Device and method for processing a suspension of fibre-comprising material to yield a container

Abstract

The invention relates to a device for processing a suspension of fibre-comprising material to yield a container, comprising a mixing device for mixing the suspension of fibre-comprising material, a moulding device for moulding the suspension of fibre-comprising material into a container and a control unit, wherein the device comprises at least one sensor for determining a turbidity value of the suspension of fibre-comprising material and the control unit is designed to determine a processing state of the suspension of fibre-comprising material in the mixing device, based on the turbidity value.

Description

[0001] Apparatus and method for processing a suspension of fiber-comprising material into a container

[0002] The present invention relates to a device for processing a suspension of fiber-comprising material into a container according to independent claim 1 and a corresponding method according to the independent method claim.

[0003] State of the art

[0004] Devices for producing containers from material comprising fibers are known from the prior art.

[0005] To produce the containers, a perforated container mold is typically pressurized with a suspension of fiber-containing material. The overpressure generated in the container mold causes the fiber-containing material to settle on the perforated wall of the mold, while the liquid phase of the suspension is forced out of the container mold through the perforation. By applying heat or electromagnetic radiation to the fiber-containing material deposited on the container mold, it can be cured into a container.

[0006] To produce containers of sufficiently high quality, the quality of the provided suspension of fiber-containing material plays a crucial role. Typically, the suspension of fiber-containing material is mixed in a mixing device for a specific time interval to evenly disperse the solid and liquid components and reduce the particle size of the fiber-containing material.

[0007] However, this procedure has the disadvantage that it cannot be precisely determined whether the suspension of fiber-containing material has been sufficiently dispersed and whether the particles contained therein have the desired particle diameter. Furthermore, the solid or liquid content of the suspension is typically not monitored. This, in turn, means that the quality of the suspension of fiber-containing material produced with the mixing device cannot be clearly determined, and the production of containers of consistently high quality cannot be guaranteed.

[0008] Based on the known state of the art, the technical problem to be solved is to provide a device and a method with which the quality of containers made of fiber-containing material can be improved.

[0009] Solution

[0010] This object is achieved by the device for processing a suspension of fiber-comprising material into a container according to independent claim 1 and the corresponding method for processing a suspension of fiber-comprising material into a container according to the independent method claim. Preferred developments are covered in the dependent claims.

[0011] The device according to the invention for processing a suspension of material comprising fibers into a container comprises a mixing device for mixing the suspension of material comprising fibers, a shaping device for shaping the suspension of material comprising fibers into a container and a control unit, wherein the device comprises at least one sensor for determining a turbidity value of the suspension of material comprising fibers and / or a partial amount of the suspension remaining after shaping in the shaping device and the control unit is designed to determine a processing state of the suspension of material comprising fibers in the mixing device and / or a quality of the container produced based on the turbidity value.

[0012] The container is preferably a bottle, can, or the like used in the beverage industry. However, this type of container design is not to be understood as limiting, so that the suspension of fiber-comprising material can also be processed into any other type of container using the device. For example, the container can also be a can, tube, or cup used in the beverage, pharmaceutical, healthcare, or food industries, or any other container suitable for holding any liquid or pasty medium.

[0013] Fiber-comprising material can, for example, mean renewable and / or recycled natural materials based on plants, such as cellulose-containing or cellulosic materials. In particular, these can be natural fibers, such as plant fibers, paper fibers, or wood fibers. The fibers can also be or comprise flakes. The fiber-comprising material can also comprise non-sustainable components, such as synthetic or metallic fibers. The fiber-comprising material is preferably pulp or papier-mâché. However, it can also be any other fiber-comprising material that is suitable for producing a container. The suspension of fiber-comprising material can comprise water and a binder in addition to the fibers. However, the suspension can also comprise other components, such as additives.The additive may, for example, be provided to create a liquid and / or gas barrier on the surface of the container made from the suspension of material comprising fibers.

[0014] The mixing device can be designed as a stirring device with a stirring tool for mixing the suspension of fiber-comprising material. The mixing device can, in particular, be designed to disperse the fiber-comprising material with the liquid phase, in particular comprising water, of the suspension.

[0015] Due to the shear force acting on the suspension during the mixing process, the mixing device can also reduce the particle size of solids contained in the suspension, such as the material comprising fibers and / or the additive, during the mixing process.

[0016] The device may further comprise at least a first container in which the fiber-comprising material is kept ready. A suspension of the fiber-comprising material and a liquid may already be mixed in the first container, which suspension has a higher fiber content than the finished suspension in the mixing device.

[0017] The device may further comprise at least a second container in which a liquid is kept.

[0018] A line can be arranged between the first and second containers and the mixing device, through which the fiber-comprising material and the liquid can be introduced into the mixing device. A valve controllable by the control unit can be arranged along each of the lines. A pump controllable by the control unit can be arranged along each of the lines or in the respective container.

