This slide presentation outlines a study on measuring the inactivation kinetics of the ammonia oxidizing bacteria
(AOB) Nitrosomonas europaea in bench-scale
experiments in the presence of chlorine and
monochloramine,
generate CT values,
compare to E. coli CT value, and explore the disinfection kinetics of AOB in
the presence of corrosion debris, soil material,
and wastewater, comparing those results to
the kinetics obtained in pure water. A bench scale study is outlined in the presentation that had the following conclusions: in pure water, the use of free chlorine produced 6
logs of AOB inactivation at a CT value of 1.3
mg.min/L;
monochloramine yielded 4 logs of AOB inactivation at
a CT value of 10.5 mg.min/L;
the monochloramine inactivation kinetics of AOB are
similar to those of E. coli, but AOB are more resistant to chlorine than E. coli; and,
corrosion debris, soil material, and wastewater had
no statistically significant (p<0.05) impact on the
inactivation AOB. A second study is outlined with the objectives of:
at pilot-scale, monitoring AOB in the presence
of various disinfectants and source water
quality conditions,
varying specific ultraviolet absorbance (SUVA) and
bromide levels; and,
monitoring AOB levels at pilot-scale by using
the MPN cultivation method (25 to 30 days of
incubation) and a molecular method (PCR amplification of the amoA
gene). Study 2 conclusions included:
the testing phase with (high) 0.8-mg/L bromide, (high) >3.16 L
mg-1 m-1 SUVA is the only one during which HPC were detected
at the effluent of all treatment trains;
competition for chlorine between natural organic matter (NOM), bromide and microbial
inactivation may have affected disinfection;
however, AOB were not detected either by the MPN culture
technique or the molecular method in any of the phases;
nitrite concentrations were low, suggesting that nitrification did
not occur over the entire testing period, consistent with the absence of AOB in the simulated distribution systems;
adequate treatment prevents nitrification in distribution systems; and,
low HPCs suggest absence of AOBs. Includes tables, figures.
| Edition : | Vol. - No. |
| File Size : | 1
file
, 880 KB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 31 |
| Published : | 03/01/2007 |
