The turbidity spike that occurs during filter ripening
can be minimized without additional equipment or
chemicals, simply by optimizing backwash steps. However,
filter-to-waste (FTW) is still needed to achieve
aggressive filter effluent turbidity targets.
A study was undertaken at the Central Lake County
Joint Action Water Agency in Lake Bluff, Illinois, to minimize
water consumption and maximize filter service
life. Filtration and water use were optimized using
existing equipment and a method called extended terminal
subfluidization wash, demonstrating that
10-year-old biologically active granular activated carbon
is still viable. The FTW peak following backwash
was reduced from an average of 0.13 to 0.08 ntu.
In addition, results suggest that FTW is not required
in 96% of filter backwashes. Therefore, automatic
FTW following backwash should be discontinued and,
instead, FTW should only be used as needed. Includes 54 references, tables, figures.
| Edition : | Vol. 99 - No. 5 |
| File Size : | 1
file
, 440 KB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 10 |
| Published : | 05/01/2007 |
