Modélisation Du Fonctionnement D’un Séparateur Tribo-Aero-Électrostatique Pour Matériaux Plastiques Granulaires

Abstract

Numerical simulation has proved to be a powerful tool in the research and development of new electrostatic processes. In this work has been introduced a simple mathematical model for simulating the outcome of a tribo-aero-electrostatic separation process for binary mixtures of granular materials. The mathematical model assumed that the probability of a granule to be separated can be expressed as a function of the number of impacts with granules belonging to the other class of materials. The process is characterized by the fact that the charging of the granules is produced in a fluidized bed device, in the presence of an electric field. The aim of this study is to simulate the continuous operation of such a device at various feed rates. The evolution in time of the mass of granules collected at the electrodes has been computed for various compositions of the granular mixture. The effect of the walls and the presence of a third species of particles were taken into account. The computed results were in good agreement with the experiments. They demonstrate that open-loop continuous operation of the separator is possible for a range of feed-rates that depends on the composition of the materials to be separated.