pellet press

Abstract

Pelletizing device comprising a) a flat matrix plate (8) and b) a millstone with at least one millstone (31) which is rotatable with a vertical shaft (21) about a vertical axis (17) that is substantially perpendicular to the plane of the planar die plate (8), wherein the at least one millstone (31) is movable towards and away from the die plate (8), and c) one or more or all of a distance, displacement, or pressure measuring device for detecting and adjusting the distance of the at least one roller wheel (31) from the die plate (8) and / or the pressure of the at least one roller wheel (31) on the die plate (8), wherein a speed control of the edge mill is provided, and the main shaft (21) or a drive shaft (20) of the edge mill is electrically or hydraulically driven, The pelletizing device (1) comprises a receiving container (5), wherein the receiving container (5) extends around the edge mill and the main shaft (21), wherein the receiving container (5) is bounded by an outer circumferential wall (6), wherein the outer circumferential wall (6) has a diameter which is larger than the circular path (32) of the edge mill, wherein adjacent to the die plate (8) there is a circumferential conical wall section (37) which narrows the circumferential wall (6) funnel-like towards and bounding the circular path (32), so that material located in the receiving container (5) is guided onto the circular path (32), and wherein the king shaft of the (21) of the edge runner mill is polygonal in shape.

Description

[0001] The invention relates to a pelleting press, and in particular a flat die pelleting press, and a method for operating the same.

[0002] Die pellet presses are well-known. In particular, machines of this type are known in the market for their use in the agricultural sector for animal feed, in the tea and coffee sector, in the wood sector, especially for the production of wood pellets, as well as in the plastics and waste sectors.

[0003] When processing mixed materials, and especially mixed materials of plastomeric origin, one problem is that the different melting points and friction conditions of these materials require different processing methods, which cannot be readily provided.

[0004] Single-grade input products from production waste for return to the manufacturing cycle therefore require adjustments to the rollers and dies, as well as various press channel lengths and inlet cones.

[0005] The operation of pellet presses is specifically designed so that the product to be pelletized is optionally mixed with binders or other additives before being fed into the press. In the pellet press, the material is typically first mechanically processed and then pressed through a die. This mechanical processing is achieved, for example, by heavy rollers rolling over the material, compacting it. If the material can be melted, this compaction causes it to melt; otherwise, the material is forced through a die. Such a die consists of a plate or drum with a number of typically cylindrical bores. These cylindrical bores are usually conical on the material feed side, which compresses the material towards the narrower bore.

[0006] The mechanical processing is produced, for example, by a so-called edge roller mill, in which one or more rollers roll on a circular path over the die and press the material through the holes in the die, whereby the edge roller mill, for example, controls the pressure exerted by the rollers on the material, either through the weight of the rollers or through suitable pressure devices.

[0007] Typically, the material feed is controlled in such a way that the edge rollers do not roll directly on the die, but on a material bed of a certain thickness.

[0008] Mixed plastics and waste products are mostly used in thermal recycling and do not claim the homogeneity of the compact and are then introduced as so-called "fluff pellets" with stable bulk density into the blast furnaces of the steel industry or the rotary kilns of the cement industry as secondary fuel.

[0009] With single-type input products, such as production waste from plastics, there are significant differences in weight, friction and melting point depending on the type of plastic, which must be taken into account in order to obtain a flawless and homogeneous compact that can be returned to processing.

[0010] For example, polyamide dust or polyamide granules must be pressed with higher pressures and frictional resistances than polyethylene in the form of film dust or chips, given the same tool properties (die dimensions).

[0011] Fibers made of polypropylene and nylon (polyamide) also require different pressures or friction conditions to enable a homogeneous agglomeration process in the press holes or pelletizing holes of the die.

[0012] It is known that friction conditions can be adjusted by using different press hole lengths for different materials. However, this requires reconfiguring the pellet press when using different pipe materials.

