Centrifuge comprising a paring disk
Patent Information
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- GEA WESTFALIA SEPARATOR GROUP
- Filing Date
- 2024-11-21
- Publication Date
- 2026-06-17
AI Technical Summary
Existing centrifuges with paring discs require replacement of the disc to change conveying capacity, which is inefficient and increases downtime. Additionally, modifying the conveying capacity while the centrifuge is in operation is complex and not easily achievable.
A centrifuge design featuring a paring disc with a cylindrical disc section and a shaft section, where the disc section is divided into a lower and upper part, allowing the upper part to be axially movable relative to the lower part. This enables the cross-section of the discharge channels to be adjusted during operation, thereby changing the conveying capacity without replacing the disc.
The adjustable paring disc allows for continuous adjustment of the conveying capacity between minimum and maximum values, enhancing operational flexibility and reducing the need for disc replacement, thus increasing productivity and simplifying maintenance.
Smart Images
Figure EP2024083176_05062025_PF_FP_ABST
Abstract
Description
[0001] Centrifuge with a paring disc
[0002] The invention relates to a centrifuge according to the preamble of claim 1.
[0003] Centrifuges are often equipped with a paring disc—also known as a gripper in technical terms. Such centrifuges have been known for a long time. The at least one or two paring discs each serve to discharge flowable phases from the rotating centrifuge drum. For the state of the art, reference is made to DE 43 28 369 A1 and US 2014 / 0341 714 A.
[0004] These impeller discs are used for liquid discharge in both vertical-axis separators and solid-bowl screw centrifuges. This impeller disc operates according to the principle of a centripetal pump.
[0005] The impeller disc, which is stationary during centrifuge operation, has curved or crescent-shaped discharge channels formed at the end of a impeller disc shaft. The impeller disc is surrounded by a impeller disc chamber, which rotates with the drum and is in fluid communication with the centrifuge's separation chamber. The impeller disc chamber is thus filled with the separated liquid phase to be discharged.
[0006] The impeller disc is immersed in this rotating liquid phase. The impeller disc's discharge channels direct the liquid phase to the discharge channels of the impeller disc shaft located in the center, through which the liquid phase is discharged from the centrifuge. During this process, the kinetic energy of the rotating liquid phase is partially converted into pressure, so that in conventional centrifugal separators, pressures of several bar can be generated in the discharge channels.
[0007] The conveying capacity of the peeling disc 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.
[0008] DE10 2018 114 843 A1 describes a rotor disc for a centrifuge. According to this prior art, the width of the rotor disc channels increases in the radial direction from the outer circumference of the rotor discs to the inner radius over the entire extent. The cross-section of the rotor disc channels, defined by the fixed height, is unchangeable. What is in need of improvement is that in a centrifuge with such a rotor disc, the conveying capacity of the rotor disc can only be changed by replacing the existing rotor disc with a new one with a different geometry (e.g., rotor disc diameter, cross-sections of the discharge channels, and / or the number of discharge channels).
[0009] Another state-of-the-art impeller disc is described in DE102018 115 557 A1. Here, the impeller disc is not permanently attached to the frame as usual, but is mounted on a rotatable support and equipped with its own drive. By changing the differential speed between the drum and the impeller disc, the conveying capacity of the impeller disc can be adjusted. The disadvantage of this design is that the complexity of draining the liquid phase from the centrifuge is significantly increased.
[0010] It is therefore 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 easily adjust the conveying capacity of the peeling disc.
[0011] This object is achieved with the subject matter according to claim 1. Thereafter, a centrifuge for centrifugal separation is provided, with which a product P to be processed can be separated into at least two phases of different densities in a centrifugal field, of which at least one phase is a liquid phase, the centrifuge comprising at least the following: a rotatable centrifugal drum with an axis of rotation, at least one paring disc which is provided for discharging the at least one liquid phase from the rotating centrifuge drum during operation, the paring disc comprising a cylindrical disc section with a first, larger diameter and a cylindrical shaft section with a second, smaller diameter, the disc section of the paring disc comprising at least one or more discharge channels.It is further provided that at least the disc section of the peeling disc is designed in a divided manner and has a disc section lower part and a disc section upper part, wherein the disc section upper part is movable relative to the disc section lower part.
[0012] In this way, the cross-section of at least one or more discharge channels can be changed in a simple manner.
[0013] The term axial refers - as far as the paring disc is considered - to the axis or the center line of the paring disc section and the paring disc shaft.
