The Alameda County Water District, located in Fremont, California operates a 28-MGD water
treatment plant that uses preozonation for disinfection, oxidation, and taste-and-odor control.
The plant treats Sacramento-San Joaquin Delta water, which periodically contains high levels of
bromide. High bromide levels lead to the formation of bromate upon ozonation of this water. In
2002, the District installed a carbon dioxide (CO2) feed system to lower the pH of the water
upstream of ozonation in order to reduce bromate formation. Preliminary results show that bromate formation with ozonation
can be significantly reduced by the addition of carbon dioxide (CO2). The focus of this paper is
on the performance of the CO2 system and efforts made by the project team to analyze and
optimize its operation. Topics covered include: plant description; bromate minimization; direct vs indirect feed method; CO2 stripping in last chamber of contactor; and, impact on chemical doses. Includes 2 references, tables, figures.
| Edition : | Vol. - No. |
| File Size : | 1
file
, 310 KB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 10 |
| Published : | 06/15/2003 |