AWWA JAW27618

The removal of Giardia cysts by three small (0.01 to 0.57-mgd) treatment plants--one with conventional filtration, one with in-line filtration, and one with diatomaceous earth filtration--was studied. Turbidity and cyst removals for each were compared with those of parallel pilot filters (1 gpm) seeded with Giardia cysts and with and without optimization of chemical treatment. Cyst removal efficiencies ranged from about 40 to 99 percent. Design and operating deficiencies likely contributed to the observed treatment performances. Major deficiencies included lack of or poor optimization of chemical treatment, on-off cycles of filters without backwashing, absence of operator control of backwashing, and no filtering to waste. Includes 25 references, tables, figures.

Product Details

Edition:

Vol. 82 - No. 6

Published:

06/01/1990

Number of Pages:

12

File Size:

1 file , 2.2 MB