virvelstrømseparator

A virvelstrømseparator, also known as an eddy current separator, is a non-contact sorting device used to separate non-ferrous metals from other materials. It operates based on the principle of electromagnetic induction. When a stream of mixed materials passes through a rapidly rotating magnetic field, eddy currents are induced within any conductive materials, such as aluminum or copper. These induced eddy currents generate their own magnetic fields, which oppose the primary magnetic field. This opposition creates a repulsive force that pushes the conductive materials away from the non-conductive materials.

The core of a virvelstrømseparator is a high-speed rotor containing powerful permanent magnets or electromagnets. This rotor is housed within a non-magnetic splitter, which is crucial for separating the trajectories of the conductive and non-conductive fractions. As the material stream falls over the end of a conveyor belt and into the magnetic field, the eddy currents are generated in the non-ferrous metals. The strength of the induced eddy currents, and thus the resulting repulsive force, is dependent on the material's conductivity and size, as well as the strength and speed of the magnetic field.

Virvelstrømseparatorer are widely employed in various recycling and waste processing applications, including the separation of aluminum cans from municipal solid waste, the recovery of non-ferrous metals from shredder residue, and in the processing of electronic waste. They are effective in separating materials like aluminum, copper, brass, and lead, while allowing non-metallic materials such as plastic, glass, and wood to follow a different trajectory, thus achieving separation. The technology offers a cost-effective and efficient method for recovering valuable non-ferrous metals.