The recycling of beverage containers made from polyethylene terephthalate (PET) is garnering higher purity and yield with high speed, high strength eddy current separation technology from Eriez®.
Eriez' newest line of Eddy Current Separators deliver exceptional nonferrous particle separation from PET flake. Recyclers can obtain a single pass aluminum reduction up to 92 percent and achieve a clean PET yield of 97 percent to 99 percent. According to studies conducted by Eriez, a one percent improvement in good product yield can save a company up to $230,000 in recycled PET annually with a 60-inch wide Eddy Current Separator.
Once the PET is purified, it can be re-used to make fiber, banding, or blended to make recycled content beverage and food containers. Recycled PET can be used in such diverse products as carpet, food containers, clothing, auto parts, tool handles and sleeping bag insulation.
Eriez' Eddy Current Separators use powerful Rare Earth magnets that are arranged into a high-speed, composite shelled rotor. The PET containing metal contaminants—such as aluminum—is fed onto a conveyor belt in a controlled, low-density thin layer. The belt then passes over the rotating magnets and eddy currents are created in the aluminum.
When the polarity of the magnetic field around the aluminum is the same as the rotating magnets, the aluminum is repelled from the magnet. This causes the trajectory of the nonferrous metal to be different than the PET flake. The two streams of material are separated by an adjustable splitter in a simple, high-volume manner.
The heart of the separator is the Rare Earth Arched (REA) rotor, which uses powerful Rare Earth magnets that are curved to the shell contour. This high-frequency rotor has 22 poles and offers effective removal of small and medium nonferrous metals from aluminum cans as well as electronic scrap, plastics, glass cullet, foundry sand and urban wood waste. This REA rotor uses patented Kevlar/ceramic tile surface shells and grease retainer chambers and is balanced to operate up to 3200 RPM. Normal bearing life with good maintenance is calculated to be more than 15 years.
The equipment controls are housed in a NEMA 4-rated enclosure and include a belt speed tachometer. Also available is an Eriez vibratory pan feeder, hopper and belt conveyor to assure an even, controlled flake depth to enhance the separation performance.