Disc agglomerator with direct connection

Abstract

The invention relates to a system for agglomerating and comminuting recycled plastic, comprising an agglomerator which is designed to receive plastic waste and form same into elongated pin-shaped or sausage-shaped agglomerates in a pasty state and which is designed in the form of a disc agglomerator, comprising two discs which are profiled on the mutually facing surfaces thereof, can be moved relative to each other, and are arranged parallel and at a distance to each other and between which a disc intermediate area is formed. The agglomerator has an inlet opening for the recycled plastic, said opening leading into the central region of the disc intermediate area, and an outlet opening for the agglomerates in the outer circumference of the disc intermediate area. According to the invention, a housing runs about the exterior of the discs of the disc agglomerator in an annular manner and has a housing opening which adjoins a conveyor line, wherein a rotating disc of the disc agglomerator is designed to have a conveying effect so as to act on the agglomerates and guide same into the conveyor line under pressure, and the conveyor line leads to a device for further processing the agglomerates.

Description

[0001] "Disc agglomerator with direct connection"

[0002] Description:

[0003] The invention relates to a system according to the preamble of claim 1.

[0004] Generic systems are known from practice.

[0005] For example, EP 2 817 131 B1 discloses a disc agglomerator in which plastic waste is processed into elongated strands of material, which are then crushed to form small particles. For the purposes of this proposal, both the plastic waste to be recycled in the disc agglomerator and the agglomerates produced in the disc agglomerator are referred to as plastic recyclate.

[0006] These particles can later be used as raw materials in the plastics processing industry, for example, they can be further processed in an extruder.

[0007] DE 41 18 858 discloses a disc agglomerator in which the agglomerates are fed directly into the inlet of an extruder. The extruder is located at a distance below the lower peripheral section of the disc agglomerator, and the agglomerates fall freely from the disc agglomerator through a chute-like inlet located above the extruder. The pre-agglomeration, pre-compression, and pre-compacting functions upstream of the extruder take place in the disc agglomerator itself.

[0008] The invention is based on the object of improving a generic plant in such a way that it enables the processing of plastic waste with low energy and economic expenditure.

[0009] This object is achieved by a system according to claim 1. Advantageous embodiments are described in the subclaims.

[0010] In other words, the invention proposes that the agglomerated material strands emerging from the outlet opening of the disc agglomerator and directed radially outwards are transferred directly from the disc agglomerator into a conveyor device and not just into its inlet. A housing runs in a ring around the outside of the two discs of the disc agglomerator and has a housing opening. Connected to this is a conveyor line leading to a downstream processing device, e.g. an extruder. The agglomerates are therefore not first collected and temporarily stored, where they cool down, but are processed directly, so that they do not have to be brought back to the desired processing temperature for further processing. The energy expenditure for possiblyThe proposed system can reduce the time required to first cool the agglomerates to prevent them from sticking together and then heat them up to processing temperature. The agglomerates are present as elongated strands of material when they emerge from the disc agglomerator radially outward between the two discs. Because their temperature gives them a slightly sticky surface, they tend to form a heap of irregularly arranged, adhering strands of material that cannot be drawn into the housing of a conveyor or extruder screw. Furthermore, this heap forms a barrier and prevents the inflow of further agglomerates within a short period of time.

[0011] The two discs of the disc agglomerator are movable relative to one another, e.g., through different speeds and / or directions of rotation if both discs are rotatable, or by one disc, referred to as the stator, being stationary and the other, referred to as the rotor, being rotationally driven. The invention is based on the idea that either the kneading bars on the rotor disc of the disc agglomerator or any present conveying-effective comminution tools, which serve to comminute the elongated agglomerates, convey the agglomerates to the outlet opening, additionally assisted by the pressure resulting from the inflowing material in the space between the discs and by the centrifugal force acting on the agglomerates due to a rotating disc of the disc agglomerator.

[0012] In one embodiment, the conveying efficiency of a rotating disc of the disc agglomerator can be achieved by the design of its pre-defined elements, e.g., by appropriately shaping and arranging the kneading bars and / or comminution tools. In another embodiment, the disc can have conveying elements, i.e., specially designed elements that serve solely to convey material and that effect or support the conveying efficiency of the disc.