[0014] It is also particularly advantageous that the upper part of the disc section is axially movable relative to the lower part of the disc section, in particular axially raised or lowered, which is particularly easy to implement in terms of design. According to a particularly preferred embodiment, the upper part of the disc section is axially movable relative to the lower part of the disc section by means of a drive, in particular axially raised or lowered (i.e., both are possible depending on the control). This further simplifies the adjustment of the cross-section of the discharge channel.
[0015] The invention is particularly suitable for a centrifuge which is designed as a separator, the centrifugal drum of which rotates during operation about a vertical axis of rotation D in a direction of rotation DR.
[0016] According to a further preferred embodiment, the peeling disc is designed as a stationary element that does not rotate during operation. However, it is also conceivable for the peeling disc itself to rotate at a speed different from that of the centrifuge drum.
[0017] According to preferred and expedient embodiments, the drive is electrically, hydraulically, or pneumatically operated. Alternatively, it can also be manually mechanically operated and / or actuated. For example, it could be designed as a spindle drive that can be manually or motorically operated.
[0018] According to further preferred and expedient embodiments, the cross-section of the discharge channels can be adjusted by the drive during operation and / or when the centrifuge drum is at a standstill. It appears particularly advantageous to be able to adjust this during operation.
[0019] It can then further advantageously be provided that the cross-section of the discharge channels is continuously adjustable by the drive.
[0020] According to a further preferred embodiment, the discharge channels comprise lower section discharge channels and upper section discharge channels, and both the cross-section of the lower section discharge channels and the cross-section of the upper section discharge channels can be changed by displacing the upper section of the disc section relative to the lower section of the disc section. This embodiment simplifies the structural implementation of the adjustability of the cross-section of the discharge channels by the drive, even during operation.
[0021] According to a further advantageous design, the lower part of the disc section has the peeling disc shaft.
[0022] According to a further advantageous embodiment, it is provided that the lower part of the disc section has a base plate and a plurality of crescent-shaped base webs arranged thereon, which extend radially from the inside to the outside in an arc shape, wherein they have a height H1 in the axial direction, wherein the lower part discharge channels are formed in the circumferential direction between the base webs, which extend correspondingly radially from the inside to the outside in an arc shape and which are each delimited downwards by the base plate and upwards by the upper part of the disc section.It can then further advantageously be provided that the disc section upper part has a cover plate, below which a number of engagement webs is formed which corresponds to the number of lower part discharge channel sections of the discharge channels, which extend in an arc-shaped manner radially from the inside to the outside and which have a height H2 in the axial direction, wherein the upper part discharge channels are formed between the engagement webs, which extend in a corresponding arc-shaped manner radially from the inside to the outside and which are each delimited at the top by the cover plate and at the bottom by the disc section lower part.
[0023] According to a further advantageous and preferred embodiment, it can then be further provided that the contour of the engagement webs and the upper part discharge channels of the disc section upper part is mirror-identical to the contour of the base webs and the lower part discharge channels of the disc section lower part, so that the engagement webs of the disc section upper part engage in the discharge channels of the disc section lower part, and the base webs of the disc section lower part engage in the upper part discharge channels and are displaceable there, which changes the cross-section of the lower part discharge channels and the cross-section of the upper part discharge channels. The heights H1 and H2 can be different or the same. If they are the same, the discharge channels can be almost completely closed; if H1, on the other hand, is larger than H2, a certain minimum cross-section remains even in the fully lowered position of the disc section upper part.
[0024] According to a further preferred embodiment, it can be further provided that the base webs of the lower part of the disc section can be inserted into the discharge channels of the upper part of the disc section in a form-fitting manner, and that the engagement webs of the upper part of the disc section can be inserted into the discharge channels of the lower part of the disc section in a form-fitting manner. This allows the cross-section of the discharge channels to be easily and precisely modified.
[0025] It can then further be provided that the cover plate has a central opening and an annular, tubular collar adjoining the side of the cover plate facing away from the engagement webs of the disc section upper part, which is designed such that the disc section upper part is slidably guided radially outwardly on the shaft section of the disc section lower part. This ensures that the disc section upper part is slidably guided on the disc section lower part. It can then further be provided that the shaft section is longer than the collar.
[0026] The collar, which can be moved on the shaft section, is also particularly advantageous when the shaft section has several circumferentially distributed openings at the axial height of the lower and upper discharge channels, which are aligned with the lower and upper discharge channels, especially when the upper part of the disc section is moved from a lower position to an upper position, so that the liquid phase can flow through the lower and upper discharge channels into the circumferentially drained liquid phase through the circumferentially distributed openings into one or more preferably axially extending discharge channels of the shaft section. From these, it is then further drained.
