| 摘要 |
The device comprises a slowly rotating screening drum (1) which is provided with feeding devices for feeding waste water into the screening drum from one end (2) thereof and with devices for discharging solid substances out from the other end of the screening drum. The water is thereby filtered through a mantle (5) of the screening drum. The solid substances for their part are passed forwards inside the screening drum by means of transversal ribs (4) positioned slantingly with respect to the direction of rotation of the drum and, further, are agitated in the screening drum by the action of longitudinal ribs (3) extending over the length of the drum. In order to provide a filtration as effective as possible, at least some of the longitudinal ribs (3) are slanted with respect to the radial direction of the screening drum (1) in such a manner that an angle between that surface of the longitudinal rib (3) which faces in the direction of rotation of the screening drum and the inner surface of the screening drum mantle (5) is smaller than an angle between that surface of the longitudinal rib (3) which faces backwards with respect to the direction of rotation and the inner surface of the screening drum mantle (5). |
