Method and apparatus for the process-optimized production of manufactured wood boards

Abstract

The invention relates to a method and an apparatus for the process-optimized production of manufactured wood boards, in particular particle boards. In order to provide a method and an apparatus for the process-optimized production of manufactured wood products which make it possible to optimize quality while providing continuous quality assurance, which allow the best possible control variables to be determined particularly easily and quickly, and which also guarantee continuous production that results in the lowest possible wastage while maintaining the highest possible level of process stability, the invention provides the following: at least one process parameter, in particular the water content and / or the pH value, is measured in the course of the method by means of near-infrared spectroscopy and the measured values of the at least one process parameter are then sent to a control unit for process optimization and / or process-optimized control of the method, wherein the measurement of the at least one process parameter is taken at one or more positions, selected from: a position immediately upstream of the gluing, in particular between a dry raw chip hopper and the gluing station; a position immediately downstream of the gluing, in particular between the gluing station and a chip material distributor and / or a dispersing station; a position in the provision phase immediately downstream of a timber yard, in particular between the timber yard and a subsequent dryer; and / or a position in the provision phase immediately downstream of a dryer, in particular between the dryer and a sieving station and / or a dry raw chip hopper.

Description

[0001] (20147-8)

[0002] Description

[0003] METHOD AND DEVICE FOR PROCESS-OPTIMIZED PRODUCTION OF WOOD-BASED PANELS

[0004] The invention relates to a method and a device for the process-optimized production of wood-based panels, in particular particleboard.

[0005] Methods and devices for manufacturing wood-based panels, and in particular particleboard, are already known in various forms from the prior art. Operating such a method requires selecting numerous settings and control parameters, which depend on a multitude of influencing factors, such as the type of wood, the moisture content of the wood used, the pH value, the particle size, the type and composition of the adhesive used, the amount of adhesive, the amount of water added, the process and pressing temperature, the pressing pressure, the pressing time, and other parameters.

[0006] In the prior art, regular quality control of the finished wood-based panels is therefore carried out, as well as close monitoring of the quality after any changes are made to the manufacturing process. However, this approach already has the disadvantage that the equipment and processes of the prior art are typically operated continuously, meaning that by the time a finished wood-based panel is quality-controlled, a significant quantity of such panels has already been produced. Therefore, before the process parameters are optimally adjusted, a considerable number of wood-based panels have already been produced, at least with reduced quality, and in the worst case, as rejects.Furthermore, changes in influencing factors during ongoing production, such as changes in the quality, wood species composition and / or moisture content of the raw chip material supplied, can also lead to a reduction in product quality, which may only be detected with a considerable time delay.

[0007] Furthermore, the disadvantage of the prior art methods and devices is that only within the framework of a relatively long process, involving changes to control parameters and subsequent quality controls of the finished wood-based panels, can a set of control parameters be found that leads to a high-quality product.

[0008] The invention is therefore based on the objective of providing a method and a device for the process-optimized production of wood-based panels, which allow for quality optimization as well as continuous quality assurance, enable a particularly simple and quick determination of the best possible control parameters and also ensure continuous production with the lowest possible waste and the greatest possible process stability.

[0009] The object of the invention is achieved by a method for the process-optimized production of wood-based panels according to claim 1 and by a device for the process-optimized production of wood-based panels according to claim 10. Advantageous embodiments of the invention are specified in the dependent claims.

[0010] The inventive method for the process-optimized production of wood-based panels, in particular particleboard, comprises the following process steps: first, the provision of raw chip material from a wood yard and / or from a dryer and / or from a dry raw chip bunker; second, the application of glue to the raw chip material, in particular within a gluing station; third, the spreading of the glued chip material to form a strand, in particular in a spreading station and / or onto a conveyor belt; and finally, the pressing, in particular continuous pressing, of the strand into a wood-based panel. The invention provides that at least one process parameter, in particular the moisture content and / or the pH value, is measured by means of near-infrared spectroscopy and the measured values ​​of the at least one process parameter are transmitted to a control unit for process optimization and / or for process-optimized control of the method.the production of the wood-based panel, wherein the measurement of at least one process parameter is carried out at one or more positions, selected from a position immediately before gluing, in particular between a dry raw chip bunker and the gluing station, a position immediately after gluing, in particular between the gluing station and a chip distributor and / or a spreading station, a position during the supply immediately after a wood yard, in particular between the wood yard and a subsequent dryer, and / or a position during the supply immediately after a dryer, in particular between the dryer and a screening station and / or a dry raw chip bunker.

