US20250290251A1

US20250290251A1 - Apparatus for processing fibrous materials

Info

Publication number: US20250290251A1
Application number: US19/098,489
Authority: US
Inventors: Wolfgang Mannes
Original assignee: Voith Patent GmbH
Current assignee: Voith Patent GmbH
Priority date: 2022-10-12
Filing date: 2025-04-02
Publication date: 2025-09-18
Also published as: EP4602210A1; WO2024079177A1

Abstract

An apparatus for processing fibrous materials, in particular fibrous material with high stock densities in the HC range, such as waste paper. The apparatus has a pulping module for pulping fibrous material into a fibrous material suspension, and a grading module, coupled to the pulping module, for subsequent grading of the pulped fibrous material suspension. The pulping module has a housing and a first rotor arranged in the housing. The grading module has a housing with a screen for separating the fibrous material suspension fed in into accepted stock and reject, and a second rotor arranged in the housing. The first and second rotors are formed as a common rotor.

Description

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation, under 35 U.S.C. § 120, of copending International Patent Application PCT/EP2023/078157, filed Oct. 11, 2023, which designated the United States; this application also claims the priority, under 35 U.S.C. § 119, of German Patent Application DE 10 2022 126 510.2, filed Oct. 12, 2022; the prior applications are herewith incorporated by reference in their entirety.

FIELD AND BACKGROUND OF THE INVENTION

The invention relates to an apparatus for processing fibrous materials, in particular for pulping and grading fibrous materials with high stock densities in the HC range.
Pulping apparatuses are used to process fibrous raw materials to enable them to be used in the form of a fibrous material suspension, for example, in a machine for producing a fibrous material web, such as a paper web. Waste paper fibers are used as a fibrous raw material, for example. After pulping, the suspension containing fibrous material is treated in a wet screening process in order to retain contaminants foreign to the fibers on a screen on account of their size and then to separate them out. The fibers can pass through the screen openings with a portion of the water.
In this case, different apparatuses, e.g., a continuous LC (low consistency) pulper, a drum pulper, or a discontinuous HC (high consistency) pulper, are used for pulping and the initial coarse grading of fibrous materials, such as waste paper. For grading pulped waste paper, drum screens or flat screen machines are used. These apparatuses each offer specific advantages, such as low investment costs, a low specific energy requirement, charging with complete, unseparated bales of raw material, low maintenance costs, low wear, simplicity of operation, continuous pulping of fibrous materials of high stock densities and the isolation of raw materials that are difficult to pulp.
Owing to the use of different machines for the respective method steps, however, this has the effect in a production plant that transport paths arise between the individual machines since there has not hitherto been a concept for the integration of different processing stages such as, in particular, pulping and coarse grading of fibrous materials in one apparatus.
German published patent application DE 10 2015 206 499 A1 describes an apparatus for pulping fibrous material, in particular for pulping fibrous material with high stock densities in the HC range. The apparatus comprises a housing and working elements arranged in the housing, which can be brought into engagement with the fibrous material. The housing is in the form of an upwardly open trough of U-shaped cross section in which there is arranged a rotor that is rotatable about an axis parallel to the longitudinal axis of the trough and is provided with blade-type working elements, in particular working elements having a low tendency for spinning.
German published patent application DE 10 2015 206 506 A1 describes an apparatus for grading wet, fibrous materials containing dirt, in particular for the initial grading of pulped waste paper, having a housing and a screen, which has a multiplicity of screen openings, through which some of the fibrous material suspension fed to the housing can pass as accepted stock, while another portion of the fibrous material suspension is retained by the screen openings as reject. Disk-shaped elements are arranged on a rotatably mounted rotor in the housing in order to keep the screen free and loosen the reject.

SUMMARY OF THE INVENTION

It is accordingly an object of the invention to provide an apparatus which overcomes the above-mentioned and other disadvantages of the heretofore-known devices and methods of this general type and which provides for an apparatus for processing fibrous materials by means of which both the pulping and the grading of fibrous materials can be carried out safely and without disruption, and which has a compact construction.
With the above and other objects in view there is provided, in accordance with the invention, an apparatus for processing fibrous materials, and in particular fibrous materials with a high material densities in the HC (high consistency) range. The novel apparatus comprises:

- a pulping module for pulping fibrous material into a fibrous material suspension, said pulping module having a pulping module housing and a first rotor with a rotor shaft arranged in said pulping module housing;
- a grading module coupled to said pulping module and configured for subsequent grading of the pulped fibrous material suspension, said grading module having a grading module housing with a screen for separating the fibrous material suspension into accepted stock and reject, and a second rotor with a rotor shaft arranged in said grading module housing; and
- said rotor shaft of said first rotor of said pulping module and said rotor shaft of said second rotor of said grading module being connected to one another and forming a common shaft.

