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Kaolinite clays can serve as an additional source of alumina in the Republic of Kazakhstan. The most promising is the Alekseevsky kaolinite deposit. To obtain high-quality kaolinite and quartzite products, it is necessary to develop special enrichment techniques, since no satisfactory results were achieved when using standard methods of gravitational enrichment of kaolinites. The paper presents the results of studies of the effect of preliminary chemical activation during the processing of kaolinite clays of the Alekseevsky deposit. Previously, the method of preliminary chemical activation of raw materials in a solution of sodium bicarbonate has proven itself well in the processing of various mineral raw materials. It was determined that during the preliminary chemical activation in a solution of sodium bicarbonate, changes occurred in the phase composition of the kaolinite fraction: the content of muscovite decreased almost twice; the phase of sodium aluminosilicate was formed. The dependence of the yield of Al2O3 in the kaolinite fraction on the temperature of chemical activation, duration, and the ratio of L:S and the concentration of the sodium bicarbonate solution during chemical activation. The optimal mode of preliminary chemical activation of kaolinite clay of the Alekseevsky deposit has been established: the temperature is 150 oC, the duration is 120 minutes and the concentration of sodium bicarbonate solution is 120 g/dm3. A basic technological scheme is proposed for the processing of kaolinite clays.

As a hazardous waste, secondary aluminum dross has troubled the aluminum industry for many years. A coupled life cycle assessment and life cycle costing method was used to evaluate the environmenta...

Aluminum industry depends on coal-tar-pitch as a binder to produce carbon anodes used for aluminum electrolysis. This binder is nonrenewable and mainly composed of polycyclic aromatic hydrocarbons ...

We build a frontier function model with technical and cost efficiency measures to assess the impact of energy costs on competitiveness in the aluminum industry, a heavy energy consumer, by identifying what may be attributed to price and quantity effects. First, we estimate a data envelopment analysis model and measure the efficiency scores using the Farrell and Tone approaches. Then, we explain efficiency scores with a set of environmental factors using a truncated regression model, applying the double-bootstrap method proposed by Simar and Wilson in 2007. By considering the Tone efficiency scores, we highlight the fact that efficiencies are differentiated depending on geographic region and production technologies. This could explain the loss of competitiveness observed in certain industrial units in recent years. We also highlight other factors that impact cost efficiency, such as global market share, multinational status and the exchange rate with respect to the dollar. These factors have a significant, positive effect on relative efficiency in terms of aluminum smelter costs. Our results provide a better understanding of the reasons for the changes in this industry, which has been marked by major technological and economic shifts, and allow us to assess the role of energy in these changes.

The article discusses the prospects of recycling the most massive wastes of aluminum production (namely, used cathode blocks of electrolyzers, gas treatment dust, gas treatment residue, and flotation tailing). It have been indicated the volumes of wasteaccumulation and a special attention has been focused on the need of their disposal with a view to improve the environmental conditions of the territories adjacent to the industrial zones. Specific characteristics of the generated waste have been determined, which indicate the possibility of their secondary use and transfer from waste to by-products.Existing technical solutions relevant to the issue have been reviewed, and the reasons preventing their implementation have been explained. The most promising methods of waste processing to be carried out successfully in the current economic conditions have been identified. Spent cathode blocks can be used at ferrous metallurgy enterprises (in blast furnaces and converters) as a substitute for expensive coke and fluorspar, and finely dispersed waste can be used at cement enterprises. The areas have been determined that in the future will significantly increase the volume of processing and the demand for these wastes of the aluminum industry in technological processes of ferrous metallurgy. The possibilities for cooperation between aluminum refineries and ferrous metallurgy enterprises, as well as other related industries, were emphasized in detail.

In the aluminum industry, the needs of predictability of the kinetics of precipitation during the artificial aging processes increase as the targeted applications require the maximisation of proper...

In the aluminum industry, the initial operation comprises the production of its oxide, Al2O3 (alumina) from ores, mainly the bauxite. The Bayer process is, in practice, the only used to produce alumina generating a huge amount of hazardous waste known as red mud. Among the proposed alternatives to consider red mud a useful by-product, the incorporation into clay ceramics allows large quantities to be reutilized as construction products. Several research works investigated this alternative but were limited to single clay incorporation without specific application in building construction products. In the present work the possibility of producing bricks and roofing tiles for building construction with plain red mud and incorporations separately, in two different clays, with low and high plasticity, was for the first time investigated. Both red mud and clays were characterized. Corresponding ceramics fired at 850, 950 and 1050°C were evaluated for their technological properties. The results indicated that plain red mud fired at any of these temperatures might be used as bricks according to the Brazilian standards. It could also be used for roofing tiles production when fired at 1050°C. Application in bricks for building construction and a preliminary environmental assessment were for the first time presented. Keywords: Red mud ceramic, Plain ceramic, Clay incorporated ceramic, Bricks and tiles

