Apparatus and method for providing a moist material to be dried - Patent Application 20070122997

Abstract

An apparatus for providing a moist material to be dried includes at least a material supply unit (102), a plurality of nozzles (104), and a drying surface (106), the drying surface being configured to be movable relative to the plurality of nozzles. The material supply unit is configured to direct the moist material through the plurality of nozzles and onto the drying surface to obtain a plurality of elongated, string-like accumulations of material (108). The apparatus additionally includes at least one imaging device (110) configured to obtain imaging data of at least one of the elongated, string-like accumulations of material, and at least one control unit (112) configured to determine at least one characteristic of at least one of the elongated, string-like accumulations of material, the control unit additionally configured to facilitate performance of at least one action based on the determined characteristic.

Description

[Technical Field]

[0001] The present invention relates generally to drying processes and apparatus, and more particularly to providing a wet material to be dried in which imaging data is utilized to determine at least one property of the wet material. [Background technology]

[0002] Many processes and equipment involving the production of materials that dry the materials to produce an end product are susceptible to different types of malfunctions or defects within the equipment or in the manner in which the process is carried out, which can lead to a variety of problems in the process and / or the quality of the dried material produced.

[0003] As new types of processes for material production are developed, it is also important to devise methods for the management of malfunction situations associated with the machines involved. In a related aspect, it is preferable to be aware of the quality of the material produced. The material produced may be manually inspected by humans, which is time-consuming, labor-intensive, and involves high costs. Detection of malfunctions or process-related defects would also be beneficial in order to avoid or at least reduce the production of substandard quality material at an early stage of the process.

[0004] Methods for producing materials are known that involve directing a moist material through a plurality of nozzles to obtain a plurality of elongated strands of material that are then dried. More specifically, such methods can be utilized to produce filaments that can be further used to produce textiles, for example.

[0005] If a malfunction of a piece of machinery involved is detected, the material production process may be stopped until the machinery is repaired to avoid producing poor quality material. However, stalling the production process is time-consuming and causes loss of revenue. If the quality of the material produced is undesirable and a process defect or machinery malfunction is determined, it may also be difficult to determine where in the process or machinery the failure occurred. Finding the malfunctioning piece of equipment can be time-consuming, and during this time the manufacturing process may remain stalled, which is undesirable. Summary of the Invention

[0006] It is an object of the present invention to alleviate at least some of the problems in the prior art. According to one aspect of the present invention, there is provided an apparatus for providing a moist material to be dried, the apparatus comprising at least: a material supply unit; A plurality of nozzles; a drying surface configured to be movable relative to the plurality of nozzles; a material supply unit configured to receive or provide a wet material and direct the wet material through a plurality of nozzles to a drying surface to obtain a plurality of elongated strand-like accumulations of material; The device, at least one imaging device configured to acquire imaging data of at least one of the elongated strand-like accumulations of material; and at least one control unit configured to determine at least one characteristic of at least one of the elongated string-like material accumulations based on the imaging data, the control unit being additionally configured to facilitate performance of at least one action based on the determined characteristic.

[0007] In accordance with the present invention, a moist material can be dried or provided for drying, and at least one characteristic of the moist material can be determined essentially without human input and in an automated manner during the process as it is being performed by acquiring image data relating to a plurality of elongated, strand-like accumulations of material that are provided.

[0008] Human inspection of materials provided for drying or dried materials may be reduced or avoided, which may lead to reduced requirements for human labor, and properties may be determined faster and / or more efficiently than by a human operator.

[0009] At least one characteristic may be determined, evaluated, or monitored essentially continuously (which also refers to occurring at predetermined time intervals) by acquiring multiple images (or imaging data may be acquired essentially continuously or at predetermined time intervals), so that one or more actions may be efficiently performed on the fly as the process is being executed.

[0010] The imaging data and / or the determined property may be associated with a particular time or time interval. For example, the imaging data may be associated with a timestamp. Thus, for example, a change in a determined property may be associated with a particular sub-process in the drying process based on correlating a time, time interval, or timestamp with that sub-process. It may then be determined which sub-process caused the change in the property.

