Modelling the Thermal Treatment and Expansion of Mineral Microspheres (Perlite) in Electric Furnace Through Computational Fluid Dynamics (CFD): Effect of Process Conditions and Feed Characteristics

A model-based investigation of the interplay between furnace setup and spatio-temporal evolution of particles' state variables is also presented. The effect of feed size distribution and processing of ultrafine ore are discussed. The process is controlled primarily by the wall temperature and secondarily the air feeding rate; an increase of furnace wall temperature from 900 to 1200 degrees C reduced the final density to 484, 979, and 1262 kg/m(3) for feed size of 150 mu m, 250 mu m, and 350 mu m. Model predictions are in good agreement with the experimental measurements possessing differences below 10% in most cases.