This study tries to measure the performance of aluminum and small and medium industries (SMEs) in Yogyakarta which are considered to be underdeveloped. Based on the development of the number of businesses, over the past ten years the number of SMEs has continued to decline. Based on these conditions, this study tries to use the industry life cycle approach and market trends to analyze the position of the aluminum industry in Yogyakarta City in particular and Indonesia in general to measure the performance of the industry. Descriptive analysis results collected through written questionnaires are complemented by content analysis of the results of interviews and focus group discussions (FGD) with stakeholders to get more in-depth information to draw conclusions and provide suggestions for the development of aluminum SMIs in the city of Yogyakarta. The results obtained from this study are the aluminum industry in the city of Yogyakarta is in an early maturity position so it needs a strategy to extend the industrial life cycle. This research is still limited to one industrial center and is discussed from the perspective of SMIs, the next research will produce more comprehensive results with data from several industrial centers and involve large industries to get a more complete view of the relations between industries. This research is one of the few studies that discuss the performance of the industry in terms of product life cycle in Indonesia which is a fairly good approach in developing development strategies and for survival.

Introduction. In the production of aluminum, one of the main adverse factors is the air pollution of the working area with f uorine-containing compounds and dust-gas-aerosol mixture, the impact of which can lead to health problems in workers. When establishing the connection of morbidity with the profession, it is important to assess the exposure loads of harmful substances. T is aspect of research in the aluminum industry is not suf iiently covered in the literature. T e aim of the study is to quantify the exposure loads of priority toxicants in workers of the main professions of aluminum production, depending on the applied technologies of aluminum electrolysis. Materials and methods. Exposure loads (EL) of chemicals at workers of aluminum production were calculated taking into account the data of a long-term assessment of the working area air for the content of the main harmful substances in workshops with technology of self-baking anode (TSA) and modernized using technology of prebaked anode (TPA). Results. It has been established that with the use of the traditional electrolysis technology (TSA), the average annual EL indicators in the professions of the electrolysis cell, anodechik and crane operators f uctuated noticeably in the dynamics of long-term observation, exceeding the indicators of the control EL. It is shown that the modernized electrolysis technology (TPA) allows to reduce the EL indicators of chemicals, with the exception of hydrof uoride — one of the priority components of the chemical factor. T e actual EL indicators of this substance in the professional groups did not depend on the applied electrolysis technology and, as before, exceeded the EL control indicators. Conclusions: Calculations of EL by harmful substances in the production of aluminum have shown that when using TSA, electrolysis cells and anodetes experience the greatest EL, exceeding control indicators, and the lowest — crane operators. T e transition to a modernized TPA leads to a decrease in the EL indicators, with the exception of the hydrof uoride, a priority component of the chemical factor.

Fluorine is a highly reactive element and readily hydrolyzes to form hydrogen fluoride and oxygen. Hydrogen fluoride reacts with many materials both in the vapor phase and in aerosols. Fluorides are naturally-occurring components of rocks and soil and are also found in air, water, plants, and animals. Fluorine gas pollutes the atmospheric environment originating from aluminium smelting plant operating at Renukoot, district Shonbhadra. Volcanic emissions also emit hydrogen fluoride. A detailed investigation undertaken during 2008-2012 to objective fluoride Distribution in Aquatic Environment in Vicinity of Aluminum Industry and its Correlation with Rainwater Chemistry and Weather Parameter. For this investigation Collect 57 rainwater samples in rainy season in pre-cleaned and sterilized polyethylene bottles of two litre capacities from roof of the local society of Hindustan Aluminum Company Renukoot, district Sonbhadra. The collected samples were analyzed for pH, Electrical Conductivity, Sodium, Potassium, Calcium, Carbonates, Bicarbonates, Chlorine, Sulphate, Fluoride, Residual Sodium Carbonates, and Sodium Adsorption Ratio with standard procedures.

In order to recover the waste heat of aluminum dross and carbon resource in carbon residue, the waste heat recovery process of aluminum dross by coupling of physical and chemical method was propose...

