By-products from the Metallurgical Industry – Case Study: Slags from Primary Lead Production
Developments in the supply of raw materials are characterized by decreasing metal grades and still relatively low recycling rates. While the recycling of metallic scrap is nowadays state-of-the-art, metal-containing by-products from the metallurgical industry represent a new potential secondary resource. Typical by-products such as slags, sludge or dust become more and more important because such residues carry significant amounts of valuables. Due to the lack of efficient technologies and an accepted guideline for the assessment of landfilled material, this potential often lies idle. Through special characterization of selected residues and the evaluation of possible recycling processes, a generally valid assessment scheme should be possible and provide interested investors and companies with a reliable information on potentially usable secondary resources. This presentation describes a government-funded project at Montanuniversitaet Leoben, Austria, that involves seven international companies. An evaluation system followed by a certification step is beneficial for both continuously produced metallurgical by-products and landfilled materials from the past. These resources will be submitted to recycling step-by-step, thereby offering new potentials that enlarge the present metal resource base. A case study for slags from the primary lead industry gives an insight into the ongoing research and development. In parallel to the evaluation of different slags, two strategies for the treatment have been developed. Whereas one of them focuses mainly on the contained metals, the other tries to realize a zero-waste strategy when processing slag components. The results for both strategies are presented and discussed from a technological, as well as an economical, point of view.
Jürgen Antrekowitsch was awarded a doctorate from the University of Leoben in 2004. Remaining at the University, in 2010 he became an Associate Professor at the Chair of Nonferrous Metallurgy and between 2011 and 2018 served as the Director of the Christian Doppler Laboratory for Optimization in Heavy Metal Recycling. Currently, Jürgen is responsible for the ’Assessment of metal-bearing by-products’ research unit.