Formation of POX and NPOX with chlorination of fulvic acid in water: Empirical models

Chlorinated disinfection byproducts (DBPs) are formed by chlorination of drinking water. In this study, laboratory chlorination experiments were conducted with respect to the influence of reaction time, TOC, chlorine dose, pH and temperature on formation of POX (purgeable organic halide) and NPOX (non-purgeable organic halide). Non-linear regression models were generated as follows: [POX]=7.2t0.08[TOC]0.49[Cl]0.41pH+8.6) e(−468.5/7) [NPOX]=28.7t0.02[TOC]0.53[Cl]0.44(20.9−pH) e(−632.4/7) where t is the reaction time (h), [TOC] is the concentration of total organic carbon (mg/l), [Cl2] is the concentration of applied chlorine dose (mg/l) and T is the absolute temperature (K). Further, the above models were tested with three water samples. We have also investigated the influence of coexistent ammonia-nitrogen.