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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.

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.

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.

Perfluorinated carbon compounds (PFCs) CF4 and C2F6 are potent greenhouse gases that are generated in aluminum reduction cells during events known as anode effects (AEs). Since the 1990s, the aluminum industry has made considerable progress in reducing PFCs from conventionally defined and detected AEs. However in recent years, the industry has noted the presence of unaccounted PFCs that are generated outside the conventional AE definition. Two additional AE categories have been proposed, namely low-voltage, propagating AEs (LVP-AEs) and nonpropagating AEs (NP-AEs) that relate to continuous, background levels of PFC emissions. These unaccounted PFC phenomena may help explain the recent discrepancy between industry accounting and atmospheric measurements of global PFC emissions. Estimates from AGAGE, a global network of atmospheric observatories, suggest as much as 50% underaccounting of PFCs by the aluminum industry in the 2006–2010 period. The following work reviews this discrepancy and the potential role played by LVP-AEs and NP-AEs.

Efficient smelters currently consume roughly 13 MWh of electricity per ton of aluminum, while roughly half of that energy is lost as thermal waste. Although waste heat is abundant, current thermal integration in primary aluminum facilities remains limited. This is due to both the low quality of waste heat available and the shortage of potential uses within reasonable distance of identified waste heat sources. In this article, we present a mapping of both heat dissipation processes and heat demands around a sample facility (Alcoa Deschambault Quebec smelter). Our primary aim is to report opportunities for heat recovery and integration in the primary aluminum industry. We consider potential heat-to-sink pairings individually and assess their thermodynamic potential for producing energy savings.

The symposium “Extractive Metallurgy of Aluminum,” held in New York in 1962 under the auspices of The Metallurgical Society (TMS) of the American Institute of Mining, Metallurgical and Petroleum Engineers Inc. (AIME), was a groundbreaking event in the United States for the entire aluminum industry. As a result of two years of organizing, 55 contributors, 31 embracing the production of aluminum, freely shared results of research done within their companies or universities during this tentative opening up of communication and sharing of data and discoveries that had occurred previously only in a few conferences in Europe. The amicable interactions and success of this meeting led to the beginning of annual meetings organized by the Light Metals Committee of TMS. The consensus was emphatic that sharing non-competitive technology and discovering some of the trends in the strategies of competitors were all conducive to advancing competitiveness of the whole aluminum industry. Raising the awareness of the effectiveness of in-house R&D would enhance the innovations and creativity of all technologists. So in 1970, in Denver, the TMS Light Metals program began its series of annual symposia involving international industries, suppliers, and academia. This paper explores the inaugural TMS Light Metals symposia with the objective of commenting on how selected papers were “cutting edge” and how they influenced the electrolytic production of aluminum and inspired competitive research, improved funding, the attraction of future technologists, and “centers of excellence” for research into the Hall–Heroult process, novel processes, and advanced materials.

With a global population approaching 7 billion, there simply is not enough primary aluminum available to indefinitely meet demand. Developing optimal effectiveness of aluminum recycling is critical to ensuring an adequate aluminum supply for future generations, while also contributing to a more sustainable world. This paper presents a framework for achieving substantial progress that integrates key elements of the aluminum recycling landscape: engineering, communication, public policy, and actionable sustainability strategies.

The “old fashioned” and imprecise approach of using a dip stick is still employed to measure the crucial level information in electrolysis baths in the aluminum industry. The dip stick method is based on manually immersing a metal rod into the cell and observing the marks left by the molten bath components to estimate the metal/electrolyte interface and the bath level. However, methods to improve height estimation have been developed in recent years, although none has yet been introduced as part of the routine measurement procedure in the aluminum manufacturing industries. An attempt is made here to give an overview of the promising methods for measuring or estimating the different levels of the bath constituents in an electrolysis cell. Broadly, these methods can be classified into two categories: methods based on innovative physical equipment with the necessary sensors and transducers, and inferential methods which exploit existing measurement data. The first category encompasses many physical and chemical disciplines, whereas the second relies on inferential methods employing approaches sometimes called soft computing or soft sensors. Both approaches are presented and discussed in this paper.

