AWWA JAW56639 Journal AWWA - Effects of Filter Operation on Cryptosporidium Removal

Journal Article by American Water Works Association, 06/01/2002

Huck, Peter M.; Coffey, Bradley M.; Emelko, Monica B.; Maurizio, Danielle D.; Slawson, Robin M.; Anderson, William B.; Van den Oever, John; Douglas, Ian P.; O'Melia, Charles R.

Full Description

Physicochemical removal of protozoan pathogens is receiving increased attention becauseof the difficulty of chemically inactivating these organisms, particularly Cryptosporidiumparvum. Most research examining the removal of these and other pathogens by filtration hasbeen conducted under steady-state conditions with optimized pretreatment. This studyevaluated the removal of Cryptosporidium and changes in surrogateparameters at various points in the filter cycle and under nonoptimalconditions at two pilot plants with different coagulation regimes.The study found a reproducible 2-log difference in Cryptosporidiumremovals between the two locations under optimal conditions, withsimilar low effluent turbidity levels and particle counts. Eithersuboptimal coagulation or the early stages of breakthrough at the end of a filter run producedsubstantial deterioration of Cryptosporidium removal capability. Filter ripening or the impositionof a hydraulic step generally had much less effect on removals. Includes 37 references, tables, figures.

Product Details

Edition: Vol. 94 - No. 6 Published: 06/01/2002 Number of Pages: 15 File Size: 1 file , 380 KB