Granulation method

Abstract

The invention relates to a granulation method used to produce a granulate (11) consisting of a plurality of granulate particles (12). During execution of the granulation method, a granulation process involving particle growth is carried out in a process chamber (4) of a process container (3), said chamber being delimited by a container wall (5), and is monitored using an electrically controllable image-capturing unit (42). During this monitoring process, two-dimensional images of the granulate (11) are captured using the image-capturing unit (42), are subsequently evaluated by means of an electronic control device (36), and, after being evaluated, are used to define variable operating parameters that influence the operating state of the granulation process. It is essential that the images are captured as inline image captures during the ongoing granulation process of the granulate (11) undergoing particle growth in the process chamber (4).

Description

[0001] Granulation process

[0002] 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.

[0003] A granulation process of the aforementioned type is known from DE 100 61 085 A1 and is carried out there by means of a granulation device which has a granulation section containing a granulation drum, downstream of which is a drop shaft having a funnel which is continuously supplied on the inlet side in a vertical direction with granulate particles produced in the granulation section. The granulate particles obtained in this way can be removed from a sampling opening in 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 being recorded, the color camera determines the grain size and the grain size distribution according to 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, for example in the form of a monitor. The processing unit also determines process-specific parameters which serve as input variables for a system controller which has fuzzy logic modules. After a comparison with setpoints, output signals are generated in order to influence the operating parameters of the granulation process in order to achieve the desired product quality. The image sequences can be recorded not only in a field unit but also directly on the granulate particles falling from the granulation section into the drop chute. Fertilizers and pharmaceutical products, for example, can be produced using this well-known granulation process.

[0004] WO 2019 / 091507 A1 describes a method for producing granular solid particles, wherein 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 takes place after they leave a process container in which a granulation process has taken place and which is provided, for example, with a granulation plate, the rotational movement of which causes a build-up agglomeration of a supplied 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 which can be used to influence the supply of starting substances for the granulation process.

[0005] 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, wherein an operator takes samples from the production plant at certain intervals during the granulation process using a sampler and examines the results outside the process plant with the aid of a microscope or camera. A small number of the particles taken are measured manually and, if necessary, analyzed with the aid of system software. The further management of the process 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.

[0006] The invention is based on the object of taking measures that allow for rapid analysis of the granulation process during the process, so that granules of high product quality can be produced reliably and reproducibly. This object is achieved with a granulation method in which, in conjunction with the method mentioned above, the images are taken as inline images of the granules in the process chamber during particle growth during the granulation process.

[0007] According to the invention, the granulation process, which takes place in particular in a granulation device, is monitored inline, i.e. directly in the process chamber during ongoing granulation, with the granulate particles growing in size being observed. During the granulation process, the images are taken as inline images of the granulate particles growing 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 take place by examining a large quantity of particles, unlike with sampling which only takes place from time to time, the achievable analysis result is considerably 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 supplied by an image recording unit that is positioned in the granulation process area in such a way that, during an ongoing granulation process, two-dimensional (2D) images can be taken of the interior of the process chamber and thus of the granules currently undergoing a granulation process. During these so-called inline image recordings, the granulation process proceeds undisturbed. The image recording unit can, for example, be placed 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. Following 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 influence with very short reaction times.With the help of inline image recordings, which are used in particular 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 the particle size, the grain size distribution, the 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 preselectable and preferably adaptable to the production speed image sequences. The type of variable operating parameters responsible for and influenceable for the operating state of the granulation process concern, for example, the temperature, volume flow rates and / or the 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 is to be understood as a reference to one or more variable operating parameters. Advantageous developments of the invention are evident from the subclaims.

[0009] 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.

[0010] It is advantageous if the electronic control device performs image processing of the images captured by the image acquisition unit, within the scope of 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 by which variable operating parameters are specified that influence the operating state of the granulation process.

[0011] Preferably, the adjustment signals are generated by means of a closed-loop control system based on a comparison between, on the one hand, the granulate-related result values ​​and, on the other hand, specified target values. This is advantageously carried out in a closed-loop control system.

[0012] The granulation process expediently performs image processing such that, for the calculation of the granule-related result values, only those granule particles visible in the captured images are identified as reference granule particles that lie within a focal plane of the image recording unit, whereby 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 electronically measured, preferably with regard to their particle size, in particular their circumference.

