Outlet device of a solid-bowl screw centrifuge with a diverting channel

Abstract

The invention relates to an outlet device (10) of a solid-bowl screw centrifuge for separating a multi-phase material, which outlet device is arranged on an end wall (12) of a centrifuge drum, which rotates about a longitudinal axis, at an outlet opening (20) formed in the end wall, which outlet device comprises a diverting channel (22) for diverting a liquid phase of the material which passes through the outlet opening (20), wherein the diversion relative to the longitudinal axis amounts to an angle (32) between 50° and 90° with respect to the circumferential direction, and which outlet device has an aligned rectilinear weir edge (30) for limiting the emergence of the liquid phase, wherein the angle of the alignment of the weir edge (30) relative to the end wall (12) as viewed from the outlet opening (20) amounts to between 0° relative to the end wall and minus 6° toward the end wall.

Claims

1. An outlet device (10) of a solid-bowl screw centrifuge for separating a multi-phase material, which outlet device is arranged on an end wall (12) of a centrifuge drum, which rotates about a longitudinal axis (14), at an outlet opening (20) formed in the end wall (12), which outlet device comprises a diverting channel (22) for diverting a liquid phase of the material which passes through the outlet opening (20), wherein the diversion relative to the longitudinal axis (14) amounts to an angle between 50° and 90° with respect to the circumferential direction, and which has an aligned rectilinear weir edge (30) for limiting the emergence of the liquid phase, wherein the angle of the alignment of the weir edge (30) relative to the end wall (12) as viewed from the outlet opening (20) is less than 0° to minus 6° toward the end wall (12), wherein the weir edge (30) is at the end of the diverting channel (22).

2. The outlet device according to claim 1, wherein the diverting channel (22) is designed as a radially inward open channel.

3. The outlet device according to claim 1, wherein the diverting channel (22) is designed to be narrowing in the flow direction of the liquid phase.

4. The outlet device according to claim 1, wherein at least one flow guiding element (36) is arranged in the diverting channel (22).

5. The outlet device according to claim 1, wherein in the flow direction of the liquid phase behind the weir edge (30), a flow guiding surface (38), over which exiting liquid phase flows, is provided, and which, as viewed in the axial direction (46) is designed without a side wall at least in sections on one side.

6. The outlet device according to claim 5, wherein the flow guiding surface (38) has a main flow direction which is oriented to be pivoted above the weir edge (30) toward the end wall (12) as compared to a main flow direction of the liquid phase.

7. The outlet device according to claim 5, wherein the flow guiding surface (38) is spaced from the end wall (12) on the side of the drum.

8. The outlet device according to claim 1, wherein the diverting channel (22) is mounted to the end wall (12) of the centrifuge drum so as to be adjustable.

9. A solid-bowl screw centrifuge for separating a multi-phase material by means of a centrifuge drum which has at least one outlet device (10) according to claim 1.

10. An outlet device (10) of a solid-bowl screw centrifuge for separating a multi-phase material, which outlet device is arranged on an end wall (12) of a centrifuge drum, which rotates about a longitudinal axis (14), at an outlet opening (20) formed in the end wall (12), which outlet device comprises a diverting channel (22) for diverting a liquid phase of the material which passes through the outlet opening (20), wherein the diversion relative to the longitudinal axis (14) amounts to an angle between 50° and 90° with respect to the circumferential direction, and which has an aligned rectilinear weir edge (30) for limiting the emergence of the liquid phase, wherein the angle of the alignment of the weir edge (30) relative to the end wall (12) as viewed from the outlet opening (20) amounts to between 0° relative to the end wall (12) and minus 6° toward the end wall (12), wherein in the flow direction of the liquid phase behind the weir edge (30), a flow guiding surface (38), over which exiting liquid phase flows, is provided, and which, as viewed in the axial direction (46) is designed without a side wall at least in sections on one side.

