Particle size measuring device, method and program, and granulation device and method

Abstract

To provide a grain size measurement device, a grain size measurement method and a grain size measurement program with which it is possible to measure grain sizes with higher accuracy.SOLUTION: This grain size measurement device D comprises: an image acquisition unit 1 for acquiring an image in which a granular substance to be measured is imaged, and which is the object of measurement; a statistical feature quantity processing unit 22 for finding, from the image to be measured which was acquired by the image acquisition unit 1, a statistical feature quantity based on a relationship in pixel value between a first image and a second image within a prescribed range from the first pixel; a correspondence information storage unit 31 for storing correspondence information that represents a correspondence between the statistical feature quantity and a grain size; and a granularity processing unit 23 for finding, using correspondence information stored in the correspondence information storage unit 31, the grain size that corresponds to the statistical feature quantity obtained by the statistical feature quantity processing unit 22.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a particle size measuring apparatus, a particle size measuring method, and a particle size measuring program for measuring particle size, and a granulating apparatus and a granulating method for granulating particulate matter, which are provided with these.

Background Art

[0002] Measurement of particle size such as particle diameter (grain diameter) and particle diameter distribution (grain diameter distribution) is required in various fields that handle particulate raw materials and products, for example, for setting manufacturing conditions and quality evaluation. As an example, iron ore pellets, which are charged materials for blast furnaces, are manufactured by adding auxiliary materials and binders to powdered iron ore, which is a pellet raw material, as necessary, further adding a predetermined amount of moisture, granulating green pellets with a granulator, and drying and firing them. It is known that the particle size of green pellets varies due to fluctuations in granulation conditions such as the particle size, supply amount, and added moisture amount of the pellet raw material, and changes in the generation status of deposits in the granulator during the granulation stage of green pellets. On the other hand, charged materials for blast furnaces are required to have a uniform pellet diameter in order to ensure air permeability in the blast furnace. Therefore, the particle size of the green pellets granulated by the granulator is measured. This particle size measurement method is disclosed in, for example, Patent Document 1.

[0003] The method for measuring the average particle size of granules disclosed in this Patent Document 1 is a method for measuring the average particle size of deposited granules. Among the n-th moments Mn (n = 0, 1, 2, ···) of the power spectrum of an image obtained by photographing the deposited granules, the average particle size of the granules is obtained using at least one moment of a certain order. In one aspect, a particle extraction image is generated by binarizing or floating binarizing the image obtained by photographing the deposited granules, and the n-th moment Mn of the power spectrum of this particle extraction image is used. The floating binarization is performed by generating a blurred image by moving-averaging the image, generating an image obtained by subtracting the blurred image from the image, and binarizing the subtracted image.

Prior Art Documents

Patent Document

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] By the way, in the method for measuring the average particle size of the granular material disclosed in the above Patent Document 1, when fine particles alone and fine particles attached to or deposited on large particle size particles are mixed in the image, the power spectrum of the image treats them in the same way, resulting in a decrease in the accuracy of the particle size. Due to the threshold value used in the binarization or floating binarization, there are particle contours buried in noise within the same image, resulting in a decrease in the accuracy of the particle size. In the floating binarization, since the blurred image is subtracted from the image, fine particles are buried, resulting in a decrease in the accuracy of the particle size.

[0006] The present invention is an invention made in view of the above circumstances, and its object is to provide a particle size measuring device, a particle size measuring method, and a particle size measuring program capable of measuring the particle size with higher accuracy. And the present invention is to provide a granulating device equipped with the particle size measuring device and a granulating method equipped with the particle size measuring method.

Means for Solving the Problems

[0007] As a result of various studies, the present inventors have found that the above object is achieved by the following present invention. That is, a particle size measuring device according to an aspect of the present invention includes an image acquisition unit that acquires an image of a measurement target obtained by imaging a particulate matter to be measured, and from the image of the measurement target acquired by the image acquisition unit, a first pixel and a second pixel within a predetermined range with respect to the first pixel. A statistical feature quantity processing unit that obtains a statistical feature quantity based on the relationship between the pixel values of each pixel, a correspondence relationship information storage unit that stores correspondence relationship information representing the correspondence relationship between the statistical feature quantity and the particle size, and a particle size corresponding to the statistical feature quantity obtained by the statistical feature quantity processing unit. And a particle size processing unit that obtains the particle size using the correspondence relationship information stored in the correspondence relationship information storage unit. Preferably, in the above-described particle size measuring device, the particle size processing unit further obtains a particle size distribution (particle diameter distribution) in the image of the measurement target. Preferably, in the above-described particle size measuring device, the image acquisition unit is an imaging device that images the particulate matter to be measured and generates an image of the measurement target. Preferably, in the above-described particle size measuring device, the image acquisition unit is an interface circuit that inputs and outputs data to and from an external device, and the external device is a storage medium that stores an image of the measurement target. Preferably, in the above-described particle size measuring device, the image acquisition unit is an interface circuit that inputs and outputs data to and from an external device, and the external device is a drive device that reads data from a recording medium that records an image of the measurement target. Preferably, in the above-described particle size measuring device, the image acquisition unit is a communication interface circuit that transmits and receives communication signals to and from an external device, and the external device is connected to the communication interface circuit via a network and manages an image of the measurement target. It is a server device.

[0008] Such a particle size measuring device obtains a statistical feature quantity based on the relationship between the pixel values of the first and second pixels from the image of the measurement target, and converts this into a particle size (particle diameter), so that the particle size can be measured more accurately.

[0009] In another aspect, in the above-described particle size measuring apparatus, the statistical feature quantity processing unit divides the image of the measurement target into a plurality of regions, and obtains each statistical feature quantity for each of the plurality of regions. Preferably, in the above-described particle size measuring apparatus, the plurality of regions are each mesh obtained by dividing the image of the measurement target into a mesh shape.

[0010] Such a particle size measuring apparatus obtains the statistical feature quantity of the region and converts it into a particle diameter. Therefore, by adjusting the size (size, area) of the region, it is possible to select the particle diameter to be detected. As a result, when a single fine particulate matter and a fine particulate matter attached or laminated to a large-diameter particulate matter are mixed and appear in the image of the measurement target, the ratio of the single fine particulate matter can be measured more accurately.

[0011] In another aspect, in the above-described particle size measuring apparatus, the statistical feature quantity processing unit obtains a co-occurrence matrix in the image of the measurement target acquired by the image acquisition unit, and obtains a correlation value between rows and columns in the obtained co-occurrence matrix as the statistical feature quantity. Preferably, in the above-described particle size measuring apparatus, the co-occurrence matrix is a matrix representing the occurrence probability of adjacent pixel pairs in which the relationship between the first pixel value of the pixel (target pixel, reference pixel) and the second pixel value of the adjacent pixel adjacent to the pixel is the same for each pixel value. Preferably, in the above-described particle size measuring apparatus, the co-occurrence matrix is a matrix representing the occurrence probability of adjacent pixel pairs in which the relationship between the first pixel value of the pixel (target pixel, reference pixel) and the second pixel value of the adjacent pixel adjacent to the pixel on the right side in the row direction of the pixel is the same for each pixel value.

