預臭氧加氯程序中Trimethoprim , Sulfamethoxazole及 Diclofenac 之含氮消毒副產物生成探討

Abstract

Water pollution degrades environmental quality and adversely impacts public health. PPCPs are one of the pollutants which may contribute adverse impact to our environment. Diclofenac is a nonsteroidal anti-inflammatory , Sulfamethoxazole and Trimethoprim are the antibiotic. This three drugs was usually detected in surface water. In this research , ozonation was used as a pre-treatment process to oxidize the nitrogen containing PPCPs. The UV254 absorbance (or SUVA) , which is proportional to the aromatic content of water , was selected as an indicator for organic compound and DBPs formation. The effects of pre-ozonation on the formations of haloacetonitriles , trichloronitromethane and the haloketones were investigated in this study. The pre-ozonation dosages used in this experiment were 2.4mg/L ,4.8mg/L and 7.2mg/L , respectively. Results show that higher ozone dosage would increase the formation rate of DBP and elevate the maximum DBP concentration to a higher level during the 7 day chlorination process. However , it was found that DCAN , DCP , TCP decay rapidly with increasing ozone dosages levels. Chloroform , a hydrolysis byproduct of other DBPs , was the major DBP species in the pre-ozonation plus chlorination processes. Chloroform was formed rapidly during the chlorination process and steadily maintain its maximum concentration. TCNM , the most concerned nitrogen containing DBP was chosen as an indicator to evaluate the pre-ozonation effect. The formation trend of TCNM was studied and was found to be similar to that of chloroform. The concentration of TCNM was increasing with the pre-ozonation dosages level. In this research , the pre-ozonation is recommended to be the treatment technology to treat the Diclofenac , Sulfamethoxazole and Trimethoprim in drinking water treatment process. But the DBPs formation (like TCNM ) would cause the risk which need to consider in the further study