11. An outlet device (10) of a solid-bowl screw centrifuge for separating a multi-phase material, which outlet device is arranged on an end wall (12) of a centrifuge drum, which rotates about a longitudinal axis (14), at an outlet opening (20) formed in the end wall (12), which outlet device comprises a diverting channel (22) for diverting a liquid phase of the material which passes through the outlet opening (20), wherein the diversion relative to the longitudinal axis (14) amounts to an angle between 50° and 90° with respect to the circumferential direction, and which has an aligned rectilinear weir edge (30) for limiting the emergence of the liquid phase, wherein the angle of the alignment of the weir edge (30) relative to the end wall (12) as viewed from the outlet opening (20) amounts to between 0° relative to the end wall (12) and minus 6° toward the end wall (12), wherein in the flow direction of the liquid phase behind the weir edge (30), a flow guiding surface (38), over which exiting liquid phase flows, is provided, wherein the flow guiding surface (38) has a main flow direction which is oriented to be pivoted above the weir edge (30) toward the end wall (12) as compared to a main flow direction of the liquid phase.

12. An outlet device (10) of a solid-bowl screw centrifuge for separating a multi-phase material, which outlet device is arranged on an end wall (12) of a centrifuge drum, which rotates about a longitudinal axis (14), at an outlet opening (20) formed in the end wall (12), which outlet device comprises a diverting channel (22) for diverting a liquid phase of the material which passes through the outlet opening (20), wherein the diversion relative to the longitudinal axis (14) amounts to an angle between 50° and 90° with respect to the circumferential direction, and which has an aligned rectilinear weir edge (30) for limiting the emergence of the liquid phase, wherein the angle of the alignment of the weir edge (30) relative to the end wall (12) as viewed from the outlet opening (20) amounts to between 0° relative to the end wall (12) and minus 6° toward the end wall (12), wherein in the flow direction of the liquid phase behind the weir edge (30), a flow guiding surface (38), over which exiting liquid phase flows, is provided, wherein the flow guiding surface (38) is spaced from the end wall (12) on the side of the drum.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Hereinafter, exemplary embodiments of the outlet device according to the invention on a solid-bowl screw centrifuge will be explained in more detail with reference to the attached schematic drawings. Shown is in:

(2) FIG. 1 a frontal view of an end wall of a centrifuge drum of a solid-bowl screw centrifuge, with an outlet device according to the invention being arranged on the end wall,

(3) FIG. 2 a section II-II of the end wall according to FIG. 1,

(4) FIG. 3 a first variant of the embodiment according to FIG. 2,

(5) FIG. 4 a second variant of the embodiment according to FIG. 2,

(6) FIG. 5, FIG. 5a the view V of the outlet device according to FIG. 1,

(7) FIG. 6 a first variant of the embodiment according to FIG. 5,

(8) FIG. 7 a second variant of the embodiment according to FIG. 5,

(9) FIG. 8 a third variant of the embodiment according to FIG. 5,

(10) FIG. 9 a fourth variant of the embodiment according to FIG. 5,

(11) FIG. 10 a fifth variant of the embodiment according to FIG. 5,

(12) FIG. 11 a sixth variant of the embodiment according to FIG. 5, and

(13) FIG. 12 a longitudinal section of the end wall according to FIG. 1 with the outlet device according to FIG. 11.

DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS

(14) In FIGS. 1 to 12, diverse outlet devices 10 are depicted, which are each arranged to be radially adjustable on an end wall 12 of a not further depicted centrifuge drum of a solid-bowl screw centrifuge of the conventional type of construction. The centrifuge drum may in this case rotate at high speed about a longitudinal axis 14 in a rotational direction 16. Inside the centrifuge drum, a material to be cleared is present, whose light liquid phase accumulates radially inside and occupies a pool radius or a liquid level 18. The liquid level 18 is determined by an outlet opening 20 positioned in the end wall 12 and through which the material of the light phase may flow out of the centrifuge drum to the outside.

(15) In FIGS. 2 to 4, three variants of the outlet opening 20 are illustrated, with the variant according to FIG. 2 being designed as a cylinder passage opening oriented in the longitudinal direction, the variant according to FIG. 3 being designed as an obliquely oriented cylinder passage opening, and the variant according to FIG. 4 being designed as a passage opening tapering in the form of a truncated cone.

(16) In the flow through direction behind the outlet opening 20 or outside in front of the outlet opening 20, the outlet device 10 is positioned with an associated diverting channel 22. The exiting light phase flows through the outlet opening 20 into this diverting channel 22 and is diverted on this occasion from the direction of the longitudinal axis 14 transversely to the longitudinal axis 14 into the associated circumferential direction of the centrifuge drum. In this manner, the flow pulse of the liquid phase flowing out may be utilized to impart a pulse to the centrifuge drum acting in the rotational direction. This allows driving energy for driving the centrifuge drum to be recovered.