[0027] It can further be provided that the annular collar completely or partially covers the openings in the shaft section like a movable diaphragm when the upper part of the disc section is displaced into an axially lower position. It can also advantageously be provided that a maximum distance A between the two disc section parts can be limited by the drive and / or the adjustment mechanism such that the respective discharge channels and respective webs always overlap axially.
[0028] A further optional feature is that the minimum vertical distance A between the two disc section parts can be limited by the drive and / or the adjustment mechanism such that a defined minimum open cross-section of the discharge channels is still formed by the respective discharge channels and respective webs. By moving the upper part of the disc section, the cross-section of the discharge channels can then be further increased starting from this minimum value.
[0029] However, it can also be provided that the minimum vertical distance A between the two disc section parts is selected such that the respective discharge channels are completely closed by the respective webs.
[0030] In any case, the collar on the upper part of the disc section prevents the openings above the cover plate of the upper part of the disc section from being exposed again if the upper part of the disc section is lowered further. To implement the drive, it can be advantageously and simply provided that the upper part of the disc section is pressed against the lower part of the disc section by a spring, for example a helical spring, until a minimum cross-section of the discharge channels is reached.
[0031] Optionally, according to a further advantageous embodiment, it can then be provided that the upper part of the disc section is adjustable relative to the lower part of the disc section against the spring force, i.e. can be raised or lowered. It is then further expedient if a setpoint or a control or reference variable for an adjustment (adjustment path or adjustment force) can be specified manually by a centrifuge operator or if the setpoint is determined during a control or regulation process with the aid of the centrifuge's control device. In contrast to state-of-the-art paring discs, these variants in particular can cover a considerably larger working range, so that the paring disc needs to be replaced to adapt to the respective requirements and conditions much less frequently than with state-of-the-art paring discs. This advantageously increases the productivity of the centrifuge.
[0032] Finally, a method for controlling or regulating the operation of a centrifuge according to one or more of the preceding claims is also provided, which method comprises an automated adjustment of a relative position between the upper part of the paring disc section and the lower part of the paring disc section. For example, the spring force of the spring or the adjustment path of the upper part of the paring disc section can advantageously be used as a control or reference variable.
[0033] Further advantageous embodiments of the invention can be found in the remaining subclaims.
[0034] The invention is described in more detail below with reference to the drawings.
[0035] It shows:
[0036] Fig. 1 is a perspective view of a lower part of a peeling disc according to the invention;
[0037] Fig. 2 in a) a spatial view of an upper part of a peeling disc according to the invention, in b) a further spatial view of the upper part of the peeling disc from Fig. 2a; Fig. 3 a peeling disc according to the invention in a first position;
[0038] Fig. 4 shows the peeling disc from Fig. 3 in a second position; and
[0039] Fig. 5 is a schematic view in full section through a separator with a
[0040] Peeling disc.
[0041] The following description of the figures describes an exemplary embodiment. Individual features of this exemplary embodiment can also be combined with exemplary embodiments not shown and are also suitable as advantageous embodiments of the subject matter described in one or more of the main and subclaims.
[0042] The terms used below, such as "top," "bottom," "right," "left," "horizontal," "vertical," "radial," "axial," "inside," or "outside," refer to the representation of the figures. They are to be translated to the orientation of the rotation axis D when the axis of rotation D is oriented obliquely in space or horizontally and should be viewed analogously.
[0043] Fig. 5 shows a rotatable centrifugal drum 1 of a centrifuge, which can be designed as a separator with a vertical axis of rotation D. The separator can also have an axis of rotation inclined to the vertical.
[0044] In addition to the centrifugal drum 1, the separator has further components - not all of which are shown here - such as a control computer, a drive motor for rotating the centrifugal drum 1, an outlet 24, a hood 33 and a solids catcher 34 and possibly further components that are not of interest here.
[0045] A drive motor (not shown here) is provided 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 here and thus has a vertically aligned axis of rotation D. The centrifugal drum 1 is preferably - but not necessarily - designed for continuous operation - i.e., the continuous and not batch-wise processing of a product P. The centrifugal drum 1 can have a lower drum section 2 and a drum upper section 3. These can be connected to one another in a rotationally fixed manner via a screw connection or the like.