[0011] In accordance with the present invention, imaging database characterization may provide a way to obtain information about multiple properties or characteristics related to the drying process, the equipment, and / or the material being dried using only one inspection method. Obtaining such information by other methods than an imaging device may be much more complex, requiring, for example, many sensors.

[0012] By acquiring imaging data, it can be efficiently determined which individual accumulation of elongated, string-like material the determined characteristic relates to and / or which portion of the accumulation of elongated, string-like material (e.g., related to a particular set of nozzles, as discussed further below). Thus, characteristics of an individual, e.g., strand of material, such as a filament, produced can be determined, and / or characteristics of a particular portion of a filament produced by a particular set of nozzles can be determined. The determined characteristic(s) can be related to a dried final product obtained by drying the wet material. Additionally or alternatively, characteristics or conditions related to an individual nozzle and / or a particular set of nozzles and / or a particular nozzle within a set of nozzles that produced a particular accumulation of elongated, string-like material can be determined.

[0013] Via the imaging means and the acquired imaging data, several different types of properties can also be determined simultaneously, which properties may be indicative of the quality of the material produced by drying the moist material and / or may be indicative of the quality or functional parameters of the process for providing the (dried) produced material or for providing the moist material to be dried.

[0014] The control unit may be configured to facilitate an action related to adjusting at least one of providing the wet material or directing the wet material through the plurality of nozzles to the dry surface, optionally altering the determined characteristic in a selected manner.

[0015] At least one selected action may be performed based on the at least one determined characteristic, and the action may be an adjustment to a process for drying the moist material or providing the moist material to be dried, and there may be no requirement to stop the entire process to determine what adjustments need to be made and / or to make the adjustments.

[0016] In one embodiment, the apparatus may additionally comprise a mixing unit configured to receive at least one raw material component, optionally cellulose fibrils, and at least one solvent, optionally water, and a control unit configured to adjust mixing parameters, such as mixing speed, based on the determined characteristics.

[0017] Embodiments of the apparatus may include at least one drying unit configured to provide drying energy, such as heat, to dry the moist material.

[0018] In one embodiment, the control unit may be configured to determine at least one characteristic indicative of at least one dimension of at least one of the elongated strands of material. By obtaining information regarding the dimensions of the elongated strands of material, it may be possible to determine the uniformity of the material to be produced. The uniformity may relate to the quality of the material to be produced. If no material is being provided through a particular nozzle, the at least one dimension may be zero.

[0019] The characteristic indicating at least one dimension of the string-like material accumulation may imply the absence of a particular string-like material accumulation on the surface that should be present on the surface when the nozzle is provided at the corresponding location in the device. Thus, the dimension here may be a width determined to be zero or close to zero. This characteristic may be obtained, for example, by determining the number of elongated string-like material accumulations present on the surface at a particular location. This number may be compared to the number of elongated string-like material accumulations that should be present on the surface at that particular location if all nozzles are functioning as required. The characteristic of elongated string-like material accumulations for a clogged nozzle may be the absence of elongated string-like material accumulations.

[0020] The one or more characteristics may be determined based on imaging data relating to a separate accumulation of elongated, string-like material and / or based on imaging data relating to a set or portion of an accumulation of elongated, string-like material, for example, relating to a set of nozzles, as further discussed herein.

[0021] The dimensional characteristic may also provide data regarding the continuity of the string-like material accumulation(s).

[0022] Based on the one or more determined dimensions or one or more characteristics indicative of dimensions and / or uniformity of one or more of the elongated, thin, string-like accumulations of material, it may be determined that a dimension or uniformity for the selected elongated, thin, string-like accumulations of material exceeds a predetermined maximum value or is below a predetermined minimum value, and / or the characteristic indicative of at least one dimension is indicative of the absence of at least one elongated, thin, string-like accumulation. Thereafter, at least one performed action may include determining that a nozzle associated with the selected elongated, thin, string-like accumulation is at least partially blocked.

