The presence of taste and odors in drinking water is an increasingly frequent problem for water
utilities across Canada, the United States and the world. The earthy/musty odors produced by
geosmin and 2-methylisoborneol (MIB) are one of the most problematic types of taste and odors.
Both compounds are resistant to chemical oxidation and are difficult to remove by conventional
water treatment methods. Ozonation followed by biological filtration may offer an alternative
means of effective removal. In this research, bench scale experiments were conducted using four
parallel filter columns containing biologically active anthracite and granular activated carbon
(GAC) media and sand. The factors under investigation were temperature and media type. Source
water consisted of dechlorinated tap water to which geosmin and MIB were added as well as a
cocktail of easily biodegradable organic matter (i.e. typical ozonation byproducts) in order to
simulate water that had been subjected to ozonation prior to filtration. The results indicated that
both temperature and media (GAC vs. anthracite) were important factors. Temperature had a
significant effect on geosmin removals, especially in GAC filters. A decrease in temperature from
20oC to 8oC resulted in a decrease in removals as high as 37 percentage points. Media had a
significant effect on geosmin and MIB removals at both 20oC and 8oC. The difference in geosmin
removals between the two types of filters was much greater at 20oC (e.g. geosmin removals
reached a maximum of 30 percentage points higher in GAC filters than in anthracite filters). The
differences in MIB removals between the two types of filters was quite similar at both
temperatures. Includes 20 references, table, figures.
| Edition : | Vol. - No. |
| File Size : | 1
file
, 320 KB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 11 |
| Published : | 11/02/2003 |
