A surface aerator is employed for the sufficient supply of oxygen to the wastewater for the deliberate degradation of carbon and for the nitrification. The surface aerator designed to float and thus matches itself at all times to the changing to every filling level. This ensures an optimum oxygenation performance with every filling height of the SBR tank. A further advantage of the surface aeration are the very simple maintenance tasks to be carried out, which can be executed without taking the SBR tank out of service.
Following completion of the actual wastewater treatment and ending of the sedimentation phase the clarified water is drawn off from the clarified water zone of the SBR tank using a clarified water pump decanter. By maintaining a safety zone between clarified water and activated sludge zones the drawing off of sludge is reliably prevented.
With the wastewater treatment plants, which are designed for the treatment target with denitrification (XLAM variants), the SBR tank is additionally fitted with an agitator, which enables and intensive mixing of the tank contents, without addition of oxygen, for the formation of an anoxic environment for the denitrification. The agitator is secured to the edge of the tank. It can be lifted via the installed guide system with the aid of a davit and again be brought into the operating position.
The control of the individual process-technical processes of the complete wastewater treatment plant takes place via a central control box. Supported by the filling level dependent process steps all phases of the treatment process proceed in accordance with the specified program in the central control unit. If a fault occurs in one of the units the fault is automatically indicated. Depending on the priority of the fault the operation of the wastewater treatment plant is continued under emergency operation or the plant is taken out of service until the fault is remedied. This procedure serves to prevent malfunctions which could possibly cause damage to the units or, in the worst case, which could have an accidental discharge of untreated wastewater as a result.