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. Through a coordinated exploration—actively involving every sector of aluminum manufacturing and application—of processes and alternatives offered in this paper , the global aluminum industry could set a reasonable, self-imposed energy/carbon neutrality goal to incrementally increase the supply of recycled aluminum by at least 1.05 pounds for every one pound of incremental production via primary aluminum smelter capacity.

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.

This paper explores the robustness of materials selection decisions when using various life-cycle assessment methods. Improving the environmental performance of vehicles is a topic of growing concern met by today’s designer. One approach to this goal is through vehicle mass reduction, enabled through the implementation of a growing array of material candidates. While LCA methods are available to provide quantitative input into this selection decision, LCA applications are evolving and distinct. Specifically, this paper surveys the major analytical variations of LCA implementations and explores the implications of one major variant when applied to an automotive materials selection case study involving aluminum. This case study examines analytical variations in treatment of recycling by exploring allocation methods that affect product EOL. Preliminary results indicate that the choice of analytical method can have real impacts on individual metrics and there are sets of analytical variation over which strategic results are strongly affected.

In light of escalating fuel prices and the ongoing climate change discussion, sustainability considerations are currently taking a more prominent role in material selection decisions for automotive applications. This paper presents a new methodology for total life-cycle cost analysis and employs a case study involving the use of aluminum in automotive applications. This study is aimed at developing a new sustainability model to quantify the total cost encountered over the entire life-cycle of a vehicle considering all four life-cycle stages: (1) pre-manufacturing, (2) manufacturing, (3) use and (4) post-use. Also, the paper presents a quantitative evaluation of the environmental impact of using aluminum material in a vehicle. The paper compares the use of aluminum with the traditional use of steel alloys in a given automotive application by providing details of economic and environmental performance of the vehicle over the total life-cycle.

The experienced multi-disciplinary team, assembled by Phinix, LLC, has the broad experience, flexibility and capability to successfully design, build and commissions the Waste-to-Energy (WTE) plant for Lexington Fayette Urban County Government (LFUCG) and manage the resulting carbon credit benefits.

The continuing growth of aluminum alloy usage in transportation applica¬tions, notably passenger automobiles and minivans, and the demonstrated economic benefits of recycling alumi¬num-rich vehicles increase the need to seriously consider the desirability of designing recycling-friendly alloys. This article focuses on that aspect of the recy¬cling process for passenger vehicles. The goals are to illustrate the opportunities afforded by identifying and taking full advantage of potential metal streams in guiding the development of new alloys that use those streams. In speculating on several possible aluminum recovery practices and systems that might be used in recycling passenger vehicles, likely compositions are identified and pre¬liminary assessments of their usefulness for direct recycling are made. Specific compositions for possible new recycle-friendly alloys are suggested. In addition, recommendations on how the aluminum enterprise, including industry, academia, and government, can work together to achieve the aggressive but important goals described here are discussed.

From this short survey it is concluded that the dilemma of the 900,000 tons of aluminum UBC waste is best tackled by working with Options 1 ( collection of “clean” UBC ) and 2 (collection of UBC as commingled waste). These options are clearly more straightforward and cost efficient than recovery from an existing landfill, Option 3 (recovery of UBC from an existing landfill). Only when these two simpler options have been optimized will it be possible to make a realistic estimate of the benefits of further recovery procedures directly from a landfill.

A key element for realizing long term sustainable use of any metal will be a robust recycling industry.To expands secondary production, it is necessary to reduce the barriers to return, collect, and process recycled materials. One such barrier is the mismatch between the composition of returning postconsumer scrap and current alloy specifications. This paper examines the use of linear optimization models to provide detailed strategies for secondary metal processors, remelters, and product designers in their selection and specification of alloys. A case study involving typically recycled aluminum components is presented to evaluate a set of scrap friendly alloys proposed by the authors. Specific focus will be given to the impact of scrap compositional uncertainty in the alloy design process. Initial results show that utilization of these new techniques provides a systematic approach to inform alloy designers on business-critical decisions that provide both increased scrap consumption and related economic benefit.

For decades, thousands of obsolete private, civil, and military aircraft have been sitting in “graveyards,” while the demand for recycled aluminum continues to increase. The aircraft provide an obvious source of valuable metal. However cost effective recycling of aircraft is complex because aircraft alloys are (a) typically relatively high in alloying elements and (b) contain relatively higher levels of impurities than required of many newer aircraft alloys to optimize their toughness and other performance characteristics. This paper describes (a) potential aircraft recycling process, (b) the technical and logistic challenges, and (c) options to address those challenges in a practical and cost-effective manner. A program addressing these issues is laid out in this paper.

