Solid bowl centrifuge and method for exchanging the distributor of the solid bowl centrifuge

Abstract

The invention relates to a solid bowl screw centrifuge which is used for clarifying a flowable suspension (S) in a centrifugal field into a solid phase (SP) and one or more liquid phases (FP) and which comprises at least: a bowl (2) which is mounted for rotation about an axis of rotation (D); and a scroll (3) which is arranged in the bowl (2), is mounted for rotation about the axis of rotation and has a scroll hub (308) and a scroll flight (309) projecting radially from the scroll hub, wherein: a rotatable or non-rotatable feed pipe (5) is provided for feeding the suspension into a distributor (6) which can be rotated together with the scroll (3); the distributor (6) is used to divert the suspension from the axial direction into the radial direction and, during operation, to accelerate the suspension in the circumferential direction and to direct the suspension into a separating space (TR) between the scroll (3) rotating during operation and the bowl (2) rotating during operation; the distributor (6) is inserted into the scroll (3) and has a radial channel for distributing the flow of the suspension to be fed; the distributor (6) is designed as an exchangeable tubular distributor sleeve (61) which, for installation, can be inserted radially into a radial opening (310) in the scroll and, for removal, can be radially taken back out of the radial opening (310).

Description

[0001] Solid-wall screw centrifuge and method for changing the distributor of the solid-wall screw centrifuge

[0002] The present invention relates to a solid-jacket screw centrifuge according to the preamble of claim 1 and a method for changing a distributor of a solid-jacket screw centrifuge.

[0003] Solid-wall screw centrifuges – hereinafter also referred to synonymously as decanters – are known in various embodiments from the prior art. They serve to clarify and, if necessary, separate a free-flowing suspension in a centrifugal field into a discharged solid phase (which in this application also includes a barely free-flowing sludge phase) and into one or more liquid phases.

[0004] The rotor of a decanter consists of a solid drum with a cylindrical and usually conical section, and a screw body mounted inside it. Both rotate at high speed, with the screw having a differential speed compared to the drum.

[0005] The suspension to be separated flows centrally through an inlet pipe and enters the cylindrical part of the drum, the actual separation chamber, via a distributor through the screw base. There, due to the prevailing centrifugal field, a circular cylindrical liquid chamber forms, which is called the pond.

[0006] Due to the density difference between the denser solid and the less dense liquid, the solid settles onto the inner wall of the drum and is conveyed by the screw to a solids outlet in the conical section of the drum, where it is discharged. Above this, the clarified liquid phase flows in the opposite direction towards an axial drum lid, which has an outlet through which it is discharged (at an overflow weir, in a skimming disc, or similar device).

[0007] The distributor is to be optimized. The suspension to be supplied to the decanter is fed into the decanter through the inlet pipe. According to the design discussed in this document, the suspension is first transferred from the inlet pipe into a rotating distributor – usually rotating with a screw conveyor (an exemplary embodiment according to the prior art is shown in Fig. 8).

[0008] In the distributor, the incoming suspension from the axial feed pipe is deflected and flows radially into the separation chamber. During this deflection, the distributor is subject to increased wear, especially with suspensions containing abrasive components, so that replacement of the distributor may be necessary.

[0009] From DE 199 52 804 A1, a solid-bowl screw centrifuge is known in which the distributor forms an integral part of the screw body, as it is welded into it. The problem is that, when wear occurs, a considerable effort is required to replace the distributor welded into the screw body.

[0010] From generic German patent DE 1 817 573 A1, a solid-jacketed screw centrifuge is also known, in which a distributor insert with a multi-part distributor sleeve can be axially removed from the hollow shaft or screw hub after its disassembly. However, to enable access to the hollow shaft, the screw must be disassembled in a complex process, including the removal of the screw bearings, which is also very time-consuming.

[0011] EP 1 483 055 B1 describes a solid-wall screw centrifuge with an inlet chamber (distributor) whose outlet openings are fitted with reinforcement elements. These reinforcement elements can be installed into the inlet chamber from the outside of the screw hub for replacement.

[0012] Finally, DE 10 2021 106 496 A1 describes a distributor made of a wear-resistant material. The distributor itself is relatively easy to install, but it must be inserted axially into the screw hub, meaning that the screw bearing and the feed pipe must first be removed for replacement.

