling industry is facing enormous pressure to reduce emissions. This paper takes an electrolytic aluminum enterprise n Shanxi province as an example to calculate the carbon emissions of each ink of the enterprise in 2021 and identify the mam factors that affect the carbon emission reduction of the electrolytic aluminum industry. Using scenario analysis method to predict the adjustment of power structure, upgrading of low-carbon electrolytic aluminum technology, and application of recycled aluminum in Shanxi province from 2021 to 2030. Establish a multi factor analysis model for electrolytic aluminum carbon emissions, and explore the impact of various control variables on reducing carbon emissions per ton of aluminum for enterprises in benchmark and policy scenarios. The results show that changes in the power structure have the greatest contribution to the greenhouse gas emissions reduction of the enterprise, with emissions reductions accounting for 31. 63% of the total emissions under the 2030 baseline scenario and 40. 66% of the total emissions under the policy scenario; When coupled with changes in power structure and the proportion of recycled aluminum, the emission reduction effect Is most significant, with the emission reduction accounting for 67.82% of the total emissions in the 2030 policy scenario; Under the three coupling situation, the carbon emissions of the enterprise gradually tend to zero. [ABSTRACT FROM AUTHOR]

The global aluminium industry faces a serious challenge in reducing greenhouse gas emissions as the demand for aluminium continues to increase. The aluminium industry has a responsibility to streamline its energy consumption, especially in the production process. There have been many studies discussing energy consumption performance in the industry. However, most of them only discuss energy saving partially, without involving energy consumption with various items produced. This paper proposes an energy savings measurement in the manufacturing industry. An energy baseline consumed per unit volume has been developed using the equivalent volume method with an energy management control system (EMCS). The study takes a case example from the automotive--aluminium component industry. The steps taken in the study are: examining the production process, converting the production volume to equivalent, calculating the energy consumption ratio, developing an energy baseline, simulating the savings performance, and then proposing an EMCS with key performance indicators (KPI) for sustainability. The results show that the development of a baseline using the ratio of energy and an equivalent volume of production gives a better data correlation with an R² value close to one. From the baseline, the bestdemonstrated performance (BDP) can be used as a reference to set energy goals. Furthermore, the data and the deviant deleted have the same baseline value. They differ in energy reduction goal percentages. The practical application of this study is not only in the manufacturing industry but in other industries as well, such as building management. This study contributes to energy savings achieved with EMCS. [ABSTRACT FROM AUTHOR]

Implementing green production management (GPM) practices has become increasingly vital for ensuring a sustainable future. Integrating green scientific research into the aluminum industry is imperative for achieving economic and environmental benefits. Despite being touted as a "green metal," the aluminum production process presents significant sustainability challenges. Notably, the industry contributes a substantial 3% to global carbon emissions, with the production of one metric ton of primary aluminum releasing 10-20 metric tons of CO2. Thus, reducing these emissions is critical to promoting environmental sustainability within the industry. This article meticulously examines this pressing issue and analyzes potential strategies to foster a greener aluminum production process. The intrinsic value of this study lies in its capacity to make substantive contributions towards environmentally sustainable practices in this specific industrial domain. [ABSTRACT FROM AUTHOR]

The paper deals with the possibilities of using alkali silicate based inorganic binders for automotive industry aluminium castings production. In recent years, inorganic binders are coming back to the foreground and their manufacturers are developing new processes, which are starting to progressively supersede organic binder systems. Paper describes known knowledge about classic alkali silicate binders with focus on hardening processes and on improving their technological properties. Trends from the area of development and the use new alkali silicate based inorganic binders are also shortly described. As part of the experimental work, specific methods of producing samples were developed, with the help of which properties such as disintegration were subsequently evaluated by measuring abrasion and residual strengths. Characteristics such as residual compressive strength or shear strength at different thermal loads were also evaluated. When comparing the laboratory results with the results of de-coring in real conditions, a high degree of correlation was achieved, which makes it possible to determine the optimal recipe/procedure for the production of geometrically complex cores. [ABSTRACT FROM AUTHOR]

Decarbonisation of the Nordic power sector entails substantial variable renewable energy (VRE) adoption. While Nordic hydropower reservoirs can mitigate VRE output's intermittency, strategic hydro producers may leverage increased flexibility requirements to exert market power. Using a Nash-Cournot model, we find that even the current Nordic power system could yield modest gains from strategic reservoir operations regardless of a prohibition on 'spilling' water to increase prices. Instead, strategic hydro producers could shift generation from peak to offpeak seasons. Such temporal arbitrage becomes more attractive under a climate package with a [euro] 100/t C[O.sub.2] price and doubled VRE capacity. Since the package increases generation variability, lowers average prices, and makes fossil-fuelled plants unprofitable, strategic hydro producers face lower opportunity costs in shifting output from peak to off-peak seasons and encounter muted responses from price-taking fossil-fuelled plants. Hence, a climate package that curtails C[O.sub.2] emissions may also bolster strategic hydro producers' leverage. Keywords: Electricity markets, Equilibrium modelling, Hydropower, Market power, Carbon policy, 1. INTRODUCTION Future climate packages in OECD countries envisage deep decarbonisation of the power sector by relying upon variable renewable energy (VRE) sources, viz., wind and solar power. For example, [...]

Copyright of Journal of Hubei Open Vocational College is the property of Journal of Hubei Open Vocational College Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)