Eriez has played a pioneering role in the field of eddy current separation since 1969 when it patented both permanent magnetic and electromagnetic systems. Over time, the company has refined its designs to incorporate improved permanent magnetic circuits using rare earth materials, resulting in stronger eddy currents that offer effective separation of non-ferrous metals. These developments have built upon the original concept while ensuring that the machines meet the growing demands of modern recycling and recovery operations.
The operating principle of these eddy current separators is straightforward yet powerful. Permanent rare earth magnets induce eddy currents into metallic particles and these currents create repelling forces that drive the particles away from the flow of non-metallic materials. The outcome is a cleaner output that can move forward for further processing with minimal loss of product. This selectivity is one of the defining advantages of the technology as it ensures the recovery of valuable metals without compromising the integrity of other materials in the stream.
To advance separation performance further, Eriez developed the RevX-E eddy current separator. This model features an eccentrically mounted magnetic rotor inside a non-conductive shell, which focuses the magnetic field at the end of the belt. The design brings several practical benefits. It allows conveyor belt changes in as little as 10 minutes due to a cantilevered frame, while rack-and-pinion splitter adjustments provide accurate placement for optimal separation. Maintenance is simplified with large access panels around the machine, while the compact footprint reduces the space needed in processing facilities. Both the rotor and conveyor are driven directly, contributing to operational efficiency.
Read more: Eriez – seeing ASR differently
The RevX-E is available in widths of one, 1.2 and 1.5 metres, with rotor assemblies designed for different size fractions. The LT2 rotor is an eight-pole rare earth eccentric rotor suitable for coarse fractions greater than one inch. The ST22 rotor is a 22-pole rare earth design intended for material sized between 0.63cm and 2.54cm. These options allow operators to match machine configuration to the size distribution of their feed material.
Eriez has also introduced an Ultra High-Frequency eddy current separator to recover ultra-fine non-ferrous particles that conventional units often miss. This separator combines a specially designed rotor that produces high gauss at the belt surface with a large number of magnetic poles operating at elevated speeds. The result is ultra high-frequency field changes capable of separating small fractions including bare copper wire. It offers an economical means to enhance zorba recovery without the expense of sensor-based or optical sorting equipment.
Each ultra high-frequency unit, typically one metre wide, is shipped with an Eriez Brute Force feeder to ensure even material distribution across the conveyor. These systems can recover valuable non-ferrous metals as small as 2-3mm. Features include a carbon fibre shell, precise splitter adjustments, a rotor operating at higher RPMs and the ability to deliver consistent high-quality separation across the
width of the belt.
Together these technologies demonstrate Eriez’s ongoing commitment to advancing non-ferrous metal recovery. From the original separators patented in 1969 to today’s RevX-E and Ultra High-Frequency models, the company has continually refined its systems to deliver efficiency, selectivity and reliability in recycling and processing operations.