Granulation process

Abstract

A granulation process is proposed for producing granules (11) consisting of a multitude of granule particles (12). During the granulation process, a granulation process involving particle growth is carried out in a process chamber (4) of a process vessel (3) bounded by a vessel wall (5) and monitored using an electrically controlled image acquisition unit (42). During this monitoring, two-dimensional images of the granules (11) are taken with the image acquisition unit (42). These images are then evaluated by an electronic control unit (36) and, after evaluation, used to specify variable operating parameters that influence the operating state of the granulation process.It is essential that the images are taken as inline images during the ongoing granulation process of the granules (11) in the process chamber (4) undergoing particle growth.

Description

[0001] The invention relates to a granulation process for producing a granulate consisting of a plurality of granulate particles, wherein a granulation process accompanied by particle growth is carried out in a process chamber of a process container delimited by a container wall, which granulation process is monitored using an electrically controllable image recording unit with which two-dimensional images of the granulate are taken, which are then evaluated by means of an electronic control device and, after their evaluation, are used to specify variable operating parameters influencing the operating state of the granulation process.

[0002] A granulation process of the aforementioned type is known from DE 100 61 085 A1 and is carried out there using a granulation device having a granulation section containing a granulation drum, followed by a drop shaft with a funnel, which is continuously supplied on the inlet side in a vertical direction with granulate particles generated in the granulation section. The granulate particles obtained in this way can be removed from a sampling opening of the drop shaft and fed to a field unit equipped with a color camera. The granulate particles fall downwards in an object plane of the color camera, and an image sequence of the falling granulate particles is recorded during the fall. While the image sequence is recorded, the color camera determines the grain size and the grain size distribution based on the projected particle area.In a downstream processing unit, the recorded image sequences are analyzed and digitally processed so that they can be displayed on an output device, e.g., a monitor. The processing unit also determines process-specific parameters, which serve as input variables for a system controller equipped with fuzzy logic modules. After a comparison with target values, output signals are generated to influence the operating parameters of the granulation process in order to achieve the desired product quality. In addition to being recorded in a field unit, the image sequences can also be recorded directly on the granulate particles falling from the granulation section into the drop shaft. This well-known granulation process can be used to produce, for example, fertilizers and pharmaceutical products.

[0003] WO 2019 / 091507 A1 describes a method for producing granular solid particles. The produced particles are detected using an optical detection system, and at least one characteristic of the produced particles is determined from the optically detected data of the produced particles. Based on the determined characteristic, at least one parameter of the production process for further particles is then automatically influenced. The optical detection of the particles occurs after they leave a process container in which a granulation process has taken place and which is equipped, for example, with a granulation disc, the rotational movement of which causes agglomeration of an added starting substance.With the help of an electronic control device, for example implemented by a computer, control data are generated which are used to optimize subsequent granulation processes, for example to control a valve arrangement with which the supply of starting substances for the granulation process can be influenced.

[0004] Independently of the aforementioned prior art, the applicant has internal knowledge of pelletizing plants in which pellet-shaped granules are produced using a pelletizing process. An operator takes samples from the production system at certain intervals during the granulation process using a sampler and examines the results outside the process system using a microscope or camera. A small number of the sampled particles are measured manually and, if necessary, analyzed using system software. The further process control depends on this assessment. Since the growth process of the resulting granulate particles is very rapid, the samples often cannot be taken and analyzed at a sufficient speed, which can lead to uncontrolled particle growth and the desired product properties not being achieved.A further limitation of this in-process testing method is the dependence on experienced operators and the relatively small number of particles that can be analyzed per sample taken.

[0005] The invention is based on the object of taking measures that allow a rapid analysis of the granulation process during the process so that granules of high product quality can be produced reliably and reproducibly.

[0006] This task is solved with a granulation process in which, in conjunction with the procedure mentioned above, the images are taken as inline images of the granulate in the process chamber during particle growth during the granulation process.

[0007] According to the invention, the granulation process, which particularly takes place in a granulation device, is monitored inline, i.e. directly in the process chamber during ongoing granulation, with the granulate particles undergoing growth being observed. During the granulation process, images are taken as inline images of the granulate particles undergoing growth in the process chamber during the granulation process. In this way, it is possible to react very quickly to the current process sequence and, for example, to very rapid particle growth. Since the evaluation can be carried out by examining a large quantity of particles, unlike sampling that only takes place from time to time, the achievable analysis result is significantly more precise and representative. Accordingly, very good and stable product qualities can be achieved combined with low waste.The analysis is based on optical data provided by an image acquisition unit positioned in the granulation process area in such a way that, during an ongoing granulation process, two-dimensional (2D) images of the interior of the process chamber and thus of the granules currently undergoing granulation are possible. During these inline image acquisitions, the granulation process proceeds uninterrupted. The image acquisition unit can be placed, for example, inside the process chamber or outside the process chamber, with the option of taking internal images of the process chamber through the structure of the process container.During the process, the granulate particles currently undergoing a granulation process in the process chamber can be photographed directly. After subsequent evaluation of the images, the further granulation process can be influenced by modifying variable operating parameters of the current granulation process based on the images. Due to the possibility of real-time image recordings, the process sequence according to the invention proves to be particularly advantageous for monitoring and controlling granulation processes with very rapid particle growth, since the optical inline evaluation enables process control with very short response times.With the help of inline image recordings, which are particularly used to create image sequences consisting of several images taken in immediate succession, the granulation process can be monitored in a variety of ways based on optically detectable product parameters, for example, particle size, grain size distribution, roundness, or other morphological properties. The granulation process is preferably carried out in such a way that images of the granulate particles are taken in regular, in particular freely selectable, and preferably adaptable to the production speed, image sequences. The type of variable operating parameters responsible for the operating state of the granulation process and which can be influenced include, for example, temperature, volume flow rates, and / or operating time.

[0008] Notwithstanding the plural used above and below with regard to operating parameters, the variable operating parameters may also comprise only a single variable operating parameter in a simple process sequence. Reference to variable operating parameters should be understood as a reference to one or more variable operating parameters.

[0009] Advantageous further developments of the invention emerge from the subclaims.

[0010] Preferably, the inline images of the granules in the process chamber are taken by the image acquisition unit from outside the process chamber through a transparent wall section of the process vessel. This allows the process chamber to be used for the granulation process without any disruptions due to process monitoring, and the image acquisition unit does not come into contact with the granules in production.

[0011] It is advantageous if the electronic control device performs image processing of the images captured by the image acquisition unit, during which granule-related result values, such as, in particular, an average particle diameter and / or a size distribution of the granule particles and / or a mean particle diameter, are calculated. Based on the calculated granule-specific result values, adjustment signals are generated that specify variable operating parameters that influence the operating state of the granulation process.

[0012] Preferably, the adjustment signals are generated by means of a closed-loop control system based on a comparison between, on the one hand, the granule-related result values ​​and, on the other hand, specified target values. This is conveniently done in a closed-loop control system.

[0013] The granulation process advantageously performs image processing such that, for the calculation of the granule-related result values, only those granule particles visible in the acquired images are identified as reference granule particles that lie within a focal plane of the image acquisition unit. Only these identified reference granule particles are used as the basis for calculating the granule-related result values. During the calculation, the identified reference granule particles are preferably electronically measured with regard to their particle size, in particular their circumference.

[0014] The granulation process is expediently carried out by means of a granulation device which has a granulation apparatus which has the process container which delimits the process space, wherein the image recording unit for carrying out the process is arranged in the region of the granulation apparatus in such a way that it can produce the images of the process space during a granulation process and thus the inline images of the granulate undergoing a granulation process in the process space.

[0015] The granulation apparatus used to carry out the process can, in principle, be based on any functional principle. A fluidization granulation apparatus is considered advantageous, as it fluidizes the granules during the granulation process by means of a process gas flowing through it. A fluidized-bed granulator is particularly suitable in this context, particularly for spray granulation, spray agglomeration, spray coating, or spray encapsulation. The process gas contributes to the granules being swirled inside the process vessel, forming a so-called fluidized bed. For special requirements, spouted bed technology can be used.