In other words, the objects of the invention are achieved by an apparatus for processing fibrous materials, in particular fibrous material with high stock densities in the HC range, such as waste paper. The apparatus comprises at least one pulping module for pulping fibrous material into a fibrous material suspension, and a grading module, coupled to the pulping module, for subsequent grading of the pulped fibrous material suspension, wherein the pulping module comprises a housing and a first rotor arranged in the housing, and wherein the grading module comprises a housing having a screen for separating the fibrous material suspension fed in into accepted stock and reject, and a second rotor arranged in the housing.
The rotor shaft of the first rotor of the pulping module and the rotor shaft of the second rotor of the grading module are connected to one another and form a common shaft. This favors a compact construction.
In a further development, there is provided a heavy-component separation module arranged between the pulping module and the grading module. It is thereby possible to separate heavy components at an early point in time, and they do not have to pass through the screen module (50). This has an advantageous effect on energy consumption. Moreover, the wear on the screen module can be reduced.
In one advantageous embodiment, it is envisaged that the housing of the pulping module is in the form of a trough extending horizontally along a longitudinal axis. The first rotor comprises a rotor shaft which is mounted so as to be rotatable about an axis of rotation parallel to the longitudinal axis of the housing and has working elements arranged circumferentially thereon, which can be brought into engagement with the fibrous material.
In another advantageous embodiment, it is envisaged that the housing of the grading module is in the form of a trough extending horizontally along a longitudinal axis. The trough is provided in its lower region with a screen bent into a partially circular shape in cross section. The second rotor comprises a rotor shaft which is mounted so as to be rotatable about an axis of rotation parallel to the longitudinal axis of the housing and has clearing elements, arranged circumferentially thereon, for keeping the screen free and for loosening the reject.
In particular, the trough of the housing of the pulping module and/or the trough of the housing of the grading module has, in its lower region, an inner wall of partially circular, in particular semicircular, cross section.
In one advantageous embodiment, the rotor shaft of the first rotor of the pulping module and the rotor shaft of the second rotor of the grading module are connected to one another and form a common shaft.
In a further development, it is envisaged that the rotor shaft of the first rotor of the pulping module and the rotor shaft of the second rotor of the grading module are embodied in one piece in order to form the common shaft.
In particular, a drive module is provided for controlling and driving the common shaft consisting of the rotor shaft of the first rotor of the pulping module and the rotor shaft of the second rotor of the grading module. Driving by a common drive module allows a compact design. In addition, the use of just one drive has an advantageous effect on production costs.
In another embodiment, it is envisaged that the common shaft can be driven at a maximum peripheral speed which is less than 10 m/s and preferably less than 5 m/s.
It is advantageous if the heavy-component separation module is arranged between the housing of the pulping module and the housing of the grading module.
In particular, it is envisaged that the clearing elements of the pulping module are designed as discs set obliquely relative to the axis of rotation of the rotor and are arranged on the rotor shaft in such a way that, as the rotor rotates, the fibrous material suspension and/or the reject are/is pushed backward and forward at least substantially axially.
In one advantageous embodiment, it is envisaged that the smallest radial distance between the working elements and an inner wall of the housing of the pulping module is about 200 mm, preferably 500 mm.
In another advantageous embodiment, it is envisaged that the radial distance between the clearing elements and an inner wall of the housing of the grading module is less than 20 mm.
It is advantageous if an inflow region of the grading module is configured in such a way that the fibrous suspension flows in below the rotor shaft. In particular, inflow in a region 15-20 cm below the axis of rotation of the rotor shaft is advantageous.
In particular, it is envisaged that the screen has a very small height in the inflow region of the grading module and is arranged substantially only in a bottom region. The bottom region extends over a maximum angular range of 90°, preferably 60° and particularly preferably over 45° of the semicircular inner wall. Alternatively, the inflow region can be of screen-free configuration and the screen is arranged only downstream of the inflow region in the grading module.
It is advantageous if the fibrous material to be treated is fed to the housing of the pulping module from above and orthogonally to the axis of rotation or axially with respect to the axis of rotation, wherein the pulped fibrous material can be ejected from the pulping module axially or laterally in such a way that it can be fed continuously to the grading module after pulping.
In one preferred embodiment, a vertical difference in height between the outlet of the pulping module and the inlet of the grading module is provided. By means of this difference in height, the suspension is supplied with kinetic energy by the acting gravitational force. This difference in height is preferably dimensioned in such a way that the fibrous suspension can be fed from the pulping module to the screen module without the need for a pump.
In one preferred embodiment, the outlet of the pulping module is provided with a weir, preferably with an adjustable weir. It is thereby possible to adjust the difference in height and thus also to adjust the potential energy of the suspension.
In a further development, a reject module is provided, which is connected to the grading module in order to discharge the reject from the grading module.
Other features which are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in an apparatus for processing fibrous materials, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings. Additional characteristics, aspects and advantages of the invention or of exemplary embodiments thereof will become apparent from the detailed description in combination with the claims.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 shows a schematic perspective illustration of a processing apparatus according to the invention for fibrous materials;