[0013] EP 0 106 614 A2 describes a method and a device for determining the distance between the die and the rollers of a roller press.

[0014] CN 107 185 457 A discloses a roller press for forming biomass particles with an automatic gap regulation between roller and die.

[0015] From CN 203 971 878 U a flat die biomass granulation plant is known which includes a pelletizer, a regulator and a conveying device.

[0016] In US 2009 / 0 064 569 A1 and WO 91 / 02 644 A1, a pellet press with speed regulation of the rollers is shown.

[0017] US 2 752 007 A reveals a pelletizing press with a tapered housing section.

[0018] The KR 10-0978750 B1, the CN 202 387 436 U and the CN 201 385 445 Y each show a pelletizing press.

[0019] The object of the invention is to create a flat die pelletizing press which is able to reliably pelletize different materials in an improved manner and is particularly versatile with regard to the materials used.

[0020] The problem is solved with a flat die pelletizing press having the features of claim 1.

[0021] Another task is to create a method for operating a flat die pellet press that makes it possible to operate a die pellet press with high variability and reduced conversion effort depending on different materials, and to reliably pelletize different materials.

[0022] The problem is solved by a method having the features of claim 4.

[0023] Advantageous further training courses are indicated in the dependent sub-claims.

[0024] Furthermore, it is another task to create a control device for carrying out the procedure.

[0025] The task is accomplished with a control device having the features of claim 8.

[0026] Advantageous further training courses are indicated in the dependent sub-claims.

[0027] According to the invention, a flat die pelletizing press is created that largely automates the rotational speed of the roller mill, the pressure conditions, and the metered material distribution between the rollers. The invention provides for the variable and programmable distance between the rollers and the die, enabling pre-agglomeration of the plastic during plastic compression. Furthermore, the invention provides for pressure measurement between the roller and the die in such a way that the pressing process is controlled on the one hand, and a power-controlled material feed is enabled on the other.

[0028] According to the invention, the roller speed is also variable, such that automatic start-up for material that has cooled and re-cured in the die can be achieved by pre-running the roller via a timer and an adjustable material feed to heat the die and loosen the compact within it. This requires a program-controlled, time-reduced rotational speed of the roller, which ensures downward material pressure into the die's boreholes. As soon as the die reaches its predetermined, programmed operating temperature, thus ensuring the plastic within it has reached the appropriate temperature and the necessary lubricity in the boreholes, the rotational speed of the roller is increased.

[0029] According to the invention, it has been found that it is disadvantageous when the feed material builds up between the rollers, leading to wedging and ultimately blockage of the rollers. In the prior art, this results in smearing and ultimately blockage of the rollers. According to the invention, it has been found that the distribution paddles typically used in plastics applications, which are arranged between the rollers, are responsible for this. According to the invention, distribution paddles between the rollers are omitted, and an inclined material discharge from an inner outer wall of the pellet press is provided to ensure the material feed into the roller mill. This results in a forced material feed according to the invention.

[0030] According to the invention, it has also been found that it is advantageous to manufacture the drive shaft of the edge mill not as a round shaft, but as a polygonal, and in particular polygonal, for example triangular to dodecagonal. It has been found that in conventional systems, material can accumulate on the drive shaft, but it has been found that such material adhesion does not occur when the drive shaft has a polygonal cross-section. This also means, in particular, that the material not only does not adhere, but is conveyed under the edge mill roller pressure surfaces.

[0031] According to the invention, additionally, scrapers can be arranged on the main shaft, which scrape off the material accordingly, or scraper elements, such as scraper plates or scraper columns, can be present in front of the roller gears or between the running path of the roller gears and their outermost circumference of the main shaft, i.e. the outer edges, which scrape the material from the main shaft or from the outer edges of the main shaft and guide it in the direction of the path of the roller gears.

[0032] According to the invention, a profiling of the rollers is also provided, so that the roller grooves receive a special profiling through inclined and conical profile guidance.