[0019] The molding device can be a mold made of metal and / or plastic. For molding the suspension of fiber-comprising material into a container, the mold can comprise a cavity. This cavity can represent a negative impression of the container to be produced and can be perforated so that the liquid phase of the suspension can be discharged from the molding device through the perforation and a deposition of the fiber-comprising material on a wall of the cavity can be achieved. Optionally, the molding device can comprise a curing device by means of which the fiber-comprising material can be cured to form a container. However, the molding device can also be designed as any other type of device suitable for producing a container from fiber-comprising material.In one embodiment, the molding apparatus may comprise two molds - a first mold for producing a preform of the container and a second mold for producing the final container.

[0020] The sensor for determining the turbidity value can be a sensor that determines the turbidity value using an optical method. For example, the sensor can be designed to measure scattered light and / or absorption. However, it can also be any other type of sensor designed to determine a turbidity value. The turbidity value can be determined by the sensor with respect to a standard turbidity liquid, formazin. However, the turbidity value can also be determined with respect to any other reference liquid.

[0021] The processing state can, for example, be a solid portion of the suspension of fiber-comprising material. The solid portion can, for example, be a portion of solid of a certain particle size or a portion of solid of a certain particle size range. Solid can, for example, mean the fiber-comprising material or an additive. However, it can also be any other solid contained in the suspension of fiber-comprising material. Alternatively, the processing state can also mean a liquid portion of the suspension of fiber-comprising material. The liquid portion can, for example, be a water portion.

[0022] The quality of the manufactured container may, in particular, be a physical property of the container, such as a wall thickness, a wall thickness distribution, and / or a weight of the manufactured container. However, it may also be any other quality of the manufactured container not explicitly mentioned here.

[0023] The quality of the suspension of fiber-containing material can be assessed based on the processing state of the suspension of fiber-containing material, determined by the turbidity value. Since the processing state or the quality of the suspension of fiber-containing material, in turn, has a direct influence on the quality of the containers produced using the suspension in the molding device, the quality of the containers produced from fiber-containing material can be improved by the device according to the invention.

[0024] In one embodiment, the sensor can be arranged downstream of the mixing device and / or in the mixing device. This type of arrangement allows the turbidity value to be determined flexibly at different positions in the device. The arrangement of the sensor in the mixing device allows continuous determination of the processing state of the suspension of fiber-comprising material during the mixing process, while an arrangement of the sensor downstream of the mixing device can be used, for example, for quality control of the suspension provided by the mixing device. In one embodiment, the mixing device can be designed to feed the suspension of fiber-comprising material to the molding device based on the processing state of the suspension of fiber-comprising material.Since the processing state of the suspension is directly related to the quality of the containers produced from the suspension of fiber-containing material, this parameter is particularly suitable for assessing whether the suspension can be made available to the molding device.

[0025] If the sensor is arranged in the mixing device, the composition of the suspension with regard to its proportions of the material comprising fibers and the liquid can be influenced directly during mixing.

[0026] In one embodiment, if the turbidity value deviates from a target value by more than a predetermined first threshold value, the mixing device can be configured to further mix the suspension of fiber-comprising material in the mixing device and not feed it to the molding device. This prevents an unfinished suspension that does not meet the desired quality from being fed to the molding device. This can prevent the production of low-quality containers.

[0027] In a further development of this embodiment, the mixing device can be configured to change a solids content and / or a liquid content of the suspension of fiber-comprising material in the mixing device if a first time interval is exceeded or if a change in the turbidity value within a second time interval is below a predetermined second threshold value. This prevents unwanted downtimes of the molding device caused by an excessively low or excessive solids or liquid content in the suspension of fiber-comprising material.

[0028] In one embodiment, the mixing device can be configured to feed the suspension of fiber-comprising material to the molding device if the turbidity value of the suspension of fiber-comprising material deviates from a target value by less than a predetermined first threshold value. This ensures that the suspension is only fed to the molding device when it has the desired processing state or a sufficiently high quality. This ensures the production of containers with consistently high quality.

[0029] In one embodiment, the molding device can be connected to the mixing device via a return line, wherein the portion of the supplied suspension of fiber-comprising material remaining in the molding device after molding the container can be returned from the molding device to the mixing device via the return line, with the sensor being arranged in the return line. Thus, a portion of the suspension of fiber-comprising material remaining during the molding of the container can be recycled and fed back into the mixing device.

[0030] By arranging the sensor in the return line, the turbidity value of the returned portion of the suspension can be used to determine, for example, a solid or water content in the returned portion and to take this into account during the mixing process of the suspension from material containing fibers in the mixing device.

[0031] In another embodiment, the molding device may have an outlet through which the residues of the suspension are drained off after molding, for example to a drain.

[0032] The sensor can be located in this outlet.

[0033] In this case, and if the sensor is located in the return line, it can be concluded that the mold is blocked if, for example, the turbidity value falls below a certain threshold. In this case, an error message can be issued via the control unit or, for example, automatic mold cleaning can be initiated. If all solids or fibers are removed from the liquid by the mold, only residual liquid remains, which can then be analyzed by a sensor located downstream of the molding device.

[0034] Furthermore, it is planned to arrange a turbidity sensor downstream and upstream of the forming device.