FIG. 2 shows a schematic perspective illustration of a pulping module of the processing apparatus according to the invention;

FIG. 3 shows a schematic perspective illustration of a grading module of the processing apparatus according to the invention;

FIG. 4 shows a slightly enlarged segment of FIG. 1 in the region of the transition between the pulping module and the grading module;

FIG. 5 shows a segment of a perspective internal view of the grading module;

FIG. 6 shows a perspective cross-sectional illustration of the grading module;

FIG. 7 shows a schematic illustration of the liquid supply for the pulping module and the grading module; and

FIGS. 8A, 8B, and 8C show detail views of a schematic illustration of the interface between the pulping module and the grading module.

DETAILED DESCRIPTION OF THE INVENTION

Referring now to the figures of the drawing in detail and first, in particular, to FIG. 1 thereof, there is shown an apparatus 100 for processing fibrous materials, in particular for pulping and grading fibrous material. In particular, the processing apparatus 100 is suitable for pulping fibrous materials with high stock densities in the HC (high consistency) range and, in particular, waste paper stock. The apparatus comprises a pulping module 10 and a grading module 50. The pulping module 10 is designed to pulp fibrous material, and the grading module 50 is designed for subsequent grading of the pulped fibrous material. Arranged between the pulping module 10 and the grading module is a heavy-component separation module 70 for separating out heavy components, such as wire, metal parts, plastic components etc., that may be present in the fibrous material, which is usually supplied in the form of bales. In addition, a feed module 30 for feeding the fibrous material, in particular in the form of bales, into the pulping module 10, a drive module 40, and a reject module 80 are provided.
An illustrative pulping module 10 with a housing 12 is illustrated in FIG. 2 . A first rotor 17 is arranged in the housing 12. The first rotor 17 comprises a rotor shaft 18, which is mounted so as to be rotatable about an axis of rotation 14 parallel to a longitudinal axis of the housing 12. Blade-type working elements 19, which can be brought into engagement with the fibrous material, are arranged circumferentially on the lateral surface of the rotor shaft 18. Here, the working elements 14 are arranged relative to the axis of rotation 14 of the rotor shaft 18, in particular in planes disposed one above the other, in which they move. A leading edge of the rotating blade-type working elements 19 can be inclined at an angle to a tangent applied to the circumference of the rotor shaft 18, the angle being, in particular, less than 45° and preferably less than 30°. In particular, the working elements 19 are disk-shaped or blade-shaped.
The housing 12 of the pulping module 10 is in the form of an upwardly open trough of U-shaped cross section extending horizontally along the axis of rotation 14. In particular, it is envisaged that the trough of the housing 12 has, in its lower region, an inner wall of partially circular, in particular semicircular, cross section. The smallest radial distance between the working elements 19 and an inner wall of the housing 12 of the pulping module 10 is about 200 mm, preferably 500 mm. By means of this trough-shaped, upwardly open configuration of the housing 12 and the large distance between the rotating working elements 19 and the upright inner wall of the housing 12, it is largely possible to prevent trapping of the introduced fibrous material between the wall of the trough and the working elements 19.
Furthermore, the pulping module 10 has a feed zone, into which the fibrous material to be treated can be introduced into the housing 12. The feed zone 22 is followed by a pulping zone. Provision can be made for the diameter of the rotor shaft 18 to be larger in the feed zone than in the pulping zone. The pulped fibrous material can be ejected, in particular, axially and/or laterally and is fed continuously to the grading module 50 after being pulped. In particular, provision can be made for the pulped fibrous material to be ejectable laterally in the region of upwardly moving working elements 19, ensuring that ejection is assisted by the moving working elements 19.
In addition, the pulping module 10 can be provided with a size reduction apparatus with various size reduction elements in order to break down components, in particular spinning components, such as cords, wires, plastic parts and foreign objects in general. These broken-down foreign objects are then removed from the fibrous material suspension and discharged by the heavy-component separation module 70. The size reduction elements can be provided both in the feed zone and in the pulping zone.
By means of the rotating rotor shaft 18, a continuous pulping process is achieved, leading to effective utilization of material and uniform and stable processing of the fibrous material. In particular, lump-free pulping of HC fibrous materials and difficult-to-pulp raw materials is possible, and this may optionally be assisted by carrying out pulping at relatively high temperatures and/or adding chemicals. The rotating working elements 19 enable mixing and kneading of the fibrous material, ensuring that the shearing forces exerted on those components of the fibrous material which still need to be separated are sufficiently high to enable the fibrous material to be pulped in an energy-efficient manner.
