Treatment of Residues from the Copper Industry with an Alternative Approach for Electric Furnace Slag
Treatment of Residues from the Copper Industry with an Alternative Approach for Electric Furnace Slag
Stephan R. Steinacker 0 1 2
Juergen Antrekowitsch 0 1 2
0 Schlüsselwörter: Recycling von Kupfer , Reststoffe, Kupferschlacke, Roheisen, Reduktion
1 S. R. Steinacker ( ) Christian Doppler Laboratory for Optimization and Biomass Utilization in the Recycling of Heavy Metals, Chair of Non-Ferrous Metallurgy , Montanuniversitaet Leoben, Franz-Josef-Strasse 18, 8700 Leoben , Austria
2 Christian Doppler Laboratory for Optimization and Biomass Utilization in the Recycling of Heavy Metals, Chair of Non-Ferrous Metallurgy , Montanuniversitaet Leoben, Leoben , Austria
Today's copper industry sees itself confronted with a variety of different residues and by-products. This situation can be explained by the decreasing content of copper in the primary ore concentrate and the multitude of further downstream processes and applications. This work aims at giving an overview of the different residues that derive from the primary as well as the secondary copper industry and highlights the potential in eastern and southeastern Europe. The core part of this article describes different recycling and recovery methods, which can be split into two main categories. The direct treatment generally consists of a remelting step which builds on a detailed chemical analysis and aims at the preservation of the contained alloying elements. In contrast to the direct option, the conventional recycling consists of several process steps which gradually increase the purity and quality of the material. The description of a new approach for the treatment of electric furnace slag concludes the considerations concerning the different residues. While the introduction of primary copper smelting slag into an electric furnace displays a commonly applied procedure which leads to a marketable product, legislative as well as environmental restrictions may restrict this opportunity in the near future. As a result, a pyrometallurgical approach that uses pig iron as a reducing agent aims at lowering the contained heavy metal content in the slag and hence at guaranteeing the required marketability.
Copper recycling; Residues; Copper slag; Pig iron; Reduction
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Zusammenfassung: Die heutige Kupferindustrie sieht sich
mit einer Vielzahl an unterschiedlichen Reststoffen und
Nebenprodukten konfrontiert. Diese Tatsache lässt sich vor
allem auf den abnehmenden Kupfergehalt im Erzkontentrat
und die Verschiedenartigkeit der weiterverarbeitenden
Prozesse zurückführen.
Ein Ziel der vorliegenden Arbeit liegt darin,
unterschiedliche Reststoffe aus der primären und sekundären
Kupferindustrie näher zu beschreiben, wobei ein Fokus auf dem
vorhandenen Potenzial im ost- und südosteuropäischen Raum
liegt. Die direkte Aufarbeitung besteht grundsätzlich aus
einem Aufschmelzschritt, welcher eine genaue chemische
Analyse verlangt und auf einen möglichst geringen Verlust
der vorhandenen Legierungselemente abzielt. Im
Gegensatz dazu umfasst das konventionelle Recycling eine breite
Prozesskette, über welche die Qualität und die Reinheit des
Werkstoffs kontinuierlich zunehmen.
Abschließend soll eine alternative Methode für die
Aufarbeitung von Schlacke aus dem Elektroofen beschrieben
werden. Während der Einsatz von primärer Kupferschlacke
in diesem Aggregat einen klassischen Prozess zur
Kupferrückgewinnung darstellt, welcher darüber hinaus zu einem
absatzfähigen Produkt führt, könnten legislative sowie
umwelttechnische Restriktionen zu einem abrupten Ende der
bewussten Nutzung führen. Der in dieser Arbeit
beschriebene pyrometallurgische Ansatz versucht, den
Schwermetallgehalt der Schlacke weiter zu senken, um so deren
Marktfähigkeit weiterhin zu gewährleisten.
1. Introduction
After iron and aluminum, copper represents the third-most
produced metal on a global basis with an annual amount
of around 21.1 Mio. t considering the copper content of the
world mine production in the year 2015 [1]. While the
primary production from sulfidic and oxidic ores still
represents the central production route, recycling methods
constantly gain importance. In addition to the valuable metal
copper, residues and by-products display a broad variety
of chemical elements which can improve the economic
feasibility of different secondary processes [2].
This work concentrates on copper companies and
sources from eastern and southeastern Europe (ESEE).
After giving an overview of the potential in this region,
different residues from the copper industry can be
investigated. Subsequently, adequate recycling techniques are
presented, which lead to a classification into direct as
well as conventional approaches. Their common goal is
represented by an efficient recovery of copper and the
production of a high-purity material. In addition, by-elements,
such as zinc, lead, and arsenic, are also considered. On the
one hand, these display a contamination within the raw
material, while, on the other hand, their r (...truncated)