AU2017202629B1

AU2017202629B1 - A centrifuge basket

Info

Publication number: AU2017202629B1
Application number: AU2017202629A
Authority: AU
Inventors: Yusuf CAJEE; Steven Paul Coleman
Original assignee: Aqseptence Group Pty Ltd
Current assignee: Aqseptence Group Pty Ltd
Priority date: 2017-04-20
Filing date: 2017-04-20
Publication date: 2018-07-05
Anticipated expiration: 2037-04-20

Abstract

A centrifuge basket 10 includes a support structure 12 defining a pair of opposed ends 14, 16, an opening 18 being arranged at a first end 14 of the support structure12. A screening arrangement 20 line the structure 12, the screening arrangement 20 defining a plurality of spaced, parallel screening slots 22 extending between the ends of the support structure 14, 16, each slot 22 being arranged at an acute angle relative to an edge 24 of the screening arrangement 20 which forms a perimeter of the opening 18 at the first end 14 of the support structure 12.

Description

"A centrifuge basket"

Technical Field [0001] This disclosure relates, generally, to separation equipment and, more particularly, to a centrifuge basket for separation equipment.

Background [0002] Centrifuge-type screening is used to separate liquid phase material from solids to reduce the moisture content of such solids. Such a process is commonly referred to as dewatering. Efficiently dewatering ores and minerals improves the recovery of those ores and minerals.

[0003] However, such materials are extremely abrasive and can, as a result, reduce the life of separation equipment used to effect the screening.

Summary [0004] In some aspects of the disclosure, there is provided a centrifuge basket which includes a support structure defining a pair of opposed ends, an opening being arranged at a first end of the support structure; a screening arrangement lining the structure and defining a screening surface in an interior of the basket, the screening arrangement comprising a plurality of screening elements, adjacent screening elements defining a screening slot between them to provide a plurality of spaced, parallel screening slots extending between the ends of the support structure, and each slot being arranged at an acute angle relative to an edge of the screening arrangement which forms a perimeter of the opening at the first end of the support structure; and a plurality of agitator bars arranged on the screening surface of the screening arrangement.

[0005] It will be appreciated that, when reference is made to the screening slots extending between the ends of the support structure, that terminology is intended to encompass applications where the screening slots extend between, but terminate short of, one or both ends of the support structure.

[0006] The support structure may comprise a framework. The framework may be in the form of a frustum, the first end of the support structure forming a base of the frustum with a second end of the frustum also being open. In use, the second end may be closed off by a mounting plate against which are material to be separated impinges.

[0007] The screening arrangement may be made up of a plurality of discrete panels, each panel defining the screening slots. Each panel may have a longer, first edge and an opposed parallel, shorter, second edge with sides tapering towards the second edge, an included angle between each screening slot and one of the sides being greater than about 20°. The included angle may lie in a range between about 25° to 75°. In some embodiments, the included angle lies in a range between about 30° to 60°. In an embodiment, the included angle may be about 30°. However, in other embodiments, the included angle may range from about 25° to 30°, 30° to 35°, 35° to 40°, 40° to 45°, 45° to 60°, 60° to 65°, 65° to 70°, or 70° to 75°.

[0008] The screening slots may extend uninterruptedly between the ends of the support structure. Each screening element may be in the form of a profiled wire.

[0009] In an aspect of the disclosure, there is provided a screening panel for a centrifuge basket, the screening panel including: a body having a pair of opposed edges, a first edge being longer than a second edge and a pair of sides tapering towards the second edge, the body comprising a plurality of screening elements defining a screening surface and adjacent screening elements defining a screening slot between them to provide a plurality of spaced, parallel screening slots with an included angle between each screening slot and one of the sides being an acute angle greater than about 20°; and a plurality of agitator bars arranged on the screening surface of the body.

[0010] The disclosure extends also to separation equipment which includes a centrifuge basket as described above.