[0035] Furthermore, it is planned to transfer the measurement data and, if necessary, other data on container quality to a central database. The central database can make the obtained data available to other devices at other locations.

[0036] The mixing device preferably works in batches.

[0037] Furthermore, the device can have two mixing devices, one of which produces a suspension, while the other dispenses a ready-made suspension.

[0038] In one embodiment, the device may comprise a buffer tank between the mixing device and the forming device, in which ready-mixed suspensions can be temporarily stored.

[0039] A pump for transporting the suspension can be arranged between the mixing device and the molding device. This pump is preferably controllable via the control device. Alternatively or additionally, the suspension can be transported by gravity by arranging the mixing device above the molding device.

[0040] The turbidity sensor can be arranged in a secondary pipe arranged parallel to a main pipe.

[0041] The turbidity sensor may comprise a light source, e.g. an LED, and a detector.

[0042] The turbidity sensor can be arranged in or on the wall of a mixing vessel of the mixing device or in or on a pipe through which the suspension is transported.

[0043] The turbidity sensor can extend at least partially into the suspension. Alternatively, sight glasses can be provided on pipe walls / mixing device walls, through which a measurement can be taken using the turbidity sensor. The turbidity sensor can operate, for example, analogously to the method disclosed in document DE102014118205A1.

[0044] According to the invention, a method is also provided for processing a suspension of fiber-comprising material into a container, in which the suspension of fiber-comprising material is mixed in a mixing device and formed into a container in a forming device, wherein at least one sensor is provided for determining a turbidity value of the suspension of fiber-comprising material and / or a partial amount of the suspension remaining after forming in the forming device, wherein a processing state of the suspension of fiber-comprising material in the mixing device and / or a quality of the container produced is determined by a control unit based on the turbidity value.

[0045] By determining the processing state of the suspension of fiber-containing material, the quality of the suspension of fiber-containing material can be precisely determined. Since the quality of the suspension, in turn, directly affects the quality of the containers produced from the suspension, the quality of the containers produced from fiber-containing material can be improved by the method according to the invention.

[0046] In one embodiment, the sensor can be arranged downstream of the mixing device and / or within the mixing device. This type of arrangement allows the turbidity value to be determined flexibly at various positions within the device. The arrangement of the sensor within the mixing device allows monitoring of the processing status of the suspension of fiber-comprising material during the mixing process, while a sensor arrangement downstream of the mixing device can be used, for example, for quality control of the suspension provided by the mixing device.

[0047] In one embodiment, the suspension of fiber-comprising material can be fed to the molding device based on the processing state of the suspension of fiber-comprising material. This ensures that the suspension has reached a desired processing state or quality before it is provided to the molding device, ensuring a consistently high quality of the containers produced from the suspension.

[0048] In one embodiment, if the turbidity value deviates from a target value by more than a predetermined first threshold value, the suspension of fiber-comprising material can be further mixed in the mixing device and not fed to the molding device. This ensures that the suspension has reached a certain processing state and thus a certain quality before it is provided to the molding device. This, in turn, ensures the quality of the containers produced from the suspension.

[0049] In a further development of this embodiment, if a first time interval is exceeded or if a change in the turbidity value within a second time interval is below a predetermined second threshold value, a solids content and / or a liquid content of the suspension of fiber-comprising material in the mixing device can be changed. This prevents unwanted downtimes of the device, during which the suspension of fiber-comprising material is not fed to the molding device due to an excessively low or excessive solids or liquid content.

[0050] In one embodiment, if the turbidity value of the suspension of fiber-comprising material deviates from a target value by less than a predetermined first threshold value, the suspension of fiber-comprising material can be fed to the molding device. This ensures that the suspension is only fed to the molding device when it has the desired processing state or a sufficiently high quality. In this way, containers of consistently high quality can be produced using the molding device.

[0051] In one embodiment, the molding device can be connected to the mixing device via a return line, wherein the portion of the supplied suspension of fiber-comprising material remaining in the molding device after molding of the container can be returned from the molding device to the mixing device via the return line, wherein the sensor is arranged in the return line. Thus, a portion of the suspension of fiber-comprising material remaining during molding of the container can be recycled and fed back to the mixing device. By arranging the sensor in the return line, the turbidity value of the returned portion of the suspension can be used to determine, for example, a solid or water content of the returned portion and to take this into account during the mixing process of the suspension in the mixing device.Alternatively, a turbidity measurement can be carried out in a drain, as described above.

[0052] In one embodiment, the turbidity value can be used to determine the proportion of an additive in the suspension of fiber-containing material. Thus, the proportion of specific solids in the suspension of fiber-containing material can also be determined, further improving the quality of the containers produced from the suspension.

[0053] After a turbidity measurement, the control device can determine whether there are too few or too many fibers in the suspension.

[0054] Once determined, the ratio can be readjusted by automatically adding fiber or liquid. The ratio can be changed, for example, by opening one of the aforementioned valves or by switching on one of the aforementioned pumps.

[0055] Short description of the characters

[0056] Fig. 1 Schematic representation of an apparatus for processing a suspension of material comprising fibers into a container according to an embodiment.