An illustrative grading module 50 with a housing 52 is illustrated in FIG. 3 . The housing 52 of the grading module 50 is formed separately from the housing 12 of the pulping module and can therefore be assembled and serviced independently of the housing 12 of the pulping module. In a lower region, the housing 52 comprises a screen 53, which has a multiplicity of screen openings, through which a portion of the fibrous material suspension fed to the housing 52 from the pulping module 10 can pass as accepted stock, while another portion of the fibrous material suspension is retained as reject by the screen openings. The housing 52 of the grading module 50 is in the form of an upwardly open trough of U-shaped cross section extending horizontally along a longitudinal axis, which is provided in its lower region with the screen 53, which is bent into a partially circular shape in cross section. In particular, it is envisaged that the trough of the housing 52 has, in its lower region, an inner wall of partially circular, in particular semicircular, cross section.
In addition, a second rotor 57 is arranged in the housing 52. The second rotor 57 comprises a rotor shaft 58, which is mounted so as to be rotatable about an axis of rotation 54 parallel to the longitudinal axis of the housing 52. The rotor shaft 58 is provided circumferentially with clearing elements 59 for keeping the screen 53 free and loosening the reject. In particular, the clearing elements 59 are designed as discs set obliquely relative to the axis of rotation 54 of the rotor 57 and are arranged on the rotor shaft 58 in such a way that, as the rotor 57 rotates, the fibrous material suspension and/or the reject are/is pushed backward and forward at least substantially axially. The radial distance between the clearing elements 59 and an inner wall of the housing 52 of the grading module 50 is less than 20 mm since an efficient screening action can be achieved in this way. In particular, the screen 53 can be made up of one or more appropriately bent screen plates. In this case, a plurality of zones can be provided with different screen opening cross sections.
According to the invention, the rotor shaft 18 of the first rotor 17 of the pulping module 10 and the rotor shaft 58 of the second rotor 57 of the grading module 50 are connected to one another and form a common shaft. The two rotor shafts 18, 58 can be manufactured separately and be connected to one another by a connecting element or special connecting techniques. However, provision may also be made for the rotor shaft 18 of the first rotor 17 of the pulping module 10 and the rotor shaft 58 of the second rotor 57 of the grading module 50 to be embodied in one piece in order to form the common shaft. For driving the common shaft comprising the rotor shaft 18 of the first rotor 17 and the rotor shaft 58 of the second rotor 57, the drive module 40 is provided, which comprises appropriately designed actuators or motors as well as a control device. The common shaft is driven by the drive module 40 at a maximum peripheral speed which is less than 10 m/s and preferably less than 5 m/s.
The heavy-component separation module 70 is arranged between the housing 12 of the pulping module 10 and the housing 54 of the grading module 50. As a result, heavy components are removed from the fibrous suspension before the grading module 50, thus preventing the rotor shaft 58 from being jammed by foreign objects, which would otherwise easily be the case on account of the short distance between the clearing elements 59 and the inner wall of the housing 52.
Overall, the low peripheral speed of the common shaft, which is preferably less than 5 m/s, in combination with the large distances between the rotating and the stationary surfaces in the pulping module 10 and the interposed heavy-component separation module 70 leads to low wear on the machine elements.
The fibrous material to be treated is fed to the housing 12 of the pulping module 10 by means of the feed module 30, in particular from above and orthogonally to the axis of rotation 14 or from the front and axially with respect to the axis of rotation 14. The feed module 30 is advantageously designed in such a way that a charging edge for throwing in the fibrous material bales is at a low height. As a result, only a low energy outlay is required for charging the processing apparatus 100. The feed module 30 comprises a charging hopper 32, through which the fibrous material bales are fed to the pulping module 10. The charging hopper 32 is designed in such a way that the fibrous material bales can be fed to the pulping module 10 without being broken down, such that they rest on the rotor shaft 58 and are gradually cut away by the working elements 19 of the rotor shaft 58.
The region of the transition between the pulping module 10 and the grading module 50 is illustrated in greater detail in FIG. 4 . A weir device 122 with an overflow edge is provided for the purpose of influencing the quantity of pulped fibrous material transferred from the pulping module 10 to the grading module 50. The overflow edge of the weir device 122 is adjustable in height, thus enabling the volume of pulped fibrous material discharged to be regulated.
Once the pulped fibrous material has passed the weir device 122, a further addition of liquid, in particular an addition of water is provided in order to reduce the stock density of the fibrous material suspension for passage through the heavy-component separation module 70. For this purpose, a connecting device 124, to which, for example, a water hose can be connected, is provided, in particular, in the upper region of a transport passage 125 for the fibrous material suspension. In order to achieve good mixing of the pulped fibrous material with the liquid, the liquid is fed in at a high speed, which is preferably in a range greater than 5 m/s. In addition, an impact surface inclined at a shallow angle, on which the liquid jet impinges, can be provided in the interior of the transport passage 125. The impact momentum enables the mixing of the pulped fibrous material with the liquid to be improved. After the dilution of the fibrous material suspension by the liquid fed in, the diluted fibrous material suspension then enters the heavy-component separation module 70. Owing to the dilution, the heavy components in the fibrous material suspension can settle and can be separated out as a bottom sediment in the heavy-component separation module 70.