[0013] In one embodiment of the system, the agglomerates can be crushed into small particles. In a disc agglomerator, the outlet opening is either the gap opening resulting from the distance between the two discs, i.e., an annular slot or gap between the two discs corresponding to the disc circumference, or an opening in a housing surrounding the two discs. For example, the material strands can be crushed using a ring crusher, i.e., with several crushing tools arranged on a circular line and closely spaced radially inside or outside the outlet opening, and thus downstream of the disc agglomerator in the flow direction of the recycled plastic.The agglomerated material strands emerging from the outlet opening of the disc agglomerator are accordingly forced against the crushing tools and are cut into shorter pieces, namely the desired small particles.

[0014] This eliminates the need to transport the material strands through an additional conveyor system to a shredding device located at a distance from the disc agglomerator. The energy required for this conveyor system can therefore be saved, in addition to the energy savings already achieved according to the proposed system. Furthermore, the relatively softer material strands, which have not yet cooled down, are shredded directly at the exit of the disc agglomerator, so that the energy required for this shredding is lower than the energy required for later shredding of the same, but cooled and thus harder, material strands, which represents a further energy advantage. Finally, a particularly compact design of the system is also achieved.

[0015] The crushing tools can, for example, be arranged directly on a disc of the disc agglomerator, or they can be mounted on a specially provided ring, which is therefore referred to as a crushing ring.

[0016] In one embodiment of the system, the shredding ring can be adjustable in the axial direction of the ring agglomerator, i.e. essentially transversely to the plane of the two discs, so that it opens or closes the annular outlet opening to varying degrees in the axial direction, i.e. can make the gap width of the outlet opening narrower or wider. Adjusting the gap width of the outlet opening is likely to be of minor importance during continuous operation of the ring agglomerator. However, it does offer the possibility of adapting the gap width to different plastic recyclates to be processed, so that in different production facilities where different types or compositions of plastic recyclates are processed, the shredding can be easily adjusted to the optimal gap width of the outlet opening.

[0017] Secondly, however, particularly when starting up the plant after an interruption in operation, this axial adjustment option offers the advantage of initially setting the outlet opening of the ring agglomerator to a small size with a corresponding gap width, or even closing the outlet opening completely and only gradually increasing the gap width as the disc agglomerator's operating time increases. Such an adjustable shredding ring can therefore also be referred to as a start-up ring. When the ring agglomerator is started up, there is initially only a small amount of plastic recyclate between the two discs, and depending on the material used, it may happen that instead of the desired agglomerated material strands, incomplete, flake-like agglomerates are initially formed, which complicates further processing in plants downstream of the agglomerator.By reducing the size of the outlet opening or even closing it completely, the residence time of the material in the disc agglomerator can be extended until the desired material strands are formed.

[0018] The outlet opening can be enlarged based on in-house experience, for example, after a certain period of time. Alternatively, the outlet opening can be enlarged automatically, for example, by moving the shredding ring by motor, depending on the current consumption, for example, if the disc agglomerator is driven by an electric motor and the current consumption reaches a certain value due to the increased rotational resistance that occurs between the discs. This can be an absolute value, i.e., a specific current of X amperes.

[0019] However, the specific value can also be a relative value, resulting, for example, from the temporal progression of the power consumption. For example, the power consumption can rise with increasing fill level if increasing amounts of plastic recyclate enter the space between the two discs. If less material exits the outlet opening per unit of time than plastic recyclate flows into the space because the outlet opening is partially or completely closed, this leads to an increase in the amount of plastic recyclate in the space. Due to the higher fill level and the longer residence time, the material is processed more intensively in the disc agglomerator and takes on higher temperatures due to external influences and internal friction.

[0020] The resulting softening of the material leads to a reduction in the rotational resistance of the disc agglomerator, so that the power consumption of the drive motor at least does not increase further and typically even decreases again. If the power consumption is monitored by an electronic system control system, the outlet opening can be automatically enlarged based on the current consumption curve. This is achieved by automatically controlling the drive means of the comminution ring and automatically moving the comminution ring in the axial direction. The agglomerated material in the disc agglomerator can now leave the disc agglomerator through the outlet opening in the form of the desired material strands, which are then divided into the desired shorter pieces in the comminution ring.

