Einsatzmöglichkeiten von Biomasse als Reduktionsmittel in metallurgischen Recyclingprozessen

Translated title of the contribution: Application of biomass as reducing agent in metallurgical recycling processes

Thomas Michael Griessacher

Research output: ThesisDoctoral Thesis


The present PhD thesis studies the substitution potential of fossil carbonaceous materials with alternative, carbon-neutral, on biomass based reducing agents in metallurgical recycling processes. In that case high-quality charcoal is produced and tested concerning its applicability in selected processes. Therefore the influence of the process parameters on the charcoal quality and quantity, with special focus on the physical properties like reactivity and specific surface area, were investigated. With these optimal parameters, which guarantee the production of a charcoal, which meets the metallurgical requirements, their application potential in two different operations was examined. For the first observed process, the Waelz process, the high reduction efficiency of charcoal was demonstrated in lab-scale as well as in industrial trials. Hereby no negative effects on the process itself as consequence from the substitution of petroleum coke by charcoal could be recognized. The zinc and the lead yield as well as the energy balance of the Waelz kiln remained constant. Also no accretion formations resulting from the introduced charcoal ash could be observed. The second determined case for the application of charcoal in the recycling of metals was the injection into the slag of electric arc furnaces. Experiments in the lab as well as in industry showed the complete non-wettability of charcoal in comparison to petroleum coke, which is normally used. This fact prevents the reaction between the carbonaceous material and the FeO in the slag and therefore the slag foaming by CO-bubbles. This leads to the conclusions, that in this special field carbon-neutral injection coals, like charcoal, can hardly be used. Beside the utilization of charcoal also some investigations concerning the applicability of the by-product of the carbonization process, the pyrolysis gas, as reduction gas in the recycling of heavy metal-containing residues in a retort were done. The experimental tests once again delivered very promising results and demonstrated the high reduction power of the pyrolysis gas.
Translated title of the contributionApplication of biomass as reducing agent in metallurgical recycling processes
Original languageGerman
  • Antrekowitsch, Helmut, Assessor A (internal)
  • Friedrich, Bernd, Assessor B (external), External person
  • Antrekowitsch, Jürgen, Supervisor (internal)
Publication statusPublished - 2012

Bibliographical note

no embargo


  • biomass
  • charcoal
  • reducing agent
  • metal recycling

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