105

104

103

102

10-4 10-3 10-2 10-1 102 103 104 105 106

II III1

10

10

1.0

0.1 1

NRe

CD

SPHERES

DISKS

CYLINDERS

Re

Laminar

COEFFICIENTS VERSUS N

Transition Turbulent

Figure by MIT OCW. Adapted from: Reynolds, T. D., and P. A. Richards. Unit Operations and Processes in EnvironmentalEngineering. 2nd ed. Boston, MA: PWS Publishing Company, 1996.

H

INLET

ZONE e

V v

vo

SETTLING ZONE

SLUDGE ZONE

OUTLET ZONE

V

Zones of a rectangular, horizontal, continuous-flow sedimentation basin.

2V

2V

Reduced tank depth does not increase removal ratio.

1/2 H v

vo

1/2 H

1/2 H

v 1/2 v0

Intermediate Tray

V

V

Tray in tank provides added floor area & increases solids removal

Figure by MIT OCW.

Adapted from: Camp, T. R. "Studies of Sedimentation Basin Design." Sewage and Industrial Wastes25, no. 1 (1953): 1-12.

A

B H

Settling Zone

EFFECT OF PARTICLE AGGLOMERATION ON SETTLING

Figure by MIT OCW.

EFFECT OF TURBULENT DIFFUSION ON SETTLING

Figure by MIT OCW. Adapted from: Camp, T. R. "Studies of Sedimentation Basin Design." Sewage and Industrial Wastes25, no. 1 (1953): 1-12.

Adapted from: Camp, T. R. "Studies of Sedimentation Basin Design." Sewage and Industrial Wastes25, no. 1 (1953): 1-12.

Siphon

Cock

Sample of suspension

Portion for concentration test Sam

ple of Suspension

Sludge

1

2

3

4

5

h5

h2

Con

stan

t Tem

pera

ture

wat

er b

ath

Apparatus For Quiescent Settling Analyses

�h1

�h2

�h3

�h4

h4

h3

t1 t2 t3 t4 t5

R5 R4 R3 R2

R1

h2

h1

h5

40% 50% 60% 70% 80%

TIME

DEP

TH

0.5 m

150 mm

Isopercent Removal Curves

Sampling Ports

Figure by MIT OCW.

Adapted from: G. Tchobanoglous, F. L. Burton, and H. D. Stensel. Wastewater Engineering:Treatment and Reuse. 4th ed. Metcalf & Eddy Inc., New York, NY: McGraw-Hill, 2003, p. 369.

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. 781.

Sludge

Sludge Scum Scum Scum box

Chains

Chains

Skimmer

Skimmer

Scraper board

Scraper board

Influent

Sludge hoppers

Sludge hoppers

Drive motor

Drive

Influent

Sprockets

B

A

Longitudinal Section

Plan

WS

Drawoff

Drawoff

Effluent

Effluent

Effluent troughs

RECTANGULAR SETTLING TANK

Figure by MIT OCW. Adapted from: Reynolds, T. D., and P. A. Richards. Unit Operations and Processes in Environmental Engineering. 2nd ed. Boston, MA: PWS Publishing Company, 1996, p. 249. ISBN: 0534948847.

Clarifier

Corner blade

Corner blade

Guide plate

Chain

Influent channel

Influent pipe

channel

Blades

Counter weight

Drive Unit

Cage Blade Rake arm

Flocculator

Flash mixer Chamber

Paddle

Chain Dry well

Sprocket Gear motor

Sheaves

Sludge pocket

PLAN

Walk way

Effluent pipe

Effluent

Weir

Baffle

Stuffing box

Rake armConcrete pier

Handrail

Influent pipe

Flow

Cage

Flocculator & square sedimentation tank for water clarification, illustrating ceoss-flowoperation.

Top of tank Diffuser

Water level

Baffle

Sludge discharge pipe

Turntable

Figure by MIT OCW.Adapted from: Droste, R. L. Theory and Practice of Water and Wastewater Treatment.Hoboken, NJ: John Wiley & Sons, 1997.

Rotation

Flume

Flocculation Skirt

Bridge

Collection trough

orifaces

Settling zoneSettling zone

Inlet port

Flocculation zone

Mixer

Collection Trough

Scraper Arm

Effluent

Effluent flume with submerged

Water level

Flocculator-clarifier provides mixing, flocculation, & sedimentation in a compartmented concentric circular tank.

Figure by MIT OCW.Adapted from: Droste, R. L. Theory and Practice of Water and Wastewater Treatment. Hoboken, NJ: John Wiley & Sons, 1997.

Figure by MIT OCW.Adapted from: Droste, R. L. Theory and Practice of Water and Wastewater Treatment.Hoboken, NJ: John Wiley & Sons, 1997.

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.