EP4367319A1

EP4367319A1 - Comminuting apparatus

Info

Publication number: EP4367319A1
Application number: EP22738485.6A
Authority: EP
Inventors: Thomas EHL
Original assignee: Voith Patent GmbH
Current assignee: Voith Patent GmbH
Priority date: 2021-07-08
Filing date: 2022-07-05
Publication date: 2024-05-15
Also published as: WO2023280814A1; DE102021117641A1

Abstract

The invention relates to an apparatus (20) and a method for comminuting a cellulose material stack (22), such as cellulose mats arranged in a stack for example, in particular a cellulose bale (25) or a part of a cellulose bale. The apparatus comprises a comminuting device (24) for comminuting the cellulose material, comprising at least one rotatable comminuting tool (26). The apparatus additionally comprises a feed device (30) for feeding the material stack to the comminuting device along a feed path, wherein the feed device comprises a guide device and a conveyor device which are designed to guide the material stack to the comminuting device while maintaining the stack shape of the material stack.

Description

Shredding device

The invention relates to a device for comminuting a cellulose material stack, such as cellulose mats arranged in a stack, in particular a cellulose bale or part of a cellulose bale, with a comminution device for comminuting the cellulose material, which comprises at least one rotatable comminution tool. Furthermore, the invention relates to a method for comminuting a stack of cellulose material.

Such devices, so-called shredders, and corresponding methods are known in principle. The device is usually loaded by feeding the cellulose material to be comminuted from above or from the side by introducing it through a hopper or chute into the device and moving from there in a fundamentally random and disorderly manner in the direction of the comminution tool. If the cellulosic material is a cellulosic bale or a stack of cellulosic mats, it typically disintegrates before it reaches the shredding tool. Depending on the type of shredder, one or more slides can be provided, which additionally convey the cellulose material in the direction of the shredding tool. In some cases, a slide is also used to actively press the cellulose material against the shredding tool with a specific pressure and at defined time intervals in order to support shredding. In the case of known shredders, this also results in a random and unordered arrangement of the cellulose material between the slide and the shredding tool. The pile of cellulose material not only disintegrates during feeding, but also during the shredding process. In some cases, cellulose mats stand up or are pushed over the shredding tool. In order to completely shred cellulose mats that have not been caught by the shredding tool, it may be necessary to move the slide to drive back several times and to press the cellulose mats that have not been comminuted or only partially comminuted again by means of the slide against the comminution tool until all the cellulose material has been comminuted. Viewed over time, particularly since less and less cellulose material to be comminuted remains in the comminuter over time, the comminuter is at most temporarily utilized to its maximum capacity, while in principle a significantly greater throughput would be possible in the same time.

Due to the conventional random and unordered supply of the cellulose material stack to the shredding tool, whether by means of a slide, due to the weight of the cellulose material, or by being drawn in by means of the shredding tool, the shredding performance therefore fluctuates and the maximum possible throughput of the shredder is therefore not achieved.

One object of the invention is to provide a device for comminuting cellulose material with an increased throughput.

The object is achieved by a device having the features of claim 1 and by a method having the features of claim 18 and in particular in that the device has a feed device for feeding the material stack of cellulose material to the comminution device along a feed path. The feed device comprises a guide device and a conveyor device, which are designed to feed the material stack to the comminution device while maintaining a stack shape of the material stack.

In the inventive method for crushing a pulp material stack, such as a stack arranged pulp mats, in particular a pulp bale or part of a pulp bale, the material stack is fed by a feed device along a feed path to a comminution device, the feed device feeding the material stack to the comminution device by means of a guide device and a conveyor while maintaining a stack shape of the material stack. Furthermore, the cellulose material is comminuted by means of at least one rotating comminution tool by a comminution device. The method can be carried out with a device according to the invention.

A cellulosic material stack is to be understood in particular as a commercially available cellulosic bale, which is composed of several cellulosic mats. The stacking direction is generally aligned at least essentially perpendicular to the plane of extension of the stacked cellulose mats. A cellulose mat can form a stack level of the material stack. In particular, viewed in the vertical direction, a lowermost cellulose mat can define a bearing surface of the material stack. The cellulosic material stack can also be just a part of a commercially available cellulosic bale, in particular a part that has a reduced amount of fleas in the stacking direction compared to the entire cellulosic cellulosic bale. In principle, the material stack can also be a stack of several pulp bales stacked along their respective stacking direction. The material stack can be formed at least partially from coherent cellulose material, for example from a cellulose web that has been folded onto itself several times and thus brought into the form of a stack. In principle, cellulose material that is not in the form of a mat can also be assembled into the material stack, with the individual cellulose material parts not necessarily having to be arranged separately from one another in clearly defined stacking levels along the stacking direction, but rather can extend at least partially over several such levels. The cellulose bales used are made up of several individual, stable and compacted cellulose material panels, which are stacked and bundled into a bale. The cellulose bales differ from the cotton bales that are usually very often used in that the cotton bales fall apart very easily and require only a small fraction of defibration.

The sheets of cellulose material used usually have a weight per unit area of greater than or equal to 400 g/m ³ , in particular greater than or equal to 600 g/m ² , preferably less than or equal to 1200 g/m ³ . The plates are very stable and require shredding equipment adapted to these properties for shredding.

By feeding the stack of material to the comminution device according to the invention while maintaining the stack shape, the throughput of the device for comminuting cellulose material can be significantly increased, even when using conventional comminution technology. By means of the device according to the invention and in particular by means of the feed device, the material stack can be placed in a targeted and orderly manner and in particular aligned in a defined orientation in front of the shredding device, or fed to it, so that the material stack is grasped and shredded as a whole by the shredding tool. Deviation of individual cellulose mats in front of the shredding tool is also effectively prevented. The invention can also advantageously increase the comminution quality, since the comminution tool always engages at a defined angle with the cellulose material stack that is supplied in a targeted and orderly manner, as a result of which the cellulose material of the cellulose material stack is comminuted more evenly.

