| Abstract
| - Various natural organic matter (NOM) constituents wereevaluated in terms of their biodegradability, disinfectionbyproduct (DBP) formation potentials, and membrane fouling.The biodegradability of NOM was evaluated with respectto biodegradable dissolved organic carbon (BDOC) andits inhibition control. NOM was divided into (i) colloidal andnoncolloidal NOM, using a dialysis membrane with amolecular weight cutoff of 3500 Da and (ii) hydrophobic,transphilic, and hydrophilic NOM constituents, using XAD-8/4 resins. The colloidal, and noncolloidal hydrophilic,NOM were identified as being more problematic than theother components, exhibiting relatively higher biodegradability and reactivity toward DBP formation potential. Ahigher biodegradability especially can provide a high riskof membrane biofouling, if a membrane is fouled byhighly biodegradable NOM. Colloidal, and noncolloidalhydrophilic, NOM constituents were also shown as majorfoulants of negatively charged membranes due to theirhigh neutral fractions. Filter adsorber (F/A) types of activatedcarbons were evaluated in terms of removals of NOM,DBP formation potential, and BDOC and were comparedto conventional processes and a nanofiltration membrane.The F/A process exhibited a comparatively good efficiency,especially in DBP and BDOC control, but was not so goodat removing NOM. This suggests that F/A could potentiallybe combined with a membrane process to minimize the DBPformation potential and bio-/organic-fouling (i.e., F/Aprocess as a pretreatment for a membrane process).
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