[0013] 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.

[0014] The granulation apparatus used to carry out the process can, in principle, be based on any desired functional principle. A design of the granulation apparatus as 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 design as a fluidized bed granulator is particularly useful in this context, in particular for carrying out spray granulation, spray agglomeration, spray coating or spray encapsulation. The process gas here contributes to the granules being swirled inside the process container, forming a so-called fluidized bed. For special requirements, spouted bed technology can be used.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 apparatus 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.

[0015] 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, is passed through the process container past the rotor and is used primarily or exclusively as a barrier gas, while the actual granulation is brought about 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 container, in particularly toroidal granulate streams with continuous mixing. When the granulate rolls along the surfaces of the process container and the rotor, including the blade-like structures, granulate particles with a high degree of roundness are produced.

[0016] The granulation apparatus used to carry out the process can, for example, be designed for so-called high-shear granulation. High-shear granulation is a shaping process for granulation in which a binder liquid is added to powdered particles in a closed process container containing mixing tools and a chopper. The mixing tools expediently include a motor-driven rotor, so that the granulation apparatus can in turn be referred to as a rotor granulator. Dense granules are formed via the resulting liquid and solid bridges.

[0017] 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 appropriate control of an associated electric drive motor.

[0018] In a preferred embodiment of the granulation process, 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 predetermined, 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 process, the processing time can be predetermined, for example, by an electronic control device provided for evaluating the two-dimensional images recorded by the image recording unit.

[0019] 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 also to a process gas outlet for discharging the process gas. The process gas is, for example, heated air or a heated inert gas. The process gas causes, for example, a drying of the substances in the process chamber and thus brings about, for example, a granulate build-up 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 granulate particles from falling downwards between the rotating rotor and the vessel 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 images taken.

[0020] To carry out spray granulation, the granulation apparatus used is expediently equipped with a spray nozzle arrangement which enables a granulation liquid to be sprayed into the process space of the process vessel. When carrying out the granulation process, it is thus possible to spray liquids containing solids, such as solutions, suspensions or melts, into the process space where the liquid components evaporate due to a high heat exchange with a process gas and the remaining solids form small particles as carrier cores which are wetted with another liquid so that after further evaporation a solid shell is formed around the carrier core. Since this process is constantly repeated, there is continuous growth of the granulate particles layer by layer.In an alternative spray agglomeration process, very small, powder-formed particles are moved in a fluidized bed created by a process gas and sprayed with a binder liquid from the spray nozzle arrangement. Here, 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.

[0021] In the presence of a spray nozzle arrangement, 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.

[0022] To carry out the process, a granulation apparatus equipped with a feed device is preferably used, with which the carrier cores underlying the granulate structure, particularly in powder form, can 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.

[0023] Depending on the design of the granulation device, the images of the granulate can be taken by the image recording unit using an image recording unit located directly in the process chamber or using an image recording unit located outside the process chamber. For safety reasons, particularly explosion protection, an image recording unit located outside the process container is generally preferred. In this case, the container wall of the process container expediently has at least one transparent wall section, in the area of ​​which the image recording unit is located outside the process chamber, the images of the process chamber and thus the inline images of the granulate located therein being taken from outside the process chamber through the transparent wall section.

[0024] 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.

[0025] 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.

[0026] An image recording unit located outside the process chamber and therefore externally can be attached to a separate support structure independently 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, which is matched to the structure of the image recording unit and to which the image recording unit is fastened in a position of use 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.

[0027] For particularly detachable mounting on the process vessel, the image acquisition unit is expediently equipped with a mounting interface, referred to as an image acquisition unit mounting interface for easier identification. The image acquisition unit mounting interface is functionally coordinated with the optional vessel mounting interface mentioned above.

[0028] The image recording unit is expediently equipped with an electromechanical connecting device, via which, during the process, an electrical connection is established with an electronic control device that specifies one or more variable operating parameters of the granulation process. The electromechanical connecting device expediently contains a plug-in connection device for at least one electrical cable or even directly at least one outgoing electrical cable.

[0029] In particular, an Internet connection to the electronic control device is established via the electromechanical connecting device, which enables data to be exchanged between the two components, and the voltage supply for providing the required operating voltage is also expediently carried out via this electromechanical connecting device.

