Ozonation of waters containing moderate to high levels of bromide, such as California State
Project Water, can form bromate at levels that may exceed the maximum contaminant level of
10 µg/L. A proven technology to minimize the formation of bromate is to reduce the pH of
ozonation (typically acidic). However, in waters with moderate or high alkalinity, the cost of
acid and caustic addition to lower and subsequently raise the pH of the water can be higher than
the operating cost of ozone production alone. To lower costs, the Metropolitan Water District of
Southern California has been conducting a long-term evaluation of the addition of ammonia and
then chlorine to form chloramines prior to ozonation as an alternative bromate control strategy.
The primary objective of the study was to determine the effectiveness of the "ammonia-chlorine"
process as a bromate control strategy while minimizing the formation of other disinfection byproducts
of concern. This paper provides new insights into an emerging bromate control
strategy, as well as a potential fatal flaw, the increased formation of N-nitrosodimethylamine in
treated water. Includes 22 references, table, figures.
| Edition : | Vol. - No. |
| File Size : | 1
file
, 1.8 MB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 41 |
| Published : | 11/01/2009 |
