The Environmental Impact of Aluminum (And Why it’s Still Better Than Plastic)
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By SCA Community Engagement Fellow Hayden Sloan
Aluminum (or Aluminium, if you’re not from the US) is an abundant element within Earth’s surface— but getting it out of the ground is an arduous process, requiring heavy machinery to plow up acres and acres of land. Fortunately, the environmental impact of that process can be somewhat balanced out by post-mining rehabilitation, efficient recycling, and generally reducing our consumption.
The Process: Bauxite to Alumina to Aluminum
Aluminum is hidden in an ore called Bauxite. It’s a red dirt and clay mixture commonly found in Australia, Brazil, and India. If you’re looking for shining bits of silver in the ground, though, you won’t find it. Aluminum as we know it has gone through a lot to get to our supermarket shelves (among other amazing uses).
Bauxite is collected from the ground in an open-pit mining operation. It doesn’t sit very deeply in the earth’s crust, so some energy can be saved on drilling. However, to recover all the aluminum in an area, swaths of land must be bull-dozed to reveal the dirt and ore underneath.
Once collected, the bauxite ore has to be refined. Facilities use chemical processes to weed out other compounds like silica and iron oxides until they have a wealth of white, powdery alumina (aluminum oxide-Al2O3). It looks like a thick chalk dust at this point.
Via electrolysis and even more chemical reactions, requiring high amounts of heat, alumina is dissolved, melted, and passed through a current so that it loses the oxygen bound to it, turning it into pure, molten aluminum. After all that, two tonnes of alumina become one tonne of aluminum.
Chemistry not your thing? This video can show you what the process looks like!
The Impact: Land, Air, and Water
As you have probably noticed, turning Bauxite into Aluminum requires a lot of energy and has a variety of environmental impacts.
Both open and underground mines affect the plant and animal life immediately surrounding an area and beyond for multiple generations. Clear-cutting trees and grasslands contributes to biodiversity loss, habitat loss, carbon emissions, and erosion. Mining operations have taken this damage into account more and more in recent years, incorporating plans to restore and regrow natural habitats once mining is completed.
All refining processes use varying levels of electricity and water, which can cause higher carbon emissions, create air and water pollution, and even noise and heat pollution.
The Silver Lining
If refining aluminum sounds incredibly resource-intensive, that’s because it is. Extractive industries like mining (for any ore, element, oil, or gem) are not our most earth-friendly activity. Refining takes a lot of energy, as well. It’s hard to live in our modern world without extraction, so we have to work harder to use our resources efficiently and make conscientious decisions about how we apply those resources.
Mining may be rough, but there is a silver lining (pun intended)! Almost 75% of all the aluminum ever produced in the US is still in use today. That’s how well aluminum can be and is recycled! Aluminum is not only a great material because it’s lightweight and conducts heat well, it can also be recycled indefinitely (if uncontaminated).
There’s still a lot of aluminum lost to landfills, which can be improved by post-consumer recycling. Did you know that if you wash off your aluminum foil it can also be easily recycled? Recycle all your aluminum! But be careful not to contaminate the recycling stream with food particles or grease.
The best thing about aluminum is that your recycled soda can can become another soda can in as little as two months. In contrast, other items like plastics can only truly be “down-cycled,” as reworking it causes the quality to degrade. Eventually, all of our plastic ends up discarded, without the possibility of another life. There are lots of ways to recycle your bottles, but have you seen any for thin plastics like cling wrap?
If you have the option, go for aluminum! And no matter what, remember to always recycle!