[0030] The image recording unit used for the granulation process is preferably equipped with an optoelectrical assembly having an image sensor and a lens positioned in front of the image sensor for recording the image. The image sensor is expediently part of a sensor unit integrated into the optoelectrical assembly, which, in addition to the image sensor, also has further 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.

[0031] The lens is preferably a telecentric lens, which preferably has a fixed focal length. This has the advantage that the particle size is fixed when the image area is in focus and, unlike with wide-angle lenses, the difference between small particles close by and large particles far away can be clearly seen. Compared to a telecentric lens with a variable focal length, which can in principle also be used but where the focal plane has to be adjusted by making changes to the lens, a telecentric lens with a fixed focal length allows for much simpler adjustment and evaluation without 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 .

[0032] The telecentric lens, which preferably has a fixed focal length, results in a relatively shallow depth of field. For example, it is in the range of just 1.1 mm. Accordingly, in order to carry out the process, the focal plane defined by the optical components must be positioned precisely; this plane defines an image recording plane with optimum image sharpness. In order to achieve the greatest possible flexibility for the adjustment measures, it is advantageous if the image recording unit has an electrically actuated linear module carrying the opto-electrical assembly. The linear module enables continuous linear movement of the opto-electrical assembly to change and adjust the position of the focal plane, which is also referred to as the sharpness plane.It is advisable to maintain a fixed distance between the lens and the image sensor, which does not change 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 growing granulate particles are within the working area or focal plane of the lens.

[0033] 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.

[0034] To record clear images, it is advantageous to use an image recording unit with an illumination device that illuminates the area being imaged, generally at least the focal plane of the optoelectrical assembly. The illumination device is preferably designed using LED technology. When carrying out the method, the illumination device can be used either in pulsed operation matched to the frequency of the image recordings, or in continuous operation. The latter is technically easier to implement because the exposure time of the recorded image does not have to be matched to the bright phase of a flash light. Advantages can also be expected in terms of explosion protection because ignition sparks are avoided with continuous light.

[0035] 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 precise measurements. The illumination of the focal plane is very homogeneous.

[0036] The granulation process is particularly designed such that the two-dimensional inline images of the granulate taken in the process chamber during a granulation process 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 recording unit to the electronic control device.

[0037] 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 cable connection via a corresponding electrical communication line, but can also be done wirelessly, particularly via radio transmission.

[0038] The electronic control device expediently contains an electronic data processing device with which an image processing of the images taken by the image recording unit is carried out during the granulation process. In particular, the electronic data processing device calculates granule-related result values ​​on the basis of the image data obtained. 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. From the size distribution, a growth curve of the particle growth can be generated, from which the temporal course of the particle growth can be read off.Overall, the granulate-related result values ​​reflect the current actual state of the granulate particle quality in the ongoing granulation process.

[0039] The electronic data processing device expediently carries out image processing in such a way that the calculation of granulate-related result values ​​is based at least substantially only on the granulate particles lying in the focal plane of the image processing unit. In particular when using a telecentric lens, this ensures that the granulate particles taken into account are based on the same reading scale or measurement scale and that the calculated result values ​​therefore do not contain any relevant distortions. For easier differentiation, the granulate particles lying in the focal plane are referred to as reference granulate particles, with only the granulate particles identified as reference granulate particles being taken into account when calculating the granulate-related result values.The particle size is preferably taken into account, whereby the particle size, in particular the particle diameter, can be determined on the basis of an electronically measured particle circumference.

[0040] 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 granulate-related result values, sets the variable operating parameters influencing the operating state of the granulation process. For this purpose, the operating state setting device can output signals, referred to as operating signals, which correspond to the desired operating parameters, to the device components of the granulation device responsible for the respective operating parameters.Depending on the equipment, the operating signals are output, 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. When the method according to the invention is carried out, they are transmitted by the operating state setting device to, for example, one or more of these device components. The electronic operating state setting device can be a separate module of the electronic control device or an integral component of the electronic data processing device.

[0041] The electronic control device used is expediently designed so that it can carry out the above-mentioned control for generating the setting 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 images and previously stored setpoints, the setting signals for the electronic operating state setting device being generated as the comparison result. Expediently, the granulate-related result values ​​function in the control device as a controlled variable, 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.