Introduction.Th e aluminum industry belongs to the industry with a high status of occupational pathology. The study of metabolic bases and hygienic aspects of fl uorosis is a priority section of modern occupational health. Organ failure occurs in a separate group of workers, despite the equivalent conditions of production and may be due to biochemical polymorphism.The aimof the study was to explore the associative relationship of molecular genetic, biochemical markers with the nature of chronic fl uoride intoxication in workers of the aluminum industry.Materials and methods. Th e complex of clinical and genetic parameters of workers of Novokuznetsk aluminum plant with the determination of the content of harmful impurities in the air of the working areas was evaluated. Statistical analysis was carried out using IBM SPSS Statistics 22.Results. Over 25 years of observation, the maximum risk of intoxication was observed in the workplaces of electrolyzers, anodes against the background of metabolic disorders. Th e associative relationship of CYP, GST, SOD genes with the nature of fl uoride intoxication was determined.Conclusions.Th e development of fl uorosis is predetermined by the hereditary component. Markers associated with the dynamics of metabolic maladaptation allow to predict the course of the disease.

Red mud (RM) is one kind of basic solid waste produced from aluminum industry. RM is usually stored by the method of land stockpiling, which has caused serious environmental and safety issues. Bittern, a by-product of salt manufacture, is abundant in China. But the utilization rate is low, less than 20%. The disposal of waste bittern has become a challenge that attracts much attention in water industry. In this article, Mg/Al/Fe layered double hydroxides (Mg/Al/Fe-LDHs) were synthesized using the above two wastes by a coprecipitation method and characterized by X-ray diffraction (XRD) and scanning electron microscopy. The XRD results showed that LDHs were successfully synthesized. Then, the flame-retardant properties and thermal properties of Mg/Al/Fe-LDHs in ethylene vinyl acetate (EVA)/LDHs composites had been tested by cone calorimeter test (CCT), limiting oxygen index (LOI), smoke density test (SDT), and thermogravimetry–Fourier transform infrared spectrometry (TG-FTIR). The CCT results showed that the heat release rate (HRR) of the EVA/LDHs composites significantly decreased in comparison with that of pure EVA, and EVA2 sample showed the lowest peak value of HRR value of 204.59 kW m−2. The LOI results showed that EVA3 had a highest LOI value of 28.3% in all the samples. The SDT test indicated that Mg/Al/Fe-LDHs were beneficial to the smoke suppression performance of EVA composites. TG-IR results showed that EVA/LDHs composites had better thermal stability than EVA.

Introduction. The leading place in the Russian Federation and in the world is occupied by cardiovascular diseases (ischemic heart disease, hypertension, and peripheral vascular diseases), which are the main cause of disability and death worldwide. The aim of the research was to study the prevalence of cardiovascular pathology in workers of the aluminum industry. Material and methods. We examined 66 workers of the aluminum facility without occupational pathology and 135 employees who never worked in adverse working conditions (the control group). All the examined subjects were men; the average age accounted for 52.08±0.4 years. Results. The study showed the workers of the aluminum facility to develop such diseases of the cardiovascular system as arterial hypertension, atherosclerosis with lesions of peripheral and extracranial arteries, as well as multifocal atherosclerosis more often than in those who do not work in adverse working conditions (the control group). Conclusion. The unfavorable occupational factors of aluminum industry are an additional risk factor for the development of cardiovascular pathology.

The Hall–Herault process is the only methodology applied in the industrial production of aluminum. Energy saving has long been the focus of the aluminum industry since its invention. Nowadays, the pursuit of high productivity, low DC energy consumption and large-scale cell adds new urgency to energy saving, among which the improvement of magnetic-hydro-dynamic (MHD) stability in aluminum electrolysis cells plays a very important role. This article reviewed the developments and applications of the measures in improving MHD stability in terms of structure, effectiveness, simulation, pilot and industrial results. Also some studies were conducted on a TiB2 wettable cathode. At the end, some suggestions on further reduction of energy consumption in the future are proposed.

The influence of the periodicity of diagnostic measurements on the operational state of high-voltage transformers is considered. Examples of defects of switching devices of converter transformers and methods for their detection are given. The rationale for the importance of recognition of defects at an early stage of their occurrence is given. The influence of the multiplicity of overvoltages on the service life of converter transformers in the aluminum industry is investigated. Based on the analysis of the service life of converter transformers of one of the powerful aluminum plants, where 83% of converter transformers have exhausted their standard service life, it is shown that in 40% of cases it would be possible to avoid their failures, with timely detection and elimination of emerging defects. Examples of defects of OLR (on-load regulators) of converter transformers and methods for their detection are given. The importance of recognition of defects at an early stage of their occurrence is substantiated. A method for chromatographic analysis of dissolved gases in transformer oil has been developed for the qualitative determination of defects and ways to eliminate them. Examples of diagnostics of converter transformers at operating voltage and working load are given, providing the best quality operational characteristics of converter transformers. The periodicity of diagnostic measurements and the reduction of defects and failures has been substantiated. The question of diagnosing the state of the converter transformer TDNP-40000/10 at an enterprise of the aluminum industry is investigated. Currently, diagnostic methods are being developed based on chromatographic analysis of dissolved gases in transformer oil. The presented method of evaluating the operating parameters of transformers allows for the safe operation of high-voltage transformers and enables to increase the reliability of the power supply scheme of aluminum industry plants.

