The optimization of the process of aluminum remelting is of extreme importance to optimize and to increase the efficiency of the process of aluminum manufacture. However, the problem is highly complex, since the flow is turbulent, it involves high temperatures, implying that the phenomenon of radiation heat transfer is dominant and it also involves the combustion phenomenon. Besides the flow complexity, the number of variables that governs the phenomenon is very is high. The geometry of the furnace and the fuel to be used significantly influence the process. Besides those variables, the injection conditions of the oxidant also are extremely relevant for the evaluation of the efficiency of the combustion and cost of the process. The combustion process is strongly influenced by the choice between oxygen or air. In principle, the combustion with oxygen would be more efficient, however, air is more abundant and consequently cheaper, nevertheless it generates Nox, an additional pollutant, highly undesirable. Therefore, the choice of the injection condition is not trivial, it is necessary to analyze in detail the temperature distribution inside the furnace, the characteristics of the flame, the uniformity of the heat flow on the aluminum surface, as well as the water content. The present work presents a numerical simulation employing the commercial software FLUENT, and the reactions of the liquid fuel with both air and oxygen are investigated.