Flocculation is when the concentration of sediment is high enough for the sediment flocs to influence each other’s settling velocity. This happens because collisions between flocs will increase floc size leading to higher settling velocities.
Standard flocculation concentrations occur when hindered settling is neglected. The calculation is shown in Figure 7.2.
Figure 7.2 Applied concentration profile when flocculation selected
|
rsediment |
Density of grain material |
|
cfloc |
Concentration at which flocculation begins |
|
ctotal |
Total concentration of sediment (sum of concentrations of all fractions) |
|
chindered |
Concentration at which hindered settling begins |
|
Ws |
Settling velocity |
|
W0 |
Settling velocity coefficient |
|
g |
Power constant |
