Research On Typical Antibiotics Distribution Of Drinking Water Treatment Processes

In recent years, the problem of QNs residue in water environment attracted great attention of the domestic and overseas researchers. It was reported that QNs were detected in some rivers and tap waters in our country. DWTPs play a key role in preventing QNs from drinking water. Hence, it is of great significance to establish a accurate and highly efficient method to detect the concentrations of QNs in drinking water treatment processes. It can ensure the safety of drinking water.In our research, SAR, OFL, ENR, CIP, NOR, and PIP were choosed as targeted contaminants. Simultaneous determination of QNs in drinking water treatment plant of A, B and C using solid phase extraction and ultra-performance liquid chromatography-tandem mass spectrometry. And then the elimination efficiencies of the drinking water treatment processes were systematically evaluated.First, the standard solution was used to optimize ultra-performance liquid chromatography and mass spectrometry conditions. The quantification ion and confirmation ion were obtained. And then the preservation condition of water samples, condition agent, flow rate, rinse agent, elution and the volume of extraction were optimized to achieve the demand of the high enrichment, good purification effect, high recoveries. The recoveries ranged between72%~84%and80%~118%for deionized water samples, spiked at50and100ng/L, and the relative standard deviations were between0.2%~13%and1%~4%. The recoveries ranged between60%~120%and80%~104%for processes samples, spiked at20and50ng/L, and the relative standard deviations were between2%~20%and0.4%~11%.The concentrations of QNs in A, B and C DWTPs were detected. Our research detected the concentrations of QNs in Songhua river and Yellow river for the first time. The source waters were100%detected except for LOM in three DWTPs. The concentrations of particle QNs had a relationship with turbidity and the concentrations of QNs in source water. The particle QNs can be all removed during processes, however resolvable QNs can be removed difficulty. The elimination efficiencies of QNs were limited during conventional water treatment processes. The preoxidation process played a dominant role, however the effects of coagulation, sand filtration and chlorination were not obvious. The effects of ozonation-activated carbon were not good. The effects of different processes have a relation ship with raw water and operation parameters of DWTPs, and have a different in different periods.