AWWA WQTC62470

Different studies have demonstrated that natural organic matter (NOM), composed of humic as well as non-humic substances, in natural water is a key membrane foulant. Nevertheless the complexity of NOM has not allowed identification of the fraction or part of NOM that exactly causes membrane fouling. Several indicators are available to determine the NOM fouling potential of a membrane feedwater. These include, among others, ultraviolet (UV) absorbance at 254 nm (UVA₂₅₄), color, total organic carbon (TOC), humic content, specific UVA₂₅₄, liquid chromatography ¿¿¿¿¿¿¿¿ organic carbon detection (LC-OCD), size exclusion chromatography ¿¿¿¿¿¿¿¿ UVA ratio index (SEC-URI), SEC-fluorescence, colloid size, assimilable organic carbon (AOC), biofilm formation rate (BFR) and specific oxygen consumption rate (SOCR). However, NOM fouling rates do not appear to correlate with traditional water quality parameters such as color, UV absorbance or DOC concentration, and pilot plant trials are still needed to determine the level of fouling that would occur for a particular membrane feed water. Includes 31 references, figures.