The focus of this study was to utilize red mud (RM), an aluminum industry waste, for the preparation of various catalysts for the synthesis of glycerol carbonate (GC) from glycerol (GL). A series o...

The paper presents reliability analysis of a rodding anode plant in aluminum industry with multiple unit failure and single repairman. Manufacturing process of raw aluminum blocks in this plant passes through eight stations. Failure of any of the stations brings the plant to a complete halt, except the butt & thimble removal press stations because of the parallel standby arrangement, and does not affect the system operation completely unless both the units fail. Six years of real maintenance data on component failures, repairs and associated costs are used in this analysis. Measures of system effectiveness is gauged through reliability indices such as mean time to plant failure, availability of the plant, busy period of repairman and expected number of repairs. Effect of repair rate, failure rate and repair cost on system performance w.r.t. revenue is shown graphically. Theory of Semi-Markov and regenerative stochastic processes is used in the analysis.

Impurities found in metal are a major concern for the aluminum industry as some of these may contribute to a decrease of current efficiency or impact metal quality. In the present work, the effect of process parameters on phosphorous and other impurities present in pot metal was investigated using statistical analysis. Factors responsible for the increase of phosphorous in the metal and operational parameters to maximize current efficiency were studied. In addition, sudden changes in phosphorous content in pot metal were investigated, and a mechanism is proposed to account for observed phosphorous and process changes.

As a typical energy-intensive industry, the cost of electricity constitutes more than 40% of the total production cost of electrolytic aluminum in the China's electrolytic aluminum industry, suggesting the presence of co-movements between electricity prices and electrolytic aluminum prices. However, in the case of China, the common belief that electricity prices and electrolytic aluminum prices are correlated was not supported by the observed inconsistent frequent changes over the last decade, particularly after the 2008 financial crisis. To account for such inconsistency, this paper explores the incomplete transmission of electricity prices to electrolytic aluminum prices by employing a structural demand-supply model where market power, rotated demand, and quantity-dependent marginal cost in the electrolytic aluminum industry are incorporated. Empirical results show that there is a relatively stronger transmission effect of electricity prices on marginal cost of producing electrolytic aluminum but a much weaker transmission effect on the equilibrium price of electrolytic aluminum. Results from decompositions of electrolytic aluminum prices and marginal cost not only confirm the presence of incomplete price transmission, but also reject two conventional explanations concerning market power and input costs. In addition, a potential theoretical explanation is proposed to facilitate understanding the evolution of electrolytic aluminum prices.

Abstract Aluminum production generates enormous spent pot lining (SPL) waste of around one million tons yearly, and these wastes are usually disposed in landfills. Hence, the technical feasibility of SPL gasification using both equilibrium and reactive high-fidelity modeling was evaluated in this study. Three SPL with different washing treatment, i.e., water (WWSPL), acid treated (ATSPL), and full treated (FTSPL, a combination of both water and acid washing) were used for the modeling. The equilibrium model considered twelve species, while the high-fidelity simulation was modeled with multiple species. Moreover, the high fidelity model is governed by the steady non-isothermal Navier–Stokes equation coupled with the discrete phase in Eulerian–Lagrangian scheme. The process metrics were assessed via the produced syngas fraction (CO/H2) and gasification efficiency (GE). The equilibrium analysis of WWSPL, ATSPL, FTSPL, respectively, resulted in GE of 40, 65, and 75%. The corresponding syngas molar fractions for CO and H2 were 0.804 and 0.178 at 1450 °C; 0.769 and 0.159 at 1100 °C; and 0.730 and 0.218 at 1150 °C. These results suggest the potentiality and feasibility of gasifying the treated SPL, which was considered in the high-fidelity. Although the results show different trend from equilibrium for the FTSPL gasification (i.e., small molar fraction of CO2 and H2O and high syngas fraction dominated by CO at 0.75 and 0.1 H2 at best GE of 70%), it re-emphasizes the potential of the gasification of FTSPL as recyclable/renewable energy source. Graphical abstract

