This study evaluated the potential of ozone-assisted biofiltration (OAB) for removing taste and odor
(T&O) compounds. OAB is a two-step process. In the first step, ozone is added to
breakdown the natural organic matter (NOM) into bioassimilable organic carbon. In the
second step, biologically active filters are used to oxidize the bioassimilable organic
carbon. Pilot testing of OAB was conducted at the Chandler Water Treatment Plant in Arizona as
part of an American Water Works Association Research Foundation (AWWARF) study.
In these pilot studies, granular activated carbon (GAC)/sand and anthracite/sand media
were evaluated parallely. To reduce removal by adsorption, exhausted GAC was used in
the GAC pilot filters. The results showed higher 2-methyl isoborneol (MIB) removals in filters with GAC/sand
media compared to anthracite/sand. The MIB removals were a function of empty-bed
contact time (EBCT); higher MIB removals were observed in filters with higher EBCTs.
Most of the MIB removal occurred in the top few inches of the filters indicating
predominance of biological oxidation in the upper layers of the media. Increasing ozone
dose resulted in slightly enhanced MIB removal. The GAC/sand filters outperformed
anthracite/sand filters in terms of total organic carbon (TOC) and UV254 reductions. Higher heterotrophic plate counts (HPCs) were
observed in GAC/sand filters compared to anthracite/sand filters indicating higher
bioactivity in GAC/sand filters. Both GAC/sand and anthracite/sand filters produced
water with turbidities less than 0.2 NTU. Includes 5 references, figures.
| Edition : | Vol. - No. |
| File Size : | 1
file
, 900 KB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 14 |
| Published : | 06/15/2003 |