[0012] Such a particle size measuring apparatus can obtain a statistical feature quantity by simple information processing (simple arithmetic processing) by using a co-occurrence matrix.

[0013] In another aspect, in these above-described particle size measuring apparatuses, the predetermined range is a range adjacent to the first pixel. Preferably, in the above-described particle size measuring apparatus, the first and second pixels are two adjacent pixels. Preferably, in the above-described particle size measuring apparatus, the predetermined range is a range adjacent to the first pixel on one side (right side) or the other side (left side) in the horizontal direction (row direction) of the image. Preferably, in the above-described particle size measuring apparatus, the predetermined range is a range adjacent to the first pixel on one side (upper side) or the other side (lower side) in the vertical direction (column direction) of the image. Preferably, in the above-described particle size measuring apparatus, the predetermined range is a range including the first pixel in the first diagonal direction (upper right direction), the second diagonal direction (upper left direction), the third diagonal direction (lower right direction), or the fourth diagonal direction (lower left direction).

[0014] According to this, a particle size measuring apparatus can be provided in which the predetermined range is a range adjacent to the first pixel.

[0015] In another aspect, in these above-described particle size measuring apparatuses, an illumination unit for illuminating the particulate matter to be measured is further provided.

[0016] Such a particle size measuring apparatus is further provided with an illumination unit, so that the particle size can be measured under a certain illumination environment, and thus the variation in measurement accuracy can be reduced.

[0017] A particle size measuring method according to another aspect of the present invention includes an image acquisition step of acquiring an image of the measurement target obtained by imaging the particulate matter to be measured, a statistical feature amount processing step of obtaining a statistical feature amount based on the relationship between each pixel value in the first pixel and the second pixel within a predetermined range with respect to the first pixel from the image of the measurement target obtained in the image acquisition step, and a particle size processing step of obtaining a particle size corresponding to the statistical feature amount obtained in the statistical feature amount processing step using correspondence relationship information representing the correspondence relationship between the statistical feature amount and the particle size.

[0018] A particle size measurement program according to another aspect of the present invention causes a computer to execute an image acquisition step of acquiring an image of a particulate matter to be measured, which is an image of the particulate matter to be measured; a statistical feature amount processing step of obtaining a statistical feature amount based on the relationship between each pixel value at a first pixel and a second pixel within a predetermined range with respect to the first pixel from the image of the particulate matter to be measured obtained in the image acquisition step; and a particle size processing step of obtaining a particle size corresponding to the statistical feature amount obtained in the statistical feature amount processing step by using correspondence relationship information representing the correspondence relationship between the statistical feature amount and the particle size.

[0019] Such a particle size measurement method and particle size measurement program obtain a statistical feature amount based on the relationship between each pixel value at adjacent pixels from the image of the particulate matter to be measured, and convert this into a particle size (particle diameter), so that the particle size can be measured more accurately.

[0020] A granulating device according to another aspect of the present invention includes a granulating unit that granulates a particulate matter from a raw material under predetermined granulation conditions; any one of the above-described particle size measuring devices that determines the particle size of the particulate matter granulated in the granulating unit as the measurement target; and an adjustment unit that adjusts the predetermined granulation conditions based on the particle size of the particulate matter determined by the particle size measuring device.

[0021] According to this, a granulating device including any one of the above-described particle size measuring devices can be provided. Since the granulating device adjusts predetermined granulation conditions, it can granulate a particulate matter having a predetermined particle size as a target.

[0022] In another aspect, in the above-described granulating device, the particulate matter is a green pellet of an iron ore granulated product obtained by adding quicklime as a binder to powdered iron ore as the raw material and adding a predetermined amount of water. The adjustment unit adjusts at least one of the mixing ratio when the powdered iron ore contains a plurality of types, the addition amount of the quicklime, and the predetermined amount of the water.

[0023] Such a granulating device can granulate an iron ore granulated product having a predetermined particle size as a target.

[0024] Another aspect of the granulation method according to the present invention includes a granulation step of granulating particulate matter from raw materials under predetermined granulation conditions, a particle size measurement method of obtaining the particle size of the particulate matter as the measurement target from the particulate matter granulated in the granulation step, and an adjustment step of adjusting the predetermined granulation conditions based on the particle size of the particulate matter obtained by the particle size measurement method.

[0025] According to this, a granulation method equipped with the above-described particle size measurement method can be provided. Since the above granulation method adjusts predetermined granulation conditions, particulate matter with a predetermined particle size as a target can be granulated.

Effects of the Invention

[0026] The particle size measurement device, particle size measurement method, and particle size measurement program according to the present invention can measure the particle size more accurately. And according to the present invention, a granulation device equipped with the particle size measurement device and a granulation method equipped with the particle size measurement method can be provided.

Brief Description of the Drawings

[0027]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Figure 15

Figure 16

Embodiments for Carrying Out the Invention

[0028] Hereinafter, one or more embodiments of the present invention will be described with reference to the drawings. However, the scope of the invention is not limited to the disclosed embodiments. In each figure, components with the same reference numerals indicate the same components, and the description thereof will be omitted as appropriate. In this specification, when referring to components in general, reference numerals without subscripts are used, and when referring to individual components, reference numerals with subscripts are used.

[0029] The particle size measuring device in the embodiment is a device that measures the particle size such as the particle diameter (grain size) and the particle size distribution (grain size distribution) in the particulate matter to be measured. This particle size measuring device includes an image acquisition unit that acquires an image of the particulate matter to be measured, which is an image of the measurement target; a statistical feature quantity processing unit that obtains a statistical feature quantity based on the relationship between each pixel value at a first pixel and a second pixel within a predetermined range with respect to the first pixel from the image of the measurement target acquired by the image acquisition unit; a correspondence relationship information storage unit that stores correspondence relationship information representing the correspondence relationship between the statistical feature quantity and the particle diameter; and a particle size processing unit that obtains the particle diameter corresponding to the statistical feature quantity obtained by the statistical feature quantity processing unit using the correspondence relationship information stored in the correspondence relationship information storage unit. Hereinafter, such a particle size measuring device will be described using, as an example, an example applied to the granulation process in the production of iron ore pellets and sintered ore for blast furnaces. However, the particulate matter is not limited to iron ore pellets and granulated materials during the production of sintered ore, and may be any substance (for example, raw materials, products, etc.) as long as it is granular (particulate).

