AU5009901A

AU5009901A - Centrifuge with twin inlet

Info

Publication number: AU5009901A
Application number: AU50099/01A
Authority: AU
Inventors: Karl-Heinz Zettier
Original assignee: Westfalia Separator Food Tec GmbH
Current assignee: GEA Mechanical Equipment GmbH
Priority date: 2000-06-16
Filing date: 2001-06-01
Publication date: 2002-08-01
Anticipated expiration: 2021-06-01
Also published as: AU781953B2

Description

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION STANDARD PATENT Applicant: WESTFALIA SEPARATOR FOOD TEC GMBH Invention Title: CENTRIFUGE WITH TWIN INLET The following statement is a full description of this invention, including the best method of performing it known to us: 2 Centrifuge With Twin Inlet The invention relates to a centrifuge.

Centrifuges, in particular disk centrifuges, are known having the most varying constructions. When separating cold milk into cream and skimmed milk, the problem, that the cream cannot be discharged from the separator with a stripping disk due to processing reasons, arises. For this reason separators used for this purpose are generally provided with slide ring seals for the inlet and outlet.

By installing slide ring seals the inlet crosssections (diameters) are greatly restricted, since the 0000 15 diameters of the slide ring seals is limited due to their maximum circumferential and rubbing speeds.

:However, to achieve great throughput capacities, the return pressure is to be accordingly increased, necessitating very high pressures by the pumps.

20 Accordingly, the object of the invention is to improve the generic centrifuge in such a manner that the pressures required for the cold milk separation can be reduced with the throughput remaining the same, or the throughput can be increased with the pressures remaining the same.

This objective is achieved by a disk centrifuge, for the separation of cold milk into cream and skimmed milk, including a centrifuge drum with at least one fluid discharge wherein an inlet device constructed concentrically to the axis of rotation of the centrifuge drum for the supply of the material to be centrifuged to the centrifuge drum is provided, characterised in that the N inlet device has two separate inlets which extend into the \\melb_files\home$\paulad\Keep\speci\Centrifuge With Twin Inlet.doc 13/06/01 3 centrifuge drum from opposites portions of the drum concentrically with the axis of rotation of the centrifuge drum; and wherein the drum has a hollow spindle and one of the inlets comprises the hollow spindle, and the other inlet comprises an inlet tube entering the drum from above the centrifuge drum; and wherein both inlets terminate in a common distributor in the centrifuge drum.

According to the invention, the inlet device has two separate inlets, which extend to the centrifugal drum concentrically with the axis of rotation of the centrifugal drum. The "twin" inlet makes it feasible to halve the inlet pressure with the suppled quantity 15 remaining the same in each inlet compared with only one inlet (irrespective whether it terminates at the top of the drum, or, as it is known from the state-of-the-art, at the bottom) or correspondingly increase the throughput capacities with the pressure remaining.

20 The inlet pressure is preferably so adjusted that it is smaller at the top inlet tube than the outlet pressure at the stripping disk-free fluid discharge. In this manner the sealing of the top inlet and of the top inlet tube and of the stripping disk-free fluid discharge can be carried out by means of only one common slide ring seal.

In the preferred embodiment of the invention the inlets terminate in a common distributor in the centrifuge drum and each inlet communicates with a separate inlet channel formed in the distributor. The inlet channels terminate in separate riser channels in a disk packet in the centrifuge. These preferred features have the _advantage that material being fed to the centrifuge drum \\melbfiles\home$\paulad\Keep\speci\Centrifuge With Twin Inlet.doc 13/06/01 3a from the two opposite sides is fed thereto by separate channels in the common distributor and that the separate channels and inlets ensure that the two steams of material fed into the drum do not whirl with each other.

By referring to the drawing an embodiment is described with reference to the accompanying drawings in which; Figure 1 shows a sectioned illustration of a disk centrifuge.

Figure 1 shows a disk centrifuge 2, that has a centrifuge drum 4, that has a tapered narrowing in the top region.

S• In the centre of the centrifuge drum 4 an inlet tube 6 is guided from above (concentrically with the axis 15 of rotation), the tube terminating from above in the lower o region of the centrifuge drum 4 in a distributor 8.

