The desired particle size should be able to settle to the bottom of the tank
WL - surface area of the tank A.
Q - throughout rate
Q = [ulim . A]
Above equation gives the maximum possible throughout for the desired particle size dlim having a sediment velocity ulim . From this it is observed that the height of the tank does not affect the throughput rate. Only alternative is throughput can be increased by increasing the surface area and it (surface area) can be increased by providing the horizontal or inclined plates in the tank as shown in figure 5.5b.
Q = ulim . N. A
Where N - number of separation channels of area A.
In the above equation ulim is fixed by the particle size and density, thus the throughput is proportional to total area N A.