Centrifuge comprising a paring disc

Abstract

The invention relates to a centrifuge by means of which, during operation in a centrifugal field, a product (P) to be processed can be separated into at least two phases which have different densities and of which at least one phase is a liquid phase (LP), the centrifuge comprising at least the following: a rotatable centrifugal drum having an axis of rotation; at least one paring disc which is arranged in a paring disc chamber and is designed to discharge the at least one liquid phase (LP) from the rotating centrifugal drum during operation, the paring disc comprising a cylindrical disc portion and preferably a shaft portion, one or more discharge channels (17a, 17b,...) being formed in the disc portion, characterised in that the discharge channels (17a, 17b,...) are each limited in the circumferential direction by movable blade elements (191, 192,...), as a result of which the maximum radius of the discharge channels (17a, 17b,...) can be variably adjusted.

Description

[0001] Centrifuge with a peeling disc

[0002] The invention relates to a centrifuge according to the preamble of claim 1.

[0003] Centrifuges are frequently equipped with one or more skimming discs – also called grippers. These skimming discs serve to discharge a flowable phase from the rotating centrifugal drum. According to the prior art – and also according to the invention – such skimming discs are used for liquid discharge in separators with a vertical axis of rotation as well as in other centrifuges such as solid-bowl screw centrifuges.

[0004] The peeling disc, which remains stationary during centrifugal operation, has one or more curved, often crescent-shaped discharge channels. These open radially inwards into axial discharge channels in a peeling disc shaft. The peeling disc is located in a peeling disc chamber, which rotates with the drum and is in fluid communication with the separation chamber of the centrifuge. The peeling disc chamber is thus filled with the separated and discharged liquid phase up to a certain radius.

[0005] The peeling disc is immersed in this rotating liquid phase. Peeling discs operate on the principle of a centripetal pump, in which the impeller is stationary and the liquid rotates around it within the peeling disc chamber (see, for example, Fig. 5). The impeller has discharge channels that extend into the rotating liquid column of the drum at the outer diameter of the peeling disc and capture the product there. The liquid is then conveyed via the crescent-shaped discharge channels to the center of the peeling disc and subsequently directed through further discharge channels in its shaft to a discharge outlet. Preferably, the liquid then exits the centrifuge under pressure through the discharge outlet.

[0006] The number of discharge channels can be determined by the geometry of the gripper or the requirements for pressure and flow rate. Typically, according to the prior art and also according to the invention, one to ten discharge channels are implemented.

[0007] The centripetal pump operates on the principle that the kinetic energy of the rotating liquid column within the drum or disc chamber is redirected and converted into pressure upon entering the disc, thus pumping the liquid. The pumping capacity depends on the diameter of the disc, the drum speed, and the available flow cross-section, which is the sum of the individual cross-sections of all crescent-shaped channels in the disc. These varying parameters allow for a wide range of disc designs. Therefore, discs can be individually tailored to the application and the desired operating point of the centrifuge.

[0008] The conveying capacity of the peeling disc therefore depends, among other things, on the diameter or radius of the peeling disc, the drum speed (rotating liquid phase), the number of discharge channels in the peeling disc and their cross-section.

[0009] The operating range of peeling discs is limited due to their static design. Therefore, attempts are made to design peeling discs with the widest possible operating range. However, as a rule, the peeling disc becomes inefficient as soon as it is operated at the edge of its operating range, since the efficiency decreases there. The primary consequence of this is increased energy consumption required to pump material at this operating point. Another disadvantage that can arise is that cavitation occurs due to the suboptimal flow of material to and through the peeling disc. In the worst case, the cavitation attacks the material of the peeling disc, causing damage. The pumped product is also affected by the cavitation.

[0010] However, in process engineering applications, it is often unavoidable to operate the peeling disc at the edge of its operating range, as this offers other process-related advantages. For example, reducing the rotational speed exposes products to less centrifugal force, thus handling them more gently. A reduced rotational speed also results in less heat input into the product.

[0011] Another aspect that leads to the utilization of the peeling disc's entire operating range is the execution of cleaning processes. During CIP cleaning, some applications require a flow rate through the machine that is 5-6 times higher than that used in regular production. The peeling disc must therefore be designed to handle this increased flow rate during CIP. However, this results in the gripper operating at the lower end of its operating range during regular production, thus operating at a low capacity.

[0012] German patent DE 10 2018 114 843 A1 describes a peeling disc for a centrifuge, whereby, according to this prior art, the width of the peeling disc channels increases radially from the outer circumference of the peeling discs to the inner radius over their entire length. The cross-section of the peeling disc channels, defined by the fixed height, remains unchanged. The conveying capacity of the peeling disc can only be altered by replacing the existing peeling disc with a new one with a different geometry (e.g., diameter of the peeling disc, cross-sections of the discharge channels, and / or number of discharge channels).