The growth in aluminum usage in transportation applications, the decline in aluminum beverage can recycling, and the increasing reliance of the domestic fabrication industry on secondary aluminum have combined to create new needs in both the materials design and processing space. This presentation will detail the history and future projections for aluminum recycling, emphasizing the increasing importance of mixed scrap streams in the makeup of secondary aluminum. To most economically utilize these scrap streams, new approaches to developing acceptable materials processed to control properties suitable for an expanded range of applications are needed. How the aluminum enterprise, including industry, academia, and government can work together to meet these important but aggressive targets and transform recycling from strictly an environmental imperative to an economic development opportunity will be discussed.

Recycling aluminum alloys has been shown to provide major economic benefits. As a result, it is appropriate for the aluminum industry and the U.S. as a whole to identify, develop, and implement all technologies that will optimize the benefits of recycling. This paper focuses primarily on alloy design for optimizing the reuse of recycled metal; this is both the most forward looking area as we move toward a more recycle friendly world, and the most overlooked for its potential in maximizing the recycle loop. Some specific approaches to alloy design for recycling are put forth, and some specific compositions for evaluation are proposed. Options for moving forward to further capitalize on the advantages of aluminum recycling are also addressed.

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 a Sloan Foun¬dation grant, Secat Inc. and the Univer¬sity 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 method¬ology. 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 stepping stone to a national effort to increase U.S. recy¬cling rates. The result, it is anticipated, will be increased economic development opportunities.

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.

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

Probably the most significant property of alumi¬num is its ability to be recycled repeatedly with¬out loss of product integrity and minimal material loss through oxidation (~1-2%). Further, recycling saves ~95% of the energy and emissions as compared to making it from the original ore, a key factor in a carbon-constrained world. The recycling advantage is demon¬strated every day with the beverage can, which can be sold, consumed, recycled, and be available again in the store in as little as 60 days. In the past few years, the volume of aluminum recycled from automotive applications has sur¬passed that from beverage cans. This growing aluminum use in automotive applications, especially of recycled alu¬minum, is significant in that it decreases vehicle mass, im¬proves fuel efficiency, and reduces emissions. Eventually, this application is anticipated to beneficial.

Aluminum consumption in automotive applications has maintained consistent growth in the past 30 years and is expected to continue to climb to meet the growing demand for more energy-efficient vehicles. Recycling post-consumer aluminum to build new vehicles will further reduce manufacturing life-cycle energy consumption and emissions leading to significantly lower production costs. To take full advantage of recycling automotive aluminum alloys, a guideline for the recycling practice and design of recycle-friendly alloys such as cost benefits is needed, while meeting the property requirements. Formability is one of critical properties for aluminum vehicle body panels and strongly depends on alloy composition and processing. The forming limit curve (FLC) offers the opportunity to determine process limitations in sheet metal forming and is used in the estimation of the stamping characteristics of sheet metal materials. The comparison of deformations on stamped metal sheets with the FLC leads to a security estimation of the stamping process. Numerical analysis has also been applied to simulate the forming process of automotive parts and to predict the forming behavior of aluminum alloys. A combination of numerical analysis and the FLC comparison can serve as a good guideline to optimize the recycling process and alloy compositions of automotive aluminum alloys.

In this study, the global texture evolution in a 2 mm gauge hot band of continuous casting AA5052 aluminum alloy, annealed at 449 °C for 4 hours, was investigated. Samples were deformed to three different strain values under a near equi-biaxial stretching condition. Their textures were. The major and minor strains of these samples were measured using an automatic strain analysis system. The texture evolution in the different layers through thickness of these samples was measured using X-ray diffraction. It was found that cube and Goss ({110}􀂢001􀂲) components varied markedly during biaxial stretching, while brass, copper and S components were changed only slightly. Cube orientation was decreased, whereas Goss orientation was increased, which was more profound in the surface region of the hot band during stretching. A weak fiber-like component, {110}􀂢hkl􀂲, was developed during biaxial stretching. In addition, a {110}􀂢111􀂲 component was also found to exist mainly in the surface.

Driven primarily by energy considerations, there has been a major change in the geographical distribution of primary aluminum production over the past few decades, even as the energy efficiency of the process has been improved. Meanwhile, in the United States, production of aluminum from secondary sources increased nearly ten-fold. This paper discusses past and projected future trends, emphasizing the changes in energy savings potential as the industry comes to rely more on remelting and less on primary production.

The aluminum fabrication industry has become more vital to the global economy as international aluminum consumption has grown steadily in the past decades. Using innovation, value, and sustainability, the aluminum industry is strengthening its position not only in traditional packaging and construction applications but also in the automotive and aerospace markets to become more competitive and to face challenges from other industries and higher industrial standards. The aluminum fabrication industry has experienced a significant geographical shift caused by rapid growth in emerging markets in countries such as Brazil, Russia, India, and China. Market growth and distribution will vary with different patterns of geography and social development; the aluminum indus¬try must be part of the transformation and keep pace with market developments to benefit.