[0042] 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 contains, for example, a keyboard and / or an interface for an electronic input device.

[0043] It is also 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, for example information regarding the temperature of a process gas or the flow rate of a sprayed-in granulation liquid. Particularly effective monitoring is possible if the output device contains 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, the average size distribution, and / or the morphology of the photographed granulate particles can be displayed and / or selected for display in continuous curves over the process time in freely definable subdivisions.

[0044] 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 able to interpret the 2D images recorded by the image acquisition unit and identify the aforementioned reference granule particles for use in calculating the granule-related result values. By training the AI, particle identification with a high degree of accuracy can be achieved.The training is carried out in particular 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.

[0045] 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 is manually defined, for example, as reference granulate 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 help the AI ​​make decisions and essentially carry out a control process, analyzing the available data—in particular the granulate-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 are used for the aforementioned output of results or other information, 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 which are designed, for example, as electrical interfaces through which the setting signals for the operating state setting device are output.The invention is explained in more detail below with reference to the accompanying drawing. It shows:

[0046] Figure 1 shows a preferred embodiment of a

[0047] Implementation of the granulation process according to the invention usable or used granulation device 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 dot-dash framed detail enlargement,

[0048] Figure 2 is an enlarged view of the section X framed by dash-dotted lines in Figure 1, wherein a preferred embodiment of the image recording unit is shown in a longitudinal section along section line II - II of Figure 4 in its position of use mounted on the outside of the process container,

[0049] Figure 3 shows the arrangement from Figure 2 in a top view with a view according to arrow III from Figure 2 with only a dash-dotted indication of a housing of the image recording unit enclosing the relevant components of the image recording unit,

[0050] Figure 4 is an axial front view of the image recording unit with a view according to arrow IV in Figure 2 and

[0051] Figure 5 is an illustration relating to the granulation process according to the invention, wherein a part of the image (b) shows a diagram reproduced by an output device, which is a histogram in which the number "A" of the granulate particles analyzed is plotted against the particle diameter "D", while a part of the image (a) shows an image of the granulate taken by the image recording unit, which forms the basis for generating the diagram according to part of the image (b).

[0052] Figure 1 shows a schematically illustrated granulation device 1, which is explained in more detail below and has a preferred design and can be used to carry out a granulation process. To carry out the granulation process, the granulation device 1 can be operated with a granulation method, which is also described in more detail below.

[0053] 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.

[0054] 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 position of use of the process container 3, the vertical axis 8 runs vertically.

[0055] The exemplary granulation apparatus 2 is a fluidization granulation apparatus which has the property of converting 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 formed in the process chamber 4. The fluidized bed state is maintained as long as the process gas is fed into the process chamber 4.

[0056] Within the fluidized bed 15, the individual granulate particles 12 of the granulate 11, which are present in different sizes, are strongly mixed up and behave like a fluid.

[0057] With the granulation device 1, a granulation process can be carried out by appropriate operation, with which a granulate 11 consisting of a plurality of granulate particles 12 can be produced. The material composition of the granulate particles 12 depends on the intended use, which is located, for example, in the fertilizer sector and, in particular, in the pharmaceutical field. The produced granulate 11 is used, for example, to produce fertilizer pellets or medicinally usable tablets.

[0058] A removal device 16, arranged particularly in the region of the container bottom 6 on the process container 3, which has a removal opening 16a suitable for opening as needed, allows removal of the produced granulate 11 for further use. For example, a tablet press can be connected to the removal device 16.

[0059] 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, in particular from below, according to the flow arrows 14. The process gas is, for example, an inert gas and 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.

[0060] 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 fan 18.

[0061] Also communicating with the process chamber 4, particularly in the region of the container top 7, is a process gas outlet 22, 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.

[0062] The granulation apparatus 2 is preferably a rotor granulator 2b, which applies to the illustrated embodiment. In this case, according to the illustrated embodiment, the granulation apparatus 2 has a rotor 23a with a rotor plate 23, which is arranged in the process chamber 4 and is rotatable by motor about a rotation axis 20 extending in the vertical direction 8a. To generate the rotary movement of the rotor 23a, an electrically actuated drive motor 24 is provided, which is fastened to the process container 3 outside the latter, in particular in the region of the container underside 6. The rotor plate 23 extends in a plane perpendicular to the vertical axis 8 and is therefore oriented horizontally, for example. It is located in a lower spatial region 4a of the process chamber 4 assigned to the container underside 6.

