NOM characterization and treatability

Samples were prepared from water sources representative of the major sources of organic matter in North America (deciduous forest, coniferous forest, desert vegetation, and marshes and swamps.). Treatability studies were evaluated on a batch basis for coagulation, lime softening and ozonation. Continuous flow studies evaluated conventional treatment followed by granular activated carbon (GAC) adsorption with and without preozonation. Each source and treated water sample was analysed for the characterization of natural organic matter (NOM). Coagulation removed NOM intact with preferential removal of humic NOM and higher molecular weight NOM. Ozone converted humic to nonhumic NOM, higher molecular weight to lower molecular weight NOM, and destroyed ultraviolet-absorbance properties. GAC initially removed humic and higher molecular weight NOM, but there was some reduction of nonhumic and lower molecular weight DOC. The processes could affect the ability of succeeding processes to remove NOM. The fate of bromide through separation and treatment processes was important in understanding trihalomethane (and other disinfection byproducts) formation. There are 30 references.