[0013] Against this background, the object of the invention is to further develop the generic solid-bowl screw centrifuge in such a way that the distributor can be replaced more easily in the event of wear than according to the prior art. The invention achieves this object through the subject matter of claim 1 and the method of claim 20.

[0014] According to claim 1, a solid-wall screw centrifuge is created, which serves to clarify a free-flowing suspension in a centrifugal field into a solid phase and into one or more liquid phases and comprises at least: a drum rotatably mounted about an axis of rotation and a screw arranged in the drum rotatably mounted about the axis of rotation, the screw having a screw hub and a screw turn projecting radially from the hub, wherein a rotatable or non-rotatable feed pipe is provided for directing the suspension into a distributor rotatable together with the screw, wherein the distributor serves to redirect the suspension from the axial direction into the radial direction and, during operation, to accelerate it circumferentially and direct it into a separation chamber between the screw rotating during operation and the drum rotating during operation.wherein the distributor is inserted into the screw and has a radial channel for flow division of the suspension to be supplied, and wherein the distributor is designed as an interchangeable tubular distributor sleeve which can be inserted radially into a radial opening in the screw for assembly and can be removed radially from the radial opening for disassembly.

[0015] This design allows for easy replacement of the distributor in case of wear, as it eliminates the need to disassemble the worm bearing or the worm itself. This simplifies maintenance and repairs, and also results in cost-effective manufacturing. This is particularly true if the distributor sleeve is a single piece, as it can then be easily replaced as a whole by radially removing and reinserting it. A single-piece distributor sleeve is defined as one that does not have any sleeve sections axially attached to a central distributor sleeve segment, as is known from DE 1 817 573 A.

[0016] In a preferred embodiment, the screw may have a cylindrical section, and the opening is formed in this cylindrical section, passing through the screw hub and, if necessary, the screw thread. The opening is optimally positioned in this area. Since it completely passes through the screw hub and, if necessary, the screw thread, a further advantageous feature is realized, enabling purely radial installation and removal of the distributor sleeve. This also allows for a high degree of standardization with regard to the distributor.

[0017] In a further advantageous embodiment, the opening and the distributor sleeve can have the same radial extent at one or both of their radial ends. Alternatively, the distributor sleeve can project radially from the opening into the separation chamber at one or, preferably, both ends. A person skilled in the art can determine the optimal configuration by testing with the suspension to achieve optimal separation.

[0018] In another advantageous embodiment, the opening and the distributor sleeve may have geometrically corresponding internal and external geometries at one or both of their radial ends, so that the distributor sleeve is advantageously held axially in the opening in its installed state. It may then be preferably provided that one or more fixing means are provided for radially fixing the distributor sleeve in the screw. According to a preferred embodiment, these may comprise one or more screw bolts. In this way, radial fixing of the distributor sleeve is also achieved in a simple manner, so that it is securely held both axially and radially.

[0019] According to a particularly preferred optional embodiment, it can be provided that the screw bolt(s) are designed in such a way that they can be mounted radially from the inside to the outside through wall bores of the distributor sleeve, which may be provided with internal threads, from the inside to the outside.

[0020] This type of radial fixing of the distributor sleeve eliminates the need to dismantle parts of the screw to gain access to screw bolts inside the screw hub, as was provided, for example, in generic DE 1 817 573 A1.

[0021] In a further particularly preferred optional embodiment, the screw bolt(s) can project axially outwards into the interior of the hollow shaft-like screw body with a bolt section, preferably such that the bolt section(s) prevent radial movement of the distributor sleeve. In this way, the distributor sleeve is fixed radially in the screw hub particularly easily and securely. Furthermore, the extension of the distributor in the radial direction (immersion) allows for a gentle flow of the suspension into the separation chamber.

[0022] In order to meet even high sanitary requirements, the end faces on the distributor sleeve can preferably be machined without notches so that they adapt to the contour of the screw hub essentially seamlessly.

[0023] According to a further optional preferred embodiment, the distributor sleeve may have a lateral opening in the axial direction of the inlet pipe that penetrates its circumferential wall, through which the product or the suspension to be processed is guided axially from the inlet pipe into the distributor sleeve.