[0021] The possibility of completely or partially closing the outlet opening of the disc agglomerator during the start-up phase can be achieved, depending on the design of the disc agglomerator and its outlet opening, by an axial adjustment of the two discs relative to each other, by an adjustable start-up ring - with or without crushing tools - or by a movable slide or similar closure elements closing the outlet opening.

[0022] In a conventional manner, the disc agglomerator can be designed in such a way that not both discs rotate, but rather one disc remains stationary. This disc, known as the stator, has the inlet opening through which the plastic recyclate enters the space between the two discs. The other disc, known as the rotor, is rotatably mounted and driven. With this design, the shredding ring can be held non-rotatably on the stator. Initial practical tests have shown that excellent shredding can be achieved even when the shredding ring is stationary, since the rotor entrains the agglomerated material strands and moves them not only radially but also tangentially relative to the stator and, accordingly, to the shredding ring, allowing the shredding tools to act on the material strands.

[0023] In principle, the shredding tools can simply form a counter-bearing against which the material strands emerging from the disc agglomerator collide, shearing them off and thus shredding them. In one embodiment, the shredding tools can be designed as knives, so that the shredding of the material strands can occur with as little resistance as possible and thus requires as little energy as possible.

[0024] The blades can advantageously be arranged at an angle of between 35° and 80° relative to the agglomerator axis, as far as the cutting edge of the blades is concerned. This achieves a pulling cut, which is advantageous in terms of energy consumption and also reduces the mechanical stress on the blades. With regard to these two aspects, the angle at which the cutting edges of the blades are aligned to the agglomerator axis can be between 45° and 60° in a configuration considered advantageous.

[0025] In one embodiment, the blades can be arranged in the ring shredder so that they can be replaced. This allows for quick and easy replacement of individual worn blades, or, if necessary, the replacement of one or all of the blades with differently shaped cutting edges.

[0026] In one embodiment, the knives can each be arranged in a knife holder that is replaceably mounted on the ring shredder. This also allows for the replacement of individual or all of the knives, as explained above. Furthermore, the knife holder can be designed as a stable element, eliminating the need to handle a narrow, delicate knife separately. For example, the knife holder, which can be made of a greater material thickness than the knife itself, allows the knife to be screwed to the ring shredder with a high tightening torque of the fastening screw without endangering the knife.

[0027] Regardless of whether the knives are attached directly to the ring shredder or via a knife holder, they can be mounted in a radially adjustable configuration. This allows the width of the annular gap between the outlet opening and the knives to be adjusted, thus influencing the size of the shorter pieces produced.

[0028] In one embodiment, the shredding ring can have multiple receptacles designed to accommodate shredding tools, for example, by holding the knives themselves or the knife holders equipped with the knives in the receptacles. In this embodiment, the shredding ring can have such a large number of receptacles that in many practical applications, a corresponding number of knives is not required. Accordingly, in this system embodiment, not all receptacles are equipped with a shredding tool. The number of shredding tools used can vary depending on the plastic recyclate used or the desired size of the shorter pieces into which the agglomerated material strands are to be shredded.

[0029] In this design, the receptacles that are not required and therefore not equipped with a shredding tool are covered with a cover element. This protects the receptacles themselves, for example, from contamination that could potentially complicate the subsequent installation of a shredding tool in this receptacle. Furthermore, personnel protection is achieved in terms of accident prevention by ensuring the system has the smoothest possible surface and avoiding a jagged outer surface of the shredding ring.

[0030] In one embodiment, the ring shredder may not only have a row of shredding tools arranged in a ring on the stator of the disc agglomerator, but rather have a row of shredding tools arranged in a ring on each of the two discs, so that the agglomerated material strands emerging radially outward from the outlet opening are shredded into short pieces by a shearing movement between the two different rows of shredding tools. The system accordingly has first shredding tools arranged on a first circular line with a first diameter and connected to a first disc of the disc agglomerator, and second shredding tools arranged on a second circular line with a second diameter and connected to a second disc of the disc agglomerator.The first and second comminution tools are movable relative to each other, as the two discs of the disc agglomerator are movable relative to each other. The diameters of the first and second circular lines are different, so that the first and second comminution tools interact like scissors, shredding the agglomerated material strands between them.