[0023] Upon determining that at least one nozzle is at least partially blocked, the control unit may be configured to facilitate an action including adjusting the mass flow rate or volumetric flow rate of the wet material provided to the plurality of nozzles via the material supply unit, preferably by reducing the mass flow rate or volumetric flow rate of the wet material by a selected amount based on data indicative of the at least partially blocked nozzles so as to reach or approach the reduced exit velocity of the material from the unblocked nozzles.

[0024] The material supply unit may in some embodiments of the present invention be configured to provide the wet material through at least one set of nozzles comprising a selected number of nozzles, the wet material being provided to the at least one set of selected number of nozzles at a selected mass flow rate or volume flow rate, and the control unit may: obtaining or determining a nominal exit velocity of the wet material from one nozzle of the at least one set of nozzles comprising a selected number of nozzles; determining a number of nozzles within the at least one set of a selected number of nozzles that are at least partially blocked based on the imaging data; The method may be configured to adjust the mass flow rate or volume flow rate of the wet material provided to the selected number of nozzles of the at least one set to reach or at least approach a reference exit velocity of the wet material from the remaining nozzles of the selected number of nozzles of the at least one set.

[0025] Considering a set of nozzles including a selected number of nozzles, if one nozzle of the set is at least partially blocked, string-like material accumulations associated with unblocked nozzles of the set may include dimensions greater than a threshold dimension and / or may exhibit enlarged dimensions, where adjustments made may optionally result in a reduction of these dimensions to a reference value, such as a reference width.

[0026] The imaging device may include at least one optical-mechanical imaging device configured to acquire at least one image, optionally at least one camera, such as a photographic camera, a line scan camera, and / or a video camera.

[0027] The imaging data can be efficiently used to determine which string-like material accumulations are affected and / or which particular nozzles are at least partially blocked or otherwise malfunctioning so that adjustments can be efficiently made to compensate for the malfunction so that the process can still continue, so that the determined parameters can be adjusted in a selected manner, and / or so that maintenance procedures can be efficiently facilitated for the particular nozzles requiring maintenance.

[0028] In some embodiments, the control unit may be configured to determine multiple different properties essentially simultaneously. One property may relate to the dimensions of the elongated strand-like material accumulation(s), for example, and one other determined property may be indicative of the quality of the produced material, such as a property related to a color parameter. Thus, for example, blockage of one or more nozzles may be detected essentially simultaneously with monitoring the quality of the produced material. Acquiring and analyzing imaging data may enable the simultaneous determination of multiple different types of properties.

[0029] The control unit may be configured to determine at least one quality parameter for the at least one accumulation of elongated strand-like material based on the at least one determined characteristic, and the at least one action may then include assigning at least one quality grade to at least a portion of the provided moisture-containing material to be dried according to predetermined criteria. Based on the quality indicator, a selected portion of the produced material may be vented or used for a different purpose than the produced material, e.g., having a different level of quality indicator.

[0030] The control unit may be configured to determine properties including, for example, color parameters of the wet material or uniformity parameters of the wet material, which may include parameters related to color intensity, which may be determined through color imaging data or black and white or grayscale imaging data.

[0031] There is also provided in accordance with one aspect of the present invention a method for providing a moist material to be dried, the method comprising: Providing a moisture-containing material; directing the wet material through a plurality of nozzles onto a drying surface and moving the drying surface relative to the plurality of nozzles to obtain a plurality of elongated strands of material; acquiring imaging data relating to a plurality of elongated string-like accumulations of material; determining at least one characteristic of at least one of the elongated string-like accumulations of material based on the imaging data; and performing at least one action based on the determined characteristic.

[0032] The novel features which are regarded as characteristic of the invention are set forth with particularity in the appended claims. However, the invention itself, both as to its organization and its method of operation, together with additional objects and advantages thereof, will best be understood from the following description of specific illustrative embodiments when read in connection with the accompanying drawings.

[0033] As will be appreciated by those skilled in the art, the considerations presented regarding various apparatus embodiments may be flexibly applied mutatis mutandis to the method embodiments, and vice versa.

