AWWA WQTC60675

This research evaluated the efficiency of biological treatment in the presence of typical easilybiodegradable ozonation byproducts and in their absence in removing or minimizingconcentrations of geosmin and MIB. Bench scale experiments were conducted using four parallelbiofilter columns in which two columns contained exhausted granular activated carbon (GAC)media and sand, and two columns contained fresh anthracite and sand. Source water consisted ofdechlorinated tap water to which geosmin and MIB were added, as well as a cocktail of easilybiodegradable organic matter (BOM, i.e. typical ozonation byproducts). Phase I experimentsinvestigated a high BOM level (280 mg/L) in order to simulate water that had been subjected toozonation prior to filtration, while Phase II experiments used a low BOM level (28 mg/L) tosimulate a non-ozonated water. Analysis of the data showed that percent removals of these odorcompounds in both Phases I and II were measurably higher in the columns containing the GACmedia. Comparable removals of both odor compounds were observed between the simulatedozonated water and the non-ozonated water when GAC media was used. Geosmin percentremovals in these columns ranged between 55-70% where upstream ozonation was simulated andbetween 47-69% where there was no upstream ozonation. MIB percent removals in thesecolumns ranged between 23-49% where upstream ozonation was simulated and between 29-40%where there was no upstream ozonation. In the case of anthracite media, removals of both odorcompounds were substantially lower when there was no simulation of upstream ozonation.Biomass levels in the filters appeared to have a major impact on the removal efficiencies of bothodor compounds. Includes 17 references, figures.

Product Details

Edition:

Vol. - No.

Published:

11/15/2004

Number of Pages:

56

File Size:

1 file , 1.8 MB