Valorisation of Recovered Biomass into Biochar as a Reducing Agent for Electric Arc Furnaces

The steel industry relies heavily on fossil carbon sources, particularly anthracite, to sustain the reducing reactions required in electric arc furnaces (EAF). This dependence leads to significant scope 1 greenhouse gas emissions and limits progress toward industrial decarbonisation.

This research investigates a sustainable alternative by transforming residual wood biomass—originating from steel industry waste streams—into high‑performance biochar suitable for partial substitution of anthracite in EAF operations.

The project develops and validates an integrated process based on controlled pyrolysis of lignocellulosic residues, aiming to obtain a carbon‑rich solid with physicochemical characteristics compatible with EAF metallurgical requirements. A systematic experimental programme is implemented to characterize raw biomass, optimise pyrolysis parameters, and analyse the resulting biochar through X‑ray diffraction, elemental analysis, thermogravimetry, calorific value assessment, and surface area measurements.

Laboratory‑scale melting trials in an induction furnace are carried out to evaluate the biochar’s reducing capacity and its impact on steel quality. The study also includes a life cycle assessment comparing different waste streams and the environmental performance of the biochar system with a fossil‑based reference scenario.
Results indicate that appropriate combinations of synthesis conditions and biomass composition yield biochars whose carbon content and reactivity approach that of commercial anthracite, while valorising internal waste streams.

This approach supports circular‑economy strategies, establishes the basis for industrial scaling, and demonstrates a promising pathway toward low‑carbon metallurgical processes through renewable carbon sourcing, improved resource efficiency, and reduced dependency on fossil materials.