Until now the only way of treating Zorba for the removal of contaminants such as magnesium has been a two-stage sink-float operation whereby the majority of the heavy metals are separated from the shredder scrap, while the hollow aluminum scrap, magnesium and high-density plastics are floated out in an additional media stage. Sink-float processes have historically been difficult to manage, require a large footprint, can be relatively unstable and can be expensive because the operational cost per ton is relatively high.
Now, TOMRA’s upgraded X-TRACT for magnesium removal offers a reliable, robust and cost-effective alternative to sink-float separation. The system uses existing TOMRA XRT technology but in a new configuration so that it is capable of sorting material of different density levels and separates magnesium from aluminum to create furnace ready products, including low magnesium Twitch, across the Zorba size spectrum from 5-120mm.
This degree of separation of fines simply could not be achieved using dense media plant technology/ sink-float separation process. And, until now, it wouldn’t even have been possible using TOMRA’s sensor-based sorting technology because magnesium is very similar in density to aluminum so the technology couldn’t recognize the difference between the materials. Now, the capabilities and combination of the x-ray technology used in our X-TRACT makes it by far the most consistently accurate solution to date.