[0046] A stack of separating plates 6 consisting of conical separating plates 7 is arranged in the conical, or in this case even double-conical, drum interior 5 or separation chamber of the centrifugal drum 1. The separating plates 7 are arranged on a distributor shaft 8 of a distributor 9.
[0047] An inlet pipe 10 serves to supply a suspension or product P to be processed. The inlet pipe 10 is designed here as a stationary element that does not rotate during operation. It extends concentrically to the rotational axis D into the centrifuge drum 1. According to Fig. 5, in a preferred—but not mandatory—configuration, it extends from above into the centrifuge drum 1. However, it can also extend from below into the centrifuge drum 1.
[0048] The flowable product P to be processed is continuously fed through the inlet pipe 10. The product P exiting the free end of the inlet pipe 10 flows into radially extending distribution channels 11 of the distributor 9 and is rotated or accelerated in the circumferential direction as a result of the rotation of the rotating centrifugal drum 1. The distribution channels 11 open into the drum interior 5 with the plate stack 6.
[0049] In the drum interior 5 - also called the centrifugal chamber - a 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 of Fig. 5, the product P is clarified into a solid phase Sp and a liquid phase Lp. Alternatively, a separation into two or more liquid phases Lp1, Lp2 of different densities is also possible.
[0050] The solids Sp are ejected outwards from the centrifugal drum 1 through circumferentially distributed, radially extending outlet openings 12, preferably in the region of the largest radius / circumference of the centrifugal drum 1.
[0051] The outlet openings 12 can be designed as nozzles through which solids are continuously ejected (not shown). Alternatively, they can also be assigned an opening and closing mechanism. According to Fig. 5, a hydraulically actuated piston valve 4 is provided in the drum base 2 for this purpose, with which the outlet openings 12 can be discontinuously opened and closed again.
[0052] According to Fig. 5, a single liquid outlet 24 is provided by way of example. The liquid phase Lp flowing radially inwards from the stack of plates 6 flows into a paring disc chamber 13 which rotates with the centrifuge drum 1 in a direction of rotation DR and is designed here as the upper, final part of this centrifuge drum 1. A paring disc 14 - also referred to in technical terms as a gripper - is arranged in the paring disc chamber 13. This paring disc 14 is arranged stationary in the paring disc chamber 13, e.g. non-rotatably on the inlet pipe 10. It has a center line M (see Fig. 4). This is aligned with the axis of rotation D when stationary. The paring disc 14 is provided to tap the liquid phase Lp from the centrifuge drum 1 and discharge it, so that the liquid phase Lp leaves the centrifuge drum 1 via the liquid outlet 24. The paring disc 14 operates according to the principle of a centripetal pump.It has several discharge channels.
[0053] The peeling disc 14 has a cylindrical disc section 15 with a first larger diameter D1 and a cylindrical shaft section 18 with a second, smaller diameter D2. According to embodiments of the invention, the disc section 15 is divided and thus has a lower disc section part 15a and an upper disc section part 15b, as can be seen in Fig. 3 and Fig. 4. The discharge channels accordingly comprise lower section discharge channels 17 and upper section discharge channels 28.
[0054] In Fig. 1, the disk section lower part 15a is shown without adjacent components. The disk section lower part 15a has a cylindrical envelope geometry with a first, larger diameter D1. The disk section lower part 15a has a base plate 37. On the base plate 37, at least two—here four—sickle-shaped base webs 16 are arranged circumferentially distributed in a spoke-like manner, each in the radial direction.
[0055] The base webs 18 extend almost tangentially or in the circumferential direction. They have a height H1 in the axial direction, with the lower part discharge channels 17 being formed in the circumferential direction between the base webs 16, which extend radially from the inside to the outside in a correspondingly curved manner and are each bounded at the bottom by the base plate and at the top by the upper part of the disc section.
[0056] The radially extending contour of the base webs 18 and the lower part discharge channels 17 is preferably geometrically identical.
[0057] Concentrically to the disc section 15, the shaft section 18 of the peeling disc 14 is formed perpendicularly thereto on the disc section lower part 15a.
[0058] The shaft section 18 also has a cylindrical shell geometry, here with a second, smaller diameter D2. The shaft section 18 can further comprise two concentrically arranged tubes 19, 20, which thus form an annular space 21 between them. This annular space 21 can be divided into several—at least two—here four—outlet channels 23 by circumferentially distributed, radially aligned ribs 22. The shaft section 18 can extend vertically upward from the centrifuge drum 1 and open into the liquid outlet 24 (see Fig. 5), through which the liquid phase Lp is discharged from the centrifuge.