[0011] The device according to the invention for the process-optimized production of wood-based panels, and preferably particleboard, particularly by means of the method according to the invention, preferably comprises a wood storage area and / or a dry raw chip bunker for providing raw chip material, at least one gluing station for applying glue to the raw chip material, at least one spreading station for spreading the glued chip material to form a strand, particularly onto a conveyor belt, and a press, particularly a continuous press, for pressing the strand into a wood-based panel. Furthermore, the device comprises at least one near-infrared measuring device for measuring at least one process parameter, in particular the moisture content and / or pH value, and preferably also at least one control unit to use the measured values ​​of the at least one process parameter for process optimization and / or for process-optimized control of the method.to be used in the production of the wood-based panel, wherein a near-infrared measuring device or several near-infrared measuring devices are arranged immediately before the gluing station, in particular between a dry raw chip bunker and the gluing station, immediately after the gluing station, in particular between the gluing station and a chip material distributor and / or the spreading station, immediately after the wood yard, in particular between the wood yard and a subsequent dryer, and / or immediately after a dryer, in particular between the dryer and a screening station and / or the dry raw chip bunker.

[0012] The method and apparatus according to the invention enable a particularly fast and efficient optimization of the manufacturing process for wood-based panels based on process parameters measured by near-infrared spectroscopy. This allows for a simple improvement in quality and subsequent quality assurance.

[0013] 5 By significantly reducing the reaction time to suboptimal settings and control variables, the amount of scrap resulting from continuous production can be reduced, and process stability can be increased, even with changing materials used, such as the raw chip material and the adhesive.

[0014] 10

[0015] According to the invention, a process-optimized manufacturing of wood-based panels is understood to be a process in which it is possible to optimize at least one control variable of the manufacturing process based on measured values ​​of at least one process parameter, in particular as the primary control variable of the process optimization, such that a wood-based panel of higher quality and / or with consistently high quality can be obtained despite a change in process parameters. The primary or preferred process parameters are the moisture content and / or pH value of the measured material, in particular the raw chip material, the glued chip material, and / or the formed strand.

[0016] 20

[0017] The provision of raw chip material refers to a process that ultimately yields chip material which can be used directly in the production of wood-based panels. This provision can involve transporting raw chip material from a lumberyard and / or

[0018] 25. Subsequent drying of the raw chip material coming from the wood yard and / or screening of the preferably dried raw chip material in a screening station and / or storage of the preferably dried and / or screened raw chip material in a drying chip bunker. Furthermore, at any process position, preferably between the wood yard and the dryer,

[0019] 30 and / or immediately following the dryer, a means for shredding the wood or the coarse chip material should also be provided.

[0020] According to the invention, the raw chip material is coated with at least one adhesive.

[0021] The material is preferably provided with exactly one adhesive, which is preferably carried out in a gluing station, which particularly preferably includes a gluing mixer. Although the gluing can be carried out in any way, at least one adhesive and preferably exactly one adhesive are preferably applied to the moving raw chip material.

[0022] 5. Adhesive is added, preferably by spraying, particularly within a glue mixer and / or by means of a tool moving, particularly rotating, inside a stationary mixer. At the same time, water can also be added to the raw chip material, preferably also by spraying, particularly within a glue mixer. Preferably

[0023] 10 the adhesive used is a urea-formaldehyde resin, a melamine-formaldehyde resin, a melamine urea formaldehyde (MUF) or a melamine-urea-formaldehyde resin or an isocyanate.

[0024] From the glued chip material, a shaped strand is subsequently produced by sprinkling the chip material in one or more layers. This strand is then formed into a wood-based panel by pressing and preferably also heating. The pressing is preferably carried out in a continuously operated press or a constant press. Following pressing, the panel is preferably cut to the desired dimensions.

