Screw press having a plurality of throttle points and at least one cam movable transversely thereto

A process for pressing off fluids, from a fluid containing material comprising the steps of:

• a) providing a screw having a plurality of screw segments arranged consecutively in an axial direction of the press, each of the screw segments having an outer surface, each of said outer surfaces increasing in diameter for each consecutive screw segment in a transport direction;
• b) providing a fluid permeable mantel surrounding the screw and having an inner surface facing the screw outer surface defining a screw channel therebetween;
• c) flowing the fluid containing material into the screw channel;
• d) increasing the pressure of the fluid containing material at a plurality of throttle points disposed between adjacent screw segments by reducing the cross-sectional area of the screw channel at each of the throttle point;
• e) reducing the pressure of the fluid containing material following said increasing step at an expansion zone downstream from each of the throttle points;
• f) providing a transversely moveable cam disposed at one of said throttle points;
• and
• g) breaking up the fluid containing material at said at least one of the throttle points with the transversely movable cam.