[0013] Another peeling disc, based on the state of the art, is described in DE10 2016 115 557 A1. Here, the peeling disc is not fixed to the frame as usual, but is rotatably mounted and equipped with its own drive. By changing the differential rotational speed between the drum and the peeling disc, the conveying capacity of the peeling disc can be altered. A disadvantage of this design is that it significantly increases the complexity of draining the liquid phase from the centrifuge.

[0014] In addition to the possibility of replacing the peeling disc as in DE10 2018 114 843 A1 (different diameter and / or different cross-section of the gripper channels and / or different number of gripper channels) and the possibility of a drive for the peeling disc (DE10 2016 115 557 A1), the following solutions exist in the prior art:

[0015] The EP2627451 B1 and the EP2627452B1 each feature a single adjustable peeling tube. Here, the radius on which the inlet opening of a single rotatably mounted peeling tube is located is adjusted by means of a gear drive.

[0016] DE102018105079A1 discloses a linear drive that acts on the axis of rotation of a rotatably arranged peeling tube and adjusts the radius on which the inlet opening of a single peeling tube is located.

[0017] WQ0074858A1 discloses a single, rotatably arranged peeling tube, wherein the drive is located in the axis of rotation of the peeling tube and adjusts the radius on which the inlet opening of a single peeling tube is located. The drive is a spring drive.

[0018] US4594166 also reveals a single adjustable peeling tube, with the drive acting on the axis of rotation of the peeling tube and adjusting the radius on which the inlet opening of a single peeling tube is located.

[0019] EP 0 612 270 B1 discloses a plurality of tangentially displaceable tubes of a gripper, wherein the inlet of the tubes can be shifted to different diameters.

[0020] And in DE1942490U, it is proposed to adjust the radius on which the inlet opening of a single peeling disc discharge channel is located. The radius can be changed by allowing the gripper to be radially displaced on an eccentric by means of a rotatable inlet pipe.

[0021] Therefore, it is desirable to be able to easily change the conveying capacity of the peeling disc while the centrifugal drum is in operation, as well as to be able to easily adjust the conveying capacity of the peeling disc.

[0022] The invention solves this problem through the subject matter of claim 1. It also creates the method of claim 12.

[0023] According to claim 1, a centrifuge is provided with which a product P to be processed can be separated in a centrifugal field into at least two phases of different densities, at least one of which is a liquid phase, wherein the centrifuge has at least the following: a rotatable centrifugal drum with an axis of rotation, at least one peeling disc arranged in a peeling disc chamber, which is provided for discharging the at least one liquid phase from the rotating centrifugal drum during operation, wherein the peeling disc has a cylindrical disc section - with a preferably first, larger diameter - and preferably a cylindrical shaft section - with a preferably second, smaller diameter - and wherein one or more discharge channels are formed in the disc section.It is further provided that the discharge channels are each limited in the circumferential direction by movable blade elements, which are movable in such a way that the maximum radius of the discharge channels can be adjusted.

[0024] Since the blade elements are movable – for example, sliding and / or pivoting – allowing for the adjustment of the maximum radius of the outlet channels, a simple method for changing the peeling disc's conveying capacity while the centrifugal drum is running is achieved, as is easy adjustment of the peeling disc's conveying capacity. "In the circumferential direction" here means both in and against the circumferential direction, i.e., in and against the direction of rotation of the drum.

[0025] In a particularly preferred embodiment, the disc section of the peeling disc can comprise at least one disc cover part and one disc base part, wherein one or more discharge channels are formed between the disc cover part and the disc base part, and the blade elements are pivotably arranged between the disc cover part and the disc base part about respective axial axes of rotation, so that the maximum radius to which the blade elements extend is variably adjustable, thereby allowing the maximum radius of the discharge channels to be variably adjusted. In this way, the radius of the inlet of the at least one or more discharge channels can be changed in a particularly simple manner.

[0026] The centrifuge of this type is currently being further developed in such a way that it is possible to use the peeling disc in such a way that only as much pressure and flow rate as is required for the respective process is generated in the channels of the peeling disc in a simple manner.

[0027] In this document, the terms "axial," "radial," and "radius" refer—as far as the peeling disc is concerned—to the axis or centerline of the stationary peeling disc section and the peeling disc shaft. The peeling disc base part can also be called the disc base part, and the peeling disc cover part can also be called the disc cover part.