[0025] 20

[0026] The measurement of at least one process parameter for subsequent process optimization is preferably carried out without contact and in such a way that the measured material can subsequently still be used for the production of a wood-based panel. According to the invention, at least part of this measurement-

[0027] 25 gen and preferably all measurements using near-infrared spectroscopy (NIRS).

[0028] Near-infrared spectroscopy within the meaning of the invention is generally understood to be a spectroscopic investigation that analyzes the material to be investigated also in the near-infrared range and preferably exclusively in the near-infrared range.

[0029] 30. The near-infrared range is preferably understood to be the wavelength range between 700 nm and 3000 nm, particularly preferably between 760 nm and 2500 nm, and most preferably between 780 nm and 2500 nm. Near-infrared spectroscopy is primarily used to determine the moisture or water content of the

[0030] £ of wood, the provided wood chips, the already moistened and / or glued wood chips and / or any material used in any process step of the manufacture of a wood-based panel.

[0031] Near-infrared spectroscopy is preferably performed using a near-infrared spectrometer, although measurement using only a near-infrared spectroscope would also be conceivable. Accordingly, the near-infrared measuring device according to the invention is preferably a near-infrared spectroscope or a near-infrared spectrometer and / or preferably an online near-infrared measuring device, which is particularly preferably configured to perform near-infrared measurements continuously or periodically. Additionally, event-driven measurements can also be performed, for example, when a user triggers such a measurement and / or when a deterioration in product quality is detected during automatic or manual quality control.

[0032] According to the invention, a near-infrared measuring device is arranged at at least one, preferably several, and particularly preferably all system- or process-relevant positions of the raw chip production process and / or the manufacturing process of the wood-based panel. A process-relevant position is generally understood to be any position at which the properties and measurable process parameters of the measured material have changed compared to a previous measurement position. Particularly relevant positions include the position after the raw chip material has been provided, before and / or after gluing, before and / or after the application of the glued chip material, and / or immediately before and / or after pressing the glued and applied chip material. Furthermore, a near-infrared measuring device for measuring immediately after gluing is preferably arranged between the gluing station and a chip material distributor and / or a spreading station.Accordingly, it is preferred that the near-infrared measuring device is located downstream of and / or not within the gluing station and / or that the measurement using the near-infrared measuring device is carried out after completion of the gluing process.

[0033] Preferably, a near-infrared measuring device is arranged at at least two system- or process-relevant positions in the raw chip production process and / or the manufacturing process of the wood-based panel. It is particularly preferred that these two positions are selected from a position for measuring the raw chip material immediately before gluing, in particular between a dry raw chip hopper and the gluing station, and / or a position immediately after gluing between the gluing station and a chip material distributor and / or a spreading station, and / or a position during the supply of chip material immediately after a wood storage area, in particular between the wood storage area and a subsequent dryer, and / or a position during the supply immediately after a dryer, in particular between the dryer and a screening station and / or a dry raw chip hopper.

[0034] The optimization of the manufacturing process ultimately takes place within a control unit, which can be located directly on the device or separately. Preferably, the control unit is a programmable logic controller (PLC), but it can also be any other computing unit, a computer, or even a data center. The process optimization is based on at least some of the measured values ​​of at least some of the process parameters. Preferably, the optimization is based on all measurable or measured process parameters and / or takes into account all measured values ​​of the respective process parameter.

[0035] In a preferred embodiment of the inventive process, in addition to the water content and / or pH value, the amount of adhesive applied to the raw chip material and / or the wood species are also measured as process parameters using near-infrared spectroscopy. Preferably, the measurement is not limited to the adhesive, particularly before the adhesive is added to the raw chip material and / or before gluing. Accordingly, it is preferred that at least one measurement, preferably several measurements, particularly preferably the majority of measurements, and most preferably all measurements, particularly using near-infrared spectroscopy and / or a single near-infrared measuring device, are performed on the glued chip material, after the raw chip material has been glued, and / or directly on the chip material or the raw chip material.Particularly preferably, two measurements are taken, especially by means of near-infrared spectroscopy and / or by means of a single near-infrared measuring device, before pressing the extrusion into a wood-based panel and / or before finishing a wood-based panel. Furthermore, preferably not one measurement, and in particular not exclusively one measurement, is carried out to measure one or more components of the adhesive, especially the synthetic resin content of such an adhesive.