Perfluorocarbons (PFCs) do not affect stratospheric ozone depletion; however, they have extremely long atmospheric lifetimes. They are very stable because of the strength of the carbon–fluorine bond, one of the strongest in organic chemistry, and it is because of their inertness that PFCs are powerful greenhouse gases (GHGs). CF4 has a global warming potential (GWP) over 100 years 6,630 times more potent than CO2, whereas C2F6 and the lesser known C3F8 have GWPs of 11,100 and 8,900, respectively. The high GWP of atmospheric PFCs led to an increase of public concern about the effects of their accumulation in the earth’s atmosphere in the 1990s. At that time significant PFCs were only considered to occur during ‘anode effects’ (AEs) in the aluminum industry. There was a renewed worldwide concern about greenhouse gases which focused attention on PFC emissions from aluminum smelting. In response, aluminum producers initiated aggressive programs to decrease both the frequency and duration of AEs at most smelters globally. International voluntary programs to reduce AE frequency and duration proved to be exceptionally successful as PFC emissions were reduced in ten countries by 31%–78% relative to 1990 levels; the overall average reduction in PFCs for countries was 46%. This paper provides a historic overview of the discovery of PFCs, and highlights some of the first investigators in every phase of the journey to understand, measure, account for, and reduce the emission of these potent GHGs.

Предмет исследования (наблюдения) – распространенность различных уровней мотивации на здоровье и здоровый образ жизни, распространенность эмоционального выгорания, негативной аффективности и социального подавления у работников производства алюминия. Цель исследования – изучение роли психологических факторов в формировании приверженности к профилактическим и реабилитационным мероприятиям у работников алюминиевой промышленности. Методы исследования. Опросы проводились по опросникам «Индекс мотивации к здоровью и здоровому образу жизни», DS14, Спилбергера-Ханина, Торонтской шкалы алекситимии (TAS), В.В. Бойко, Н.И. Влах. Проведен опрос 122 работников алюминиевой промышленности, находившихся на обследовании и лечении в клинике НИИ комплексных проблем гигиены и профессиональных заболеваний. Основные результаты. Определена распространенность различных уровней мотивации на здоровье и здоровый образ жизни и распространенность синдрома эмоционального выгорания среди работников производства алюминия. Выявлена ассоциация негативной аффективности и мотивации на здоровый образ жизни. Область их применения. Медицина труда, профессиональная патология, медицинская психология. Выводы. Работники алюминиевого производства существенно различаются по уровню мотивации на здоровье и здоровый образ жизни. Негативная аффективность ассоциирована с пониженным уровнем мотивации на здоровье и здоровый образ жизни. Выявлено высокое распространение лиц с синдромом эмоционального выгорания среди работников алюминиевой промышленности. Роль психологических факторов в формировании приверженности к профилактическим и реабилитационным мероприятиям у работников алюминиевой промышленности нуждается в дальнейшем изучении., Subject of research – the prevalence of various levels of motivation for wellness and a healthy lifestyle, the prevalence of emotional burnout, negative affectivity and social suppression among aluminum industry workers. Objective of research – the research of the role of psychological factors in the formation of adherence to preventive and rehabilitative measures among workers in the aluminum industry. Methods of research. The surveys were conducted using the «Index of motivation for wellness and healthy lifestyle» questionnaires, DS14, Spielberger-Khanin by Toronto alexithymia scale (TAS), V.V. Boyko, N.I. Vlakh. A survey was conducted with 122 workers in the aluminum industry who were examined and treated at the clinic of the Research Institute for Complex Problems of Hygiene and Occupational Diseases. Results. The prevalence of various levels of motivation for wellness and a healthy lifestyle and the prevalence of burnout syndrome among aluminum production workers were determined. An association of negative affectivity and motivation for a healthy lifestyle was revealed. Field of application. Occupational medicine, occupational pathology, medical psychology. Conclusions. Aluminum production workers significantly differ in the level of motivation for wellness and a healthy lifestyle. Negative affectivity is associated with a decreased level of motivation for wellness and a healthy lifestyle. A high prevalence of people with burnout syndrome among workers in the aluminum industry was revealed. The role of psychological factors in the formation of adherence to preventive and rehabilitative measures among workers in the aluminum industry needs further studying.

This chapter briefly reviews the development of aluminum electrolysis, as well as the electrolysis cells and carbon anodes in the aluminum industry. In addition, the shortcomings of electrolytic cells and carbon anodes used in the aluminum industry are introduced. Reading this part enables readers to understand the development of aluminum electrolysis and to read the rest of the book smoothly.