After passing through the heavy-component separation module 70, the fibrous suspension enters the grading module 50. In order to ensure continuous transport of the fibrous material suspension from the pulping module 10 to the grading module 50, it is advantageous to match the height of the overflow edge of the weir device 122 and the height of an inflow region of the grading module 50 to one another. The inflow region of the grading module 50 is advantageously configured in such a way that the fibrous suspension can flow in below the rotor shaft 58, in particular in a region 15-20 cm below the axis of rotation 54 of the rotor shaft 58. The liquid level of the fibrous suspension is usually in a region 10-20 cm above the axis of rotation 54 of the rotor shaft 58, and the inflow region is thus below the liquid level of the fibrous suspension. As a result, turbulence during the inflow of the pulped fibrous materials into the fibrous suspension already present in the grading module 50, which may lead to loads on the rotor shaft 58, can be significantly reduced. Since, according to the invention, the rotor shaft 18 of the first rotor 17 of the pulping module 10 and the rotor shaft 58 of the second rotor 57 of the grading module 50 are connected to one another and form a common shaft, there is a reduction in vibration of the rotor shaft 18, 58 caused by turbulence of the inflowing fibrous material suspension, this reduction being significant for the stability and reliability of running of the rotor shaft 18, 58.
In particular, the screen 53 in the inflow region of the grading module 50 can have a very small height and can be provided substantially only in the bottom region of the housing 52. In another variant embodiment, it is also possible to provide for the screen 53 to be arranged only downstream of the inflow region in the grading module 50 and thus for the inflow region to be of screen-free configuration.
As illustrated in FIG. 5 , preferably a plurality of spray nozzles 128 for a liquid, in particular water, is furthermore advantageously arranged on at least one side wall of the grading module 50, in the region of a reject discharge opening 127. In particular, the spray nozzles 128 are aligned axially in the direction of the axis of rotation 54 of the rotor shaft 58. The liquid emerges from the spray nozzles 128 at a flow velocity in the range of 5-8 m/s and at a high pressure and impinges upon the reject. On account of the high velocity and the high pressure of the liquid jet, the reject is accelerated in the direction of the reject discharge opening 127, thus enabling the reject to be discharged efficiently and in a specific direction from the grading module 50. The number and dimensioning of the spray nozzles 128 can vary and, in particular, can be matched to the properties of the fibrous suspension and hence of the reject in order to achieve a high transport effect on the reject.
As illustrated in FIG. 6 , additional guide elements 129 can be arranged on the side walls of the grading module 50, the said guide elements projecting into the transport path of the fibrous suspension and, for example, being of tooth-shaped design and adjustable. By means of the guide elements 129, the transport flow of the fibrous material suspension is influenced in such a way that it is guided in a targeted way in the direction of the clearing elements 59 in order to enable efficient processing of the fibrous suspension by the action of the clearing elements 59.
Owing to the coupling of the pulping module 10 to the grading module 50 by means of the common rotor shaft, it is also possible to make the liquid supply for the pulping module 10 and the grading module 50 more efficient since the supply lines for the liquid, in particular water, can be of shorter design in respect of their length. As illustrated in FIG. 7 , the grading module 50 can comprise a production chamber 150 for the production of the accepted stock and a washing chamber 152, adjoining the latter, for the reject. However, provision may also be made for the washing chamber 152 to be arranged in the reject module 80.
The washing chamber 152 is connected to a liquid feed line 170, through which a liquid, in particular water, is introduced into the washing chamber 152. By means of the liquid, the reject is subjected to a washing process, by means of which fibrous materials still present in the reject are washed out again for further use. However, since a considerable quantity of liquid is consumed in this washing process, provision is made according to the invention to collect the liquid after the washing process, preferably in a collecting container 171 and to drain off this liquid through a liquid outlet line 173. The liquid outlet line 173 has a first liquid branch 175 for feeding into the production chamber 150, and a second liquid branch 177 for feeding into the pulping module 10. The liquid used for the washing process can thus be reused both for pulping the fibrous materials in the pulping module 10 and for grading the pulped fibrous material suspension in the grading module 50.
In a further development, provision can furthermore be made to connect the liquid outlet line 173 also to the connecting device 124 in the region of the transport passage 125 ahead of the heavy-component separation apparatus 70. Overall, it is thereby possible to significantly reduce the liquid consumption, that is to say, in particular, the water consumption, for the processing apparatus 100 according to the invention since double use of the liquid is made possible by the short transport paths.
By means of the processing apparatus 100 according to the invention, the process of pulping the fibrous material and the process of grading the fibrous material suspension are interlinked in an integrative manner.