[0031] In this described embodiment of the system, it can be provided that the first and second comminution tools are each arranged on a retaining ring that is connected to the respective first and second disc of the disc agglomerator. Both retaining rings each have a free space designed as an annular groove, into which the comminution tools arranged on the other retaining ring can be inserted when the comminution tools are adjusted in the axial direction of the disc agglomerator. For example, if the comminution tools arranged on the stator are adjusted in the axial direction toward the rotor, the comminution tools each insert into the annular groove of the opposite retaining ring.Due to the possibility of being accommodated in the respective opposite retaining ring, the crushing tools can be designed so long that a shearing effect between the crushing tools can be ensured across the entire gap width, even with a large gap width of the outlet opening.

[0032] The invention is explained in more detail below using purely schematic representations, whereby individual design features of a specific embodiment of a plant for agglomerating and shredding plastic recyclate are not limited to this embodiment, but can also be implemented in other configurations and / or in other combinations.

[0033] Fig. 1 is a perspective view of a system for

[0034] Agglomeration and shredding of plastic recyclate, with a first disc agglomerator,

[0035] Fig. 2 and 3 Views of a first ring crusher, in a normal position

[0036] Fig. 4 and 5 views of the ring crusher of Fig. 2 and

[0037] 3, in a starting position,

[0038] Fig. 6 is a perspective view of a crushing ring of the ring crusher of Figs. 2 to 5,

[0039] Fig. 7 is a perspective view of a longitudinal section through a second ring crusher in the starting position,

[0040] Fig. 8 is a view of the ring crusher of Fig. 7 in the normal position,

[0041] Fig. 9 is a perspective view of a longitudinal section through a third ring crusher in the starting position,

[0042] Fig. 10 is a view of the ring crusher of Fig. 9 in the normal position,

[0043] Fig. 11 a vertical cross-section through a third disc agglomerator,

[0044] Fig. 12 is a vertical longitudinal section through the upper area of ​​the third embodiment in the starting position, Fig. 13 is a vertical longitudinal section through the lower area of ​​the third embodiment in the starting position, and

[0045] Fig. 14 shows a vertical cross-section similar to Fig. 11 through a fourth disc agglomerator.

[0046] Fig. 1 shows a plant 1 for agglomerating and shredding plastic recyclate, which has a disc agglomerator 2. Fig. 1 shows the viewer the back of a first disc, referred to as stator 3, of the disc agglomerator 2, with a central inlet opening 4 through which the plastic recyclate is introduced into a space between the two discs. Through the inlet opening 4, the view falls on a rotationally driven second disc, referred to as rotor 5, of the disc agglomerator 2. By means of three stator actuating cylinders 6s, the stator 3 can be moved in the axial direction so that the gap width between the stator 3 and the rotor 5 can be changed. By means of three ring actuating cylinders 6r, each of which has an essentially cylindrical protective cover, a shredding ring can be moved in the axial direction, as will be explained in more detail later.A housing 20 runs around the outer circumference of the stator 3 and the rotor 5.

[0047] In the lower circumferential area of ​​the two discs of the disc agglomerator 2, a conveyor device 7 is connected to the disc agglomerator 2, so that the agglomerates produced in the disc agglomerator 2 can be transported by means of the conveyor device 7 in a conveying direction F to a downstream device, in which the agglomerates are not merely temporarily stored but are further processed. An extraction connection 7a serves to remove gases produced during agglomeration from the agglomerate stream, so that unwanted gas entry, for example into a downstream extruder, can be reduced as much as possible. Figs. 2 and 3 each show the central components of a disc agglomerator 2, namely the rotor 5, which can be connected to a drive shaft, and the stator 3, which is largely concealed by a ring crusher 8.The ring shredder 8 consists of a shredding ring 9 and several shredding tools 10, with the shredding ring 9 itself being composed of three segments 11. In Figs. 2 and 3, the disc agglomerator 2 is in its normal position, which it normally assumes during operation, namely with a certain distance between the stator 3 and the rotor 5, so that a circumferential gap 12 is formed between the two discs on the outer circumference of the disc agglomerator 2. In this normal position, the gap 12 forms an open, annular outlet opening 34 between the two discs of the disc agglomerator 2 on its outer circumference.