[0059] Fig. 2a and Fig. 2b each show the upper disc section part 15b of the peeling disc 14. The upper disc section part 15b can also have a cylindrical envelope geometry. It has a main axis perpendicular to the disc plane. Relative movements parallel to this main axis are referred to in this document as axial movements. The upper disc section part 15b also preferably has a diameter D1. As a rule, the disc plane is a horizontal plane, and the main axis of the disc extends vertically.
[0060] The disc section upper part 15b has a cover plate 26. Below this, a number of engagement webs 27 are formed, selected according to the number of lower part discharge channels 17, which extend radially from the inside to the outside in an arc shape and have a height H2 in the axial direction. The upper part discharge channels 28 are formed between the engagement webs 27, which extend radially from the inside to the outside in a corresponding arc shape and are each delimited at the top by the cover plate 26 and at the bottom by the disc section lower part 15a. The radially extending contour of the engagement webs 27 and the upper part discharge channels 28 can be geometrically identical.
[0061] The contour of the engagement webs 27 and the upper part discharge channels 28 of the disc section upper part 15b is preferably designed to be "mirror-identical" to the contour of the base webs 16 and the lower part discharge channels 17 of the disc section lower part 15a, such that the engagement webs 27 of the disc section upper part 15b engage in the discharge channels 17 of the disc section lower part 15a and the base webs 16 of the disc section lower part 15a engage in the discharge channels 28 of the disc section upper part 15b - preferably with little play - and are displaceable there relative to one another.
[0062] If the disc section upper part 15b is now rotated relative to the disc section lower part 15a by the pitch of the respective webs 6, 27 and discharge channels 17, 28 (in this example four base webs 16, as well as four engagement webs 27 and four discharge channels 17, 28, which corresponds to a pitch of 36078 = 45°) - as shown in Fig. 3 and Fig. 4 - the base webs 16 of the disc section lower part 15a can be inserted or pushed into the upper part discharge channels 28 of the disc section upper part 15b and the engagement webs 27 of the disc section upper part 15b into the lower part discharge channels 17 of the disc section lower part 15a.
[0063] By means of a suitable drive (not shown here), the disc section upper part 15b can be raised or lowered relative to the disc section lower part 15a. This drive can be implemented, for example, electrically, hydraulically, or pneumatically and can also comprise suitable kinematics or a suitable adjustment mechanism. This allows the free cross-sectional area of the discharge channels 17, 28 to be continuously adjusted between a minimum and a maximum value. The raising or lowering of the disc section upper part 15b by the drive can take place both during operation—i.e., when the centrifuge drum 1 is rotating—and when the centrifuge drum 1 is at a standstill.
[0064] In this way, the distance A between the two disc section parts 15a, 15b of the peeling disc 14 and thus the free cross-sectional area of the lower part and upper part discharge channels 17, 28 can be changed, so that a peeling disc 14 is created whose conveying capacity can be continuously changed between a minimum value and a maximum value.
[0065] The respective discharge channel 23 has an opening 25 radially outward. This opening 25 serves to, and is arranged and dimensioned in such a way that, a flow of liquid phase from one of the lower section discharge channels 17 and one of the upper section discharge channels 28 into the respective discharge channels in the shaft section 18 is possible. If the upper section 15b of the disc section is moved all the way up, the opening 25 is maximally exposed. If the upper section 15b of the disc section is moved all the way down, only a smaller part of the opening 25 is exposed or it is even closed.
[0066] Thus, the liquid phase Lp can flow through the lower part discharge channels 17 of the disc section lower part 15a and the upper part discharge channels 28 of the disc section upper part 15b into the discharge channels 23 of the shaft section 18.
[0067] An opening 29 can be formed concentrically with the cover plate 26 of the disc section upper part 15b, said opening being aligned with the interior of a tubular collar 30 that can be integrally formed on the cover plate 26, so that the disc section upper part 15b can be pushed onto the shaft section 18 and is slidably guided thereon (see Fig. 3 and Fig. 4). The openings 25 to the drainage channels 23 in the shaft section 18 are designed such that the liquid phase Lp can flow through the discharge channels 17 of the disc section lower part 15a and through the discharge channels 28 of the disc section upper part 15b into the drainage channels 23 of the shaft section 18 (see also Fig. 3 and Fig. 4).It can be provided that the collar 30 covers the openings 25 in the shaft section 18 completely or partially radially outwards in the manner of a diaphragm when the disc section upper part 15b is displaced axially further downwards from its uppermost position (see also Fig. 3 and Fig. 4).