The aluminum industry, through the International Aluminium Institute (IAI), has developed a number of objectives for improvement in the environmental performance of its production facilities. The IAI measures performance against these objectives on an annual basis. The latest data indicates that the industry, while doubling production since 1990, has reduced its emissions of perfluorocarbon greenhouse gases by almost 80% over the same period. However, the largest potential for emission reduction is through the use of aluminum products in energy-saving applications, such as lightweight vehicles, green buildings, and packaging that protects food and medicines, as well as through the recycling of these products at the end of their useful life.

As a consequence of the increasing aluminum production in Iceland, local processing of aluminum skimmings has become a feasible business opportunity. A recycling plant for this purpose was built in Helguvik on the Reykjanes peninsula in 2003. The case of the recycling plant reflects increased concern regarding environmental aspects of the industry. An interesting characteristic of this plant is the fact that it is run in the same facilities as a large fishmeal production installation. It is operated by the same personnel and uses—partly—the same equipment and infrastructure. This paper reviews the grounds for these decisions and the experience of this merger of a traditional fish melting industry and a more recent aluminum melting industry after 6 years of operation. The paper is written by the original entrepreneurs behind the company, who provide observations on how the aluminum industry in Iceland has evolved since the starting of Alur’s operation and what might be expected in the near future.

The aluminum industry is a leading proponent of global sustainability and strongly advocates the use of recycled metal. As the North American primary aluminum industry continues to move offshore to other geographic areas such as Iceland and the Middle East, where energy is more readily available at lower cost, the importance of the secondary (i.e., recycled metal) market in the U.S. will continue to increase. The purpose of this paper is to take an integrated, industry-wide look at the recovery of material from demolished buildings, shredded automobiles, and aging aircraft, as well as from traditional cans and other rigid containers. Attempts will be made to assess how the different alloys used in these separate markets can be recycled in the most energy-efficient manner.

It is now possible to assess the impact of the production processes of aluminum on the environment and to describe some of the ongoing responses and opportunities for improvement. This is compared with the benefits of aluminum in transportation, where the growing usage in various forms of transport due to its low density, high strength, and ability to be recycled enables reduced mass, increased fuel efficiency, reduced emissions and increased safety. It is the purpose of this paper to compare and contrast the emissions generated in the production of aluminum with the benefits accruing from its increased use in transportation.

Aluminum and alumina prices and production volumes dropped significantly in 2008 due to the worldwide economic recession. This paper provides a comprehensive analysis of the current state of the aluminum industry and its outlook for the future.

This article provides an overview and characterization of the worldwide aluminum industry and its importance to the world economy. It reviews the current state of the industry, addressing the complete process from primary production through aluminum products to recycling. Global markets for aluminum and the future challenges and directions of the industry are also discussed, and the historical milestones in the aluminum industry are noted.

Recycling behavior and the motivations behind recycling are being analyzed in a collaborative study between the Sloan Industry Center for a Sustainable Aluminum Industry, the Center for Aluminum Technology, Secat, and the Gatton College of Business and Economics at the University of Kentucky in Lexington. The goals of this study are to determine why people recycle and to find ways to motivate people to recycle more, using Fayette County, Kentucky, as a sample study. It is hoped that the information gathered through educational and motivational efforts in this county can be used on a larger scale in communities throughout the United States.

The aluminum can industry is facing a new challenge in declining recycling rates in the United States. The economic benefits of aluminum recycling are wide-spread and important not only to the U.S. aluminum industry, but to the economy in general. With an Alfred P. Sloan Foundation grant, Secat Inc. and the University of Kentucky, through the Center for a Sustainable Aluminum Industry, are conducting a project in Fayette County, Kentucky, to understand and improve recycling rates using Six Sigma methodology. This application of Six Sigma is the first methodological attempt at improving the recycling rate. To date, the preliminary process map has been identified and an initial estimate of the true recycling rate has been developed. The information gathered during this project and described in this article is expected to serve as a steppingstone to a national effort to increase U.S. recycling rates. The result, it is anticipated, will be increased economic development opportunities.