[0030] FIG. 1 is a block diagram showing the configuration of the particle size measuring apparatus according to the first embodiment. FIG. 2 is a diagram for explaining a case where the particle size measuring apparatus is used in a granulation process as an example. FIG. 2A is a schematic diagram showing the whole, and FIG. 2B is a schematic diagram showing the vicinity of the image acquisition unit. FIG. 3 is a diagram for explaining the calculation method of the gray level co-occurrence matrix for the first row. FIGS. 3A and 3C show the pixel values of the image, and FIGS. 3B and 3C show the co-occurrence matrix. FIG. 4 is a diagram for explaining the calculation method of the gray level co-occurrence matrix for the first row. FIGS. 4A and 4C show the pixel values of the image, and FIGS. 4B and 4C show the co-occurrence matrix. FIG. 5 is a diagram for explaining the calculation method of the gray level co-occurrence matrix for the second to sixth rows. FIGS. 5A and 5C show the pixel values of the image, and FIGS. 5B and 5C show the co-occurrence matrix. FIG. 6 is a diagram for explaining the gray level co-occurrence matrix of the calculation result as an example. FIG. 6A shows the pixel values of the image, FIG. 6B shows the co-occurrence matrix, and FIG. 6C shows the heat map of the co-occurrence matrix. FIG. 7 is a diagram for explaining the gray level co-occurrence matrix of the calculation result as another example. FIG. 7A shows the pixel values of the image, FIG. 7B shows the co-occurrence matrix, and FIG. 7C shows the heat map of the co-occurrence matrix. FIG. 8 is a diagram for explaining the correlation value between the row and the column in the co-occurrence matrix for the image of the measurement target. FIG. 8A shows the correlation value, and FIGS. 8B to 8E show the respective sample images of sample image numbers 1 to 4. The horizontal axis of FIG. 8A is the sample image number, and the vertical axis thereof is the correlation value (COR). FIG. 9 is a diagram for explaining the calculation method of the statistical feature amount. FIG. 9A shows the image, FIG. 9B shows the statistical feature amount for each region, and FIG. 9C shows the histogram of each statistical feature amount.

[0031] In the first embodiment, the particle size measuring apparatus D includes, for example, as shown in FIG. 1, an image acquisition unit 1, a control processing unit 2, a storage unit 3, an input unit 4, an output unit 5, and an interface unit (IF) 6.

[0032] The image acquisition unit 1 is a device that is connected to the control processing unit 2 and acquires an image of the measurement target obtained by imaging the particulate matter to be measured according to the control of the control processing unit 2. The image acquisition unit 1 is, for example, an imaging device that images the particulate matter to be measured and generates an image of the measurement target. The imaging device is, for example, a color digital camera, a monochrome digital camera, or the like. Alternatively, the image acquisition unit 1 is, for example, an interface circuit that inputs and outputs data to and from an external device. The external device is a storage medium such as a USB (Universal Serial Bus) memory and an SD card (registered trademark) that stores the image of the measurement target. Alternatively, the external device is a drive device that reads data from a recording medium such as a CD-ROM (Compact Disc Read Only Memory), a CD-R (Compact Disc Recordable), a DVD-ROM (Digital Versatile Disc Read Only Memory), and a DVD-R (Digital Versatile Disc Recordable) that records the image of the measurement target. The interface circuit as the image acquisition unit 1 may be connected to the external device by wire or wirelessly. Alternatively, the image acquisition unit 1 is, for example, a communication interface circuit that transmits and receives communication signals to and from an external device, and the external device is connected to the communication interface circuit via a network (WAN (Wide Area Network, including a public communication network)) or a LAN (Local Area Network), and is a server device that manages the image of the measurement target. Note that when the image acquisition unit 1 is an interface circuit or a communication interface circuit, the image acquisition unit 1 may be used in combination with the IF unit 6 (that is, the IF unit 6 may be used as the image acquisition unit 1).

[0033] In the present embodiment, the particle size measuring device D is used, for example, in the granulation process of a blast furnace, and in order to measure the particle size of iron ore pellets in substantially real time, the image acquisition unit 1 is a color digital camera (hereinafter abbreviated as "camera") 1. Note that the image acquisition unit 1 may be a monochrome digital camera.

[0034] In the granulation process of the iron ore pellets for this blast furnace, for example, as shown in Fig. 2A, two pan granulators P-1 and P-2 are provided in parallel as granulators. Granulation raw materials in which fine ore is mixed with auxiliary raw materials such as limestone and binders such as bentonite as required and a predetermined amount of water is further added are supplied to each of the granulators P-1 and P-2, and by rotating each of the granulators P-1 and P-2 at a predetermined inclination angle and rotation speed, the granulation raw materials are granulated into pellets. The green pellets (granulated pellets) Ob discharged from each of the granulators P-1 and P-2 are carried out by the conveying conveyors B-1 and B-2 respectively, then merged on the collecting conveyor B-3, and after being screened to a predetermined particle size range via a vibration screen (not shown) from this conveyor B-3, they are conveyed to a firing furnace (not shown) such as a grate kiln for drying and firing.

[0035] In a plant that implements such a granulation process, the image acquisition unit 1 of the particle size measuring device D is provided with cameras 1a (1a-1, 1a-2) arranged to image, for example, granulation pellets (an example of particulate matter) Ob conveyed on the conveying conveyors B-1 and B-2 from above, more specifically, directly from above as shown in FIGS. 2A and 2B. In the example shown in FIG. 2, the image acquisition unit 1 includes not only the camera 1a but also a pair of lighting devices 1b (1b-1, 1b-2) and 1c (1c-1, c-2) juxtaposed via the camera 1a along a direction orthogonal to the conveying direction of the conveying conveyors B-1 and B-2 in order to illuminate the granulation pellets Ob obliquely from above. By intentionally illuminating the granulation pellets Ob with a brightness that causes a change in luminance according to the presence or absence of the granulation pellets Ob on the conveying conveyor B by the pair of lighting devices 1b and 1c from the left and right of the camera 1a, a change in luminance in the granulation pellets Ob to be measured can appear stably. Therefore, since the particle size measuring device D can measure the particle size under such a constant illumination environment, variations in measurement accuracy can be reduced. The set (assembly) of the camera 1a and the pair of lighting devices 1b and 1c as the image acquisition unit 1 has two (two sets) corresponding to the two conveying conveyors B-1 and B-2. The first set of the camera 1a-1 and the pair of lighting devices 1b-1 and 1c-1 is arranged for the conveying conveyor B-1, and the second set of the camera 1a-2 and the pair of lighting devices 1b-2 and 1c-2 is arranged for the conveying conveyor B-2. Since the set of the camera 1a and the pair of lighting devices 1b and 1c is arranged in the same manner with respect to the conveying conveyor B, in FIG. 2B, the first set of the camera 1a-1 and the pair of lighting devices 1b-1 and 1c-1 arranged for the conveying conveyor B-1 is mainly shown, and the second set of the camera 1a-2 and the pair of lighting devices 1b-2 and 1c-2 arranged for the conveying conveyor B-2 is shown by enclosing the reference numerals of the camera 1a-2 and the pair of lighting devices 1b-2 and 1c-2 in parentheses after the reference numerals of the corresponding camera 1a-1 and the pair of lighting devices 1b-1 and 1c-1.

[0036] The input unit 4 is connected to the control processing unit 2, and is a device that inputs various commands such as a command for instructing the start of measurement of the particle size of the measurement target by, for example, a particle size measuring device D, and various data necessary for operating the particle size measuring device D such as, for example, the date of measurement, etc. For example, it is a plurality of input switches, a keyboard, a mouse, etc. to which a predetermined function is assigned. The output unit 5 is connected to the control processing unit 2, and is a device that outputs the commands and data input from the input unit 4 and the particle size measured by the particle size measuring device D according to the control of the control processing unit 2. For example, it is a display device such as a CRT display, an LCD (liquid crystal display device), and an organic EL display, a printing device such as a printer, etc.

