Fractionating natural organic matter and evaluating the fouling potentials of its components

This study was to fractionate natural organic matter (NOM) and evaluate the fouling potentials of its components in a pilot-scale microfiltration process. NOM in the feed water was fractionated into strongly hydrophobic acids (SHA), weakly hydrophobic acids (WHA), charged hydrophilic acids and neutral hydrophilic acids (NEU) fractions by resin adsorption; each fraction was then subdivided into low molecular weight (<1 kDa; LMW), medium molecular weight (1–10 kDa, MMW) and high molecular weight (10–10 4 kDa, HMW) components via high-performance size exclusion chromatography coupled with peak-fitting. Principal component analysis and Pearson correlation analysis demonstrated that hydraulically irreversible fouling index significantly correlated to NEU–MMW (R 2 = 0.787, p value = 0.001), SHA–LMW (R 2 = 0.927, p value < 0.0001) and WHA–LMW (R 2 = 0.899, p value < 0.0001). Fouling control strategy should be targeted at removing these foulants.