The decanter operation and speed is controlled through use of a variable frequency drive (VFD). As a result, the decanter discharge rate is constant from the time the decanter enters the water to the time it reaches the BWL. Effluent volume per linear foot of weir is controlled and constant versus gravity style decant systems.
At “park” position, the decanter provides “fail safe” overflow protection in the event of a power failure. Settled supernatant flow raise the scum gate floats allowing water to flow under the scum baffle and over the decanter weir free of floatable scum under power failure or storm mode.
The decanter weir always is visible from the basin walkway. This feature provides the operator with a continuous visual check of the effluent quality.
The Wagner Fluid System decants from the top and moves downward withdrawing only clear water from the basin and preventing disruption of the settling solids. All maintenance can be performed from the safety platform without entering the basin.