[0037] Note that the input unit 4 and the output unit 5 may be constituted by a touch panel. In the case of constituting this touch panel, the input unit 4 is a position input device that detects and inputs an operation position such as a resistive film method or a capacitance method, and the output unit 5 is a display device. In this touch panel, the position input device is provided on the display surface of the display device, one or a plurality of input content candidates that can be input to the display device are displayed, and when the user touches the display position where the input content to be input is displayed, the position is detected by the position input device, and the display content displayed at the detected position is input to the particle size measuring device D as the user's operation input content. In such a touch panel, since the user can easily understand the input operation intuitively, a particle size measuring device D that is easy for the user to handle is provided.

[0038] The IF unit 6 is connected to the control processing unit 2, and is a circuit that inputs and outputs data, for example, between the control processing unit 2 and an external device. For example, it is an interface circuit of RS-232C using a serial communication method, an interface circuit using the Bluetooth (registered trademark) standard, and an interface circuit using the USB standard, etc. Further, the IF unit 6 may be a communication interface circuit that transmits and receives communication signals to and from an external device, such as a data communication card or a communication interface circuit according to the IEEE802.11 standard, etc.

[0039] The memory unit 3 is a circuit connected to the control processing unit 2 and stores various predetermined programs and various predetermined data according to the control of the control processing unit 2. The various predetermined programs include, for example, a control program for controlling each part 1, 3 to 6 of the particle size measuring device D, a statistical feature quantity processing program for obtaining a statistical feature quantity based on the relationship between each pixel value between the first pixel and the second pixel within a predetermined range with respect to the first pixel from the image of the measurement object acquired by the image acquisition unit 1, and a particle size processing program for obtaining the particle size corresponding to the statistical feature quantity obtained by the statistical feature quantity processing program using the correspondence relationship information stored in the correspondence relationship information storage unit 31 described later, and other control processing programs. The various predetermined data include data necessary for executing these programs, such as the image of the measurement object acquired by the image acquisition unit 1 and the correspondence relationship information. Such a memory unit 3 includes, for example, a ROM (Read Only Memory) which is a non-volatile memory element, an EEPROM (Electrically Erasable Programmable Read Only Memory) which is a rewritable non-volatile memory element, and the like. And the memory unit 3 includes a RAM (Random Access Memory) and the like which serve as a working memory of the so-called control processing unit 2 for storing data and the like generated during the execution of the predetermined program. Further, the memory unit 3 may be configured to include a hard disk device with a relatively large storage capacity.

[0040] And the memory unit 3 functionally includes a correspondence relationship information storage unit 31 for storing the correspondence relationship information. The correspondence relationship information is information representing the correspondence relationship between the statistical feature quantity and the particle size of the particulate matter. More specifically, the correspondence relationship information uses the correlation value between rows and columns in the co-occurrence matrix of the image of the measurement object as the statistical feature quantity, and is information representing the correspondence relationship between the correlation value and the particle size of the particulate matter. The correspondence relationship information is, for example, created in advance from a plurality of samples and stored in the correspondence relationship information storage unit 31. The correlation value functions as an index for evaluating the particle size of the particulate matter Ob.

[0041] The control processing unit 2 is a circuit that controls each part 1, 3 to 6 of the particle size measuring device D according to the functions of the respective parts to measure the particle size of the particulate matter to be measured. The control processing unit 2 is configured to include, for example, a CPU (Central Processing Unit) and its peripheral circuits. When the control processing program is executed, the control processing unit 2 functionally includes a control unit 21, a statistical feature quantity processing unit 22, and a particle size processing unit 23.

[0042] The control unit 21 controls each part 1, 3 to 6 of the particle size measuring device D according to the functions of the respective parts, and is in charge of the overall control of the particle size measuring device D.

[0043] The statistical feature quantity processing unit 22 obtains a statistical feature quantity based on the relationship between each pixel value between the first pixel and the second pixel within a predetermined range with respect to the first pixel from the image of the measurement target acquired by the image acquisition unit 1. More specifically, the statistical feature quantity processing unit 22 obtains a co-occurrence matrix in the image of the measurement target acquired by the image acquisition unit, and obtains the correlation value between the row and the column in the obtained co-occurrence matrix as the statistical feature quantity.

[0044] The particle size processing unit 23 obtains the particle size corresponding to the statistical feature quantity obtained by the statistical feature quantity processing unit 22 by using the correspondence information stored in the correspondence information storage unit 31. In the present embodiment, the particle size processing unit 23 further obtains the particle size distribution (particle diameter distribution) in the image of the measurement target. The particle size distribution (particle diameter distribution) is a histogram representing the number of particles for each particle size in the plurality of particles captured in the image of the measurement target. More specifically, the particle size processing unit 23 obtains the particle size corresponding to the correlation value obtained by the statistical feature quantity processing unit 22 by using the correspondence information stored in the correspondence information storage unit 31, obtains the appearance frequency for each class of particle size, and obtains the histogram of particle size, thereby obtaining the particle size distribution (particle diameter distribution) in the image of the measurement target. Alternatively, the particle size processing unit 23 obtains the appearance frequency for each class of correlation value with respect to the correlation value obtained by the statistical feature quantity processing unit 22, obtains the histogram of the correlation value, converts the class of the correlation value into the particle size by using the correspondence information stored in the correspondence information storage unit 31, and obtains the particle size distribution in the image of the measurement target.

[0045] Here, the statistical feature amount and the relationship between this statistical feature amount and the particle size will be described. When illuminating the particulate matter Ob so as to generate a shadow of the particulate matter Ob with a brightness that causes a change in brightness according to the presence or absence of the particulate matter Ob, in an image obtained by converting a color image into, for example, a 256 - gradation grayscale image (an image in which the RGB pixel values are converted into luminance values by a known conversion formula), the pixel value of the pixel in which the particulate matter Ob is reflected becomes a pixel value close to the brightest luminance value 255, while the pixel value of the pixel in which the shadow is reflected becomes the darkest black luminance value 0. For this reason, as the particle size of the particulate matter Ob becomes smaller, the frequency (probability) of the alternate appearance of the pixels with the black luminance value 0 due to the shadow and the pixels with a luminance value close to the luminance value 255 irradiated on the particulate matter Ob increases. Therefore, for a certain pixel of interest (the pixel of interest), when the probability of the appearance of a pixel having a luminance value similar to the luminance value of the pixel of interest in the neighborhood is high, it can be estimated that the particle size of the particulate matter Ob is large. On the other hand, when the probability of the appearance of a pixel having a luminance value different from the luminance value of the pixel of interest in the neighborhood is high, it can be estimated that the particle size of the particulate matter Ob is small. Thus, for example, the particle size of the particulate matter Ob can be estimated from the probability distribution of the luminance values that appear in the neighboring pixels for a pixel having a certain luminance value (0 - 255). For this reason, the statistical feature amount is a quantity (value) based on the relationship between the first pixel and the pixel values between the first pixel and the second pixel within a predetermined range with respect to the first pixel. For example, in the image to be measured, it is the difference between the pixel values of neighboring pixels, the ratio of the pixel values of neighboring pixels, the similarity based on the difference or the ratio, the dissimilarity based on the difference or the ratio, the periodicity of the difference or the ratio, or the probability distribution of the difference or the ratio, etc. The predetermined range is appropriately set from a plurality of samples within the range where the statistical feature amount and the particle size of the particulate matter Ob are correlated. For example, the predetermined range is a range adjacent to the first pixel. That is, the first and second pixels are two adjacent pixels. In one example, the predetermined range is a range adjacent to the first pixel on one side (right side) or the other side (left side) in the horizontal direction (row direction) of the image. The minimum distance between the first and second pixels is one pixel, and the maximum distance is the number of pixels corresponding to the maximum diameter within the particle when viewing the minimum particle size of the particle size to be measured on the two - dimensional image.In another example, the predetermined range is a range adjacent to the first pixel on one side (upper side) or the other side (lower side) in the vertical direction (column direction) of the image. In another example, the predetermined range is a range including the first pixel in a first diagonal direction (upper right direction), a second diagonal direction (upper left direction), a third diagonal direction (lower right direction), or a fourth diagonal direction (lower left direction).

