AWWA JAW20092

The primary objective of this research was to determine whether results obtained with laboratory-scale rapid rate filtration of low turbidity waters could be duplicated during full-scale operation. Specific objectives were to ascertain removals of Giardia cysts, total coliform bacteria, and turbidity, to ascertain the efficiency of rapid rate filtration at water temperatures approaching 32 degrees F (0 degrees C), and to determine empirical relationships between filtered water turbidity and coagulant dose for low turbidity ambient water conditions. Results indicate that research findings using pilot filters are applicable to full-scale plants because the only difference is in the bed area-perimeter relationship. The rapid rate filtration process was found to remove high percentages of microscopic particles, as measured by percent reductions in turbidity, bacteria, and Giardia cysts, when operated with proper chemical coagulation. Rapid rate filtration of low turbidity water was found to be as efficient at 32 degrees F (0 degrees C) as at higher temperatures, if proper chemical coagulation is practiced. Recommendations are presented for assuring the removal of Giardia cysts and other microscopic particles at fullscale treatment plants when low turbidity waters are being treated. Includes 9 references, table, figures.

Product Details

Edition:

Vol. 78 - No. 12

Published:

12/01/1986

Number of Pages:

10

File Size:

1 file , 2.5 MB