Changes in NOM fractionation through treatment: A comparison of ozonation and chlorination.

NOM isolation and fractionation to provide insight into the effectiveness of ozonation vs, conventional water treatment was done. In this research, the dissolved portion of natural organic matter (NOM) or dissolved organic matter (DOM) at two surface drinking water treatment plants that treat the same source water was fractionated by resin adsorption. The first treatment plant uses conventional treatment (coagulation, sedimentation, and filtration) with intermediate free chlorination and post chlorination while the second plant uses conventional treatment with pre and intermediate ozonation, and multi-media filtration unit operation. Several different sampling locations within each plant were selected for DOM isolation and fractionation into six fractions (hydrophobic acid, neutral and base, and hydrophilic acid, neutral, and base). The effectiveness of each treatment plant on the oxidation and removal of each organic fraction are discussed. Oxidation by ozone leads to better overall performance in the removal of DOM.