The control of disinfection by-products precursors by advanced methods of water treatment

In the article, the results of the research on reactivity of natural organic matter in regard to disinfection by-products, specifically trihalomethanes (THM) formation, with the use of model waters, are discussed. Additionally, the evaluation of different processes used in water treatment, i.e. photocatalysis, MIEX (R) DOC and membrane processes, is made. It was found that the affinity of particular natural organic matter compounds to form chlorination by-products could be arranged in a series: hydrophobic fraction (HA) > hydrophilic fraction (FA). The applied treatment processes efficiently decreased the concentration of disinfection by-products (DBPs) precursors and characterized with different removal mechanisms. Water treated by means of photocatalysis (specific potential of Sigma THM was 30 mu g/mg dissolved organic carbon (DOC) for HA and 12 mu g/mg DOC for FA) revealed lower affinity to form chlorination by-products in comparison with water undergone to MIEX (R) DOC process (specific potential of Sigma THM was 38 mu g/mg DOC for HA and 29 mu g/mg DOC for FA). Moreover, combination of those methods with membrane processes efficiently reduced DBPs formation potential. In nanofiltration effluents DBPs potential were very low and equalled to 50 mu g/L for HA and 15 mu g/L for FA.