[0028] According to a preferred optional embodiment, the blade elements between the disc cover part and the disc base part can be pivotably arranged about their respective individual axial axes of rotation, so that the maximum radius to which they extend can be variably adjusted.

[0029] According to a preferred optional embodiment, the blade elements can be arranged to pivot about their respective individual axial axes of rotation in their radially inner end regions between the disc cover part and the disc base part. It is expedient and advantageous if, according to a further preferred optional embodiment, the blade elements—particularly together and especially preferably even synchronously together—are pivotable by means of one or more mechanical adjustment devices, each comprising one or more drives.

[0030] And it is also practical and advantageous if the drive can be controlled by means of a control device.

[0031] The adjustment mechanism and drive can be implemented in a variety of ways.

[0032] The mechanical adjustment device can thus have rotary rods that are non-rotatably connected to the blade elements, which are coupled to the drive and which are arranged in such a way that the maximum radius of the discharge channels can be changed by pivoting these rotary rods by changing the position of the blade elements.

[0033] And / or the mechanical adjustment device may be designed to pivot the disc cover part relative to the disc base part, wherein the blade elements are coupled to the disc cover part or the disc base part in such a way that by pivoting the disc cover part relative to the disc base part the maximum radius of the discharge channels can be changed by changing the position of the blade elements.

[0034] The drive(s) can preferably be electric, piezoelectric, but also hydraulic or pneumatic. It is important that the maximum radius and preferably also the angle of attack of the blade elements relative to the flow in the peeling disc chamber can be adjusted by the drive(s) during operation and / or when the centrifugal drum is at rest. This is because the blade elements are preferably curved in an arc, so that the discharge channels also preferably run in an arc and / or crescent shape from radially inward to radially outward in the circumferential direction.

[0035] Each centrifugal drum has an inlet pipe leading to the supply of the product to be processed.

[0036] The invention also provides a method for controlling or regulating the operation of a centrifuge according to one or more of the related claims, wherein the method comprises automated pivoting of the blade elements to adjust the radius of the inlet openings of the discharge channels during operation—during rotation and centrifugal processing—and / or when the centrifugal drum is stationary. In a first operating mode, a product is fed into the centrifugal drum, which is rotated so that the product—a free-flowing suspension—is separated into different product phases in the centrifugal field, one of which is a free-flowing phase that is discharged by the peeling disc.

[0037] In this way, the peeling disc can convey material with maximum efficiency at virtually any operating point. This ensures minimal energy consumption and optimal inflow and outflow through the channels. This is possible because the operating range of the peeling disc can be shifted during the process. This is achieved by variably adjusting the maximum radius of one or more discharge channels within the peeling disc.

[0038] Following further training, it is possible, particularly in an additional operating mode for CIP cleaning, to automatically swivel the blade elements to an optimized CIP rotation position for performing CIP cleaning at high fluid throughput. For CIP cleaning, a large outer radius of the skimming disc is advantageous – meaning a rotation position of the blade elements corresponding to a large outer radius of the discharge channels – whereas in normal production and lower fluid throughput, a smaller outer radius of the skimming disc is advantageous to ensure better flow and prevent cavitation.

[0039] Furthermore, adjusting the outer radius of the discharge channels can influence the discharge pressure of the liquid phase, since a smaller outer radius of the discharge channels reduces the discharge pressure and thus the drive energy required for the drum. In this way, the discharge pressure can be reduced to the lowest value required for the process engineering requirements.

[0040] Further advantageous embodiments of the invention can be found in the remaining dependent claims.

[0041] The invention is described in more detail below with reference to the drawings. They show:

[0042] Fig. 1 in 1 a) a partially cut-away side view of a first embodiment of a peeling disc with a disc base part and a disc cover part, on which a peeling disc shaft is arranged and with elements of an adjustment device and in 1 b) a perspective view of the peeling disc base part from 1a);

[0043] Fig. 2 in 2a) a top view of the arrangement from Fig. 1 b) in a first operating position and in 2b) a top view of the arrangement from Fig. 1 b) in a second operating position;

[0044] Fig. 3 in 3a) a top view of another embodiment of a peeling disc base part with elements of an adjustment device in a first operating position and in 3b) a top view of the arrangement from Fig. 3a) in a second operating position;

[0045] Fig. 4 in 4a) a perspective view of the arrangement from Fig. 3b) in the second operating position and in 4b) a perspective view of the embodiment of a disc cover part with a peeling disc shaft and with elements of an adjustment device; and

[0046] Fig. 5 shows a sectional view of a centrifuge that could be, or is, equipped with one of the peeling discs shown in Figs. 1 to 4.