Provision can be made for the comminution device to at least essentially dry comminute the stack of cellulose material. For example, the comminution of the pulp material without the addition of water or other solvents. In particular, it can be provided that a moisture content of about 7% or 10% is not exceeded.

The guide device can be designed to guide the material stack along the feed path in such a way that it retains its stack shape up to and during the comminution, in particular in that the guide device is always in contact with the material stack along the feed path on one or more sides and /or subjected to a stabilizing force.

The conveyor device can be designed to actively convey the material stack along at least one section of the feed path towards the comminution device, in particular along at least one section of the guide device. A conveying speed and/or a feed force transmitted to the material stack by the conveying device can be adapted to one or more operating parameters of the comminution device (e.g. a comminution speed or rotational speed of the comminution tool). A substantially constant or at least not excessively fluctuating cellulosic material flow can be supplied to the comminution device by the conveying device. In this way, consistently high shredding performance and shredding quality as well as a piece size of the shredded pulp material that is as homogeneous as possible are achieved.

The guide device and the conveyor device can be formed by separate parts or components. However, certain components of the feed device can be provided both for guiding and for conveying the stack of material and can therefore be attributed to both the guiding and the conveying device. The conveying and/or guiding device can be designed to feed the material stack to the comminuting device along a linear movement direction, in particular the entire Feed path run linear. However, the feed path can also have two or more sections that have a different spatial orientation.

The comminution device can be designed as a single-shaft comminutor with a rotatable comminution tool or as a multi-shaft comminutor with a plurality of rotatable comminution tools. The direction of rotation of the comminution tools can be selected in such a way that an additional stabilization of the material stack is achieved during feeding and/or comminution. For example, the direction of rotation of a single-shaft shredder can be selected such that a blade moves through the stack of material in the direction of the support surface of the stack of material, with which it rests, for example, on the guide device.

Further embodiments of the invention are indicated in the dependent claims, the description and the accompanying drawings.

According to one embodiment, the conveying device is designed to move the material stack along the feed path in a conveying direction that is oriented perpendicular to a stacking direction of the material stack. The stacking planes of the material stack, formed for example by individual cellulose mats, are thus arranged parallel to a feed plane, the feed plane corresponding to the plane on which the material stack rests while it is being fed to the shredding device. The feed plane can be defined by a guide surface of the guide device, on which the material stack is advanced by means of the conveyor device in the direction of the comminution device, and/or by the conveyor device, in particular a support plane of the conveyor device on which the material stack rests. The feed level can correspond to the level on which a stack level of the stack of material that is lowest in the direction of gravity can rest. So it can be achieved that one Crushing tool, in particular cutting of the crushing tool, come into engagement at approximately the same angle with all stack levels of the material stack in order to achieve a high crushing quality.

Alternatively or additionally, an axis of rotation of the at least one rotatable comminution tool can be arranged perpendicular to the stacking direction of the material stack and/or perpendicular to the conveying direction when the material stack is fed to the comminution device.

The guide device can have a florizontal section, for example a guide surface or a guide channel, which is designed to guide the material stack in a horizontal direction at least substantially perpendicularly to its stacking direction. Alternatively or additionally, the guide device can have a vertical section, for example a guide shaft, which is designed to guide the material stack at least substantially parallel to its stacking direction in the vertical direction. If dimensioned appropriately, the guide shaft can serve as a bale magazine for storing a supply of work. The stacking shape of the material stack in the stacking direction can be maintained, in particular in the vertical section, by the weight of the material stack itself. The vertical section and/or the florizontal section can be designed in such a way that displacement of the cellulose material within the material stack, in particular perpendicular to the stacking direction, is prevented, for example by appropriate walls that stabilize the material stack.

The conveying device can be motor-driven, in particular by means of an electric motor. In order to ensure a targeted supply of the material stack to the shredding device, for example with a defined feed force, a conveying speed of the motorized drive can be controllable. The conveyor device can have a pusher which is designed to push the material stack over a guide surface of the guide device in the direction of the comminution device, in particular to feed it to the comminution device. The feed rate can be constant. The guide surface can define the feed plane. The fleas of the material stack to be conveyed in the stacking direction can be defined by the fleas of a sliding surface of the slide in the stacking direction. The sliding surface of the slide can be aligned perpendicular to the guide surface of the guide device and/or parallel to the stacking direction of the material stack. The slide can be positioned between a first end position, in which the stack of material can be arranged between the slide, in particular the sliding surface, and the shredding device, and a second end position, in which the slide, in particular the sliding surface, is at least approximately in contact with the shredding device. be adjustable.

According to one embodiment, the conveyor device comprises a lower conveyor device, in particular a lower conveyor belt or a lower drum or roller conveyor, which is designed to transport a stack of material resting on it along the feed path in the direction of the shredding device. The lower conveying device can define a feed plane for the material stack and/or at the same time serve as a guide surface for the material stack. A lower roller or roller conveyor can have one or more driven transport rollers or rollers, which can optionally be designed as spiked rollers or spiked rollers, on the surface of which spikes, pins and/or spikes serve as carriers for the material stack. In this way, the greatest possible feed force can be exerted on the material stack. A lower conveyor belt can be designed, for example, as a slat conveyor belt, which means that soiling of the surrounding area is kept to a minimum, since it may also be from the cellulose material stack Parts that have been torn out or broken out do not fall through the slat conveyor belt, but are also fed to the shredding device. A lower conveyor belt can also have spikes, spikes or pins, for example screwed or welded on, as carriers for the material stack.

Alternatively or additionally, the conveyor device can comprise an upper conveyor device, in particular an upper conveyor belt or an upper roller or roller conveyor, which is designed to engage with the material stack on a side facing away from its support surface in order to transport it along the feed path in the direction of the to transport crushing device. As described in connection with the lower conveying device, the upper conveying device can have spikes, pins or spikes as carriers for the material stack. An upper drum or roller conveyor may include one or more powered transport drums or rollers. A feed plane of the stack of material defined by the lower conveyor may be oriented parallel to a plane in which the upper conveyor engages the stack of material.

