A survey conducted in more than 800 utilities in the United States and Canada
had found that 16% of the utilities experience serious taste and odor problems. The earthy and musty odor in surface water is frequently caused by 2-
methyisoborneol (MIB) and Geosmin. These compounds are produced by blue green algae or
actinomycetes metabolites and can be detected in drinking water at very low
concentrations (Gerber 1965; Rosen 1970; Suffet et al. 1995). The threshold
concentration for detecting these compounds depends on the taste and odor sensitivity of
the individual and it varies from about 6-10 ng/L (Meng and Suffet 1997; Rashash et al.
1997; Wnorowski 1992). Incorporating processes in water treatment plants that
effectively remove MIB and Geosmin should also achieve other treatment goals such as
microbial or disinfection byproduct (DBP) control.
Activated carbon processes are commonly used to remove MIB and Geosmin, but
some oxidation processes are also quite effective (Bruce et al. 2002; Graham et al. 2000).
Past studies focused primarily on ozone dose and percentage
MIB or Geosmin removal. This paper focuses on the mechanisms and kinetics
of MIB and Geosmin oxidation.
Although ozonation is very effective in removing MIB and Geosmin, the lack of
information on oxidation mechanisms (O3 vs OHA radicals) prevents optimization of
ozone for taste and odor control, DBP control and microbial control. The goal of this
paper is to understand the relative importance of O3 and HOA oxidation pathways and rate
constants for MIB and Geosmin. Kinetics were evaluated for MIB and Geosmin
oxidation by ozone in natural waters with a range of water qualities. Effects of various
treatment process parameters (ozone dose, pH, H2O2) and water quality parameters
(temperature, initial MIB concentration) were evaluated. Additional treatment
considerations (BDOC formation, bromate control and microbial inactivation) were
evaluated in light of achieving MIB and Geosmin removal. Includes 31 references, figures.
| Edition : | Vol. - No. |
| File Size : | 1
file
, 310 KB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 9 |
| Published : | 11/02/2003 |
