Step Screen is designed for in-channel installation and is used for fine screening of waste water. They consist of two sets of lamellas - a moving and a fixed one - which are separated by 2 to 6 mm spacing. The special arrangement of the lamellas forms filtering steps.
Waste water is screened while the lamella steps withhold the screenings. Throughout the operation the moving lamellas lift the screenings step by step until they are dropped off on the fixed lamellas. The inorganic particles in the waste water flow are withheld by the screen forming a “screenings mat”. In this way, the water level upstream rises making the filter surface wider while the “screenings mat” on the screen keeps increasingly finer particles.
As soon as the upstream water level reaches a set height, the screen starts its cycle rising up a step. During the cycle, the mobile lamellas lift screenings onto the next step until they reach the outlet for discharge.