[0048] The three ring actuating cylinders 6r allow the comminution ring 9, which is arranged radially outward on the lateral surface of the stator 3, to be moved in the axial direction and thus brought closer to or further away from the rotor 5, even if the stator 3 maintains its position. This allows the comminution ring 9 to be brought into the working position shown in Figs. 2 and 3, namely into a retracted position away from the rotor 5, in which the outlet opening 34 is open, so that the comminution tools 10 of the ring comminutor 8 are arranged radially outside the circumferential gap 12 and the outlet opening 34. The elongated agglomerates emerging from the outlet opening 34 between the stator 3 and the rotor 5 at the circumference of the gap 12 are captured by the comminution tools 10 and, assisted by the rotational movement of the rotor 5 and the inclined position of the comminution tools 10 shown in Figs. 2 and 3, are crushed in a pulling cut.When the ring actuating cylinders 6r are extended, the comminution ring 9 of the ring comminutor 8 is pushed over the gap 12 and in this way the outlet opening 34 is closed, which is referred to as the starting position of the disc agglomerator 2 and has the effect that the material located in the disc agglomerator 2 between the stator 3 and the rotor 5 cannot escape radially outwards from the outlet opening 34 as quickly when the disc agglomerator 2 is started up, but can be held in the disc agglomerator 2 for a longer time and can be mechanically processed.Although direct contact between the stationary and rotating components of the disc agglomerator 2 is avoided, the minimal opening width of the outlet opening 34 and the required directional deflection that the material must take on its path radially outwards create a type of labyrinth seal with the comminution ring 9 moved into the start-up position, which seals the outlet opening 34 sufficiently tightly from a practical point of view.

[0049] The start-up process is shortened by closing the outlet opening 34, and the escape of insufficiently agglomerated material can be largely or even completely prevented. Therefore, in deviation from the illustrated embodiment, the comminution ring 9 can also be used without comminution tools 10, so that in this case it can be referred to as a start-up ring, which merely has the closing function of closing the outlet opening 34 when the disc agglomerator 2 starts up.

[0050] Figures 4 and 5 show the central components of the disc agglomerator 2 of Figures 2 and 3, but in a so-called starting position, in which the two discs are spaced closer together, so that there is practically no gap 12 between the stator 3 and the rotor 5. In particular, it can be seen from Figure 4 that the rotor 5 is provided with a number of deflectors 14, which serve to convey plastic recyclate, which has reached behind the rotor 5 in the agglomerated or non-agglomerated state, radially outwards and to prevent it from reaching the drive shaft of the disc agglomerator 2.

[0051] Fig. 6 shows the ring shredder 8 separate from the other components of the disc agglomerator 2. The structure of the shredding ring 9, consisting of three segments 11, is visible. The shredding tools 10 each have a holder 15 and an interchangeable blade 16 arranged therein. The cutting edges of the blades 16 are each aligned at an angle of approximately 45° to the axis of the disc agglomerator 2, so that a pulling cut is achieved when, due to the rotational movement of the rotor 5, the agglomerates emerging from the gap 12 are guided in the direction of rotation against the blades 16. Because the agglomerates are carried along by the rotor 5 in the direction of rotation, the rotor 5 also provides the cutting energy required for cutting.

