Modelling of EAF Off-Gas Post Combustion in Dedusting Systems using CFD Methods

*Institute for Industrial Furnaces and Heat Engineering in Metallurgy, RWTH Aachen, Aachen/Germany; ** VAI-Fuchs GmbH, Willstatt/Ger-many To comply with the increasingly strict environmental regulations, the poisonous off-gas species, e. g. carbon monoxide (CO), produced in theelectric arc furnace (EAF) must be treated in the dedusting system. In this work, gas flow patterns of the off-gas post combustion in threedifferent dedusting system units were simulated with a computational fluid dynamics (CFD) code: (1) post combustion in a horizontal off-gasduct, (2) post combustion in a water cooled post combustion chamber without additional energy supply (no gas or air/oxygen injectors) and(3) post combustion in a post combustion chamber with additional energy input (gas, air injectors and ignition burner, case study of VAI-Fuchs GmbH).All computational results are illustrated with gas velocity, temperature distribution and chemical species concentration fields for the abovethree cases. In case 1, the effect of different false air volume flow rates at the gap between EAF elbow and exhaust gas duct on the exter-nal post combustion of the off-gas was investigated. For case 2, the computed temperature and chemical composition (CO, CO