[0063] 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 off the process chamber 4. Between the outer edge of the rotor plate 23 of the rotor 23a and the side wall 25, an annular gap 26 is formed, illustrated enlarged in the drawing, through which the process gas fed in from below the rotor plate 23 via the process gas inlet 17 located there can flow upward.

[0064] 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 produce a fluidized bed 15.

[0065] 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.

[0066] In another advantageous embodiment of the rotor granulator 2b, the process gas which is passed through the process chamber 4 past the rotor plate 23 according to the flow arrows 14 is used as a barrier 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 brought about by the granulate particles 12 being moved through the process chamber 4 by the rotating rotor 23a in conjunction with blade-like structures 9 which are fixedly arranged on top of the rotor plate 23 and / or inside on the container wall 5 of the process container 3 and are indicated by dash-dotted lines in Figure 1, in particular in toroidal granulate flows with continuous mixing.In particular, when the granulate 11 rolls on 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.

[0067] The granulation device 1 is designed, by way of example, to carry out a granulation process which can be referred to as spray granulation. In this case, 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 placed 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 in from the liquid tank 27 and sprayed in a fine distribution into the process chamber 4, in particular with the addition of air to produce a fine spray mist.

[0068] The granulation device 1 can be used for spray granulation, in which the granules 11 are formed exclusively from the sprayed-in granulation liquid. A granulation liquid containing solids, for example a suspension, is sprayed into the process chamber 4, whereby the aqueous components evaporate and the remaining solids act as carrier cores, which are wetted with further supplied 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.

[0069] 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. In this case, the supplied granulation liquid is not used for core formation, but only for layered particle growth. By way of 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 design as a screw conveyor, and a carrier core storage device 35 connected to the conveyor unit 34 and filled with a sufficient quantity of carrier cores when the granulation process is carried out.

[0070] 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 moved by the process gas in a fluidized bed and sprayed with a granulation liquid acting as a binder liquid from the spray nozzle arrangement 28. In this case, a large number of particles are bonded to form agglomerates by forming liquid bridges, with the spraying process being continued until the agglomerates have reached the desired size for the granulate particles. The powdery particles can be introduced by means of the feed device 33.

[0071] 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 equipped with an electronic control device 36, indicated by dashed lines in Figure 1.

[0072] 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.

[0073] 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. 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 desired subcombination of these controllable device components 38 and / or further controllable device components 38.

[0074] On the part of the blower 18, a variable operating parameter can be the volume flow, and on the part of the heat source 21, the temperature of the process gas that can be fed in via the process gas inlet. On the part of the drive motor 24, a variable operating parameter can be the speed of the rotor 23a. On the part of the liquid pump 32, 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 part of the feed device 33, the variable operating parameters can be, for example, the quantity of carrier cores that can be fed into the process chamber 4.

[0075] 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 switching off 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.

[0076] It is understood that the granulation device 1 can alternatively be designed for carrying 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 by 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.

[0077] 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 photos 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 data transmission required for this purpose from the image recording unit 42 to the electronic control device 36.By way of 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.

[0078] 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.

[0079] The ability to capture images of the interior of the process chamber 4 offers the significant advantage of capturing images of the granules undergoing a granulation process in the 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 immediate intervention to modify the process flow as needed.

[0080] Preferably, an automated recording of images takes place continuously during the process, initiated by the electronic control device 36, wherein the electronic control device 36 initiates an immediate modification by influencing one or more operating parameters if the process does not conform to the standard. Removing granulate particles from the ongoing granulation process for carrying out analyses is not necessary with the described design and is also not carried out in the described method. 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 an objective 48 arranged in front 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 optoelectric assembly 45, which, in addition to the image sensor 47, also has further components of an electronic and / or mechanical nature.

[0081] The optical assembly 45 is mounted on a support structure 51 of the image recording unit 42, by means of which the image recording unit 42 is fastened to the granulation apparatus 2 in its illustrated position of use. 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 in such a way 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 position of use.

