二级出水中亚硝胺类消毒副产物分布及臭氧化特性

Ozonation is usually applied to remove refractory organic matter from wastewater treatment plant (WWTP) effluent during wastewater reclamation, and improve the efficiency of downstream treatment process. Because of the effect of ozonation on nitrosamine disinfection by-products formation in WWTP effluent, the distribution and ozonation characteristics of nitrosamine disinfection by-products were investigated using solid phase extraction and UPLC MS/MS. The results show average concentrations of NPYR 250 ng•L^-1, NDIP 45.96 ng•L^-1, NDBA 31.17 ng•L^-1, NDMA 28 ng•L^-1, NMEA 4.92 ng•L^-1, NDPA 4.71 ng•L^-1 and NDEA 2.15 ng•L^-1 in the WWTP effluent. Furthermore, although ozone oxidation can increase the concentrations of nitrosamines in WWTP effluents, especially NPYR, NDIP, NDBA and NDMA, the nitrosamine formation potential decreases with the increase of ozone dosage. Moreover, the magnitude of reduction of the nitrosamine formation potential was more significant than its further increment. The difference between these two effects is more notable at high ozone dosages. Thus, ozonation can enhance the removal of the nitrosamine formation potential, which can reduce the formation of nitrosamine disinfection by-products during downstream advanced and disinfection processes to guarantee the safety of the reclaimed water.