X. Zheng, M.T. Khan, J.P. Croue
Water Research, volume 65, 414-424, (2014)
Effluent organic matter, Fractionation, Characterization, Ultrafiltration, Fouling
EfOM has been regarded as a major organic foulant resulting in UF
membrane fouling in wastewater reclamation. To investigate fouling
potential of different EfOM fractions, the present study isolated EfOM
into hydrophobic neutrals (HPO-N), colloids, hydrophobic acids (HPO-A),
transphilic neutrals and acids (TPI), and hydrophilics (HPI), and tested
their fouling effect in both salt solution and pure water during
ultrafiltration (UF). Major functional groups and chemical structure of
the isolates were identified using Fourier transform infrared
spectroscopy (FT-IR) and solid-state carbon nuclear magnetic resonance (13C
NMR) analysis. The influence of the isolation process on the properties
of EfOM fractions was minor because the raw and reconstituted secondary
effluents were found similar with respect to UV absorbance, molecular
size distribution, and fluorescence character. In membrane filtration
tests, unified membrane fouling index (UMFI) and hydraulic resistance
were used to quantify irreversible fouling potential of different water
samples. Results show that under similar DOC level in feed water,
colloids present much more irreversible fouling than other fractions.
The fouling effect of the isolates is related to their size, chemical
properties, and solution chemistry. Further investigations have
identified that the interaction between colloids and other fractions
also influences the performance of colloids in fouling phenomena.