[0033] According to the invention, it was also found that a fundamental requirement for automatic plastic pelletizing is temperature control of the die and, optionally, additional temperature control of the die support. In particular, the support and the die can be cooled.

[0034] According to the invention, this is ensured by a temperature control channel with defined inlet and outlet. The outlet can have a screwed-on channel cover or a permanently welded temperature control channel cover. Advantageously, the temperature control channel is designed for larger quantities of liquid with higher temperature control requirements; in particular, it can also be used for air, nitrogen, or other temperature control or cooling media. The use of appropriate heating media is also possible, especially to achieve faster plasticization when starting up a press containing still-hardened material.

[0035] According to the invention, the temperature control is automatically adjusted in such a way that the melting range of the plastic is adapted as closely as possible by the temperature control, thereby ensuring the homogeneity of the compact.

[0036] In this case, the temperature control can correspond to heating, especially at the beginning, and after a sufficient time, especially when the plastic is heated above a predetermined desired temperature, shift towards cooling, particularly due to the friction of the material in the channels.

[0037] In particular, the automated control of the press involves monitoring, controlling, and / or regulating one, several, or all of the following parameters: 1. Speed ​​or number of revolutions of the edge mill with a control range between 30 and 100 %; 2. Pressure from the edge mill on material and die, especially between 80 and 250 bar; 3. Power control of the metering screw for dosing the material; 4. Adjustment of the roller travel to the die. This involves a manual or automatic adjustment mechanism with a distance measuring device, whereby the pressure can be applied hydraulically or by other means, depending on the defined material. The aim here is to achieve a defined material input, for example, to create a direct pressing process into the die with a minimal distance between the roller and the die, or to achieve pre-melting of the material by means of a material slab through which the new material is forced. 5. Variable temperature control switchable between 30 and 180° matrix temperature for adaptation to the melting point of the plastic; 6. An automatic cutting or scraping device of the press, wherein the pellets are cut or scraped, wherein the cutting or scraping speed is set and infinitely variable and can be arranged in relation to the height to the die such that cutting occurs when in direct contact with the die and scraping occurs when arranged at a distance.

[0038] Pressure, temperature, and / or rotational speed are controlled variables that can be regulated individually or in combination. The control system takes into account one or more additional disturbances, such as the temperature of the device, the temperature of the material used, the melting point of the material, the shape of the material, the quantity of the material, and the rotational resistance of the [machine / rotational resistance].

[0039] The pressure of the edge mill on the material, the distance of the edge mill from a die plate, the pressure of the edge mill on a die plate, the pressure of the edge mill on the material, and the operating state of the pelletizing device are all relevant parameters. If these parameters are used as controlled variables, they should not be considered as disturbance variables.

[0040] The method according to the invention provides for the provision of specific routines for a desired number of predetermined materials and for these routines to be stored accordingly in a data processing system of the press.

[0041] The procedure further provides that, for safety reasons, in the event of a time overload or blockage of the press and to ensure a return to normal operation, the material supply is automatically interrupted, the edge roller mill is set to a minimum rotation speed, and / or the edge roller mill is locked in an upper end position, and / or the edge roller mill is lowered in stages from an upper end position in order to level out any material jamming under the rollers.

[0042] In particular, such an operating mode can provide, in the event of a blockage or overload, to interrupt the material feed, then to lift the edge roller conveyor to the upper end position and return it to the minimum rotational speed, then to lower it in stages or continuously to clear the material jams until the edge roller conveyor has reached its programmed end position again, and after reaching the end position, to allow the roller conveyor to continue rolling at the target speed and to restart the feeding process either immediately or after a sufficient waiting period.

[0043] According to the invention, it may additionally be provided to provide a water spray device in addition to or instead of the temperature control, which, for example, in the case of wood, chipboard dusts with adhesive components or paper dusts, chips or laminates, triggers a controllable friction process by adding water mist and thus achieves a material bond that makes the pellets suitable as additives for the production of composite materials.

