Settling tanks, or settling tanks, are sand classifiers that work by the natural decay of sand particles within a stream of water. Water enters the tank from one end and flows to the opposite end, on the way the suspended sand grains decant starting from the largest to the smallest. This results in a distribution of sands with “coarser” grain size near the inlet and “finer” near the outlet.
The bottom of the tanks are made with conical bulkheads for collecting material, at the bottom of which are valves that discharge the deposited sand. This provides a classification of sands up to 100 microns in grain size.