[0052] The holders 15 are fixed to the segments 11 by means of elongated holes in the radial direction so that the radial distance at which the knives 16 are located in front of the gap 12 can be adjusted. Each segment 11 has three so-called receptacles 17, namely mounting locations for comminution tools 10, and thus offers the possibility of mounting three comminution tools 10 on a segment 11. In the illustrated embodiment, only one comminution tool 10 is shown per segment 11, while the two remaining receptacles 17 are each protected against contamination and the ingress of plastic by means of a cover element 18 in order to enable problem-free mounting of a comminution tool 10 if necessary. Fig. 7 shows a section through the upper circumferential area of ​​the disc agglomerator 2. The stator 3 and the rotor 5 can be seen inside the housing 20.4 and 5, the embodiment of Fig. 7 is also in its starting position. In the embodiment of Fig. 7, the starting position is achieved by an axial adjustment of the stator 3 by means of the disc adjusting cylinders 6s, so that the gap 12 on the outer circumference of the two discs is closed by the stator 3 being adjusted axially up to the rotor 5. Accordingly, the two comminution rings 9 of the ring comminutor 8 also bear against one another. Both comminution rings 9 are each provided on their mutually facing end surfaces with a circumferential annular groove 22, which serves to accommodate the comminution tools 10 of the respective opposite comminution ring 9.A space between the discs 23 tapers down to a gap 12, and in the starting position shown, both the gap 12 and the outlet opening 34 on its outer circumference are practically closed, even if the stationary and rotating components of the disc agglomerator 2 do not touch each other, but rather have a minimal distance from each other.

[0053] Because the gap 12 is completely open as in Fig. 7 or, in contrast to the embodiment in Fig. 7, possibly slightly open, the plastic recyclate is held in the space between the discs when the disc agglomerator 2 is put into operation, i.e. when it is “started up”. Losses in the form of plastic recyclate that is not sufficiently agglomerated and is therefore not suitable for further processing can be reduced or even completely avoided in this way. Only when the material that has entered the space between the discs between the stator 3 and the rotor 5 during start-up has sufficiently agglomerated is the stator 3 removed from the rotor 5 by means of the adjusting cylinders 6r and the gap 12 opened wide enough for agglomerates to escape and enter the ring shredder 8.

[0054] Fig. 8 shows the embodiment of Fig. 7 after the disc agglomerator 2 has been started up, when it assumes its normal position and, by adjusting the stator 3, the space between the discs has been enlarged and the gap 12 and the outlet opening 34 have been opened. It can be seen how the comminution tools 10, arranged at different radii, interact in a shearing manner and have emerged from the annular groove 22 of the respective opposite comminution ring 9.

[0055] Fig. 9 shows a situation similar to Fig. 7, wherein in Fig. 9, a disc space 23 between the stator 3 and the rotor 5 is closed at the outer circumference by means of a disc actuating cylinder 6s, since the disc agglomerator 2 shown in Fig. 9 is in its starting position. In this embodiment, the comminution tools 10 are shown as cylindrical pins, which have a comminution-effective cutting or inclined surface outside their respective comminution ring 9.

[0056] Fig. 10 shows a situation similar to Fig. 8 for the embodiment of Fig. 9, in which the gap 12 is opened by corresponding adjustment of the stator 3 and the disc agglomerator 2 assumes its normal position.

[0057] Fig. 11 shows a view of a further embodiment of a disc agglomerator 2 and its rotor 5, with kneading strips 19 on the rotor 5. The housing 20 extends at a short distance around the two discs of the disc agglomerator 2. A ring shredder 8 is designed such that it interacts with the housing 20. The ring shredder 8 has a plurality of shredding tools 10, which are arranged on a shredding ring 9 and thus form a shredding ring. In contrast to the embodiment shown, the shredding tools 10 can be arranged on the circumference of the rotor 5 and fastened to it, so that they lie on a circular line and form a shredding ring, without this being designed as a physical ring.

[0058] In the embodiment of Fig. 11, the elongated agglomerates emerging from the gap 12 are first conveyed within the housing 20 by means of the comminution tools 10. Unlike the deflectors 14 of Fig. 4, the comminution tools 10 in Fig. 11 are not arranged on the rear side of the rotor 5, but rather adjoin radially to the outer circumference of the rotor 5. However, similar to the deflectors 14 in Fig. 4, they also serve to clear the space within the housing 20 into which plastic material enters and to transport the captured material.

