How to recycle LED lamps economically

LED light sources currently have a variety of forms. In order to effectively recover them, they must first be broken into components. When recycling LED diodes, they are kept as intact as possible so that collection is critical.

Light-emitting diodes (LEDs) are used in many products such as televisions, lamps, and light sources. In addition, they have also penetrated the automotive lighting market to a greater extent. However, today there is no suitable process for recycling these items. However, researchers have now developed a way to mechanically separate LEDs.

Modern light sources are made from a variety of materials, with glass or plastic housings, ceramic or aluminum heat sinks, and resistors and cables with copper. The most valuable materials are inside the LEDs themselves. They are indium and germanium in semiconductor diodes and rare earth elements such as germanium or germanium in phosphors, which make diodes relatively expensive and marginally profitable. “Recycling companies are now starting to collect LED products, but because there is currently no suitable recycling process, they are often just stored up. The main goal is to recover valuable materials. It is only a matter of time before recycling companies begin to deal with LEDs,” Flau said. Jrg Zimmermann of the Enhoff Material Recovery and Resource Strategy Project Team said.

Use Shockwave to help separate components

The researchers used the "electrohydraulic crushing" process to break LED lamps into parts without damaging the LED itself. It used shock waves generated by electric pulses in a water bath to separate the components at predetermined breaking points, and then the components could be separated. Recycling. The researchers adjusted their experimental setup to recycle LED retrofit fluorescent tubes. These tubes resemble traditional fluorescent tubes and use standard fluorescent tube sockets. "This method is also applicable in principle for LEDs of other sizes, such as LEDs for televisions or headlights, and LEDs in other appliances," explains Zimmermann.

The precondition for an effective recycling process is the clean separation of the components. “In order to effectively separate and recycle all the components of the LED luminaire, a completely different approach is required to produce large amounts of semiconductors and fluorescent materials,” Zimmermann said. If the entire lamp tube is crushed, it will be more difficult to separate the resulting material mixture. The decomposition of LED luminaires to the component level also makes it easier to recover more of the contained material, which is achieved by collecting a large number of similar components that are rich in these elements. Zimmermann clarified that this process only involves a large amount of money, which is profitable for recyclers and manufacturers.

"We are also testing whether the comminution process can be repeated until the desired material is separated," Zimmerman said. Researchers can adjust parameters of the experimental device, such as the type and quantity of the liquid, the size of the vessel, or the pulse voltage, making the separation possible. Precisely occurs at a specific breaking point. "Specifically speaking, it is the number of pulses that determine how the components will be separated." The electrohydraulic comminution process is currently under scrutiny and further improvement, and has been extended to other LED applications. "Our research has shown that mechanical separation is to increase the LED A practical way to recover the economics of lamps,” Zimmermann said.