[0046] As an example, such statistical feature amounts can be obtained by a Gray Level Cooccurence Matrix (GLCM) filter that extracts information regarding the texture (spatial distribution pattern of pixel values) of an image when the statistical feature amounts are probability distributions of luminance values between adjacent pixels. This GLCM filter calculates the frequency (probability) of occurrence of a pair of specific cell values at positions adjacent to each position of a filter window (for example, a cell located adjacent on the right, a cell located adjacent above, or cells adjacent in all directions). That is, the GLCM filter is a matrix (co-occurrence matrix) having as elements the probability Pδ(α, β) that the density at a point (for example, a pixel) displaced by a displacement δ (distance r, direction θ) from a point of density α (luminance value in one example) in the image is β.

[0047] More specifically, for example, in FIGS. 3 to 6, in the case of a 256 - tone image, the GLCM is a matrix with 256 rows and 256 columns, and each element has a value from 0 to 1. The values of each row represent the pixel values (in this example, luminance values from 0 to 255) of the target pixel (reference pixel), and each column represents the pixel values (in this example, luminance values from 0 to 255) of the pixel adjacent to the target pixel, for example, the pixel adjacent to the right in the row direction (adjacent pixel). For example, in the case of a 6×6 image with smoothly changing pixel values (in this example, luminance values from 0 to 255) shown in FIGS. 3A and 3C, etc., the frequency (total number) of the pair where the pixel value of the target pixel is 0 and the pixel value of the adjacent pixel is 0 does not exist in the image shown in FIG. 3A, etc., and is 0. Therefore, as shown in FIG. 3B, the element in the first row and first column of the GLCM represented by frequency (frequency GLCM) is 0. The frequency (total number) of the pair where the pixel value of the target pixel is 0 and the pixel value of the adjacent pixel is 1 exists as 1 in the image shown in FIG. 3A, etc., as shown in FIG. 3C. Therefore, as shown in FIG. 3D, the element in the first row and second column of the frequency GLCM is 1. The frequency (total number) of the pair where the pixel value of the target pixel is 0 and the pixel value of the adjacent pixel is 2 does not exist in the image shown in FIG. 3A, etc., and is 0, as shown in FIG. 4A. Therefore, as shown in FIG. 4B, the element in the first row and third column of the frequency GLCM is 0. Similarly, hereinafter, the frequency (total number) of the pair where the pixel value of the target pixel is 0 and the pixel value of the adjacent pixel is k becomes the element in the first row and k + 1 column of the frequency GLCM (k = 0 to 255), and as shown in FIG. 4D, each element in the first row of the frequency GLCM is obtained. The frequency (total number) of the pair where the pixel value of the target pixel is 1 and the pixel value of the adjacent pixel is k becomes the element in the second row and k + 1 column of the frequency GLCM, and as shown in FIG. 5B, each element in the second row of the frequency GLCM is obtained. For example, the frequency (total number) of the pair where the pixel value of the target pixel is 1 and the pixel value of the adjacent pixel is 2 exists as 2 in the image shown in FIG. 3A, etc., as shown in FIG. 5A. Therefore, as shown in FIG. 5B, the element in the second row and third column of the frequency GLCM is 2. Similarly, hereinafter, when each element of the frequency GLCM is obtained up to the sixth row, it becomes as shown in FIG. 5D. For example, the frequency (total number) of the pair where the pixel value of the target pixel is 4 and the pixel value of the adjacent pixel is 5 exists as 5 in the image shown in FIG. 3A, etc., as shown in FIG. 5C. Therefore, as shown in FIG. 5D, the element in the fifth row and sixth column of the frequency GLCM is 5.In this way, the frequency (total number) of pairs where the pixel value of the target pixel is m and the pixel value of the adjacent pixel is n becomes the element at the (m + 1)-th row and (n + 1)-th column of the frequency GLCM (m = 0 to 255, n = 0 to 255). The frequency GLCM of the images shown in FIGS. 3A and 6A, etc. is as shown in FIG. 6B, and its heat map is as shown in FIG. 6C. And the GLCM is obtained by dividing each element of the frequency GLCM by the total number of pixels in the image to obtain the probability of each element. The total number of pixels in the image is when the image has a size of M rows and N columns (total number of pixels M×N), and when the neighboring pixel is K pixels away from the target pixel. As in the above example, when the neighboring pixel is adjacent to the target pixel in the row direction (left - right direction) of the target pixel, the total number of pixels is M×(N - K), or when the neighboring pixel is adjacent to the target pixel in the column direction (up - down direction) of the target pixel, the total number of pixels is (M - K)×N, or when the neighboring pixel is adjacent to the target pixel in the diagonal direction, the total number of pixels is (M - K)×(N - K).

[0048] In this way, in the examples shown in FIGS. 3 to 6, the co - occurrence matrix represents, for each pixel value, the occurrence probability of adjacent pixel pairs where the relationship between the first pixel value of the pixel (target pixel, reference pixel) and the second pixel value of the adjacent pixel adjacent to the right in the row direction of the pixel is the same.

[0049] Also, in the case of a 6×6 image having pixel values (in this example, luminance values from 0 to 255) that change smoothly while including noise as shown in FIG. 7A, its frequency GLCM is as shown in FIG. 7B, and its heat map is as shown in FIG. 7C.

[0050] If the co-occurrence matrix for the image to be measured is obtained, the particle size can be estimated based on the probability distribution. In this embodiment, the correlation value of the pixel values (luminance values in this example) of the neighboring pixels with respect to the target pixel is obtained by normalizing it within the range of -1 to +1. More specifically, from the co-occurrence matrix for the image to be measured obtained as described above, the correlation value COR between the row and the column in the co-occurrence matrix is obtained as the statistical feature amount by the following Equation 1. Here, i is the luminance value of the target pixel, j is the luminance value of the neighboring pixel, and Pσ(i, j) is the value (occurrence probability) of the element in the i-th row and j-th column in the co-occurrence matrix.

