The belt filter press comprises an optional pre-dewatering drum and a set of two filter belts that are driven and compressed by a series of rollers. When so required, the sludge is thickened to an ideal consistency by the pre-dewatering drum before feeding it to the filter cloth belts where it is squeezed between the two filter cloth belts by means of a number of compression rollers. In some cases the sludge needs to be pre-treated with a polymer to increase the dewatering properties and to reduce the tendency of the sludge to stick to the filter cloth. The filter cloth belts are automatically cleaned by means of spray nozzles and the dewatered sludge is discharged in the form of a relatively dry ‘cake”.


  • Dewatering of screened solids or sludge
  • Receives sludge from clarifier underflow or DAF overflow
  • Polymer mixer flocculates the sludge
  • Pre-dewatering drum thickens the sludge for inlet consistency below 6%
  • Sludge is pressed between two rotating filter belts
  • Compaction by pressing rollers
  • Dryness controlled by adjustable roller pressure and belt speed

Technical specifications:

Base frame carbon steel epoxy coated
Rollers   carbon steel or stainless steel
Roller coating  Rilsan rubber
Pressing rollers 5, 7, 9 or 11
Belt  polyurethane clipper seam or seamless
Belt aperture  0.25mm standard
Belt widths    800 – 3000mm
Belt speed   1 – 5 m/min
Dry solids flow rate   180 – 360 kg/h/meter belt-width
Solids dryness up to 65%