Researchers at Purdue University realized we were facing a major e-waste problem -- 3 million tons of e-waste were generated in the U.S. in 2007 alone -- one that was about to get worse as people began retiring LCD flat-screen TVs and monitors made before 2009. Those models are backlighted with cold cathode fluorescent lamps or CCFLs, which contain mercury, making them hazardous to dispose of or incinerate.
"Over the next few years, it is expected that hundreds of millions of CCFL-backlighted LCDs will retire each year," said Fu Zhao, an assistant professor in the School of Mechanical Engineering and Division of Environmental and Ecological Engineering. "Without proper treatment, these used LCDs could lead to serious damage to the environment."
While LCD hardware typically has a lifespan of 10 to 20 years, most people don't hang on to it that long. Technology advances and the constant release of new models of electronics means people are upgrading more frequently than that.
To tackle that problem, the researchers are working to develop a new way to recycle these displays that doesn't involve incineration or shipping them overseas. Electronics contain toxic materials like heavy metals and brominated flame retardants that can leach into ground water or turn into "super toxicants" like dioxin when incinerated, so safe disposal is incredibly important. Electronic devices also contain valuable materials that can be recovered and reused.
The project is focusing on creating specially-designed tools that can disassemble LCDs in a way that lets them recover high-value components, reduce environmental hazards and keep costs low. Specifically, tools that can more easily remove a monitor's housing and detach circuit boards and metal frames, then separate polarizing filters, glass, liquid crystals, and the mercury-containing backlight unit, which will allow for quick separation and recovery of valuable and toxic materials.
Materials like gold and indium can be recovered to be used in more electronics, while the mercury can be removed and disposed of properly.
Since 2010, LED backlights have replaced CCFLs in most LCD flat-screens, but even though LEDs screens contain no toxic materials, they will still be e-waste at the end of their lives and these recycling tools will help to dispose of them properly as well.