Design and Analysis of an Eddy Current Metal Separator in a Single Stream Solid Waste Management System

Abstract

Recovery and recycling of metal items from waste sources is very important in economic and environmental aspects. The purpose of this study is to design and simulate and eddy-current metal separator which is used industrially in waste sorting plants, usually for separating the non-ferrous metal particles from other wastes. In this process repelling forces act on non-ferrous metals. The force is dependent upon the magnetic flux created by the eddy current and also on the dimensions and electric conductivity of the particles. To achieve this permanentmagnet are used. Because of the force, metal particles are thrown at a trajectory from the solid material wastes. And the non-metal materials are separated before the stream of waste reaches the magnetic rotor. By adjusting the location of the magnetic rotor related to conveyor belt in accordion with the sizes of the waste particles, bigger sized particles can be separated efficiently. The design and simulation is done by a Finite Element Analysis software named Comsol Multiphysics. The software allowed usto simulate magnetic properties of the eddy current separator made of three dimensional permanent magnets. Inthecourseof work,themagneticfluxvariationaroundthesurroundingsofthemachine can be analyzed. the ejection force on various particles are founded from the computed data in Comsol. The particles’ induced current density and the conductivity influence can be originated. From this study, a way is founded to analyze and compare among different designs of the machine. Thus the process of making a prototype becomes much easier and the machine be much more effective. By analytical methods and finite element analysis the efficiency of the design of the machine can be tested. The paper shows a technical overview for the improvement of eddy current separation equipment so that the less conducting metals could also be recovered utterly. This study could be of great value to the recycling industries and waste sorting plants. No practical implications proved to be a limitation for this research. And for the finite element method, several practical aspects were neglected that could affect the results of the simulation. Eddy current separator, the most important machine among the machines of a solid waste management plant, can be designed and manufacturedwith greater efficiency from the analysis of this study. And the result of the study can be used for optimizing the design of the typical eddy current separators used by the waste sorting industries.