AWWA WQTC60589

Microorganisms have been shown to survive drinking water disinfection and remainviable in disinfected waters despite the presence of disinfectant residuals. This may bepartially due to protection by particulate matter. This paper studies theeffects of the presence of particulate matter on disinfection kinetics in comparison tokinetics in particle-free water. Heterotrophic plate count bacteria and Helicobacter pyloriwere used in inactivation experiments in the presence and absence of soil, corrosion, andwastewater particles. Inactivation of indicator organisms, namely Bacillus subtilis sporesand MS2 phages, was also studied using synthetic, demand-free buffered water, in thepresence and absence of floc particles. Floc particles were produced using kaolin clayand alum in an attempt to entrap the organisms. The disinfectants assessed in this studyinclude UV, free chlorine, chlorine dioxide, and monochloramine. Results showed thatthe mere presence of the soil and corrosion particles in the water could affect theinactivation kinetics, decreasing the level of inactivation by up to 1 log in some cases,compared to particle-free water for the same CT. Wastewater particles and coagulatedkaolin clay had no effect on microbial inactivation with the disinfectants used in thisstudy. Includes 17 references, tables, figures.

Product Details

Edition:

Vol. - No.

Published:

11/15/2004

Number of Pages:

13

File Size:

1 file , 410 KB