WO2000029183A1

WO2000029183A1 - Granulate and method and device for the production thereof

Info

Publication number: WO2000029183A1
Application number: PCT/EP1999/009741
Authority: WO
Inventors: Gerhard Jakwerth
Original assignee: Flz Faserlogistikzentrum Gmbh
Priority date: 1998-11-12
Filing date: 1999-11-12
Publication date: 2000-05-25
Also published as: DE19956164A1; EP1128941A1; HUP0104341A2; CZ20011634A3; BR9916604A; WO2000029183A8; ID30227A; CA2350760A1; PL348146A1; AU1975800A; DE29920772U1; SK6482001A3

Abstract

The invention relates to a granulate and a method and a device for the production thereof. The aim of the invention is to provide a granulate on the basis of regenerative raw materials which is suitable as a material for injection molding and which is widely variable with respect to its mechanical and other physical properties due to the introduction of additives. The inventive method provides a means for producing the granulate without specifically pre-treating the plant parts used. A device is provided for carrying out the inventive method which device may consist of a pre-granulator and a final granulator or only of a pre-granulator. An especially clean-cut granulate can be obtained by the various configurations of the final granulator which can be equipped with counter-rotating matrices or with matrices that rotate one inside the other.

Description

Granules and method and device for its

Manufacturing

description

The invention relates to a granulate and a method and a device for its production according to the preambles of claims 1, 11 and 21.

It is known that fiber composite materials are increasingly used in the automotive industry for the production of interior lining parts. The use of natural vegetable fibers to reinforce plastics instead of conventional glass fibers offers an inexpensive and environmentally friendly alternative.

Bast, hard and leaf fibers such as flax, hemp, jute, sisal, ramie, yucca, wood, curano fibers and fibers of the banana tree are known as suitable natural fibers for reinforcing plastics and biopolymers. However, various fiber pulping treatments have to be carried out, such as the mechanical processing of the fibers in the swing arm, where the fibers are freed from wood and cockroaches, or the pretreatment of the fibers in the melt so that they are suitable for mixing for further processing. It is known this To incorporate natural fibers in the form of nonwovens into the plastic, the starting material for the composite material being produced from two different types of fiber, the polypropylene fiber serving as the matrix and the reinforcing fiber, for example flax fiber in the form of pressed bales, tapes or rovings.

Furthermore, it is known to use plastic technology to produce fiber granules from plastic, in order to then either bring them together with the textile mats made of natural fibers (DE 4412636) or in the extruder together with the non-granulated natural fiber components in the form of rovings or tapes to form composite materials to process.

When using extruders for plasticizing the plastic fibers, there is generally the disadvantage that this additional process step of extrusion requires such high investment and energy costs that the products produced in this way can no longer be used economically. In addition, the fibers used must be subjected to an additional temperature load at least at the level of the melting point of the plastic content present, which in turn leads to an increased odor load and lower strength values. In addition, the fibers used are shortened to a fiber length that cannot be directly influenced, with a large amount of scatter in the extruder, which leads to considerable segregation of the fiber content when parts with different wall thicknesses are sprayed. Since some types of fiber tend to break when dry, the use of natural fibers is in Large-scale production in the well-known feed types such as rovings, strips and piles in the extruders is very limited. Another disadvantage of the extruder in the processing of the natural fibers is that the fiber components in the screw can no longer be compensated for in the event of malfunctions in the feed area, which is caused by the process of the first-in / first-out principle of the extruder.

The invention is therefore based on the object of offering a granulate based on renewable raw materials which is suitable as an injection molding material and which can be varied within wide limits with the addition of additives with regard to its mechanical and further physical properties.

Furthermore, the invention has for its object to provide a method and an apparatus with which the production of the granules is possible without the plant parts used having to be pretreated.

The problem is solved with the features of claims 1, 11 and 21.

Advantageous further developments are specified in the subclaims.

Thus, according to claim 2, granules are possible which contain a wide variety of additives such as adhesion promoters, flame retardants, further fillers, dyes and antibiotic agents which can be incorporated by the process according to the invention. The development according to claim 3 to claim 5 enables the addition of thermoplastic materials, polypropylene and polyethylene in particular being advantageously used here. The thermoplastic materials can also be contained in large amounts in the granulate as recycled plastics.

The embodiment according to claim 6 specifies a granulate composition which is characterized by the use of different plant fiber mixtures. The advantage lies in a further possibility of influencing the physical properties of the granulate according to the invention, such as, for example, the specific weight and the thermal insulation.