(17) The diverting channel 22 is designed as a radially inward open channel with a first side wall 24, a bottom surface 26 and a second side wall 28. In this case, the side walls 24 and 28 are oriented such that this channel continuously tapers in the flow direction of the exiting light phase. At the end of the gutter-like channel, an associated weir edge 30 of the outlet device 10 is positioned. This weir edge 30 forms the part of the bottom surface 26 projecting furthest radially inward, and this defines the liquid level 18.

(18) The diversion of the outflowing material of the liquid phase by means of the diverting channel 22 relative to the outside of the end wall 12 has an angle 32 of between 50° and 90° from the direction of the longitudinal axis 14 toward the circumferential direction or rotational direction 16 of the centrifuge drum.

(19) The weir edge 30 at the end of the diverting channel 22 is in this case designed to be rectilinear and extends at an angle 34 of between minus 6° toward the end wall 12 and 0° away from the end wall 12. In other words, the weir edge 30 extends at an angle 34 of between 0° relative to the end wall 12 and minus 6° toward the end wall 12.

(20) A rib-shaped flow guiding element 36 is positioned in the diverting channel 22 according to FIG. 6 in the center of the bottom surface 26 thereof. This flow guiding element 36 projects radially inward from the bottom surface 26 as a narrow wall. The flow guiding element 36 extends from the beginning to the end of the diverting channel 22.

(21) In FIG. 7, one embodiment of the outlet device 10 is depicted, wherein a flow guiding surface 38 is formed at the end of the channel of the diverting channel 22. To this end, the side wall 28 of the diverting channel 22 pointing toward the end wall 12 is shortened, and the weir edge 30 is designed to have a second weir edge portion 40 pointing toward the end wall 12. As viewed in the top view, the weir edge 30 thus forms a tip pointing in the flow direction of the material flowing off (see FIG. 7 at the bottom).

(22) FIG. 8 shows an outlet device 10, in which the side walls 24 and 28 are designed like in the example shown in FIG. 6. At the same time, a flow guiding surface 38 is positioned in the flow direction behind the weir edge 30. This flow guiding surface 38 is designed as a mostly planar surface without side edges or side walls and so as to expand in a funnel-shape in the flow direction.

(23) FIG. 9 depicts one exemplary embodiment of an outlet device 10, in which such a flow guiding surface 38 as shown in FIG. 8 is provided in addition, on its side facing away from the end wall 12, with an end wall 42. The side wall 42 extends in this case only over the rear part of the flow guiding surface 38 in the flow direction, whereas an area or portion 44 of the projection of the weir edge 30 in the axial direction 46 is designed without a side wall. This free area on the flow guiding surface allows as little air resistance as possible to develop there during the rotation of the centrifuge drum because of the minimum projection surface.

(24) In FIGS. 10 and 11, two further embodiments of an outlet device 10 are depicted, in which the flow guiding surface 38 is provided with a second side wall 48 also on its side facing the end wall 12. In this case, the side walls 42 and 48 according to FIG. 10 are designed such as to form a channel tapering in the flow direction, whereas the side walls 42 and 48 according to FIG. 11 extend in parallel to one another.

(25) FIG. 12 finally depicts that the respective flow guiding surfaces 38 are always radially slightly further outside directly behind the associated weir edges 30 so that a small step 50 is developed directly behind the weir edge 30.

(26) Finally, it should be noted that all of the features mentioned in the application documents and in particular in the dependent claims should be provided, even individually or in any combination, with individual protection, despite of the formal back reference made to one or more particular claims.

LIST OF REFERENCE NUMERALS

(27) 10 outlet device 12 end wall of a centrifuge drum of a solid-bowl screw centrifuge 14 longitudinal axis 16 rotational direction 18 pool radius or liquid level 20 outlet opening 22 diverting channel 24 side wall of the diverting channel 26 bottom surface of the diverting channel 28 side wall of the diverting channel 30 weir edge 32 angle of the diversion of the flow of the liquid phase 34 angle of the orientation of the weir edge 36 flow guiding element 38 flow guiding surface 40 second weir edge portion 42 side wall of the flow guiding surface 44 portion without side wall 46 axial direction 48 side wall of the flow guiding surface 50 step