[0051] [Number]

[0052] As shown in FIG. 8A, this correlation value becomes +1 in the uniform image of sample image number 1 shown in FIG. 8B, and has a profile approaching -1 as the frequency of change in luminance values between adjacent pixels increases, as in each of the images of sample image numbers 2 to 4 shown in FIGS. 8C to 8E.

[0053] In this embodiment, since each particle size in the plurality of particulate substances Ob captured in the image to be measured is rarely uniform, the statistical feature amount processing unit 22 divides the image PC to be measured into a plurality of regions AR (AR11 to AR45), for example, as shown in FIG. 9A, and obtains each statistical feature amount for each of the plurality of regions AR, as shown in FIG. 9B. In FIG. 9B, the numerical values described within the □ in each region AR are the correlation values as the statistical feature amounts. In the example shown in FIG. 9A, the image PC is divided into 20 regions AR11 to AR15, AR21 to AR25, AR31 to AR35, and AR41 to AR45 of 4×5. In this example, the plurality of regions AR are each mesh of a rectangle obtained by dividing the image PC to be measured in a mesh (grid) shape. Note that the shape of the mesh is not limited to a rectangle, and may be other shapes such as a regular hexagon in order to divide it in a honeycomb-like manner. It is preferable to set the size of the region AR to the maximum value within the particle size range to be detected.

[0054] For example, as shown in FIG. 9C, the particle size processing unit 23 obtains the frequency of occurrence for each class of the correlation value with respect to the correlation value COR obtained by the statistical feature quantity processing unit 22, obtains a histogram of the correlation value, converts the class of the correlation value into a particle size using the correspondence relationship information stored in the correspondence relationship information storage unit 31, and obtains the particle size distribution in the image of the measurement target. In the example shown in FIG. 9C, there are five classes: 0 to 0.1 (0 or more and less than 0.1), 0.2 to 0.3 (0.2 or more and less than 0.3), 0.3 to 0.4 (0.3 or more and less than 0.4), 0.4 to 0.5 (0.4 or more and less than 0.5), and 0.5 to 1 (0.5 or more and 1 or less).

[0055] These control processing unit 2, storage unit 3, input unit 4, output unit 5, and IF unit 6 can be configured by, for example, a computer such as a desktop type or a notebook type. The computers constituting these units 2 to 6 are, for example, arranged in an operation room in a granulation process plant, may be incorporated into a console (may be used in combination with the console), or may be separate from the console.

[0056] Next, the operation of this embodiment will be described. FIG. 10 is a flowchart showing the operation of the particle size measuring device. FIG. 11 is a diagram showing the correlation between the actual measurement result and the measurement result of the particle size measuring device. The horizontal axis in FIG. 11 is the actual powder ratio by the sieve expressed in mass%, and the vertical axis is the powder ratio obtained by the particle size measuring device D expressed in mass%. FIG. 12 is a diagram for explaining the measurement result of a specific example by the particle size measuring device. FIG. 12A shows an example of an image of the measurement target, and FIG. 12B shows the particle size obtained by the particle size measuring device D for the image shown in FIG. 12A.

[0057] When the power of the particle size measuring device D having such a configuration is turned on, it initializes each necessary unit and starts its operation. In the control processing unit 2, the control unit 21, the statistical feature quantity processing unit 22, and the particle size processing unit 23 are functionally configured by executing the control processing program.

[0058] In FIG. 10, first, the particle size measuring device D acquires an image of the measurement target by the image acquisition unit 1 and stores the acquired image in the storage unit 3 (S1).

[0059] Next, the particle size measuring device D divides the image into a plurality of regions by the statistical feature amount processing unit 22 of the control processing unit 2 (S2). The size of the region is appropriately set in advance and stored in the storage unit 3 via the input unit 4. As described above, the size of the region is set to the maximum value among the particle size ranges to be detected.

[0060] Next, the particle size measuring device D obtains statistical feature amounts for each region by the statistical feature amount processing unit 22 (S3). In the present embodiment, a correlation value COR is obtained as the statistical feature amount for each region.

[0061] Next, the particle size measuring device D obtains a particle size for each region by the particle size processing unit 23 of the control processing unit 2 (S4).

[0062] Next, the particle size measuring device D obtains a particle size distribution (particle diameter distribution) in the image of the measurement target by the particle size processing unit 23 of the control processing unit 2 (S5).

[0063] Note that instead of the processes S4 and S5, the particle size processing unit 23 may obtain the frequency of appearance for each class of the correlation value COR obtained by the statistical feature amount processing unit 22 to obtain a histogram of the correlation value, and convert the class of the correlation value into a particle size using the correspondence information stored in the correspondence information storage unit 31 to obtain the particle size distribution in the image of the measurement target.

[0064] Next, the particle size measuring device D outputs the particle size obtained in the process S4 and the particle size distribution obtained in the process S5 to the output unit 5 by the control processing unit 2 (S6), and ends this process. Note that, if necessary, the particle size and the particle size distribution may be output from the IF unit 6 to an external device.

[0065] Note that in the granulation process, each of the processes S1 to S6 may be repeatedly executed at a predetermined time interval.

[0066] An example of the correlation between the powder ratio [% by mass] of particulate matter obtained by such a particle size measuring device D and the powder ratio [% by mass] of particulate matter actually measured by a sieve is shown in FIG. 11. As shown in FIG. 11, the powder ratio [% by mass] of particulate matter obtained by the particle size measuring device D correlates with the powder ratio [% by mass] of particulate matter actually measured by a sieve. From FIG. 11, it is understood that the particle size measuring device D in the present embodiment can accurately measure the particle size and the particle size distribution.

[0067] An example of the particle size obtained by the particle size measuring device D is shown in FIG. 12B for each of a plurality of regions. FIG. 12B shows the particle size obtained by the particle size measuring device D for the image shown in FIG. 12A. By comparing FIG. 12B with FIG. 12A, it is understood that the particle size measuring device D in the present embodiment can accurately measure the particle size.

[0068] As described above, the particle size measuring device D in the first embodiment, as well as the particle size measuring method and the particle size measuring program implemented thereon, obtain statistical features based on the relationship between each pixel value in the first and second pixels from an image of a measurement target, and convert this into a particle size (particle diameter). Therefore, the particle size can be measured more accurately, and thus the particle size distribution (particle diameter distribution) can be obtained more accurately. Compared with the method of measuring the particle size only by frequency analysis using the power spectrum, the particle size measuring device D, the particle size measuring method, and the particle size measuring program can measure the particle size more robustly when the brightness of the entire image changes or when the illuminance changes smoothly within the image.

[0069] Since the above particle size measuring device D, particle size measuring method, and particle size measuring program obtain the statistical feature amount of the region and convert it into the particle diameter, it is possible to select the particle diameter to be detected by adjusting the size (size, area) of the region. As a result, when a single fine particulate matter and fine particulate matter attached to or laminated on a large-diameter particulate matter are mixed and appear in the image of the measurement target, the ratio of the single fine particulate matter can be measured more accurately. Since the above particle size measuring device D, particle size measuring method, and particle size measuring program obtain the statistical feature amount of the region and convert it into the particle diameter, it is also possible to specify the positions where each particulate matter of small particle diameter and large particle diameter exists, simultaneously with the particle diameter distribution of the entire image.