The lower conveyor and the upper conveyor can be arranged vertically spaced from each other in such a way that the material stack can be arranged between them, in particular with the stacking direction extending from the lower conveyor to the upper conveyor, in particular perpendicular to a feed plane defined by the lower conveyor. In order to maintain the stacking shape of the material stack, the distance between the lower and the upper conveyor device can be selected in such a way that a sufficiently high contact pressure is exerted on a material stack arranged between them in the stacking direction that the friction between the stacking planes of the material stack is large enough to move the material stack to be able to feed the crushing device as a whole without the material stack decays. The two conveyors can be operated synchronously. This can be achieved, for example, by a corresponding control of drive units of the devices or by a forced mechanical coupling of the devices.

In order to be able to convey stacks of material with a height that differs in the stacking direction, the distance between the lower and the upper conveying device can be variable. For this purpose, the height of the upper and/or the lower conveying device can be adjusted along the stacking direction of a stack of material to be conveyed. Different sections of the upper and/or lower conveying device can be adjustable to different heights, for example individual transport cylinders or rollers can be individually adjustable in height. The height adjustment can be actively controlled or regulated or be purely mechanical, in each case a defined, possibly preset, contact pressure being able to be exerted on a stack of cellulose material.

For efficient adaptation to material stacks with certain height deviations in the stacking direction, the transport rollers or rollers of the lower and/or upper conveyor device can have a diameter that corresponds to at least twice the maximum expected height deviation of different material stacks to be shredded in the stacking direction. This means that the conveyor can be independently adjusted to different material stack heights.

According to one embodiment, the feed device comprises a store, for example a chute, for storing cellulose material in the form of at least one store stack, so that uninterrupted operation of the device is ensured. In the store, a plurality of material stacks can be stacked one above the other, ie in a single storage stack, or one behind the other, ie in several storage stacks arranged one behind the other, in particular with stacking directions aligned parallel to one another. In the latter case, for example, a storage area or a storage channel can be provided for storing the storage stack. The stacking direction of the storage stack can be arranged parallel to the stacking direction of the material stack.

A plurality of material and/or storage stacks can be arranged one behind the other in the conveying direction along the feed path with the stacking direction aligned parallel to one another, in particular in such a way that a material stack to be fed to the shredding device first can be brought into contact with a subsequent material and/or storage stack. With this arrangement, the material stack to be comminuted first can be fed to the comminution device without itself being in engagement with the conveyor device, in that it is pushed, so to speak passively, from the subsequent material and/or storage stack actively conveyed by the conveyor device in the direction of the comminution device is advanced.

According to a further embodiment, the material stack can be separable from the storage stack or detachable from it, in particular by means of the conveyor device or by means of a part of the conveyor device. For example, it can be provided that the cellulose material of the material stack is separated or sheared off from the storage stack when the fire is released. The conveying device can be designed to successively sort out stacks of material to be shredded from the storage stack in a clocked operation and to feed them to the shredding device.

According to a further embodiment, the device comprises a counter-holder, which is designed to fix cellulose material of the storage stack in the storage during the sorting out of the material stack and/or the feeding of the material stack to the shredding device, in particular in a direction parallel to the conveying direction. The counter-holder can also assume an adjustment function in order to optimize and/or stabilize the stack shape of the storage stack. The counter-holder can comprise at least one counter-holder plate which is in engagement with the storage stack, in particular in a direction parallel to the stacking direction of the storage stack. The counter-holder can be motor-driven and/or mechanically pretensioned in a counter-holder direction, in particular for automatic counter-holding and/or adjustment. In order to enable material stacks of different heights to be sorted out, the counter-holder can be designed to be height-adjustable.

The conveying device can have at least one hold-down device, which is designed to apply a hold-down force to the material stack in the stacking direction in order to maintain the stack shape of the material stack. The at least one hold-down device can be positioned along the feed path so close to the comminution device that it effectively prevents individual cellulose mats from standing up and/or individual cellulose mats from escaping in front of the at least one comminution tool and maintaining the stacked shape of the material stack while it is still being fed to the Crushing device and thus ensures a detection of all stack levels by the crushing tool. The hold-down device can be fixed statically in a suitable position. For example, a static hold-down device can be formed by a wall element of a guide channel and/or guide shaft. In order to be able to stabilize material stacks of different heights in the stacking direction, the hold-down device can be adjustable in height. Alternatively or additionally, the hold-down device can be prestressed into a hold-down position, for example by means of a spring, so that it automatically adapts to material stacks of different heights. In principle, an upper conveying device can also serve as a hold-down device. The hold-down can be such be regulated so that a defined hold-down force is always exerted on a material stack.

According to one embodiment, an axis of rotation of the at least one comminution tool is arranged at least essentially in a feed plane defined in particular by the guide device and/or conveyor device. In particular, it can be provided that the axis of rotation of the at least one comminution tool is not arranged below the feed plane. Reliable removal of the comminuted cellulose material from the comminution tool can thus be ensured.

According to one embodiment, a connecting line between the axis of rotation of the at least one comminution tool and an end point of the feed path encloses an angle of at most 30° with a feed plane. An end point of the feed path can be formed, for example, by an end of a guide surface facing the comminution tool, on which the material stack is moved in the direction of the comminution device. An end point of the feed path can also be defined by the point at which the stack of material first comes into contact with the crushing tool in the conveying direction. An arrangement of the axis of rotation of the at least one comminution tool outside of the feed plane can be particularly advantageous if the comminution device draws in the stack of material automatically.

In some embodiments, the comminution device comprises at least two rotatable comminution tools, for example in the case of a multi-shaft comminutor. An axis of rotation of a first comminution tool can be arranged above and an axis of rotation of the second comminution tool below the feed plane, in particular a guide surface. The first and the second Crushing tools can rotate in opposite directions of rotation, so that they pull the stack of material to be crushed into the crushing device in the conveying direction.

