Proceedings

With a large number of rural sewage treatment works spread over a wide area, sludge handling in the Anglian Water region incurs considerable costs. Sludge handling requires resources in terms of energy, maintenance, chemical demand and transport, and if new or more innovative ways to process sludge can be found, significant saving would be realised, which would contribute to the company’s sustainability targets.

The paper presents results of a trial conducted by Anglian Water’s Innovation Team investigating a type of low-energy dewatering technology – the Volute® dewatering screw-press. For dewatering conventional SAS only, the Volute produced a transportable cake of 20.8% DS, whilst adding primary (raw) sludge to produce a 90:10 SAS:raw mixture by mass, provided a cake of 22.5% DS, and 60:40 mix produced a cake of 34%DS.

Keywords: Volute, dewatering, screw press, municipal sludge, biosolids, innovation, energy, surplus activated sludge