Aluminum recycling is the process through which scrap aluminum is reprocessed to be used in products after its initial production. Aluminum producers and recyclers in the aluminum industry work with individuals, businesses, and communities to enable both curbside and industrial recycling programs. For most aluminum products, the metal is not consumed during the products lifetime, but it is simply used making it easy to recycle without losing its intrinsic properties. Used beverage container (UBC) recycling is the most recognized of the aluminum recycling programs. However, end of life recycling of certain products like building parts and cars allows for the production of recycled materials like window frames, wire, tubing and electronic parts.
Process of Aluminum Recycling
The following is step by step process of aluminum recycling:
1. Collection of Scrap Aluminum
Drinks cans, aluminum foil trays, and aerosol cans are collected from homes, streets and garbage collection centres by hired individuals or business people who major in aluminum collection. They are sometimes mixed with steel cans. The scrap aluminum is then collected together and then it is transported to the treatment plant.
The mixed metals (aluminum and steel cans) are taken to a materials recovery facility where they are cleaned, sorted into different metal streams and later compressed into bales. This step is very important in ensuring that the aluminum is separated from other metals. It is important to point out that drink cans and certain food cans are made out of steel.
The aluminum blocks bales are later transported to a processing plant. The blocks are then put onto a conveyor that transports them to the shredder. The shredder then cuts the cans into tiny pieces. This is done to make it easier to get rid of all the paintings and coatings that are used for decoration and protection purposes. Additionally, it makes it easier for the metal to melt quickly in the furnace.
4. The Shredded Cans are Passed Beneath a Powerful Magnet
This process aims at completely eliminating traces of steel. Since steel is magnetic, it is easy to separate it from aluminum once it is passed under a magnet. This ensures that the recycled aluminum contains no steel and meets the quality standards set.
The aluminum shreds then are taken by the conveyor system into a specialized decoater. This is where all the decorations are detached from the shredded pieces. The decoater then blows very hot air through the tiny pieces of shreds and the coatings, paintings and inks vaporize. The hot gases are then removed and cleaned.
6. The Decoated Shreds Are Then Fed Into the Furnace
Traditionally, the furnace is heated up to 7000C; this is the lowest melting point for certain metals. During this process of melting, certain chemicals are added into the molten aluminum to make it have the correct composition. All the impurities will then float to the top surface of the hot aluminum. This forms a layer called dross. The dross is then removed using a specialized scraping tool.
7. The Holding Furnace
The holding furnace is basically where the molten aluminum is transferred to. It is also known as the holding furnace. This is where the aluminum waits to be turned into ingots. From time to time, the holding furnace tilts to pour the molten aluminum into moulds. Each ingot or block contains approximately 1.6 million drink cans.
8. Transportation of the Ingots
The finished ingots are then lifted by an overhead careen from the casting pit. The ingots are then loaded onto queue waiting track to be transported and dispatched to the rolling mill. The ingots are then rolled out making thin sheets of aluminum. This gives the metal greater strength and flexibility. The sheets of metal are then collected and used by the packaging factories to make drink cans, foils and other useful products. Then the process begins once again. In a span of as a little as six weeks, the recycled aluminum products are sent back to the shelves in the shops and supermarkets ready for usage.
Advantages of Aluminum Recycling
Aluminum recycling is a common practice that has been around since the early 1900s. It is a very important process because of the numerous advantages as can be seen below:
1. Saves Energy
Used beverage containers are among the largest components of aluminum scrap. Most of the scrap metal is recycled back into cans. The other largest user of the recycled aluminum is the automotive industry. According to the Aluminum Association President, Mr. Steve Larkin, recycling of old aluminum cans into new ones requires less energy (95%) than producing new ones from the scratch. He states that the recycling process also produces 95% reduced greenhouse gas emissions than entirely making new cans.
2. Prevents Depletion of a Valuable Commodity
Aluminum is a metal that is mined from the earth’s crust as Bauxite ore. This therefore means that, recycling prevents continuous mining and depletion of this valuable commodity. Each year, recycling prevents approximately five percent of the total Bauxite ore mining in the world.
3. Reduction of the Carbon Footprint
Increased environmental awareness and the need for social responsibility have led to the increased aluminum recycling among many countries and companies today. Did you know that recycling aluminum helps in preventing more than approximately 90,000,000 tons of toxic carbon dioxide from being let free into the air every year? Yes, recycling a single drink can made of aluminum prevents carbon dioxide emission that equals a single mile car ride and it saves adequate energy to power a typical television set for about two to three hours. Today, every country has the responsibility to do whatever it can to reduce carbon emission. This means that if all countries focus on the reduction of carbon dioxide emissions there will be little concern about global warming.
4. Helps in Satisfying the Increasing Demand
As the population increases so does the need for aluminum products. Today, aluminum has more uses and applications other metals. This means that there should be a continuous production of this metal so as to meet the increasing demand. Mining alone is not sufficient enough to meet this demand. Recycling therefore comes in to bridge the gap. In fact half of the aluminum cans are recycled. Manufacturers today use approximately 35 percent of the recycled aluminum and approximately 65 percent of the natural aluminum to meet up their manufacturing needs. Therefore, it is necessary to recycle aluminum.
5. It Never Wears Out
Aluminum is infinitely recyclable. This means that it can be recycled over and over without necessarily losing its natural qualities. It is because of this fact that most manufacturing companies are resorting to use aluminum in most of their products. The metal is light weight, versatile and can be used in a number of applications.
6. Reduction of Landfill
Waste management is becoming a big problem in today’s economies. Solid waste management is in fact one of the biggest problems facing many countries in the world today. Most countries dig up huge holes in the ground for burying waste. By recycling aluminum, the space that would be needed for burying the aluminum waste is saved and can be used for other purposes.
In summary, aluminum recycling is important to the environment and the people all over the world. It is essential for all world economies to embrace recycling of solid waste and reduce carbon dioxide emission.
Image credit: Mojave Desert
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