Research: Tropical Plant May Cut Nutrient Removal Costs
By Sara Jerome
New research shows a tropical plant known as Job's Tears may be useful in treating wastewater.
Scientists are testing whether this plant, a tall grain native to Asia, can help remove nitrogen and other nutrients from wastewater, according to Phys.org.
They say it may be particularly useful in countries such as Vietnam and Thailand where wastewater is not always cleaned before it is pumped back into waterways. These practices endanger public health.
For instance, in Thailand, failure to treat wastewater is consistently rated as a major health problem. But building a sufficient number of new wastewater treatment plants could cost billions of dollars, according to the Thailand Environmental Monitor published by The World Bank.
But scientists say Job's Tears shows promise for cutting the economic barriers to wastewater treatment in developing countries.
"Treating wastewater by using a native plant species is particularly relevant for developing countries such as Thailand as it is low tech, low energy, cost-effective and has potential on a large scale," Dennis Konnerup, an author of the new study, said in Phys.org.
This notion is still in the testing phase. In the recent experiment, "seedlings were planted in different nitrogen based solutions consisting of either ammonium (NH4+) or nitrate (NO3-) and at four levels of pH: 3.5, 5.0, 6.5 and 8.5."
After 40 days, scientists checked how much the plants had grown under each condition. Plants appeared to grow more in solutions with higher nutrient content, suggesting the plants were absorbing those nutrients, according to the report.
Nutrient removal is a major focus in the water sector. For coverage of all aspects of this issue, from economic to scientific, check out Water Online's nutrient removal page.
Attempts to treat nutrients in drinking and wastewater can create a vicious cycle.
Nutrients can "increase the need to chlorinate drinking water, which, in turn, leads to higher levels of disinfection by-products that have been shown to increase the risk of cancer," according to an EPA report.
Image credit: "Job's Tears," © 2009 InAweofGod'sCreation, used under a Creative Commons Attribution license: http://creativecommons.org/licenses/by/2.0/deed.en