[0036] 5

[0037] In principle, each process parameter can be measured using near-infrared spectroscopy and / or a single near-infrared measuring device. Furthermore, several, and in particular all, process parameters can be measured simultaneously or using a single near-infrared measuring device. Preferably, each

[0038] 10. A near-infrared measuring device records all process parameters that can be meaningfully measured at the respective position in the process. For example, measuring the amount of adhesive is only meaningful after the raw chip material has been glued. The same applies to all process parameters. A preferred embodiment of the invention provides that the moisture content or water content is measured at at least two positions, particularly preferably at three positions, and most preferably at each individual position. This is advantageous because this process parameter can change continuously during the process due to the process flow and, in particular, due to the addition of water and / or drying caused by heat input. Multiple wood species determinations initially appear feasible only at a single position.

[0039] 20 is useful because the composition should not change during the process; however, when using different wood species, information about the uniform distribution and successful mixing or segregation can also be obtained during the process. Accordingly, the wood species can be measured only once, but also multiple times or even using any near-infrared measuring device.

[0040] 25 councils will be held.

[0041] An advantageous further development of the method according to the invention provides that a measurement using near-infrared spectroscopy is carried out at least immediately after the gluing of the raw chip material in order to obtain information about the saturation on the raw chip material.

[0042] 30. The amount of adhesive applied to the chip material and / or the current moisture content of the glued chip material are to be obtained. The information about the amount of adhesive applied to the raw chip material is preferably also obtained by determining the moisture content, whereby if the moisture content is known before the

[0043] By applying glue and, if necessary, adding a known quantity of additional water at the gluing station, the amount of adhesive in the glued chip material can be determined. Using the process parameters measured at this stage of the process, the amount of adhesive and / or additional water added can then be controlled almost in real time.

[0044] Although measurements of at least one process parameter using near-infrared spectroscopy can be performed at any point in the process, it is preferred that at least one further measurement of the at least one process parameter using near-infrared spectroscopy be performed after the application of the glued chip material or after the spreading station and before pressing into a wood-based panel. Measuring immediately before the press enables complete optimization of the manufacturing process, since the material properties of the finished wood-based panel result directly from the properties of the glued chip material before pressing.

[0045] In order to advantageously minimize the amount of rejects or produced wood-based panels with suboptimal product properties or not of the highest product quality, a process optimization is carried out in an advantageous embodiment of the inventive method based on the process parameters measured by means of near-infrared spectroscopy, in particular by means of the control unit, so that an adaptation of the method for producing wood-based panels is made possible within a period of less than 20 minutes, preferably less than 15 minutes, particularly preferably less than 10 minutes and most preferably less than 5 minutes.

[0046] According to a preferred embodiment of the inventive method, the individual process parameters are correlated with their respective control variables for process optimization. Preferably, the measured values ​​of the process parameters from all near-infrared measuring devices are used within the control unit to calculate the control variables, and the calculated control variables are used for the controlled operation of the method for producing wood-based panels and / or a device for producing wood-based panels. Accordingly, a retrograde correlation of the measured values ​​of the process parameters within the manufacturing process is preferred.

[0047] In principle, it is still conceivable that each process parameter is assigned exactly one control variable, or that one or more control variables are calculated using several or all process parameters. A direct correlation exists, for example, between a measured wood species and the control of the addition and / or mixing of the supplied raw chip material. In contrast, the amount of adhesive added and / or the adhesive composition and / or the amount of water to be added during gluing can be determined depending on several process parameters. In particular, the water content at various points in the process, but also the wood species used, the pH value, and / or the amount of adhesive remaining on the chip material after gluing can be crucial here. Depending on the pH value, the amount of adhesive, the adhesive composition, and / or the type of adhesive can also be adjusted.

[0048] Furthermore, based on the measured values ​​of the process parameters, adjustments can be made to other control variables, such as the pressing time, the pressing pressure, the pressing temperature, the amount of glued chip material to be applied and / or the transport speed.

