Development of a model for predicting trihalomethanes propagation in water distribution systems.

The rate of Trihalomethanes (THM) formation was experimentally observed to be first-order with respect to chlorine, and first-order with respect to humic acid precursors, and the overall reaction order was second-order. THM formation rate expression was formulated as a function of the concentration of THM Formation Potential (THMFP), residual chlorine concentration, reaction time and reaction temperature. A model is developed to estimate THM in water distribution systems. Since the calculated results are close to the measured values in the distribution system, it is suggested that this model is applicable to actual water distribution systems.