Double-action pusher centrifuge and pusher base device

Abstract

A double-action pusher centrifuge separates a mixture into solid cake and liquid. The pusher centrifuge includes a screen drum rotatable about an axis and in which a pusher base device is arranged to be movable along the axis of rotation. The solid cake is displaced by an outer ring region of the pusher base device. A plurality of axial passage openings are disposed in the outer ring region and connect front and rear regions of the screen drum. A feed unit is arranged at an inflow disk such that the mixture can be introduced via the feed unit and the inflow disk into empty space on the screen drum on displacement of the solid cake. An inflow gap applies the mixture into the empty space, and is between an inflow edge of the inflow disk and a pusher base plate of the pusher base device with an inflow region.

Claims

1. A double-action pusher centrifuge for separating a mixture into a solid cake and a liquid, the double-action pusher centrifuge comprising: a screen drum including a front region and a rear region, and being rotatable about an axis of rotation; a pusher base device including an outer ring region, being disposed in the screen drum, and being movable to and fro along the axis of rotation so as to alternately displace the solid cake in the screen drum by the outer ring region in an operating state; a plurality of axial passage openings disposed in the outer ring region of the pusher base device, and connecting the front region and the rear region of the screen drum; an inflow disk; a feed unit arranged at the inflow disk, and the feed unit and the inflow disk being configured to introduce the mixture via into an empty space arising on the screen drum on displacement of the solid cake; and an inflow gap which is not interrupted in a peripheral direction, being configured to apply the mixture into the empty space on the screen drum, and being disposed between an inflow edge of the inflow disk and a pusher base plate of the pusher base device with an inflow region, the inflow edge of the inflow disk being disposed within the axial passage openings.

2. A double-action pusher centrifuge in accordance with claim 1, wherein the inflow gap is a peripheral inflow groove in the pusher base plate.

3. A double-action pusher centrifuge in accordance with claim 1, wherein the inflow gap is a spacing gap between the inflow edge and the pusher base plate.

4. A double-action pusher centrifuge in accordance with claim 2, wherein the inflow edge extends into the inflow groove.

5. A double-action pusher centrifuge in accordance with claim 1, further comprising a preacceleration device configured to preaccelerate the mixture in the inflow region of the pusher base device.

6. A double-action pusher centrifuge in accordance with claim 5, further comprising a valve ring disposed in the inflow region between the preacceleration device and the screen drum.

7. A double-action pusher centrifuge in accordance with claim 1, further comprising a flushing pipe extending into the screen drum through the feed device and through the pusher base device form the front region into the rear region of the screen drum, and being configured to introduce at least one of washing liquid and flushing liquid into the screen drum.

8. A double-action pusher centrifuge in accordance with claim 1, wherein the pusher base device has a double-walled configuration in the outer ring region.

9. A double-action pusher centrifuge in accordance with claim 8, wherein the ring region includes a termination band in a direction toward the screen drum.

10. A double-action pusher centrifuge in accordance with claim 8, wherein the passage openings of the ring region are open in a direction toward the screen drum.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The invention will be explained in more detail in the following with reference to the schematic drawings.

(2) FIG. 1a is a double-action pusher centrifuge known from the prior art;

(3) FIG. 1b is a detailed drawing of a pusher base device in accordance with FIG. 1a;

(4) FIG. 1c is a detail in accordance with FIG. 1b;

(5) FIG. 1d is the pusher base device in accordance with FIG. 1c from the direction of view A;

(6) FIG. 2 is a first embodiment of a double-action pusher centrifuge in accordance with the invention;

(7) FIG. 3 is a second embodiment of a double-action pusher centrifuge in accordance with the invention;

(8) FIG. 4 is a third embodiment with a distribution ring and a preacceleration device;

(9) FIG. 5 is a fourth embodiment with a flushing pipe;

(10) FIG. 6 is a pusher base device in accordance with the invention of double-wall design with a termination band; and

(11) FIG. 7 is a pusher base device in accordance with the invention of double-wall design with an outwardly open ring region.

DETAILED DESCRIPTION OF EMBODIMENTS

(12) FIGS. 1a to 1d show an example of a double-action pusher centrifuge which is known from the prior art, which was already initially discussed in detail and which therefore no longer has to be discussed at this point.

(13) FIG. 2 shows in section in a highly schematic representation, major components of a first embodiment of a double-action pusher centrifuge in accordance with the invention by way of example. In this respect, the double-action pusher centrifuge of the present invention can be considered as a further development of the known double-action pusher centrifuge in accordance with FIG. 1a-FIG. 1d at least for special embodiments, with the major difference being able to be seen in the inflow gap which is not interrupted in the peripheral direction and which is lacking in the known double-action pusher centrifuges.