Dr. Alton Tabereaux retired from Alcoa a long time ago, but never quit working in the aluminum industry. He continues to be active in smelting technology advancement, and in serving the aluminum industry and particularly the light metals community. He is world renowned not only for his technical contributions to aluminum smelting technology but equally important for his dedication to teaching and training younger generations, providing consultancy and technical support to operations. He serves the light metals industry with a unique technical background and knowledge in areas from environment protection, helping to stewardship government policies, to strengthening aluminum society. In this special tribute session, I am honored to renew our learning of Alton and his major technical achievements—looking back from his very early career as a young scientist at Reynolds Metal Co to later becoming a world renown industry icon.

This chapter introduces the inert anode and points out that the inert anode can overcome the shortcomings of the electrolytic cells and carbon anode. The development, advantages, and disadvantages of various inert anodes and electrolytic cells are introduced. This chapter also focuses on the cermet inert anode developed by American Aluminum Company (Alcoa), which is considered to be the best and most promising inert anode. In addition, the shortcomings of cermet inert anode and the problems that hinder its popularization and application in the aluminum industry are introduced.

Ore processing and metal manufacturing industries generate huge quantity of residual wastes. Emphasis has been laid on the residual products of aluminum industries, e.g., red mud. The industry utilizes bauxite as raw material to extract aluminum out of it. Extraction of aluminum being power intensive, all the aluminum industries have captive power plants which generate huge quantity of ash as waste product in addition to red mud which comes out through the process of alumina (Al2O3) extraction. In the absence of any effective technology that can utilize red mud, industries have to incur heavy expenses in terms of land and space for storing red mud resulting in increased cost of aluminum production. Such a situation calls for an effective, economic and environment-friendly method to combat the challenges of disposal of the waste produced by such industries. One of the most common and feasible ways to utilize red mud in bulk is to utilize the wastes for civil construction, e.g., construction of embankments, roads, etc., utilizing the waste material. This paper aims at characterization of the waste material, i.e., red mud and ash through laboratory experiments. Analyzing the various aspects of their geotechnical parameter attempt has been made to characterize the mix of ash and red mud as well as cement and red mud. Result obtained through laboratory experiments has been discussed.

In this paper, citric acid (CA) is chosen as an additive for the treatment of bauxite residue, a by-product generated by the aluminum industry. The potential of CA to improve geotechnical ...

Работа посвящена аналитическим процедурам в аудите дебиторской (ДЗ) и кредиторской (КЗ) задолженностей для организаций алюминиевой отрасли. Целью исследования является адаптация аналитических процедур в аудите ДЗ и КЗ с учетом рисков и отраслевой специфики. Задачи исследования: раскрытие специфики ДЗ и КЗ, а также специфики алюминиевой отрасли и ее влияния на бухгалтерскую (финансовую) отчетность, классификация рисков для выявления проблемных мест. The work is devoted to analytical procedures in the audit of receivables (hereinafter-AR) and payables (hereinafter – AP) for organizations of the aluminum industry. The purpose of the study is to adapt analytical procedures in the audit of AR and AP taking into account the risks and industry specifics. Research objectives: disclosure of the specifics of the AR and AP, as well as the specifics of the aluminum industry and its impact on accounting (financial) statements, risk classification to identify "problem areas".

This paper presents a comparative analysis between Model I and Model II of in an aluminum industry. Both models present the reliability analysis. The first model consists of a single component in each of the eight machines, assumed that the failure of any component at a particular machine is taken as a single failure and only one repairman working with the system and any failures should wait until the repairman finished the repair from the previous failure, whereas the second model consisting of a single component with multiple repairmen.The factory works clock by time and any breakdown in any of the machines influences the plant to a total shutdown circumstance. However, only 2nd machine has the standby adjustment, and do not disturb the system operation absolutely unless both of them break down. Six years historical data on costs of repairs/replacements failures and repairs of the plant systems are collected to analysis and to estimate failure, repair and cost rates from the statistics. System efficiency measurements such as MTPF, A 0 , B 0 and V 0 were obtained. The regenerative point and Semi-Markov processes used for the study of academic analysis.

Pot tending machine (PTM) constitutes an essential asset for electrolytic aluminum industry. This paper proposes an improved genetic algorithm for PTM scheduling problem, the problem of scheduling a fixed number of PTMs to do some types of tasks for each electrolytic cell. There are several constraints, and several task types in the scheduling problem, for example, PTM must keep a safety distance between each other in order to prevent dangerous collisions and one electrolytic cell may have several types of task to be done with the help of PTM. Firstly, this work put forward a novel chromosome structure called "2+1" and a method called within-class to deal with the problem using genetic algorithm adaptively. In addition, the paper use between-class method and mutation of the job number to improve diversity of solutions for genetic group. To enhance efficiency of genetic algorithm and keep cooperation with adjacent PTMs, this paper also raises a heuristic initial condition. Experimentation shows the proposed algorithm has a satisfying performance for PTM scheduling.