[0016] The use of a fluidized bed generator designed as a rotor fluidized bed granulator is considered particularly advantageous for the process. This generator is equipped with a motor-driven rotor, preferably with a rotor plate. This type of granulation device can produce granules with particularly high-quality roundness and surface finish. The rotating rotor plate transports the granules outward into the process gas stream, which then entrains them, forming a particularly toroidal fluidized bed.

[0017] The aforementioned rotor fluidized bed generator is one possible embodiment of a granulation apparatus generally referred to as a rotor granulator and usable for carrying out the granulation process. In another embodiment of a rotor granulator, which is also advantageous within the scope of the invention, process gas, in particular air, passed through the process vessel past the rotor is used primarily or exclusively as a barrier gas, while the actual granulation is caused by the granulate particles being moved through the process chamber by the rotating rotor in conjunction with blade-like structures arranged on the rotor and / or process vessel, in particularly toroidal granulate streams with continuous mixing. As the granulate rolls along the surfaces of the process vessel and the rotor, including the blade-like structures, granulate particles with a high degree of roundness are formed.

[0018] The granulation apparatus used for the process can, for example, be designed for so-called high-shear granulation. High-shear granulation is a granulation shaping process in which a binder liquid is added to powdered particles in a closed process vessel containing mixing tools and a chopper. The mixing tools conveniently include a motor-driven rotor, so the granulation apparatus can also be referred to as a rotor granulator. Dense granules are formed via the resulting liquid and solid bridges.

[0019] If the granulation apparatus used has a motor-driven rotor, a variable operating parameter of the granulation process can be the speed of the rotor, which can be specified by appropriately controlling an associated electric drive motor.

[0020] In a preferred embodiment of the granulation method, the residence time of the granulate particles in an ongoing granulation process, which is also referred to below as the processing time, is provided as a variable operating parameter. In a granulation device designed for batch operation, the processing time can be specified, for example, by switching the granulation process on and off. In continuous granulation processes, the processing time results in particular from the time difference between the filling of the starting substances and the removal of the granulate particles into or from an ongoing granulation process. When carrying out the method, the processing time can be specified, for example, by an electronic control device provided for evaluating the two-dimensional images recorded by the image recording unit.

[0021] The process chamber of the process vessel used is expediently connected to a process gas inlet for feeding in a suitably tempered process gas and further to a process gas outlet for discharging the process gas. The process gas can be, for example, heated air or a heated inert gas. The process gas dries the substances in the process chamber, thereby causing, for example, granulation by spray granulation or spray agglomeration. Additionally or alternatively, the process gas can be used, particularly in a rotor granulator, as a barrier gas to prevent granule particles from falling downwards between the rotating rotor and the wall of the process vessel.It is advantageous if the volume flow and / or the temperature of the process gas is used as a variable operating parameter that can be changed by the electronic control device in order to influence the operating state of the granulation process, in particular depending on the evaluation of the recorded images.

[0022] To perform spray granulation, the granulation apparatus used is advantageously equipped with a spray nozzle arrangement that allows a granulation liquid to be sprayed into the process chamber of the process vessel. During the granulation process, this makes it possible to spray solid-containing liquids such as solutions, suspensions, or melts into the process chamber. There, the liquid components evaporate due to a high heat exchange with a process gas, and the remaining solids form small particles as carrier cores. These particles are wetted with another liquid, so that after further evaporation, a solid shell is formed around the carrier core. Since this process is continuously repeated, a continuous growth of the granulate particles occurs layer by layer.In an alternative spray agglomeration process, very small, powder-formed particles are moved in a fluidized bed induced by a process gas and sprayed with a binder liquid from the spray nozzle arrangement. The particles bond to form agglomerated granules due to the formation of liquid bridges. The spraying process continues until the desired size of the agglomerated granules is reached.

[0023] When a spray nozzle arrangement is present, the variable operating parameters of the granulation process include, in particular, the volume flow and / or the spraying time and / or the droplet size of the granulation liquid fed into the process chamber.

[0024] To carry out the process, a granulation apparatus equipped with a feed device is preferably used, allowing the carrier cores underlying the granulate structure, particularly in powder form, to be introduced into the process chamber. In this process, the subsequently sprayed granulation liquid serves only as a transport component for introducing the solid to be applied layer by layer. In this case, a variable operating parameter of the granulation process can be the quantity of carrier cores that can be fed into the process chamber.

[0025] Depending on the design of the granulation device, the images of the granulate can be captured by the image capture unit using an image capture unit located directly within the process chamber or by an image capture unit located outside the process chamber. For safety reasons, particularly explosion protection, an image capture unit located outside the process chamber is generally preferred. In this case, the wall of the process container expediently has at least one transparent wall section, in the area of ​​which the image capture unit is located outside the process chamber. The images of the process chamber, and thus the inline images of the granulate contained therein, are captured from outside the process chamber through the transparent wall section.

[0026] The transparent wall section is, in particular, a limited area of ​​the container wall that is enclosed by an opaque wall section of the container wall, so that the transparent wall section defines a transparent viewing window. This viewing window is preferably made of transparent glass or plastic.

[0027] Alternatively, it is possible, for example, to use a process container constructed in such a way that the container wall consists at least predominantly and preferably entirely of a transparent material, for example of a correspondingly high-quality transparent plastic, wherein the transparent wall section used for the image recordings is a partial area of ​​the large-area transparent container wall.

[0028] An image recording unit located outside the process chamber and thus externally can be attached to a separate support structure independent of the process container for carrying out the process, but is preferably fastened directly to the outside of the process container. It is expedient if the process container has, for this purpose, a fastening interface referred to as a container fastening interface on the outside of the container wall. This fastening interface is coordinated with the structure of the image recording unit and to which the image recording unit is fastened in a use position for carrying out the process. The container fastening interface is preferably designed for screw fastening of the image recording unit, so that the image recording unit can be easily and quickly removed from the process container for maintenance purposes or other occasions.

[0029] For particularly detachable mounting on the process vessel, the image acquisition unit is expediently equipped with a mounting interface, referred to as the image acquisition unit mounting interface for easier differentiation. The image acquisition unit mounting interface is functionally coordinated with the aforementioned optional vessel mounting interface.

[0030] The image recording unit is expediently equipped with an electromechanical connection device, via which an electrical connection is established with an electronic control device that specifies one or more variable operating parameters of the granulation process during the process. The electromechanical connection device expediently contains a plug-in connection device for at least one electrical cable or even directly at least one outgoing electrical cable itself.

[0031] In particular, an internet connection to the electronic control device is established via the electromechanical connecting device, which enables data exchange between the two components, and the power supply for providing the required operating voltage is also expediently carried out via this electromechanical connecting device.

[0032] The image acquisition unit used for the granulation process is preferably equipped with an optoelectrical assembly comprising an image sensor and a lens positioned upstream of the image sensor for capturing the image to be captured. The image sensor is expediently part of a sensor unit integrated into the optoelectrical assembly, which, in addition to the image sensor, also comprises other electronic and / or mechanical components. Together, the sensor unit and the lens form a camera, which is in particular a color camera but can also be designed as a black-and-white camera.

[0033] The lens is preferably a telecentric lens, which expediently has a fixed focal length. This offers the advantage that the particle size is clearly defined in the focused image area and, unlike with wide-angle lenses, the difference between small, close-up particles and large, distant particles is clearly visible. Compared to a telecentric lens with a variable focal length, which can also be used in principle but in which the focal plane must be adjusted by adjusting the lens, a telecentric lens with a fixed focal length allows for significantly simpler adjustment and evaluation, eliminating the need for complex conversions and calibration measures. A recorded pixel always corresponds exactly to a unit of length that depends on the design of the lens, so that no particularly complex conversions are required for image evaluation. The telecentric lens is, in particular, of a bi-telecentric design.

