HUBER Screw Press Q-PRESS®

Cost-effective sludge dewatering for independence in sludge disposal

The Q-PRESS® is a screw press with a conical screw shaft and cylindrical sieves consisting of three treatment zones: inlet and drive zone, three-part thickening and dewatering zone, and press zone with pneumatic counter-pressure cone.

In the first part of the thickening and dewatering zone the supernatant is quickly removed by the feed pump via a large free filter surface at a low primary pressure. A pressure probe in the feed area controls the primary pressure thus ensuring a constantly high filtrate quality.

In the second part of the screen the volume of material between the screw flights is reduced by the conical screw and the sludge pressed against the inner screen surface so that the sludge is dewatered, with a continuous reduction of the filter cake thickness. The screen apertures are much smaller in this screen section.

In the third part of the screen the residual water is pressed out of the sludge, at a minimum filter cake thickness, by the pneumatic counter-pressure cone at the press discharge. The dewatered sludge is pushed by the conveying screw past the pressure cone into the discharge chamber. The sludge residence time in the screw press and thus the filtration time can be adjusted to individual requirements by adjusting the rotational speed of the screw shaft.

Dewatering of thin sludges

Due to pump feeding, large volumes of sludge water are removed already in the pre-dewatering zone. This permits cost-efficient dewatering of thin sludges with a solids concentration < 1%. This application allows typical dewatering results of 18 – 25% DS and achieves a sludge volume reduction up to > 97% in a single step!

Variable sludge characteristics

Dewatering performance is usually impaired and operator attention increased by frequently varying sludge quality. Our HUBER Screw Press Q-PRESS® automatically self-adjusts to over- and under-loading.


  • Insensitive to coarse material due to the wide gap between the screw conveyor and sieve
  • No permanent sieve cleaning required, low wash water consumption
  • Pneumatically controlled pressure cone system
  • Defined sludge residence time
  • Permanent movement of filter cake, minimized filter resistances
  • Minimum wear due to the low speed of the compacting screw
  • Minimized noise
  • Low energy consumption
  • High dewatering degrees with fibrous sludge