Numerical simulation of the behavior of insulating particles in a free fall tribo-electrostatic separator with four vertical cylindrical electrodes

Abstract

This paper presents an analysis of the trajectories of tribocharged ABS and PVC particles in a free fall electrostatic separator. The installation that is the subject of this study is equipped with four vertical cylindrical electrodes. The behavior of the particles in this installation is compared with the one in a conventional configuration represented by two plate electrodes. The trajectory of the particles in both configurations is obtained by the numerical resolution of Newton's equation, which takes into account the magnitude and the direction of the electrostatic, gravitational and aerodynamic forces applied to the particles in the electrostatic separation zone. The calculation of the electrostatic force applied to the particles in this zone is performed using a numerical model of the electrostatic field obtained by finite element method implemented by means of the PDE-tool library of MATLAB software. The results of this study show that the use of a four-electrode configuration improves the quality of recovered products as it reduces the nuisible effect of the impacts between particles and electrodes observed in conventional plate-electrode installation. The use of the new configuration requires the development of a collector the shape of which should be adapted to the spatial distribution of the particles recovered at the outlet of the installation.