According to the development according to claim 7, flax, hemp, sisal, jute and wood fibers are particularly suitable.

Particularly advantageous mechanical properties are achieved if the plant fibers are brought into a fibrillar state by appropriate management of the method according to the invention, as shown in the embodiment of claim 8.

Surprisingly, according to the development of claim 9, it has also been shown that the granules according to the invention can contain up to 98% plant fibers, the binding of the plant fibers to one another being achievable via the additives contained. This means that particularly light granules can be obtained here. In the embodiment according to claim 10, a granular composition based on the vegetable fiber using thermoplastic materials is specified.

A major advantage of the method according to the invention is entered in the further development according to claim 12, in which the starting mixtures used as plant parts do not have to be pretreated, but can be subjected to the method immediately in non-or even roughly comminuted form.

According to the embodiment of claim 13, known additives such as dyes, adhesives, flame retardants, fillers and antibiotic agents can be added so that the granules obtained can be used directly, for example in an injection molding process. As a result, the finished products are created without further post-processing.

The selection of the granulation parameters in accordance with the embodiment of claim 14, in combination with the addition of water, enables advantageous shredding of the plant parts down to a fibrillar size. In this case, it makes sense to carry out the granulation in two stages in accordance with the development of claim 15, where between the first and the second granulation stage. other additives can advantageously be added.

According to the invention, a pressing pressure is advantageously generated by the configurations according to FIG Claims 16 to 18 in connection with the formation of the press channels of the dies according to claim 30.

The method according to the invention advantageously allows the addition of thermoplastic substances both in the first granulation stage and before the second granulation stage to be made possible by the configuration according to claim 19.

The size of the pressure can be regulated according to the embodiment of claim 20 by changing the distance between the counter rotating dies or between die and Koller.

A particular advantage of this method is that all natural fibers and their mixtures can be used in connection with the device according to claim 21. By using a pre- and a final pelletizer, no special fiber digestion processes are to be used, as a result of which all known natural fibers are available for processing.

With the developments according to the features of claim 22 in conjunction with claims 23,

24 and 30 pre-granules can be produced inexpensively, which contain a high proportion of vegetable fiber materials.

A particularly clean granulate that for

Further processing in the injection molding machine is suitable because of the particularly advantageous

Training of the final pelletizer according to the claims

25 and 28. Additions regarding the minimum distance and the die diameter as well as the clearing devices are shown in claims 26, 27 and 29.

With the granulate produced by the method and the device according to the invention, e.g. Composites are produced that are light in weight and that meet the requirements for mechanical properties in terms of tensile strength, bending strength, susceptibility to breakage and cracking and are also very environmentally friendly because they can be recycled. Such products can be used to e.g. the entire interior, including headlining, door trim, side panels inside and outside, seat components, instrument panels and columns, etc. to manufacture a vehicle entirely from natural fiber materials.

Further advantages of this invention lie in the simple method of processing the plant material and the possibility of using all types of plant material and their mixtures and the saving of essential process steps of the conventional technology, with constant and improved possible uses of the granules. With the method according to the invention, the fibers used can be used largely untreated, regardless of whether they are long fibers or short fibers or directly straw. There is also no need to plasticize the fibers using extruder technology. The highly concentrated granules produced can be mixed with other constituents, for example plastics, further processed into products in an injection molding process. The invention will be explained in more detail below using exemplary embodiments.

Show it

1 shows a combination of pre- and end pelletizers in a schematic sectional view;

2 shows a representation of the pressure distribution in the case of various Koller profiles, FIG. 3 shows a configuration of the press channels a) in the case of compressible starting material b) in the case of highly compressible starting material c) in the case of highly concentrated fiber granules,

4 shows a schematic diagram of the end granulator with matrices running into one another,

5 is a detailed view of the matrices running together,

6 shows a sectional view of the matrices running into one another with drive, FIG. 7 shows a construction of the end pelletizer with matrices running into one another,

8 shows a detailed view of the matrices running into one another with openings and press channels,

9 shows a construction of the end granulator with matrices running side by side,

10 is a sectional view of the matrices running against each other,

Fig. 11 is a schematic representation of the end pelletizer with opposing dies and Fig. 12 is a detailed view of the matrices running against each other with openings and press channels.