A special event at the 2005 TMS Annual Meeting in San Francisco in February 2005 was a plenary session sponsored by the TMS Light Metals Division, the TMS Aluminum Committee, and the Aluminum Association. The purpose was, as stated in the symposium title, to discuss “The role of technology in the global primary aluminum industry, both today and in the future.” The participants were leaders from the primary metals groups of the world’s largest aluminum companies. This global industry session attracted a high number of attendees, with 500 or more leaving standing room only, and it was the best-attended event of the 2005 TMS Annual Meeting. The speaker presentations were followed by a panel discussion with the opportunity for the audience to ask questions and provide their comments to the presenters. While the presentations were generally off-the-record, with neither a proceedings nor distribution of the PowerPoint slides, the authors feel that a recap of the session’s roundtable discussion would be of interest to both the attendees and to the community of TMS. Thus, the transcript of the discussion is given here. The transcript has been edited slightly to improve its readability, but the content of the questions and answers was not altered. The participants were: Cynthia Carroll, president and chief executive offi cer of Alcan Primary Metal Group, Canada; Truls Gautesen, president of Hydro Aluminium Primary Metal, Norway; Wayne Hale, senior vice president of operations, Sual Holding, Russia; Xiangmin Liu, vice president, Aluminum Company of China Limited (Chalco), China; Valery Matvienko, deputy general director, Aluminium Business, Rusal, Russia; Bernt Reitan, executive vice The Role of Technology in the Global Primary Aluminum Industry Today and in the Future

Since it was established in 1995, the annual Aluminum of Siberia Conference and Exhibition has developed into what is now recognized as the leading forum in the Russian aluminum industry. This article reviews the most recent event in the series. Sessions offered included aluminum production, casting, alumina production, carbon materials, and ecology and labor protection.

The emergence of China as a global economic force has influenced the technical enterprise generally and a number of industries specifically. The aluminum industry is an example, with effects on consumption and demand as well as production and supply. This article reviews these areas from both a historical and future perspective.

The devastating suddenness of the energy crisis in the western United States in 2000–2001 and its decimating cause of the shutdown effect on the aluminum smelters in the Northwest should not have been a surprise to the industry. Indeed, while portentous signs of such a probability were apparent for more than a generation, they were overlooked or disregarded. In specific, the case of Kaiser Aluminum’s smelter at Chalmette, Louisiana, provides an instructive example of how changes in energy supply can lead to the shutdown and dismantling of one of the world’s largest aluminum reduction facilities of its time. Will similar dismantlement be the fate of any of the Northwest aluminum smelters presently in a shutdown, standby status?

Increasing demand for aluminum-based products and globalization of the aluminum industry have contributed significantly to the higher consumption of aluminum scrap for re-production of wrought aluminum alloys. The recycling of wrought auminum alloys not only fills market demand, but does so economically. It is a well-known fact that recycling wrought aluminum alloys from collected scrap consumes 15 times less energy than producing primary aluminum, and the cost of internal scrap is marginal. This paper examines opportunities for recycling scrap to solve the ongoing problem of raw material shortages for European producers of wrought aluminum alloys.

In 2001, the aluminum industry continues to benefit from technical innovations made in alloy development, product-manufacturing technologies, and processing equipment over the last century. This paper examines the top ten alloy, product, and process developments that have shaped the industry’s production methods and markets. The interrelationships among the alloy development, process innovations, and markets are highlighted. Omitted are details about patent literature or the inception of many technologies; the major criterion for placement on the list was impact on the total industry.

