A demonstration-scale study was undertaken to evaluate
pH suppression and ammonia addition to
control bromate formation under disinfection
conditions for Cryptosporidium. Specific research
objectives included determining the effects of seasonal
bromide changes on bromate formation over a range of
pH values and assessing control of bromate over a
variety of ammonia doses, at varying disinfection levels,
and at different pH values.
Tests were conducted on two sample waters with
varying levels of alkalinity, bromide, and total organic
carbon. Although pH control did limit bromate formation,
the strategy was found to be relatively expensive
because of the large chemical dosages required. As a
bromate control method, ammonia proved source
water-specific, with a higher rate of success in high-alkalinity
waters than in those with lower alkalinity.
Furthermore, ammonia addition must be carefully
balanced with the need to provide secondary disinfection
with chlorine or chloramines.
Many water suppliers in the southwestern United
States rely on the source waters tested in this work or
are using water with moderate-to-high bromide levels.
This research offers direction, practical guidance, and
cost analyses for utilities that are considering using
ozone or changing their existing ozone practice. Includes 37 references, tables, figures.
| Edition : | Vol. 95 - No. 10 |
| File Size : | 1
file
, 290 KB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 12 |
| Published : | 10/01/2003 |
