SCREW PRESS

The invention relates to a vertical screw press (1) for separating solids, e.g. fibres, from a suspension, e.g. a pulp suspension, having a cylindrical screening basket (9, 10, 11), and a press screw mounted rotatably in the screening basket (9, 10, 11) via a drive (2) and having a central screw shaft (12) and a, preferably double-flight, screw helix (13) arranged thereon and extending at least along a majority of the screw shaft (12), wherein an inlet (8) for the suspension, an outlet (6) for filtrate and a discharge (7) for the dewatered solids are provided. It is primarily characterized in that the cylindrical screening basket (9, 10, 11) is surrounded by a filtrate backlog container (3, 4, 5), consists of a plurality of parts as seen in the axial direction, and at least one part, preferably the bottommost part (5), has a filtrate backlog container having a larger diameter, wherein the rotatable screw shaft (12) can be embodied in a reversible manner, wherein the inlet (8) for the suspension is provided at the top end and the discharge (7) for the dewatered solids is provided at the bottom end, with the result that the feed direction of the screw press (1) extends from top to bottom and wherein an outlet (6) for filtrate is provided at the bottom end of the filtrate backlog container (5). This enables both efficient dewatering and ready accessibility for cleaning and maintenance without taking apart the entire machine.