Abstract: Screw press for separation of liquid from solid liquid mixtures, especially pulp suspensions, with a casing with perforations for liquid and a screw shaft provided in it between which a circular gap is formed through which the solid liquid mixture is pressed. Furthermore, a counter pressure device in the area of the discharge end of the circular gap is provided. To reduce the space requirement in the discharge area at the discharge end of the circular gap, which makes it possible to reduce the size of the discharge casing and cut costs due to a less complicated design, the counter pressure device has a counter pressure surface, the radius of which is decreasing in the conveying direction of the solid liquid mixture.

Abstract: A process and apparatus for removing water from a mechanical pulp, chemical pulp or paper sheet, carried between top and bottom wires running through a dewatering machine having a first dewatering zone. The apparatus includes at least one suction box positioned downstream of the first dewatering zone. The process includes generating an air current in at least one of the wires downstream of the first dewatering zone with the suction box. The air current removes water from the wire and directs it into an inner chamber of the suction box. The invention also refers to a device for implementing the process.

Abstract: Screw press for separation of liquid from solid liquid mixtures, especially pulp suspensions, with a casing with perforations for liquid and a screw shaft provided in it between which a circular gap is formed through which the solid liquid mixture is pressed. Furthermore, a counter pressure device in the area of the discharge end of the circular gap is provided. To reduce the space requirement in the discharge area at the discharge end of the circular gap, which makes it possible to reduce the size of the discharge casing and cut costs due to a less complicated design, the counter pressure device has a counter pressure surface, the radius of which is decreasing in the conveying direction of the solid liquid mixture.

Abstract: A process and apparatus for removing water from a mechanical pulp, chemical pulp or paper sheet, carried between top and bottom wires running through a dewatering machine having a first dewatering zone. The apparatus includes at least one suction box positioned downstream of the first dewatering zone. The process includes generating an air current in at least one of the wires downstream of the first dewatering zone with the suction box. The air current removes water from the wire and directs it into an inner chamber of the suction box. The invention also refers to a device for implementing the process.