[0057] Detailed description of the characters

[0058] Figure 1 shows a device 100 for processing a suspension of fiber-comprising material 111 into a container.

[0059] According to the invention, the device 100 comprises a mixing device 101 for mixing the suspension of fiber-comprising material 111, a shaping device 104 for shaping the suspension of fiber-comprising material 111 into a container, at least one sensor 102, 106 for determining a turbidity value of the suspension of fiber-comprising material 111 and / or a partial amount of the suspension remaining in the shaping device after shaping, and a control unit 112, wherein the control unit 112 is designed according to the invention to determine a processing state of the suspension of fiber-comprising material 111 and / or a quality of the container produced based on the turbidity value.

[0060] The mixing device 101 can be connected to the molding device 104 via a supply line 103, so that the suspension of fiber-comprising material 111 can be fed to the molding device 104 via the supply line 103. Optionally, the mixing device 101 can comprise a first valve 108 at an outlet connected to the supply line 103, by means of which the suspension 111 can be fed to the supply line 103 or to the molding device 104 in a controlled manner, and the feed can also be stopped if necessary. The molding device 104 can in turn be connected to the mixing device 101 via a return line 105, so that a portion of the suspension of fiber-comprising material 111 remaining in the molding device 104 during the molding of the container can be recycled and fed back to the mixing device 101.

[0061] Optionally, the molding device 104 can also be connected to a discharge line 109 in order to feed the partial amount of the suspension of fiber-comprising material 111 remaining during molding of the container, for example, to a tank or a discharge device. A second valve 110 can be provided at an outlet of the molding device 104, by means of which the remaining partial amount of the suspension 111 can be fed to the return line 105 and / or the discharge line 109. In one embodiment, it can also be provided, for example, that the second valve 110 is designed to feed only a portion of the partial amount of the suspension 111 remaining during molding to the mixing device 101 via the return line 105 and to discharge another portion of the partial amount of the suspension 111 via the discharge line 109 into the reservoir or the discharge device.

[0062] In the embodiment discussed in connection with Figure 1, two sensors 102, 106 are provided for determining the turbidity value, with one sensor 102 being arranged in the mixing device 101 and one sensor 106 in the return line 105. The number of two sensors 102, 106 selected here and their type of arrangement in the device 100 are to be understood as examples. For example, any number of sensors greater than or equal to one can be provided. Furthermore, the at least one sensor 102, 106 can also be arranged at any other position in the device 100. In an alternative embodiment, it can also be provided, for example, that only one sensor is provided and that this is arranged in the mixing device 101 or in the return line 105 or in the supply line 103, for example downstream of the valve 108.Alternatively, for example, three sensors can be provided, with one sensor being arranged in the mixing device 101, one sensor in the supply line 103 and one sensor in the return line 105.

[0063] The mixing device 101 can be designed as a stirring device with a stirring tool, wherein the stirring tool can be designed, for example, as an anchor stirrer, pitched-blade stirrer, propeller stirrer, helical stirrer, and / or disc stirrer. The mixing device 101 can be designed for axial, radial, and / or tangential conveyance of the suspension of fiber-comprising material 111 in order to achieve particularly uniform dispersion of the solid and liquid components of the suspension. Furthermore, the shear force acting on the suspension 111 during mixing can continuously reduce the average particle size of the solid content contained in the suspension 111, such as the fiber-comprising material and / or the additive, during mixing.

[0064] Optionally, the liquid and solid phases of the suspension of fiber-comprising material can be supplied to the mixing device 101 via at least one supply line. For example, a first supply line can be provided via which the liquid phase, for example water, is supplied to the mixing device 101, and a second supply line via which the solid phase is supplied to the mixing device 101. Further supply lines can also be provided in order to separately supply the various components of the solid phase, such as the fiber-comprising material and the additive, to the mixing device 101. Due to the possibility of the mixing device 101 separately supplying the various components of the suspension of fiber-comprising material 111, for example, a proportion of the fiber-comprising material and / or a proportion of the additive and / or a proportion of the liquid phase of the suspension 111 can be flexibly adjusted.

[0065] The molding device 104 can be configured as a mold. The mold can comprise a cavity, which can represent a negative impression of the container to be produced. The cavity can be perforated so that when the cavity is loaded with the suspension of fiber-comprising material 111, the liquid phase of the suspension of fiber-comprising material can be discharged from the mold via the perforation, and deposition of the solid portion of the suspension or of the fiber-comprising material on a wall of the cavity can be achieved.

[0066] The molding device can comprise a curing device for curing the fiber-comprising material deposited on the mold wall to form a container. For this purpose, the curing device can be configured, for example, to subject the fiber-comprising material to thermal radiation and / or electromagnetic radiation, such as microwave or infrared radiation. The molding device can also be assigned a magazine for molds with differently configured cavities, so that the mold of the molding device can be flexibly exchanged and containers of various types can be produced.

[0067] The container is preferably a bottle used in the beverage industry. However, this type of design is not to be understood as limiting, so that the suspension of fiber-comprising material can also be processed into any other type of container using the device. For example, the container can also be a can, tube, or cup used in the beverage, pharmaceutical, healthcare, or food industries. However, it can also be any other type of container suitable for holding a liquid or pasty medium.