Control of the stock density by way of stock density measurement in the accepted stock is made easier by a short control section. Rapid feedback is possible based on a short dwell time of the material. By means of an adjustable weir 93 at the end of the pulping module 10, it is possible to influence the dwell time in the pulping module 10. If the weir is moved upwards, this increases the dwell time in the pulping module 10.
This simplifies the control of the stock density in the fibrous material suspension since stock density measurement in the accepted stock in the grading module 50 and at a measuring device at the end of the pulping module 10 leads to coordinated results on account of the transfer of the pulped fibrous material to the grading module 50. In addition, the integral concept according to the invention makes it possible to achieve higher dump stock density of over 5% up to 7% in comparison with conventional OCC (old corrugated container) applications with an LC pulper or a pulping drum.
The continuous pulping process leads overall to high process stability and effective utilization of material in respect of the fibrous material. In particular, the pulping module 10 enables pulping under HC conditions, thus making it possible to achieve a suspension density in the range of 12-30%. By virtue of the “kneading” treatment of the fibrous material in the pulping module 10, the shearing forces exerted on the as yet un-pulped components are sufficiently high to enable the fibrous material to be pulped in an energy-efficient manner. A separating disk 91 is provided in the pulping module. The separating disk 91 is used to ensure that the material introduced is thoroughly processed in the pulping module. By means of lifting elements 90 provided in front of the separating disk, the suspension is conveyed over the separating disk in the direction of the outlet 92 of the pulping module 10.
By virtue of the trough-shaped, upwardly open configuration of the pulping module 10 and the large distance between the rotating and the stationary surfaces in the range of 200 mm to 500 mm, trapping of larger heavy components is prevented.
The heavy-component separation module 70 arranged between the pulping module 10 and the grading module 50 prevents jamming due to foreign objects in the grading module 50. This is of considerable importance since, owing to the process involved, a smaller distance between the rotating and stationary surfaces in the region of less than 20 mm is required in the grading module 50.
The low peripheral speed of the common shaft, in particular of less than 5 m/s, in combination with the large distances between the rotating and the stationary surfaces in the pulping module 10 and the interposed heavy-component separation module 70 leads to low wear on the machine elements.
With the processing apparatus 100 according to the invention, the coupling of the pulping module 10 to the grading module 50 by the common rotor shaft makes it possible to safely and efficiently process even very high tonnages in the region of more than 2000 tons.
The related FIGS. 8A, 8B, and 80 , show the end region of the pulping module in a three-dimensional illustration. The shaft 18 with the axis of rotation 14 is shown. The trough that forms the housing 12 has a dividing wall 94 at the end. Ahead of the dividing wall located at the end, the shaft 18 is shown, by way of example, as being provided with just one lifting element 90. Ideally, the lifting elements 90 have a working surface which lies in a plane parallel to the axis of rotation 14. However, the working surfaces may also be slightly inclined, but not by more than 30° or 20°. These working surfaces have an axial width which corresponds to 25% to 75% of the outlet 92 of the pulping module. To ensure that the pulped and diluted suspension flows from the pulping module 10 into the grading module 50 with the aid of gravity, a difference in height between the lowest position of the weir 93 and the maximum level of the suspension in the grading module 50 is required. The difference in height should be at least 35% of the shaft diameter. In the case of an exemplary embodiment with a shaft diameter of 1100 mm, that would be 385 mm. In addition, it is advantageous if the lower edge of the feed 104 into the grading module 50 is at least 10% to 20% lower than the maximum level of the suspension, based on the shaft diameter. Otherwise, it will be necessary to position the heavy-component separation apparatus 70 at a higher level, which would in turn require a larger total difference in height.
From this it follows that it is advantageous if the inlet 95 in the grading module is lowered (as already described in the text).
Additional lifting elements 90 are used at the end of the pulping module 10 to convey the suspension over the raised weir edge 123. The lifting elements are firmly connected to the rotor shaft 18. In this case, the weir edge 123 may also be significantly higher since the production rate is controlled by means of the position of the weir edge 123. By means of an adjustment that is provided, the weir edge 123 can be raised to a height of half the shaft diameter or 500 mm. The lower weir edge 123 is situated in a range of 0.3 to 1.5 times the shaft diameter vertically above the axis of rotation 14.
The lower edge 102 of the outlet of the pulping module 50 is depicted in FIG. 8C. This lower edge 102 is situated at a vertical height 103 above the axis of rotation 14, 54 of the pulping module 10 and the grading module 50. The lower edge 104 of the feed into the grading module, also referred to as the grading module inlet 95, is vertically below the axis of rotation 54, 14. The vertical distance below the axis of rotation 14, 54 is denoted by 105.
In the illustration, the grading module 50 is provided with a dividing wall 96 on the side facing the pulping module 10. In the assembled form, the dividing walls 94 and 96 are arranged axially adjacent.
The following is a summary list of reference numerals and the corresponding structure used in the above description of the invention:

