Mathematical model and experimental investigation for eddy current separation of nonferrous metals

Abstract

Comprehensive recovery for nonferrous metals from solid wastes has a significant importance for China‘s sustainable development; otherwise, it will lead to the vast loss for such values and subsequently the serious heavy metal pollution. In this investigation, a pilot-scale eddy current separator (ECS) is designed to recycle nonferrous metals from solid wastes. Firstly, a general mathematical model of eddy current force for the ECS process is established, and the important operating factors of the process are analyzed. After that, the effects of the four key operating factors, i.e., metal size, metal conductivity/density ratio, magnetic induction and feed velocity, on the ECS performance are investigated in detail using the pilot-scale ECS in separating copper and aluminum metals. Also, a mixture of Cu-Al metals is tested for separation from each other and its separation performance is evaluated. The results of separations have generally proved the mathematical model, and the ECS effectively separates the nonferrous metals, with high recovery for the metals. It is thus concluded that the ECS has provided an effective way in recycling nonferrous metals from solid wastes.