[0034] The invention will now be explained in more detail with reference to exemplary embodiments according to the accompanying drawings, in which: [Brief explanation of the drawings]

[0035] [Figure 1] 1 illustrates a side view of at least a portion of an exemplary device. [Figure 2] 1 illustrates a top view of at least a portion of an exemplary device. [Figure 3] 1 illustrates a flow chart of a method. DETAILED DESCRIPTION OF THE INVENTION

[0036] Figure 1 schematically illustrates at least a portion of an apparatus for providing a wet material to be dried. The apparatus includes a material supply unit 102 configured to receive or provide the wet material and direct the wet material to a plurality of nozzles 104. Figure 1 depicts a side view of the apparatus from a first viewing direction that is essentially in the same plane as the machine direction X. From the side view of the example apparatus of Figure 1, only one nozzle 104 may be provided along the line of sight.

[0037] The nozzle 104 may be a material output configured to receive a wet material and provide the wet material through an orifice of a selected size. The size of the orifice and the dimensions of the nozzle 104 may depend on the feedstock and / or the material to be produced through the process. The nozzle may be, for example, a syringe-type nozzle having an orifice with an inner diameter in the micrometer range.

[0038] The apparatus additionally comprises at least one imaging device 110 or imaging means for acquiring imaging data, and at least one control unit 112 configured to acquire the imaging data and facilitate the performance of at least one action.

[0039] The apparatus may also include or be provided in association with one or more drying units 114 configured to provide drying energy, such as heat, to dry the moist material. Drying may refer to removing at least a portion, or essentially all, of the moisture in the moist material. The drying unit(s) 114 may be a device that provides a heated gas stream, or the drying unit may additionally or alternatively be located below the drying surface 106 and directly heat the drying surface, for example.

[0040] The apparatus may further include one or more mixing units 116. The mixing unit 116 may be configured to receive and mix together at least one raw material component and at least one solvent to provide the wet material. The mixing unit may be provided as a separate entity configured to direct the wet material to one or more material supply units 102, or the mixing unit 116 and material supply unit 102 may be provided as a single entity.

[0041] The mixing unit 116 may be associated with one or more mixing parameters. The mixing parameters may relate, for example, to the mixing speed or the composition of the wet material. The composition of the wet material may refer to which components are used in the material and / or in what order and / or amount the components are utilized. The composition parameters may relate, for example, to the viscosity of the wet material by being associated with the amount of rheology modifier that may be received by the mixing unit and mixed with at least one raw material and solvent.

[0042] At least one feedstock component may be provided in pulp form, e.g., may include at least cellulose fibrils, such as microfibrillated cellulose. Additionally or alternatively, the feedstock component may include, e.g., at least one protein fiber source.

[0043] The present invention is particularly advantageous in connection with processes for drying material comprising at least cellulose fibrils, where the elongated, strand-like accumulations of material are dried to form filaments that may be further processed, e.g., to form yarn. Naturally, the present invention may be usable with various types of material to be dried, provided as elongated, strand-like accumulations of material, and where the properties of the material and / or associated nozzle characteristics are to be determined or monitored.

[0044] The material supply unit 102 can be configured to control at least one parameter related to the manner in which the wet material is provided to the plurality of nozzles 104. The at least one parameter can include a mass flow rate of the wet material being provided. The mass flow rate can be the mass flow rate provided to a selected set of nozzles. The mass flow rate can be the same or different for different sets of nozzles.

[0045] The plurality of nozzles 104 are configured to receive the wet material and dispense the wet material therethrough to selected locations on the drying surface 106. The drying surface 106 (or at least a portion thereof) is configured to be movable relative to the plurality of nozzles 104. In the apparatus of FIG. 1 , the drying surface 106 (or at least selected locations on the drying surface 106) is configured to be movable along the machine direction X such that, as the wet material is dispensed onto the drying surface 106 through the nozzles 104, multiple elongated strands of material are formed. Thus, each elongated strand of material 108 may originate from and be associated with a particular nozzle 104.

[0046] The drying surface 106 may include a belt, such as a conveyor belt type element. Alternatively, the drying surface may include, for example, at least one rotating drum or cylinder.

[0047] At least one imaging device 110 of the apparatus is configured to acquire imaging data for at least one of the elongated, strand-like accumulations of material 108. Preferably, imaging data is acquired for a plurality of the elongated, strand-like accumulations of material 108 or for all of the elongated, strand-like accumulations of material 108.