[0044] According to the invention, the roller mill is preferably hydraulically driven, which enables synchronization of the pressure of the roller wheels on the material and / or the die, a corresponding speed adjustment of the rollers and the pellet discharge device, and the corresponding distance adjustment of the rollers to the die in one.

[0045] According to the invention, a measuring device can perform the distance adjustment manually to the end stop with a display of the distance or electronically variably via oil quantity measurement or electronic distance measurement.

[0046] Furthermore, performance control can be achieved by measuring the pressure applied by the rollers to the material and the die for the metering screw or device.

[0047] According to the invention, the press can also be designed to be mobile with skids for forklift transport. Advantageous for this purpose are electrical connections, particularly for mobile presses of 30 kW or stationary presses designed for a 37 kW connection with die diameters from 600 mm up to 60 kW for dies up to 800 mm.

[0048] Particularly in the case of stationary installation of the press according to the invention, the discharge direction of the pellets can be achieved by rotating an ejector ring or the die support forwards, laterally or backwards.

[0049] In stationary systems with hydraulic drive and separate control via a remote standing desk or in a stand-mounted design, it is also possible to provide the drive, the control and the actual pellet press as separate units.

[0050] In this embodiment, the control system and the hydraulics can be spatially separated as a drive / control unit for one or more pellet presses.

[0051] The control system and / or the hydraulic drive can be located outside the actual production area, e.g. in a separate control room.

[0052] In the case where the drive is spatially separated, separate hydraulic supply lines are provided to supply the pellet press(s) with drive energy.

[0053] Preferably, each hydraulic circuit is controlled separately.

[0054] Thus, for example, a number of pellet presses in other rooms could be driven and controlled / regulated from this room.

[0055] This can be advantageous in cases where one wants / needs to arrange an electrical system separately from the pellet press, for example in explosion protection designs.

[0056] In addition to the applications already described in the plastics sector, the pelleting press according to the invention can also be used in the areas of bio-waste, animal feed, waste processing for thermal recovery or for the separation processes of composite materials, e.g. rubber with textile and wires.

[0057] A mixture of materials and additives can be carried out via a corresponding number of silos, the silos preferably having a controllable discharge capacity, the silos being able to convey directly into the press, so that mixing can be carried out in the pellet press itself by the edge rollers without the need for external devices.

[0058] The invention thus relates in particular to a pelletizing device comprising a flat die plate and a roller mill with at least one roller which is rotatable with a vertical shaft about a vertical axis that is substantially perpendicular to the plane of the flat die plate, wherein the at least one roller wheel is movable towards and away from the die plate, and a distance, displacement, or pressure measuring device for detecting and adjusting the distance of the at least one roller wheel from the die plate and / or the pressure of the at least one roller wheel on the die plate.

[0059] One embodiment provides that at least one roller moves on a circular path around the vertical axis.

[0060] According to the invention, a speed control of the edge mill is provided, wherein the main shaft or a drive shaft of the edge mill is electrically or hydraulically driven.

[0061] According to the invention, the pelletizing device comprises a receiving container, wherein the receiving container extends around the edge mill and the main shaft, wherein the receiving container is bounded by an outer circumferential wall, wherein the outer circumferential wall has a diameter which is larger than the circular path of the edge mill, wherein adjacent to the die plate a circumferential conical wall section is present, which narrows the circumferential wall funnel-like to the circular path and bounds it, so that material located in the receiving container is guided onto the circular path.

[0062] According to the invention, the king shaft is designed to be angular. It is conceivable that the king shaft is polygonal, in particular 3 to 12 angular, wherein the outermost diameter of the king shaft corresponds to or is less than the inner diameter of the circular path, and wherein any gap that may exist between the circular path and the outermost diameter of the king shaft is bridged by strip-like wipers arranged on the king shaft and / or on the die plate.

