Once the magnetic separator has removed the iron, the metals worth the most are still in the flow: aluminium and copper. They are not magnetic, so they cannot be attracted. An eddy current separator is the only machine that can extract them automatically, and it does so through an elegant piece of physics.
A magnetic rotor spins at very high speed. When a conductive metal passes through this varying field, eddy currents are induced inside it. Those induced currents in turn generate their own magnetic field, which opposes the rotor's field. The metal is effectively repelled, thrown forward over a splitter plate, while plastic, glass and the other non-conductive materials free-fall over the rotor. See the full range of waste sorting equipment and where each machine sits in the flow.
Key Advantages of an Eddy Current Separator
• It recovers the most valuable fraction, aluminium and copper carry the best price in a municipal waste flow, and an eddy current separator is the only way to extract them automatically at industrial throughput.
• Purity is set from the plate, the splitter plate position decides the balance between how much metal you recover and how clean it is, so you set the priority according to your buyer's requirements.
• No mechanical contact, separation is done by magnetic field rather than knives or screens, so there are no parts that cut or dull against abrasive waste.
• Low consumption against the value recovered, a typical rotor is driven by a motor of a few kilowatts, while the fraction recovered is the most valuable in the whole line.
• Concentric or eccentric rotor, the eccentric version concentrates the field in the discharge zone and tolerates iron left accidentally in the flow far better.
• It integrates into the existing line, it mounts at the end of a conveyor as a discharge station, with no reconfiguration of the flow.
Technical Specifications, Eddy Current Separator
| Parameter | Configuration |
|---|---|
| Working principle | High-speed magnetic rotor, induced eddy currents |
| Metals recovered | Aluminium, copper, zinc, other conductive metals |
| Rotor type | Concentric or eccentric, on request |
| Rotor speed adjustment | Yes, to suit particle size and metal type |
| Splitter plate | Adjustable position |
| Working width | Set to match the belt width in the line |
| Mandatory upstream requirement | Magnetic separator for ferrous metals |
| Recommended particle size | Screened flow with uniform particle size |
We do not publish a throughput table because the performance of an eddy current separator depends almost entirely on the particle size of the flow and the target metal, far more than on the size of the machine. The configuration and final power are set after an analysis of your material.
Applications for Non-Ferrous Metal Recovery
• Municipal waste sorting plants, recovering aluminium cans and copper parts from the mixed flow.
• Electronic waste, extracting aluminium and copper from shredded material, where the concentration is high.
• Vehicle recycling, separating non-ferrous metals from automotive shredder residue, one of the most valuable applications.
• Glass recycling, removing caps and non-ferrous metal parts from cullet.
• Construction waste, recovering aluminium profiles and copper pipework from demolition material.
• Plastic recycling, cleaning metal particles out of flakes, a quality requirement for pelletising.
How It Works
Material is carried by a conveyor to its end, where the magnetic rotor sits. The rotor turns independently of the belt, at a much higher speed, and generates a very rapidly changing magnetic field. When an object of conductive metal, an aluminium can or a piece of copper, passes through this varying field, the laws of electromagnetic induction cause eddy currents to appear inside it. Those currents in turn generate their own magnetic field, oriented so as to oppose the rotor's field. The two fields repel, and the metal object is propelled forward along a longer trajectory than a normal fall. A splitter plate, positioned exactly where the trajectories diverge, divides the flow in two: the repelled metals pass over the plate, while non-conductive materials, plastic, glass, paper, free-fall behind it. The plate position is adjustable, and that adjustment is what decides the trade-off between recovery and purity: closer, and you recover more metal but with contaminants; further away, and the metal is very clean but you lose part of it.
Selection Guide
Before any discussion about models, two conditions must be met. First: the flow must already have passed through a magnetic separator. Iron left in the material is violently attracted to the rotor, sticks to it, heats up and destroys the magnets. This is not a recommendation, it is a requirement. Second: the material must be screened, with relatively uniform particle size. An eddy current separator works most accurately on a narrow size band, because the repulsion force depends on the ratio between an object's mass and its surface. Once those conditions are met, the choice comes down to belt width and rotor type. An eccentric rotor concentrates the field in the discharge zone, which reduces heating and tolerates accidental iron better, so it is the safer choice for municipal flows.
Frequently Asked Questions
Why is a magnetic separator mandatory beforehand?
Because iron is strongly attracted to the magnetic rotor, sticks to it and does not come off. Friction heats it, and the heat degrades the permanent magnets in the rotor, which are the most expensive part of the machine. A magnetic separator upstream is a measure to protect the investment, not an option.
Which metals does it actually recover?
All conductive non-ferrous metals: aluminium first of all, then copper, zinc, lead and their alloys. The better the electrical conductivity and the lower the density, the more strongly the object is repelled. That is why aluminium separates most easily, and lead, which is dense and less conductive, the hardest.
How do I choose between maximum recovery and maximum purity?
From the splitter plate position. Close to the rotor, it catches more metal but also more contaminants that land past the plate. Further away, the metal fraction is very clean, but part of the less strongly repelled metal is lost into the waste stream. The setting follows what your metal buyer requires.
What is the difference between a concentric and an eccentric rotor?
On a concentric rotor the magnets are distributed evenly around the full circumference. On an eccentric one the field is concentrated in the discharge zone, where it does useful work. The eccentric version runs cooler, tolerates iron left accidentally in the flow better and is generally recommended for municipal waste.
Is the equipment supplied new?
Yes. We supply new units only, made to order for your application, with complete technical documentation.
What maintenance does an eddy current separator need?
Checking the conveyor belt and the rotor bearings, since the rotor spins at high speed and is the most heavily loaded part, monitoring rotor temperature, adjusting the splitter plate and verifying that the upstream magnetic separator is working correctly. That last point matters most for the machine's service life.
Why URSTAG?
URSTAG is a premium brand of recycling equipment, with over 15 years of experience. You don't just get a machine, you get a solution engineered by specialists, built from top-tier components and backed by a team that supports you from design through commissioning.
• European engineering, every machine and every complete line is designed by our engineering teams in Europe, with a focus on reliability, safety and energy efficiency.
• Premium components, we build on motors and automation from industry leaders: Siemens, Schneider Electric, ABB, WEG, SEW-Eurodrive, NORD Drivesystems and Bonfiglioli.
• Over 15 years of experience, we know how materials and machines behave in real-world operation, and we configure each solution for your flow and volume.
• New equipment, configured for you, we supply new units, made to order for your application, with complete technical documentation.
• Delivery, installation and training included, we handle transport, commissioning and operator training, with support throughout the equipment's life.
As a premium brand, URSTAG relies on European engineering, top-tier components and experience. You choose a partner that supports your production long term, with equipment built to run reliably in demanding industrial environments.
