Ehab Tara

COMET-Project: CO2 Neutral Zero Waste Solution for Zinc Recycling – Green Zinc

Zinc is one of the most important metals in human society. Especially its application as corrosion protection of steel makes it an omnipresent element in daily life showing an increasing demand in
future. In addition to corrosion protection other important
applications of zinc can be found in the rubber-, ceramics- and fertilizer industry, and in different casting products, pharmaceuticals and nutritional supplements. The European zinc demand ranges from 2.4 to 2.7 Mio. tons/a. Unfortunately, Europe is weak in primary zinc resources. Only a small part of approximately 27 % can be supplied by European mines. As a result, the dependency on imports from Asia and South America is quite high. Furthermore, zinc concentrates show strongly decreasing zinc values with a rising iron contamination. This contaminant leads to problems by generating huge amounts of residues which are difficult to dump. One way out of this situation is to utilize zinc from end-of-life products. Nevertheless, the remelting of such scraps only contributes to about 6 %. However, due to its volatile character, zinc is often found as oxide in the dust of steel recycling facilities. Furthermore, slags from the lead industry also present interesting amounts of zinc. Such by-products have the potential to contribute much more to the European demand. Taking high zinc containing dust from the steel industry and slags from the lead industry into account, about 20 % of the demand could easily be covered. Unfortunately, present technologies show essential disadvantages which start to become a big obstacle for future metal recovery efforts such as:
• Only zinc is recovered, even though further metals like iron and lead are available.
• Huge amounts of new residues, up to 80 % of the input material, are generated.
• Currently applied processes are based on reduction with fossil carbon carriers resulting in a significant carbon footprint.
The overall aim of the project is to stabilize or increase the zinc recovery from the by-products steel mill dust and lead slag in future by making potential technologies “green”. This includes the minimization of the CO2-footprint by replacing the fossil reducing agent and the optimization of the remaining slag in a way that makes it suitable for the building and construction industry. The final results are sustainable short- to mid-term and long-term concepts that allow Austria and Europe to utilize these potential zinc resources, meeting the environmental requirements of the future.

Tara E., Wiessler T., Hanke G., Antrekowitsch J.: Non-Ferrous Slags in the Circular Economy: Sustainable Valorization of Heavy-Metal-Containing Slags.. Springer World Sustainability Book Series., 2026.

Tara E.: Green Zinc: CO₂ Neutral Zero-Waste Solution for Zinc Recycling. 1. MU Leoben-TU Freiberg – Seminar, České Budějovice, Tschechien, 2025

Tara E.: Optimization of Recycling Slag with Focus on Lead and Zinc Metallurgy. 17th Global Slag Conference 2025, Wien, Österreich, 2025

Tara E.: Green Zinc: CO₂-neutrale Zero-Waste-Lösung für das Zinkrecycling. MU Leoben-TU Aachen – Seminar, Coburg, Deutschland, 2025

Tara E.: Non-Ferrous Slags in the Circular Economy: Sustainable Valorization of Heavy-Metal-Containing Slags. 4th International Conference on Responsible Consumption and Production, Chania, Crete, 2025

Tara E.: Advances in Slag Utilisation for Sustainable Lead and Zinc Metallurgy. Workshop der Nichteisenmetallurgie 2025, Weiz, Österreich, 2025

Tara E.: Integrated Multi-Modal, Multi-Scale Characterization of Complex Slag Systems, Exzellenzclusters: Recycling 2025, Leoben, Österreich, 2025

Tara E.: Slag-to-Sand: Manufacturing Sand-Like Granulates from Metallurgical Slags, Exzellenzclusters: Recycling 2025, Leoben, Österreich, 2025