AWWA ACE63142

The specific objectives of this research included:ranking the relative importance of various media characteristics and operationalconditions on biofiltration removals of E. coli bacteria;assessing the effect of a sudden removal of the schmutzdecke on pathogenremoval in the event of scouring or cleaning and a filter's ability to recover fromsuch an event;comparing the role of protistan predation to that of adsorption and straining as apathogen removal mechanism; and,determining the extent to which biological activity contributes to pathogenremoval in a biological filter. Specifically, do the extracellular polymericexcretions of the biofilm present in drinking water treatment enhance the"stickiness" of filter media?Methods includedsix studies conducted on laboratory scalesand columns under varying operational and design conditions withspiked concentrations of E. coli to assess removal efficiency. Results confirmed that E.coli removals in slow-rate biological filters occur primarily at the interface. These interfacialremovals appear to be related to schmutzdecke ripening state, empty bed contact time,biological activity, temperature, and protistan abundance. Includes 11 references, tables, figures.

Product Details

Edition:

Vol. - No.

Published:

06/01/2006

Number of Pages:

15

File Size:

1 file , 280 KB