Degradation of ferrosilicon media in dense medium separation circuits

Observations on the degradation of various types of atomized and milled ferrosilicon in laboratory trials and operating DMS plants are presented. Mechanisms contributing to the loss of media through mechanical disintegration and electrochemical corrosion are identified. It is evident that significant differences exist between the different types of ferrosilicon powder available from commercial sources. Although the performance of a given powder in a specific DMS circuit cannot be predicted easily, certain precautions can be employed to minimise ferrosilicon losses.