EAF dust is shipped to one of our four Waelz kiln recycling facilities, where valuable metals are reclaimed as Waelz Oxide product, more commonly known as WOX.
At our recycling facilities, EAF dust is fed along with coke or coal into a Waelz kiln, which is a large, rotating metal tube. In the kiln the EAF dust is tumbled and heated to a temperature where certain non-ferrous metals are vaporized. Air is drawn through the kiln and the metal vapors are oxidized to form solid metal oxide particulates which, once collected, is WOX. Air from the kiln passes through a product collector where the WOX is gathered. WOX is a light gray metal oxide powder, that contains 60% zinc oxide. Other metal oxides recovered in WOX include lead oxides, cadmium oxides, and chromium oxides.
The remaining portion of EAF dust that exits the kiln is Iron-Rich Material, referred to as IRM. IRM contains 40% iron oxide and other minerals, and once tested to ensure hazardous metals have been removed, can be sold to asphalt, cement, or aggregate companies, and it can even go back into the steel production process.
WOX is a product that is shipped to the company-owned Zinc Products facility, or it can be sold to other zinc metal producers as feedstock for zinc metal production.