actually pollute more than the process of extracting it from earth and producing new aluminum?I saw a report about 5 years ago on this and was wondering if anyone else had info on this subject.
Aluminum recycling is very cost-effective. Unlike most materials, metal recycling pollutes less than producing new product because most of the pollution is created by mining and smelting ore.
There is a significant savings - especially in electricity - about 90% less energy used to recycle aluminum than it takes to smelt ore and process it into useable aluminum.
I don't know the specifics, but I know it's not more than the extraction process. When aluminum is mined, it is in the form of bauxite ore. From this ore, only about half contains aluminum oxide. Then, from the mass of aluminum oxide (alumina), only about half of that will yield the pure aluminum we use for cans, airplanes, etc. So for every 2000 pounds that are mined, we only get about 500 pounds of aluminum. The process is extremely energy intensive and tears up the landscape where bauxite is mined. Transport adds to the pollution. Some of the biggest bauxite producers in the world are China, Russia, Canada, the United States, Australia, and Brazil, so overseas transport is frequently involved, especially in countries that use a lot of it. Furthermore, it is often shipped in bauxite or alumina form, when it is heavier to carry. Aluminum recycling, however, starts with the pure product and ends with the pure product, and the process is fairly quick. The aluminum can you recycle today will return to shelves within about 60 days. Furthermore, aluminum does not degrade in quality like some other materials so it can be reused indefinitely. The transport is also cut significantly, as recycled aluminum might only travel 100 miles or so to be refabricated.
Much less smelting required to convert pure aluminum into aluminum ingots than is needed to process boxite(?) into aluminum ingots.
