Crumb rubber, chewed up old tires, is used on athletic tracks, playgrounds, and increasingly as an alternative to mulch. Now, Dr. Yuefeng Xie, associate professor of environmental engineering at Penn State Harrisburg, has found crumb rubber makes an excellent water filter.
"My research has found that crumb rubber, derived from waste tires, can be used as a filter media," Xie explains. "The crumb rubber could be used for treating wastewater, ship ballast water, and storm water."
His research shows that the crumb rubber is more efficient than anthracite or sand filters. More traditional filters rearrange themselves to allow larger particles through at the bottom, and finer particles filtered out on top- this is exactly the opposite of what you want to have happen. The rubber keeps the large particles out on top, and thus creates a much higher throughput. The rubber filter is also lighter in weight, making it ideal for portable emergency filtration. The use of waste tires also makes this an much cheaper option, and better than sitting in a landfill.:: Penn State