[0047] The following description of the figures describes exemplary embodiments of the invention. Individual features of this exemplary embodiment can also be combined with exemplary embodiments not shown and are also suitable as advantageous embodiments of the features and / or objects described in one or more of the main and dependent claims.

[0048] Terms such as "top," "bottom," "right," "left," "horizontal," "vertical," "radial," "axial," "inside," or "outside" refer to the representation of the figures. When the central axis or axis of rotation A is oriented obliquely in space or horizontally, these terms must be translated to the orientation of these axes of rotation and considered analogously. Fig. 5 shows a rotatable centrifuge drum 1, which is designed as a separator with a vertical axis of rotation A. However, the separator could also have an axis of rotation oblique to the vertical.

[0049] In addition to the centrifugal drum 1, the separator also has other components - shown here only partially and not in their entirety - such as a control computer, a drive motor for rotating the centrifugal drum 1, a drain 24, a hood 33 and a solids trap 34 and possibly other components.

[0050] The drive motor (not shown here) is designed to drive or rotate the rotatable centrifugal drum 1 during operation. This is preferably done via a driven, rotatably mounted drive spindle 35, which is arranged vertically and thus has a vertically oriented axis of rotation A. The centrifugal drum 1 is preferably—but not necessarily—designed for continuous operation, i.e., the continuous and non-batch processing of a product P. The centrifugal drum 1 can have a lower drum section 2 and an upper drum section 3. These can be connected to each other in a rotationally fixed manner by means of a screw connection or the like.

[0051] In the conical, or in this case even doubly conical, drum interior 5 or separation chamber of the centrifugal drum 1, a stack of separating plates 6 made of conical separating plates 7 is arranged. The separating plates 7 are arranged on a distributor shaft 8 of a distributor 9.

[0052] A feed pipe 10 serves to supply a suspension to be processed as the product P. The feed pipe 10 is designed here as a stationary element that does not rotate during operation. It extends concentrically to the axis of rotation A into the centrifugal drum 1.

[0053] According to Fig. 5, in a preferred - but not mandatory - embodiment, the inlet pipe projects from above into the centrifugal drum 1. However, it could also extend from below into the centrifugal drum 1.

[0054] The free-flowing product P to be processed is continuously fed through the feed pipe 10. The product P flowing out of the free end of the feed pipe 10 flows into radially extending distribution channels 11 of the distributor 9 and is rotated or accelerated circumferentially within these channels due to the rotation of the centrifugal drum 1. The distribution channels 11 open into the drum interior 5 containing the stack of discs 6. Within the drum interior 5 – also called the centrifugal chamber – the product P to be processed is separated into at least two phases in a centrifugal field, at least one of which is a liquid phase LP. In the example shown in Fig. 5, the product P is clarified into a (generally sludge-like, still free-flowing) solid phase SP and a liquid phase LP.Alternatively, separation into two or more liquid phases and preferably a solid phase of higher density is also possible (three-phase separator or three-phase decanter or the like - not shown here).

[0055] The solids SP are ejected from the centrifugal drum 1 to the outside through circumferentially distributed, radially extending outlet openings 12, preferably in the area of ​​the largest radius / circumference of the centrifugal drum 1.

[0056] The outlet openings 12 can be designed as nozzles through which solids are continuously ejected (not shown). Alternatively, they can also be equipped with an opening and closing mechanism. According to Fig. 5, a hydraulically actuated piston valve 4 is provided in the lower part of the drum 2, with which the outlet openings 12 can be opened and closed discontinuously.

[0057] Figure 5 shows an example of a single liquid outlet into and through a discharge 18. The liquid phase LP, flowing radially inwards from the stack of plates 6, enters a peeling disc chamber 13, which rotates with the centrifuge drum 1 in a direction DR and is formed here as the upper, closing part of this centrifuge drum 1. A peeling disc 14 – also referred to as a gripper – is arranged in the peeling disc chamber 13. This peeling disc 14 is stationary in the peeling disc chamber 13, e.g., non-rotatably mounted on the feed pipe 10. It has a center line M (see Figure 4). This center line is aligned with the axis of rotation D when the chamber is stationary. The peeling disc 14 is designed to capture and discharge the liquid phase LP from the centrifuge drum 1, so that the liquid phase LP leaves the centrifuge drum 1 through the discharge 24. The peeling disc 14 operates according to the principle of a centripetal pump.

[0058] The peeling disc 14 has a cylindrical disc section 15 with a first, larger diameter and a cylindrical shaft section 16 with a second, smaller diameter. The cylindrical disc section 15 then comprises a disc base part 151 and a disc cover part 152. According to Fig. 5, the disc base part 151 can be formed together with a radially inner shaft section 161 as a pre-assembled unit or in one piece, and the disc cover part 152 can be formed together with an outer shaft section 162 as a pre-assembled unit or in one piece.