[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 which 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.In this case, 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 in the illustrated embodiment by the two cooperating fastening interfaces 53, 54, 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 recording unit 42 has on its front side 52 a light entry opening 58 which is aligned with the optical axis 46 and which is expediently covered by a translucent and in particular transparent front glass 61, which consists 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 screwed, for example, to the fastening flange 53a and which, in the position of use of the image recording unit 42, comes to lie between the fastening ring 54a and the fastening flange 53a. In this case, it expediently rests against the outer surface 55 or is only minimally spaced therefrom. The lens 48 is located between the light entry opening 58 and the sensor unit 49, being spaced from the light entry opening 58.

[0085] In the area of ​​the container fastening 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 unhindered 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 placed 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 regions of the container wall 5, is designed to be gas-tight.

[0086] The optoelectric assembly 45, in particular the lens 48, defines a focal plane 66, which can also be 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. The image recording unit 42 is preferably equipped with a positioning device 67, which allows a variable positioning of the focal plane 66 in order to position the focal plane 66 in the process space 4 such 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.

[0087] 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.

[0088] As a positioning device 67, an electrically actuated linear module 71 is provided by way of example, which has a stator 71a fastened to the support structure 51 and a slider 71b which can be moved linearly back and forth with respect to it while carrying out a positioning movement 70 indicated by a double arrow, wherein the optoelectrical assembly 45 is fastened to the slider 71b. The slider 71b is in particular designed like a slide. An electric drive motor 72 of the linear module 71, which interacts with the slider 71b in terms of drive, 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.

[0089] The lens 48 is preferably designed as a telecentric lens 48a. The telecentric lens 48a preferably has object-side telecentricity, with a bi-telecentric lens 48a with both object-side and image-side telecentricity being present as an example. The use of a telecentric lens 48a has the advantage that there is a constant image scale in the focal plane 66, with one pixel (px) consistently corresponding to a specific unit of length, which offers great advantages during image analysis due to simple conversion. The particle size is therefore defined when the image area is in focus. The shallow depth of field of, for example, 1 mm, which is inherent in the principle, can be easily compensated for by the positioning option via the positioning device 67, while maintaining a fixed focal length. Measures for calibration or recalibration to carry out the granulation process or .the granulation process is unnecessary.

[0090] 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 in the focal plane 66, sometimes at very high speed, are taken by means of the image recording unit 42 in a time sequence predetermined by the electronic control device 36, so that the occurrence of motion blur can be reduced to an insignificant level by short exposure times. Power is preferably supplied via PoE ("Power over Ethernet") because, in contrast to USB connections, significantly longer cable runs are possible here, which proves to be an advantage especially when integrated into larger granulation systems.

[0091] The image sensor 47 is, for example, a CCD sensor or a sensor based on CMOS technology. The pixel size is, for example, 4.5 / cm, which results in a good ratio between pixel size or sensor resolution on the one hand and light sensitivity on the other.

[0092] 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.

[0093] 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.

[0094] The optoelectrical assembly 45 is conveniently fastened to the positioning device 67 and, for example, to its slider 71b using a suitable fastening adapter 74.

[0095] 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 and thus shielded 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.

[0096] The image recording 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 placed in the region of the light entry opening 58 and there, in particular, directly behind the optional front glass 71.

[0097] The ring light 76a provides homogeneous illumination of the focal plane 66. The ring light 76a has a central aperture through which the recorded image information can pass.

[0098] It is advantageous if the central through-opening of the ring light 76a is larger than the lens diameter. In this way, the ring light 76a can be offset rearward by 20 mm to 50 mm for particularly homogeneous illumination. Sensor unit 49 and lens 48 can be displaced 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 recording unit 42 and lies within the process chamber 4 even with a high glass thickness of the viewing window 64a.

[0099] Preferably, the ring light 76a is at least partially accommodated in a heat sink 77 surrounding it, which ensures optimal heat dissipation. In this way, a ring light 76a with high light intensity can be used. It is generally advantageous if the illumination device 76 is implemented using LED technology, with the ring light 76a being an LED ring light, for example.

[0100] The electronic control device suitable for at least largely automated operation, hereinafter referred to as control device 36 for the sake of simplicity

[0101] 36 has a particularly advantageous structure in the illustrated embodiment, which is explained in more detail below.