[0068] The maximum distance A or the adjustment path V of the two disc section parts 15a, 15b to each other can be limited by a suitable drive and / or adjustment mechanism so that the respective lower part discharge channels and upper part discharge channels 17, 28 and base webs and engagement webs 16, 27 always overlap axially.
[0069] The minimum vertical distance A between the two disc section parts 15a, 15b can be limited by a suitable drive and / or adjustment mechanism such that a defined open minimum cross-section of the discharge channels 17, 28 is still formed by the respective lower part discharge channels and upper part discharge channels 17, 28 and respective webs 16, 27.
[0070] In a further embodiment of the invention, the minimum vertical distance A between the two disc section parts 15a, 15b can be selected such that the respective lower part discharge channels and upper part discharge channels 17, 28 can be completely closed by the respective webs 16, 27.
[0071] As the disc section upper part 15b is lowered, the openings 25 in the drainage channels 23 of the shaft section 18 are increasingly covered in the axial direction. The collar 30 on the disc section upper part 15b prevents the openings 25 above the cover plate 26 of the disc section upper part 15b from being exposed again if the disc section upper part 15b is lowered further.
[0072] In a further embodiment (see Fig. 3 and Fig. 4), the upper disc section part 15b can be pressed against the lower disc section part 15a by a spring 31 until the minimum cross-section of the discharge channels 17, 28 is reached. By means of a suitable drive (not shown here), the upper disc section part 15b can be raised or lowered relative to the lower disc section part 15a against the spring force. This drive can be electrical, hydraulic or pneumatic, for example, and can also comprise suitable kinematics or a suitable adjustment mechanism. This allows the free cross-sectional area of the discharge channels 17, 28 to be continuously adjusted between a minimum and a maximum value. The raising or lowering of the upper disc section part 15b by the drive can take place both during operation - i.e. when the centrifuge drum 1 is rotating - and when the centrifuge drum 1 is at a standstill.
[0073] The target value for such an adjustment (adjustment path or adjustment force) can be specified manually by the centrifuge operator or result from the result of a control or regulation process of the centrifuge's control device. This control or regulation process is carried out with the aid of a control device (not shown here), which can be connected to the drive and one or more sensors. This can be advantageously used in such a way that, in a method for controlling or regulating the operation of the centrifuge with the paring disk shown in Fig. 4 and provided with a drive, an automated adjustment of a or the relative position between the disk section upper part and the disk section lower part 15b, 15a.
[0074] Since the sum of the pressure forces inside the peeling disc 14 is greater than outside, and since this pressure varies depending on the power, a self-adjusting system can be realized with appropriate dimensioning of the spring 31. As the internal pressure increases, the upper part of the disc section 15b can then be lifted against the spring 31 until the resulting force of the internal pressure corresponds to the force of the tensioned spring 31.
[0075] If the centrifuge is fed with a low feed rate [l / h] of the product P to be separated, it may also be useful to reduce the cross-section of the discharge channels of the paring disc 14, since otherwise an undesirable pulsating pumping of the paring disc 14 occurs or cavitation occurs, in particular at the inlet edges 32 of the respective webs 16, 27 of the respective disc section part 15a, 15b leading with respect to the direction of rotation DR of the liquid flow.
[0076] The discharge capacity of the peeling disc 14 can be adjusted manually, for example with the aid of a value table in which the suitable cross-section of the discharge channels 17, 28 or the vertical distance A of the two disc section parts 15a, 15b is listed depending on the inlet capacity of the product P.
[0077] The discharge performance of the impeller disc 14 can also be adjusted automatically in the sense of the control or regulation process mentioned above, for example, by sensing cavitation with a suitable sensor (not shown here) and then, with the aid of the control device and the correspondingly designed control or regulation program and the drive, changing the vertical distance A between the two disc section parts 15a, 15b so that cavitation no longer occurs. A defined adjustment of the vertical distance A between the disc section upper part 15b and the disc section lower part 15a during assembly is also conceivable, depending on the planned throughput of the respective centrifuge. In this way, impeller discs 14 can be easily realized for different operating points and discharge performances using identical components.
