Development of a Mathematical Model to Follow Alumina Injection

To improve the operation of the aluminum reduction technology, each step of the alumina incorporation into the bath needs to be understood. The mathematical model presented in this paper, uses the Discrete Element Method (DEM), based on the description of the interactions between the particles and surrounding liquid, solving the kinematic equations. First, the description of particle-particle interactions was validated by experimental values of bulk density and angle of repose. Next, the interaction of particles with the liquid when arriving onto the free surface was added. Furthermore, modelling of phenomena like aggregate formation, breakup and dissolution requires the quantitative description and integration of further physicochemical knowledge. The number of injected powder particles during feeding is in the order of few hundred million. Following of such a number of particles is very much demanding computationally. Consequently, it is primordial to determine the minimal number of particles that reproduces correctly the physical reality.