Formation potentials of typical disinfection byproducts and changes ofgenotoxicity for chlorinated tertiary e uent pretreated by ozone
CAO Nan , MIAO Tingting , LI Kuixiao , ZHANG Yu , YANG Min
DOI:
Received May 12, 2008,Revised June 16, 2008, Accepted , Available online
Volume 21,2009,Pages 409-413
- Summary
- References
- Related Articles
The e ects of ozonation on the formation potential of typical disinfection byproducts (DBPs) and the changes of genotoxicity during
post chlorination of tertiary e uent from a sewage treatment plant were investigated. Ozonation enhanced the yields of all detected
chlorine DBPs except CHCl3. At a chlorine dose of 5 mg/L, the three brominated THMs and five HAAs increased, while chloroform
decreased with the increase of ozone dose from 0 to 10 mg/L (ozone dose in consumption base). At a chlorine dose of 10 mg/L, the two
mixed bromochloro species THMs and two dominant HAAs (DCAA and TCAA) increased firstly and then decreased with the increase
of ozone dose, with the turning point approximately occurring at an ozone dose of 5 mg/L. The genotoxicity detected using umu test,
on the other hand, was removed from 7 g 4-NQO/L to a negligible level by ozonation under an ozone dose of 5 mg/L. Chlorination
could further remove the genotoxicity to some extent. It was found that SUVA (UV absorbance divided by DOC concentration) might
be used as an indicative parameter for monitoring the removal of genotoxicity during the oxidation.