[0068] Fiber-comprising material can, for example, mean renewable and / or recycled natural materials based on plants, such as cellulose-containing or cellulosic materials. In particular, these can be natural fibers, such as plant fibers, paper fibers, or wood fibers. The fibers can also be or comprise flakes. The fiber-comprising material can also comprise non-sustainable components, such as synthetic or metallic fibers. The fiber-comprising material is preferably pulp or papier-mâché. However, it can also be any other fiber-comprising material that is suitable for producing a container. The suspension of fiber-comprising material can comprise water and a binder in addition to the fibers. However, the suspension can also comprise other components, such as additives.

[0069] The sensor 102, 106 for determining the turbidity value can be an optical sensor. The sensor can, for example, be configured to perform a scattered light measurement and / or an absorption measurement. For this purpose, the sensor can, for example, comprise a light source, which can operate in the infrared or visible wavelength range, and a detector for detecting the electromagnetic radiation emitted by the light source.

[0070] In a sensor 102, 106 configured for absorption measurement, the light source and the detector can be arranged parallel to each other. Thus, an attenuation of the intensity of the electromagnetic radiation emitted by the light source caused by the suspension of material comprising fibers can be determined parallel to the emission direction. With increasing particle concentration or turbidity, the absorption caused by the suspension or the attenuation of the intensity of the electromagnetic radiation emitted by the light source increases, so that absorption measurement represents a sensitive method for determining turbidity.

[0071] In a sensor 102, 106 configured for scattered light measurement, the light source and detector can be arranged in a single unit, so that the intensity of the electromagnetic radiation backscattered by 180° by the suspension of fiber-comprising material 111 can be detected by the detector, wherein the intensity of the electromagnetic radiation backscattered by 180° increases with increasing particle concentration or turbidity. Alternatively, the sensor 102, 106 for scattered light measurement can also be configured such that the light source and the detector are arranged to determine the intensity of the electromagnetic radiation side-scattered by the suspension of fiber-comprising material 111 at an angle of 0° < α < 180° with respect to an incident irradiation direction. In one embodiment, the angle α can assume a value of 90°.Since the intensity of the side-scattered electromagnetic radiation at a certain angle 0° < a < 180° also depends on the particle size, angle-dependent turbidity measurements can be used to obtain additional information about the particle size of the solid fraction in the suspension or to determine particle size distributions.

[0072] In one embodiment, it can be provided that the sensor 102, 106 is designed to determine the turbidity value based on a light reflection measurement or an absorption measurement. In an alternative embodiment, it can also be provided that the sensor 102, 106 is designed to measure light reflection and absorption. For this purpose, the sensor 102, 106 can, for example, comprise at least two sensor components. Thus, in one embodiment, it can be provided, for example, that the sensor comprises a first sensor component for measuring absorption and / or a second sensor component for measuring scattered light, which is designed to determine the intensity of the electromagnetic radiation backscattered by the suspension through 180° and / or a third sensor component, which is designed to determine the intensity of the electromagnetic radiation side-scattered by the suspension through an angle 0° < a < 180°.All three sensor components can be provided or only two of the three sensor components described can be present in any combination.

[0073] A turbidity value to be determined for the suspension can, for example, be determined from an average of the turbidity values ​​determined with the individual sensor components.

[0074] By designing the sensor 102, 106 to be able to carry out various turbidity measurement methods, turbidity values ​​can be measured over a wide parameter range and information about the particle size can also be obtained. Turbidity measurement based on side scattering is particularly suitable for determining weak turbidity values, while absorption measurement, in turn, is particularly suitable for determining medium to strong turbidity. The backscattering measurement method is preferably used for determining particularly strong turbidity. As described above, when the suspension of fiber-comprising material 111 is mixed, the solid content and the liquid content in the suspension 111 are dispersed, whereby the shear force exerted on the suspension during mixing leads to a reduction in the average particle size of the solid content contained in the suspension.Due to the change in the average particle size, the turbidity of the suspension of fiber-comprising material 111 also changes during mixing of the suspension in the mixing device. If the suspension is sufficiently dispersed, which can be determined, for example, by the fact that the particle sizes of the solid fraction no longer change significantly during mixing (for example, do not fluctuate by more than an amount B over a specified time interval Δt, such as 20 s, 30 s, or 1 min), then the turbidity value of the suspension of fiber-comprising material 111 will also converge towards a constant value. Thus, by measuring the turbidity value, it can be determined whether the solid fraction and the liquid fraction of the suspension have reached a desired degree of dispersion or whether the solid fraction of the suspension 111 has reached a desired particle size distribution and can be fed to the molding device.

[0075] Consequently, the measurement of the turbidity value can be used to determine a processing state of the suspension of fiber-comprising material 111 and / or a portion of the suspension of fiber-comprising material remaining after molding in the molding device. Furthermore, a quality of the manufactured container can be determined based on the turbidity value.

