Efficiently Using Earth’s Resources
Alcoa is the most fully integrated aluminum company in the world and also one of the largest. We have the capability to extract raw materials, process them into aluminum, convert the metal into end-use products, or sell them to others for further processing. We also recycle aluminum products at the end of their useful life.
The aluminum-making process begins with the mining of bauxite. We convert the bauxite to aluminum oxide and then to aluminum through processes that use fuels, caustic soda, lime, petroleum coke, coal tar pitch, aluminum fluoride, other chemicals, and water. We also mine coal and use fossil fuels and hydroelectric facilities to produce electrical energy, which is a major component of the electrolytic process required to produce aluminum metal from aluminum oxide.
The basic process requires approximately 5.5 metric tons of bauxite to produce two metric tons of aluminum oxide, which, in combination with one-half metric ton of carbon, can produce one metric ton of aluminum metal. (Note: The average metric tons of bauxite required to produce one metric ton of aluminum has changed over the last decade in the aluminum industry due to significant increases in mining bauxite with lower aluminum oxide content, especially in Australia, China, and Russia.)
Once produced, aluminum can be used for a wide variety of products. Because it does not rust, decay, or lose its quality, it can be recycled repeatedly without loss of properties.
We are aware of the importance of material flows throughout the economies of the world. We also recognize the need to make efficient use of all raw materials and natural assets consistent with resource-efficiency initiatives being developed by the European Union and others.
In conjunction with the International Aluminium Institute (IAI), we developed and update annually a materials flow analysis to improve understanding of global aluminum production; aluminum flows and inventories in customer and consumer products; and recycling loops.
For instance, statistical data entered into the model suggests that almost 75% of primary aluminum ever produced is still in productive use in transport, packaging, buildings, and other applications. For a more in-depth discussion, please read "Modelling More Sustainable Aluminum."
Global Aluminum Flow in 2011
In 2012, we continued to work with IAI, regional associates, Yale University, and the Norwegian University of Science and Technology to better understand current and future aluminum industry mass flows and ecological implications.
We believe that material flow can have financial, environmental, and social implications, and we continue our work to make all of our processes as efficient as possible.
Waste Materials Used
We use waste materials as raw materials in our processes where technically and economically feasible.
What is essentially a waste product from the petroleum refining industry—petroleum coke—we use as a raw material to form the anodes that are essential for our electrolytic process. We also purchase coal tar pitch, a by-product of the steel industry, as the binder for our anodes. We believe that these forms of “industrial ecology” are an important component of a sustainable business economy.
Recycled metal from products like used beverage cans, end-of-life vehicles, demolished buildings, and discarded consumer products continues to be an important source for our basic material, and its importance will keep growing. In 2012, we purchased and recycled 615,000 metric tons of aluminum scrap.
Please see the Recycling section for additional information.
Aluminum Metal Recovered from Purchased Scrap
Thousands of metric tons