Assembly for the separation of gas from a fiber suspension has a main and a secondary dividing wall in the container with underpressure to recirculate the suspension and direct gas-free suspension into a dwell zone

摘要

The appts. (1) for the removal of gas from a fiber suspension (2) has a longitudinal container (3), with an underpressure, for the suspension to flow (S) through, with a main dividing wall (16) forming an upper overflow edge (17) forming an overflow (15), and a secondary dividing wall (24) with an upper edge (25) for the gas-free suspension (2) to the outlet (21). The back-up height (HSH) of the main dividing wall (16) is higher than the back-up height (NSH) of the secondary dividing wall (24). The outlet (21) for the gas-free suspension (2) is followed by a hydraulic stabilizer (28). The hydraulic stabilizer (28) for the gas-free suspension (2) is a dwell vessel to give a set dwell time and dwell vol., with an inner contour structured for the optimum suspension flow characteristics. The inner contour is pref. a longitudinal and prone cylinder, or a conical tube (29) aligned on the suspension flow direction (S). The horizontal cylinder, as a hydraulic stabilizer, has an inlet for the fiber suspension (2) from the overflow formed by the secondary dividing wall (24) into the outlet (21), defined by a leading (22) and a trailing (23) edge. The secondary dividing wall (24) is at the same level as the leading edge (22) of the outlet (21) for the gas-free suspension. The hydraulic stabilizer is directly or indirectly after the outlet (21) from the gas removal stage, with a tube or hose link. The suspension dwell time in the stabilizer is 2-60 secs. and pref. 5-20 secs. The vol. of gas-free suspension dwelling in the stabilizer is 0.8-100.0 m3 and pref. 4-70 m3. The overflow from the main dividing wall (16) passes through an outlet (16) for recirculation, where the wall is at the same level as the leading edge (19) of the outlet and at the same level as the trailing edge (23) of the outlet (21) for gas-free suspension. The upper edges (17,25) of the main (16) and/or secondary (24) dividing walls are aligned against the direction (S) of the suspension (2) flow, using divided walls where their upper sections can be pitched at the required angles. The main (16) and/or secondary (24) dividing walls, on a vertical plane in relation to the suspension level (6), are in parallel with a curvature or an angle, and the edges (22,23) of the outlet (21) for gas-free suspension are rounded (26) or chamfered. The underpressure is generated within the container (3) by an underpressure connection (9), an underpressure channel (10) and at least one underpressure pump (11) and channel (12). A number of jets (13) moisten the inner surfaces (14) of the container (3) where the fiber suspension (2) is not in contact.