Because of its versatility, aluminum lends itself to numerous applications. In fact, it's the second-most used metal after steel, with annual primary production reaching 24.8 million tons (22.5 million metric tons) in 2007 [source: International Aluminum Institute]. Much of that output goes to the 187 billion aluminum cans produced worldwide [source: Novelis]. The automotive industry is aluminum's fastest-growing market. Making car parts from aluminum -- everything from wheel rims to cylinder heads, pistons and radiators -- makes a car lighter, reducing fuel consumption and pollution levels. By some estimates, a car incorporating 331 pounds (150 kg) of aluminum should see fuel consumption reduced by 0.43 gallons per 100 miles [source: Autoparts Report].
Here are some other important uses of aluminum.
- Automotive and transportation: car and motorcycle parts, airplane bodies and parts, license plates
- Building and construction: siding and roofing, gutters, window frames, interior and exterior paint, hardware
- Cans and closures: beverage and food cans, bottle closures
- Packaging: aluminum foil, foil wraps, aluminum trays, candy and gum wrappers
- Electrical: power and telephone lines, light bulbs
- Health and hygiene: antacids, astringents, buffered aspirin, food additives
- Cooking: utensils, pots and pans
- Sporting goods and recreation: golf clubs and baseball bats, lawn furniture
Aluminum by the Numbers
Amazingly, most of the aluminum ever made is still in use today. That's because it can be recycled over and over again without losing its quality. Most aluminum that gets recycled comes from one of three sources: used beverage cans, parts from old automobiles and scrap collected during the manufacture of aluminum products [source: World Book]. Aluminum can recycling is one of the great successes of the modern sustainability movement (If you're a big recycler, be sure to read What one thing should I recycle?). The first national can-recycling program began in 1968, and today, about 66 billion cans are recycled each year in the United States alone [source: Alcoa].
Aluminum can recycling is a closed-loop process, which means the new product made after the recycling process is the same as the one before. There are six steps to closed-loop can recycling:
- Old aluminum cans are taken to an aluminum reclamation plant.
- The cans are shredded into small pieces.
- The pieces are fed into a melting furnace.
- The molten aluminum cools and hardens into rectangular ingots.
- The ingots are formed into thin sheets of aluminum.
- The thin sheets are used to make new cans.
Much of the innovation in the aluminum industry is related to improving the efficiency of production and recycling. But, as we'll see in the next section, the demand for aluminum will only grow as new and exciting applications emerge.