[0102] 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 that follow one another immediately in time.

[0103] The data processing device 78 communicates with an electronic operating state setting device 81, which also belongs to the control device 36. This, in turn, is connected to the control device 36 via the signal lines already mentioned above.

[0104] 37 is connected to the controllable device components 38 of the granulation device 1. 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 fed to the operating state setting device 81 according to arrow 81a by the data processing device 78. The data processing device 78 also communicates with an electronic output device 82, which preferably has a display device 82a, which is in particular a display and is designed, for example, as a monitor.

[0105] 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 parameterization of the control device 36 and, for example, manual training of an artificial intelligence (AI) 84 (only symbolically indicated), with which the electronic control device 36 is preferably equipped.

[0106] The input device 83 can be designed for remote input by means of digital instruments and / or for manual keyboard input.

[0107] 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.

[0108] 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 initiated by the data processing device 78, which is indicated in Figure 1 by an arrow at 86. The image is recorded inline, i.e. while the 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 recorded in the focal plane 66, for example in the outer boundary layer of the fluidized granules 11. Each image is a snapshot of the granulate particles 12 moving past the light inlet opening 58 at high speed.

[0109] In the image section (a) of Figure 5, an image 42a taken by the image recording unit 42 is schematically illustrated, 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.

[0110] 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, in which an electronic image analysis is carried out. As part of this image analysis, the data processing device 78 calculates granule-related result values ​​of 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 diameter.

[0111] However, in this evaluation, where possible, only those granulate particles 12 are taken into account which lie in the focal plane 66 in the respective image recording 42a. Such granulate particles 12 are referred to as reference granulate particles 12a for easier differentiation and are additionally identified by a dashed contour line in the image recording 42a in Figure 5 (a). For the reference granulate particles 12a lying in the focal plane 66, the image scale is known due to the optical design of the opto-electrical assembly 45 explained above, so that the granulate dimensions can be very easily calculated based on the pixel size in accordance with the actual conditions.

[0112] 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.

[0113] By 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 that it can recognize the reference granulate particles 12a as accurately as possible. This training is carried out in particular by manually labeling images taken during a granulation process or images of a granulate 11 input via a suitably designed input device 83 as reference granulate particles 12a using a labeling medium, for example a computer mouse. As the training period increases, the AI ​​84 can reliably recognize the reference granulate particles 12a during real operation of a granulation process.

[0114] The data processing device 78 is able, in particular by using the AI ​​84, to calculate the granule-related result values ​​already mentioned above from the identified reference granulate particles 12a. For example, the identified reference granulate particles 12a can be measured electronically with regard to their particle size and in particular with regard to their circumference. For example, the software creates a closed outline around the identified reference granulate particles 12a - marked with dashed contour lines in Figure 5 (a) - and calculates the particle circumference from this, taking into account the underlying image scale - for example, an effective pixel size of 6.12 / zm per pixel. A particle diameter representing a particle size can then be calculated from this value.

[0115] Every granulation process is based on the aim 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 aim 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).

[0116] 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 granulate-related result values.

[0117] 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 granulate-related result values ​​calculated by the data processing device 78 and the previously stored target values. Depending on the comparison result, the aforementioned electrical setting signals are generated and fed as input signals to the electronic operating state setting device 81 as indicated by arrow 81a. Thus, within the control loop, the granulate-related result values ​​function as the controlled variable, the target values ​​as the reference variable, and the setting 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 on the basis of the setting signals received and can 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.

[0118] The output device 82 is, by way of example, capable of displaying at least granule-related result values ​​corresponding to the preceding calculation by the data processing device 78, which expediently also occurs during the granulation process. Figure 5(b) shows, by way of example, the visualization of a histogram performed by the output device 82, which represents the size distribution of the granule particles—here: the number "A" of granule particles over the particle diameter "D"—based on an image recording 42a shown in Figure 5(a). Also displayed is an average value "M" of all particle diameters "D" on which the image evaluation is based. The display can be made separately for each image recording by the image recording unit 42 or, in turn, as an average value from the average values ​​of several consecutively recorded images.For example, images can be evaluated at regular intervals and combined and visualized to form a growth curve throughout the process.

[0119] 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.

[0120] 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.