[0049] Process optimization, particularly in the control unit, is preferably implemented as a self-learning process, an automatically controlled process, and / or using artificial intelligence, preferably allowing user intervention, especially in the form of configurable offset values ​​and / or limit values. Process optimization as an automatically controlled process preferably involves controlling the process to defined target values, such as a target moisture content and / or a target sizing quantity, at a defined point in the process. The limit values ​​defined by the user can be minimum and / or maximum values ​​for a target variable, particularly to keep the process within desired and / or technically feasible limits.

[0050] To optimize the process, a data model is preferably created in the control unit, the programmable logic controller (PLC), and / or any other computer. Additionally or alternatively, a database can be created containing the recorded measurements, other recorded process variables, and / or the control variables of the process flow, as well as, if applicable, data from subsequent quality control of the wood-based panels. Such a database then makes it particularly easy to subsequently perform optimization using self-learning processes or artificial intelligence, whereby the developed models and / or identified correlations can be fed back into the real-time control of the manufacturing process.

[0051] An advantageous embodiment of the method according to the invention further provides that, immediately before at least one, preferably several, and particularly preferably all measurements using near-infrared spectroscopy, the material to be measured, in particular the raw chip material, the glued chip material, and / or the forming strand, is leveled. The leveling is preferably carried out using a stripping plate or a leveling plate, which particularly preferably extends at least over the area to be measured and most preferably over the entire width of the material to be measured. The stripping or leveling plate extends over the material to be measured in such a way that a uniform layer thickness, a flat surface, a uniformly compacted packing, and / or a uniform surface is achieved.Accordingly, equalization increases the quality and reliability of the measured values, whereby a constant distance between the measured material and the near-infrared measuring device is particularly important.

[0052] Finally, a preferred embodiment of the inventive method is one in which, for the production of a wood-based panel with at least one face layer and at least one middle layer, the provision of raw chip material and the gluing of the raw chip material for the face layer and the middle layer are carried out separately, and for the production of multi-layered wood-based panels, the material for the individual layers is then spread successively. Preferably, the wood-based panel has a middle layer and a face layer on each side of the middle layer, wherein the face layers can be identical and / or different in composition. If the two face layers have an identical composition and / or gluing, it is preferred that all face layers or all layers with identical composition are provided and glued together.Furthermore, preferably, the process steps, including measurements using near-infrared spectroscopy, are carried out separately for each composition of the chip material and / or for the at least one top layer and the at least one middle layer, in accordance with the invention.

[0053] Preferably, the glued chip material for the individual layers is joined immediately before pressing and / or in a respective spreading station. Particularly preferably, along a transport direction, a spreading station is provided first for a bottom cover layer, followed by at least one spreading station for the middle layer, and finally another spreading station for a top cover layer, wherein the two spreading stations for the two cover layers can be supplied together with identical, glued chip material and / or from a single distributor and / or a single gluing station.

[0054] Particularly preferably, the application of the glued chip material for the middle layer is carried out by means of a first spreading station for the chip material of the lower half of the middle layer, followed by a second spreading station for the chip material of the upper half of the middle layer. It is again preferred that the two spreading stations for the two middle layer halves are supplied together with identical, glued chip material and / or from a single distributor and / or a single gluing station.

[0055] An advantageous embodiment of the device according to the invention provides that, in addition to the near-infrared measuring device(s) according to the invention, a further near-infrared measuring device is arranged after the spreading station and before the press, and / or a device for measuring the moisture content of the raw chip material is provided at the wood yard and / or after a dryer for the raw chip material and / or before a screening station for the raw chip material. The device for measuring the moisture content of the raw chip material can determine the moisture or water content of the raw chip material in any desired manner, although preferably not by means of near-infrared spectroscopy. Furthermore, it is preferred that measuring the raw chip material by means of near-infrared spectroscopy and / or by means of a single near-infrared measuring device in the area of ​​the wood yard and / or during the supply immediately after a wood yard is not carried out as part of a control of recycled material and / or

[0056] 5. The recycling of wood material takes place. Accordingly, it is preferred that this measurement is carried out after the wood yard on the complete raw chip material transported from the wood yard and / or intended for gluing.

[0057] Regarding the measurement of materials using near-infrared spectroscopy, there are fundamental…

[0058] 10. There are two different possibilities. Firstly, the measurement can be carried out during the ongoing manufacturing process, and in particular without disrupting the manufacturing process and / or on the material directly used in the manufacturing process. Secondly, material to be measured can be removed or separated from the manufacturing process, whereby it is also conceivable to return the previously measured material to the manufacturing process.