[0024] According to a further optional preferred embodiment, if the inlet pipe is designed as a stationary inlet pipe (not rotating during operation), it may end shortly before the opening or protrude slightly into the distributor sleeve. According to a further optional preferred embodiment, if the inlet pipe is designed as a rotating inlet pipe during operation, it may be connected to the distributor sleeve via a detachable connection. And according to a further optional preferred embodiment, which facilitates changing the distributor sleeve, the inlet pipe may be axially withdrawn from the opening of the distributor sleeve.

[0025] According to the invention, a wide variety of flow-optimized geometries can be realized depending on the suspension and the requirements of the separation process.

[0026] According to a further optional preferred embodiment, a deflection device can be provided inside the distributor sleeve, designed to deflect axially impinging liquid flow at least in one or two radial directions and preferably in a further direction. This deflection is advantageously gentler than without such a device.

[0027] In a further optional preferred embodiment, the deflection device can be conical, wedge-shaped, and / or helical. Depending on the geometry, the deflection of the suspension during the feed into the separation chamber TR is optimized. Alternatively or optionally, in another preferred embodiment, the deflection device can project from the inner wall of the distributor sleeve into it, preferably from the area opposite the opening towards the feed pipe. And / or, in a further preferred embodiment, the cross-section of the distributor sleeve can be substantially circular, elliptical, oblong, or rectangular. All of these are advantageous options for realizing efficient, easily replaceable, and space-saving distributors.

[0028] The distributor sleeve can be sealed against the wall of the screw hub by one or more surrounding seals.

[0029] According to claim 21, an advantageous method for changing a distributor sleeve in a solid-jacket screw centrifuge according to one of the related claims is further provided, comprising at least the following steps:

[0030] - the screw is pulled out of the drum and then the distributor sleeve is preferably detached from the screw without disassembling any elements of the screw and pulled radially out of it,

[0031] - the new distributor sleeve is then inserted radially back into the screw and secured there, and

[0032] - then the snail is pushed back into the drum.

[0033] Further advantageous features can be found in the remaining dependent claims and the preferred embodiments.

[0034] The invention is described in more detail below with reference to exemplary embodiments and the figures. However, the figures are to be understood as merely illustrative and do not represent the invention exhaustively. Other embodiments and equivalents of the depicted configurations are also feasible and fall within the scope of protection. Furthermore, individual features described in clauses, sentences, or paragraphs of the following description are, when considered individually, not only advantageous for the respective illustrated embodiment but can also be used more generally for other embodiments of the invention, which then incorporate these features. The figures show:

[0035] Figure 1a: a schematic sectional view of an embodiment of a solid-wall screw centrifuge according to the invention; Figure 1b: a schematic sectional view of another embodiment of a solid-wall screw centrifuge according to the invention;

[0036] Figure 2: a close-up of a section of the solid-jacket screw centrifuge encompassing the distributor from Fig. 1;

[0037] Figure 3: an example of a more detailed constructive design of the distributor area of ​​a solid-jacket screw centrifuge according to Fig. 1a and 2;

[0038] Figure 4: in a) to d) schematic representations of deflection devices in a distributor sleeve;

[0039] Figure 5: various other schematic representations of deflection devices in a distributor sleeve;

[0040] Figure 6: in a) to c) various distributor sleeves, in which the circumferential wall has been partially hidden in the upper part towards the front;

[0041] Figure 7: in a) to c) cross-sectional views of various schematically represented distributor sleeves;

[0042] Figure 8: a schematic sectional view of a well-known solid-metal screw centrifuge;

[0043] Fig. 8 shows a solid-jacket screw centrifuge. This has a machine frame 1 and a rotor with a rotating drum 2 and a rotating screw 3.

[0044] The drum 1 is rotatably mounted in the machine frame 100 by means of one or more bearings – here two drum bearings – 201, 202 about an axis of rotation D. Typically, with a horizontal orientation of the axis of rotation, as shown in the example, two drum bearings are provided, while with a vertical orientation of the axis of rotation, only a single drum bearing may be provided. The screw 3 is further rotatably mounted relative to the drum 2 about the axis of rotation D by means of one or more – here two – screw bearings 301, 302, wherein these screw bearings 301, 302 are arranged at the two ends of the drum 2 and the screw 3 between sleeve-shaped projections 203, 204, 303, 304 of the drum 2 and the screw 3.

