C-, N-DBP formation and quantification by differential spectra in MBR treated municipal wastewater exposed to chlorine and chloramine

The differential log-transformed UV spectral parameters including DLnA350 (differential logarithm of absorbance at 350 nm) and DSloop300-340 (slope differential of the log-transformed spectra at wavelength range 300-340 nm), and differential Excitation/Emission Matrix (EEM) fluorescence spectral parameters including DI(λ280λ310) (differential fluorescence intensity for proteins) and DΦi,n (i = T, II and III; differential of integrated EEM intensities for gross DOM, humic acid-like and fulvic acid-like components) had strong exponential correlations to THM4 formation (R2 > 0.99) and linearly correlated to HAN4 yield during disinfection of MBR effluents. It indicated that THM and HAN formation was related to the halogenation of proteins and humic substances. No quantitative correlation was found between NDMA yields and the studied spectroscopic parameters.