Page 660 - Fundamentals of Water Treatment Unit Processes : Physical, Chemical, and Biological

Disinfection 615

TABLE 19.3
Ct Data for Various Microorganisms and Disinfectants for 2-log (99%) Kill
Conditions Disinfectant
Microorganism pH T (8C) Chlorine Chloramine Ozone ClO 2
Bacteria
HPC 2 a 102 b
a
E. coli 1 =0.2 a 50 c
6.0 5 0.04 d
d
10.0 5 0.92 (OCl )
4.5 15 5.5 (NHCl 2 ) e
e
9.0 5 175 (NH 2 Cl)
9.0 15 64 (NH 2 Cl) e
9.0 25 40 (NH 2 Cl) e
7.0 12 0.001 f
7.2 1 0.02 f
6.5 5 0.41 g
Bacillus anthracis 7.2 0–5 400 a
7.2 20–29 100 a
S. dysenteriae 7 20–29 0.5 a
Viruses
Adenovirus 3 0.01 h
h i
Polio 1.0 0.9
Polio 1 6.0 5 1.0 d
7.0 5 6.0 g
9.0 5 1420 c
9.0 15 900 (NH 2 Cl) e
7.2 5 <0.04 f
7.0 25 0.42 f
Coxsackie A9 6.0 5 0.14 d
7.0 15 0.4 g
Coxsackie B5 6.0 5 1.7 d
7.8 5 2.2 d
f
7.0 25 0.53
Echo 1 6.0 5 0.24 d
d
10.2 5 48 (OCl )
7.0 25 0.44 f
Hepatitis A virus 6.0 5 0.50 j
7.0 5 0.70 j 0.2 j
8.0 5 296 c 0.50 j
Rotavirus
MS-2 bacterioph. 6–9 <1 6 j 2535 j 0.9 j 8.4 j
Cysts
k
G. lamblia cysts 7.0 <1 289 =140 j 1243 j 1.9 j 42 j
l
C. parvum est. 7000
6–11 1 606 m
m
5 442
13 230 m
22 111 m
6–8 10–27 5.0 n
(continued)