“Ozone” and “GAC filtration” synergy for removal of emerging micropollutants in a drinking water treatment plant?

Ozonation plays an essential role in water disinfection to inactivate viruses, bacteria and some parasites (Giardia). Ozone treatment rates to attain disinfection goals also result in oxidation reactions of emerging pollutants. Pharmaceuticals–except Ciprofloxacin–are very reactive to ozone: they are removed as early as the transfer compartment outlet even at an ozone treatment rate of less than 1 g/m3. Glyphosate, AMPA, Amitrole and Diuron–the four major pesticides in the Seine, Marne and Oise rivers–are reactive to ozone. Twenty-one pesticides are only partially reactive to ozone and an additional “GAC filtration” is needed to remove them. Further investigations have been planned to study the removal of Phthalates, Nonylphenols and Hormones by combining the “Ozone” and “GAC filtration” process units.

Keywords: GAC, micropollutants, ozone, pesticides, pharmaceuticals