Effect of chlorination disinfection on three-dimension fluorescence characteristic of DOM in secondary effluent
氯消毒对城市污水中DOM的三维荧光特性影响

During the process of chlorine disinfection of secondary effluent,continuous measurements of 3DEEM of secondary effluent DOM and the formation amount of THMs were used to investigate the relationship between variation of fluorescence matter and the formation amount of THMs,to infer the main precursors.The results showed that the fluorescence spectrogram of samples were varied with the time of 0~6 h after added NaClO,meanwhile the fluorescence intensity of each sample reduced by 40%~70%.It indicated that the reaction between DOM and chlorine disinfectant led to decrease the aromaticity and unsaturated rate of DOM,thereby lost their fluorescence characteristic.Particularly,the fluorescence intensity of aromatic protein(tyrosine-like),fulvic-like acid and humic-like acid changed apparently before and after chlorine disinfection reaction.That is to say these organic matters could be regarded as the principal THMs precursors.The formation amount of THMs increased obviously with reaction time,especially 15 min after reaction started the fluorescence intensity of DOM decreased about 50%,meanwhile 50.17% of total trichloromethane were formed.