Making sustainable steel through hydrogen plasma reduction of iron ores

Abstract

Steel is the backbone of the modern society. Although it is a key enabler of sustainability, its primary synthesis route is a heavy CO₂ emitter. With about 2.1 tons of CO₂ emitted per each ton of produced steel, ironmaking sector alone is responsible for ~7% of all CO₂ emission on the planet. This is because the current technologies to extract iron from its ores use carbon-carrier substances as a reducing agent, a fact that lead CO₂ as the by-product. To fight global warming, the most polluting sources must be tackled, especially the steel manufacturing sector.

Reduction of iron ores with hydrogen plasma may offer an attractive alternative to produce iron sustainably. In this route, a lean hydrogen plasma is ignited between the electrode of an electric arc furnace (EAF), slightly modified to support small partial pressures of hydrogen (e.g. 10%H₂), and the ore to be processed. During the process, both melting and reduction occurs simultaneously. This means that liquid iron is produced in one single step from its ores. In this talk, the fundamental aspects of the hydrogen plasma reduction (HPR) will be presented and discussed, with focus on the chemical evolution and phase transformations of the processed ores.

Bio

Isnaldi Souza’s background is in Materials Engineering. He defended his PhD in 2019 at the University of Sao Paulo (Brazil). His doctoral work was in the field of phase transformations in high Mn steels, and it had 1/3 of its activities developed at MPIE. He re-joined MPIE as a postdoctoral researcher in 2020 and became an Alexander von Humboldt fellow in 2021. In the same year, he became a group leader for the group Sustainable Synthesis of Materials.  His current research interests are, but not limited to, green steel, hydrogen-based reduction of iron ores, sustainable primary synthesis of metals.