The secondary clarification of a conventional treatment plant often is hydraulically overloaded, resulting in an insufficient effluent quality, especially with regard to suspended solids and the parameters COD, N und P.

A state-of-the-art solution is achieved by using a Hybrid System to draw a side stream directly from the conventional aeration tank into a membrane filtration. The flow rate corresponds to the overload of the secondary clarifier, so that the reduced surface charge allows for a proper sedimentation.

As with the parallel Hybrid System, the Combined System also offers a cost-efficient solution with very low footprint requirements. The high-quality effluent can either be re-used or blended with the secondary effluent in order to improve the discharge parameters of the complete plant.