[0063] Another aspect of the invention relates to a method for operating a pelletizing device, wherein, depending on a material used and / or the material condition, the material viscosity, the material temperature, the temperature of the die plate or depending on an operating state of the pelletizing device such as starting up, continuous operation, shutdown, material change, the rotational speed of a roller mill with at least one roller wheel and / or the distance or pressure or path of a roller mill is adjusted with respect to the die plate or with respect to a material to be pelletized.

[0064] One embodiment provides that the data of the operating states (start-up, continuous operation, shutdown, material type, material change, rotational speed, viscosity of the material depending on the processing time), the temperatures, the materials are stored in characteristic maps, whereby the pelleting device is controlled depending on a material or operating state of the pelleting device.

[0065] One embodiment provides that at least the matrix plate is temperature-controlled, wherein the matrix plate is electrically heated and / or is at least partially permeated with a temperature control fluid, wherein the temperature control fluid is controlled in such a way that the matrix plate is selectively cooled or heated or kept at a temperature.

[0066] One embodiment provides that the temperature control is carried out depending on an operating condition or a material used, a state of matter of the material, a shape of the material.

[0067] A further aspect of the invention relates to a control device for carrying out the method, wherein the control of the pelletizing device is designed to regulate the pressure, temperature and / or rotational speed of the edge mill as a function of at least one of the following parameters: temperature of the device, temperature of the material used, melting point of the material, shape of the material, quantity of the material, rotational resistance of the edge mill on the material, distance of the edge mill from a die plate, pressure of the edge mill on a die plate, pressure of the edge mill on the material, operating state of the pelletizing device, in order to set a desired viscosity and / or density for pelletizing the material.

[0068] Pressure, temperature, and / or rotational speed are controlled variables that can be regulated individually or in combination. The control system takes into account one or more additional disturbances, such as the temperature of the device, the temperature of the material used, the melting point of the material, the shape of the material, the quantity of the material, and the rotational resistance of the [machine / rotational resistance].

[0069] The pressure of the edge mill on the material, the distance of the edge mill from a die plate, the pressure of the edge mill on a die plate, the pressure of the edge mill on the material, and the operating state of the pelletizing device are all relevant parameters. If these parameters are used as controlled variables, they should not be considered as disturbance variables.

[0070] One embodiment provides that the control device is designed to receive measurement data, wherein the measurement data are data from measuring sensors that are at least one of the following: temperature of the device, temperature of the material used, melting point of the material, shape of the material, quantity of the material, rotational resistance of the edge roller on the material, distance of the edge roller from a die plate, pressure of the edge roller on a die plate, pressure of the edge roller on the material, operating state of the pelletizing device.

[0071] One embodiment provides that the control device is designed to control at least one of the rotational speed of the edge roller, temperature of the die plate, distance of the edge roller wheels of the edge roller from the die plate, and pressure of the edge roller on the die plate.

[0072] One embodiment provides an operating and display panel, showing a selection of materials and / or operating states and / or properties of a pelletized material (density, pellet length, pellet weight) for selecting a sequence of work steps in data processing.

[0073] The invention is explained by way of example with the aid of a drawing. The drawing shows: Fig. 1: a side view of the pellet press according to the invention; Fig. 2: a longitudinal section according to the section line AA to Fig. 1; Fig. 3: a top view of the edge runner mill; Fig. 4: a longitudinal section through another embodiment.

[0074] Fig. Figure 1 shows the basic structure of a possible embodiment of the pelletizing device 1. From top to bottom, the pelletizing device comprises a feed device 2 for receiving and processing the material to be pelletized, a discharge device 3 for collecting and discharging the pelletized material, and a drive device 4 for powering the pelletizing device. The receiving area 2 ( Fig. 1, Fig. 2) is, for example, a hollow cylindrical receiving container, wherein the hollow cylindrical receiving container 5 has a shell wall 6 and a filling opening 7 on its upper side. The hollow cylindrical receiving container 5 is connected to a die plate 8 on its underside or rests on the die plate 8. The die plate 8 is designed in a flat circular disk shape.