The comminution device is suitable for paper and/or tissue machines and has corresponding dimensions and capacities for the comminution of cellulose materials.

According to a further embodiment, the cellulose material used has a basis weight of greater than or equal to 400 g/m ³ , in particular greater than or equal to 600 g/m ² , preferably less than or equal to 1200 g/m ³ . Advantageously, the necessary quantities of starting material can thus be stored in a space-saving manner. However, the high basis weight also places special demands on the shredding devices used.

The axes of rotation of the at least two rotatable comminution tools can be offset in the conveying direction for improved drawing-in of the material stack.

The at least one rotatable shredding tool can be designed as a shredding roller or as a shredding shaft, the diameter of which is greater than the height of the material stack in the stacking direction. If the diameter of the comminution tool is sufficiently large, it is always in engagement with the stacking planes of the cellulose material stack at approximately similar angles, in particular always essentially perpendicular to the stacking direction of the material stack, resulting in a particularly high comminution quality. A crushing roller can have cutting edges on its surface for crushing the cellulose material. A shredding shaft can have one or more cutting discs for shredding the cellulose material. According to a further embodiment, the comminution device comprises a sieve downstream of the at least one comminution tool for size selection of the comminuted cellulose material, as a result of which a particularly high degree of homogeneity of the comminuted cellulose material can be achieved with regard to its piece size.

Advantageous embodiments of the invention are described below purely by way of example with reference to the accompanying drawings. Show it:

Fig. 1 shows a time course of the throughput of a

Crushing device according to the prior art;

Fig. 2 shows a time course of the throughput of an inventive

crushing device;

3 shows a crushing device with a single-shaft

Crushing device and a pusher for feeding pulp material according to a first embodiment;

Fig. 4 a crushing device with a multi-shaft

Crushing device and a pusher for feeding pulp material according to a second embodiment;

5 shows a comminuting device with a single-shaft

Crushing device and a lower and an upper conveyor belt for feeding pulp material according to a third embodiment;

6 shows a comminuting device with a single-shaft

Crushing device and a lower conveyor belt and a upper roller conveyor for feeding pulp material according to a fourth embodiment.

1 schematically shows a course 10 of a throughput of a shredding device with a shredding shaft and a controlled slide (not shown) according to the prior art when shredding a cellulose material stack composed of layered or stacked cellulose mats. Such a shredder is fed by throwing or unguided sliding of the cellulose material stack into the shredding device by the effect of gravity. The cellulose material stack disintegrates at least partially during the feeding and during the comminution process, resulting in a random and disordered arrangement of the cellulose mats in the comminution device and thus also in front of the comminution shaft. In a first feed phase 12.1 of the comminution process, which follows the throwing in of the cellulose material stack, the pusher grasps the uncomminuted cellulose mats of the cellulose material stack and pushes them in the direction of the shredding shaft. The disordered and randomly arranged cellulose mats partially stand up in front of the shredding shaft and/or are pushed over it. Some cellulose mats may not be caught by the pusher at all. Overall, since there are many uncomminuted cellulose mats in the comminution device, there is initially a relatively high throughput 14.1, which is subject to strong fluctuations, however, since the disordered cellulose mats are sometimes at unfavorable angles to the crushing shaft, are pushed over it, or by the slide not be recorded at all.

In order to also shred the cellulose mats that were not caught by the shredding shaft in the first feed phase 12.1, the slide initially moves back from the shredding shaft in a first retraction phase 16.1. Meanwhile, the shredding throughput drops to 0. Then, in a second feed phase 12.2, the pusher pushes the pulp mats that are not shredded or only partially shredded against the shredding shaft, with a significantly reduced throughput 14.2 compared to the first feed phase 12.1, since only less pulp material to be shredded is left in the shredding device. A second retraction phase 16.2 and a third feed phase 12.3 follow in order to comminute remaining uncomminuted cellulose material, with the retraction and feed phases generally having to be repeated until all the cellulose material in the cellulose material stack has been comminuted. Typically, the throughput 14 continues to fall with each additional feed phase 12 until new material is fed.

A shredding device according to the prior art, in which a random and unordered supply of a stack of pulp material takes place, is therefore, as shown in FIG. 1, only partially utilized, whereby the maximum possible amount of pulp material is not shredded per unit of time.

A constant throughput over time during the supply of a stack of cellulose material by means of a pusher is shown in FIG. During a feed phase 12, the comminution capacity of the comminution device is well utilized with a consistently high throughput. A stack of cellulose material fed in during the feeding phase 12 is completely comminuted. After a subsequent withdrawal phase 16, another cellulose material stack is already being fed in and comminuted in a renewed feeding phase 12. According to FIG. 2, the throughput is constantly high during the supply of each stack of cellulose material, so that the maximum possible amount of cellulose material is comminuted per unit of time. An increase in the throughput according to FIG. 2 can be achieved by feeding the cellulose material stack to be shredded to the shredding shaft or a shredding device in a generally targeted and orderly manner, so that on the one hand the stack shape of the cellulose material stack is maintained and on the other hand a defined orientation of the cellulose material stack with respect to the shredding tool is maintained will. Such a targeted and ordered supply of the cellulose material stack can be achieved with the devices according to FIGS. 3 to 6 .

3 shows a device 20 for comminuting a cellulose material stack 22, also referred to as material stack 22 below. The comminution device 20 has a comminution device 24 for comminuting the cellulose material stack 22 with a rotatable comminution tool 26, which in the present exemplary embodiment is designed as a comminution roller 28 of a single-shaft comminutor. The surface of the shredding roller 28 has cutting edges (not shown) which, when the shredding roller 28 rotates in the direction of rotation 29 , engage the cellulose material of the supplied cellulose material stack 22 from a free upper side 66 and shred it. In order to be able to grasp and shred the entire stack of material 22 at the same time, the shredding roller 28 has a diameter D that exceeds the fleas of the material stack 22 in the stacking direction S, with the diameter D according to the first embodiment being at least twice the fleas of the material stack 22.