[0059] Accordingly, a design of the device according to the invention is preferred in which at least one measurement by means of near-infrared spectroscopy is performed directly on the material.

[0060] 20 rial in the manufacturing process and / or without prior separation or diversion of the material to be measured, wherein the material flow to be measured is preferably not slowed down and / or equalized before, in particular immediately before, the measurement.

[0061] 25 Alternatively or additionally, for at least part of the measurements to be carried out, a conveying device for the material to be measured by near-infrared spectroscopy may also be provided and / or the material to be measured may be removed from the other material, in particular the other raw chip material or the other glued chip material, before the measurement. In this configuration of the device-

[0062] 30. In the process, the material to be measured is first separated and preferably fed into a bypass section and measured there, with the measured material being particularly preferably subsequently returned to the manufacturing process. The conveying device is preferably a conveyor belt and / or has

[0063] £ ribs running perpendicular to the direction of transport.

[0064] Separating or diverting the material to be measured allows for a particularly simple process of leveling and / or smoothing the material and / or bringing it to a predetermined strand thickness or density, which may differ from the original strand. Furthermore, slowing down or even temporarily stopping the material to be measured, especially for measurement purposes, is conceivable, although measuring without slowing down is generally preferred.

[0065] It is also conceivable that some of the measurements using near-infrared spectroscopy could be performed with separated material, while others could be carried out directly within the process. Separating the material is particularly advantageous for the freshly glued chip material immediately following the gluing process or directly after the gluing station.

[0066] Finally, an advantageous embodiment of the device according to the invention provides that at least one near-infrared measuring device, preferably some of the near-infrared measuring devices, and particularly preferably all near-infrared measuring devices, are arranged in a height-adjustable manner and / or traversing on a rail, in particular being displaceable at right angles to the transport direction of the material to be measured. The height adjustment and / or traversing can be carried out manually, although it is preferred that this is additionally or exclusively motorized, in particular to enable precise positioning at one or more measuring positions.The height setting is preferably configured such that the surface of the material to be measured, in particular regardless of the layer thickness of the material to be measured, can generally be measured from a height between 50 mm and 750 mm, particularly preferably between 100 mm and 500 mm, most preferably between 200 mm and 300 mm and particularly from a height of 250 mm.

[0067] An exemplary embodiment is described in more detail below with reference to the drawing. Figure 1 shows a schematic diagram of the arrangement of the individual components and the sequence of the manufacturing process, including the positions of the respective near-infrared spectroscopy measurements.

[0068] In a schematically and simplified representation of a particleboard production plant shown in Fig. 1, raw wood chips are first transported from a wood storage area 1 towards a dryer 2. During transport on a conveyor belt, the raw wood chips are leveled by means of a scraper plate and then measured by a first near-infrared measuring device 9a from a distance of approximately 25 cm during transport. From the measurement data, at least the wood moisture content, and preferably also the wood species and, if necessary, the pH value, are determined as process parameters.

[0069] In dryer 2, the raw chip material is dried, and subsequently, another measurement is taken using a near-infrared measuring device 9b, determining the same process parameters as before drying. The difference at this stage is that the raw chip material to be measured is separated from the rest of the material stream before measurement with the near-infrared measuring device 9b and transported to the device via a ribbed conveyor belt. During this process, the raw chip material is at least slowed down and, if necessary, temporarily stopped, for example, to allow the dried raw chip material to cool completely and / or evaporate before measurement. Furthermore, the material is leveled again before measurement. After measurement, the measured raw chip material is returned to the rest of the raw chip material.

[0070] After drying in dryer 2, the dried raw chip material is screened in a screening station 7 and then fed to a raw chip bunker 3a for the surface layer material and a raw chip bunker 3b for the core layer material. To form a multi-layer particleboard and / or a particleboard with a core layer that differs from the two outer surface layers, it is advantageous to process the material for the two surface layers and the at least one core layer separately after screening. The core layer may have a different particle size distribution and / or average particle size, a different quality of the raw chip material, and / or a different wood composition.