Brief Description of Drawings [0011] An embodiment of the disclosure is now described by way of example with reference to the accompanying drawings in which: - [0012] Fig. 1 shows a perspective view of an embodiment of a centrifuge basket; [0013] Fig. 2 shows a side view of the centrifuge basket; [0014] Fig. 3 shows a sectional side view of the centrifuge basket taken along line III-III in Fig. i; [0015] Fig. 4 shows a front view of a screening panel used in the centrifuge basket; and [0016] Fig. 5 shows, on an enlarged scale, part of the screening surface of the screening panel of Fig. 4.

Detailed Description of Exemplary Embodiments [0017] In the drawings, reference numeral 10 generally designates an embodiment of a centrifuge basket. The centrifuge basket 10 includes a support structure 12 defining a pair of opposed ends 14 and 16. The end 14 defines a materials inlet opening 18 (Fig. 1). The opposed end 16 of the support structure 12 is also open but, in use, is secured to a backing plate (not shown) against which material can impinge.

[0018] A screening arrangement 20 lines an interior surface of the support structure 12. The screening arrangement 20 defines a plurality of spaced, parallel screening slots 22. The slots 22 extend between the ends 14 and 16 of the support structure 12. Each slot 22 is arranged at an acute angle relative to an edge 24 of the screening arrangement 20, the edge 24 forming a perimeter of the opening 18 at the end 14 of the support structure 12.

[0019] In an embodiment, the support structure 12 is in the form of a framework 26 of a wear-resistant material such as a suitable steel material. The framework 26 of the support structure 12 comprises a pair of opposed annular elements, or rings 28 and 30 defining the ends 14 and 16, respectively. The ring 28 is of a larger diameter than the ring 30 so that the framework 26 of the support structure 12 adopts the shape of a frustum with the ring 28 forming a “base” of the frustum.

[0020] The ring 30 mounts a collar 32 to which a plurality of strengthening elements, in the form of strengthening bars, 34 are connected, the bars 34 extending to, and supporting, the ring 28.

[0021] A plurality of agitator bars 36 and 38 (Fig. 3) are arranged operatively inwardly of a screening surface of the screening arrangement 20. The agitator bars 36 extend between the rings 28 and 30, i.e. the full length of the basket 10. The bars 38 are mounted to the ring 30 and extend a short distance from the ring 30. The agitator bars 36 and 38 serve to agitate material received in the interior of the basket 10 to inhibit caking of the material on the inner surface of the screening arrangement 20 and to improve moisture extraction from the material. It is to be noted that the bars 38 are omitted from Fig. 1 for the sake of clarity.

[0022] The screening arrangement 20 comprises a plurality of discrete panels 40 (Fig. 4). Typically, four such panels 40 are provided to make up the screening arrangement 20. Each panel 40 is fabricated from a sheet of Vee-Wire® screen 48 (Vee-Wire is a registered trade mark of Johnson Screens, Inc, 2000 St James Place, Houston, TX, 77056, USA). The sheet is formed into the shape shown in Fig. 4 having a pair of parallel edges 24 and 42 which are arcuate and rectilinear side edges 44, 46 which taper towards each other from the edge 24 to the edge 42.

[0023] The Vee-Wire® screen 48 is made up of a plurality of profiled screening elements of a suitable metal, such as stainless steel. More particularly, each screening element is in the form of a substantially V-shaped screening bar 50. Adjacent screening bars 50 define one of the slots 22 between them. The screening bars 50 are supported on support bars 51 (Figs. 1 and 2).

[0024] With the arrangement of panel 40, as described above, an included angle, A, between each slot 22 and the side 44 of the panel 40 is an acute angle of greater than about 20° but less than about 75°. In an embodiment, the included angle, A, is about 30°. As a result, the slots 22 extend at an angle from the opening 18 to the opening 16, rather than being orthogonally arranged relative to those openings.

[0025] This results in slots 22 of increased length which, consequently, leads to an improved utilisation of the open area of the screening arrangement 20 resulting in improved moisture extraction from the material injected into the interior of the centrifuge basket 10 in the direction of arrow 52 (Fig. 2), in use.

