Phénomènes électrostatiques dans les lits fluidisés et nouvelle méthode pour la mesure de la vitesse minimale de fluidisation dans les matériaux pulvérulents

We have used the electric current measure obtained from a porous electrode, to determine the minimal fluidization speed of a fluidized particles column. When gas speed (Ug) is inferior to the minimal fluidization speed (Umf), particles stay without motion. Increasing gas speed (Ug⩾Umf), the particles column initiates motion and a weak electric current appear caused by collisions of particles onto the electrode. To determine Umf we have applied the gradual depressurization method. Current is measured from the bottom electrode every depressurization step, variation of current allows to determine Umf. Results obtained are compared with some literature results from Richardson classical method.