Screw Presses for Sludge Dewatering

Screw presses are used to dewater sludge solids suspensions from an inlet consistency of 3 to 12% to an outlet consistency of 30% and higher. The operation of a screw press is relatively straightforward. A tapered rotating screw moves the sludge through the press as the pressure gradually increases. Filtrate is forced out through perforations in the casing while the solids are compressed. A cone or door at the discharge end maintains the discharge consistency in the desired range. This course covers the design and operation of screw presses used for sludge dewatering, common issues, and maintenance and troubleshooting best practices.