The aluminum consumption in India of 2.5 kg per capita is way below the global average of 11 kg per capita. In the future, India will require additional annual consumption of 16 million tons of aluminum. Due to the energy‐intensive nature of aluminum production coupled with its projected growth, there are sustainability concerns for this industrial sector. This paper examines some opportunities available for sustainability improvement in an existing aluminum plant using coal‐based electricity. An industrial sustainability index (ISI), as previously developed by the authors, is here to quantitatively evaluate the magnitude of sustainability improvement through a natural gas‐based combined cycle (NGCC) power generation. Two modes of sustainability improvement are examined: (a) NGCC with surplus power generation and (b) NGCC with doubling of production capacity. It is observed that the ISI values can be increased by 5 to 6 times through the above modes, as compared to the existing model. The investment required for such sustainability improvement is expected to be less than that required for setting up a totally new plant. The direct carbon emissions for the existing plant are nearly 6.4% of the total carbon emissions, which may be eliminated by adopting new smelting technology now available, with the further possibility of sustainability improvement.

The CPC and CTP raw materials used for anode production are both manufactured from byproducts of other industries which makes the aluminum industry dependent on others for two key raw materials. Despite this, the industry has made steady improvements in anode quality and performance over the last 50 years. Production processes for CPC and CTP have become more sophisticated but changes in feedstock availability for these raw two materials are starting to be felt by the industry. Average CPC quality has changed quite significantly over the last 10 years but the industry has adapted well and this is expected to continue in the future. By contrast, CTP quality has been quite stable over the last 10 years but the impact of declining coal tar production is starting to be felt by the industry. The paper will review current and future challenges for anode producers and where the cutting edge for anode raw materials lies today.

This chapter introduces the reader to the energy use in different industries globally and displays the Nace rev. standard classification of industries, followed by the subclassification of manufacturing industries according to the same standard. In the subsequent subchapters the largest energy using industries are presented, in descending order based on their energy use globally: chemical and petrochemical industry, iron and steel industry, cement industry, pulp and paper industry, and aluminum industry. The presentation of these industries includes information on the products produced in each industry, the production processes and energy-related matters. Also, the mechanical engineering industry is briefly presented in the chapter.

X-ray fluorescence analysis was applied to assess the ecological state of the area potentially polluted by emissions of the aluminum industry and heat power engineering. Soil and pine needle samples were collected in areas with industrial activity and analyzed using wavelength-dispersive X-ray fluorescence (WDXRF) and total-reflection X-ray fluorescence (TXRF) techniques. Both techniques were validated using the matrix-matched certified reference materials. Different sample preparation procedures, such as fusion and pressing for WDXRF and acid digestion and suspensions for TXRF as well as quantification approaches (the external calibration for WDXRF and the internal standard for TXRF) were applied according to the features of the analyzed samples. The rock-forming oxides (Na2O, MgO, Al2O3, SiO2, P2O5, K2O, CaO, TiO2, MnO, and Fe2O3) and trace elements (V, Cr, Ni, Cu, Zn, Rb, Sr, Y, Ba, and Pb) were quantified in soils, as well as several elements (Na, Mg, Al, Si, P, S, Cl, K, Ca, Ti, Cr, Mn, Fe, Ni, Cu, Zn, Br, Rb, Sr, Pb, and Ba) were quantified in pine needles. Comparing the results of soils and pine needles analysis with the regional background values indicated a significant contamination pollution level of the studied area.

As the world's largest primary aluminum producer, China's primary aluminum industry (PAI) faces a huge challenge in reducing greenhouse gas (GHG) emissions. However, detailed research on presenting the historical trajectory of GHG emissions from China's PAI and identifying the main driving factors affecting its changes has not been completed thus far. This study quantifies the GHG emission trajectory of China's PAI from 1990 to 2018 and identifies the key driving factors affecting its changes. The results show that the total GHG emissions from China's PAI from 1990 to 2018 increased by approximately 18 times, reaching 481 Tg CO2-eq in 2018, of which 69 %, 17 %, and 14 % were electricity-related, fuel-related, and process-related, respectively. Additionally, the production activity effect is the main factor driving the increase in GHG emissions; however, the energy intensity and energy emission factor effects can effectively reduce GHG emissions. Based on this, scenario analysis is used to evaluate the GHG emission mitigation potential of China's PAI by 2030. According to our analysis, policy suggestions for mitigating the GHG emissions in China's PAI are proposed, including reducing the energy intensity, promoting clean energy use, controlling the production capacity, and decarbonizing electricity.

