Predicting the formation of trihalomethanes and haloacetic acids in water treated with chlorine dioxide

Factors affecting formation of disinfection byproducts (DBPs) such as trihalomethane THM and haloacetic acid HAA in drinking water treated with chlorine dioxide ClO₂ as disinfectant were investigated. The collected data were used to develop mathematical models that predict the formation of THM and HAA in terms of each of the studied factor: ClO₂ dose, total organic content TOC, bromide ion concentration, pH, temperature and contact time. Mathematical models were developed for four trihalomethane species, as well as total trihalomethanes TTHM, in addition to six haloacetic acid species and total haloacetic acids THAA. Predicted THM and HAA concentrations using developed models were compared to actual concentrations measured in real samples. Results showed good correlation between measured and calculated values. This means that the method presented could be used to obtain good estimates of THM and HAA concentrations formed when the water is treated with ClO₂ under different experimental conditions.