[0034] The telecentric lens, which preferably has a fixed focal length, results in a relatively shallow depth of field. It is, for example, in the range of only 1.1 mm. Accordingly, the process requires precise positioning of the focal plane defined by the optical components, which defines an image acquisition plane with optimal image sharpness. To ensure the greatest possible flexibility for adjustment measures, it is advantageous for the image acquisition unit to have an electrically actuated linear module supporting the optoelectrical assembly. The linear module enables continuous linear movement of the optoelectrical assembly to change and adjust the position of the focal plane, also referred to as the focal plane.There is a fixed distance between the lens and the image sensor, which remains constant even when the position of the optoelectrical assembly changes. Thus, even if the focal plane changes, no calibration is required. It is simply a matter of positioning the optoelectrical assembly so that the granule particles to be captured are within the working area or focal plane of the lens.

[0035] Instead of an electrically actuated linear module, the image recording unit for positioning the optoelectric assembly may alternatively contain a different type of positioning device, for example a manually operated device with clamping screws for releasably fixing any desired position.

[0036] To record clear images, it is advantageous to use an image recording unit equipped with an illumination device that illuminates the area to be imaged, usually at least the focal plane of the optoelectrical assembly. The illumination device is preferably implemented using LED technology. When carrying out the method, the illumination device can be used either in pulsed operation adapted to the frequency of the image recordings or in continuous operation. The latter is technically easier to implement, since the exposure time of the recorded image does not have to be adjusted to the bright phase of a flash light. Advantages can also be expected in terms of explosion protection due to the avoidance of ignition sparks with continuous light.

[0037] The illumination device preferably includes a ring light arranged coaxially with an optical axis of the optoelectric assembly. This allows the granulate particles moving past the focal plane to be photographed without disturbing shadows, thus allowing for precise measurement. The illumination of the focal plane is very homogeneous.

[0038] The granulation process is particularly designed such that the two-dimensional inline images of the granulate taken during a granulation process in the process chamber are evaluated by means of the electronic control device mentioned above. Subsequently, the variable operating parameters of the granulation process are specified depending on the evaluation results in order to influence the operating state and thus the process conditions as desired. In particular, using an electromechanical connection device mentioned above, the image data of the captured images can be transmitted from the electrically operated image acquisition unit to the electronic control device.

[0039] Preferably, bidirectional signal transmission is possible between the image acquisition unit and the electronic control device. This signal transmission is used not only for image analysis but also for electrically controlling the image acquisition unit, including the transmission of electronic image acquisition commands to trigger the desired image recordings. This is conveniently done via a wired connection via a corresponding electrical communication line, but can also be done wirelessly, particularly via radio transmission.

[0040] The electronic control device expediently contains an electronic data processing device with which the images captured by the image recording unit are processed during the granulation process. In particular, the electronic data processing device calculates granule-related result values ​​based on the obtained image data. For the sake of simplicity, these are also referred to simply as result values ​​and which are in particular one or more parameters from the group of the average particle diameter of the granulate particles, the size distribution of the granulate particles, and the mean value of the particle diameters. Taking image sequences into account, a growth curve of the particle growth can be generated from the size distribution, from which the temporal course of the particle growth can be read.Overall, the granule-related result values ​​reflect the current actual state of the granule particle quality in the ongoing granulation process.

[0041] The electronic data processing device expediently performs image processing such that the calculation of granule-related result values ​​is based, at least essentially, only on the granule particles located in the focal plane of the image processing unit. Particularly when using a telecentric lens, this ensures that the granule particles considered are based on the same reading scale or measurement scale and, accordingly, the calculated result values ​​do not contain any relevant distortions. For better differentiation, the granule particles located in the focal plane are referred to as reference granule particles, whereby only the granule particles identified as reference granule particles are considered when calculating the granule-related result values.The particle size is preferably taken into account, whereby the particle size, in particular the particle diameter, can be determined based on an electronically measured particle circumference.

[0042] The electronic control device used for the granulation process is expediently equipped with an electronic operating state setting device that communicates with the electronic data processing device and, based on the previously determined granule-related result values, sets the variable operating parameters that influence the operating state of the granulation process. For this purpose, the operating state setting device can output signals, referred to as operating signals, corresponding to the desired operating parameters, to the device components of the granulation device responsible for the respective operating parameters.The operating signals are output - depending on the equipment - for example to a liquid pump spraying the granulation liquid, to a conveyor unit of a feed device for carrier cores, to a drive motor of a rotor fluidized bed granulator and / or to a blower supplying the process gas and are transmitted by the operating state setting device to one or more of these device components when carrying out the method according to the invention.

[0043] The electronic operating state setting device can be a separate component of the electronic control device or an integral component of the electronic data processing device.

[0044] The electronic control device used is expediently designed so that it can execute the aforementioned control for generating the adjustment signals, particularly in a closed control loop. For this purpose, the electronic control device is expediently equipped with a control device in which a comparison takes place between the granulate-related result values ​​calculated on the basis of two-dimensional image recordings and previously stored setpoints, with the adjustment signals for the electronic operating state adjustment device being generated as the comparison result. Expediently, the granulate-related result values ​​function as a controlled variable in the control device, which is compared with the previously stored setpoints stored as a reference variable.The operating state setting device is able to interpret the received setting signals and, based on this, output the operating signals as manipulated variables to the device components.

[0045] The electronic control device is expediently equipped with an input device, with which, in particular, the setpoint values ​​are entered into the electronic data processing device for internal storage. The input device includes, for example, a keyboard and / or an interface for an electronic input device.

[0046] It is further advantageous if the electronic control device used has an electronic output device, through which, in particular, the granulate-related result values ​​calculated by the electronic data processing device are output. The output device can also be designed and used to output further process-related information, for example, to output current operating conditions, such as information regarding the temperature of a process gas or the flow rate of a sprayed granulation liquid. Particularly effective monitoring is possible if the output device includes a display device for visualizing the information to be output.Such a display device can, for example, be formed by a monitor capable of displaying electronically provided information alphanumerically and / or as curves and / or in the form of diagrams. For example, the average size, average size distribution, and / or morphology of the photographed granule particles can be displayed and / or selected for display in continuous curves over the process time in freely definable subdivisions.

[0047] For particularly convenient and precise operation of the granulation device, the electronic control unit used is expediently equipped with artificial intelligence (AI), hereinafter referred to simply as "AI." For particularly effective image processing, an AI with a convolutional neural network is preferably used. The AI ​​is capable of interpreting the 2D images captured by the image acquisition unit and identifying the aforementioned reference granule particles for use in calculating the granule-related result values. By training the AI, particle identification with high accuracy can be achieved.The training is carried out manually by providing the artificial intelligence with images in which the reference granulate particles are previously marked manually, in particular using the input device mentioned above.

[0048] Artificial intelligence (AI) is expediently equipped with, among other things, data processing components, learning algorithms, decision components, output components, and interaction components. The data processing components are also responsible, among other things, for processing data required for training the AI, which, for example, is manually defined as reference granule particles in the manner mentioned above. The learning algorithms are responsible for training the AI ​​and include, for example, machine learning algorithms such as decision trees or artificial neural networks, in particular at least one convolutional neural network. The decision components serve the AI's decision-making process and essentially carry out a control process, analyzing the available data—in particular, the granule-related result values ​​and the desired target values—and making targeted decisions.The decision components include, for example, decision rules or heuristic approaches. The output components serve to output results or other information, as already mentioned, for example, by generating graphics, diagrams, tables, or even just text. They can be used, for example, to control the output device. The interaction components are components through which the AI ​​interacts with its environment and are implemented, for example, as electrical interfaces through which the setting signals for the operating state setting device are output.