[0045] A drive device 4 with a motor 401 - preferably an electric motor - which is coupled here by way of example via two wrap gears 402, 403 to a gearbox 404, which in turn is coupled to the drum 2 and the worm 3, serves to rotate the drum 2 and the worm 3 in operation.

[0046] Radial directions perpendicular to the axis of rotation D are designated with "R" and axial directions parallel to the axis of rotation D with "A".

[0047] The drum 2 and the screw 3 can each have a substantially cylindrical section 205, 305 and can optionally preferably each have only a conically tapered section 206, 306. The solid-bowl screw centrifuge 1 serves to clarify and separate a free-flowing suspension S in a centrifugal field into a solid phase SP and into one or more – here one – liquid phase(s) FP.

[0048] The snail 3 also has a hollow wave-shaped snail body (also called snail hub) 308 and a snail turning egg 309.

[0049] The drum 2 can further have a drum cover 207 at its cylindrical end. This drum cover 207 can preferably be detachably attached to the rest of the drum 2, for example by means of screw bolts or the like (not shown here).

[0050] With appropriate control of the drive device by an associated control unit (not shown here), the screw 3 can rotate at a slightly lower or higher speed than the drum 2 during operation of the solid-walled screw centrifuge 1, so that a differential rotational speed can occur between the screw 3 and the drum 2. An axially extending, central feed pipe 5 serves to feed the material to be centrifuged axially into a distributor 6 that is rotatably connected to the screw 3. The feed pipe 5 can be rotatably connected to the screw 3. However, it can also be designed as a stationary feed pipe 5 that does not rotate during operation.

[0051] The distributor 6, on the other hand, forms part of the rotor, which here rotates at the speed of the screw. It serves to redirect the suspension S exiting the feed pipe 5 in two opposite radial directions: radially outwards and to introduce it into the separation chamber T between drum 2 and screw 3, and to accelerate the product in the circumferential direction of rotation to the speed of the screw 3. The distributor 6 is described in more detail below.

[0052] In the separation chamber TR, a circular cylindrical liquid space forms due to the rotation of the drum 2 in the centrifugal field, the so-called "pond" (not shown here).

[0053] The depth of the pond in drum 2 is limited by a liquid discharge, which is implemented here by a weir 208. Due to the density difference between the denser solid phase SP and the less dense liquid phase FP, the solid phase SP settles on the inner wall of drum 2. Radially further inwards, the clarifying suspension liquid, or the liquid phase FP, flows into the screw conveyor 309 towards the weir 208.

[0054] In the opposite direction to the liquid flow, the solid phase SP is conveyed by the differential movement of the screw 3 resulting from its greater or lesser speed relative to the drum 2. This movement is initially directed along the cylindrical section 205 of the drum 2 and subsequently up the conical section 206 of the drum 2. The screw reversing mechanism 309 serves this purpose. The solid phase SP then leaves the liquid reservoir, is transported over the "dry" part of the conical section 206 of the drum 2, and is subsequently discharged through a solids outlet 210.

[0055] The liquid phase FP, on the other hand, flows towards the larger drum diameter at the opposite end of drum 2 and is discharged there by the weir 208 – located here in the drum cover 207. This is a two-phase separation, in which a suspension to be clarified is separated into a single solid phase SP and a single liquid phase FP. Alternatively, the solid-bowl screw centrifuge can also be designed so that the suspension to be clarified S is separated into a single solid phase SP and two liquid phases FP1 and FP2.

[0056] As far as described so far, the embodiment of the solid-wall screw centrifuge according to the invention shown in Fig. 1a corresponds to that of the prior art shown in Fig. 8. A significant difference lies in the design of the distributor 6 of the solid-wall screw centrifuges according to the invention.

[0057] This will be explained in more detail below, first with reference to Figures 1a and 2 to 3.

[0058] In Figs. 2 and 3, the distributor s is shown enlarged, with Fig. 3 revealing further design details and options.

[0059] The distributor 6 is designed to pre-accelerate the suspension or product to the screw speed, thereby reducing turbulence in the separation chamber. To achieve this, it deflects the suspension from the axial flow direction (inlet pipe 5) into two opposing radial directions through the distributor 6 into the separation chamber TR.

