Aluminium is probably the easiest material to recycle. Recycling aluminium is even easier than recycling glass! The whole process basically implies just re-melting the metal. It can then be further used to manufacture new products. Recycling is, therefore, much less energy-consuming than creating new material from scratch.
Creating new aluminium requires conducting a process called electrolysis of aluminium oxide (Al2O3). Electrolysis uses electricity to catalyze chemical reactions that would not happen under normal conditions. Apart from that, someone first has to refine aluminium oxide from the natural material – bauxite. Bauxite, which is the most important ore of aluminium, only contains from 30% to 60% of it. The whole procedure is rather cumbersome and expensive. On the other hand, recycling aluminium requires only 5% of the energy used to make it from the raw ore. For this reason not only conscious consumers, but also profit-oriented corporations are trying their best to enforce separate collection of aluminium and its consequent recycling.
History
Due to the advantages presented above, aluminium recycling is one of the oldest recycling practices. The first attempts to recycle this metal appeared as early as in the 1900’s. The practice became even more wide-spread during World War II. However, recycling reached its peak popularity in 1960’s, when beverage cans appeared on the counters. Up to this day, cans for various drinks are the most popular usage of aluminium. Consequently, they are also the most recycled.
Just like glass, aluminium does not deteriorate during recycling, therefore, it can be recycled indefinitely. The quality of the recycled product will not be any worse than that of the initial product. Therefore, recycled metal has the same usage as the newly manufactured one: beverage cans, bicycle tires, computers, kitchen ware and many other products which require a light strong material. Moreover, aluminium is a key component of some computer hardware and various types of wiring, due to its high thermal conductivity.
Aluminium recycling process
As with any other recycling process, the first stage of it is a consumer throwing his beverage can or chocolate foil into a recycling bin. On the next stage that aluminium is collected and taken to a recycling plant, where it is cleaned and sorted. Special machines usually cut beverage cans into small pieces. This helps to decrease the volume they occupy, and also makes it easier for separating machines.Usually cleaning the metal from inks and admixtures happens during the melting stage, however, some products require additional cleaning.
At the next stage the pieces turn into aluminium blocks. This helps to prevent oxidation during the melting stage, as aluminium easily turns back into its oxide, when exposed to oxygen. The resulting blocks then undergo spectroscopic analysis. As a result of this analysis and according to the desired goal admixtures like copper or zinc may find their way into the mixture. Only at this stage the substance proceeds into the furnace, where it finally melts.In case of beverage cans the melted mass turns into big blocks – ingots – each consisting of approximately 2 million cans. Special machines subsequently roll the ingots out, giving them additional flexibility and strength. The obtained aluminium sheets are ready for creating new drink cans, food packaging and, most importantly, chocolate wrapping!