[0049] The invention is explained in more detail below with reference to the accompanying drawings, which show: Fig. 1 shows a preferred embodiment of a granulation device which can be used or is used to carry out the granulation process according to the invention, in a schematic representation in the state of a granulation process running while carrying out a preferred granulation process according to the invention, wherein granules located in a process container are illustrated in a detail enlarged by a dot-dash frame, Fig. 2 an enlarged view of the Fig. 1 section X framed by a dot-dash line, in which a longitudinal section according to section line II-II is Fig. 4 shows a preferred embodiment of the image recording unit in its use position mounted on the outside of the process container, Fig. 3 the arrangement Fig. 2 in a plan view with view direction according to arrow III from Fig. 2 with only a dash-dotted indication of a housing of the image recording unit enclosing the relevant components of the image recording unit, Fig. 4 an axial front view of the image recording unit with view direction according to arrow IV of Fig. 2 and Fig. 5 an illustration relating to the granulation method according to the invention, wherein an image part (b) shows a diagram reproduced by an output device, which is a histogram in which the number "A" of the analysed granule particles is plotted against the particle diameter "D", while an image part (a) shows an image of the granules taken by the image recording unit, which forms the basis for generating the diagram according to image part (b).

[0050] From the Fig. Figure 1 shows a schematically illustrated granulation device 1, which is explained in more detail below. It has a preferred design and can be used to carry out a granulation process. The granulation device 1 can be operated with a granulation method, which is also described in more detail below, to carry out the granulation process.

[0051] The granulation device 1 has a granulation apparatus 2 which has a process container 3 which is, for example, box-shaped or drum-shaped and which has a container wall 5 enclosing an interior space referred to as the process chamber 4.

[0052] The process container 3 has a vertically downward-oriented container bottom 6 and an opposite, vertically upward-oriented container top 7. A vertical direction 8a of the process container 3, defined by the axial direction of a vertical axis 8, is indicated by a dot-dash line. In a normal operating position of the process container 3, the vertical axis 8 runs vertically.

[0053] The exemplary granulation apparatus 2 is a fluidization granulation apparatus, which has the property of transforming granules 11 currently undergoing a granulation process into a flowable, fluid state. The granulation apparatus 2 is preferably a fluidized-bed granulator 2a, in which the granules 11 located in the process chamber 4 are lifted and swirled during a granulation process by means of a process gas supplied according to flow arrows 14, so that a fluidized bed 15 is created in the process chamber 4. The fluidized-bed state is maintained as long as the process gas is fed into the process chamber 4.

[0054] Within the fluidized bed 15, the individual granulate particles 12 of the granulate 11, which are present in different sizes, are strongly swirled together and behave like a fluid.

[0055] With the granulation device 1, a granulation process can be carried out by appropriate operation, producing granules 11 consisting of a plurality of granule particles 12. The material composition of the granule particles 12 is based on the intended use, which is, for example, in the fertilizer sector and, in particular, in the pharmaceutical field. The produced granules 11 are used, for example, to produce fertilizer pellets or medicinally usable tablets.

[0056] A removal device 16, arranged particularly in the area of ​​the container bottom 6 on the process container 3, which has a removal opening 16a suitable for opening as needed, allows the produced granulate 11 to be removed for further use. For example, a tablet press can be connected to the removal device 16.

[0057] The granulation apparatus 2 contains a process gas inlet 17 arranged on the process container 3, through which the aforementioned process gas can be fed into the process chamber 4, particularly from below, according to the flow arrows 14. The process gas is, for example, an inert gas, preferably air. A motor-driven blower 18 arranged upstream of the process gas inlet 17 supplies the process gas inlet 17 and thus the process chamber 4 with process gas at a desired volume flow and gas pressure.

[0058] The process gas supplied for the granulation process is expediently tempered and, in particular, heated to a suitable temperature. In this way, the process gas can supply the thermal energy possibly required for the granulation process to the process chamber 4. For example, the process gas inlet 17 is equipped with a heat source 21, which may be a gas heater designed as a heat exchanger. However, the heat source 21 for heating the process gas can also be installed elsewhere, in particular upstream of the blower 18.

[0059] Furthermore, a process gas outlet 22 communicates with the process chamber 4, particularly in the area of ​​the container top 7, which serves to discharge the process gas supplied through the process gas inlet 17. As it flows through the process chamber 4, the process gas transfers the thermal energy required for the particle-technical process to the granulate 11 or its starting materials.

[0060] The granulation apparatus 2 is preferably a rotor granulator 2b, which applies to the illustrated embodiment. In this case, the granulation apparatus 2 has, according to the illustrated embodiment, a rotor 23a arranged in the process chamber 4 and rotatable by motor about a rotational axis 20 extending in the vertical direction 8a, with a rotor plate 23. An electrically actuated drive motor 24 is provided to generate the rotary movement of the rotor 23a, which is fastened to the process container 3 outside the container, particularly in the region of the container bottom 6. The rotor plate 23 extends in a plane perpendicular to the vertical axis 8 and is thus oriented horizontally, for example. It is located in a lower spatial region 4a of the process chamber 4 assigned to the container bottom 6.

[0061] The container wall 5 has a side wall 25, which is, for example, hollow-cylindrical in shape, which extends around the vertical axis 8 and laterally closes the process chamber 4 all around. An annular gap 26, illustrated enlarged in the drawing, is formed between the outer edge of the rotor plate 23 of the rotor 23a and the side wall 25. The process gas fed in below the rotor plate 23 via the process gas inlet 17 located there can flow upward through this gap.

[0062] By way of example, the rotor granulator 2b is a fluidized bed granulator 2a designed as a rotor fluidized bed granulator, in which the process gas flowing upwards through the annular gap 26 interacts with the granulate particles 12 in an upper space region 4b of the process space 4 located above the rotor plate 23 to generate a fluidized bed 15.

[0063] According to a non-illustrated embodiment of a fluidized bed granulator 2a usable for the invention, the rotor 23a is omitted and is replaced by a stationary sieve-like structure through which the process gas interacting with the granulate particles 12 located above is passed.

[0064] In another advantageous embodiment of the rotor granulator 2b, the process gas guided through the process chamber 4 past the rotor plate 23 according to the flow arrows 14 is used as a sealing gas, which in particular in the manner of a gas curtain prevents granulate particles 12 from falling through the annular gap 25 into the area below the rotor plate 23. Air is used in particular as the process gas. The actual granulation is caused by the granulate particles 12 being dispersed by the rotating rotor 23a in conjunction with Fig. 1, the blade-like structures 9, indicated by dash-dotted lines, are moved through the process chamber 4 in particularly toroidal granulate flows with continuous mixing. In particular, when the granulate 11 rolls against surfaces of the process container 3 and the rotor 23a, including the blade-like structures 9, granulate particles 12 with a high degree of roundness are formed.

[0065] The granulation device 1 is designed, by way of example, to carry out a granulation process that can be referred to as spray granulation. In this process, a granulation liquid provided in a liquid tank 27 of the granulation device 1 is sprayed into the process chamber 4 via a spray nozzle arrangement 28 located in the process chamber 4, according to the dotted lines 31. The spray nozzle arrangement 28 is connected to the liquid tank 27 via a motor-driven liquid pump 32 of the granulation device 1. During operation of the liquid pump 32, granulation liquid is sucked from the liquid tank 27 and sprayed into the process chamber 4 in a finely distributed manner, in particular with the addition of air to generate a fine spray mist.

[0066] The granulation device 1 can be used for spray granulation, in which the granules 11 are formed exclusively from the sprayed granulation liquid. A granulation liquid containing solids, for example a suspension, is sprayed into the process chamber 4. The aqueous components evaporate, and the remaining solids act as carrier cores, which are wetted with further granulation liquid, from which, after further evaporation, a solid shell is formed around the respective carrier core. This continuously repeated granulation process produces granulate particles 12 with an onion-like layer structure.

[0067] The granulation device 1 preferably offers the possibility of introducing a predefined quantity of suitable carrier cores into the process chamber 4 at the beginning of the granulation process. Here, the supplied granulation liquid is then used not for core formation, but only for layered particle growth. For example, the granulation device 1 is equipped with a suitable feed device 33, by means of which the carrier cores can be fed into the process chamber 4. The feed device 33 contains, for example, a motor-operated conveyor unit 34, for example in a configuration as a screw conveyor, and a carrier core storage unit 35 connected to the conveyor unit 34 and filled with a sufficient quantity of carrier cores during the granulation process.

