COEFFICIENTS VERSUS NRe
1
Laminar
III
Turbulent
II
Transition
105
104
SPHERES
DISKS
103
CD
CYLINDERS
102
10
1.0
0.1
10-4
10-3
10-2
10-1
1
10
NRe
102
103
104
105
106
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.
SETTLING ZONE
V
INLET
v
V
vo
H
OUTLET ZONE
ZONE e
SLUDGE ZONE
Zones of a rectangular, horizontal, continuous-flow sedimentation basin.
2V
1/2 H
2V
v
vo
Reduced tank depth does not increase removal ratio.
V
1/2 H
V
v
1/2 v0
Intermediate
Tray
1/2 H
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 Wastes
25, no. 1 (1953): 1-12.
EFFECT OF PARTICLE AGGLOMERATION ON SETTLING
Settling
Zone
A
H
B
Figure by MIT OCW.
Adapted from: Camp, T. R. "Studies of Sedimentation Basin Design." Sewage and Industrial Wastes
25, no. 1 (1953): 1-12.
EFFECT OF TURBULENT DIFFUSION ON SETTLING
Figure by MIT OCW.
Adapted from: Camp, T. R. "Studies of Sedimentation Basin Design." Sewage and Industrial Wastes
25, no. 1 (1953): 1-12.
Apparatus For Quiescent Settling Analyses
Siphon
1
h2
Cock
Constant Temperature water bath
h5
3
Sample of Suspension
2
Portion for
concentration test
4
Sample of
suspension
5
Sludge
Figure by MIT OCW. Adapted from Camp, T. R., 1946. Sedimentation and the
design of settling tanks. Transactions ASCE. Vol. 111, Pg. 895-936.
R1
�h1
Sampling Ports
h1
�h2
Isopercent Removal Curves
�h3
DEPTH
h2
40%
50%
60%
70%
80%
h3
�h4
R5
R4
h4
R2
R3
0.5 m
150 mm
h5
t1
t2
t3
t4
t5
TIME
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.
RECTANGULAR SETTLING TANK
Sludge hoppers
Influent
Sludge
Drawoff
Drive motor
Skimmer
Chains
Scraper board
Scum
Scum
A
Effluent troughs
Effluent
Scum box
Plan
Drive
Skimmer
WS
Influent
Effluent
Sprockets
Chains
Scraper board
Sludge
Drawoff
Sludge hoppers
B
Longitudinal Section
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.
Flocculator
Clarifier
Corner
blade
Baffle
Walk way
Influent
channel
Blades
Effluent pipe
Weir
Rake arm
Cage Blade
Influent pipe
Sludge pocket
Drive Unit
Chain
Effluent
channel
Guide
plate
Flash mixer
Chamber
Counter weight
Paddle
Sheaves
Corner blade
Stuffing box
Sprocket
Chain
Dry well
Gear
motor
PLAN
Handrail
Diffuser
Water level
Concrete pier
Turntable
Cage
Top of tank
Rake arm
Flow
Baffle
Sludge discharge pipe
Flocculator & square sedimentation tank for water clarification, illustrating ceoss-flowoperation.
Figure by MIT OCW.
Adapted from: Droste, R. L. Theory and Practice of Water and Wastewater Treatment.
Hoboken, NJ: John Wiley & Sons, 1997.
Influent pipe
Effluent
Flume
Collection Trough
Bridg
e
Scraper Arm
Rotation
Flocculation Skirt
Mixer
Water level
Collection trough
with submerged
orifaces
Effluent flume
Flocculation zone
Settling zone
Settling zone
Inlet port
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.