Plant roots enmeshed in layers of discarded materials inside upright pipes can purify dirty water from a washing machine, making it fit for growing vegetables and flushing toilets, according to Penn State horticulturists.
"Our global fresh water supplies are fast depleting," said Robert D. Cameron, doctoral student in horticulture. "So it is critical that we begin to look at alternatives on how we can take wastewater and turn it into a resource."
Cameron and Robert D. Berghage, associate professor of horticulture, use discarded materials and a combination of plant and bacterial communities to treat water from a washing machine and other wastewater.
According to Cameron, this design is superior to previous living treatment systems in that it requires much less space and is much more efficient at removing contaminants.
"We have shown that with this system we can take wastewater from a washing machine and remove more than 90 percent of the pollutants within three days," said Cameron. "The treated water had very low levels of suspended solids and no detectable levels of e.coli."
Cameron presented the work today (May 5) at a meeting on organic and sustainable agriculture in Havana.
The water treatment system consists of two seven-foot long plastic corrugated pipes a foot in diameter. The researchers placed these pipes upright three feet apart in a basin containing a foot of potting soil and crushed limestone.
"We planted the three feet by five feet basin at the foot of the pipes with papyrus and horsetail reed," said Cameron. "Just like in a wetland, the roots of these plants and associated bacteria clean the water as it flows under the basin surface and through the two columns."
Both culvert pipes are filled with alternating layers of porous rocks, composted cow manure, peat moss, tire crumbs, potting soil and crushed limestone.
Researchers planted vegetables and ornamental plants -- tomatoes, peppers, rosema
|Contact: Amitabh Avasthi|