AWWA JAW22194

Dual-stage filtration (DSF) in packaged form is a good alternative to conventional rapid-rate filtration for small utilities. The purpose of the study described in this article was to test the effectiveness of DSF for removing Giardia cysts from low turbidity (<1 ntu), low temperature (near 32 degrees F [0 degrees C]) water. Removals of total coliform bacteria and turbidity were also determined. Two different water sources were tested, with runs up to 35 h in length. Dual-stage filtration removed >99 percent of Giardia cysts from water with a turbidity of <1 ntu and a temperature of <46 degrees F (<8 degrees C), when proper chemical treatment was applied and the system was operated at 10 gpm/sq ft (6.8 mm/s) or less. Removal of total coliform bacteria exceeded 98 percent, and removal of turbidity exceeded 90 percent. Includes 14 references, tables, figures.

Product Details

Edition:

Vol. 80 - No. 2

Published:

02/01/1988

Number of Pages:

10

File Size:

1 file , 2.2 MB