In the exemplary embodiment shown, the cellulose material stack 22 is formed by cellulose mats 23 which are stacked on top of one another along a stacking direction S, which extends perpendicularly to a mat surface of the individual cellulose mats 23 . In the exemplary embodiment of FIG. 3, the cellulose material stack 22 is part of a commercially available cellulose bale 25, specifically just around half of a pulp bale 25, which has been halved in height with respect to the stacking direction S. In principle, however, the size of the device 20 can be adjusted so that, for example, a complete cellulose bale 25 can be comminuted as a whole.

In order to feed the material stack 22 to the shredding device 24 in a targeted and orderly manner and while maintaining the stack shape of the material stack, the device 20 has a feed device 30 with a guide device 32 and a conveyor device 34 . The conveyor device 34 is designed to move the material stack 22 along the feed path in sections actively in a conveying direction 36 towards the comminution device 24 . The conveying direction 36 is oriented perpendicularly to the stacking direction S of the material stack 22 so that the entire material stack 22 is moved parallel to its stacking planes, which is defined by the mat surface of the cellulose mats 23 .

According to the first embodiment, the conveying device 34 comprises a slide 38 which, with a sliding surface 40, grasps a side surface of the material stack 22 facing away from the crushing device 24 in order to push it in the direction of the crushing device 24 and feed it in a controlled manner. The material stack 22 is moved by means of the slide 38 over a horizontally extending guide surface 42 of the guide device 32 on which the material stack 22 rests. The guide surface 42 also defines a feed plane Z of the material stack 22 to the shredding device 24. The individual cellulose mats 23 of the material stack 22 are aligned parallel to the feed plane Z.

The slide 38 is motor-driven, for example electrically or hydraulically, and can be moved between a first end position, in which the unshredded stack of material 22 can be arranged in an aligned manner between the slide 38 and the shredding roller 28, and a second end position, in which the sliding surface 40 is almost in contact with the crushing roller 28, are moved. The slide 38 can be driven in a regulated manner and in particular can be controlled in such a way that it feeds the material stack 22 to the shredding roller 28 at a constant feed rate or constant feed force.

In addition to the guide surface 42 embodied as a horizontal section, the guide device 32 has a vertical section which is embodied as a guide shaft 52 according to FIG. 3 . In the vertical section of the guide device 32, the material stack 22 is guided along the feed path in the vertical direction parallel to its stacking direction S, so that the stacked shape of the material stack 22 is maintained. Contributing to this is the weight of the cellulose mats 23 lying on top of one another, which stabilizes the stack shape during the vertical movement through the guide shaft 52 .

The guide shaft 52 is formed on the one hand by at least one housing wall 54 of the shredding device 20 and on the other hand is delimited by a counter-holder 56, which is embodied as a holding plate that is arranged parallel to the stacking direction S of the material stack 22 and perpendicular to the conveying direction 36. A vertical upper side of the guide chute 52 is accessible for introducing pulp material to be comminuted into the feed device 30 . The counter-holder 56 is arranged at a distance from the guide surface 42 in the stacking direction S in such a way that the material stack 22 can pass between them.

According to the first embodiment, the guide shaft 52 serves as a store 58 of the feed device 30 in which cellulose material can be stored in the form of a store stack 60 . The storage stack 60 can have a plurality of pulp bales 25 arranged parallel to one another in the vertical direction aligned stacking directions S include. The stack of material 22 to be shredded corresponds to a certain extent to the lowermost part of the storage stack 60 in the vertical direction, resting on the guide surface 42 and which can be grasped by the slide 38 .

If slide 38 is in its first end position, in which it has been pulled back to behind the end of storage stack 60 facing away from shredding roller 28, storage stack 60 and in particular material stack 22 can be pushed in the vertical direction between slide 38 and shredding roller 28 onto the Guide surface 42 slide. If the slide 38 moves during a feed phase 12 in the conveying direction 36 to its second end position, the material stack 22 is completely crushed by the crushing roller 28 (FIG. 2). The slide 38 is then returned to its first end position in a retraction phase 16, with the throughput rate dropping to 0 for a short time. A subsequent material stack 22, according to FIG. 3, for example the second half of a pulp bale 25, can then slide out of the storage stack 60 onto the guide surface 42 and be comminuted in the subsequent feed phase 12. In this way, the cellulose material stored in the storage stack 60 is successively shredded.

The material stack 22 to be shredded is separated out by means of the slide 38, which is moved alternately in a clocked operation between feed phases 12 and retraction phases 16. Meanwhile, the counter-holder 56 serves to fix the cellulose mats 23 stored in the storage stack 60 in the conveying direction 36 so that they are not accidentally carried along by the material stack 22 in a disorderly manner in the direction of the comminution device 24 . If there is a certain connection between the stack 22 to be separated out and the material lying above it, this is sheared off when the stack 22 is advanced. A hold-down device 62 is arranged in the conveying direction 36 between the counter-holder 56 and the shredding roller 28 along the feed path, which ensures that the cellulose mats 23 of the separated material stack 22 are subjected to a hold-down force in the stacking direction S, which is sufficient for the stack shape of the material stack 22 is also maintained while it is being fed to the crushing roller 28 and while it is being crushed. This prevents individual cellulose mats 23 from standing up or moving away and ensures that all cellulose mats 23 are simultaneously grasped and effectively and homogeneously comminuted. On the slide 38 side, the material stack 22 is stabilized in stack form along the stacking direction S by the weight of the storage stack 60 and the latter by the counter-holder 56 .

According to the first embodiment, the axis of rotation R of the shredding roller 28 is arranged essentially in the feed plane Z, which is extended beyond the guide surface 42 . Comminuted cellulose material, which is separated from the cellulose material stack 22 by the comminution tool 26 rotating in the direction of rotation 29 , can be transported away in the direction of a discharge box 44 without any problems using this arrangement. In order to ensure a high flomogeneity of the comminuted cellulose material discharged in the discharge sifting unit 45 with regard to the piece size present, the comminution roller 28 is followed by a sieve 46 for size selection. The material discharge of the shredded material can be supported with an air flow, also to reduce the formation of dust.

