CFD simulation of post combustion in the Electric Arc Furnace - Part I model development and application to flat bath

To obtain insight on the characteristics of the flow, combustion reactions, and heat transfer inside the EAF furnace, a three-dimensional CFD model was developed. Simulations of the process including the post combustion reactions, radiation heat transfer, and de-post combustion reactions have been conducted. Dissociation reactions of the post combustion products were also considered in the post combustion model. The predicted temperatures are realistic because of the inclusion of radiation and dissociation of CO2. Based on gas-liquid and gas/solid interfacial reaction kinetics, a de-post combustion reaction model was developed and successfully integrated in the CFD model to simulate the reactions between O-2 / CO2 and carbon in the liquid metal and the electrodes. It was found that the de-post combustion reactions decrease the net heat generated by reactions in the furnace and decrease the post combustion ratio. Oxidation rate of the electrodes was calculated. Radiation was found to be the main heat transfer mechanism from hot combustion gas to the metal and furnace wall. Under flat bath condition heat transfer efficiency is very poor; most of the heat generated by post combustion is transferred to the furnace wall.