[0060] The outflow from distributor 6 and the inflow into separation chamber TR should occur with the lowest possible shear, so that – if a flocculant is added – segregation between the flocculant added to the suspension and the suspension itself is largely avoided. The flocculant should bind with the solid phase in the suspension so that it can be separated more effectively in the separation chamber of the solid-bowl screw centrifuge. Furthermore, the flow conditions in distributor 6 should be as laminar as possible.

[0061] Easy assembly and disassembly of distributor 6 are desirable in case of replacement, as distributor 6 is subject to wear during operation, particularly due to the influence of abrasive particles in the suspension (depending on its composition). Removal of distributor 6 is always necessary when excessive wear is present and / or when sealing elements need to be replaced. It may also be necessary for other reasons, such as when a replacement with a different version or revision is required.

[0062] According to the state of the art shown in Fig. 8, such removal and possible replacement of the distributor 6 is complicated, since to change the distributor 2 not only does the screw 3 and the inlet pipe 5 have to be pulled out of the drum 3, but the screw 3 itself also has to be disassembled in a cumbersome manner in order to be able to change the distributor 6.

[0063] This is different after the invention.

[0064] Here, to change the distributor 6, the screw 3 is indeed pulled out of the drum 2. The inlet pipe 5 is also moved axially or pulled out of the screw 3. However, the distributor 6 is installed in the screw 3 in such a way that it is possible to remove it radially without disassembling the screw 3, and to replace it with another distributor 6. Alternatively, this "other" distributor 6 can, of course, also be the existing distributor 6 – possibly refurbished.

[0065] It is advantageously provided that the distributor 6 is designed as a tubular element, which is referred to as the distributor sleeve 61. This distributor sleeve 61 can be formed in one piece.

[0066] The screw 3 then has a corresponding radial opening 310 shaped to correspond to the distributor sleeve 61, into which the distributor sleeve 61 is inserted.

[0067] The opening 310 – for example, a through-bore radial to the axis of rotation through the screw 3 in the cylindrical area of ​​the screw hub 308 – and the distributor sleeve 61 are designed and matched such that the distributor sleeve 61 can be inserted radially into the opening 310 during installation and removed radially from the opening 310 during removal. For this purpose, the opening 310 extends radially through the screw hub 308. The feed pipe 5 is preferably located approximately centrally with respect to this opening. Optionally, the distributor sleeve 61 can also extend through the screw turn 309 (which then has corresponding recesses so that the distributor sleeve 61 can be inserted and removed radially once the screw 3 has been pulled out of the drum 2).

[0068] To fix the distributor sleeve 61 radially in the worm 3, one or more fixing means can be provided. These fixing means can, in a simple embodiment, be designed as one or more, here two, screw bolts 62. The screw bolt(s) 62 can advantageously be designed such that they can be mounted from the interior of the distributor sleeve through wall bores 611 in the distributor sleeve 61, which may optionally be provided with internal threads, radially with respect to the axis of the distributor sleeve or axially with respect to the axis of rotation, from the inside out.In a simple embodiment, they then project axially outwards into the interior of the hollow shaft-like screw body 308 with a bolt section 621 with respect to the axis of rotation D and are positively engaged against the inner wall of the hollow shaft-like screw body at opposite points, preferably in such a way that the bolt section(s) 621 reliably prevent radial movements of the distributor sleeve 61 during operation.

[0069] The distributor sleeve 61 is thus held radially and axially in the screw 3 by a positive fit and can be removed from the drum 2 after the screw 3 has been removed, without the need to disassemble the screw 3. The distributor 6 can therefore be removed from the screw 3 without having to disassemble the screw 3 itself beforehand, and also without having to disassemble the screw bearing. While the feed pipe 5 may need to be moved axially, this is usually easily accomplished.

[0070] This makes it easy to maintain and repair, and also results in cost-effective manufacturing.

[0071] The distributor sleeve penetrates the bore 310 radially completely or almost completely in one or both radial directions (Figs. 1a, 2, 3). It can also project outwards from the opening 308 in one or both radial directions beyond the outer circumference of the screw hub 308 in this area (Fig. 1b). There are two radial outlets at opposite ends of the distributor sleeve 61, pointing in opposite radial directions into the separation chamber TR.