[0068] The granulation device 1 can also be expediently used for a granulation process in which the granules are produced by spray agglomeration. Very small, powdery particles are agitated by the process gas in a fluidized bed and sprayed with a granulation liquid acting as a binder from the spray nozzle arrangement 28. A large number of particles are bonded to form agglomerates by forming liquid bridges, with the spraying process continuing until the agglomerates have reached the desired size for the granulate particles. The powdery particles can be introduced via the feed device 33.

[0069] In order to obtain granules 11 with a desired morphology, in particular a desired particle size, the operating state of an ongoing granulation process can be influenced by one or more variable operating parameters. For this influencing option, the granulation device 1 is provided with a Fig. 1 electronic control device 36 indicated by dashed lines.

[0070] The electronic control device 36 is electrically connected via control lines 37 indicated by dashed lines to those device components 38 of the granulation device 1 whose operating parameters are variable and which, for better differentiation, are also referred to as influenceable device components 38.

[0071] Electrical operating signals can be supplied to the controllable device components 38 via the control lines 37, which signals specify an operating state of the respective controllable device component 38.

[0072] By way of example, the granulation device 1 contains the blower 18, the heat source 21, the drive motor 24, the liquid pump 32 and the conveying unit 34 as controllable device components 38. Depending on the design, the granulation device 1 can have any sub-combination of these controllable device components 38 and / or further controllable device components 38.

[0073] On the blower 18 side, a variable operating parameter can be the volume flow, and on the heat source 21 side, the temperature of the process gas that can be fed in via the process gas inlet. On the drive motor 24 side, a variable operating parameter can be the speed of the rotor 23a. On the liquid pump 32 side, the variable operating parameters can be the volume flow and / or the spraying time and / or the droplet size of the granulation liquid. On the feed device 33 side, the variable operating parameters can be, for example, the quantity of carrier cores that can be fed into the process chamber 4.

[0074] By appropriately controlling the controllable device components 38, the residence time of the granulate particles 12 in an ongoing granulation process, also referred to below as the processing time, can also be expediently influenced. If the granulation process is carried out as a batch process according to the illustrated embodiment, the processing time can be influenced, for example, by shutting down the granulation process, which can be achieved, for example, by deactivating the controllable device components 38.In particular in this context, there is the advantageous possibility of designing the removal device 16 in a motor-operated design and also connecting it to the electronic control device 36 via a further control line 37 (not shown), so that it also forms an influenceable device component 38, by the actuation of which the produced granulate can be removed from the process chamber 4 as required.

[0075] It is understood that the granulation device 1 can alternatively be designed to carry out a continuous granulation process. In this case, the resulting granulate portions are continuously removed from the process chamber 4 upon reaching the desired properties, in particular a desired particle size, and replaced with newly produced granulate particles, for example, by continuously supplying carrier cores. The processing time results from the residence time of the granulate particles 12 in the process chamber 4.

[0076] The granulation device 1 is equipped with an electrically controllable image recording unit 42, with which two-dimensional images of the process chamber 4 and thus of the granulate 11 currently undergoing a granulation process in the process chamber 4 can be taken during a granulation process. These two-dimensional images can be evaluated by the electronic control device 36 in order to be used to specify the operating parameters of the granulation device 1, in particular to change the operating parameters for the purpose of modifying the operating state of the granulation process. An electrical communication line 43, indicated by dashed lines, enables the necessary data transmission from the image recording unit 42 to the electronic control device 36.For example, the electrical communication line 43 is implemented using an electromechanical connecting device 44 of the image recording unit 42, which has a plug connector to which a connecting cable leading to the electronic control device 36 can be connected.

[0077] The electrical communication line 43 enables bidirectional data traffic. Thus, the operation of the electrically controllable image acquisition unit 42, in particular its image acquisition processes, can be controlled by the electronic control device 36. Control options exist, in particular, with regard to the frequency of image acquisitions, the time interval between consecutive image acquisitions, and / or the exposure duration.

[0078] The ability to capture images of the interior of process chamber 4 offers the significant advantage of capturing images of the granules undergoing a granulation process in process chamber 4 inline, i.e., directly during particle growth. This allows for at least near-real-time monitoring of the process flow, which in turn allows for immediate interventions to modify the process flow as needed.

[0079] Preferably, an automated image acquisition initiated by the electronic control device 36 takes place continuously throughout the process. If the process does not conform to the standard, the electronic control device 36 initiates an immediate modification by influencing one or more operating parameters. Removing granulate particles from the ongoing granulation process for analysis is not necessary with the described setup and is also not performed with the described method.

[0080] The image recording unit 42 contains an optoelectrical assembly 45, which is expediently constructed in the manner of a camera and defines an optical axis 46. The optoelectrical assembly 45 contains an image sensor 47 and a lens 48 positioned upstream of the image sensor 47 in the axial direction of the optical axis 46. The image sensor 47 is a component of a sensor unit 49 integrated into the optoelectrical assembly 45, which, in addition to the image sensor 47, also comprises further electronic and / or mechanical components.

[0081] The optical assembly 45 is mounted on a support structure 51 of the image recording unit 42, via which the image recording unit 42 is fastened to the granulation apparatus 2 in its illustrated use position. On a front side 52 oriented in the axial direction of the optical axis 46, the image recording unit 42 has a fastening interface, referred to as an image recording unit fastening interface 53 for ease of differentiation, which is adapted to a further fastening interface arranged on the process container 3 of the granulation apparatus 2 and referred to as a container fastening interface 54, such that the image recording unit 42 can be fastened or is fastened to the outside of the process container 3 by the interaction of the two fastening interfaces 53, 54, in a particularly detachable manner, while assuming a use position.

[0082] The container fastening interface 54 is located, for example, on an outer surface 55 of the container wall 5 facing away from the process chamber 4, and preferably on the side wall 25. It contains, for example, a fastening ring 54a that is welded or screwed to the outer surface 54 of the side wall 25. The image recording unit fastening interface 53 contains a fastening flange 53a that has through holes that are aligned with threaded holes in the fastening ring 54a. The fastening flange 53a is a component of the support structure 51. By means of several fastening screws 56 that are inserted into the through holes of the fastening flange 53a and screwed into the threaded holes of the fastening ring 54a, the fastening flange 53a and thus the support structure 51 and consequently the entire image recording unit 42 are detachably fastened to the container wall 5.Here, the optical assembly 45 assumes a position in which the optical axis 46 passes through the container wall 5, for example the side wall 25, in the fastening area 57 defined by the two cooperating fastening interfaces 53, 54 in the illustrated embodiment, in particular at a right angle.

[0083] The image recording unit 42 has a longitudinal shape with a longitudinal axis 62, which, for example, has the same orientation as the optical axis 46.

[0084] The image pickup unit 42 has on its front side 52 a light entry opening 58 aligned with the optical axis 46, which is expediently covered by a translucent and, in particular, transparent front glass 61, which is made, in particular, of borosilicate glass. The front glass 61 is fixed to the support structure 51 in a preferably replaceable manner by a retaining ring 63, which is, for example, screwed to the mounting flange 53a and which, in the use position of the image pickup unit 42, comes to rest between the mounting ring 54a and the mounting flange 53a. It expediently rests against the outer surface 55 or is only minimally spaced from it.

[0085] The lens 48 is located between the light entry opening 58 and the sensor unit 49, being spaced from the light entry opening 58.

[0086] In the area of ​​the container attachment interface 54, where the optical axis 46 runs, the container wall 5 is transparent. There, it has a transparent wall section 64, which allows an unobstructed view from outside the process container 3 into the process chamber 4 and thus of the granulate 11 currently located therein. The light entry opening 58 is positioned adjacent to the transparent wall section 64. In this way, the image recording unit 42 is able to take images of the process chamber 4 through the transparent wall section 64 and thus also of the granulate 11 currently undergoing a granulation process in the process chamber 4.By way of example, the transparent wall section 64 is formed by a transparent viewing window 64a made of glass or plastic, which, in particular, is integrated, comparable to a porthole, into an opaque wall section 65 of the container wall 5, which, by way of example, forms the remaining container wall 5. The transparent wall section 64, like the remaining areas of the container wall 5, is designed to be gas-tight.