[0059] Furthermore, one or more, e.g. two or four, drainage channels 17 are formed in the disc base part, which may be limited downwards and upwards by the disc base part 151 and the disc cover part 152 and which may be limited in the circumferential direction and against the circumferential direction by vertical wall sections (not shown in Fig. 5).

[0060] The drainage channels have an external inlet 171, then extend radially inwards, where they open into one or more axially extending drainage channels 163 of the shaft section 16. These then open outside the drum 1 into a drain 18 (which may, for example, be designed as a drainage pipe).

[0061] According to the known state of the art, these vertical wall sections can be designed vertically or axially and be rigidly connected to the disc base part 151 and the disc cover part 152.

[0062] The radial inlets 171 of the drainage channels 17 serve to skim off the liquid phase in the peeling disc chamber 13 and direct it radially inwards in the disc base part 151. These drainage channels generally run radially in an arc shape from the outside to the inside.

[0063] In centrifuges according to the invention, which may be designed, for example, as shown in Fig. 5 or in other configurations, at least one peeling disc chamber 13 with a peeling disc 14 is provided. This is then replaced by one of the peeling discs 14 according to claim 1 – for example, by one of the peeling discs 14 shown in Figs. 1a, b and 2a, b or 3a, b and 4a, b. However, several peeling disc chambers 13 and several peeling discs 14 may also be provided.

[0064] The peeling discs 14 according to the invention can each have a cylindrical disc section 15 with a first, larger diameter and a cylindrical shaft section 16 with a second, smaller diameter (Fig. 1a). The cylindrical disc section 15 also has a disc base part 151 and a disc cover part 152. The disc base part 151 and the disc cover part 152 can each be plate-like.

[0065] According to Figs. 1a to 4b, the disc base part 151 can optionally be connected to a radially inner tubular shaft section (not shown here) and the disc cover part 152 can optionally be connected to an outer tubular shaft section 162 (Fig. 1a).

[0066] The disc base part 151 and the disc cover part 152 can each be ring-shaped. They thus have an outer diameter and an inner diameter.

[0067] The disc base part 151 and the disc cover part 152 may also preferably have the same outer diameter and be preferably aligned with each other in the axial direction (Fig. 1 a).

[0068] Furthermore, discharge channels 17 or 17a, 17b, 17c, 17d – four shown here as examples – are formed in the disc section 15, which can penetrate the disc section 15 radially from the outside to the inside. The discharge channels 17a, 17b, 17c, 17d are also bounded downwards and upwards by the disc base part 151 and the disc cover part 152, and circumferentially bounded on both sides and in and against the circumferential direction by movable, in particular pivotable, wall sections. These pivotable wall sections – in the orientation of the figures with a vertical axis of rotation A, they are vertical wall sections – are formed here as four blade elements 191, 192, 193, 194, each of which is pivotable about an axial – here vertical – axis of rotation A1, A2, A3, A4.

[0069] The blade elements 191, 192, 193, 194 can be curved.

[0070] They are preferably arranged circumferentially between the disk base part 151 and the disk cover part 152, and preferably in the same direction. Four of the blade elements 191, 192, 193, 194 are shown here by way of example. However, a different number of blade elements 191, 192, 193, 194 can also be arranged circumferentially between the disk base part 151 and the disk cover part 152. The blade elements 191, 192, 193, 194 bear against or almost against the disk base part 151 and the disk cover part 152 at the top and bottom, but are movable relative to them. The blade elements 191, 192, 193, 194 can taper slightly radially from the inside out.The blade elements 191, 192, 193, 194 are each preferably pivotably mounted in their inner end region in a respective joint section – particularly in a further axially inner region – of the disc base part 151 and / or the disc cover part 152 of the cylindrical disc section 15 and extend from there essentially radially outwards. In this way, an axis of rotation A1, A2, A3, A4 is defined for each of the blade elements. In the region of each axis of rotation A1, A2, A3, A4, a rotary rod 1911, 1921, 1931, 1941 is arranged according to Fig. 1b, which is rotationally fixed to the respective blade element 191, 192, 193, 194 and extends parallel to the axis of rotation A of the centrifuge.

[0071] These rotary rods 1911, 1921, 1931, 1941 can be rotatably mounted in corresponding bearing openings of the disc base part 151 and the disc cover part 152 and extend axially upwards here beyond the disc cover part 152.