The device according to the invention according to FIG. 1 consists of a pre-granulation unit 216 and a final granulator 211. The pre-granulation unit 216 has feeders 201, 202 and 203, via which the starting material to be processed, in particular pourable material, is fed to a mixing chamber 215. All soft starting materials, such as the plant part mixtures and also individual plant types, film granules made from recycled materials, are fed into the mixing space via the feed 203. The feeders 201 and 202 are provided to the hard starting materials such as dyes, coupling agents or fillers, for. B. titanium dioxide or all metals and their alloys. High-pressure nozzles 204 and 205 are arranged along the circumference of the pre-granulation unit 216 in such a way that they protrude into the mixing chamber 215 and allow water or steam to be introduced there. The water entered can contain various additives, such as anti-mold agents, odors and bacterial infections or flame retardants. For design reasons, the high-pressure nozzle 205 is designed as an angle nozzle.

The introduced starting materials meet a baffle plate 206 which is shaped as a pointed cone. The resulting swirling mixes the feed materials better. Arranged below the baffle plate 206 is a flat die press known per se, which consists of a perforated die 209 and a roller 208 which can be rolled on it and which is secured with a lock nut 207. The material in the mixing room 215 is here by means of the roller 208 through pressing channels 217 of the die matrix 209. In this case, both the press channels 217 and the surface of the roller 208 have an inventive design. A sawtooth profile is applied to the surface of the roller 208. The higher the proportion of plant fiber in the starting material, the steeper and deeper the flanks of the sawtooth profile are. This sawtooth profile causes the material to be subjected to even greater shear stress due to high shear, and is therefore more intensively mixed and crushed. The pressure build-up and the pressure distribution of a sawtooth profiling in comparison to the known symmetrical profilings is shown in FIG. 2. This clearly shows that a lower pressure builds up when the profiling is symmetrical and weak (FIG. 2, pressure curve la). The pressure increases with more pronounced symmetrical profiling (FIG. 2, pressure curve 2a) and is highest with sawtooth profiling (FIG. 2, pressure curve 3a).

The Koller 208 rolls on the die die 209, which is equipped with the press channels 217, the number and diameter of which significantly determine the specific design of the granules according to the invention. The geometric shape of the pressing channels 217 also has an influence on the heat development and thus on the temperature and on the density of the granules to be produced. 3a, b and c show various geometrical configurations of the press channels 217 according to the invention.

A reproducible good quality with different starting materials is achieved by the pressing channels 217 next to their input side In addition, expansion slots have relief slots 218 on the output side. According to the invention, these relief slots 218 have regular and symmetrical shapes, as can be seen in FIGS. 3a, b or c. To introduce the relief slots 218, the pressure channel 217 is crimped on the output side by means of a stamp made of tool steel. The longer relief slots 218 according to FIG. 3 c are used in the case of larger proportions of vegetable fibers in the starting material.

A clearing device 210 for stripping off the granules that have passed is arranged below the die matrix 209 and can be adjusted to the position of the roller 208. This granulate can now be removed for further processing. However, if the proportion of the plant constituents in the starting mixture is more than 60%, the quality of the granules produced with the pre-granulator 216 can be significantly improved by a downstream end granulator 211. The pre-granules are therefore transferred immediately or after further mixing, if necessary, in a mixing chamber (not shown separately) with other additives via a pre-granulate outlet 213 into the final granulator 211.

According to FIG. 1, the end granulator 211 contains an arrangement of counter-rotating, cylinder-shaped matrices 1 and 2, as also shown in FIGS. 9, 10, 11 and 12, which are arranged next to one another on a machine table 15. The die 1 is rotated by a drive 6, the movement of which is transmitted via a belt 7, a belt wheel 8 to a receiving part 4, which lies in a ball bearing 3 and in turn holds the die 1. With an engine mount 25, the belt 7 can be tensioned, which is protected with a corresponding covering 9. The second subordinate die 2 is arranged radially displaceably on a dovetail guide 28. The die 2 can be moved in the direction of the die 1 with a hydraulic adjusting and pressure cylinder 10, which is attached to a height-adjustable support bracket 13 via a joint 12. This movement is limited by a stop 23. When the two dies 1 and 2 approach sufficiently, the die 2 is also rotated by the die 1 via a hard rubber surface 11 arranged on the end face. With the adjustable clearing combs 17 arranged inside the dies 1 and 2, the material pressed through is separated off and conveyed by broaching augers 19 into a granulate discharge housing 16 by means of the electric drive 18. This is mounted with an inner die cover housing 24 on a fixed shaft 27, with a counter-holder 26 being arranged at the other end. The matrices 1 and 2 are covered by the housing 22, on which hinged covers are attached by means of hinges. The granulate inlet housing 21 is arranged on the housing 22. The directions of rotation of dies 1 and 2 are marked with arrows. If the die 2 is in a raised position, removed from the die 1, it assumes a position 20. A hydraulic unit 14 for controlling the lateral movement of the die 2 is arranged in the machine table 15.