[0072] According to Fig. 1a, in this embodiment the length of the distributor sleeve 61 corresponds to the diameter of the worm hub 308 in this area, so that in the assembled state it preferably does not protrude from the worm hub 308 at its two radial ends.

[0073] The end faces (in Fig. 1a and 2 the upper and lower radial ends) of the distributor sleeve 61 can be machined so that they conform seamlessly to the contour of the worm hub 308 essentially at one or both radial ends (see, for example, the abstracted Fig. 2).

[0074] For certain applications, an alternative design may be advantageous in which the distributor sleeve 61 protrudes from the hub at one or both radial ends and extends into the separation space (see Fig. 1 b).

[0075] In the axial direction of the inlet pipe 5, the distributor sleeve 61 has a lateral opening 613 (see Fig. 3, e.g., a bore) with a diameter D1 (see Fig. 7a-c) extending through its circumferential wall, through which the product or the suspension to be processed is guided axially from the inlet pipe 5 into the distributor sleeve 61. This opening 613 is preferably located approximately centrally with respect to the radial extent of the distributor sleeve 61, so that the inflowing suspension is deflected in two opposite radial directions and can exit the distributor sleeve.

[0076] In the case of a stationary inlet pipe 5 – i.e., one that does not rotate during operation – it can end shortly before the opening 613 or it can project slightly into the distributor sleeve. Preferably, the design is such that the inlet pipe 5 can be pulled axially out of the distributor sleeve 61 and pushed back into it. For this purpose, a cylindrical extension projecting axially (with respect to the axis of rotation or radially with respect to the axis of the distributor sleeve) into the distributor sleeve can be provided as a circumferential boundary of the opening 613, into which the preferably axially movable inlet pipe 5 can be inserted. The inlet pipe 5 can preferably be displaceable axially with respect to the axis of rotation within the screw 3. In this respect, the inlet pipe 5 is a separate element from the screw 3.

[0077] In the case of a rotating inlet pipe 5, however, this can be connected to the distributor sleeve 61 via a detachable connection (see the schematic, simplified representation of Fig. 2).

[0078] To ensure a smooth transition from the axial flow direction of the inlet pipe to a radial flow direction in the distributor sleeve 61, a deflection device 614 may be provided inside the distributor sleeve. This device may be designed to deflect the fluid flow acting axially upon it into the preferably two radial directions (in the image "upwards and downwards").

[0079] For this purpose, it is advantageous if this deflection device 614 projects from the inner wall of the distributor sleeve 61 towards the inlet pipe 5, preferably from the area opposite the opening 613 (see Fig. 2 or 3).

[0080] This deflection device 614 can be designed in various ways.

[0081] The contour of the deflection device 614 can be designed differently.

[0082] The deflection device 614 can be designed, for example, in a conical shape (see the schematic representation in Fig. 4d) or a wedge shape (see the schematic representation in Fig. 4a) and project from the inner wall of the distributor sleeve 61, in particular from the area opposite the opening 613 (see Fig. 2 or 3).

[0083] The deflection device 614 can also be designed in the form of a twisted wedge (Figs. 4b, 4c, 6a; differences include left-hand twist, right-hand twist) to improve the product flow from the supply line into the distributor. Possible resulting deflection edges 6141 in the axially highest region of the deflection devices 614 are shown in Figs. 4a-c. The extension (see Fig. 5) of the deflection device 614 from the surrounding inner wall of the distributor sleeve towards the supply pipe 5 can be selected differently.

[0084] It should be emphasized once again that the deflection device 614 is an advantageous option. Fig. 6c, in contrast, illustrates an embodiment without such a deflection device, which projects from the inner wall of the distributor sleeve 61.

[0085] The cross-sectional shape of the distributor sleeve 61 can also be chosen almost arbitrarily. It can be optimized, if necessary, through testing with the suspension to be processed. The cross-sectional shape of the distributor sleeve 61 can, for example, be circular, oblong, elliptical, or polygonal, such as rectangular (see Fig. 7a, b, c).