Aluminum alloys have been used in bridge structures since 1933, when the first aluminum bridge deck was used to replace an earlier steel and wood deck on Pittsburgh’s Smithfield Street Bridge in order to increase its live-load carrying capacity. While still not considered a standard for bridge structures, aluminum alloys have much to offer for such applications, and continue to be used where their light weight, high strength-to-weight ratio, and excellent corrosion resistance satisfy service requirements.

This project was funded in response to call for proposals under the Aluminum Industry of the Future, Industrial Technologies Program (ITP) of the U.S. Department of Energy (DOE). The objectives of this program are to improve the efficiency of melting in the aluminum industry by;

• reducing the current energy requirements for melting aluminum by 25%
• reducing the generation of GHG, and NOx emissions from the melting of aluminum; and
• evaluating alternate metal melting technologies used in other industries that may have application to further efficiency improvements and emission reductions for the aluminum industry.

This article provides an overview and characterization of the worldwide alu¬minum industry and its importance to the world economy. It reviews the current state of the industry, addressing the complete process from primary produc¬tion 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.

This research project has successfully demonstrated that an increased understanding of the microstructure formation and improved computational tools can be used for improving the DC casting process for aluminum 3004 and 5182 alloys. The results lead to reduced scrap rates and increased energy savings. The project serves as a starting point for even more sophisticated models for the prediction of crack formation.

One of the breakthroughs from this project is having identified that an unfavorable combination of elements in alloys has a strong effect on crack formation. This is especially true when the copper and zinc contents are high in the alloy. Cracking due to the presence of trace elements or due to an unfavorable combination of elements in alloys were not fully recognized in the past and were usually explained as variations due to water quality. One recommendation of the project team is that the industry should pay attention on controlling the composition of the alloys to achieve minimized crack formation.

A successful project has been completed to understand the feasibility of using in line anneal technique to treat hot roll material as it emerges from the hot rolls. Design, erection and commissioning of a trial facility were successfully carried out at Aleris to produce sufficient amounts of material to evaluate material properties. Based on the successful conclusion of the trials design data has been generated that can be utilized for the construction of an inline anneal based plant either by retroactive fitment of the system or by the construction of a new plant at a Greenfield site.

During the course of the work it was proved that in line anneal can be utilized successfully to produce material comparable to DC cast material at much lower cost and meet the rigorous standards of the automotive industry.

This project led to an improved understanding of the mechanisms of dross formation. The microstructural evolution in industrial dross samples was determined. Results suggested that dross that forms in layers with structure and composition determined by the local magnesium concentration alone. This finding is supported by fundamental studies of molten metal surfaces. X-ray photoelectron spectroscopy data revealed that only magnesium segregates to the molten aluminum alloy surface and reacts to form a growing oxide layer. X-ray diffraction techniques that were using to investigate an oxidizing molten aluminum alloy surface confirmed for the first time that magnesium oxide is the initial crystalline phase that forms during metal oxidation. The analytical techniques developed in this project are now available to investigate other molten metal surfaces. Based on the improved understanding of dross initiation, formation and growth, technology was developed to minimize melt loss. The concept is based on covering the molten metal surface with a reusable physical barrier.

Project team has successfully performed on-site evaluations of commercial furnaces for benchmark and modeling establishment and validation. The furnace modeling tools for furnace design and operation parameter optimization have been developed. The “what if” scenarios studies of furnace re-design for aluminum industrial partners have been carried out for better energy efficiency. The three technical reports have been submitted and discussed with aluminum industrial partners. One project technical review meeting was hold at Lexington, KY. Several aluminum industrial partner specific technical reports were submitted and discussed. Project team will continue to refine the modeling techniques including melting model based on ProCAST, and provide “what if” scenario studies for melting furnace design and operating process optimization to improve energy efficiency.

The results presented in this final report clearly show the strong capabilities of the developed models in the course of this project. Temperature distributions, flow fields and liquid fraction evolutions can be determined for various burner tubes designs and configurations. The results can be used to optimize the design of melting or holding furnaces using immersion heaters. The models can also be used to examine the effectiveness of using immersion heaters for specific functions (e.g. melting, homogenizing molten metal etc.). Numerical simulations are effective and accurate methods of examining potential solutions and can significantly minimize the need for expensive experimental trial and errors.

Project team has successfully performed on-site evaluations of commercial furnaces for benchmark and modeling establishment and validation. The furnace modeling tools for furnace design and operation parameter optimization have been developed. The “what if” scenarios studies of furnace re-design for aluminum industrial partners have been carried out for better energy efficiency. The three technical reports have been submitted and discussed with aluminum industrial partners. One project technical review meeting was hold at Lexington, KY. Several aluminum industrial partner specific technical reports were submitted and discussed. Project team will continue to refine the modeling techniques including melting model based on ProCAST, and provide “what if” scenario studies for melting furnace design and operating process optimization to improve energy efficiency.