Pretreatment Comparison Between Preoxidation and Prechlorination on the Changing of Natural Organic Matter

摘要

Surface water is mainly used as source water after treatment process to produce drinking water or clean water. The existence of natural organic matter (NOM) in surface water caused some problems in water treatment, instead of taste and aesthetic issues. Preoxidation and prechlorination are oxidation processes that have been used widely for different purposes in water treatment process. The objective of the study was to compare performance of permanganate preoxidation and prechlorination in removing NOM and to know the changing of NOM in term of its functional group properties by using Fourier-Transform Infrared (FTIR). TOC concentration and UV210 value were used to represent NOM parameter. The results showed that prechlorination has a higher performance to treat NOM in water than permanganate preoxidation. Further, prechlorination could be considered as pretreatment of coagulation in order to improve its performance in removing TOC concentration and aromatic compounds. FTIR could be applied to track the changing of NOM functional groups, and organic properties in prechlorination followed by alum coagulation have the lowest percentage transmittance.