13

1

/l

2

c

o o

10

10 100 100

1.0

0.10

0.01

Chl

orin

e C

once

ntra

tion,

mg

HOCl

OCl-1

NH Cl

Minutes, t

Concentration versus contact time for 99% kill of E. coil by various forms of chlorine at 2 C to 6 C.

Figure by MIT OCW.

Figure by MIT OCW.

1

/l

c

o o

Adenovirus 3

E.coli Poliomyelitis virus 1

Coxsackie virus A2

0.1

0.1

10 100

1.0

0.01

Chl

orin

e as

HO

CL,

mg

Minutes, t

Concentration versus contact time for 99% kill of E. coil and three enteric viruses by HOCl at 0 C to 6 C.

Adapted from: Reynolds, T. D., and P. A. Richards. Unit Operations and Processes in EnvironmentalEngineering. 2nd ed. Boston, MA: PWS Publishing Company, 1996, pp. 742-743.

Required C.t or l.t Combined chlorine Free chlorine Chlorine dioxide Ozone UV light

C. parvum

Legionella Mycobacterium fortuitum

Poliovirus

E. coli

E. coli

E. coli

Ade

novi

rus

Ade

novi

rus

Adenovirus

Adenovirus

Adenovirus

Cal

iciv

irus

Cal

iciv

irus

Calicivirus

Cal

iciv

irus

C. parvum

C. parvum

C.parvum

M.fortuitum

Legionella

Legionella

Microsporidium

Microsporidium

Microsporidium

Giordia Poliovirus

Polio

viru

s

Poliovirus

M.fortuitum Hepatitis A

Rotavirus

0.01

0.10

1.0

10

100

1,000

10,000

Giardia

E. coli

E. coli Legionella pnuemophila

Cal

iciv

irus

Giardia

M.fo

rtuitu

m

Poliovirus

Legionella Giardia Giardia

Reovirus MS-2

C.parvum

Overview of disinfection requirements for 99 percent inactivation.

Figure by MIT OCW.

Adapted from: MWH, J. C. Crittenden, R. R. Trussell, D. W. Hand, K. J. Howe, and G. Tchobanoglous.Water Treatment: Principles and Design. 2nd ed. Hoboken, NJ: John Wiley & Sons, 2005, p. 1063.

2 j

Sensor

Cl In ection

Sulfite Diffuser

Chlorination - Dechlorination Controller

Alternate Locations for Sensor

Typical contact chamber for chlorination. Baffles are provided to promote plug flow. When chlorine has been applied at elevated concentrations, sulfite is added to reduce chlorine to levels that will not cause consumer reaction to chlorine taste and odor.

Figure by MIT OCW.

Adapted from: Binnie, C., M. Kimber, and G. Smethurst. Basic Water Treatment. 3rd ed. Cambridge, UK: Royal Society of Chemistry, 2002.

Figure by MIT OCW.

Adapted from: MWH, J. C. Crittenden, R. R. Trussell, D. W. Hand, K. J. Howe, and G. Tchobanoglous.Water Treatment: Principles and Design. 2nd ed. Hoboken, NJ: John Wiley & Sons, 2005, p. 1121.

Chris Johnson

Text Box

Clements, John, 2004. Ultraviolet Disinfection. Brown and Caldwell Engineers. February 2004. http://www.xaraxone.com/FeaturedArt/jc/html/08.htm Accessed 3/13/05

Figure by MIT OCW. Adapted from: Mancl, Karen M.. "Bacteria in Drinking Water." The Ohio State University Extension Bulletin. Bulletin 795 (1989).