AWWA WQTC64130

The capacity of biological filtration to control taste and odor (T&O) is not wellunderstood. The microbial metabolic byproducts, 2- methylisoborneol (MIB) andgeosmin, present in many surface waters, are thought to be the most common source ofT&O. Seven parallel filters were run at an empty bed contact time of 7 min, 6 withacclimated media, both sand (BAS) and granular activated carbon (GAC), and one withnon-acclimated sand. The GAC had been in use for about 10 months and the sand hadbeen in use for at least 2 years. One BAS filter was run at 5 ºC and all others at 20 ºC.Geosmin and MIB were initially spiked in at a target concentration of 100 ng/L. Afterfour months of operation, the MIB removal in the three pre-acclimated BAS filtersaveraged 46 % removal at the lab temperature, while nearly no removal (<5 %) wasfound at 5 ºC with the pre-acclimated BAS. After four months the un-acclimated sand in5 averaged <10 % removal. The MIB removal in the BAC columns was about 65%,higher than that with BAS at lab temperature. After four months of operation theconcentration in all filters was increased to 200 ng/L for two weeks and the removalpercent remained the same. Includes 2 references, tables, figures.

Product Details

Edition:

Vol. - No.

Published:

11/01/2006

Number of Pages:

8

File Size:

1 file , 390 KB