[0121] 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.

[0122] The convolutional network contains a feature extractor and a classifier. The feature extractor can generate an RPN (Region Proposal Network) that divides the captured image into regions and assigns a probability value to these regions. Regions of Interest (ROIs) are generated using this method – regions can be merged for this purpose – and an assessment is made of the probability of object detection for 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 granulate particle. This training data is created manually, and input device 83 can be used.The neural network used can, for example, 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.

[0123] 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 achieved, the granulation process is expediently aborted or interrupted. The verification required for this can be carried out software-based using the data processing device 78 or, alternatively or additionally, by monitoring by an operator while observing the display device 82a.

Claims

Claims 1. Granulation method 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 in 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 method according to claim 1, characterized in that 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 method according to claim 1 or 2, characterized in that by means of the electronic control device (36) an image processing of the images taken 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 determined, wherein setting signals are generated on the basis of the granulate-specific result values, by means of which the variable operating parameters influencing the operating state of the granulation process are specified.

4. Granulation process according to claim 3, characterized in that the setting signals are generated by means of a control based on a comparison between the granulate-related result values ​​and predetermined target values.

5. Granulation method according to claim 3 or 4, characterized in that image processing is carried out such that, for the calculation of the granulate-related result values, those granulate particles (12) are identified as reference granulate particles (12a) from the granulate particles (12) visible in the recorded images, 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 in that 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 records the images of the Process chamber (4) and thus can produce inline images of the granulate (11) undergoing a granulation process in the process chamber (4).

7. Granulation process according to claim 6, characterized in 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 in that it is carried out by means of a granulation device (1) is carried out, the granulation apparatus (2) of which 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 in that it is carried out by means of a granulation device (1) whose granulation apparatus (2) 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 chamber (4).

10. Granulation process according to claim 9, characterized in 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 in 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 predetermined in particular by switching the granulation process on and off.

12. Granulation process according to one of claims 1 to 11, characterized in that it is carried out by means of a granulation apparatus (2) which has on the process container (3) a process gas inlet (17) communicating with the process chamber (4) and used for feeding in a process gas, and a process gas outlet (22) likewise communicating with the process chamber (4) and used for discharging the fed-in process gas.

13. Granulation process according to claim 12, characterized in 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 in 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 in that a variable operating parameter of the granulation process is the volume flow and / or the spraying time and / or the droplet size of the granulation liquid.

16. Granulation process according to one of claims 1 to 15, characterized in that it is carried out by means of a granulation apparatus (2) which has a feeding device (33) which is used during the process implementation for feeding carrier cores, in particular in powder form, which form the basis of the granulate structure into the process space (4).

17. Granulation process according to claim 16, characterized in 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 in 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 taken with the image recording unit (42) through the transparent wall section (64).

19. Granulation process according to claim 18, characterized in that 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 in that the image recording unit (42) is fastened externally to the process container (3) at least during the process execution, wherein expediently externally to the A container fastening interface (54) adapted to the image recording unit (42) is arranged on the container wall (5) of the process container (3).

21. Granulation method according to one of claims 1 to 20, characterized in that 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 method according to one of claims 1 to 21, characterized in 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 method according to claim 22, characterized in that 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 method according to claim 22 or 23, characterized in that the image recording unit (42) used is equipped with a positioning device (67) which enables a variable positioning of the opto-electrical assembly (45) causing a change in the position of a focal plane (66) of the lens (48) and the expediently has an electrically actuated linear module (71) carrying the optoelectric assembly (45).

25. Granulation process according to one of claims 1 to 24, characterized in that 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 method according to one of claims 1 to 25, characterized in 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 method according to one of claims 1 to 26, characterized in that the electronic control device (36) used contains an electronic data processing device (78) with which an image processing of the images taken 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 method according to claim 27, characterized in that by means of the electronic data processing device (78) an image processing is carried out in such a way that 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 method according to claim 27 or 28, characterized in that an electronic control device (36) is used which contains an electronic operating state setting device (81) by 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 method according to claim 29, characterized in that 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 method according to one of claims 1 to 30, characterized in that 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 method according to one of claims 1 to 31, characterized in that an electronic control device (36) is used which is equipped with an artificial intelligence (84), which is realized in particular using a convolutional neural network.

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