Current EAF Dust recycling is dominated by third party companies using the Waelz Process - a high-temperature metals recovery process (HTMR) - designated by the EPA as the BEST Demonstrated Available Technology (BDAT) for EAF Dust Management.
Despite BDAT designation the Waelz Kiln Process route:
- produces high greenhouse gas emissions.
- produces lead, mercury and particulate emissions.
- does not recovery heavy metals - producing a low value, low-grade iron-rich clinker used as aggregate.
- produces an initial low grade Crude Zinc Oxide (CZO) which requires additional refining.
- requires large CAPEX to achieve SHG Zinc and Zinc Oxide products > US$ 200M.
The Waelz Process closes the EAF Dust recycling route - but as a stand alone facility - necessitating significant logistics transporting EAF Dust to the processing site.
The coal-based Waelz Process is energy intensive and unable to harness synergies associated with EAF off-gas heat recuperation.