Screw press and how to operate the screw press

摘要

To provide a screw press capable of improving efficiency separating a liquid from a liquid-containing material and discharging a plug cake from a filtration cylinder without moving a screw to the filtration cylinder.SOLUTION: In a screw press provided with a filtration cylinder 1 charged with a liquid-containing material, a first screw 3 and a second screw 4 concentrically arranged with the filtration cylinder 1, a first rotating mechanism 7 rotating the first screw 3 and a second rotating mechanism 20 rotating the second screw 4 independently from the first screw 3,: the second screw 4 is arranged at the downstream side of the first screw 3 in a transfer direction D of the liquid-containing material; the second rotating mechanism 20 can rotate the second screw 4 at a rotational speed different from the first screw 3; the rotation direction of the second screw 4 can be switched to the same direction or a reverse direction to the rotation direction of the first screw 3; and the winding number of a second screw blade 4B is less than 3.SELECTED DRAWING: Figure 1