Contribution Oral Presentation
Sustainable Steelmaking – Carbon free steelmaking by Hydrogen Plasma Smelting Reduction
- Mr. Alexander RIMSER
- Mr. Alexander RIMSER (K1-MET GmbH)
The climate change, mainly caused by gaseous emissions like CO2, is globally one of the most important subjects. Big efforts are required to solve this problem within the next decades. The European Commission´s low carbon roadmap suggests a reduction of CO2 emissions of 80 % by 2050 compared to 2005 levels. The steel industry, which contributes around 6 % to the worldwide anthropogenic emissions of CO2, is asked to decrease the greenhouse gas emissions.
There are two possibilities to perform low-C economy: Carbon Direct Avoidance (CDA) and Smart Carbon Usage (SCU). In the case of CDA no carbon is being used for iron ore reduction processes. In the case of SCU process integration with reduced carbon input and carbon capture and usage are being performed.
In this paper the CDA path using hydrogen as reducing agent for iron ore will be presented. In a couple of doctor theses on laboratory investigations at the Montanuniversitaet Leoben/Austria since the 1980´s it has been shown that hydrogen – especially in the plasma state – is an excellent reducing agent for iron oxides. Based on the results of these investigations and on actually running laboratory work it has been decided by a consortium of scientific and industrial partners to go a step ahead and to build a bench scale plant for HPRS (Hydrogen Plasma Smelting Reduction). The upscaling from the laboratory to bench scale is in a range from 100 g to 100 kg of iron ore.
In this bench scale plant, which is located at the Donawitz site of voestalpine, smelting reduction tests using hydrogen in gas mixtures are being carried out. A transferred plasma arc will reduce and melt down fine grained iron ore in one step. The ore is fed into the plasma arc through a hollow electrode. Main first objectives are a stable process concerning the plasma arc and the continuous feeding, melting and reduction of the iron ore to liquid metal. Results of trials with different plasma gas compositions and different feed materials will be shown.