[0087] The optoelectric assembly 45, in particular the lens 48, defines a focal plane 66, also referred to as the sharpness plane, which lies in the space of the objects to be imaged—here: the granulate particles 12—and whose points are sharply imaged on an image plane defined by the image sensor 47. Preferably, the image recording unit 42 is equipped with a positioning device 67 that allows variable positioning of the focal plane 66 in order to position the focal plane 66 in the process chamber 4 so that it lies where the granulate particles 12 are to be optically detected. Preferably, the focal plane 66 is positioned in the process chamber 4 in the immediate vicinity of the inner surface 68 of the container wall 5 opposite the outer surface 55, so that the outer granulate particles 12 of a fluidized bed 15 moving past are always sharply imaged.

[0088] The positioning device 67 allows adjustment of the optoelectric assembly 45 as a whole, while maintaining the relative position between the image sensor 47 and the lens 48.

[0089] An electrically actuated linear module 71 is provided as an example for the positioning device 67. The module has a stator 71a fastened to the support structure 51 and a slider 71b that can be moved linearly back and forth relative to it while executing a positioning movement 70 indicated by a double arrow. The optoelectrical assembly 45 is fastened to the slider 71b. The slider 71b is particularly designed in the manner of a slide. An electric drive motor 72 of the linear module 71, which cooperates with the slider 71b for driving purposes, is connected via an electrical line 69 to the electromechanical connecting device 44 and consequently via the electrical communication line 43 to the electronic control device 36, via which the desired positioning of the focal plane 66 for adjusting the focus range is thus possible.

[0090] Preferably, the lens 48 is designed as a telecentric lens 48a. Preferably, the telecentric lens 48a has object-side telecentricity, with a bi-telecentric lens 48a having both object-side and image-side telecentricity being provided, for example.

[0091] The use of a telecentric lens 48a offers the advantage of maintaining a constant image scale in the focal plane 66, with one pixel (px) consistently corresponding to a specific unit of length. This offers significant advantages for image analysis due to simple conversion. Thus, the particle size is defined when the image area is in focus. The inherently shallow depth of field of, for example, 1 mm can be easily compensated for by the positioning option via the positioning device 67, while maintaining a fixed focal length. Calibration or recalibration measures for carrying out the granulation process or method are unnecessary.

[0092] The sensor unit 49 is expediently equipped with a global shutter, which is of high quality because it can close very quickly. During the granulation process, images of the granulate particles 12 moving past the focal plane 66, sometimes at very high speed, are taken by the image recording unit 42 in a time sequence predetermined by the electronic control device 36. This allows for the occurrence of motion blur to be reduced to a negligible level by short exposure times. Power is preferably supplied via PoE ("Power over Ethernet"), since this allows significantly longer cable lengths compared to USB connections, which proves to be particularly advantageous when integrated into larger granulation systems.

[0093] Image sensor 47, for example, is a CCD sensor or a sensor based on CMOS technology. The pixel size is 4.5 µm, for example, resulting in a good ratio between pixel size or sensor resolution and light sensitivity.

[0094] In the exemplary embodiment, the telecentric lens 48a used has a magnification of 0.735 and a depth of field of approximately 1.1 mm. This results in an effective pixel size of approximately 6.12 µm per pixel. In principle, however, other lens parameters are also possible, for example, a magnification of 1.0 in conjunction with a depth of field of approximately 0.6 mm and a resulting effective pixel size of approximately 4.5 µm per pixel. Due to a smaller aperture cross-section, the latter would, however, deliver somewhat less light to the image sensor 47.

[0095] For optimal positioning of the optoelectric assembly 45, the image recording unit 42 is expediently equipped with at least one position sensor 73, which is attached, for example, to the stator 71a and responds to the rotor 71b. The position sensor 73, which can be a limit switch, for example, is expediently also connected to the electronic control unit 36 ​​via the electrical communication line 43.

[0096] The optoelectrical assembly 45 is conveniently attached to the positioning device 67 and, for example, to its slider 71b using a suitable attachment adapter 74.

[0097] The functionally relevant components of the image acquisition unit 42 are expediently housed in a housing 75 of the image acquisition unit 42 and are expediently enclosed by this housing 75, thus shielding them from the environment. The housing 75 is, for example, fixed to the support structure 51 and has a tubular structure, for example. Alternatively, the housing 75 can be a direct component of the support structure 51.

[0098] The image capture unit 42 is expediently equipped with an illumination device 76, which enables illumination of the area to be photographed, in particular the focal plane 66, in order to achieve high-quality images. For example, the illumination device 76 includes a ring light 76a arranged coaxially to the optical axis 46, which is preferably positioned in the region of the light entry opening 58 and there, in particular, directly behind the optional front glass 71.

[0099] The ring light 76a provides homogeneous illumination of the focal plane 66. The ring light 76a has a central through-opening through which the image information to be recorded can pass.

[0100] It is advantageous if the central aperture of the ring light 76a is larger than the lens diameter. This allows the ring light 76a to be offset by 20 mm to 50 mm for particularly homogeneous illumination. Sensor unit 49 and lens 48 can be relocated approximately 20 mm further toward the front side 52, so that the focal plane 66 is at a greater distance from the front side 52 of the image acquisition unit 42 and lies within the process chamber 4, even with a high glass thickness of the viewing window 64a.

[0101] Preferably, the ring light 76a is at least partially enclosed in a heat sink 77 that surrounds it, ensuring optimal heat dissipation. In this way, a ring light 76a with high light intensity can be used.

[0102] In principle, it is advantageous if the lighting device 76 is implemented using LED technology, with the ring light 76a being an LED ring light by way of example.

[0103] The electronic control device 36, which is suitable for at least largely automated operation and is referred to simply as control device 36 for the sake of simplicity, has a particularly advantageous structure in the illustrated embodiment, which is explained in more detail below.

[0104] The control device 36 contains an electronic data processing device 78, which is designed for image processing of the images captured by the image recording unit 42. The data processing device 78 is further provided to actuate the image recording unit 42 and, in particular, to command the desired image recordings, preferably in the form of image sequences with image recordings taken immediately one after the other.

[0105] The data processing device 78 communicates with an electronic operating state setting device 81, which also belongs to the control device 36. The electronic operating state setting device 81, in turn, is connected to the controllable device components 38 of the granulation device 1 via the signal lines 37 already mentioned above. Via the signal lines 37, the operating state setting device can transmit electrical operating signals to the controllable device components 38, which are generated in the operating state setting device 81 on the basis of electronic setting signals that are supplied to the operating state setting device 81 by the data processing device 78 according to arrow 81a.

[0106] The data processing device 78 further communicates with an electronic output device 82, which preferably has a display device 82a, which is in particular a display and which is designed, for example, as a monitor.

[0107] For external influence, the control device 36 is expediently equipped with an input device 83, which communicates, for example, with the data processing device 78. For example, the input device 83 allows for parameterization of the control device 36 and, for example, also for manual training of an artificial intelligence (AI) 84 (only symbolically indicated), with which the electronic control device 36 is preferably equipped.

[0108] The input device 83 can be designed for remote input by means of digital instruments and / or for manual keyboard input.

[0109] For controlled operation in a closed control loop, the control device 36 expediently has a schematically indicated electronic control device 85, which is preferably - like the artificial intelligence 84 - integrated into the electronic data processing device 78.

[0110] In a preferred operation of the granulation device 1, a granulation process is carried out in which images of the process chamber 4 are taken by means of the image recording unit 42, which is initiated by the data processing device 78, which Fig. 1 is indicated by an arrow at 86. The image is captured inline, i.e., while a granulation apparatus 2 is in operation during the granulation process, specifically through the transparent wall section 64 of the container wall 5. The image is captured in the focal plane 66, thus, for example, in the outer boundary layer of the fluidized granules 11. Each image capture represents a snapshot of the granule particles 12 moving past the light entrance opening 58 at high speed.

