Fouling of anion exchange resin by fluorescence analysis in advanced treatment of municipal wastewaters.

The application of anion exchange resins (AERs) has been limited by the critical problem of resin fouling, which increases the volume of the desorption concentrate and decreases treatment efficiency. To date, resin fouling has not been well studied and is poorly understood compared to membrane fouling. To reflect the resin fouling level, a resin fouling index (RFI) was established in this work according to the decrease of DOC removal after regeneration of the resin for the advanced treatment of municipal wastewater. Comparing the linear fitting results between the RFI and the fluorescence intensity indicated that the resin fouling was related to the protein-like substances with fluorescence peak T in the region of excitation wavelength <250 nm and emission wavelength <380 nm. Using their fluorescent characteristics as a label, the protein-like substances causing the fouling were further identified as hydrophilic components with molecular weights greater than 6500 Da.