The Characteristics Of Bbps Formation And The Related Removed Technique For Qiantang Sources Water

Disinfection by-products (DBPs) in drinking water have been a great threat to human health, so understanding the rule of DBPs formation and finding the effective measure to control DBPs have becoming a public concern. The Puprose of this thesis was to1) explore the DBPs formation characteristics and the control technology of qiantang river after chlorination or chloramination.2) investigate the effects of NO2-to HNMs formation under different disinfection conditions (take tryptophan as anexample).3) characterize the hydrophilic and hydrophoblc features of organic matter from different sources, and associate DBPs formation. The main conclusions were as following:1. For some water workers that take qiantang river water as source water, chloramination was an effective way to control the formation of THMs、HAAs、HKs and HAN, But not for HNMs.2. The yields of THMs、HAAs、 HANs and HNMs increased with the increasing of bromide ions concentration and reaction time after chlorination and monochlorination. Other impact factors have different influences on the generation of DBPs. In chlorination, THMs、THAAs、DHAAs and HNMs increased with temperature. As for the influence of pH, the formation of THMs、THAAs、DHAAs and HNMs facilitated by the alkaline condition, yet opposite was true for HANs. During chloramination, the yields of THMs、 THAAs、DHAAs and HNMs was higher in acid condiction, while for HNMs, pH exacted no obvious effect on its formation. Additionlly, the temperature increases with the increasing of temperature enhanced the formation of HNMs, while have no effect on THMs、THAAs and DHAAs. 3. The nitrite ion promoted the formation of TCNM obviously. In chlorination, the promotion of TCNM formation in acid condition was more significantly than in alkaline; yet opposite was true for chloramination. However, whether for chlorination or chloramination, the facilitation of TCNM formation resulting from nitrite addition was increased with the chlorine/chloramine dose and reaction time.4. The acid hydrophobic OM was the most fraction both for the allochthonous OM and autochthrous OM. The neutral-alkaline hydrophobic OM and hydrophilic OM were relative smaller. Also the results showed that the precursors of THMs and HAAs tend to be hydrophobic in nature; while for HANs, both the hydrophobic and hydrophilic were the potent precursors. Different from THMs-. HAAs and HANs, the precursors of HNMs dominated by the hydrophilic OM, the neutral basic-hydrophobic OM also produced appreciable amount of HNMs.5. PAC、MIEX as well as the AC could remove the organic matter (TOC and UV254) from qiantang source water to some extent. Overall, the above technique also reduced the THMs yields effectively, yet for HNMs, AC showed the removal effect, followed by MIEX, and the leasted was PAC.