[0048] The imaging device 110 may be any type of imaging device. For example, devices utilizing X-ray and / or magnetic resonance imaging techniques may be considered, although optical imaging devices may provide an economical and / or convenient means for acquiring imaging data. The imaging device 110 may be or include, for example, a camera, such as a digital photo camera, a (digital) video camera, or a line scan camera.

[0049] The type of imaging device 110 selected may be based on the type of imaging data desired and / or the type of characteristics to be determined based on the imaging data. The imaging data may be acquired through an imaging device that utilizes light of selected wavelengths, which may be in the visible and / or infrared spectrum, for example.

[0050] The apparatus may include only one imaging device 110, or the apparatus may include multiple imaging devices 110. The imaging devices 110 may be the same type of imaging device, or they may be different types of imaging devices 110, for example, where different types of characteristics are determined via different types of acquired imaging data.

[0051] Multiple imaging devices 110 may also be used to collectively obtain more or more useful imaging data; for example, multiple imaging devices 110 utilized for each selected area may result in higher resolution of the imaging data.

[0052] Multiple imaging devices 110 may be provided at selected imaging locations, for example, along the mechanical axis X. One or more properties may then be determined at different time intervals for the same elongated strand of material 108. For example, properties may be monitored as the moist material is dried while traversing the axis X.

[0053] One preferred selected imaging location for the at least one imaging device 110 may be close to the nozzle 104, for example, within 1 m in the X direction from the nozzle 104, so that the material output from the nozzle 104 can be effectively monitored.

[0054] One other selected imaging location for the at least one imaging device 110 may be near the end of the drying surface 106, which refers to the point where dried material should be removed from the drying surface 106. Note that the referenced drying surface location may refer to a location at a selected time. Thus, the "drying surface end point" may refer to a location on the drying surface 106 (or generally, an area along the drying surface in a direction perpendicular to direction X) positioned where material should be removed from the drying surface at a given time.

[0055] The control unit 112 may comprise at least one memory unit and one or more processing units for data processing. The control unit 112 may be a separate computing unit with a wired or wireless connection to at least one of the other components of the device, or the control unit may be integrated with one or more of the other device components.

[0056] The control unit 112 is configured to acquire imaging data and, based on the imaging data, determine at least one characteristic of at least one of the elongated, thin, string-like accumulations of material 108. The characteristic may be determined for and with respect to one or more elongated, thin, string-like accumulations of material 108 separately and / or the characteristic may be determined with respect to a plurality of elongated, thin, string-like accumulations of material 108 as a group or set.

[0057] A variety of different types of properties can be determined. Only one property can be determined, or multiple properties can be determined simultaneously. Properties can be directly derivable based on the imaging data, and / or properties that are directly derivable based on the imaging data can be used to determine (further) properties or characteristics of the material, including solvent content, of the dried material, and / or of equipment components or process parameters.

[0058] For example, based on the imaging data, the determined characteristic may relate to the uniformity of the at least one elongated strand-like accumulation of material 108 (e.g., based on brightness variations in the imaging data). The uniformity may be indicative of air bubbles present in the elongated strand-like accumulation of material 108. The characteristic or further property determined based on the uniformity may then be, for example, a quality parameter for the elongated strand-like accumulation of material 108. The quality parameter may indicate, for example, that the final (dried) product produced is of poor quality if air bubbles are determined to be present in a manner and / or amount above a threshold level.

[0059] The determined characteristic may be, for example, a dimensional parameter, a uniformity parameter, and / or a color parameter for the at least one elongated strand-like accumulation of material 108 .

[0060] The determined characteristic may be indicative of at least one dimension of at least one of the elongated string-like accumulations of material 108. Here, the characteristic may relate to the presence of a selected elongated string-like accumulation of material 108 at a particular location (imaged location) on the dry surface 106 at a particular (imaged) time, and / or the number of elongated string-like accumulations of material 108 present on the dry surface 106 at a particular location on the dry surface 106, and / or the continuity of at least one of the elongated string-like accumulations of material 108.