[0071] Upon exiting the respective raw chip bunker 3a, b, the dried and sieved raw chip material is measured again using a near-infrared measuring device 9c, e, whereby the wood moisture content and / or the pH value are preferably determined again as process parameters. The raw chip material is then fed to a gluing station 4a, b and mixed there in a glue mixer with a defined quantity of adhesive and, if necessary, a small quantity of water using a rotating tool. Upon exiting the gluing station 4a, b, a further measurement is then carried out using a near-infrared measuring device 9d, f, in particular to determine the amount of adhesive applied and remaining on the chip material as a process parameter. Preferably, the moisture content of the glued chip material and, if necessary, the pH value are also determined again.

[0072] The surface layer material and the core layer material are then fed to four spreading stations 5a, b via respective chip material distributors 6a, b, where a strand of material is spread layer by layer to form a particleboard. Between the spreading of the chip material for a portion or all individual layers and / or after spreading and thus the completion of the strand's formation, a further measurement is taken using a near-infrared measuring device 9g. Finally, the strand is pressed into a particleboard, in particular in a continuous press 8.

[0073] To minimize downtime during production changes, which can occur three times a day, for example, and to ensure consistently high-quality particleboard production even with changing raw materials such as slight variations in wood composition, wood species, or wood moisture content, and / or changing environmental parameters such as ambient temperature or humidity, it is planned that all measured values ​​of the process parameters, in particular the wood species, moisture content, pH value, and applied adhesive quantity, recorded by the near-infrared measuring devices 9a-g, will be transmitted to a control device. From there, automatic process optimization and control of the individual process steps will take place in real time using the measured process parameters as control variables.Naturally, measured values ​​and data from the system and other sensors can also be taken into account. It is advantageous to create a data model of the process flow using data measured over a longer period and stored in a database, taking into account the variations of all process parameters. This can also be done using artificial intelligence.

[0074] (20147.8)

[0075] Reference symbol list

[0076] 5

[0077] 1 lumberyard

[0078] 2 dryers

[0079] 3a Raw chip bunker for top layer material io 3b Raw chip bunker for middle layer material

[0080] 4a Gluing station for top layer material

[0081] 4b Gluing station for middle layer material

[0082] 5a Spreading station for surface course material

[0083] 5b Spreading station for middle layer material

[0084] 6a Chip material distributor for top layer material

[0085] 6b Chip material distributor for middle layer material

[0086] 7 Sieving station

[0087] 8 Press

[0088] 9a - g Near-infrared measuring device

[0089] 20

[0090] £

Claims

(20147-8) Claims 1. Method for the process-optimized production of wood-based panels, in particular particleboard, comprising the following steps: Providing raw chip material from a wood yard (1) and / or from a dryer (2) and / or from a dry raw chip bunker (3a, b), gluing the raw chip material, in particular within a gluing station (4a, b), Spreading the glued chip material to form a shaped strand in a spreading station (5a, b) and / or onto a conveyor belt, Pressing the forming strand into a wood-based panel, characterized in that at least one process parameter, in particular the moisture content and / or the pH value, is measured by means of near-infrared spectroscopy and the measured values ​​of the at least one process parameter are sent to a control unit for process optimization and / or for process-optimized control of the process, wherein the measurement of the at least one process parameter takes place at one or more positions selected from a) immediately before gluing, in particular between a dry raw chip bunker (3a, b) and the gluing station (4a, b), b) immediately after gluing, in particular between the gluing station (4a, b) and a chip material distributor (6a, b) and / or a spreading station (5a, b), c) during the supply immediately after a wood storage area (1), in particular between the wood storage area (1) and a subsequent dryer (2),and / or d) when providing immediately after a dryer (2), in particular between the dryer (2) and a screening station (7) and / or a dry raw chip bunker (3a, b).

2. Method for the process-optimized production of wood-based panels according to claim 1, characterized in that, in addition to the water content and / or the pH value, the amount of adhesive applied to the raw chip material and / or the type of wood are also measured as process parameters using near-infrared spectroscopy.

3. Method for the process-optimized production of wood-based panels according to claim i or 2, characterized in that at least immediately after the gluing of the raw chip material, a measurement is carried out using near-infrared spectroscopy in order to obtain information about the amount of adhesive applied to the raw chip material and / or about the current moisture content of the glued chip material.

