A common question in the recycling industry is about the separation of copper and aluminum and how it is possible. The reason is because of their different densities, however, achieving this separation is not always straightforward, and here is why:

Imagine an air table, with an opening on top for material intake. The setup includes a vibrating deck, often referred to as a fluidized bed, and an airbox below the screen deck which pressurizes air upwards. As the deck vibrates, in a vertical circular motion, lighter particles, like plastic, tend to float above, while heavier copper particles settle lower because of their weight. This principle applies similarly to aluminum and copper mixtures, such as those found in aluminum-copper radiators.

In such cases, both metals are fed onto the table. Copper, being denser, settles to the bottom of the vibrating deck, climbing upwards because of its friction on the screen and by the motion of the deck. Meanwhile, aluminum, less dense and typically in flake form, tends to float and exit from the back of the table.

To optimize this process, especially in larger plants, multiple stages of separation are used. Initial stages yield a mix of metals, where aluminum nuggets or tightly bound aluminum-copper pieces will contain both metals. These materials can undergo further processing, such as granulation, to liberate and refine the metals. When returned to the air table, the deck predominantly captures copper due to its higher concentration, leaving residual aluminum to exit later.

Efficiency in separation improves with the higher concentration of one metal over the other. A balanced mix results in an even distribution across the table, whereas a higher concentration of copper shifts the distribution towards the back, where the remaining aluminum will sit and tumble off.

In larger systems, these processes are continuous and integrated. Smaller setups, constrained by space or capital, may store mixed materials for later reprocessing. While some may prioritize separating copper due to its higher market value, our method focuses on achieving cleaner aluminum outputs initially, reducing the need for extensive reprocessing.

Additionally, prior to separation, we employ screening to remove contaminants like lint, dust, and residual oils from materials like radiators or A/C coils. These contaminants, often trapped during shredding, can impact processing efficiency by clogging screens.

For further insights or questions, please reach out to us!