[0086] The distributor sleeve 61 can be sealed against the wall of the worm hub 308 by one or more surrounding sealing rings 63.

[0087] The cross-section of the distributor sleeve 61 can, moreover, be essentially constant over its radial extent relative to the axis of rotation D (apart from the deflecting device and the area of ​​the opening 613). However, it can also vary.

[0088] The deflection device 614 deflects the suspension S in two radial directions and directs it into the separation chamber TR. If a portion of the suspension S attempts to flow back towards the inlet pipe 5, this portion can optionally be deflected back at the (distributor inlet) opening 613 by a suitable deflection contour 6131 (see Figure 7a-c). Figure 7a-c also clearly shows that the distributor cross-section can be rectangular, round, or oval, although it is not limited to these cross-sectional contours.

[0089] To mount the distributor sleeve 61, it is inserted radially into the bore 310 of the worm hub 308 and screwed into place from the inside of the distributor sleeve 61. Various arrangements for the screw bolts 62 are possible, which can secure the distributor sleeve 61 either on the outer surface of the hub or on the inside of the distributor. It should also be noted that the distributor sleeves 61 can be manufactured in a variety of ways; for example, complex outlet contours can be produced using the casting process. Wear protection can also be integrated as an option.

[0090] Reference sign

[0091] Machine frame 1

[0092] Drum 2

[0093] Drum bearings 201, 202

[0094] Approaches 203, 204

[0095] Sections 205, 206

[0096] Drum cover 207

[0097] Wehr 208

[0098] Solid waste outlet 210

[0099] Snail 3

[0100] Worm bearings 301, 302

[0101] Approaches 303, 304

[0102] Sections 305, 306

[0103] Snail hub 308

[0104] Snail turn egg 309

[0105] Breakthrough 310

[0106] Drive device 4

[0107] Engine 401

[0108] Wrap-around gear 402, 403

[0109] Gearbox 404

[0110] Inlet pipe 5

[0111] Distributor 6

[0112] Distributor sleeve 61

[0113] Wall drilling 611

[0114] Opening 613

[0115] Contour 6131

[0116] Deflection device 614

[0117] Deflection edge 6141

[0118] Screw bolt 62 Bolt section 621

[0119] Sealing ring 63

[0120] Axis of rotation D Axial direction A

[0121] Radial direction R

[0122] Suspension S

[0123] Solid phase SP

[0124] Liquid phase FP separation chamber TR

[0125] Diameter D1

Claims

Claims 1. A solid-wall screw centrifuge for clarifying a free-flowing suspension S in a centrifugal field into a solid phase (SP) and into one or more liquid phases (FP), comprising at least: a) a drum (2) rotatably mounted about an axis of rotation (D), and b) a screw (3) arranged in the drum (2) rotatably mounted about the axis of rotation, with a screw hub (308) and a screw turn (309) projecting radially from it, c) wherein a rotatable or non-rotatable feed pipe (5) is provided for supplying the suspension to a distributor (6) rotatable together with the screw (3), wherein the distributor (6) serves to redirect the suspension from the axial direction into the radial direction and, during operation, to accelerate it circumferentially and to direct it into a separation chamber (TR) between the screw (3) rotating during operation and the drum (2) rotating during operation.d) wherein the distributor (6) is inserted into the screw (3) and has a radial channel for dividing the flow of the suspension to be supplied, characterized in that e) the distributor (6) is designed as an interchangeable tubular distributor sleeve (61) which can be inserted radially into a radial opening (310) in the screw for assembly and can be removed radially from the radial opening (310) for disassembly.

2. Solid jacket screw centrifuge (1 ) according to claim 1 , characterized in that the distributor sleeve (61 ) is formed in one piece.

3. Solid-jacket screw centrifuge (1) according to claim 1, characterized in that the screw (3) has a cylindrical section (305) and that the opening (310) is formed in the cylindrical section, passing through the preferably hollow shaft-shaped screw hub (308) and optionally the screw turn (309).

4. Solid-jacket screw centrifuge (1) according to one of the preceding claims, characterized in that the opening (310) and the distributor sleeve (61) have geometrically corresponding features at one or both of their radial ends. have internal and external geometry such that the distributor sleeve (61) is axially positively locked in the opening (310) in its installed state.