FIG. 4 shows a comminuting device 20 according to a second embodiment, which largely corresponds to the comminuting device 20 according to the first embodiment. The height of the slide 38 or the slide surface 40 is selected to be lower in relation to a cellulose bale 25, so that the material stack 22 to be shredded, which is sorted out of the storage stack 60 by means of the slide 38, has a lower height in the stacking direction S than according to FIG. 3. However, the basic mode of operation of the conveying device 30 and of the store 58 is unchanged.

According to the second embodiment, the comminution device 24 is designed as a multi-shaft comminutor with two rotatable comminution tools 26, which has a first comminution shaft 28.1 and a second comminution shaft 28.2. The first and second shredding shafts 28.1, 28.2 are each provided with a plurality of cutting discs (not shown) which are spaced apart from one another and are used to shred the stack of cellulose material 22, with the cutting discs of the first shredding shaft 28.1 engaging between the cutting discs of the second shredding shaft 28.2 .

The axis of rotation R1 of the first shredding shaft 28.1 is arranged above the feed plane Z defined by the guide surface 42, the axis of rotation R2 below the feed plane Z, with the axes of rotation R1, R2 being offset from one another in the conveying direction 36. A connecting line between an end point of the feed path facing the comminution device 24, indicated here by an end point 43 of the guide surface 42, and the axis of rotation R1 of the first comminution shaft 28.1 encloses an angle W1 of at most 30° with the feed plane Z. The same angular relation can apply to the angle W2 of the axis of rotation R2 of the second crushing shaft 28.2 and the feed plane Z.

In addition, the shredding device 24 has a first cleaning shaft 64.1, which engages in the cutting gaps between the cutting discs of the first shredding shaft 28.1 and removes pulp residues from them, and a second cleaning shaft 64.2, which engages in the cutting gaps between the cutting discs of the second shredding shaft 28.2 and removes pulp residues from them freed. The first and the second cleaning shaft 64.1, 64.2 are arranged with respect to the feed plane Z outside of the first and second shredding shaft 28.1, 28.2, ie the first cleaning shaft 64.1 is arranged above the first shredding shaft 28.1 and the second cleaning shaft 64.2 is arranged below the second shredding shaft 28.2. The first and second cleaning shafts 64.1, 64.2 each rotate in the same direction of rotation as the associated first and second shredding shafts 28.1, 28.2. Thus, the multi-shaft shredder according to FIG. 4 is a four-shaft shredder.

The first and second shredding shafts 28.1, 28.2 are driven in opposite directions of rotation 29.1, 29.2, specifically in such a way that the two shredding shafts 28.1, 28.2 rotate towards one another on their side facing the material stack 22. This arrangement ensures that the rotating first and second shredding shafts 28.1, 28.2 pull the material stack 22 into the shredding device 24 in the conveying direction 36. In this way, the cellulose mats 23 of the material stack 22 are stabilized in stack form on the side of the comminution device 24 and individual cellulose mats 23 are prevented from standing up or moving away in front of the comminution device 24 . An additional hold-down device 62 in front of the crushing device 24 can be dispensed with in the second embodiment.

5 and 6 show a device 20 for comminuting stacks of cellulose material 22 according to a third (FIG. 5) and a fourth embodiment (FIG. 6), which are each designed for a higher throughput than the devices 20 of FIGS are and have an alternative feed device 30 . Specifically, the crushing devices 20 of FIGS. 5 and 6 are designed to crush commercially available cellulose bales 25 as a material stack 22, which can have a size of about 50 to 60 cm in the stacking direction S, as a whole. In principle, however, a different stacking height of the material stack 22 can also be provided. Both devices 20 of FIGS. 5 and 6 each have a crushing device 24 with a single crushing roller 28 whose diameter D exceeds the height of the material stack 22 in the stacking direction S. The direction of rotation 29 of the shredding roller 28 is selected in each case so that a cutting edge (not shown) of the shredding roller 28 first strikes a free upper side 66 of the material stack 22, which faces away from a bearing surface of the material stack 22 with which it rests on a guide device 32 . The cutting edge is then moved through the material stack 22 towards the feed plane Z, ie toward the bearing surface of the material stack 22. This prevents the material stack 22 from fanning out at its end facing the crushing device 24.

The feed device 30 provides a substantially horizontal feed of the material stack 22 to the shredding device 24 . The conveyor device 34 of the devices 20 of FIGS. 5 and 6 each includes a lower conveyor device 68 which is designed to convey a material stack 22 resting thereon along the feed path in the direction of the comminution device 24 . The lower conveyor devices 68 each comprise a motor-driven first lower conveyor belt 70.1 and a motor-driven second lower conveyor belt 70.2. These each have a receiving plane on which the material stack 22 rests with its support surface. The receiving plane, in particular of the second lower conveyor belt 70.2, which precedes the comminution device 24 along the feed path, defines the feed plane Z in each case.

To a certain extent, the first lower conveyor belts 70.1, which are located upstream of the respective second lower conveyor belts 70.2 along the feed path, serve as storage 58 for storing pulp bales 25, which serve as storage stacks 60 arranged one behind the other as a supply of pulp material to be shredded when the shredding device 24 on next arranged stack of material 22 was crushed. A counter-holder 56 for fixing the storage stack 60 in place can be dispensed with here, since it is not necessary to separate the material stack 22 from a vertically stacked supply.

In order to ensure that the material stack 22 is fed to the shredding device 24 in a targeted and orderly manner while maintaining the stack shape of the material stack 22, the conveyor devices 34 according to the third and fourth embodiment each comprise an upper conveyor device 72. The upper conveyor device 72 is in the stacking direction S from the lower conveying device 68 by approximately the fleas of a material stack 22 and is designed to engage in each case with the free upper side 66 of the material stack 22 on its side facing away from the support surface in order to move the material stack 22 along the feed path in the direction of the shredding device 24 to move. By actively conveying the stack of material 22 by means of the lower and the upper conveying device 68, 72, it is effectively moved against the crushing roller 28. As a result, the conveying function of an alternately working slider can be replaced. This eliminates the withdrawal phases, which means that the shredding process runs steadily and efficiently with increased throughput. At the same time, a sufficiently high hold-down force is exerted on the material stack 22 by the upper conveying device 68 in order to generate sufficient friction between the stacked cellulose mats 23 in order to be able to feed the material stack 22 as a whole to the shredding roller 28 . If required, a certain compression of the stack 22 can also be provided.