[0061] The characteristic indicative of at least one dimension of at least one of the elongated string-like material accumulations 108 may be, for example, the width of at least one of the elongated string-like material accumulations 108, which may be determined directly based on the imaging data.

[0062] If the associated nozzle is at least partially blocked, the width of the elongated strand-like material accumulation 108 may be below the threshold value. If at least one nozzle in a set of associated nozzles is at least partially blocked, thereby causing at least a portion of the nozzles in the set to output wet material at an undesirably high rate, the width of the elongated strand-like material accumulation 108 may exceed the threshold value.

[0063] A characteristic that may be considered may be indicative of the distance between the elongated strands of material 108. The characteristic may be utilized to determine that the nozzle 104 is not outputting the wet material in the desired location.

[0064] The characteristic indicative of at least one dimension of at least one of the elongated string-like material accumulations 108 may additionally or alternatively include data related to, for example, the number of elongated string-like material accumulations 108 present on the drying surface 106, e.g., along a cross-sectional axis that is essentially perpendicular to the machine axis X at the imaging location where the imaging data is acquired, and preferably includes information regarding the location of the current elongated string-like material accumulation 108 on the surface, from which it can be determined which particular nozzle 104 produced the current elongated string-like material accumulation 108. Thus, if the nozzles 104 are functioning as required, it may be possible to determine which particular nozzle 104 an absent elongated string-like material accumulation 108 is associated with, i.e., which location on the drying surface corresponds to where the elongated string-like material accumulation 108 should be. The characteristic or condition related to one or more nozzles 104 that can then be determined may indicate blockage or non-blockage (or the degree of blockage) of the nozzle 140. To determine such data, for example, a line-scan camera is sufficient. Thus, the use of a high-resolution, high-quality camera is not necessary.

[0065] The characteristic indicative of at least one dimension of at least one of the elongated string-like accumulations 108 may additionally or alternatively include data regarding the number of elongated string-like accumulations 108 present on the dry surface 106, which may be used to determine that at least one elongated string-like accumulation 108 is present where it should not be. This may be the case when the imaging device 110 is utilized at or near the end of the dry surface 106.

[0066] Based on the determined at least one characteristic, the control unit 112 is additionally configured to facilitate the implementation of at least one action, which may relate, for example, to the adjustment of the functionality of the material supply unit 102 and / or the mixing unit 116, to the assignment of one or more quality parameters and / or to the adjustment of the supply of material, including moisture.

[0067] In one embodiment, the adjustment may relate to the difference in speed between the supply of wet material and the speed of the moving drying surface 106. The adjustment may be an adjustment to the speed of movement of the drying surface 106.

[0068] The adjustment may relate to a mixing parameter based on, for example, a determined color parameter or a uniformity parameter determined based on at least one determined characteristic. In this case, the color or uniformity may then be adjusted as desired. For example, the mixing speed may be increased to obtain a more homogeneous material.

[0069] The action may involve adjusting the positioning of one or more of the apparatus components, such as adjusting the positioning of the nozzle head if the determined characteristic indicates, for example, that two elongated strands of material 108 are too close to one another. The adjustment may also be adjusting the distance between one or more nozzles 104 and the drying surface 106.

[0070] FIG. 2 shows a top view of at least a portion of an exemplary apparatus, in which a material supply unit 102 delivers a wet material to multiple sets 202 of nozzles 104. While individual nozzles 104 are not depicted in FIG. 2, the figure depicts an exemplary apparatus having three sets 202 of nozzles 104, with each set 202 containing five nozzles 104. The number of nozzle sets and the number of nozzles in each set are merely exemplary. The number of nozzle sets 202 can be, for example, from two to several tens of sets 202, and the number of nozzles 104 in each set 202 can be from a few nozzles 104 to several thousand nozzles 104, such as from 100 to 1,000 nozzles 104 per set 202.

[0071] Each nozzle 104 may be configured, at least when functioning properly as intended, to output a wet material to provide an elongated string-like accumulation 108 of material on the drying surface 106 .