John J. Chen (University of Auckland): When the program for the TMS 2000 Aluminum Reduction Technology sessions was put together, there was much media attention on the so-called Y2K bug. With the dawning of the new millennium—the correct start-date of the new millennium aside—we felt that it would be timely to take stock of the technology and discuss what the direction and needs are for research and development in the new millennium. Hence the title, Aluminum Reduction Technology—Where to from Here. It was felt that the best way to achieve a free interchange of ideas would be to deviate from the normal TMS paperpresentation format. Instead, we decided on having a panel of experts who represent the broad cross section of the industry, in terms of geography, academe, industry, etc. We would also encourage comments and questions from the audience. We are very grateful to the panelists who have accepted our invitation to present their viewpoints, which will act as the seed for further discussion and debate. We are very pleased that Dr. Nolan Richards agreed to chair the discussion. Nolan Richards (Consultant): Firstly, this is your panel. These people have consented to be up here to be of service to you. They are going to present ideas— it could be their visions, their wishes, or their complaints. It is up to you to react. I hope that some things that are said up here will inspire you to ask questions and comments. We came to this symposium, I believe, to be inspired and to learn something. I love what Barry Welch said on Monday—think out of the box. It reminded me of some innovative experiments that we conducted together in our early years at Reynolds [Reynolds Metals Company]. That’s how I perceive what Dr. Welch and others are going to inspire you to think out of the box.

There are currently more than 50 different types of PB cell technologies being used in the aluminum industry. This article reviews the current status of prebake cell technology worldwide with a look at some of the leading aluminum producers and their technologies. The nomenclature for prebake cells is also discussed.

In the last two decades, the aluminum industry has seen the demise of the ASP chloride process as an alternative production path and a reduction of papers on carbothermal production options. At the same time, there has been a steady stream of articles proposing the use of drained-cathode technology (by a wettable titanium-diboride coating) and others extolling the virtues and potential materials for inert-anode technology. There was also a rush of smelter technology papers in the early 1980s claiming an achievable energy consumption of less than 12.5 kWh/kg. However, the recent emphasis has been a shift to high amperage technologies that are less energy efficient but more cost efficient. Current efficiencies in excess of 96 percent can be routinely obtained by new technologies, and even aged technologies can be retrofitted to perform at 95 percent. The challenge is to lower cell voltages, but one of the key limitations is the need to maintain adequate superheat to avoid sludge formation and electrolyte-concentration gradients. Electrochemical technologies face the same problems and challenges as present technology; the requirements are even more acute and demanding. These challenges can probably be met, however, and the industry is undoubtedly faced with interesting times as it continues to strive to be competitive.

By partnering with the OIT, the aluminum industry has taken an important step in planning the technology needs of their industry for the next 20 years. Under the leadership of the Aluminum Association, the industry has become proactive in defining its long-term goals and the technology requirements to meet them. Over the next year, the development of a more detailed aluminum-research agenda will help to realign research in companies, universities, and national laboratories. To ensure that the roadmap responds to customer requirements, the aluminum industry is working to improve its understanding of the technology and research needs of each of its end-use customers. Although the ultimate success of this endeavor may not be known for several years, the aluminum industry-government partnership can serve as an effective model for collaboration efforts in other U.S. industries.

This article charts the remarkable growth of the aluminum industry in Russia that propelled the country to its present position as number-two world producer. In this article, the current situation and future prospects are reviewed against a backdrop of global economics, production and consumption, and supply and demand indices. Developments and achievements are outlined, together with supporting company strategies for further growth and improvements. These are discussed in terms of product. It is concluded that aluminum as a material and the Russian industry share a bright future together.

Although many typically regard the casthouse furnace as a simple piece of equipment, in reality the furnace design has a remarkable effect on final metal quality and efficiency of operation. Heat exchange, burner design, process control, and the refractory lining all contribute to the overall performance of the furnace. The most efficient design may vary from plant to plant, but poor design will definitely lead to higher production cost and difficulty attaining the highest quality products.