[0076] According to the invention, the determination of the processing state of the suspension of fiber-comprising material 111 and / or the nature of the container produced is carried out by means of the control unit 112 based on the turbidity value determined by the at least one sensor 102, 106.

[0077] The processing state can be a solid portion of the suspension of fiber-comprising material 111. The solid portion can, for example, also be a portion of solid of a certain particle size or a portion of solid of a certain particle size range. Solid can, for example, mean the fiber-comprising material or an additive. However, it can also be any other solid contained in the suspension of fiber-comprising material. Alternatively, the processing state can also be a liquid portion of the suspension of fiber-comprising material 111. The liquid portion can, for example, be a water portion.The quality of the manufactured container may, in particular, be a physical property of the manufactured container, such as a wall thickness, a wall thickness distribution, and / or a weight of the manufactured container. However, it may also be any other quality of the manufactured container not explicitly mentioned here.

[0078] The control unit 112 can, for example, be configured as a computer or server unit and comprise a storage unit. A database can be stored in the storage unit, wherein various turbidity values ​​are assigned to a corresponding processing state of the suspension of fiber-comprising material and / or a specific quality of the manufactured container. This assignment can be stored in the database for each of the various sensors. Consequently, based on the data stored in the database, the control unit can determine the processing state of the suspension of fiber-comprising material and / or the quality of the manufactured container based on the turbidity value. The processing state of the suspension 111 also represents a measured variable that can provide direct information about the composition of the suspension 111 and its quality.In particular, by determining the turbidity value, it can be assessed whether the suspension 111 has a desired processing state and thus a required quality. The quality of the suspension can, in turn, be linked to the quality of the container made of fiber-containing material produced from the suspension, so that by taking the processing state into account, the quality of the containers produced from fiber-containing material can be improved.

[0079] In one embodiment, it may be provided that the control unit 112 can determine a wall thickness, a wall thickness distribution and / or a weight of the container produced by comparing the turbidity value of the suspension of material comprising fibers before molding and the turbidity value of a portion of the suspension remaining in the molding device after molding.

[0080] In one embodiment, it can be provided that the control unit 112 comprises artificial intelligence and the turbidity value of the suspension of fiber-comprising material 111 is fed to the artificial intelligence as a parameter, and the artificial intelligence is designed to determine a quality of the suspension and / or a quality of the containers produced using the suspension 111 based on the turbidity value. The artificial intelligence can be trained using turbidity value data measured on various suspensions of fiber-comprising material with different compositions, wherein the various suspensions can, for example, have different solids fractions or different particle size distributions of the solids fractions, and quality data describing the quality of the containers produced using the various suspensions.In one embodiment, the artificial intelligence may be implemented as a neural network.

[0081] Alternatively, a deterministically operating algorithm can also be implemented in the control unit 112, to which the turbidity value of the suspension of fiber-comprising material 111 is supplied as a parameter and which, based on the turbidity value, can determine a processing state of the suspension and / or a condition of the container produced or a quality of the suspension 111 and / or a quality of the containers produced from the suspension 111.

[0082] The control unit 112 can be connected to the various controllable components of the device 100 for processing the suspension of fiber-comprising material 111 either via a cable connection 113 or via a wireless connection 113. A controllable component can be understood to mean, for example, the mixing device 101, the shaping device 104, the at least one sensor 102, 106, and also any other controllable component of the device 100 for processing the suspension of fiber-comprising material. The control unit 112 can be designed to control an operating parameter of the controllable component and / or to read it out. For example, the control unit 112 can be designed to set a rotational speed of the mixing tool of the mixing device 101 and / or to open and close the first valve 108 of the mixing device 101.In addition, the control unit 112 can read out a turbidity value determined by means of the sensor 102, 106 and, as described above, determine a processing state of the suspension 111 and / or a condition of the produced container or a quality of the suspension and / or the quality of the container produced from the suspension 111 based on the turbidity value. It can also be provided that the control unit determines the processing state and the quality of the suspension and optionally additionally or alternatively determines the quality of the container produced from the suspension 111. This can be determined, for example, depending on variables to be used for controlling the device. If the processing state of the suspension is to serve as the closed-loop or open-loop control variable, at least this is determined.If the quality of the suspension or the container is to be used for this purpose, only this can be determined by the control unit or the processing state of the suspension can also be determined in addition. In one embodiment, it can be provided that the mixing device 101 is designed to feed the suspension of fiber-comprising material 111 to the shaping device 104 based on the processing state of the suspension of fiber-comprising material 111. For this purpose, the turbidity value determined by means of the sensor 102 can be compared with a target value and, based on the comparison, a decision can be made as to whether the desired processing state has been achieved or whether the quality of the suspension of fiber-comprising material 111 mixed in the mixing device 101 is sufficient or whether further mixing of the suspension of fiber-comprising material 111 is necessary before it can be fed to the shaping device 104.

[0083] If the determined turbidity value deviates from the specified target value by more than a certain threshold value, it can be determined that the suspension of fiber-comprising material 111 has not yet reached the desired processing state or does not have a sufficiently high quality, and the suspension 111 can be further mixed in the mixing device 101 and not fed to the molding device. In this case, the control unit 112 can be configured to keep the first valve 108 closed.