[0078] List of reference symbols
[0079] 1 centrifugal drum
[0080] 2 Drum base
[0081] 3 Drum top
[0082] 4 piston valves
[0083] 5 Drum interior
[0084] 6 stacks of plates
[0085] 7 separating plates
[0086] 8 Distribution shaft
[0087] 9 distributors
[0088] 10 Inlet pipe
[0089] 11 distribution channels
[0090] 12 Exit opening
[0091] 13 Peeling disc chamber
[0092] 14 Peeling disc
[0093] 15 disc section
[0094] 15a Disc section lower part
[0095] 15b Disc section upper part
[0096] 16 Base bridge
[0097] 17 Discharge channel
[0098] 18 Shaft section
[0099] 19 pipe
[0100] 20 pipe
[0101] 21 Annular space
[0102] 22 rib
[0103] 23 Drain channel
[0104] 24 Process
[0105] 25 Opening
[0106] 26 Cover plate
[0107] 27 Intervention bridge
[0108] 28 discharge channel
[0109] 29 Opening
[0110] 30 collars
[0111] 31 spring
[0112] 32 Leading edge
[0113] 33 hood
[0114] 34 solids traps
[0115] 35 drive spindle
[0116] 36 Fluid drain
[0117] 37 Base plate A distance
[0118] D axis of rotation
[0119] DR direction of rotation
[0120] D1 first diameter D2 second diameter
[0121] P Product
[0122] Lp liquid phase
[0123] Sp solid phase
[0124] H1 , H2 height M center line
[0125] V adjustment range
Claims
Claims 1. A centrifuge for centrifugal separation, 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, the centrifuge comprising at least the following: a) a rotatable centrifugal drum (1) with a rotational axis D, b) at least one paring disc (14) which is intended to discharge the at least one liquid phase Lp from the rotating centrifuge drum (1) during operation, c) the paring disc (14) comprising a cylindrical disc section (15) with a first, larger diameter D1 and a cylindrical shaft section (18) with a second, smaller diameter D2, d) the disc section (15) of the paring disc (14) comprising at least one or more discharge channels (17, 28),e) wherein at least the disc section (15) of the peeling disc (14) is divided and has a disc section lower part (15a) and a disc section upper part (15b), and f) wherein the disc section upper part (15b) is movable relative to the disc section lower part (15a), characterized in that g) the disc section upper part (15b) is axially movable relative to the disc section lower part (15a), 2. Centrifuge according to claim 1, characterized in that the disc section upper part (15b) can be axially raised or lowered relative to the disc section lower part (15a).
3. Centrifuge according to claim 1 or 2, characterized in that the disc section upper part (15b) is movable by a drive relative to the disc section lower part (15a), in particular axially raising or lowering.
4. Centrifuge according to one of the preceding claims, characterized in that the centrifuge is designed as a separator whose centrifugal drum rotates during operation about a vertical axis of rotation D in a direction of rotation DR.
5. Centrifuge according to one of the preceding claims, characterized in that the paring disc (15) is designed as an element which is not rotatable during operation or is rotatable at a differential speed to the centrifugal drum.
6. Centrifuge according to one of the preceding claims, characterized in that the drive is electrical, hydraulic or pneumatic.
7. Centrifuge according to one of the preceding claims, characterized in that a cross section of the discharge channels (17, 28) is adjustable by the drive during operation and / or when the centrifugal drum (1) is at a standstill.
8. Centrifuge according to one of the preceding claims, characterized in that the cross-section of the discharge channels (17, 28) is continuously adjustable by the drive.
9. Centrifuge according to one of the preceding claims, characterized in that the discharge channels (17, 28) comprise lower part discharge channels (17) and upper part discharge channels (28) and that by a relative displacement of the disc section upper part (15b) relative to the disc section lower part (15a) both the cross section of the lower part discharge channels (17) and the cross section of the upper part discharge channels (28) can be changed.
10. Centrifuge according to one of the preceding claims, characterized in that the disc section lower part (15a) has the paring disc shaft (18).
11. Centrifuge according to one of the preceding claims, characterized in that the disc section lower part (15a) has a base plate (37) and a plurality of crescent-shaped base webs (16) arranged thereon, which extend in an arcuate manner radially from the inside to the outside and which have a height H1 in the axial direction, wherein the lower part discharge channels (17) are formed in the circumferential direction between the base webs (16), which extend correspondingly in an arcuate manner radially from the inside to the outside and which are each delimited downwards by the base plate (37) and upwards by the disc section upper part (15b).
