The Influence of Oxygen Injection Configuration in the Performance of an Aluminum Melting Furnace

Abstract

In the present work, a numerical simulation of the 100% oxy-firing combustion process inside an industrial Aluminum Remelting Reverb Furnace is presented. A staged combustion oxy-fuel burner is being simulated. The natural gas and oxygen were injected toward the aluminum bath, which was considered as an isotherm wall at melt temperature. Two types of burners are compared. For the first case, the oxygen and natural gas jets at the burner exit are parallel to each other, while for the second burner, a divergent oxygen jet is employed. The furnace heat loss to the ambient is neglected since it is small in relation to the heat liberated by the combustion process. The k-ε model of turbulence was selected to represent the turbulent flow field. The combustion process was determined based on the Arrhenius and Magnussen Laws, and the discrete transfer radiation model was employed to predict the radiation heat transfer. The numerical procedure was based on the Finite Volume Method. This numerical model is utilized to determine the flame pattern, species concentration distribution, and the velocity field. The temperature distribution is very useful in the evaluation of the furnace performance. Further, critical regions associated with high temperature spots at the refractory surface were discovered. The effect of the divergent jet in the heat flux distribution at the aluminum bath is also investigated.