Combined Chlorine-based and UV Radiation method holds promise in treatment of wastewater for potable reuse

Purdue University researchers have developed an innovative method to detoxify water – using chlorine and UV radiation – offering new hope for water-stressed areas and helping enable greater reuse of wastewater (Phys.org, August 9).

“Our discovery in helping to provide more people with access to clean water is taking common elements of water treatment like UV radiation and chlorine and using them in a new way,” Ernest R. Blatchley III, an engineering professor at Purdue University, told Phys.org.

The new method holds particular promise in water-stressed regions such as the U.S. Southwest, where the reuse of treated wastewater for irrigation and drinking water (“water reuse”) is already occurring or being considered to supplement local water supplies. More unpredictable weather coupled with a growing human population and demand for food is increasing the reliance on water supplies that are classified as being of marginal or poor quality, such as wastewater. In turn, this increases the need for more effective water treatment methods to remove contaminants.

The Purdue team developed a method to selectively break down amines, which are derived from ammonia and can be toxic to humans. “Reuse applications generally involve water sources that are compromised and likely to contain relatively high concentrations of amines,” writes Phys.org. The method involves adding chlorine followed by UV radiation. “Conventional water treatment methods are generally ineffective for removal, degradation or detoxification of these compounds. Our method allows current treatments to be modified to provide cleaner and safer water,” Blatchley stated.

The American Chemistry Council supported Dr. Blatchley’s past studies of the effects of combined UV radiation and chlorination treatment of swimming pool water on water and air chemistry.