[0072] 2 illustrates one imaging device 110 that is preferably configured to acquire imaging data for all of the strand-like material accumulations 108 provided (at least when the apparatus is functioning as intended). As explained above, any other number of imaging devices 110 may also be utilized at any selected imaging location. FIG. 2 also depicts an end or termination area / location 204 of the dry surface 106.

[0073] The exemplary apparatus of FIG. 2 includes two drying units 114 positioned above the drying surface 106, although of course a different number and / or type of drying units may also be utilized.

[0074] The determined characteristic may indicate, for example, that at least one set 202 of nozzles including a selected number of nozzles 104 outputs a number of elongated string-like material accumulations 108 that is less than the selected number of nozzles 104 included in the set 202 of nozzles. The number of blocked nozzles 104 may then be determined.

[0075] It may have been determined that a set 202 of nozzles 104 including a selected number of nozzles should have each nozzle 104 outputting the wet material at or near a reference or target exit velocity, and / or that when all nozzles 104 of the set 202 are unclogged, a selected mass flow rate of the wet material should be delivered to the set of nozzles via the material supply unit 102 at a reference or starting condition.

[0076] If the determined characteristic indicates that at least one of the nozzles 104 in the set of nozzles 202 is at least partially blocked, this will entail the unclogged nozzles 104 of the set of nozzles 202 outputting the wet material at an exit velocity that exceeds the reference or target exit velocity. The control unit 112 may be configured to determine an adjusted (reduced) mass flow rate of the wet material to be delivered to the set of nozzles 202 based on the number of blocked nozzles 104, such that the remaining unclogged nozzles 104 of the set of nozzles 202 output the wet material at an exit velocity that is adjusted to or near the reference or target exit velocity.

[0077] This may be followed by an action by the control unit 112 causing the material supply unit 102 to change the mass flow rate of the wet material to the particular set(s) 202 of nozzles that includes one or more blocked nozzles 104 from the previously provided mass flow rate to the adjusted mass flow rate. After this adjustment, the remaining unblocked nozzles 104 in the set 202 may output the wet material at or near the nominal or target exit velocity.

[0078] The action may alternatively or additionally include providing information to a user of the device indicating which particular nozzle 104 is at least partially blocked so that appropriate maintenance procedures can be facilitated.

[0079] 3 shows a flowchart of a method for providing a moist material to be dried. The method includes providing a moist material (302). Providing the moist material can be performed, for example, by mixing together at least one raw material component and at least one solvent.

[0080] The method further includes directing (304) the wet material through a plurality of nozzles 104 onto a drying surface 106 and moving the drying surface 106 relative to the plurality of nozzles 104 to obtain a plurality of elongated string-like accumulations of material 108.

[0081] At 306, the method includes acquiring imaging data relating to the plurality of elongated strand-like accumulations of material 108.

[0082] The method then includes determining 308 at least one characteristic of at least one of the elongated string-like accumulations of material based on the imaging data, wherein the at least one characteristic may be indicative of at least one dimension of the elongated string-like accumulations of material 108.

[0083] The method further includes performing (310) at least one action based on the determined characteristic.

[0084] The present invention has been described above with reference to the above-mentioned embodiments, and some advantages of the present invention have been demonstrated. It is clear that the present invention is not limited to these embodiments, but includes all possible embodiments within the spirit and scope of the present invention and the following claims.

[0085] The features recited in the corresponding claims are mutually freely combinable unless expressly stated otherwise.

Claims

1. 1. An apparatus for providing a moist material to be dried, said apparatus comprising at least: a material supply unit (102); a plurality of nozzles (104); a drying surface (106) configured to be movable relative to the plurality of nozzles; the material supply unit is configured to receive or provide a wet material and direct the wet material through the plurality of nozzles onto the drying surface to obtain a plurality of elongated strand-like material accumulations (108); The device, at least one imaging device (110) configured to acquire imaging data of at least one of the elongated strand-like accumulations of material; and at least one control unit (112) configured to determine at least one characteristic of at least one of the elongated string-like accumulations of material based on the imaging data, the control unit being additionally configured to facilitate performance of at least one action based on the determined characteristic.