In the lower axial end region of the centrifuge o *o~ g \\melb_files\homeS\paulad\Keep\speci\Centrifuge With Twin Inlet.doc 13/06/01 -4 drum 4 a hollow spindle 11 is formed, onto which the bottom part 10 of the drum is placed and which has at least two bores 13 that terminate in the inlet channels 12, 14 in the distributor.

Thus, the centrifuge drum 4 has two separate inlets which together form the inlet device of the disk centrifuge 2. One inlet channel 12, communicates with the inlet 6 and the other channel 14 communicates with the hollow spindle. The channels 12 and 14 terminate in separate riser channels 16, 18 in the disk packet 20 of the centrifuge drum 4.

For the discharge of two different fluid phases two fluid outlets 22, 24 are provided, one of which is provided with a stripping disk 26 and the other has a 15 stripping disk-free construction.

The disk centrifuge 2 operates as follows: The material to be centrifuged, in particular cold milk, is conveyed to the distributor 8 both through the top inlet tube 6 (arrow B) and the bottom hollow spindle 11 20 (arrow from the distributor the cold milk flows into the inlet channels 12, 14 separated from one another and from there into the riser channels 16, 18 in the disk packet 20 of the centrifuge drum 4.

The skimmed milk is discharged through the fluid 25 outlet 22 with the stripping disk 26, and the cream through the fluid outlet 24 without the stripping disk. A solids discharge 28 makes the removal of solid residues from the centrifuge drum 4 possible.

The sealing of the top inlet and of the top inlet tube 6 and the sealing of the stripping disk-free fluid outlet 24 is carried out by means of only one common slide ring seal 30. This is feasible in particular because the inlet pressure P1 in the top inlet tube 6 is chosen to be \\melb_files\home$S\mbourke\Keep\Speci\Centrifuge With Twin Inlet.doc 01/06/01 smaller than the discharge pressure P2 in the stripping disk-free discharge, so that the load on the seal is unidirectional.

\melb-f ies \home$ \mbourke \Keep\Spec i\Centrifge With Twin Inletdoc 01/06/01

Claims

1. A disk centrifuge, for the separation of cold milk into cream and skimmed milk, including a centrifuge drum with at least one fluid discharge wherein an inlet device constructed concentrically to the axis of rotation of the centrifuge drum for the supply of the material to be centrifuged to the centrifuge drum is provided, characterised in that the inlet device has two separate inlets which extend into the centrifuge drum from opposites portions of the drum concentrically with the axis of rotation of the centrifuge drum; and wherein the drum has a hollow spindle and one of the l: inlets comprises the hollow spindle, and the other inlet 15 comprises an inlet tube entering the drum from above the centrifuge drum; and wherein both inlets terminate in a common distributor in the centrifuge drum. 20 2. A centrifuge according to claim 1, characterised in that each inlet communicates with a separate inlet channel formed in the distributor. *.aa.

3. A centrifuge according to claim 2, characterised in that each inlet communicates with at least one inlet channel in the distributor.

4. A centrifuge according to claim 2 or 3, characterised in that the inlet channels terminate in separate riser channels in a disk packet in the centrifuge drum. \\melb_files\home$\paulad\Keep\speci\Centrifuge With Twin Inlet.doc 13/06/01 7 A centrifuge according to any one of the preceding claims, characterised in that at least one of the fluid discharges has a stripping disk-free construction.

6. A centrifuge according to claim 1, characterised in that the sealing of the inlet tube and the sealing of the fluid discharge is carried out by means of slide ring seals.

7. A centrifuge according to claim 6, characterised in that the sealing of the top inlet and of the fluid discharge is carried out by means of only one common slide ring seal.

8. A centrifuge according to any one of the preceding claims, including two discharge outlets, one of the discharge outlets having a stripping disk and the .999* 0other of the outlets not having a stripping disk.

9. A centrifuge according to claim 8, characterised in that the inlet pressure at one of the inlets is set to be smaller than the outlet pressure at the fluid discharge not having the stripping disk. Dated this 12th day of June 2001 WESTFALIA SEPARATOR FOOD TEC GMBH By their Patent Attorneys GRIFFITH HACK Fellows Institute of Patent and Trade Mark Attorneys of Australia \\melb_files\home$\paulad\Keep\speci\Centrifuge With Twin Inlet.doc 13/06/01