This paper examines how expected excess capacity fosters impediments to entry and incentives to exit. To examine this phenomenon, we apply the switching regime methods of Goldfeld and Quandt to a logit model using data from the U.S. aluminum industry over the period 1954 through 2010. The results show that both entry and exit decisions are statistically significantly affected by excess capacity. However, the correlation of entry and exit with capacity is more significant than with production. The evidence implies that excess capacity in the aluminum industry rises to be a substantial threat to entry only when the company produces ahead of demand growth. Excess capacity is also an impetus to exit during the later stage after primary aluminum production reverts to a declining trend.

Recent investigations on aluminum electrolysis cell demonstrated limitations to the commonly used tier-3 slope methodology to estimate perfluorocarbon (PFC) emissions from high-voltage anode effects (HVAEs). These limitations are greater for smelters with a reduced HVAE frequency. A novel approach is proposed to estimate the specific emissions using a tier 2 model resulting from individual HVAE instead of estimating monthly emissions for pot lines with the slope methodology. This approach considers the nonlinear behavior of PFC emissions as a function of the polarized anode effect duration but also integrates the change in behavior attributed to cell productivity. Validation was performed by comparing the new approach and the slope methodology with measurement campaigns from different smelters. The results demonstrate a good agreement between measured and estimated emissions as well as more accurately reflect individual HVAE dynamics occurring over time. Finally, the possible impact of this approach for the aluminum industry is discussed.

In this paper, the use of a clay residue as an adsorbent of the Remazol Black B (RB) and Remazol Red RB133 (RR) is studied. The residue is generated in a large amount on the Alluminum industry, especially the Arconic Alumínio S/A, Itapissuma, Pernambuco State. The thermally treated residue behavior was studied by performing a kinetic and equilibrium experiments. The variables evaluated in all experiments were the adsorption capacity (q) and adsorption efficiency (%). Adsorption experiments were performed at environmental conditions, with 50 mL of dye solution, with controlled steering speed, solution pH and adsorbent amount. In the kinetic studies was verified that for RB and RR, the system achieves the equilibrium state after 5 min. In the equilibrium, both reactive dyes obtained their maximum adsorption capacity (qm) with 1.0g of adsorbent and pH 4.0 and 6.5; with qm 0.98 mg·g-1 and 6.88 mg·g-1 for the RB and RR, respectively.

Red mud is the tailings generated from the production process of aluminum industry and is mainly stacked in open-air at present, so how to ensure the stability of red mud stockpile is very important. Regarding mud stockpile of Guizhou Aluminum Factory as the research object, this paper studies the physical and mechanical properties of Bayer red mud from wetting process, Bayer red mud from drying process, and sintering red mud through laboratory test and finally analyzes its stability under extreme rainfall condition in this region by the Geo-Studio software. The research results show that the red muds in different processes have big difference in physical and mechanical properties. The strength of sintering red mud is about 4.2 times of that of Bayer red mud from wetting process on average, and the strength of Bayer red mud from drying process is about 1.5 times of that of Bayer red mud from wetting process on average. So, the sintering red mud can be used as the subdam of red mud stockpile, to reduce the risk of collapse and dam break. The stability coefficients of the mixed stocking method under three rainfall conditions are 2.611, 2.597, and 2.631, respectively, all of which are above 1.0. It reveals that the dilatation scheme of using the sintering red mud with good engineering properties to stockpile the Bayer red mud is feasible. It can not only guarantee the safety and stability of red mud stockpiles, but also reduce the risk of red mud dam break and the capital investment of red mud yard.

China is the world's largest producer of primary aluminum and its production will continue to grow in the future. It is very important to optimize the technological development pathway for the low-carbon transition of primary aluminum industry given its continuing increasing energy consumption and carbon emissions. To that end, this study develops a bottom-up model, named National Energy Technology- Aluminum (NET-AL) model. The energy saving potential for three types of strategies are evaluated, including eliminating backward-production capacity, promoting advanced technology, and optimizing industry power structure. The key results are as follows: (1) All emission reduction strategies indicate that CO2 emissions could peak in 2025, and the cumulative emission reduction potential is 5.3% by 2050; (2) The advanced technologies have significant effects on energy saving. The role of promoting seven-effect tube evaporation technology and energy-saving combination technology of new conductivity structure are emphasized. Optimizing the power structure can effectively reduce indirect CO2 emissions, in which the largest penetration of hydropower-aluminum joint production is suggested to be 6.5%; (3) The joint impacts of the discussed three strategies, could not only lead to energy saving, but also brings economic benefits for China's primary aluminum industry.