12. Centrifuge according to one of the preceding claims, characterized in that the disc section upper part (15b) has a cover plate (26), below which a number of engagement webs (27) corresponding to the number of lower part discharge channels (17) is formed, which extend arcuately radially from the inside to the outside and which have a height H2 in the axial direction, wherein between the engagement webs (27) the upper part discharge channels (28) which extend radially from the inside to the outside in a correspondingly arcuate manner and which are each delimited at the top by the cover plate (26) and at the bottom by the disc section lower part (15a).
13. Centrifuge according to one of the preceding claims, characterized in that the heights H1 and H2 are different or equal.
14. Centrifuge according to one of the preceding claims, characterized in that the contour of the engagement webs (27) and the upper part discharge channels (28) of the disc section upper part (15b) is designed to be mirror-identical to the contour of the base webs (16) and the lower part discharge channels (17) of the disc section lower part (15a), so that the engagement webs (27) of the disc section upper part (15b) engage in the lower part discharge channels (17) and the base webs (16) of the disc section lower part (15a) engage in the upper part discharge channels (28) and are displaceable there, which changes the cross section of the lower part discharge channels (17) and the cross section of the upper part discharge channels (28).
15. Centrifuge according to one of the preceding claims, characterized in that the base webs (16) of the lower disc section part (15a) can be inserted in a form-fitting manner into the discharge channels (28) of the upper disc section part (15b) and the engagement webs (27) of the upper disc section part (15b) can be inserted in a form-fitting manner into the discharge channels (17) of the lower disc section part (15a).
16. Centrifuge according to one of the preceding claims, characterized in that the cover plate (26) has a central opening (29) and an annular tubular collar (30) adjoining the side of the cover plate (26) facing away from the engagement webs (27) of the disc section upper part (15b), which is designed such that the disc section upper part (15b) with the collar (30) is guided displaceably radially outwardly on the shaft section (18) of the disc section lower part.
17. Centrifuge according to one of the preceding claims, characterized in that the shaft section (18) is longer than the collar (30).
18. Centrifuge according to one of the preceding claims, characterized in that the shaft section (18) has, at the axial height of the lower part and upper part discharge channels (17, 28), a plurality of circumferentially distributed openings which are aligned with the lower part discharge channels (17) and the upper part discharge channels (28), in particular when the disc section upper part (15b) is displaced from a lower position to an upper position, so that the liquid phase is passed through the Lower part discharge channels (17) and the upper part discharge channels (28) can flow into one or more discharge channels (23) of the shaft section (18).
19. Centrifuge according to one of the preceding claims, characterized in that the annular collar (30) completely or partially covers the openings (25) in the shaft section (18) when the disc section upper part (15b) is displaced into an axially lower position.
20. Centrifuge according to one of the preceding claims, characterized in that a maximum distance A between the two disc section parts (15a, 15b) can be limited by the drive and / or the adjusting mechanism such that the respective discharge channels (17, 28) and respective webs (16, 27) always overlap axially.
21. Centrifuge according to one of the preceding claims, characterized in that the minimum vertical distance A between the two disc section parts (15a, 15b) can be limited by the drive and / or the adjusting mechanism such that a defined open minimum cross-section of the discharge channels (17, 28) is formed by the respective discharge channels (17, 28) and respective webs (16, 27).
22. Centrifuge according to one of the preceding claims, characterized in that the minimum vertical distance A between the two disc section parts (15a, 15b) can be selected such that the respective discharge channels (17, 28) are completely closed by the respective webs (16, 27).
23. Centrifuge according to one of the preceding claims, characterized in that the collar (30) on the disc section upper part (15b) prevents the openings (25) above the cover plate (26) of the disc section upper part (15b) from being opened again when the disc section upper part (15b) is lowered even further.
24. Centrifuge according to one of the preceding claims, characterized in that the disc section upper part (15b) is pressed against the disc section lower part (15a) by a spring (31) until a minimum cross-section of the discharge channels (17, 28) is reached.
25. Centrifuge according to one of the preceding claims, characterized in that the drive causes the disc section upper part (15b) to be moved relative to the The lower part of the disc section (15a) is adjustable against the spring force, ie can be raised or lowered.
26. Method for controlling or regulating the operation of a centrifuge according to one or more of the preceding claims, characterized in that the Method comprising an automated adjustment of the relative position between the disc section upper part (15b) and the disc section lower part (15a).
27. Method according to claim 26, characterized in that during the automated adjustment of the relative position between the disc section upper part (15b) and the lower part of the disc section (15a), the spring force of the spring (31) or the adjustment path of the upper part of the disc section is used as a control or reference variable.