According to the third embodiment of FIG. 5, the upper conveyor device 72 is designed as an upper conveyor belt 74, which is arranged at the same position as the second lower conveyor belt 70.2 with respect to the conveying direction 36. As can be seen in FIG. 5, a material stack 22 to be comminuted does not stand with the upper one until it has been completely comminuted by the comminuting device 24 and the second lower conveyor belt 74, 70.2, since these already end at a certain distance d in front of the crushing roller 28 along the conveying direction 36. However, in order to move the stack of material 22 with constant advance in the conveying direction 36 against the shredding roller 28 until it is completely shredded, the third embodiment provides that the pulp bale 25 following the stack of material 22, which is already in engagement with the second lower and upper conveyor belt 70.2 , 74 is in close contact with the material stack 22 in the conveying direction 36, so that the following, actively transported, cellulose bale 25 acts as a sort of pusher for the material stack 22, which is passively fed from the following cellulose bale 25 to the comminution device 24 until it is completely comminuted . To guide the part of the stack 22 that has not yet been comminuted in area d, a shaft-like guide device (not shown) or the like can be present.

In order to enable the supply of cellulose bales 25 with certain differences in height in the stacking direction S, the upper conveying device 68 has a height adjustment 76 . This can be done by a linear displacement of the entire upper conveyor belt 74 in the vertical direction. Alternatively or additionally, a pivoting lever for adjusting the upper conveyor belt 74 can be provided. The band 74 can be pressed against the bale 25, for example, with a mechanical pretension or by means of an actively operable device (possibly with a controllable motor).

According to the fourth embodiment of FIG. 6, a roller conveyor 78 is provided as the upper conveyor device 72, which is formed by a plurality of driven spiked rollers 80. The diameter of the spiked rollers 80 is at least twice as large as the maximum expected difference in fleas in the cellulose bales 25 to be crushed, so that the upper conveying device 68 can be automatically adapted to cellulose bales 25 with different fleas. In addition, the roller conveyor 78 is adjustable as a whole in the fleas to adapt to a new pulp bale height to be adjusted, for example when changing the pulp bale supplier.

In addition, the individual spiked rollers 80 are guided in such a way that their height can be adjusted individually and independently of one another (height adjustment 76), so that flexible adaptation is also achieved to transitions between two pulp bales 22, 25 with different heights in the stacking direction S (Fig. 6 ). This ensures that in the event that cellulose bales 25 with a different height in the stacking direction are located between the upper and lower conveyor devices 72, 68, all transport rollers 80 have a sufficient hold-down force in the stacking direction and a feed force in the conveying direction 36 on the material stack that is contacted in each case 22 or 25 pulp bales to feed them while maintaining the stack shape of the shredding device.

According to the third and fourth embodiment, the conveying device 32 with the lower and upper conveying device 68 , 72 is used on the one hand for actively conveying the material stack 22 in the conveying direction 36 towards the crushing device 24 . On the other hand, the same components also fulfill the function of a guide device 32, which ensures a targeted and orderly feeding of the material stack 22 to the shredding device 24 while maintaining the stack shape, with the function of a hold-down device 62 already being covered by the components of the guide device 32.

The feed devices 30 according to the third and fourth embodiment can be of any length. If the feed force required for feeding to the shredding roller 28 cannot be transferred to a single stack of material 22, the feed device 30 can be extended in such a way that two or more pulp bales 25 are gripped by the feed device 30, in particular the conveyor device 34, at the same time and are actively transported in order to generate the necessary feed force in the conveying direction 36 .

In the third and fourth embodiment, a control of the conveyor device 34 can be provided, which, for example in the event of an overload of the comminution device 24, reduces the feed force or causes the material stack 22 to “reverse” against the conveying direction 36 away from the comminution device 24.

The principle of the targeted, ordered supply of cellulose material stacks 22 to a comminution device 24 according to FIGS. 5 and 6 is particularly suitable for high throughput capacities. From an upstream handling system for cellulose bales 25, these can be transferred directly to the feed device 30 of the shredding device 20 without the need for additional loading devices. In addition, according to the third and fourth embodiment, there is no “dead time” in which the throughput drops to 0, since a continuous supply of pulp to the shredding device 24 is provided and retraction phases 16 of a slide 38 are omitted. Furthermore, the device according to FIGS. 5 and 6 has a lower overall height than the devices 20 shown in FIGS. 3 and 4, since horizontal loading is possible and a vertical section is dispensed with. However, it is entirely possible to combine the embodiment of FIGS. 5 and 6 with a supply chute, for example similar to the chute 52 according to FIG. 3 or 4. The horizontal part of the stack 60 can then buffer the retraction phase 16 of the slide 38 so that the crushing device 24 can be supplied with a continuous flow of bales despite the clocked operation of the slide 28 . Reference character list