[0070] The above particle size measuring device D, particle size measuring method, and particle size measuring program can obtain the statistical feature amount by simple information processing (simple arithmetic processing) by using the co-occurrence matrix.

[0071] Since the above particle size measuring device D, particle size measuring method, and particle size measuring program illuminate, the particle size can be measured under a certain illumination environment, so that the variation in measurement accuracy can be reduced.

[0072] Next, another embodiment (second embodiment) will be described. The second embodiment is an embodiment in which the above particle diameter measuring device is applied when adjusting the granulation conditions in the granulation system.

[0073] FIG. 13 is a schematic diagram showing the configuration of the granulation system in the second embodiment. FIG. 14 is a schematic view of the drum mixer in the granulation device of the granulation system. FIG. 14A is a perspective view seen from the side, and FIG. 14B is a longitudinal sectional view. FIG. 15 is a block diagram showing the electrical configuration of the granulation control device in the granulation system.

[0074] The granulation system S in the second embodiment is a system that granulates particulate matter from raw materials and dries and sinters the granulated particulate matter after granulation. In this embodiment, as an example, the particulate matter is an iron ore granulated product obtained by adding quicklime as a binder to powdered iron ore as the raw material and adding a predetermined amount of moisture for granulation, and the granulated product becomes the sintered ore by being dried and sintered. A predetermined auxiliary raw material is added to the raw material as necessary. Such a granulation system S includes, for example, as shown in FIGS. 13 to 15, a storage tank SR, a loading conveyor BC-1, a granulator DM, an unloading conveyor BC-2, a feeding hopper HP, a sintering machine (firing furnace) BK, a conveyor 9 (9-1 to 9-3), and a granulation control device A.

[0075] The storage tank SR is a tank (container) for storing materials for producing sintered ore such as raw materials and binders, and has, for example, a number corresponding to the type of the material. In the example shown in FIG. 13, it includes a first storage tank SR-1 for storing the first type of powdered iron ore, a second storage tank SR-2 for storing the second type of powdered iron ore different from the first type, and a third storage tank SR-3 for storing quicklime as a binder. The powdered iron ore is the raw material for the sintered ore, and generally has different properties depending on the production area (brand). For example, there are porous powdered iron ore and powdered iron ore with a smooth surface. The porous powdered iron ore requires a relatively large amount of moisture for granulation, while the powdered iron ore with a smooth surface can be granulated with a relatively small amount of moisture. Also, since the particles of the powdered iron ore adhere to each other due to the surface tension of water, the larger the amount of moisture, the easier it is for the particle size to become larger. In the production of granulated products for sintered ore, the amount of water added during granulation is related to the particle size of the granulated product Ob depending on the mixing ratio of the powdered iron ore (each occupancy rate (mass%) for each type relative to the whole) and the amount of moisture contained in the powdered iron ore before granulation. Note that since granulation proceeds with quicklime as a binder, the addition amount of the quicklime is also related to the particle size of the granulated product Ob. Since quicklime contains a large amount of fine particles, it is easy to fill the gaps between the particles of the powdered iron ore. Therefore, the larger the addition amount of quicklime, the less powder peels off from the granulated product, and the easier it is for the particle size to become larger.

[0076] The conveyor BC-1 for loading is, for example, a belt conveyor that conveys the material discharged from the storage tank SR to the granulator DM. In the present embodiment, the material stored in the storage tank SR is dropped and discharged from the storage tank SR into the sub-conveyor (not shown in FIG. 13, see FIG. 15) 9 (9-1 to 9-3), and by this sub-conveyor, the material discharged from the storage tank SR is conveyed to the main conveyor BC-1 for loading. Since the amount of the material discharged from the storage tank SR per unit time is substantially constant, by adjusting the conveying speed of the sub-conveyor 9, the amount of the material conveyed to the granulator DM via the conveyor BC-1 for loading is adjusted. In the example shown in FIGS. 13 to 15, a sub-first conveyor (not shown in FIG. 13, see FIG. 15) 9-1 is disposed in the first storage tank SR-1, and by this sub-first conveyor 9-1, the first type of powdered iron ore discharged from the first storage tank SR-1 is conveyed to the conveyor BC-1 for loading, and by adjusting the conveying speed of the sub-first conveyor 9-1, the amount of the first type of powdered iron ore conveyed to the granulator DM is adjusted. A sub-second conveyor (not shown in FIG. 13, see FIG. 15) 9-2 is disposed in the second storage tank SR-2, and by this sub-second conveyor 9-2, the second type of powdered iron ore discharged from the second storage tank SR-2 is conveyed to the conveyor BC-1 for loading, and by adjusting the conveying speed of the sub-second conveyor 9-2, the amount of the second type of powdered iron ore conveyed to the granulator DM is adjusted. By adjusting the amount of the first type of powdered iron ore and the amount of the second type of powdered iron ore, that is, the conveying speed of the sub-first conveyor 9-1 and the conveying speed of the sub-second conveyor 9-2, the mixing ratio of the powdered iron ore is adjusted. A sub-third conveyor (not shown in FIG. 13, see FIG. 15) 9-3 is disposed in the third storage tank SR-3, and by this sub-third conveyor 9-3, the quicklime discharged from the third storage tank SR-3 is conveyed to the conveyor BC-1 for loading, and by adjusting the conveying speed of the sub-third conveyor 9-3, the amount of the quicklime (the addition amount of the quicklime) conveyed to the granulator DM is adjusted.

[0077] The granulator DM is a device that granulates particulate matter from the materials in the storage tank SR carried in via the loading conveyor BC-1 under predetermined granulation conditions, for example, a drum mixer DM. In the example shown in FIG. 13, the granulator DM adds quicklime as a binder to the raw materials of the first and second powdered iron ores, adds a predetermined amount of water, and granulates the granulated product. The drum mixer DM includes, for example, as shown in FIG. 14, a cylindrical drum body DB inclined so as to descend from one longitudinal end to the other end. From the one end of the drum body DB, the materials in the storage tank SR (in this example, each material of the first and second powdered iron ores and quicklime) carried in via the loading conveyor BC-1 are introduced into the drum body DB. Inside the drum body DB, a water spray nozzle SN for spraying water is arranged at a position at a predetermined distance from the one end of the drum body DB and at the center inside the drum body DB. A water supply pipe (water conduit) WP for supplying (conducting water) water to the water spray nozzle SN is connected to the water spray nozzle SN. An adjustment valve 8 such as a solenoid valve is interposed in the water supply pipe WP to adjust the amount of water supplied to the water spray nozzle SN. By adjusting the opening degree of the adjustment valve 8, the flow rate flowing through the water supply pipe WP is adjusted, and the amount of water supplied to the water spray nozzle SN is adjusted. Thereby, the amount of water added to the materials in the drum body DB is adjusted. On the inner wall of the drum body DB, four rod-shaped (columnar) first to fourth lifter bars LB-1 to LB-4 are arranged in parallel with each other along the longitudinal direction of the drum body DB at equal intervals in the circumferential direction. The drum body DB rotates in a predetermined one direction by a rotation drive mechanism (not shown). When the drum body DB rotates, the materials in the drum body DB are sequentially caught by the first to fourth lifter bars LB-1 to LB-4 and lifted along with the rotation of the drum body DB, and then fall by gravity. Thereby, in the region (mixing region) from the one end of the drum body DB until the water sprayed by the water spray nozzle SN falls, the respective materials in the drum body DB are mixed, and in the region (water-added granulation region) where the water sprayed by the water spray nozzle SN falls, water-added granulation is performed. After the water sprayed by the water spray nozzle SN no longer falls, in the region (non-water-added rolling region) from the water spray nozzle SN to the other end of the drum body DB, rolling granulation is performed without adding water.The granulated product Ob granulated by the granulator DM is discharged from the other end of the drum body DB.

