NOx Prediction of Supersonic Coherent Jets for Electric Arc Steelmaking Furnace

Abstract

Supersonic coherent jets are widely in practice in steelmaking processes including electric arc furnaces (EAF). Injecting oxygen through such coherent jets plays a vital role in enhancing the liquid gas mixing and reaction rates leading to boosting energy efficiency. Several experiments and numerical simulations have been carried out to understand the physical phenomenon of the coherent jets and to predict the behavior of the jets. However, the research on pollutant formation in the coherent jets for steelmaking is limited. As the industry transitions toward reducing emissions, prediction of pollutant formation is crucial. This numerical study analyzes both methane shrouding coherent jets and hydrogen shrouding coherent jets and predicts the NO_x (oxides of nitrogen) formation. It has been found that NO concentration dominates over N₂O and NO₂ and has the highest concentration around the jet. Although the NO concentration reaches as high as 1070 ppm at high-temperature region around the jet, it remains below 225 ppm along the fuel inlet axis. Also, it has found that the NO_x concentrations increase along the radial direction up to \(1.5{\text{De}}\) from the jet central line and gradually decreases, whereas the NO concentration peaks at \(15{\text{D}}_{{\text{e}}}\) along the jet axis in the downstream direction.