[0111] In the picture part (a) of the Fig. Figure 5 schematically illustrates an image 42a taken by the image acquisition unit 42, with the photographed granulate particles 12 shown in a framed section, greatly enlarged for clarity. The image 42a contains granulate particles 12 both in the focal plane 66 and located behind it.

[0112] The images captured by the image acquisition unit 42 are transmitted sequentially during the granulation process via the communication line 43 to the data processing device 78, where an electronic image analysis is performed. Within the scope of this image analysis, the data processing device 78 calculates granule-related result values ​​for process-specific parameters, which in particular are one or more parameters from a parameter group that includes the average particle diameter of the granulate particles 12, the size distribution of the granulate particles 12, and the mean value of the particle diameters.

[0113] In this evaluation, however, only those granulate particles 12 are taken into account, if possible, which are located in the focal plane 66 in the respective image recording 42a. Such granulate particles 12 are referred to as reference granulate particles 12a for better differentiation and are shown in the image recording 42a in Fig. 5(a) is additionally indicated by a dashed contour line. For the reference granule particles 12a located in the focal plane 66, the image scale is known due to the optical design of the optoelectric assembly 45 explained above, so that the granule dimensions can be very easily calculated based on the pixel size according to the actual conditions.

[0114] The identification of the reference granulate particles 12a for the subsequent evaluation is possible, for example, by taking into account the degree of sharpness of the image, since with the telecentric lens 48a used, the granulate particles 12 lying outside the focal plane 66 are imaged much less sharply than the granulate particles 12 lying in the focal plane 66. The shape of the photographed granulate particles 12 can also be used as a selection criterion, based on the fact that granulate particles 12 lying in the focal plane are not obscured and therefore have a uniform and usually approximately circular outline, while granulate particles 12 lying behind them are partially obscured and consequently have striking inconsistencies in their outlines.

[0115] Using artificial intelligence (AI) 84, the aforementioned selection process can be carried out particularly quickly and precisely. A key factor in this is, among other things, training the artificial intelligence 84 to ensure the most error-free recognition of the reference granulate particles 12a. This training is achieved, in particular, by manually labeling images taken during a granulation process or images of a granulate 11 input via a correspondingly configured input device 83 as reference granulate particles 12a using a labeling medium, such as a computer mouse. With increasing training time, the AI ​​84 can reliably recognize the reference granulate particles 12a during real operation of a granulation process.

[0116] The data processing device 78, particularly using the AI ​​84, is capable of calculating the granule-related result values ​​discussed above from the identified reference granulate particles 12a. For example, the identified reference granulate particles 12a can be electronically measured with respect to their particle size, and in particular with respect to their circumference. For example, the software creates a closed outline around the identified reference granulate particles 12a - in the Fig. 5(a) with dashed contour lines – and calculates the particle circumference, taking into account the underlying image scale – for example, an effective pixel size of 6.12 µm per pixel. From this value, a particle diameter can then be calculated, which represents a particle size.

[0117] Every granulation process is based on the objective of producing granules 11 with specific properties or a specific quality, in particular granules 11 with granule particles 12 of a specific particle diameter "D." Since a granulation process inevitably produces granule particles 12 with differing particle diameters "D," the goal is generally to produce the granules 11 with granule particles 12 of a predetermined average particle diameter "M," i.e., a mean diameter value that corresponds at least to a target value. In any case, the granulation process should be carried out in such a way that the calculated granule-related result values ​​correspond as closely as possible to the specified target value(s).

[0118] The target values ​​are stored or can be stored as comparison values ​​in the data processing device 78. For example, the input device 83 enables the input of one or more target values ​​for the granule-related result values.

[0119] In the control device 85, which can be implemented as a component of the artificial intelligence 84, a comparison takes place during the granulation process between the granule-related result values ​​calculated by the data processing device 78 and the previously stored target values. Depending on the comparison result, the aforementioned electrical adjustment signals are generated and fed as input signals to the electronic operating state adjustment device 81 as indicated by arrow 81a. Thus, within the control loop, the granule-related result values ​​function as the controlled variable, the target values ​​as the reference variable, and the adjustment signals as the manipulated variable for adjusting the variable operating parameters.The operating state setting device 81 is designed in such a way that it can generate operating signals based on the received setting signals and output them in a correctly assigned manner to the connected controllable device components 38 so that the operating parameters are modified in order to optimize the granulate-related result values.

[0120] The output device 82 is, for example, capable of displaying at least granulate-related result values ​​according to the previous calculation of the data processing device 78, which is also advantageously done during the granulation process. Fig. 5(b) shows, by way of example, the visualization of a histogram carried out by the output device 82, which shows the size distribution of the granulate particles - here: the number "A" of granulate particles over the particle diameter "D" - based on a Fig.5(a). Also displayed is an average value "M" of all particle diameters "D" underlying the image evaluation. The display can be shown separately for each image acquired by the image acquisition unit 42 or, in turn, as an average of the average values ​​of several consecutively acquired images. For example, images can be evaluated at regular intervals and combined to form a growth curve across the process and visualized.

[0121] Preferably, the control device 36 has a mechanically or software-implemented selector switch with which the type of granulate-related result values ​​or other process-related information that can currently be output by the output device 82 can be selected.

[0122] Insofar as electrical cable connections are mentioned in connection with the networking of the individual device components, wireless transmission systems can also be used as an alternative, in particular radio-based ones.

[0123] In a preferred artificial intelligence (AI) 84, which is also used in the illustrated embodiment, Mask R-CNN is used as the algorithm. This is a convolutional neural network, or a convolved neural network with masks, which is particularly well suited for image analysis. When used, an image of the granulate particles 12 to be examined is input. After evaluation, particle-specific dimensions such as circumference, area, and / or diameter are output. These dimensions are then further processed as a data set, for example, to obtain statistical values ​​about the particle diameters.

[0124] The convolutional network contains a feature extractor and a classifier. The feature extractor can generate an RPN (“Region Proposal Network”), which divides the captured image into regions and assigns a probability value to these regions. Regions of Interest (ROIs) are generated using these regions—regions can be merged for this purpose—and an assessment is created regarding the probability of object detection of the detected object class, a bounding box (a rectangular frame around the detected particle contour), and a mask as a marked object region. The quantity, diversity, and quality of the training data used to train the neural network are particularly important for the quality of the marked object region or the detected object, i.e., a granular particle. This training data is created manually, and input device 83 is available.For example, the neural network used can be a pre-trained neural network, such as is already available for other analysis purposes, which is then appropriately adapted by further training measures to carry out the granulation process.

[0125] The duration of a granulation process depends on the degree of agreement between the granule-related result values ​​and the target values. As soon as an acceptable agreement is reached, the granulation process is expediently aborted or interrupted. The verification required for this can be performed software-based using the data processing device 78 or, alternatively or additionally, by monitoring by an operator while observing the display device 82a. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] DE 100 61 085 A1

[0002] WO 2019 / 091507 A1

[0003]

