AWWA ACE68640

This powerpoint presentation begins by providing a brief overview of pathogen disinfection research inwater network biofilms, along with pathogen surrogates, unique research aspects ofpathogen adhesion tobiofilm, and chlorine dioxide as analternative disinfectant. The objectives of this research were to: develop a correlation between chlorine andchlorine dioxide during disinfection of B. globigii;determine the CT values at different concentrationsneeded to reach 1, 2 and 3 log reductions;identify the CT_lag value that each disinfectantrequires to overcome mass transfer limitationsdue to its properties at the specified disinfectionpH and spore surface charge by using thedelayed Chick-Watson model; and, determine the effect of exposure time andconcentration on the inactivation rate. Initial experiments consisted of the following:model distribution system was a Biofilm AnnularReactor (BAR) with iron coupons;surrogates were pulse injected(lebsiella pneumoniae (Burkholderia mallei) andBacillus globigii (Bacillus anthracis)); and, theobjective was to determine the disinfection of theseorganisms in biofilms growing on rusted ironusing chlorine. Topics presented include: preliminary B. globigii disinfectionresearch with chlorine; bulk disinfection experimentresults; delayed Chick Watson Model; Watson Plot Analysis; Watson Plots for bulkexperiments; biofilm development; biofilm disinfection WatsonPlots; chlorine dioxide results; cement and cement-lined pipe; results relative tocast iron pipe; and, concrete pipe conclusions. Includes figures.

Product Details

Edition:

Vol. - No.

Published:

11/01/2008

Number of Pages:

35

File Size:

1 file , 2.6 MB