2. 10. The apparatus of claim 1, wherein the apparatus additionally comprises a mixing unit (116) configured to receive at least one feedstock component, optionally cellulose fibrils, and at least one solvent, optionally water, and wherein the control unit is configured to adjust mixing parameters, such as a mixing speed, based on the determined characteristics.

3. 3. The apparatus of claim 1 or claim 2, wherein the apparatus comprises at least one drying unit (114) configured to provide drying energy, such as heat, to dry the moist material.

4. 4. The apparatus of claim 1, wherein the control unit is configured to facilitate an action relating to adjusting at least one of providing a wet material or directing the wet material through a plurality of nozzles to a dry surface, optionally to modify the determined characteristic in a selected manner.

5. 5. The apparatus of claim 1, wherein the control unit is configured to determine at least one characteristic indicative of at least one dimension of at least one of the elongated string-like accumulations of material, and optionally, the characteristic is utilized to determine the number of elongated string-like accumulations of material present on the surface.

6. 6. The apparatus of claim 5, wherein the control unit is configured to determine that a nozzle associated with at least one accumulation of elongated, string-like material is at least partially blocked if the control unit determines that at least one dimension of at least one accumulation of elongated, string-like material exceeds a predetermined maximum value or is below a predetermined minimum value, and / or if the characteristic indicative of the at least one dimension indicates the absence of at least one accumulation of elongated, string-like material.

7. 7. The apparatus of claim 6, wherein if at least one nozzle is determined to be at least partially blocked, the control unit is configured to facilitate an action including adjusting the mass flow rate or volumetric flow rate of the material, including moisture, provided to the plurality of nozzles via the material supply unit, preferably by reducing the mass flow rate or volumetric flow rate of the material, including moisture, by a selected amount based on data indicative of the nozzles being at least partially blocked so as to reach or approach a reduced exit velocity of the material from an unblocked nozzle.

8. The material supply unit is configured to provide the water-containing material through at least one set of nozzles including a selected number of nozzles, and the water-containing material is provided to the at least one set of selected number of nozzles at a selected mass flow rate or volume flow rate, and the control unit: obtaining or determining a nominal exit velocity of the wet material from one nozzle of the at least one set of nozzles comprising a selected number of nozzles; determining a number of nozzles within the at least one set of a selected number of nozzles that are at least partially blocked based on the imaging data; 8. The apparatus of claim 7, configured to adjust the mass flow rate or volumetric flow rate of the wet material provided to a selected number of the nozzles of the at least one set to reach or at least approach the reference exit velocity of the wet material from the remaining nozzles of the selected number of the nozzles of the at least one set.

9. 9. The apparatus of any one of claims 1 to 8, wherein the imaging device comprises at least one optical-mechanical imaging device configured to acquire at least one image, optionally at least one camera, such as a photographic camera, a line scan camera, and / or a video camera.

10. 10. The apparatus of claim 1, wherein the imaging device is configured to acquire a plurality of images, and the control unit is configured to essentially continuously monitor the at least one determined characteristic.

11. An apparatus according to any preceding claim, wherein the control unit is configured to determine a plurality of different characteristics essentially simultaneously.

12. 12. The apparatus of claim 1, wherein the control unit is configured to determine at least one quality parameter for the at least one elongated strand-like material accumulation based on the at least one determined characteristic, and wherein the at least one action comprises assigning at least one quality grade to at least a portion of the provided moisture-containing material to be dried according to predetermined criteria.

13. The apparatus of any one of claims 1 to 12, wherein the control unit is configured to determine a property comprising a color parameter of the material containing moisture or a uniformity parameter of the material containing moisture.

14. 1. A method for providing a moist material to be dried, said method comprising: Providing a wet material (302); directing the wet material through a plurality of nozzles onto a drying surface and moving the drying surface relative to the plurality of nozzles to obtain a plurality of elongated strands of material (304); acquiring (306) imaging data relating to the plurality of elongated strand-like accumulations of material; determining (308) at least one characteristic of at least one of the elongated strand-like accumulations of material based on the imaging data; and performing (310) at least one action based on the determined characteristic.

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