[0075] Below the die plate 8, the discharge device 3 is arranged, the discharge device 3 having an annular, circumferential wall 9 with which the discharge device 3 is closed off on the outside. The annular, circumferential wall 9 has a diameter that essentially corresponds to the diameter of the cylindrical wall 6 of the receiving container 5.

[0076] The surrounding wall 9 also has a discharge opening (not shown) on which a material chute 10 is provided for discharging the pelletized material.

[0077] Below the surrounding wall 9 are arranged a spacer ring 11 and a support plate 12. A scraper drive, which will be discussed in more detail later, is arranged inside the spacer ring 11. A drive unit 13 is arranged laterally on the support plate 12.

[0078] A drive housing 14, which is in particular multi-part and cylindrical but at least partially concentric, is attached to the support plate 12, wherein a drive unit 16 for the pelleting press is arranged at one end 15 of the pelletizing device 1 opposite the filling opening 7, wherein the drive unit 16 can be electrical or hydraulic.

[0079] Along a longitudinal axis 17 of the device 1, a drive pinion 18 extends into the housing 14 on the upper side of the drive unit 16, the drive pinion 18 being connected to a coupling unit 19, from which a drive shaft 20 axially passes through the drive housing, the circumferential wall 9, the die plate 8 and the receiving container 5.

[0080] In the area of ​​the receiving container 5, the drive shaft 20 is surrounded by a vertical shaft 21.

[0081] The die plate 8 has an annular recess 22, which is penetrated on one side by the drive shaft 20, wherein in the circular recess 22, which limits the discharge area or the discharge device 3 on the inside and is integrally connected to the support plate 12, a bearing sleeve 23 is provided, which preferably rotatably supports the drive shaft 20 via a plurality of bearings.

[0082] A hollow cylindrical discharge and conveying sleeve 24 is rotatably arranged on the outside of the bearing sleeve 23. This discharge and conveying sleeve 24 has a cylindrical base body 25 and, below the die plate 8 or within an annular recess 26 of the die plate 8, a discharge wheel 27 is located. This wheel may have corresponding struts or projections to ensure that pelletized material is discharged. A conveying plate 28 is located on the underside of the sleeve 24. This conveying plate rotates with the cylindrical sleeve 25 and may be inclined outwards to convey material accumulated in the discharge device outwards by centripetal forces. The discharge plate may be contoured on its upper surface or designed with ribs or webs to improve material conveyance.

[0083] The discharge and conveying sleeve 24 is driven by the drive unit 13, for which purpose a drive ring 29 may be provided below the discharge plate, which has teeth on the outside and is driven by a pinion 30 of the drive unit 13.

[0084] The main shaft is preferably rectangular, for example triangular or polygonal, and carries three roller wheels 31, which are rotatably mounted on the main shaft. The roller wheels 31 run on a circular track 32 on the die plate 8. In the area of ​​the circular track 32, the die plate has bores 33 through which material present within the feed device is pressed and thereby pelletized.

[0085] The running surface 34 of the roller wheels 31 can be contoured.

[0086] Preferably either the distance of the running surface 34 of the roller wheels 31 from the die plate 8 and / or the contact pressure of the roller wheels 31 on the die plate is adjustable and in particular infinitely adjustable and also variable during operation.

[0087] For this purpose, the king shaft 20 can be arranged axially movable on the drive shaft 20 such that, for example, a hydraulic distance adjustment or a mechanical distance adjustment (for example via screws) is provided.

[0088] In one embodiment according to the Fig. 1 and Fig. 2 the drive unit is located in the area of ​​the end 15.

