Computational Fluid Dynamic‐Discrete Element Method Study of Biocarbon Injection in Electric Arc Furnaces Using Shrouding Jet Injectors

The steel manufacturing industry's push for decarbonization has led to interest in using biomass‐derived carbon (biocarbon) in electric arc furnaces (EAF), which typically rely on fossil‐based carbon. Supersonic air injectors deliver carbon particles at high speed through the freeboard to penetrate the EAF slag layer. This study compares the behavior of denser fossil‐derived carbon particles (density 800 kg m − 3 ) with lighter biocarbon particles (density 200 kg m − 3 ) when they are injected using a supersonic lance. While lighter particles reach higher peak velocities, they decelerate rapidly, especially at greater distances from the lance. This limits the injection range for the lighter particles. Potential mitigation strategies are examined. No significant advantage from coinjecting denser and lighter particles together is found, as it causes significant particle dispersion away from the injection axis. Lengthening the lance's mixing zone, where the particles interact with the supersonic airflow, provides only modest improvement in particle velocity and reduction in particle dispersion. Increasing the size of the particles, however, enables the biocarbon particles to maintain their speed for a longer distance. It is concluded that using larger particles and/or adjusting the lance position closer to the slag layer is likely needed for effective biocarbon injection.