[0026] In use, the centrifuge basket 10 is mounted to rotate about a substantially horizontal rotational axis 54 (Fig. 2). Material to be screened is inserted into the centrifuge basket 10, in the direction of the arrow 52, via the opening 18 to impinge on the screening arrangement 20. Rotation of the centrifuge basket 10 results in moisture being extracted from the material and expelled through the screening slots 22. Remaining material, having a lower moisture content, is discharged from the centrifuge basket 10 at an operatively bottom edge, or lip, 56 (Fig. 2) of the opening 18 for further processing.

[0027] Continued rotation of the centrifuge basket 10 about the rotational axis 54 causes the material to impact against the agitation bars 36 and 38 which inhibits caking of the material on the screening surface of the screening arrangement 22, results in continued agitation of the material and allows additional moisture to be extracted from the material and expelled through the slots 22 of the screening arrangement 20.

[0028] It is an advantage of the described embodiment that, as described above, longer screening slots 22 which provides an improved utilisation of the open area of the screening arrangement 20 of the centrifuge basket 10. In addition, because the slots 22 are arranged at an angle relative to the inflow of material, the material does not impact at right angles to leading edges 58 (Fig. 5 of the screening bars 50 of the screening arrangement 20. This results in reduced impact damage to the screening bars 50 improving the working life of the screening arrangement 20 and, hence, the centrifuge basket 10. It will be appreciated that impacts of sufficiently high force on the screening bars 50 could result in the bars being damaged causing an increase in the width of the screening slots 22. Material which otherwise would be available for processing could thus be lost through those slots of increased width.

[0029] It will be appreciated by persons skilled in the art that numerous variations and/or modifications may be made to the above-described embodiments, without departing from the broad general scope of the present disclosure. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive.

Claims

CLAIMS:

1. A centrifuge basket which includes a support structure defining a pair of opposed ends, an opening being arranged at a first end of the support structure; a screening arrangement lining the structure and defining a screening surface in an interior of the basket, the screening arrangement comprising a plurality of screening elements, adjacent screening elements defining a screening slot between them to provide a plurality of spaced, parallel screening slots extending between the ends of the support structure, and each slot being arranged at an acute angle relative to an edge of the screening arrangement which forms a perimeter of the opening at the first end of the support structure; and a plurality of agitator bars arranged on the screening surface of the screening arrangement.
2. The centrifuge basket of claim 1 in which the support structure comprises a framework.
3. The centrifuge basket of claim 2 in which the framework is in the form of a frustum, the first end of the support structure forming a base of the frustum with a second end of the frustum also being open.
4. The centrifuge basket of any one of the preceding claims in which the screening arrangement is made up of a plurality of discrete panels, each panel defining the screening slots.
5. The centrifuge basket of claim 4 in which each panel has a longer, first edge and an opposed parallel, shorter, second edge with sides tapering towards the second edge, an included angle between each screening slot and one of the sides being greater than about 20°.
6. The centrifuge basket of claim 5 in which the included angle lies in a range between about 25° to 75°.
7. The centrifuge basket of claim 5 or claim 6 in which the included angle lies in a range between about 30° to 60°.
8. The centrifuge basket of any one of claims 5 to 7 in which the included angle is about 30°.
9. The centrifuge basket of any one of the preceding claims in which the screening slots extend uninterruptedly between the ends of the support structure.
10. The centrifuge basket of any one of the preceding claims in which each screening element is in the form of a profiled wire.
11. A screening panel for a centrifuge basket, the screening panel including: a body having a pair of opposed edges, a first edge being longer than a second edge and a pair of sides tapering towards the second edge, the body comprising a plurality of screening elements defining a screening surface and adjacent screening elements defining a screening slot between them to provide a plurality of spaced, parallel screening slots with an included angle between each screening slot and one of the sides being an acute angle greater than about 20°; and a plurality of agitator bars arranged on the screening surface of the body.
12. Separation equipment which includes a centrifuge basket as claimed in any one of claims 1 to 10.