摘要 |
A screw press (1) for dehydrating slurry, comprising: a screen outer tube (5); a screw shaft (20); a slurry supplying portion (10); and a driving system (25) for rotatably driving the screen outer tube (5) and the screw shaft (20). The driving system (25) is adapted to rotate the screw shaft (20) in one direction, and simultaneously, rotate the screen outer tube (5) in a direction opposite to the rotating direction of the screw shaft. The driving system (25) has a transmission (26, 46) for changing the number of revolutions of at least one of the screen outer tube and the screw shaft. The screen outer tube (5) is rotated in a direction opposite to that of the screw shaft (20) at the number of revolutions within a predetermined range, so that high dehydrating effect can be obtained. |