Most of today’s aluminum is either refined from bauxite, its primary ore, or it is recycled aluminum. Recycling aluminum is increasingly common, as aluminum is infinitely recyclable and the recycling of aluminum products and alloys is very energy efficient when compared to refining bauxite.
Refining bauxite into metallic aluminum happens in two stages. Bauxite is first mined, often from shallow deposits. Canada does not mine bauxite but significant bauxite refining and smelting operations exist around Shawinigan, Quebec and Kitimat, British Columbia. Bauxite ore is refined into alumina (aluminum hydroxide – Al2O3) using a process called the “Bayer process.”
The Bayer process adds sodium hydroxide to the bauxite, essentially converting the aluminium oxide in the ore to sodium aluminate, and leaving non-dissolved silica, iron oxides, and titanium dioxide to be discarded. The mixture is then filtered, the alkaline solution is cooled, and aluminium hydroxide precipitates as a white, fluffy solid. This material is then heated again and the aluminum hydroxide decomposes to aluminum oxide, giving off water vapor in the process.
The aluminum oxide (alumina) is then sent to another process in an aluminum smelter where it subjected to electrolysis using the Hall/Héroult process, which separates out the aluminum metal. This step is very electricity-intensive. Finally, the molten pure aluminum is siphoned off to make aluminum ingots.
If this sounds complicated, it is. In fact, the metallurgical knowledge to refine aluminum really only came into force in the late 1800s. There were other processes of obtaining aluminum metal known from about 1825, but these were cumbersome and extremely expensive. As a result, in the late 1880s aluminum was more expensive than gold! Wikipedia Aluminium Production refinement states that “Napoleon III of France is reputed to have held a banquet where the most honored guests were given aluminium utensils, while the others made do with gold.”
In 1884, the capstone of the 555 foot tall Washington Monument was chosen to be made of 100 ounces of pure aluminum, a huge extravigance at the time even though the capstone was just a few inches high. But by the early 1890s, the Hall/Héroult refining process was in use, and the value of pure aluminum dropped precipitously. Nonetheless, Gizmodo notes that the capstone of the Washington Monument remains an iconic piece of Americana.
DexSpan™: Your Own Solid Aluminum Treasure
The ubiquity of aluminum these days makes it hard to imagine its value just 150 years ago. But today, aluminum’s value is found in its strength (when alloyed with other metals); its easy handling, and its weather resistance. DexSpan™ know this, and offer lines of aluminum framing for decks and docks. Their knowledge of aluminum’s durability makes it possible for DexSpan™ to offer a lifetime warranty on their frames.
Installation is simple, requiring few tools. The pieces are designed for easy assembly, and DexSpan™ includes detailed installation guidance.
At the end, your deck or dock will be framed on a rigid, stable, and durable frame, and you will be amazed at the speed of installation.
If you want a deck equally able to impress people 150 years in the future and 150 years in the past, an aluminum deck frame from DexSpan™ is your solution. Contact The Deck Store today see how easy framing in aluminum can be.