- 100 Processing apparatus
- 10 Pulping module
- 12 Housing
- 14 Axis of rotation
- 17 Rotor
- 18 Rotor shaft
- 19 Working elements
- 30 Feed module
- 32 Charging hopper
- 40 Drive module
- 50 Grading module
- 52 Housing
- 53 Screen
- 54 Axis of rotation
- 57 Rotor
- 58 Rotor shaft
- 59 Clearing element
- 70 Heavy-component separation apparatus
- 80 Reject module
- 90 Lifting element
- 91 Separating disk
- 92 Outlet of pulping module
- 93 Weir, adjustable
- 94 Dividing wall at end of pulping module 10
- 95 Inlet of grading module
- 96 Inlet-side dividing wall of grading module 50
- 102 Lower edge of the outlet of the pulping module
- 103 Vertical height above axis of rotation
- 104 Lower edge of feed
- 105 Vertical distance from the axis of rotation
- 122 Weir device
- 123 Weir edge, lower weir edge
- 124 Connecting device (dilution)
- 125 Transport passage
- 127 Reject discharge opening
- 128 Spray nozzle
- 129 Guide element
- 150 Production chamber
- 152 Washing chamber
- 170 Liquid feed line
- 171 Collecting container
- 173 Liquid outlet line
- 175 First liquid branch
- 177 Second liquid branch