10 History of throughput performance

12 feeding phase

12.1 first feeding phase

12.2 second feeding phase

12.3 third feeding phase

14 throughput

14.1 Throughput of the first feeding phase

14.2 Throughput of the second feeding phase

14.3 Throughput of the third feeding phase

16 retreat phase

16.1 First Retreat Phase

16.2 Second Retreat Phase

20 Device for crushing a cellulosic material stack

22 pulp material stacks

23 pulp mats

24 shredding device

25 pulp bales

26 shredding tool

28 shredding roller

28.1 first crushing wave

28.2 second crushing shaft

29 Direction of rotation of the shredding roller

29.1 Direction of rotation of the first crushing shaft

29.2 Direction of rotation of the second crushing shaft

30 feeder

32 guiding device

34 conveyor

36 conveying direction

38 sliders

40 sliding surface

42 guiding surface

44 discharge box

45 discharge direction

46 screens

52 guide slot

54 housing wall of the crushing device

56 counter holder 58 accumulator 60 accumulator stack 62 hold-down device

64.1 first wave of cleaning

64.2 second wave of cleaning

66 free top of the material stack 68 lower conveyor 70 lower conveyor belt

70.1 first lower conveyor belt

70.2 second lower conveyor belt 72 upper conveyor

74 upper conveyor belt

76 flea adjustment of the upper conveyor

78 roller conveyor

80 Spiked roller d Distance between the upper and lower conveyor belt and the shredding roller

D diameter of the crushing tool

R Axis of rotation of the shredding tool

R1 Axis of rotation of the first crushing shaft

R2 Axis of rotation of the second crushing shaft

S stacking direction

W1 Angle between the axis of rotation of the first shredding shaft and the feed plane

W2 angle between the axis of rotation of the second shredding shaft and the feed plane Z feed plane

Claims

Expectations

1. Device (20) for comminuting a cellulose material stack (22), such as cellulose mats (23) arranged to form a stack, in particular a cellulose bale (25) or a part of a cellulose bale (25), with a comminuting device (24) for comminuting the cellulose material , which comprises at least one rotatable crushing tool (26), and having a feed device (30) for feeding the material stack (22) to the crushing device (24) along a feed path, the feed device (30) having a guide device (32) and a conveyor device ( 34) which are designed to feed the material stack (22) to the comminuting device (24) while maintaining a stack shape of the material stack (22).

2. Device (20) according to claim 1, wherein the conveyor device (34) is designed to move the material stack (22) along the feed path in a conveying direction (36) perpendicular to a stacking direction (S) of the material stack (22). is oriented.

3. Device (20) according to claim 1 or 2, wherein the guide device (32) has a floral section, for example a guide surface (42) or a guide channel, which is designed to guide the material stack (22) at least substantially perpendicularly to its stacking direction (S ) in the horizontal direction, and a vertical section, for example a guide shaft (52), which is designed to guide the material stack (22) at least substantially parallel to its stacking direction (S) in the vertical direction.

4. Device (20) according to at least one of the preceding claims, wherein the conveyor device (34) is motor-driven.

5. Device (20) according to at least one of the preceding claims, wherein the conveyor device (34) has a slide (38) which is designed to move the material stack (22) over a guide surface (42) of the guide device (32) in the direction of the To push crushing device (24), in particular to feed it to the crushing device (24).

6. Device (20) according to at least one of the preceding claims, wherein the conveyor device (34) comprises a lower conveyor device (68), in particular a conveyor belt (70.1, 70.2) or a cylinder or roller conveyor, which is designed to have a material stack (22) lying on it along the feed path in the direction of the crushing device (24).

7. Device (20) according to at least one of the preceding claims, wherein the conveyor device (34) comprises an upper conveyor device (72), in particular a conveyor belt (74) or a roller or roller conveyor (78), which is designed to to be in engagement with the material stack (22) on a side facing away from its support surface in order to convey it along the feed path in the direction of the comminution device (24).

8. Device (20) according to at least one of the preceding claims, wherein the feed device (30) comprises a store (58), for example a chute (52) for storing cellulose material in the form of at least one storage stack (60).

9. Device (20) according to at least claim 8, wherein the material stack (22) can be separated from the storage stack (60), in particular by means of the conveyor device (34).

10. Device (20) according to at least claim 8 or 9, comprising a counter-holder (56) which is designed to hold cellulose material of the storage stack (60) in the storage (58) during the separation of the material stack (22) and/or the feed of the material stack (22) to the crushing device (24), in particular in a direction parallel to the conveying direction (36).

11. The device (20) according to at least one of the preceding claims, wherein the conveyor device (34) has at least one hold-down device (62) which is designed to hold down the material stack (22) in the stacking direction (S) with a hold-down force to maintain the stack shape of the Material stack (22) to apply.

12. Device (20) according to at least one of the preceding claims, wherein an axis of rotation (R, R1, R2) of the at least one comminution tool (26) is arranged at least essentially in a feed plane (Z) defined by the guide device (32).

13. Device (20) according to at least one of the preceding claims, wherein a connecting line between the axis of rotation (R, R1, R2) of the at least one crushing tool (26) and an end point (43) of the feed path with a feed plane (Z) forms an angle ( W1, W2) of at most 30°.

14. The device (20) according to at least one of the preceding claims, wherein the comminution device (24) has at least two rotatable comminution tools (26), in particular wherein an axis of rotation (R1) of a first comminution tool (26) is above and an axis of rotation (R2) of a second Crushing tool (26) are arranged below a feed plane (Z).

15. Device (20) according to at least claim 14, wherein the axes of rotation (R1, R2) of the at least two rotatable comminution tools (26) are offset in the conveying direction (36).

16. Device (20) according to at least one of the preceding claims, wherein the at least one rotatable shredding tool (26) is designed as a shredding shaft (28.1, 28.2) whose diameter is greater than the height of the material stack (22) in the stacking direction (S).

17. Device (20) according to at least one of the preceding claims, wherein the comminution device (24) comprises a sieve (46) downstream of the at least one comminution tool (26) for size selection of the comminuted cellulose material.

18. Method for comminuting a cellulose material stack (22), such as cellulose mats (23) arranged to form a stack, in particular a cellulose bale (25) or part of a cellulose bale (25), in particular by means of a device (20) for comminuting cellulose material according to one of the preceding claims, in which the material stack (22) is fed by a feed device (30) along a feed path to a shredding device (24), the feed device (30) feeding the material stack (22) by means of a guide device (32) and a conveyor device (34).

Crushing device (30) while maintaining a stack shape of the material stack (22) and in which a crushing device (30) crushes the cellulose material by means of at least one rotating crushing tool (26).