(14) The double-action pusher centrifuge in accordance with the invention of FIG. 2, which is designated by the reference numeral 1 in total, serves for the separation of a mixture 17 into a solid cake 14, 15 and into a liquid 39.

(15) The double-action pusher centrifuge 1 comprises in a manner known per se a screen drum 6 which is rotatable about an axis of rotation 10 and in which a pusher base device 5 is arranged movable to and fro along the axis of rotation 10 so that the solid cake 14, 15 is displaceable alternately in the screen drum 6 in the operating state by means of an outer ring region 51 of the pusher base device 5. A plurality of axial passage openings 12 are provided in the outer ring region 51 of the pusher base device 5 which connect a front region 151 and a rear region 141 of the screen drum 6. Furthermore, a feed unit 11 arranged at an inflow disk 29 is provided at the pusher base device such that the mixture 17 can be introduced via the feed unit 11 and the inflow disk 29 into the empty space 16 arising on the screen drum 6 on a displacement of the solid cake 14, 15. In accordance with the present invention, an inflow gap 53 which is not interrupted in the peripheral direction U and via which the mixture 17 can be applied into the empty space 16 on the screen drum 6 is formed between an inflow edge 291 of the inflow disk 29 and a pusher base plate 52 of the pusher base device 5 with an inflow region 500.

(16) In the specific embodiment of FIG. 2, the inflow gap 53 is configured in the form of a peripheral inflow groove 531 in the pusher base plate 52. The inflow groove 531 can e.g. be milled into the body of the pusher base plate 52 in the peripheral direction U in the region of the passage openings 12. The inflow edge 291 extends into the peripheral inflow groove 531, whereby the mixture 17 can be preaccelerated within the inflow gap 53 and the passage openings 12 as well as further components are loaded correspondingly less by wear.

(17) FIG. 3 shows a second embodiment of a double-action pusher centrifuge 1 in accordance with the invention in which in contrast to the example of FIG. 2 the inflow groove 531 is missing and instead the inflow gap 53 is formed as a spacing gap 532 between the inflow edge 291 and the pusher base plate 52, with the remaining components of the double-action pusher centrifuge 1 of FIG. 3 otherwise in principle being configured analog to the corresponding components of the double-action pusher centrifuge 1 in accordance with FIG. 2.

(18) FIG. 4 shows a third embodiment having a distribution ring 502 and a preacceleration device 501. The preacceleration device 501 in this respect serves for the further improvement of the preacceleration of the mixture 17 in the inlet region 500 of the pusher base device 5. The vanes of the preacceleration device 501 can in this respect, for example, be formed spirally outside the feed unit 11. In addition, a distribution ring 502 is provided between the preacceleration device 501 and the screen drum 6 at a somewhat larger diameter in the inflow region 500. The distribution ring 502 in this respect allows an even more uniform distribution of the mixture over the pusher base plate 52. It is self-explanatory in this respect that in very specific embodiments, only the distribution ring 502 or only the preacceleration device 501 can also be present and both the distribution ring 502 and the preacceleration device 501 can e.g. also advantageously be used in an embodiment in accordance with FIG. 2 with an inflow groove 531.

(19) A fourth embodiment in accordance with the invention with a flushing pipe S is shown by way of example with respect to FIG. 5, the flushing pipe extending through the feed device 11 and through the pusher base device 5 from the front region 151 into the rear region 141 of the screen drum 6 for the introduction of washing and/or flushing liquid into the screen drum 6. Here, the vanes of the preacceleration device 501 are now assembled over a somewhat larger diameter so that there is still sufficient space available for the flushing pipe S. The flushing pipe S can naturally likewise advantageously be used in an embodiment in accordance with FIG. 2 with an inflow groove 531.

(20) A pusher base device 1 in accordance with the invention with a double-wall design and with a termination band 35 is shown schematically with reference to FIG. 6. At least the outer ring region 51 in this respect has a double-wall design and is equipped with a termination band 35 in the direction toward the screen drum 6. The pusher base device 5 of FIG. 6 can specifically be configured as a weld construction in which the feed unit 11 feeds the mixture 17 in the center of the hollow pusher base plate 52, wherein the two plates of the pusher base plate 52 are connected via a termination band 35 at their periphery.

(21) In contrast, FIG. 7 shows a pusher base device 1 in accordance with the invention of double-wall design with an outwardly open ring region 51. The passage openings 12 of the ring region 51 of double-wall design are, as can easily be recognized, open at their periphery in the direction toward the screen drum 6, i.e. in particular the termination band 35 is missing in contrast to the embodiment of FIG. 6.

(22) It is self-evident that the features of the particularly preferred embodiment variants of embodiments in accordance with the invention previously described by way of example can also be advantageously correspondingly combined as desired in a suitable manner in dependence on the demand and that the skilled person easily understands that further non-inventive further developments are also covered by the claimed protective scope.