5. Solid jacket screw centrifuge (1 ) according to one of the preceding claims, characterized in that the opening (310) and the distributor sleeve (61 ) have the same radial extent at one or both of their radial ends.

6. Solid jacket screw centrifuge (1 ) according to one of the preceding claims, characterized in that the distributor sleeve (61 ) projects radially from the opening into the separation chamber (TR) at one or both ends.

7. Solid-jacket screw centrifuge (1 ) according to one of the preceding claims, characterized in that one or more fixing means are provided for radial fixation of the distributor sleeve (61 ) in the screw (3).

8. Solid-jacket screw centrifuge (1 ) according to one of the preceding claims, characterized in that the fixing means comprise one or more screw bolts (62).

9. Solid-jacket screw centrifuge (1 ) according to one of the preceding claims, characterized in that the screw bolt(s) (62) are designed such that they can be mounted from the interior of the distributor sleeve (61 ) through wall bores (611 ) of the distributor sleeve (61 ) which may be provided with internal threads, penetrating the wall of the distributor sleeve (61 ) from the inside to the outside.

10. Solid-jacket screw centrifuge (1 ) according to one of the preceding claims, characterized in that the screw bolt(s) (62) with a bolt section (621 ) project axially outwards into the interior of the screw body (308) with respect to the axis of rotation D and are positively engaged with it, preferably in such a way that the bolt section(s) (621 ) prevent radial movements of the distributor sleeve (61 ).

11. Solid-jacket screw centrifuge (1) according to one of the preceding claims, characterized in that the end faces on the distributor sleeve (61) are machined to conform substantially seamlessly to the contour of the screw hub (308).

12. Solid-jacket screw centrifuge (1 ) according to one of the preceding claims, characterized in that the distributor sleeve (61 ) has a lateral opening (613) penetrating its circumferential wall, through which the product or the suspension to be processed is guided axially from the feed pipe (5) into the distributor sleeve (61 ).

13. Solid jacket screw centrifuge (1 ) according to one of the preceding claims, characterized in that, in the case of a design of the inlet pipe (5) as a stationary inlet pipe (5) which does not rotate during operation, it ends shortly before the opening (613) or that it projects slightly into the distributor sleeve (61 ).

14. Solid jacket screw centrifuge (1 ) according to one of the preceding claims, characterized in that, in the case of a design of the inlet pipe (5) as an inlet pipe (5) which rotates during operation, this is connected to the distributor sleeve (61 ) via a detachable connection.

15. Solid-jacket screw centrifuge (1 ) according to one of the preceding claims, characterized in that the inlet pipe (5) can be pulled axially out of the opening (613) of the distributor sleeve (61 ) and pushed back into it.

16. Solid-jacket screw centrifuge (1 ) according to one of the preceding claims, characterized in that a deflection device (614) is provided inside the distributor sleeve (61 ) which is designed to deflect liquid flow impinging axially on it at least in one or two radial directions and preferably in a further direction.

17. Solid-jacket screw centrifuge (1 ) according to one of the preceding claims, characterized in that the deflection device (614) is conical, wedge-shaped and / or helical in design.

18. Solid-jacket screw centrifuge (1 ) according to one of the preceding claims, characterized in that the deflection device (614) projects radially into the inner wall of the distributor sleeve (61 ), preferably from the area opposite the opening (613) in the direction of the inlet pipe (5).

19. Solid-jacket screw centrifuge (1 ) according to one of the preceding claims, characterized in that the cross-section of the distributor sleeve (61 ) is substantially circular, elliptical, oblong or rectangular.

20. Solid-jacket screw centrifuge (1 ) according to one of the preceding claims, characterized in that the distributor sleeve (61 ) is sealed against the wall of the screw hub (308) by one or more surrounding sealing rings (63).

21. Method for changing a distributor sleeve (61) of a solid-jacket screw centrifuge (1) according to one of the preceding claims, characterized in that, to change the distributor sleeve, a) the screw (3) is pulled out of the drum (2) and that the distributor sleeve (61) is then preferably detached from the screw (3) without disassembling any elements of the screw (3) and pulled radially out of it, b) the new distributor sleeve (61) is then inserted radially back into the screw and secured there, and c) the screw (3) is pushed back into the drum (2).

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