[0059] By means of the comminution tools 10, the captured material is conveyed within the housing 20 to a housing opening 24, which forms the outlet opening 34 of the disc agglomerator 2. There, a shearing action to comminute the agglomerates occurs not with the aid of a second comminution ring, but rather in interaction with the edge of the housing 20 surrounding the housing opening 24. The elongated agglomerates are not crushed into separate, shorter pieces, but are literally shovelled into the space adjacent to the housing opening 24 and thus crushed. For this purpose, the comminution tools 10 have a front side acting on the material, which deviates from a purely radial orientation to the rear at a suitable angle.In this way, a spatula effect is achieved, with which the material is introduced into a conveyor line 21, which in the illustrated embodiment is directly connected to the housing 20. The conveyor line 21 of Fig. 11 has a conveyor screw 25 that transports the material in the conveying direction F. To ensure that the conveyor screw 25 is well filled, in this embodiment the conveying direction F runs opposite to the direction in which the rotor 5 moves in the region of the housing opening 24. The conveyor line 21 can, for example, be the intake screw of an extruder or a short transfer screw, which in turn is connected to an extruder screw.In both cases, the temperature losses of the material can be kept as low as possible, so that in an energetically particularly favorable design of the plant 1, the plastic material, which is initially agglomerated and then cut into shorter pieces, can be further processed in an extruder which is connected downstream of the disc agglomerator 2 by the shortest possible route.

[0060] The conveyor line 21 has an opening where it connects to the housing 20 of the disc agglomerator 2. Deviating from the illustrated embodiment, a closure element can be arranged between the housing 20 and the conveyor line 21, for example in the form of a slide valve arranged on the housing 20 or on the conveyor line 21. Similar to the possibility of closing the outlet opening 34 by means of an axially adjustable comminution ring 9 or an axially adjustable stator 3, the closure element can also be used to initially hold material in the disc agglomerator 2 during the start-up phase of the disc agglomerator 2 until the material is sufficiently agglomerated. Subsequently, the closure element, e.g., the aforementioned slide valve, is opened to allow the now sufficiently agglomerated material to flow out of the housing 20 and into the conveyor line 21.

[0061] Furthermore, not shown in the embodiment of Fig. 11, a suction connection can be arranged in the region of the transition from the housing 20 to the conveyor line 21 in order to be able to suck out gases produced during agglomeration before these gases can reach the conveyor screw 25.

[0062] A further development of the disc agglomerator 2 shown in Fig. 11 can consist in the omission of the scraper-like comminution tools 10. The housing 20 extends radially outwardly tightly around the discs of the disc agglomerator 2. The smallest possible distance between the housing 20 and the discs is, on the one hand, large enough to ensure friction-free and trouble-free operation of the disc agglomerator 2, but, on the other hand, small enough to prevent larger accumulations of agglomerates from radially moving outward between the discs. The pressure that builds up in the space 23 between the discs due to the material being conveyed into the disc agglomerator 2, as well as the centrifugal forces generated by the rotor 5 in the disc agglomerator 2 and the conveying effect of the kneading bars 19 cause the agglomerates to push radially outward.

[0063] Fig. 12 shows a section through the upper region of the disc agglomerator 2 of Fig. 11, which is in its starting position, so that the gap 12 and the outlet opening 34 on the outer circumference of the disc space 23 are closed. The section in Fig. 12 runs through a comminution tool 10 of the ring comminutor 8. By means of different screws 26, both the housing 20 is fastened to the stator 3 and the comminution tools 10 are fastened to the rotor 5. Behind the rotor 5, a rotor holder 27 is shown, which is provided with a sealing ring 28 on its outer circumference.

[0064] The sealing ring 28 has a thread profile 30, namely a helical groove, extending toward a space 29 that extends radially outside the gap 12 in a ring around the discs of the disc agglomerator 2, as well as on its radial outer side, toward the housing 20. The pitch of this thread profile 30 is coordinated with the direction of rotation of the rotor 5 in such a way that any material that has penetrated into the helical groove is conveyed back into the space 29.

[0065] Furthermore, sealing air is used to counteract the penetration of plastic into the area of ​​the thread profile 30: the housing 20 is provided with an air connection 31 to which a compressed air line can be connected. The compressed air flows into a circular sealing air channel 32 and from there into the area of ​​the thread profile 30, forcing any material located between the sealing ring 28 and the housing 20 back into the space 29.