[0084] This may be the case, for example, if the suspension of fiber-comprising material 111 has not been mixed long enough in the mixing device 101, so that the average particle size of the solid portion of the suspension is larger than desired and / or the solid and liquid portions of the suspension 111 have not been sufficiently dispersed and further mixing of the suspension 111 is necessary to further reduce the particle size or to further disperse the components of the suspension 111.

[0085] However, this can also be the case if the suspension 111 has already been mixed in the mixing device 101 for a long enough time so that the solid and liquid portions of the suspension 111 have already been sufficiently dispersed and the solid portion has the desired particle sizes, but the solid portion in the suspension is too high or too low, so that the desired turbidity value cannot be achieved even with further mixing of the suspension 111.

[0086] In order to prevent an unnecessarily long downtime of the molding device 104 in this case and to increase the container throughput, it can be provided that if a first time interval is exceeded or if a change in the turbidity value within a second time interval is below a predetermined second threshold value, a solids content and / or a liquid content of the suspension of fiber-comprising material 111 in the mixing device 101 is changed. For example, in this case, the control unit 112 can determine, based on the determined turbidity value, whether the solids content of the suspension 111 is too high or too low and adjust it accordingly.For example, control unit 112 can also determine that a first solid component, such as the fiber-comprising material, is dispersed in the suspension in the desired amount, but that a second solid component, such as an additive, is dosed too high or too low. If the dosage of the second solid component is too low, it can be increased accordingly, for example. If the dosage of the second solid component is too low, the first solid component and the liquid component of the suspension 111 can be increased to adjust the dosage of the second solid component.

[0087] In one embodiment, it may be provided that if the determined turbidity value deviates from the target value by less than a predetermined threshold value, it is determined that the suspension of fiber-comprising material 111 has a sufficiently high quality and the suspension of fiber-comprising material 111 is fed to the molding device 104 via the supply line 103. For this purpose, the mixing device 101 can be configured to open the first valve 108 provided at the outlet connected to the supply line and to feed the suspension to the molding device.

[0088] After the suspension 111 has been fed to the molding device 104, it can be molded in the molding device 104 into a container made of fiber-comprising material. For this purpose, the molding device can, as already described above, comprise a mold with a cavity into which the suspension of fiber-comprising material is applied. The cavity can be perforated so that the liquid phase of the suspension of fiber-comprising material 111 can be led out of the mold again and the solid portion can be deposited on the wall of the cavity. The solid portion deposited on the wall can then be cured into a container by means of the curing device.

[0089] The portion of the suspension of fiber-comprising material 111 remaining during the formation of the container from the suspension 111 typically comprises mostly the liquid phase of the suspension 111, but may also comprise portions of the solids contained in the suspension, in particular solids which have a smaller size than the openings of the perforation of the mold cavity and can thus pass through the openings during formation. The molding device 104 may comprise a collecting trough in which the remaining portion of the suspension can be collected. As shown in Figure 1, the molding device 104 can be connected to the mixing device 101 by means of a return line 105, so that the portion of the suspension of fiber-comprising material 111 remaining during the formation of the container can be recycled and fed back to the mixing device 101.

[0090] A sensor 106 for determining the turbidity value of the returned portion of the suspension of fiber-comprising material 111 can be provided in the return line 105. The sensor 106 can be used to determine the processing state of the returned portion of the suspension 111. For example, a solids content and / or a liquid content, preferably a water content, can be determined in the returned portion of the suspension of fiber-comprising material 111. The solids content can be, for example, a proportion of the fiber-comprising material and / or an additive in the portion of the suspension 111.Based on the value thus determined, a solid or liquid content of the suspension of fiber-comprising material 111 in the mixing device 101 can then be adjusted to take into account the partial amount of the suspension 111 returned from the forming device 104 and to achieve a desired processing state of the suspension of fiber-comprising material 111 in the mixing device 101.

[0091] Furthermore, as already described above, based on a comparison of the turbidity value of the suspension of fiber-comprising material which was fed to the molding device and the turbidity value of the portion of the suspension of fiber-comprising material remaining in the molding device after molding, which portion can be returned to the mixing device 101 via the return line 105, a physical property of the manufactured container, such as a wall thickness, a wall thickness distribution and / or a weight of the manufactured container, can be determined.