Claims

[1] Granulation process for producing a granulate (11) consisting of a plurality of granulate particles (12), wherein a granulation process accompanied by particle growth is carried out in a process chamber (4) of a process container (3) delimited by a container wall (5), which granulation process is monitored using an electrically controllable image recording unit (42) with which two-dimensional images of the granulate (11) are taken, which are then evaluated by means of an electronic control device (36) and, after their evaluation, are used to specify variable operating parameters influencing the operating state of the granulation process, characterized by that the images are taken as inline images during the granulation process of the granulate (11) in the process chamber (4) during particle growth. [2] Granulation process according to claim 1, characterized bythat the images of the granulate (11) located in the process chamber (4) are taken from outside the process chamber (4) through a transparent wall section (64) of the container wall (5) of the process container (3). [3] Granulation process according to claim 1 or 2, characterized by that by means of the electronic control device (36) an image processing of the images recorded by the image recording unit (42) is carried out, by means of which a calculation of granulate-related result values ​​such as in particular an average particle diameter and / or a size distribution of the granulate particles (12) and / or a mean value of the particle diameter is carried out, wherein on the basis of the granulate-specific result values ​​setting signals are generated by means of which the variable operating parameters influencing the operating state of the granulation process are predetermined. [4] Granulation process according to claim 3, characterized bythat the setting signals are generated by means of a control based on a comparison between the granulate-related result values ​​and specified target values. [5] Granulation process according to claim 3 or 4, characterized by that image processing is carried out such that, for the calculation of the granulate-related result values, those granulate particles (12) visible in the recorded images are identified as reference granulate particles (12a) which lie in a focal plane (66) of the image recording unit (42), wherein only these identified reference granulate particles (12a) are used as a basis for the calculation of the granulate-related result values ​​and for this purpose are preferably measured electronically with regard to their particle size, in particular their circumference. [6] Granulation process according to one of claims 1 to 5, characterized bythat it is carried out by means of a granulation device (1) which has a granulation apparatus (2) which has the process container (3) delimiting the process space (4), wherein the image recording unit (42) for carrying out the process is arranged in the region of the granulation apparatus (2) in such a way that it can produce the images of the process space (4) during a granulation process and thus the inline images of the granulate (11) undergoing a granulation process in the process space (4). [7] Granulation process according to claim 6, characterized by that it is carried out by means of a granulation device (1) whose granulation apparatus (2) is a fluidization granulation apparatus which causes fluidization of the granules (11) during the granulation process. [8] Granulation process according to claim 6 or 7, characterized bythat it is carried out by means of a granulation device (1) whose granulation apparatus (2) is a fluidized bed granulator (2a) which creates a fluidized bed (15) of the granules (11) during the granulation process. [9] Granulation process according to one of claims 6 to 8, characterized by that it is carried out by means of a granulation device (1), the granulation apparatus (2) of which is a rotor granulator (2b) equipped with a rotor (23a) which is motor-driven to rotate during the granulation process, in particular a rotor fluidized bed granulator, wherein the rotor (23a) used expediently has a rotor plate (23) arranged in the process space (4). [10] Granulation process according to claim 9, characterized by that a variable operating parameter of the granulation process is the speed of the rotor (23a). [11] Granulation process according to one of claims 1 to 10, characterized by that a variable operating parameter of the granulation process is the residence time of the granulate particles (12) in an ongoing granulation process, which can be specified in particular by switching the granulation process on and off. [12] Granulation process according to one of claims 1 to 11, characterized by that it is carried out by means of a granulation apparatus (2) which has on the process container (3) a process gas inlet (17) which communicates with the process chamber (4) and is used to feed in a process gas, and a process gas outlet (22) which also communicates with the process chamber (4) and is used to discharge the fed-in process gas. [13] Granulation process according to claim 12, characterized by that a variable operating parameter of the granulation process is the volume flow and / or the temperature of the process gas fed in via the process gas inlet (17). [14] Granulation process according to one of claims 1 to 13, characterized by that it is carried out by means of a granulation apparatus (2) which has a spray nozzle arrangement (28) used to spray a granulation liquid into the process space (4) of the process container (3). [15] Granulation process according to claim 14, characterized by that a variable operating parameter of the granulation process is the volume flow and / or the injection time and / or the droplet size of the granulation liquid. [16] Granulation process according to one of claims 1 to 15, characterized by that it is carried out by means of a granulation apparatus (2) which has a feeding device (33) which is used during the process to feed carrier cores, in particular in powder form, into the process space (4) which form the basis of the granulate structure. [17] Granulation process according to claim 16, characterized by that a variable operating parameter of the granulation process is the quantity of carrier cores that can be fed into the process chamber (4). [18] Granulation process according to one of claims 1 to 17, characterized by that a process container (3) is used, the container wall (5) of which has at least one transparent wall section (64), wherein the image recording unit (42) for carrying out the process is arranged in the region of the transparent wall section (64) outside the process space (4) and wherein images of the process space (4) and thus of the granulate (11) located therein are produced with the image recording unit (42) through the transparent wall section (64). [19] Granulation process according to claim 18, characterized bythat the transparent wall section (64) of the container wall (5) is a transparent viewing window (64a), in particular made of glass, enclosed by an opaque wall section (65) of the container wall (5). [20] Granulation process according to claim 18 or 19, characterized by that the image recording unit (42) is fastened to the outside of the process container (3) at least during the process implementation, wherein a container fastening interface (54) adapted to the image recording unit (42) is expediently arranged on the outside of the container wall (5) of the process container (3). [21] Granulation process according to one of claims 1 to 20, characterized bythat the image recording unit (42) used has an image recording unit fastening interface (53) enabling its stationary fixation with respect to the process container (3) and an electromechanical connecting device (44) for electrical connection to the electronic control device (36). [22] Granulation process according to one of claims 1 to 21, characterized by that the image recording unit (42) used is equipped with an optoelectric assembly (45) having an image sensor (47) and a lens (48), wherein the lens (48) is expediently a telecentric lens (48a) which is preferably bi-telecentric. [23] Granulation process according to claim 22, characterized bythat the image recording unit (42) is placed such that a focal plane (66) defined by the lens (48) lies in the process space (4) and is expediently arranged there adjacent to an inner surface (68) of the container wall (5) of the process container (3). [24] Granulation process according to claim 22 or 23, characterized by that the image recording unit (42) used is equipped with a positioning device (67) which enables a variable positioning of the optoelectrical assembly (45) causing a change in the position of a focal plane (66) of the lens (48) and which expediently has an electrically actuable linear module (71) carrying the optoelectrical assembly (45). [25] Granulation process according to one of claims 1 to 24, characterized bythat the image recording unit (42) used has an illumination device (76), in particular having a ring lamp (76a), which is used during the process to illuminate the area to be imaged within the process space (4). [26] Granulation process according to one of claims 1 to 25, characterized by that the image recording unit (42) is connected to the electronic control device (36) for carrying out the method and is controlled with regard to the image recording processes by means of electronic image recording commands generated by the electronic control device (36). [27] Granulation process according to one of claims 1 to 26, characterized bythat the electronic control device (36) used contains an electronic data processing device (78) with which an image processing of the images recorded by the image recording unit (42), in particular in image sequences, is carried out and with which a calculation of granulate-related result values ​​such as in particular an average particle diameter of the granulate particles (12) and / or a size distribution of the granulate particles (12) and / or an average value of the particle diameters is carried out. [28] Granulation process according to claim 27, characterized bythat by means of the electronic data processing device (78) image processing is carried out in such a way that, for the calculation of granulate-related result values, the granulate particles (12) lying in a focal plane of the image recording unit (42) are identified as reference granulate particles (12a) from the granulate particles (12) visible in the recorded images, and only these identified reference granulate particles (12a) are used as the basis for the calculation of the granulate-related result values, wherein they are expediently measured electronically with regard to their particle size, in particular their circumference. [29] Granulation process according to claim 27 or 28, characterized bythat an electronic control device (36) is used which contains an electronic operating state setting device (81) by means of which the variable operating parameters influencing the operating state of the granulation process are set based on the setting signals provided by the electronic data processing device (78) on the basis of the granulate-related result values. [30] Granulation process according to claim 29, characterized bythat an electronic control device (36) is used which contains a control device (85) which is designed in particular as a component of the electronic data processing device (78), by means of which the setting signals for the electronic operating state setting device (81) are generated based on a comparison between the granulate-related result values ​​calculated by the data processing device (78) and previously stored setpoint values ​​within the framework of a control, wherein the setpoint values ​​can expediently be predetermined individually by prior input by means of an input device (83) of the electronic control device (36). [31] Granulation process according to one of claims 1 to 30, characterized bythat an electronic control device (36) is used which contains an electronic output device (82) by means of which the granulate-related result values ​​calculated by the electronic data processing device (78) can be output, wherein the electronic output device (82) in particular contains a display device (82a) for visualizing the result values ​​and wherein the electronic output device (82) can expediently also output further process-related information. [32] Granulation process according to one of claims 1 to 31, characterized by that an electronic control device (36) is used which is equipped with an artificial intelligence (84) which is implemented in particular using a convolutional neural network.

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