[0089] In Fig.Figure 4 shows a measuring line 35 running from an outer wall 6 to an upper end 36 of the vertical shaft. This allows measurement data regarding the parameters pressure of the roller mill, speed of the roller mill, and distance of the roller mill to be measured and transmitted. However, this is only one possible embodiment; the measurement data can also be transmitted via lines at other locations. It is also possible, for example, to make the drive shaft hollow or to equip it with bores and to transmit the measured values ​​via slip rings at the lower end or telemetrically without contact.

[0090] In an advantageous embodiment, an inclined, circumferential and conical wall 37 is provided between the wall 6 on the one hand and the die plate 8, which serves to always bring material onto the circular path 32, so that no material is deposited next to the circular path and between the roller wheels 31 and the wall 6.

[0091] In addition to its angular design, the king shaft may also have ribs or webs or the like to bring material away from the king shaft onto the circular path 32, in order to prevent material from accumulating on the king shaft and to improve the pelletizing throughput.

[0092] According to the invention, the pelletizing device is controlled by means of an electronic control system, wherein a characteristic map control is stored for different plastics and / or plastic mixtures, so that an operator can easily control the operating mode of the pelletizing device depending on the material used. Here, for example, depending on the material to be pelletized and the thermal state of the material present in the feed device 2, it is provided, on the one hand, to control the rotational speed of the roller mill, consisting of the roller and the circular track 32 of the die plate, and in particular, for example, to start at a lower speed until the material is softened and only then to increase the speed.

[0093] Furthermore, it is planned to regulate the contact pressure of the roller wheels 31 on the die plate 8, also depending on the loading condition, the temperature and the material.

[0094] In particular, for example, with a still solid material, after the pelletizing device has been switched off and restarted with low pressure and a low rotational speed, the material can first be re-compacted and heated before the temperature is further increased with higher pressure and higher rotational speeds in order to pelletize the material through the bores 33 of the pelletizing device. However, this depends on the material, so it is also possible to select a high starting pressure and speed and then reduce one or both after reaching the desired operating state. This is because, especially with composite materials and resins, it can be observed that the frictional resistance increases with rising temperature.

[0095] In order to influence the temperature of the material during pelleting, the die plate 8 is provided to have cooling bores 38 or temperature control bores 38 outside the area of ​​the bores, i.e., both on the inside adjacent to the bearing sleeve 23 or outside adjacent to the cylindrical wall 6, through which a temperature control fluid can be passed through the die plate 8, for example to support the start-up process by heating the die plate to reach operating temperature more quickly and, once such temperature has been reached, to cool it if necessary to prevent the operating temperature from being exceeded.

[0096] The temperature control of the die plate 8 can of course also be stored in the corresponding characteristic curves.

[0097] Pressure, temperature, and / or rotational speed are controlled variables that can be regulated individually or in combination. The control system takes into account one or more additional disturbances, such as the temperature of the device, the temperature of the material used, the melting point of the material, the shape of the material, the quantity of the material, and the rotational resistance of the [machine / rotational resistance].

[0098] The pressure of the edge mill on the material, the distance of the edge mill from a die plate, the pressure of the edge mill on a die plate, the pressure of the edge mill on the material, and the operating state of the pelletizing device are all relevant parameters. If these parameters are used as controlled variables, they should not be considered as disturbance variables.

