Nitrogen Injection in Molten Aluminum in a Tank Degasser

Abstract

The injection of nitrogen in molten aluminum through a static impeller in a tank degassing unit is studied. Using basic principles of fluid mechanics, it is analyzed the influence of the nozzle diameter on the bubble diameter and the mean residence time of the bubbles in the molten aluminum. By means of transient isothermal 2D Computational Fluid Dynamics (CFD) simulations, the influence of the nitrogen volumetric flow rate on the phase distributions and the tank degasser dynamics is studied. Finally, an adiabatic CFD simulation is carried out in order to elucidate the changes in the molten aluminum temperature due to the injection of nitrogen at ambient temperature. This simulation shows that molten aluminum does not suffer drastic temperature reductions given that, in spite that the nitrogen is fed at ambient temperature, the mass of nitrogen is relatively small compared with the mass of aluminum.

Preparation of Rotor Geometry for Setting up Numerical Model of Flow in Refining Ladle

“…The refining ladle was replaced by a container of a similar volume but made of a material allowing for monitoring the phenomena inside the refining ladle. fields during the refining, but also the refining process itself [11][12][13][14][15][16][17][18][19]. The CFD m also one of the options to verify whether the wear process of the rotor has a neg positive impact on degassing efficiency, or to perform the optimization of the r peller shape itself.…”

“…Proc. 2024, 60, 13 2 of 6 fields during the refining, but also the refining process itself [11][12][13][14][15][16][17][18][19]. The CFD method is also one of the options to verify whether the wear process of the rotor has a negative or a positive impact on degassing efficiency, or to perform the optimization of the rotary impeller shape itself.…”

“…One approach to simulation of the refining process is to use numerical methods. The Computational Fluid Dynamics (CFD) method can describe not only the flow and pressure fields during the refining, but also the refining process itself [11][12][13][14][15][16][17][18][19]. The CFD method is also one of the options to verify whether the wear process of the rotor has a negative Eng.…”