FIGS. 4, 5, 6 and 7 show a further embodiment variant of the end granulator 211, in which, as described below, ring matrices which run into one another according to the invention are arranged. The centerpiece of the end granulator 211 are the cylindrical ring matrices 101 and 102 arranged one inside the other (FIG. 8), the throughput quantities of the starting material being able to be influenced via the width of the ring matrices 101 and 102. An outer larger driven ring die 101 is mounted with its receiving part 4 in a ball bearing 3 and is driven electrically or hydraulically by a drive 6 by a high-performance belt 107 or a high-performance belt wheel 108. In the interior of the outer ring die 101, the small inner ring die 102 is rotatably arranged on a swivel bar 111, the directions of rotation of the ring die 101 and 102 being indicated by arrows. The selected diameter of the smaller ring die 102 depends on the fiber content of the material to be granulated or of the pre-granulate. The diameter ratio of the ring matrices 101 and 102 determines the pressure range. With a large ring die 101 and a small ring die 102, for example, a small pressure area with high pressure is generated. In principle, the diameter of the smaller ring die 102 can be one third to two thirds of the diameter of the large ring die 101. The diameter size can be adapted according to the invention without great effort and is necessary in order to be able to produce granules with different fiber contents and additives. The swivel beam 111 of the ring die 102 is fastened at the rear end with a joint 112 to an element 113 which, depending on the state of wear or wear of the ring die 102, serves to gradate the height and align it with the center of the joint. With a hydraulic adjusting and pressure cylinder 10, the contact pressure of the inner ring die 102 is generated or this ring die 102 is brought into the waiting or assembly position. The mobility of the swivel beam 111 is limited by a Fixed stop 23, which secures the minimum gap between the ring matrices 101 and 102 and prevents the metal matrices 101 and 102 from rubbing against one another. In the event of an overload or solid bodies in the pre-granulate, the ring die 102 can spring back due to the hydraulics and would then take the position 120 and thus protect the system from destruction.

To detach the granules, an adjustable and adjustable clearing comb 17 is attached below the outer ring die 101, while the granules emerging in the interior of the ring die 102 are conveyed into the granule outlet housing 16 by means of the auger 19 moved by the electric drive 118. The filling material, e.g. the pre-granulate passes through the granulate inlet housing 21 with housing hinge 122 into the area above the ring die 102. The circumferential outer ring die 101 and its drive device are protected by a housing covering 9, the front covers of which are designed to be pivotable.

The method according to the invention is to be explained in more detail below:

Flax straw, jute straw, hemp straw as well as flax, jute, hemp and sisal fibers, other parts of plants and their mixtures are used as raw materials. These plant parts are cut, corrugated and dried for harvesting, as well as processed into a bale shape. It is also conceivable to use fine, medium and coarse structured cockroaches as well as rovings or tapes made from mixtures of the fiber types mentioned. The straw is dry and good stored ventilated, storage is easily possible for a good 3 years.

In one embodiment, the base material, flywheel or plant row pressed into bales is used. A residual bar content of up to 10 percent by weight is possible. These impurities do not interfere, but act like fillers. Small stones that would destroy the extruder using conventional technology do not hinder this process. The plant parts are then fed to a known bale opener. When using different fibers, such as flax, sisal, jute, these are each processed in a so-called bale cradle opener, so that the fiber mixture can be created by weighing according to certain proportions by weight. All conditions are possible and are only determined by the following areas of application. Although the plant parts can generally be re-used depending on the application, the components are usually shortened to a maximum length of 50 mm using two cutting machines or alternatively with an opening roller to the desired fiber length of maximum 50 mm. In the further process, the starting material is passed over the heavy parts separator and metal separator in order to remove large impurities. In the multi-mixer, vigorous mixing of the plant components supplied takes place over several stages. A mixture of, for example, 30% flax, 30% sisal and 32% jute fibers is now pneumatically fed to a pre-granulation unit 216 in order to reduce the fiber mixture to 5 mm in diameter at a compression ratio which is formed from the ratio of the length of the compression channels 217 to the diameter of the Pre-granulate press channels 217 of 1: 6 at 120 ° C to 130 ° C. At the same time, the fiber mixture is sprayed with a water mist, which contains agents to prevent the formation of odors or mold and against bacterial attack. It is also possible, depending on the type of use of the later granulate, to look at thermoplastic materials such as polypropylene in order to obtain granules for a wide variety of applications. Thermoplastic materials can be added in powder form, as well as in fiber or granulate form.

