This system is also called a decanter / thickener. It is a device that performs two functions: clarify the waters loaded with suspended solids and also thicken the sludge that is formed as a result of settling.
The system consists of a cylindrical tank with a lateral height of between 3 and 4 meters and a variable diameter (depending on the flow rate and the specific characteristics of the specific characteristics of the water to be treated), a pre-supply tank where the raw water is deactivated and mixed with flocculant, a central cylinder where the raw water already flocculated is distributed in the main tank through the bottom of it. And a gutter in the upper part of the perimeter of the tank, with V-shaped notches that allow a controlled evacuation of the clarified water. In this way, the sludge settles to the bottom and is regularly extracted by a central cone by means of a mechanism that rakes the entire surface of the bottom and sends the decanted sludge to the central well.
The control head that operates the raking mechanism has a force meter so that when the concentration of the sludge is the desired one, the extraction of the same takes place.
In this type of equipment, a blade lifting mechanism is installed, so that in cases of overload, the sludge can be freed and progressive sludge extraction begins.