[0072] The rotary rods 1911, 1921, 1931, 1941 are thus rotatably mounted in the disc section 15 and are preferably guided through the shaft section 16 up to and over the peeling disc 14. There, a torque can be transmitted to the rotary rods 1911, 1912, ... via an external drive, which is not shown in detail here, so that they rotate by an angle β. This rotational movement is then transmitted by the axis of rotation to the blade elements 191, 192, ..., which rotate by the same angle β.

[0073] By rotating the respective rotary rod 1911, 1921, 1931, 1941, the respective blade element 191, 192, ... can also be pivoted. Preferably, all rotary rods 1911, 1921, 1931, 1941 are rotated synchronously. The drive of the rotary rod 1911, 1921, 1931, 1941 can comprise gear elements and one or more drive motor(s).

[0074] The drive, in particular the drive motor, can also be coupled to the centrifuge's control unit and controlled by a control program for the centrifuge or the centrifugal processing, which may include one or more program routines for controlling the blade elements or the drive of the blade elements. This can be done, for example, depending on the product feed rate, cavitation detection, or other measured values.

[0075] The blade elements 191, 192, 193, 194 extend from their axes of rotation

[0076] A1, A2, A3, ... essentially radially outwards. They can preferably have such a radial extent that they can be pivoted into a first pivot position (Fig. 2a) in which they extend radially to the outer edge of the disc base part 151 and the disc cover part 152 (radius R1). And starting from this position, in which the drainage channels 17a, 17b, 17c, ... have their maximum radial extent, they can preferably be pivoted against the direction of rotation of the drum, so that their outer radii then lie on a smaller radius R2 than in the first pivot position of maximum radial extent (Fig. 2a, diameter R1).

[0077] This can be clearly seen by comparing figures 2a and 2b.

[0078] The radial inlet areas or openings 171a, 171b, 171d, 171 of the discharge channels 17a, 17b, 17c, 17d, which serve to skim off the liquid phase in the gripper chamber and guide it radially inwards in the disc base part 151, where they open into axially extending drainage channels of the shaft section 162, are thus adjustable to different radii R1, R2 by means of a mechanical adjustment device.

[0079] In Figures 1a-2b, as well as in Figures 3a to 4b (which will be described later), the drum 1 rotates clockwise, and thus the liquid in the peeling disc chamber 13 also rotates clockwise. The liquid is pressed against the concave side of the paddle elements 191, 192, ... and directed to the center of the peeling disc 14.

[0080] The blade elements 191 , 192,... can be adjusted by means of the mechanical adjustment device at the pivot point by an angle β (see e.g. Fig. 2b), which changes the radius on which the radially outer tips of the blade elements 191 , 192, 193, 194 are located and also changes the flow to the discharge channels 17.

[0081] According to the invention, it is thus possible to adjust the peeling disc 14 in such a way that it conveys with a very good, in particular maximum or almost maximum efficiency at every operating point.

[0082] This ensures that energy consumption is minimized and that optimal flow to and through the discharge channels 17 is achieved. This is only possible because the operating range of the peeling disc 14 is movable during the process. This is realized via the variably adjustable outer radius of one or more discharge channels 17a–17d (Figure 1 shows, for example, four channels) within the peeling disc 14. The mechanical adjustment device shown in Figures 1a to 2b is a preferred, but not the only possible, embodiment of this adjustment device. Figures 3a–4b show a further embodiment.

[0083] In the mechanical adjustment device of Figures 3a and 3b, as well as 4a and 4b, the blade elements 191, 192, 193, 194 are rotatably mounted between the disc base part 151 and the disc cover part 152 of the peeling disc 14 about axes A1 and A2, respectively. These axes can be realized, for example, by means of respective cylindrical pins 1912, 1922, 1932, and 1942, which are each pressed into the disc cover part of the peeling disc 14, which is rigidly fixed in the centrifuge (e.g., connected to the hood 33 of the centrifuge). The disc base part 151 is rotatable about the central axis relative to the disc cover part 152. The blade elements 191, 192, 193, 194 each have a tooth-like lever 21 at their axially inner ends, which is essentially aligned towards the center of the peeling disc 14. This lever 21 is encompassed by a U-shaped bearing receptacle 22, which is firmly connected to the disc base part 151 of the peeling disc 14.The bearing receptacle 22 can be open radially outwards and designed for the positive locking reception of a lever section of the lever, so that the lever 21 can pivot in the bearing receptacle 22.

[0084] In the illustrated embodiment, the disc base part 151 can, for example, be rigidly connected to a shaft section such as the inlet pipe 10 (see Fig. 5), which can be rotated about the axis of rotation A of the centrifugal drum 2 by an external drive (not shown in detail). The angle of rotation is limited in both directions.