[0092] Optionally, it can be provided that a filter 107 is arranged between the shaping device 104 and the sensor 106 in the return line 105. The filter 107 can be provided to filter out a solids content in the returned portion of the suspension of fiber-comprising material 111 down to a certain particle size. For example, the filter can be designed to filter out solids with a particle size d > 500 pm, d > 100 pm, d > 10 pm, or d > 0.1 pm from the returned portion of the suspension 111. Thus, the solids content in the portion of the suspension of fiber-comprising material 111 returned to the mixing device 101 can be reduced. In one embodiment, it can be provided that the mixing device 101 is connected to a plurality of shaping devices 104 via corresponding supply lines.For example, 5, 10, 20, or 50 molding devices can be connected to the mixing device, so that the throughput of containers produced in the device 100 can be increased. Each of the molding devices can, as described above, be connected to the mixing device 101 via a corresponding return line 105, so that the portion of the suspension of fiber-comprising material 111 remaining in the molding device 104 during container production can be recycled and fed back to the mixing device 101.According to the embodiment discussed above, a sensor 106 for determining the turbidity value of the returned portion of the suspension of fiber-comprising material 111 can be installed in the return lines. Based on the determined turbidity value, for example, a solid content, such as an additive content or a content of fiber-comprising material, or a liquid content, such as a water content, can be determined in the returned portion of the suspension 111. Based on this, a specific amount of solid and / or liquid can then be added to the suspension of fiber-comprising material in the mixing device in order to achieve a desired processing state of the suspension of fiber-comprising material 111 in the mixing device 101.

Claims

Claims 1. Device (100) for processing a suspension of material comprising fibers (111) to a container, comprising a mixing device (101) for mixing the suspension of fiber-comprising material, a forming device (104) for forming the suspension of fiber-comprising material into a container and a control unit (112), wherein the device (100) comprises at least one sensor (102, 106) for determining a turbidity value of the suspension of fiber-comprising material (111) and / or a partial amount of the suspension remaining after molding in the molding device, and the control unit (112) is designed to determine, based on the turbidity value, a processing state of the suspension of fiber-comprising material (111) in the mixing device and / or a condition of the container (101) produced.

2. Device (100) according to claim 1, wherein the sensor is arranged downstream (106) of the mixing device (101) and / or in (102) of the mixing device (101).

3. Device (100) according to claim 1 or 2, wherein the mixing device (101) is designed to supply the suspension of fiber-comprising material (111) to the molding device (104) based on the processing state of the suspension of fiber-comprising material (111).

4. Device (100) according to one of claims 1 to 3, wherein the mixing device (101) is designed, if the turbidity value deviates from a target value by more than a predetermined first threshold value, to further mix the suspension of fiber-comprising material (111) in the mixing device (101) and not to feed it to the molding device (104).

5. Device (100) according to claim 4, wherein the mixing device (101) is designed to change a solids content and / or a liquid content of the suspension of fiber-comprising material (111) in the mixing device (101) when a first time interval is exceeded or when a change in the turbidity value within a second time interval is below a predetermined second threshold value.

6. Device (100) according to one of claims 1 to 5, wherein the mixing device (101) is designed when the turbidity value of the suspension of material comprising fibers (111) deviates from a target value by less than a predetermined first threshold value, to feed the suspension of fiber-comprising material (111) to the molding device (104).

7. Device (100) according to one of claims 1 to 6, wherein the shaping device (104) is connected to the mixing device (101) via a return line (105), wherein the partial quantity of the supplied suspension of fiber-comprising material (111) remaining in the shaping device (104) after the container has been shaped can be returned from the shaping device (104) to the mixing device (101) via the return line (105), wherein the sensor (106) is arranged in the return line.

8. A method for processing a suspension of fiber-comprising material (111) into a container, wherein the suspension of fiber-comprising material (111) is mixed in a mixing device (101) and formed into a container in a forming device (104), wherein at least one sensor (102, 106) is provided for determining a turbidity value of the suspension of fiber-comprising material (111) and / or a partial amount of the suspension remaining after forming in the forming device, wherein a processing state of the suspension of fiber-comprising material (111) in the mixing device (101) and / or a quality of the produced container is determined by a control unit (112) based on the turbidity value.

9. The method according to claim 8, wherein the sensor is arranged downstream (106) of the mixing device (101) and / or in (102) of the mixing device (101).

10. The method according to claim 8 or 9, wherein the suspension of fiber-comprising material (111) is fed to the molding device (104) based on the processing state of the suspension of fiber-comprising material (111).

11. Method according to one of claims 8-10, wherein if the turbidity value deviates from a target value by more than a predetermined first threshold value, the suspension of fiber-comprising material (111) is further mixed in the mixing device (101) and is not fed to the molding device (104).

12. The method according to claim 11, wherein, if a first time interval is exceeded or if a change in the turbidity value within a second time interval is below a predetermined second threshold value, a solids content and / or a liquid content of the suspension of fiber-comprising material (111) is changed in the mixing device (101).

13. The method according to any one of claims 8 to 12, wherein, if the turbidity value of the suspension of fiber-comprising material (111) deviates from a target value by less than a predetermined first threshold value, the suspension of fiber-comprising material (111) is fed to the molding device (104).

14. Method according to one of claims 8 to 13, wherein the shaping device (104) is connected to the mixing device (101) via a return line (105), wherein the partial quantity of the supplied suspension of fiber-comprising material (111) remaining after the container has been shaped in the shaping device (104) is returned from the shaping device (104) to the mixing device (101) via the return line (105), wherein the sensor (106) is arranged in the return line (105).

15. The method according to any one of claims 8 to 14, wherein based on the turbidity value, a proportion of an additive in the suspension of fiber-comprising material (111) is determined.

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