4. Method for the process-optimized production of wood-based panels according to at least one of the preceding claims, characterized in that at least one further measurement of the at least one process parameter is carried out by means of near-infrared spectroscopy after the sprinkling of the glued chip material and before pressing to form a wood-based panel.

5. Method for the process-optimized production of wood-based panels according to at least one of the preceding claims, characterized in that, based on the process parameters measured by means of near-infrared spectroscopy, a process optimization is carried out by means of the control unit, so that an adaptation of the method for the production of wood-based panels is made possible within a period of less than 15 minutes.

6. Method for the process-optimized production of wood-based panels according to at least one of the preceding claims, characterized in that, for process optimization, the individual process parameters are correlated to the respective control variables, wherein preferably all values ​​of the process parameters measured by means of near-infrared spectroscopy are taken within the control unit. The parameters are used to calculate the control variables, and the calculated control variables are used for the controlled operation of the process.

7. Method for the process-optimized production of wood-based panels according to at least one of the preceding claims, characterized in that the process optimization in the control unit is carried out as a self-learning process, as an automatically controlled process and / or using artificial intelligence, preferably enabling user intervention, in particular in the form of storable offset values ​​and / or limit values.

8. Method for the process-optimized production of wood-based panels according to at least one of the preceding claims, characterized in that the material to be measured is equalized immediately before at least one measurement by means of near-infrared spectroscopy.

9. Method for the process-optimized production of wood-based panels according to at least one of the preceding claims, characterized in that, for the production of a wood-based panel with at least one top layer and at least one middle layer, the provision of raw chip material and the gluing of the raw chip material for the top layer and the middle layer are carried out separately, and for the production of multi-layered wood-based panels, the material is then sprinkled onto the individual layers one after the other.

10. Device for the process-optimized production of wood-based panels, in particular particleboard, comprising a means for feeding raw chip material from a wood storage area (i) and / or from a dry raw chip bunker (3a, 3b), at least one gluing station (4a, b) for gluing the raw chip material, at least one spreading station (5a, b) for spreading the glued chip material to form a shaped strand, - 22 - a press (8) for pressing the forming strand into a wood-based panel, characterized by at least one near-infrared measuring device (9a - f) for measuring at least one process parameter, in particular the water content and / or the pH value, wherein one or more near-infrared measuring devices (9a - f) are arranged a) immediately before the gluing station (4a, b), in particular between a dry raw chip bunker (3a, b) and the gluing station (4a, b), b) immediately after the gluing station (4a, b), in particular between the gluing station (4a, b) and a chip material distributor (6a, b) and / or the spreading station (5a, b), c) immediately after the wood yard (1), in particular between the wood yard (1) and a subsequent dryer (2), and / or d) immediately after a dryer (2), in particular between the dryer (2) and a screening station (7) and / or the dry raw chip bunker (3a, b).

11. Device for the process-optimized production of wood-based panels according to claim 10, characterized in that a near-infrared measuring device (9g) is additionally arranged after the spreading station (5a, b) and before the press (8) and / or a device for measuring the moisture content of the raw chip material is provided at the wood storage area (1) and / or after a dryer (2) for the raw chip material and / or before a sieving station (7) for the raw chip material.

12. Device for the process-optimized production of wood-based panels according to claim 10 or 11, characterized in that a conveying device is provided for the material to be measured by means of near-infrared spectroscopy and / or the material to be measured is removed from the remaining material, in particular the remaining raw chip material or the remaining glued chip material, before the measurement.

13. Device for the process-optimized production of wood-based panels according to - 23 - at least one of claims 10 - 12, characterized in that at least one measurement by means of near-infrared spectroscopy is carried out directly on the material in the manufacturing process and / or without prior separation of the material to be measured, wherein the material flow to be measured is preferably equalized and / or not slowed down before the measurement.

14. Device for the process-optimized production of wood-based panels according to at least one of claims 10 - 13, characterized in that at least a part of the near-infrared measuring devices (9a - g) and preferably all near-infrared measuring devices (9a - g) are height-adjustable and / or arranged traversing on a rail.

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