Advantageously, a portion of natural fibers can also be replaced by refurbished recycling material, e.g. was obtained from the recycling of used composites.

The pre-granulation works according to the known principle of press agglomeration, so that the pre-comminuted mixture is applied to the perforated die 209 provided with press channels 217 and the fiber material is pressed through the press channels 217 of the perforated die 209 by rolling over the roller 208. Depending on a special supply of the mixture to the die matrix 209 and the design of the press channels 217, the granulation process stabilizes after 15 minutes and a dry granulate which can be easily metered is formed. The pre-granules pressed through the press channels 217 of the die matrix 209 are gravimetrically mixed in a further mixing chamber with a color masterbatch and continuously dispensed into the final granulator 211 in a metered manner. It is essential to the invention that, depending on the diameter, the shape and length of the pressing channels 217 on the die matrix 209 in the pre-granulating unit 216 or the final granulator 211 different granules are obtained. The press ratio is 1: 8 for a diameter of the press channels 217 of 4 mm and 1:10 for a diameter of 3 mm in the case of 92% pre-granulate and 8% color masterbatch. The throughput is increased by profiling the surface of the roller 208 and the number of press channels 217 on the punch die 209. The choice of the ratio of the closed area to the open area on the perforated die 209 and the regulation of the gap width between the surface of the roller 208 and the perforated die 209 make it possible to process a wide variety of fiber mixtures.

Granules leaving the final granulator 211 are filled, cooled, welded airtight and then handed over to the user. It can now e.g. B. be fed directly to the spraying machine via a gravimetric metering device in the desired ratio with a pure plastic granulate.

In a further exemplary embodiment, the straw cut to 3 to 5 mm in the pre-granulation unit 216 is injected with water spray with dissolved additives against mold formation, against bacterial attack and odor formation at a press ratio of 1: 6 at 120 ° C. to 130 ° C. as described pre-granulated, the pre-granulated material having a pellet diameter of 6 mm. 35 percent by weight of the pre-granules are then mixed with 35 percent by weight of a first plastic granulate and 30 percent by weight of a second plastic granulate. The thickness of the dies 1 and 2 of the end granulator 211 is 30 mm in the area of the press channels 217, the diameter the dies 1 and 2 is 440 mm and is provided with press channels 217 of 3 mm diameter, relief notches 218 being designed on the press channels 217 and a press ratio of 1: 8 having to be maintained.

Reference list

Die die ball bearing mounting part

Drive, electric or hydraulic Belt pulley Housing cladding Hydraulic adjusting and pressure cylinder Hard rubber surface Articulation Height-adjustable support bracket Hydraulic unit Machine table Granule discharge housing Clearing comb Electric drive Clearing auger Position Granulate inlet housing Housing Fixed stop Inner die cover housing Motor mount Bracket Fixed shaft Dovetail guide 101 ring die

102 ring die

103 104 105

106

107 high performance belts

108 high performance pulley

109 110

111 swivel beams

112

113 Element for gradation

114 115

116

117

118 electric drive for auger

119 120 Position of die 1 in the raised position

121

122 housing hinge

201 feed

202 feeder

203 feed 204 high pressure nozzles

205 high pressure nozzles

206 baffle

207 lock nut

208 Koller 209 punch die

210 clearing device

211 final pelletizer 212

213 Pre-granulate outlet 214

215 mixing room

216 pre-granulation unit

217 press channel

218 relief slots

Claims

claims

Granules consisting of fibers and (binders), characterized in that the granules contain plant fibers and additives.

Granules according to claim 1, characterized in that adhesion promoters and / or

Flame retardants and / or fillers and / or

Dyes and / or antibiotic agents are included.

3. Granules according to claim 1 or 2, characterized in that thermoplastic materials are included.

4. Granules according to one of claims 1 to 3, characterized in that thermoplastic polymers are contained.

5. Granules according to one of claims 1 to 4, characterized in that polypropylene and / or polyethylene are included.

6. Granules according to one of claims 1 to 5, characterized in that

Plant fiber mixtures of different plants are included.