Claims

1. An apparatus for processing fibrous materials, the apparatus comprising:

a pulping module for pulping fibrous material into a fibrous material suspension, said pulping module having a pulping module housing and a first rotor with a rotor shaft arranged in said pulping module housing;

a grading module coupled to said pulping module and configured for subsequent grading of the pulped fibrous material suspension, said grading module having a grading module housing with a screen for separating the fibrous material suspension into accepted stock and reject, and a second rotor with a rotor shaft arranged in said grading module housing; and

said rotor shaft of said first rotor of said pulping module and said rotor shaft of said second rotor of said grading module being connected to one another and forming a common shaft.

2. The apparatus according to claim 1, further comprising a heavy-component separation module arranged between said pulping module and said grading module.

3. The apparatus according to claim 1, wherein:

said pulping module housing comprises a trough formed with a base of partially circular cross section in a lower region extending horizontally along a longitudinal axis;

said first rotor comprises said rotor shaft rotatably mounted about an axis of rotation parallel to the longitudinal axis of said pulping module housing and working elements arranged circumferentially on said rotor shaft and disposed to be brought into engagement with the fibrous material;

said grading module housing comprises a trough extending horizontally along a longitudinal axis and having a base provided in a lower region thereof with a screen that is bent into a partially circular shape in cross section; and

said second rotor comprises a rotor shaft rotatably mounted about an axis of rotation parallel to the longitudinal axis of said grading module housing and clearing elements arranged circumferentially on said rotor shaft and disposed for keeping said screen free and for loosening the reject.

4. The apparatus according to claim 3, wherein said trough of said pulping module housing and said trough of said grading module housing have, at least in a lower region thereof, an inner wall with a partially circular cross section.

5. The apparatus according to claim 4, wherein said inner wall has a semicircular.

6. The apparatus according to claim 1, wherein said rotor shaft of said first rotor of said pulping module and said rotor shaft of said second rotor of said grading module are connected to one another and form a common shaft, and said trough of said pulping module adjoins said trough of said grading module.

7. The apparatus according to claim 1, wherein said rotor shaft of said first rotor of said pulping module and said rotor shaft of said second rotor of said grading module are formed in one piece to form said common shaft.

8. The apparatus according to claim 1, further comprising a drive module for controlling and driving said common shaft formed of said rotor shaft of said first rotor of said pulping module and said rotor shaft of said second rotor of said grading module.

9. The apparatus according to claim 8, wherein said common shaft is configured to be driven at a maximum peripheral speed of less than 10 m/s.

10. The apparatus according to claim 9, wherein said common shaft is configured to be driven at a maximum peripheral speed of less than 5 m/s.

11. The apparatus according to claim 1, further comprising a heavy-component separation module arranged between said pulping module and said grading module, next to said pulping module housing and next to said grading module housing.

12. The apparatus according to claim 3, wherein a smallest radial distance between said working elements and an inner wall of said pulping module housing is about 200 mm, and wherein a radial distance between said clearing elements and an inner wall of said grading module housing is less than 20 mm.

13. The apparatus according to claim 12, wherein the smallest radial distance between said working elements and the inner wall of said pulping module housing is about 500 mm.

14. The apparatus according to claim 1, wherein said grading module is formed with an inflow region configured for the fibrous suspension to flow in below said rotor shaft.

15. The apparatus according to claim 14, wherein said grading module is formed for the fibrous suspension to flow in in a region 15-20 cm below the axis of rotation of the rotor shaft.

16. The apparatus according to claim 14, wherein said screen has a very small height in said inflow region of said grading module and is arranged substantially only in a lower bottom region, or said inflow region has a screen-less configuration and said screen is arranged only downstream of said inflow region in said grading module.

17. The apparatus according to claim 1, wherein said pulping module is formed with an outlet having a lower edge, being a weir edge, and said weir edge is arranged in a range of 0.3 to 1.5 times a shaft diameter of said rotor shaft in said pulping module vertically above the axis of rotation in said pulping module.

18. The apparatus according to claim 16, wherein said rotor shaft of said pulping module has at least one lifting element for conveying fibrous suspension out of said pulping module.

19. The apparatus according to claim 16, wherein a vertical difference in height between said outlet of said pulping module and said inlet of said grading module is formed to ensure that the flow of fibrous suspension from said pulping module to said screen module via said heavy-component separation apparatus takes place without an interposition of a pump.

20. The apparatus according to claim 1, configured for processing fibrous material with high stock densities in a high consistency (HC) range.