Special applications
Magnetic separation: economics and special applications

The main aim of dry purification by low-intensity magnetic separation is to eliminate wear iron introduced into products during processing (crushing, grinding, etc.) or transportation.

Most of the magnetic drums described in the article can be used for purification purposes; however, sandwich-pole magnetic arrangements are preferred for higher purification efficiency (higher magnetic forces than those developed by conventional systems), or salient-pole circuits in which ceramic magnets have been replaced by magnets based on rare-earth element alloys (e.g. NdFeB) to increase the magnetic force developed.

Depending on the product to be treated and the type of equipment used, allowable treatment flows vary from a few hundred kilograms per hour to several tens of tons per hour.

Rare-earth permanent...