In the history of materials and human events it sometimes happens, however rarely, that a particular time and a consequent circumstance merge to create the opportunity for a happenstance event; subsequently, the event is accorded monumental status within its sphere of application. Such was the case of the small but very expensive aluminum pyramid that was set atop the Washington Monument on its completion in 1884 to serve the functional purpose of a lightning rod. In retrospect, this can be considered a watershed event in the subsequent emergence of the modern massive aluminum industry.

During the last 50 years, some of the most important developments in the Hall-Heroult process include improvements to bath chemistry, alumina feeding, anode and cathode quality, and process control. In addition, progress has been made in cell size and design, production capacity, energy consumption, and magnetic field modeling.

Electromagnetic casting is used within the aluminum industry to cast approximately two million ton per year of metal. It is a semicontinuous casting operation where the metal is solidified without contacting a mold. Consequently, the surface of the ingot does not have the imperfections that mar the surface of ingots cast using other technologies. This paper reviews the development of the technology and examines the fundamental phenomena governing the operation of the caster and the structure of the ingots cast.

As concerns grow about the role that perfluorinated carbon compounds (PFCs) play in global warming, the aluminum industry is voluntarily exploring ways of reducing the volumes of CF4 and C2F6 generated during Hall-Heroult electrolysis. As these gases are produced only during anode effects, which are undesirable for other production reasons as well, aluminum producers are aggressively examining ways to reduce the number of anode effects that occur as well as their duration.

One of the most critical components of aluminum reduction technology is the anode. As the Hall-Heroult process is pushed closer and closer to its theoretical limits, every facet of anode manufacture and performance is being scrutinized to obtain optimum anode behavior in the reduction cell. A new anode plant design may help the world’s aluminum smelters solve some of their anode problems.

The properties of coal tar pitches have changed more in the last eight years than in the previous 40. Over the same period of time, the understanding of the influence of these properties on anodes has increased greatly. The definition of a good-quality pitch for the manufacture of anodes for the primary aluminum industry has changed radically. Pitches that would have been rejected 15 years ago are now preferred and are in high demand. Changes have been led in equal proportion by the pitch producers and by the primary aluminum industry. The increased pace of change will continue as the quest for higher performance is unending. Further advances will be achieved through closer cooperation between producer and user to define and redefine pitch quality in terms of what is the best compromise between what the customer wants and what the producer can practicably manufacture.

As the aluminum industry strives to improve productivity and efficiency, carbon baking technology is one area receiving attention. With the anode plant accounting for a significant portion of total smelter investment, completely new installations are often out of the question. But the alternative of retrofitting existing carbon baking furnaces can often provide incremental capacity, reduce fuel consumption, and cut unwanted emissions.

The Light Metals Division (LMD) is one of five technical divisions of TMS. Its mission is to serve professionals in the traditional and emerging light metals fields, and to fulfill this mission, the LMD relies on five committees representing specific technologies within the light-metals community. The long-established Aluminum Committee addresses technologies related to the primary aluminum industry and organizes the well-known Light Metals Program including Reduction Technology, Electrodes, Alumina and Bauxite, and Cast Shop Technology, at the TMS Annual Meeting. The Light Metals conference proceedings has developed into highly valued reference literature in the aforementioned areas. The Aluminum Processing Committee, founded in 2008, provides a forum for the downstream industry, mainly rolling, shape casting, and alloy development. The committee’s symposia organized at the annual meeting are currently published in separate proceedings, but in the future a common proceedings volume is planned, similar to the Light Metals book. The Magnesium Committee provides a forum for the exchange of science and technology issues associated with magnesium production and use. The magnesium program during the annual meeting has increased significantly in recent years, with papers published in the highly recognized Magnesium Technology. The Recycling and Environmental Technology Committee is a joint committee with the Extraction & ProcessThe Light Metals Division: Five Committees, One Mission