Most people don’t put much thought into where aluminum comes from, but it’s something that manufacturers, fabricators, designers and consumers of aluminum products should give some thought to. That’s because the global supply of raw aluminum has a direct impact on their business, and in turn can affect the final cost of the products consumers use every day.
The process of extracting aluminum from the earth and refining it into usable and cost effective material is more complicated than people realize. One of the key steps in that process is smelting.
What is the aluminum extraction process?
The process by which aluminum is turned from bauxite into pure aluminum and then into the aluminum alloys found on today’s market is complicated. The primary step is technically called the Hall-Héroult process, although it is commonly referred to as aluminum smelting. This is when aluminum is converted from aluminum oxide, also known as alumina, into pure aluminum.
Smelting is an electrolytic process requiring a substantial amount of electricity. To put this into perspective, in a recent annual global estimate of 20,261 billion kilowatt hours of electricity generated, 3% of that total was expended in the aluminum refining process.
Aluminum is extracted from the aluminum oxide (Al2O3) by using a molten salt known as cryolite to dissolve the oxide. Carbon anodes are placed in the electrolyte bath and when an electrical current is run through the molten cryolite, the chemical bond holding together the aluminum and oxygen is broken. The molten aluminum, now pure, is deposited at the bottom of the electric cell, whereas the oxygen reacts with the carbon in the anodes, and the result is carbon dioxide.
The pure aluminum can then be cooled for further refinement and preparation for alloying.
Where is the current aluminum smelting capacity concentrated?
The need for a low cost electrical supply is the leading factor determining where aluminum smelters are located. For this reason, they tend to be situated near large power stations. Smelters are often in close proximity to hydroelectric plants, which helps to reduce the carbon footprint of the extracted aluminum, an increasingly important consideration.
It’s frequently the case as well that smelters will be found near transportation hubs, making it easier to bring in the alumina and then ship out the resulting aluminum.
China is by far the largest producer of smelted aluminum, with more than half of the primary global production in 2019. India and Russia are a distant second and third, followed by Canada, the United Arab Emirates, Australia, Bahrain, and Norway. The United States is ninth, followed by Saudi Arabia at tenth.
What factors are affecting global aluminum smelting capacity?
The United States has seen the number of smelters diminish from 23 in 1995 to just five at the present time. Most of the primary aluminum imported to the US comes from Canada, followed by the United Arab Emirates.
As mentioned, one of the greatest factors regarding the location of global smelting capacity is the availability of cheap electrical power. Canada has vast hydroelectric power generation available for aluminum production operations. Similarly, the UAE and other Arabian Gulf nations have built high efficiency, combined cycle power generation plants fired by natural gas, a byproduct of the crude oil extraction industries in those same countries.
In economies that don’t have a supply of cheap electric power, governments can step in to subsidize that cost and allow the smelters to operate at a profit. The implementation of stricter pollution controls globally is causing a shift to more sustainable forms of power generation and away from the cheaper power available from legacy coal fired plants.
Your Technical Services Professional
As global economic factors continue to fluctuate in 2021, it’s difficult to predict if and how global smelting capacity will be affected. The demand for aluminum will endure, however, especially as innovative new alloys are introduced to the market. If you need aluminum plate, sheet, bar or extrusions for your manufacturing pipeline, you need to work with a trusted and experienced aluminum supplier with a proven track record of reliability.
At Clinton Aluminum, our team of technical professionals makes working with our customers through every step of their procurement process our top priority. Contact one of our friendly and knowledgeable customer service representatives today to learn more.