Aluminum Upcycled: Sustainable Design in Historical Perspective
Author: Carl A. Zimring
Publisher: Johns Hopkins University Press (©2017)
Reviewed by John A.S. Green
With the very first sentence, “Waste is a product of design,” the reader is put on notice that Aluminum Upcycled is different. Thorough, well-researched, and thought provoking, the book is also timely because the use of aluminum in automotive (described in the “Metal in Motion” chapter) is projected to continue its strong growth. In fact, aluminum use in the automotive sector will grow at a faster pace than any time in history and is expected to exceed 460 lbs per vehicle by 2020, and reach 565 lbs per vehicle by year 2028.1 Hence, in the future there will be abundant metal to recycle or upcycle.
Recycling generally infers downcycling, where the value of the material is reduced or degraded in some manner. Upcycling, on the other hand, implies the waste product is both reduced in volume and its value enhanced by the new processing to give rise to more economically valuable products.
Overview
The contents of Aluminum Upcycled are split into two major parts. After a historical introduction, Part 1 is titled “Creating a Technical Nutrient,” and contains three chapters. The first chapter describes the rapid growth of aluminum production brought about by the U.S. government in response to mobilization and the second World War. Chapter 2 explores the enormous growth of aluminum applications and how, as a result, the metal became a major component of the waste stream, and Chapter 3 outlines how secondary aluminum itself has become a valuable commodity. At this time, manufacturers defined aluminum production as a hybrid of primary and secondary material for all applications. In fact, it was estimated by Martchek that, in 2009, aluminum products contained more than 60% scrap material.2
Part 2 is entitled “Designing Upcycled Goods” and also contains three chapters. Chapter 4 addresses “Metal in Motion” and relates to the use of aluminum in aircraft and automotive applications. The fifth chapter is devoted to aluminum use in “Covetable Furniture,” while Chapter 6 is entitled “Guitar Sustain,” offering an excellent history of the development of the guitar. In this last chapter, it was fascinating to learn how aluminum had played a key role in guitar development, providing some of the best examples of upcycling. The author highlighted how about 3 lbs of aluminum could be upcycled into a guitar that ultimately sells at auction for $312,000.
The book concludes with a brief discussion on “Designing for Sustainability.” This section appropriately balances the opening of the book, by stating, “Waste is a product of design, and design can salvage waste.”
A helpful aspect of the book is the extensive references. In addition to the conventional Index (six pages), it also provides 24 pages of Notes, containing copious information on further reading, additional suggestions, and helpful information for academic study or further research. This feature makes the document extremely information dense (highly useful for a reference document). It is probably the most thoroughly referenced aluminum text this reviewer has ever encountered.
Enhancing Scrap with Upcycling
According to Aluminum Upcycled, it is a moral obligation to limit waste and, therefore, it is environmentally responsible to recycle or upcycle metallurgical waste in order to limit damage to the land and emissions in the atmosphere. The book uses examples of aluminum manufacturing to show the benefits of upcycling.
The growth of the can market, as discussed Chapter 3, was dramatic in the early 1960s. This, in turn, resulted in considerable littering around the countryside, which spawned the need for can collection programs. At the same time, the blame for the littering was subtly transferred from can manufacturers to the general public. This provoked efforts to collect used cans, an activity that picked up rapidly—especially when the industry leader, Alcoa, realized that recycled material was a more economical source of aluminum raw material than conventional smelting. In 1970, 8 million lbs of cans were collected and recycled; this grew to 180 million in 1975 and 600 million in 1980. By 1994, secondary production had matched the primary production of metal from smelting. Now Novelis, the largest consumer of cans, claims to have recycled 38 billion cans worldwide in 2006, and hopes to reach a goal of 80% recycled content in its products by the year 2020.