[0085] If the shaft section, such as the inlet pipe 10 including the disc base part 151, rotates about the central axis, the lever 21 is deflected by the bearing receptacle 22 by an angle β1 in one direction of rotation and by an angle β2 in the other direction of rotation (Figs. 2a, 3b). The angle β refers to the axes of rotation A1, A2, ... of the blade elements 191, 192, 193, 194 (see Figs. 3a and 3b). The deflection of the lever 21 results in a corresponding deflection of the radially outer tips of the blade elements 191, 192, ... beyond their respective axes of rotation A1, A2, .... This changes the respective radii on which the radially outer tips of the blade elements 191, 192, 193, ... lie. In summary, this means that when the disc base part 151 of the peeling disc 14 in Fig. 2a is rotated clockwise, the outer radius of the discharge channels 17a, 17b, ... in the peeling disc 14 decreases.

[0086] Similarly, a counterclockwise rotation of the disc base part 151 of the peeling disc 14 results in an increase in the outer diameter of the discharge channels 17a, 17b, ... in the peeling disc 14. Compare Fig. 3a and 3b.

[0087] These right and left turns are to be understood as assuming the construction shown. Other corresponding designs are possible.

[0088] The operating range of the peeling disc 14 in the process can also be shifted by changing the outer diameter of the gripper or peeling disc discharge channels.

[0089] This drive can be, for example, electromagnetic, piezoelectric, hydraulic or pneumatic and can also include suitable kinematics or an adjustment mechanism.

[0090] The setpoint for such an adjustment (adjustment travel or adjustment force) can be manually specified by the centrifuge operator or derived from the result of a control or regulation process of the centrifuge's control unit. This control or regulation process is carried out by means of a control unit (not shown here) which may be connected to the drive and one or more sensors. Advantageously, this can be used in such a way that a method for controlling or regulating the operation of the centrifuge with the peeling disc shown in Fig. 5, which is equipped with a drive, includes automated adjustment of the blade elements.

[0091] If the centrifuge is fed with a low feed rate [l / h] of the product P to be separated, it may also be advantageous to reduce the cross-section of the discharge channels of the peeling disc 14, as otherwise undesirable pulsating pumping of the peeling disc 14 will occur or cavitation will occur, especially at the inlet edges of the respective blade elements 191, 192, .... which run in relation to the direction of rotation DR of the liquid flow.

[0092] The discharge rate of the peeling disc 14 can be adjusted manually, for example, using a table of values ​​that lists the appropriate angle β of the blade elements depending on the product feed rate P. However, the discharge rate of the peeling disc 14 can also be adjusted automatically in accordance with the aforementioned control process, for example, by using a suitable sensor (not shown here) to detect cavitation. The control device, the appropriately designed control program, and the drive then adjust the position of the blade elements to prevent cavitation.

[0093] The process can be implemented on the control computer. The control and / or regulation process can also include self-learning optimization routines. For example, the process can also be optimized using an artificial intelligence (AI) system. This involves acquiring parameters of the centrifugal processing and transmitting the parameter values ​​to the AI ​​system. The AI ​​then generates one or more predictions for adjusted operating parameters, including the position of the blade elements 191, 192, 193, ... The centrifuge is then operated further, taking these adjusted operating parameters into account.

[0094] In summary, the respective peeling discs 14 can be advantageously and easily adjusted for different operating points and discharge rates using identical components.

[0095] Reference symbol list

[0096] 1 centrifugal drum

[0097] 2 Drum base

[0098] 3 Drum top

[0099] 4 piston valves

[0100] 5 Drum interior

[0101] 6 stacks of plates

[0102] 7 separating plates

[0103] 8 distribution shaft

[0104] 9 distributors

[0105] 10 Inlet pipe

[0106] 11 distribution channels

[0107] 12 Exit opening

[0108] 13 peeling disc chamber

[0109] 14 peeling discs

[0110] 15 disc section

[0111] 151 Disc base part

[0112] 152 Window cover part

[0113] 16 shaft section

[0114] 161, 162, 163 shaft sections

[0115] 17, 17a, 17b, 17c, 17d discharge channels

[0116] 171, 171a, 172b,... Admission

[0117] 18 drains

[0118] 191, 192, 193, 194 Blade element

[0119] 1911, 1921, 1931, 1941 Swivel rod

[0120] 1912, 1922, 1932, 1942 pencils

[0121] 21 levers

[0122] 22 drivers

[0123] 33 Hood

[0124] 34 solid debris traps

[0125] 35 Drive spindle

[0126] A axis of rotation

[0127] A1, A2, A3, A4 Axis of rotation DR Direction of rotation R1 First radius R2 Second radius P Product LP Liquid phase SP Solid phase β Angle

