Has someone else been drinking from your can of pop? Quite likely, yes. But before that grosses you out, there’s something else you need to know. Between their sip and yours the can was heated to 1,221°F. At that temperature it the aluminum scrap melted, was then recast as an ingot and shipped out to a rolling mill. Basically, it was recycled.
Around 65% of aluminum pop cans get recycled in the US. That’s not out of any noble desire to “do the right thing,” it’s just economics. Making “primary” aluminum is really expensive, but it’s cheap to melt down, and it can be remelted an infinite number of times. That’s why there’s a healthy demand for aluminum scrap metal and it’s yet one more advantage of using aluminum extrusion.
“Primary” Aluminum Production
Aluminum is one of the most common elements on earth but it’s very hard to produce in its pure form. It starts out as bauxite, a clay-like material found mostly in tropical regions. A complex refining process then separates aluminum oxide, as known as alumina, from the silica and other minerals. Next, a second round of processing severs the bonds between aluminum and oxygen atoms. This is done by first melting the alumina and then blasting it with thousands of amps of electric current.
Massive quantities of electric power don’t come cheap. In fact energy makes up around 1/3rd the cost of this “primary” aluminum. “Primary” meaning that it’s never been used before.
What’s really interesting about aluminum is that this blast of energy is only needed once. Once you’ve made pure aluminum, even though the surface produces an oxide layer it doesn’t go back to being alumina. (Unlike iron which quickly becomes iron oxide, a.k.a. rust.) And because its melting point is a relatively low 1,221°F (660°C), remelting aluminum doesn’t take that much energy. In fact making remelted or “secondary” aluminum only needs about 5% of the energy required for “primary” aluminum production. Best of all, there’s no limit to the number of times scrap aluminum can be recycled.
Aluminum Scrap Metal Relevance to Metal Fabrication
The consequence of all this is that it’s cheaper to melt down and re-use aluminum scrap metal than to make new stuff. As a result there’s a healthy level of demand for scrap aluminum for metal recycling. So, when that workbench, picture frame or whatever else you made from aluminum extrusion reaches the end of its life, it still has some value. Unless there’s a sudden shortage of the metal you’re not going to profit on the deal, but it will save you from sending your junk to landfill. And landfill is getting expensive in many places!
Feel Good about Using Aluminum
Returning to pop cans, you can see now why they get recycled. Some experts estimate it takes just six weeks to go from stamping a can from aluminum to stamping it out again. Think of it as the pop can cycle of life. Yes, there are environmental benefits of aluminum recycling, but that aside, it just makes economic sense to reuse aluminum rather than burying it in the ground. So here’s another benefit of using aluminum extrusion in your metal fabrication projects: you can feel virtuous about supporting recycling efforts and saving energy.