Double pusher centrifuge

• US 20040206687A1
• Filed: 04/05/2004
• Published: 10/21/2004
• Est. Priority Date: 04/16/2003
• Status: Active Grant

• Current Assignee: Ferrum AG
• Original Assignee: Ferrum AG
• Inventors: Geiger, Roy, Reinach, Harald
• Granted Patent: US 7,025,211 B2
• Time in Patent Office: Days
• US Class Current: 210/360.1
• CPC Class Codes: B04B 11/06 Arrangement of distributors or collectors in centrifuges
• CPC Class Codes: B04B 3/02 discharging solid particles from the bowl by means coaxial with the bowl axis and moving to and fro, i.e. push-type centrifuges

Abstract

The invention relates to a double pusher centrifuge including a screen drum 3) rotatable about an axis of rotation (2) for separating a mixture (4) into a solid material cake (5) and a liquid phase (6), a mixture distributor (7) arranged in the screen drum (3) and having a pusher base device (8), which is arranged to be movable to and for along the axis of rotation (2), so that the solid material cake (5) is alternately displaceable with an outer ring zone (9). Furthermore, the double pusher centrifuge includes an infeed device (10) with which the mixture (4) can be introduced via the mixture distributor (7) into an empty space (11), which arises adjacent to the outer ring zone (9) on displacement of the solid material cake (5) by the pusher base device (8). In this arrangement the pusher base device (8) has acceleration surfaces (12) on both sides, which are inclined at a pre-determinable angle of inclination (γ) with reference to the radial direction, so that the mixture (4) introduced by the infeed device (10) can be accelerated to a pre-determinable peripheral speed before reaching the screen drum (3).

Claims

1. A double pusher centrifuge including a screen drum 3) rotatable about an axis of rotation (2) for separating a mixture (4) into a solid material cake (5) and a liquid phase (6), a mixture distributor (7) arranged in the screen drum (3) and having a pusher base device (8), which is arranged to be movable to and for along the axis of rotation (2), so that the solid material cake (5) is alternately displaceable with an outer ring zone (9), and with an infeed device (10) with which the mixture (4) can be introduced via the mixture distributor (7) into an empty space (11), which arises adjacent to the outer ring zone (9) on displacement of the solid material cake (5) by the pusher base device (8), characterised in that the pusher base device (8) has acceleration surfaces (12) on both sides, which are inclined at a pre-determinable angle of inclination (γ

) with reference to the radial direction, so that the mixture (4) introduced by the infeed device (10) can be accelerated to a pre-determinable peripheral speed before reaching the screen drum (3).

2. A double pusher centrifuge in accordance with claim 1, wherein the acceleration surface (12) is designed as a filter screen (121) for separating the liquid phase (6) from the mixture (4).

3. A double pusher centrifuge in accordance with claim 1 wherein the filter screen (121) is designed as a two-stage screen with a coarse filter (122) and a fine filter (123).

4. A double pusher centrifuge in accordance with claim 1, wherein the infeed device (10) includes an inlet funnel (101) for pre-acceleration of the mixture (4), which extends at a substantially constant opening angle (α

) conically diverging in the direction towards the pusher base device (8).

5. A double pusher centrifuge in accordance with claim 1, wherein the inlet funnel (101) has a curved shape and the opening angle (α

) of the inlet funnel (101) becomes larger in the direction towards the pusher base device.

6. A double pusher centrifuge in accordance with claim 1, wherein the inlet funnel (101) has a curved shape and the opening angle (α

) of the inlet funnel (101) becomes smaller in the direction towards the pusher base device.

7. A double pusher centrifuge in accordance with claim 1, wherein the inlet funnel (101) is rotatably arranged about a drive axis (131) and is rotatable about the drive axis (131) at a pre-determinable speed of rotation by means of a drive (13).

8. A double pusher centrifuge in accordance with claim 1, wherein the inlet funnel (101) is designed as a pre-filter screen (102) for the initial separation of the liquid phase (6) from the mixture (4).

9. A double pusher centrifuge in accordance with claim 1, wherein collecting means (14) are provided for collecting and draining the liquid phase (6) from the pre-filter screen (102).

10. A double pusher centrifuge in accordance with claim 1, in which the mixture distributor (7) includes a pre-acceleration funnel (71), which extends in the direction towards the infeed device (10) while conically diverging at an essentially constant pre-acceleration angle (β

).

11. A double pusher centrifuge in accordance with claim 1, wherein the pre-acceleration funnel (71) has a curved shape and the pre-acceleration angle (β

) of the pre-acceleration funnel (71) becomes larger in the direction towards the infeed device (10).

12. A double pusher centrifuge in accordance with claim 1, wherein the pre-acceleration funnel (71) has a curved shape and the pre-acceleration angle (β

) of the pre-acceleration funnel (71) becomes smaller in the direction towards the infeed device (10).

13. A double pusher centrifuge in accordance with claim 1, wherein the pre-acceleration funnel (71) is designed as a pre-acceleration screen (72) and collection devices (73) are provided at the mixture distributor (7)for draining the liquid phase (6).

14. A double pusher centrifuge in accordance with claim 1, wherein the pre-acceleration funnel (71) is so designed and arranged that the pre-acceleration funnel (71) is rotatable about an axis of rotation (151) by means of a rotary drive (15) at a pre-determinable speed of rotation.