Granules according to one of claims 1 to 6, characterized in that,

Flax, sisal and / or jute fibers are included.

Granules according to one of claims 1 to 7, characterized in that the plant fibers are contained in the fibrillar state.

9. Granules according to one of claims 1 to 8, characterized in that

92 to 98% vegetable fibers and 2 to 8% additives are included.

10. Granules according to one of claims 1 to 8, characterized in that 1 to 80% thermoplastic materials,

2 to 8% additives and 12 to 97% vegetable fibers are included.

11. A process for the production of granules from plant parts by press agglomeration, characterized in that Plant parts and additives in the presence of

Water and elevated temperature are mixed in seconds and pressed under pressure through a perforated die, followed by comminution of the mass pressed through the perforated die.

12. The method according to claim 11, characterized in that the plant parts are used in a non-pretreated, not comminuted and / or comminuted form.

13. The method according to claim 11 or 12, characterized in that

Additives such as dyes, adhesives, flame retardants, fillers and / or antibiotic agents are added.

14. The method according to any one of claims 11 to 13, characterized in that the granulation at a process pressure of 15 to 200 bar and at a temperature between 0 and

150 ° C is carried out.

15. The method according to any one of claims 11 to 14, characterized in that the granulation is carried out in two stages, wherein in the first stage, pre-granulation is carried out in the presence of water vapor and optionally additives, and then a pre-granulate is fed to a mixer, optionally further additives are added, and the mixture is then subjected to final granulation.

16. The method according to any one of claims 11 to 15, characterized in that the pressing pressure is generated by the rolling movement of a roller on the die surface.

17. The method according to any one of claims 11 to 15, characterized in that the pressure is generated by moving against one another at least two dies.

18. The method according to any one of claims 11 to 15, characterized in that the pressure is generated by means of an extruder screw.

19. The method according to any one of claims 11 to 18, characterized in that in the first stage and / or before the second stage, thermoplastic materials such as polypropylene and / or polyethylene are added.

20. The method according to any one of claims 11 to 19, characterized in that the pressure is controlled by changing the distance between the matrices moving against each other.

21. Device for producing granules from plant parts, consisting of a Vorgranuliereinheit (216) and _'a downstream Endgranuliereinheit (211).

22. The apparatus according to claim 21, characterized in that the pre-granulating unit (216) consists of a flat die press known per se and from a mixing space (215) arranged above it, wherein

Water outlet nozzles (204, 205) and feeders

(201, 202, 203) protrude into the mixing space (215), a baffle plate (206) arranged in the mixing space (215) is fastened above a pan (208), and one below a perforated die (209)

Clearing device (10) and a pre-granulate outlet (13) are arranged.

23. The apparatus according to claim 21, characterized in that a further mixing chamber is arranged between the pre-granulating unit (216) and the final granulator (211).

24. The device according to claim 21 to 23, characterized in that the surface of the pan (8) is designed as a sawtooth profile.

25. The device according to claim 21, characterized in that the end pelletizer (211) consists of a ring die press known per se, and instead of the inner-running mill, a cylindrical ring die (102) within an outer cylindrical ring die (101) is rotatably arranged so that the inner ring die (102) presses against the outer ring die (101).

26. The apparatus of claim 21 and 25, characterized in that the diameter of the ring die (102) is one third to two thirds of the diameter of the ring die

(101) is.

27. The apparatus according to claim 21, 25 and 26, characterized in that below the ring die (101) an adjustable and adjustable clearing comb (17) and inside the

Matrix (102) a broaching screw (19) are arranged.

28. The apparatus according to claim 21, characterized in that the end granulator (211) contains two counter-rotating cylindrical dies (1) and (2), the die (1) being connected to a drive (6) and the movable die (2) is arranged at a minimum distance from the die (1).

29. The device according to claim 21, 24 to 28, characterized in that a minimum stop stood between the die (1, 101) and die (2, 102) is adjustable by a fixed stop (23).

30. The device according to claim 21 to 29, characterized in that the perforated die (9) and / or the ring dies (101, 102) and / or the dies (1, 2) are provided with press channels (217), the input side of the Press channels (217) widenings and / or regular, symmetrically shaped relief slots (218) are provided on the output side.

31. The device according to claim 21, characterized in that the device consists only of the pre-granulation unit (16). .