Factors that influence the trajectories of charged insulating particles in roll-type electrostatic separators

The electrostatic separation is known as an efficient and robust recycling technology, characterized by low cost, reduced energy consumption and ease of use. However, the separation process is multifactorial and requires a judicious choice of electrical and geometrical parameters in order to enable the processing of different material mixtures and obtain an optimal result. The aim of this paper was to study the different factors that influence the trajectories of charged insulating particles exposed to an intense DC electric field of a roll-type electrostatic separator. For this purpose, a numerical model, based on the fundamental principles of dynamics, was elaborated in order to simulate the behavior of the particles in such electrostatic devices. The numerical model considered the main electrical, mechanical, and aero-dynamical forces that govern the movement of the particles. To check the accuracy of the numerical model, several experiments were carried out on charged insulating particles in the roll-type electrostatic separator. The particle trajectories were recorded with a high-speed camera and compared with those obtained by numerical simulation. The results obtained validate the numerical model, as the simulated trajectories were similar to those captured by the camera.