Claims

[1] Pelletizing device comprising a) a flat matrix plate (8) and b) a millstone with at least one millstone (31) which is rotatable with a vertical shaft (21) about a vertical axis (17) that is substantially perpendicular to the plane of the planar die plate (8), wherein the at least one millstone (31) is movable towards and away from the die plate (8), and c) one or more or all of a distance, displacement, or pressure measuring device for detecting and adjusting the distance of the at least one roller wheel (31) from the die plate (8) and / or the pressure of the at least one roller wheel (31) on the die plate (8), wherein a speed control of the edge mill is provided, and the main shaft (21) or a drive shaft (20) of the edge mill is electrically or hydraulically driven, The pelletizing device (1) comprises a receiving container (5), wherein the receiving container (5) extends around the edge mill and the main shaft (21), wherein the receiving container (5) is bounded by an outer circumferential wall (6), wherein the outer circumferential wall (6) has a diameter which is larger than the circular path (32) of the edge mill, wherein adjacent to the die plate (8) there is a circumferential conical wall section (37) which narrows the circumferential wall (6) funnel-like towards and bounding the circular path (32), so that material located in the receiving container (5) is guided onto the circular path (32), and wherein the king shaft of the (21) of the edge runner mill is polygonal in shape. [2] Pelletizing device according to claim 1, characterized by , that at least one roller wheel (31) moves on the circular path (32) around the vertical axis (17). [3] Pelletizing device according to one of the preceding claims, characterized by , that the king shaft (21) is 3 to 12 square, wherein the outermost diameter of the king shaft (21) corresponds to or is less than the inner diameter of the circular path (32), wherein any gap that may exist between the circular path (32) and the outermost diameter of the king shaft (21) is bridged by strip-like wipers on the king shaft (21) and / or on the die plate (8). [4] Method for operating a pelletizing device, wherein, depending on a material used and / or the material condition, material viscosity, material temperature, temperature of the die plate (8) or depending on an operating state of the pelletizing device (1) such as starting up, continuous operation, shutdown, or material change, the rotational speed of a roller mill with at least one roller wheel (31), and / or the distance, the travel, or the pressure of a roller mill relative to the die plate (8) or relative to a material to be pelletized is adjusted, wherein, for safety reasons, in the event of a temporal overload or a blockage of the pelletizing device (1) and to ensure a return to normal operation, the material feed is automatically interrupted, and the roller mill is set to a minimum rotational speed, and / or the roller mill is locked in an upper end position,and / or the edge runner is lowered in stages from the upper end position to level out any material jamming under the rollers. [5] Method according to claim 4, characterized by , that the data of the operating states (start-up, continuous operation, shutdown, material type, material change, rotational speed, viscosity of the material depending on the processing time), the temperatures, the materials are stored in characteristic maps, whereby the pelleting device (1) is controlled depending on a material or operating state of the pelleting device (1). [6] Method according to claim 4 or 5, characterized by , that at least the matrix plate (8) is tempered, wherein the matrix plate (8) is electrically heated and / or is at least partially permeated with a tempering fluid, wherein the tempering fluid is tempered in such a way that the matrix plate (8) is selectively cooled or heated or kept at a temperature. [7] Method according to any one of claims 4 to 6, characterized by , that the temperature control is carried out depending on an operating condition or a material used, a state of matter of the material, a shape of the material. [8] Control device for carrying out the method according to any one of claims 4 to 7, characterized by, that the control of the pelletizing device is designed to regulate the pressure, temperature and / or rotational speed of the edge mill as a function of at least one of the following: temperature of the device, temperature of the material used, melting point of the material, shape of the material, quantity of the material, rotational resistance of the edge mill on the material, distance of the edge mill from a die plate, pressure of the edge mill on a die plate (8), pressure of the edge mill on the material, operating state of the pelletizing device (1), in order to set a desired viscosity and / or density for pelletizing the material. [9] Control device according to claim 8, characterized by, that the control device is designed to receive measurement data, wherein the measurement data are data from measuring sensors that include at least one parameter from temperature of the device, temperature of the material used, melting point of the material, shape of the material, quantity of the material, rotational resistance of the edge roller on the material, distance of the edge roller from a die plate (8), pressure of the edge roller on a die plate (8), pressure of the edge roller on the material, operating state of the pelletizing device (1). [10] Control device according to claim 8 or 9 comprising a control panel displaying a selection of materials and / or operating states and / or properties of a pelletized material (density, length of pellets, weight of pellets) for selecting a sequence of work steps in data processing.

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