A light-emitting diode (LED) is comprised of a two-lead semiconductor light source. This means that LED bulbs work on the movement of electrons in the semiconductor, allowing them to be easily used in any electrical circuit. This feature — along with their long lifespan — has resulted in LEDs replacing incandescent light bulbs in many electronics, and has aided in the evolution of smaller and slimmer electronics.
While LEDs provide many benefits, there has been growing concern surrounding what happens when they die. This is not only true for LEDs, but for many electronics in general, especially as the rate of newer models and gadgets going to market is so high. This has left many recycling companies wondering what to do with the e-waste we produce.
Can we recycle LEDs?
That’s the question posed to Dr. Maria Holuszko and her PhD student Amit Kumar at the Urban Mining Innovation Centre (UMIC) at UBC. “Processing LEDs was something [a] recycling company didn’t know how to do,” said Holuszko, but it was a project perfectly suited for UMIC.
One of the main goals for the team at the UMIC is to close the loop in the economic circle through the recovery of valuable materials from waste streams, leading to the ultimate goal of zero waste.
Holuszko said that since “the recycling industry is where everything ends up before going into landfills,” her and Kumar utilized their expertise in mining engineering to help Contact Environmental, a recycling company, develop a solution to recycle LEDs. Contact Environmental is BC’s major lamp recycler, “responsible for processing up to 90 per cent of bulbs and lighting elements” in the province, said Holuszko.
Making sure that any solution developed did not involve the use of harsh chemical treatments or high temperatures, Kumar utilized equipment already found at Contact Environmental. Kumar said that by using processes that have “been used for the last 20 years in the mining industry” as well as in the recycling of electronics, he tried them out on LEDs to see if they worked. Since he was working with Contact Environmental, specific details on what the process is could not be given. However, Kumar was able to give a general overview of the process. Through a combination of steps that target the “density, magnetic and gravity,” said Kumar, he was able to develop a simple, economical process based on the physical attributes of the LEDs.
The process is able to recover higher amounts of valuable metals than initial estimates. With the success of this process, and significant amounts of metals such as copper, lead, zinc and silver being kept out of landfills, Holuszko and the team at the UMIC plan to build on this success. In the short term, they plan on improving their process even further to improve the recovery of metals. As for the long term, they hope that through public awareness, the UMIC will grow and attract the attention of other companies in the urban waste stream.
The development of smaller, lighter and faster electronics that incorporate composite materials pose many challenges for the recycling industry. However, through the development of adaptable processes that can be modified for specific e-waste streams, Holuszk and Kumar believe that the challenges posed by e-waste can be solved.
Correction: A previous version of this article incorrectly smelled Amit Kumar's name. The Ubyssey regrets this error.