Claims

Patent claims 1. Centrifuge with which, during operation in a centrifugal field, a product (P) to be processed can be separated into at least two phases of different densities, at least one of which is a liquid phase (LP), wherein the centrifuge comprises at least the following: a) a rotatable centrifugal drum (1) with an axis of rotation (A), b) at least one peeling disc (14) arranged in a peeling disc chamber (13), which is provided for discharging the at least one liquid phase (LP) from the rotating centrifugal drum (1) during operation, c) wherein the peeling disc (14) has a cylindrical disc section (15) and preferably a shaft section (16), d) wherein one or more discharge channels (17a, 17b, ...) are formed in the disc section (15), characterized in that e) the discharge channels (17a, 17b, ...) are each circumferentially guided by movable blade elements (191, 192, ...) are limited, which means that the maximum radius of the discharge channels (17a, 17b, ... ) can be adjusted.

2. Centrifuge according to claim 1, characterized in that the blade elements (191 , 192, ... ) are curved in an arc shape, so that the discharge channels (17a, 17b, ... ) also run in an arc shape and / or crescent shape from radially inside to radially outside in the circumferential direction.

3. Centrifuge according to claim 1 or 2, characterized in that the disc section (15) of the peeling disc (14) comprises at least one disc cover part (152) and one disc base part (151), wherein one or more discharge channels (17a, 17b, ... ) are formed between the disc cover part (152) and the disc base part (151 ), and that the blade elements (191 , 192, ... ) are pivotably arranged between the disc cover part (152) and the disc base part (151 ) about axial axes of rotation (A1 , A2, ... ), so that the maximum radius to which the blade elements extend is variably adjustable, thereby making the maximum radius of the discharge channels (17a, 17b, ... ) variably adjustable.

4. Centrifuge according to claim 3, characterized in that the blade elements (191 , 192, ... ) between the disc cover part (152) and the disc base part (151 ) rotate about their respective individual axial axes of rotation (A1 , A2, ... ) are arranged in a pivotable manner.

5. Centrifuge according to claim 3 or 4, characterized in that the blade elements (191 , 192, ... ) are arranged pivotably in their radially inner end regions between the disc cover part (152) and the disc base part (151) about their respective individual axial axes of rotation (A1 , A2, ... ).

6. Centrifuge according to one of the preceding claims, characterized in that the blade elements (191 , 192, ... ) are pivotable by means of one or each of a mechanical adjusting device which has one or each of a drive.

7. Centrifuge according to claim 6, characterized in that the blade elements (191 , 192, ... ) can be pivoted synchronously together by means of the mechanical adjustment device.

8. Centrifuge according to claim 6 or 7, characterized in that the drive can be controlled by means of a control device.

9. Centrifuge according to one of the preceding claims, characterized in that the mechanical adjustment device has respective rotary rods (1911 , 1921 , ... ) which are connected to the blade elements in a rotationally fixed manner and which are coupled to the drive and which are arranged such that by pivoting these rotary rods (1911 , 1921 , ... ) the maximum radius of the discharge channels (17, 17a, 17b, 17c, 17d) can be changed by changing the position of the blade elements (191 , 192, ... ).

10. Centrifuge according to one of the preceding claims, characterized in that the mechanical adjustment device is designed to pivot the disc cover part (152) relative to the disc base part (151), wherein the blade elements (191 , 192, ... ) are coupled to the disc cover part (152) or the disc base part in such a way that by pivoting the disc cover part (152) relative to the disc base part (151 ) the maximum radius of the discharge channels (17, 17a, 17b, 17c, 17d) can be changed by changing the position of the blade elements (191 , 192, ... ).

11. Centrifuge according to one of the preceding claims, characterized in that the drive(s) is designed to be electromechanical, piezoelectric, hydraulic or pneumatic.

12. Centrifuge according to one of the preceding claims, characterized in that the maximum radius and angle of attack of the blade elements (191 , 192, ... ) are adjustable by the drive(s) during operation and / or when the centrifuge drum (1 ) is at rest.

13. Method for controlling or regulating the operation of a centrifuge according to one or more of the preceding claims, characterized in that the method comprises an automated pivoting of the blade elements (191 , 192, ... ) to adjust the maximum radius of the inlet openings of the discharge channels (17a, 17b, ... ) during operation and / or when the centrifuge drum (1 ) is at rest.

14. Method according to claim 13, characterized in that the method involves an automated pivoting of the blade elements (191 , 192, ... ) to an optimized CIP rotation position for performing CIP cleaning.

Images