The scientific journal Ozone Science and Engineering published an article entitled: Efficacy of Ozone to Reduce Chlorinated Disinfection By-Products in Quebec (Canada) Drinking Water Facilities, authored by Ladji Meite; Macellin Fotsing and Benoit Barbeau. The following post is a summary of that article.
The impact of ozonation on the reduction of chlorinated disinfection by-products (DBPs) formation was investigated in 15 full-scale Quebec’s WTPs using ozonation as part of their treatment.
The most common locations for the ozonation process were respectively post-ozonation (9), intermediate ozonation (3), and pre-ozonation (3).
Sampling campaigns were replicated for each WTP in warm waters (June–August) as well as cold waters (November–April). Samples were collected before and after full-scale ozonation and were chlorinated in the laboratory to perform DBPs measurements under uniform formation conditions (UFC) tests. A lab-scale ozonation was also performed on each sample to standardize ozonation conditions of all investigated waters. As part of the research, total trihalomethanes (TTHM) and the sum of six haloacetic acids (HAA6) were measured after chlorination
In full-scale ozonation conditions, TTHM-UFC and HAA6-UFC reductions averaged respectively 27 and 32%.