Many years ago I earned a modest living as a UGA student by collecting and recycling aluminum cans from Athens roadsides. Even today, I still twitch when I see brightly-colored metal along the highway. Just like foam coffee cups, drink cans will never rot away.
Aluminum is one of the most marvelous inventions of the metal industry. In the 1880’s, a spectacle of nature combined with technology to produce the lightweight super-strong metal that we encounter daily. In Neuhausen, Switzerland, the course of the river Rhine has a quirk resulting from the last Ice Age. Instead of finding its old bed after laying dry for centuries, it cut into harder rock nearby. This created the spectacular Rhine Falls, sometimes dubbed the “Niagara of Europe”. Multiple branches cascade 36 feet down into calmer waters on their way to Basel, today’s chemical-pharmaceutical giant of Switzerland. Mechanical energy from that water supplied the massive electrical power that Paul Héroult needed to transform aluminum oxide into solid metal. His contemporary Charles Hall established a similar facility near the “real” Niagara Falls in New York. The Hall- Héroult process laid the groundwork for today’s industrial aluminum production.
Although aluminum doesn’t rust, it’s subject to oxidation. A rough, white corroded layer builds up on its surface. This layer then prevents further deterioration. The beer can tossed on the road or into a lake will remain there forever unless somebody picks it up. In November, 2007, Lanier was at a historic low level. On the exposed lake bottom at Clarks Bridge Landing, I found Schlitz beer cans from the early 1980’s and thousands of others. None of them had deteriorated.
Making disposable drink containers out of non-degradable metal doesn’t make much sense. But building aircraft does. Without aluminum, our planes would still be the heavy, slow machines made from steel and wood before World War I. Unlike steel, though, aluminum doesn’t “forgive”. Stress force on a steel girder or engine part doesn’t always cause lasting damage. But mechanical assault on aluminum parts will accumulate towards failure. This is why aircraft have a predetermined service life.
Recycling aluminum saves lots of energy. Making a beer can from recycled ones saves 94% of the power needed for new production. At about $0.30 paid currently by recyclers, it’s worth saving the cans up and turning them in for extra pocket money.
Rudi Kiefer, Ph.D., is a professor at Brenau University, teaching physical and health sciences on Brenau’s Georgia campuses and in China. His column appears Sundays and at gainesvilletimes.com.