Whilst the wastewater flows into the open front side of the screen and out through the screening elements on the left and right side (viewed in flow direction), solids are retained on the inner surface of the screening elements leading to gradual blinding of the surface, which has an impact on the level difference in the channel. Cleaning of the filter elements starts at a defined water level in the channel upstream of the screen. The filter elements start to circulate, thus transporting the screenings upwards and out of the channel.

In the upper part of the screen a spray nozzle bar sprays water onto the surface of the filter element from outside to remove the solids from the surface and flush them into an internal trough installed in the upper part of the screen from where the screenings are discharged by gravity. The screenings are usually treated further in a HUBER Wash Press WAP®.

CenterMax® pp - perforated plate screen

HUBER Band Screen CenterMax® with perforated plate, perforations from 1 to 10 mm.
High separation efficiency and retention of fibres and hair.

Typical applications for 1 and 2 mm perforation:
- Protection of hollow-fibre membrane filtration plants

Typical applications for 3 mm perforation:
- Protection of plate membrane filtration plants
 

CenterMax® Star - folded perforated plate screen

HUBER Band Screen CenterMax® with folded perforated plate, perforations 1 / 1.5 / 2 mm.
Increased screen surface for higher throughputs.
High separation efficiency and retention of fibres and hair.

Typical applications:
- Protection of membrane filtration plants

CenterMax® mesh - square mesh screen

HUBER Band Screen CenterMax® with mesh, mesh sizes from 0.2 up to 0.75 mm.
Maximum separation efficiency and reduction of COD and BOD by 20 – 40%.

Typical applications:
- Load reduction in the preliminary treatment stage
- Replacement for primary settlement tank
- River and sea outfall applications