Using audio CDs, researchers from National Taiwan University have created a new wastewater treatment device, which can be used to clean sewage water.
With the advent of MP3s, iPods and online music streaming, audio CDs have become obsolete to a large extend. People are now left with their large collections of CDs and don't really know what to do with them. Some have begun using them to create abstract art while other just let them gather dust in their cupboards.
Now, researchers from National Taiwan University have come up with an innovative and environment-friendly usage for these CDs. People can now use them to clean sewage water. The team of researchers created a new wastewater treatment device that they will present at the Optical Society's (OSA) Annual Meeting, Frontiers in Optics (FiO) 2013, being held Oct. 6-10 in Orlando, Fla.
To construct the device, researchers used the large surface area of CDs to grow tiny, upright zinc oxide nanorods about a thousandth the width of a human hair. Zinc oxide can be used to break down organic molecules with the help of UV light. Since it is inexpensive to produce, it can be used to break down pollutants in sewage. This is the first time researchers have experimented on growing zinc oxide on optical discs.
Since these discs are light and spin at a great speed, when water is dropped over its surface, the water spreads out in a thin film that light can easily pass through, speeding up the degradation process.
The newly created device is one cubic foot in volume and includes a UV light source and a system that re-circulates water so that pollutants are further broken down.
To test the efficiency of the device, researchers used a solution of methyl orange dye. This solution was treated in the device for approximately 60 minutes. Researchers noted that after the treatment, approximately 95 percent of the pollutants were broken down. Researchers claimed that the device is capable of cleaning 150 ml of water in one minute. Researchers hope to make the device more effective and work much faster in future.