Another aspect of upcycling presented in the book relates to the development of Ford’s aluminum pick-up truck. The new F-150 truck was touted as the best performing vehicle in 2014, when the traditional steel body was replaced with aluminum. The immediate weight savings of 700 lbs enabled better handling and performance, greater fuel efficiency, and added payload. This was the most significant use of aluminum in a popular, rather than a high-end, vehicle. The account of the preparations by Ford to facilitate the success of the new vehicle is comprehensive and impressive. For example, establishing a fleet of specially designed vehicles to transport the scrap promptly back to aluminum producers without contamination, training dealers to be knowledgeable about aluminum use and repair, and working to make their own facilities aluminum friendly were all significant investments made by Ford that should ensure the vehicle’s success for many years.
With the detail provided in the chapter, “Guitar Sustain,” it is easy to imagine the author must have grown up playing guitar in a band. The chapter so thoroughly describes the role of aluminum in the evolution of the guitar, it could be worthy of being published as a monograph on its own. It also serves to emphasize the incredible diversity of the applications of aluminum. Apparently, the durability and resonance of aluminum were recognized as early as 1928 and many guitar designs were developed at that time. The metal has been used in many ways in the body of the instrument, but it is especially used in the neck of the guitar. Here the close tolerances and rigidity permitted by the metal, and the fact that it does not warp like wood, enables the strings to vibrate, as long as the properties of the strings permit, to sustain the note. From the viewpoint of the metal, it is unfortunate that the excellent examples of upcycling in both furniture (in the previous chapter) and musical instruments require only modest quantities of recycled metal.
The concluding section, “Designing for Sustainability,” makes the point that although aluminum upcycling has been successfully demonstrated and has produced goods of durable value, the underlying issues of aluminum production, namely high energy use and environmental damage, still remain. The author notes, “The inconvenient truth of aluminum’s history is that while recycling rates have remained high, primary aluminum production continues to grow.” In fact, global primary aluminum production in 2014 exceeded 50 million tonnes. While many smelters in the U.S. have closed or moved offshore, the growth of primary production elsewhere, notably in China, has more than offset the U.S. reduction. Another factor that is not addressed in the book with this “inconvenient truth” is that the enormous growth of aluminum production has almost certainly curtailed the production and growth of other similar metals, such as zinc, magnesium, tin, and possibly even copper and titanium. Each of these metals have their own set of energy and environmental issues as well.
Aluminum Upcycled provides an excellent overview to the enormous growth of aluminum and to the history and design of the diverse applications of the metal. Indeed, it is a worthy addition to the literature of the aluminum industry.
As a footnote, it is particularly appropriate to consider a recent publication by Geoff Scamans of Innoval Technology, entitled “Upcycling; an important addition to our vocabulary,”3 in conjunction with this review of Aluminum Upcycled. Scamans’ publication notes the well known fact that only 5% of energy is needed to remelt and recycle aluminum compared to the original primary smelting process. It also points out that the main disadvantage of recycled post-consumer scrap is the build-up of impurities and inclusions, which are detrimental to the mechanical properties and corrosion resistance of the recycled material. The conventional approach to cope with impurity build up is either by a costly chemical refinement process, or by adding more pure metal—neither of which is economically desirable. It now appears that a promising approach may be to exploit a new melting procedure developed by Brunel University, which involves high shear melt processing. The technology apparently produces a higher grade of aluminum products from scrap. Examination of the microstructures produced by the high shear melt process shows a highly refined grain size (estimated by this reviewer as ~100 times finer than by conventional melting). This refined grain size should vastly increase the grain boundary surface area over which the impurities and inclusions are distributed, thereby reducing their detrimental effects on the mechanical and corrosion properties of recycled aluminum.
References
- Dickson, Jim, “Automotive Aluminum Enters the Fast Lane,” Light Metal Age, Vol. 75, No. 5, October 2017, pp. 14-16.
- Martchek, K.J., “Modelling More Sustainable Aluminum,” Intl. Journal of Life Cycle Assessment, Vol. 11, No. 1, 2006, pp. 34-37.
- Scamans, Geoff, “Upcycling; an important addition to our vocabulary,” November 2017, www.innovaltec.com/upcycling-blog.
Editor’s Note: This book review first appeared in the December 2017 issue of Light Metal Age. To read more articles from this issue, please subscribe.