The horizontal screw decanter centrifuge is mainly composed of a high-speed rotating drum, a spiral and a differential that rotates the same as the drum and rotates slightly higher or lower than the drum. When the suspension to be separated enters the centrifuge drum, the high-speed rotating drum generates a strong centrifugal force to settle the solid phase particles larger than the liquid phase density to the inner wall of the drum. Due to the different rotation speeds of the screw and the drum, the two exist. With relative motion (i.e., the difference in rotational speed), the solid phase deposited on the inner wall of the drum is pushed toward the outlet of the small end of the drum by the relative motion of the spiral and the drum, and the separated supernatant is discharged from the other end of the centrifuge. The role of the differential (gearbox) is to create a certain difference in rotational speed between the drum and the helix.
Centrifugal sedimentation is the addition of a mixture of solid and liquid to a cylindrical (or conical) rotor. Due to the centrifugal force, the solid settles in the liquid, and the settled material is further squeezed by centrifugal force to extrude the water to reach The purpose of separation of solids and liquids. There is a difference between the centrifugal settlement and the settlement under gravity: In gravity settlement, the acceleration of material settlement is equal to the acceleration of gravity, which is a constant value; in centrifugal settlement, the centrifugal force depends on the radius of gyration of the particle motion, and therefore, when the angular velocity is equal, The moving particles on different gyration radii are not subjected to the same centrifugal force.