[0066] Fig. 13 shows the lower circumferential area of ​​the disc agglomerator 2 of Figs. 11 and 12. The section runs in the longitudinal direction of the axis of rotation around which the rotor 5 rotates, and thus transversely to the conveyor screw 25. On the inside of the tubular housing of the conveyor line 21, the conveyor line 21 has several retaining grooves 33, each having a wedge cross-section. They serve to prevent the material, which has been introduced into the conveyor line 21 through the housing opening 24 with the aid of the comminution tools 10, from rotating together with the conveyor screw 25, so that a translatory movement of the material within the conveyor line 21 can be achieved as effectively as possible by means of the conveyor screw 25.

[0067] Fig. 14 shows, similar to the illustration in Fig. 12, the lower peripheral area of ​​another variant of a disc agglomerator 2. In this variant, no drivers are provided on the outer circumference of the rotor 5. The conveying effect with which the agglomerates are introduced into the conveying line 21 is based on the rotary movement of the rotor 5, the shape of the kneading bars 19 and the supply of material that is conveyed into the disc agglomerator 2. In order to keep the material between the stator 3 and the rotor 5 for a sufficiently long time when starting up the disc agglomerator 2 and to ensure sufficient agglomeration, the housing 20 can be closed by means of a housing slide 35 and / or the conveying line 21 can be closed by means of a screw slide 36. Purely as an example, Fig.14 shows both slides, so that, for example, depending on the plastic material being processed in the disc agglomerator 2, either the housing slide 35 or the screw slide 36 can be used. Deviating from Fig. 14, the disc agglomerator 2 can have only one of the two slides.

[0068] Reference symbol:

[0069] Plant disc agglomerator stator

[0070] Inlet opening rotor

[0071] 6s = Stator actuating cylinder 6r = Ring actuating cylinder Conveying device, 7a = Suction connection F = Conveying direction Ring shredder Shredding ring Shredding tool Segment Gap Deflector Holder Blade Receptacle Cover element Kneading bars Housing Conveying line Ring groove Disc space Housing opening Conveyor screw Screw Rotor receptacle Sealing ring Space

[0072] Thread profile Air connection Sealing air duct Retaining groove Outlet opening Housing slide Screw slide

Claims

Claims:

1. Plant (1) for agglomerating and crushing plastic recyclate, comprising an agglomerator, o designed to receive plastic waste and form it into elongated, cone-shaped or sausage-shaped agglomerates in a doughy state, o and designed as a disc agglomerator (2), with two discs, ■ which are profiled on their mutually facing surfaces, ■ are movable relative to each other, ■ are arranged parallel to each other and at a distance from each other ■ and create a disc space (23) between them, o and which has an inlet opening (4) for the plastic recyclate, which opens into the central area of ​​the disc space (23), o and which has an outlet opening (34) for the agglomerates, characterized in that a housing (20) extends annularly around the outside of the discs of the disc agglomerator (2) and has a housing opening (24) which connects to a conveying line (21), wherein a rotating disc of the disc agglomerator (2) is designed in such a way as to act on the agglomerates and to guide them under pressure into the conveying line (21) and that the conveying line (21) leads to a facility for further processing of the agglomerates.

2. System according to claim 1, characterized in that the outlet opening (34) is arranged in the outer circumference of the disc space (23), and a ring crusher (8) has crushing tools (10) which are arranged radially outside the outlet opening (34).

3. Plant according to claim 1, characterized in that comminution tools (10) extend radially within the housing opening (24) in a conveying capacity into a space (29) between the housing (20) and the disks of the disk agglomerator (2), such that they convey agglomerates located in this space to the housing opening (24).

4. Plant according to one of the preceding claims, characterized in that a rotating disk of the disk agglomerator (2) has conveying elements.

5. Plant according to claim 4, characterized in that the comminution tools (10) form the conveying elements.

6. Plant according to one of the preceding claims, characterized in that the conveying line (21) adjoining the disc agglomerator (2) has a conveying screw (25).

7. System according to claim 6, characterized in that the conveying line (21) is a screw extruder or a The transfer screw is designed to be connected to an extruder.

Images