[0078] The conveying conveyor CB-2 is, for example, a belt conveyor that conveys the granulated product Ob discharged from the granulator DM to the ore feeding hopper HP.

[0079] The ore feeding hopper HP is a device that temporarily stores the granulated product Ob to be charged into the sintering machine (firing furnace) BK, and the granulated product Ob is charged from the ore feeding hopper HP into the sintering machine BK.

[0080] The sintering machine (firing furnace) BK is a device that dries and sinters the granulated product Ob charged from the ore feeding hopper HP to produce sintered ore. This sintering machine BK ignites from above the laminate in which the charged granulated product Ob is stacked in layers, and combustion is transmitted by sucking air at the lower part thereof. As a result, the granulated product Ob charged into the sintering machine BK is dried and sintered to become sintered ore.

[0081] As described above, since the sintering machine BK dries and sinters the granulated product Ob, gaps for air circulation are required in the laminate. Usually, granulated products Ob not exceeding 2 mm deteriorate the air permeability and reduce the productivity of sintered ore. For this reason, in order to avoid the generation of granulated product Ob that deteriorates the air permeability in the sintering machine BK, in the present embodiment, the granulation control device A provided in the granulation system S includes the above-described particle size measuring device D.

[0082] More specifically, as shown in FIG. 15, the granulation control device A includes an image acquisition unit 1 including a camera 1a and lighting devices 1b and 1c, a control processing unit 2a, a storage unit 3a, an input unit 4a, an output unit 5a, an IF unit 6a, a moisture meter 7, a regulating valve 8, and the above-described first to third conveyors 9-1 to 9-3.

[0083] The image acquisition unit 1 including this camera 1a and lighting devices 1b and 1c is the same as the image acquisition unit 1 in the particle size measurement device D in the first embodiment, and thus its description is omitted. Here, the camera 1a and the lighting devices 1b and 1c are arranged between the outlet side of the granulator DM and the inlet side of the ore feeder hopper HP in the granulation system S in order to continuously measure the particle size of the granulated material Ob. In the example shown in FIG. 13, in order to measure the granulated material Ob in the state discharged from the granulator DM, it is arranged at a position near the granulator DM so as to image the granulated material Ob conveyed on the carry-out conveyor BC-2 from directly above.

[0084] Note that in order to keep the distance between the granulated material Ob and the camera 1a substantially constant and to make the height of the granulated material deposited on the carry-out conveyor BC-2 constant, a so-called leveling plate may be further provided to level the top of the granulated material deposited on the carry-out conveyor BC-2. Further, since steam generated from the granulated material Ob due to the heat of hydration of quicklime may obstruct the field of view of the camera 1a, a so-called air purge for blowing off the steam may be provided.

[0085] The input unit 4a is the same as the input unit 4 in the particle size measurement device D in the first embodiment, except that commands and data related to granulation control are further input, and thus its description is omitted. The output unit 5a is the same as the output unit 5 in the particle size measurement device D in the first embodiment, except that commands and data related to granulation control are further output, and thus its description is omitted. The IF unit 6a is the same as the IF unit 6 in the particle size measurement device D in the first embodiment, except that data related to granulation control is further input and output between the external device and the IF unit 6a, and thus its description is omitted.

[0086] The moisture meter 7 is a device that is connected to the control processing unit 2a and measures the moisture content of the granulated product Ob according to the control of the control processing unit 2a, and the measurement result is output to the control processing unit 2a. The moisture meter 7 is, for example, an infrared moisture meter that irradiates the measurement target with near-infrared rays and measures the moisture content based on the reflection amount. The correspondence relationship between the reflection amount and the moisture content is obtained and stored as a so-called calibration curve. This infrared moisture meter is a measuring instrument that utilizes the fact that the absorption rate of specific wavelengths (for example, 1.45 μm, 1.94 μm, etc.) in the near-infrared region varies according to the water content in the substance. The moisture meter 7 is arranged close to the camera 1a.

[0087] The control valve 8 is a device that is connected to the control processing unit 2a and adjusts the flow rate flowing through the water supply pipe WP by adjusting its opening degree according to the control of the control processing unit 2a as described above. As a result, the amount of water supplied to the watering nozzle SN is adjusted, and the amount of water added to the material in the drum body DB is adjusted.

[0088] The first to third conveyors 9-1 to 9-3 are each connected to the control processing unit 2a and adjust the respective amounts of the respective materials carried into the granulator DM by adjusting their conveyance speeds according to the control of the control processing unit 2a as described above.

[0089] The storage unit 3a is the same as the storage unit 3 in the particle size measuring device D in the first embodiment, except that it further stores programs and data related to granulation control. That is, in the control processing program, in addition to the control program, the statistical feature amount processing program, the particle size processing program, etc., an adjustment program for adjusting the predetermined granulation conditions based on the particle size of the particulate matter (granulated product in this example) obtained by the particle size processing program is included. The various predetermined data include data necessary for executing these programs, such as the image of the measurement target acquired by the image acquisition unit 1 and the correspondence relationship information, as well as the target value of granulation control.

[0090] The control processing unit 2a controls each part 1, 3a to 6a, 7, 8, 9-1 to 9-3 of the granulation control device A according to the functions of the respective parts, measures the particle size of the granulated product Ob to be measured, and is a circuit for granulation control. The control processing unit 2a is configured to include, for example, a CPU and its peripheral circuits. When the control processing program is executed, the control processing unit 2a functionally includes a control unit 21a, a statistical feature amount processing unit 22, a particle size processing unit 23, and an adjustment unit 24. Since these statistical feature amount processing unit 22 and particle size processing unit 23 are the same as the statistical feature amount processing unit 22 and particle size processing unit 23 in the particle size measuring device D in the first embodiment, the description thereof is omitted.

[0091] The control unit 21a controls each part 1, 3a to 6a, 7, 8, 9-1 to 9-3 of the granulation control device A according to the functions of the respective parts, and is in charge of the overall control of the granulation control device A.

[0092] The adjustment unit 24 adjusts predetermined granulation conditions based on the particle diameter of the granulated product Ob obtained by the particle size processing unit 23. As described above, the particle diameter of the granulated product Ob is affected by the mixing ratio of the powdered iron ore, the addition amount of quicklime, and a predetermined amount of moisture, respectively. Therefore, each of these can be granulation conditions for granulating the granulated product Ob to a target particle diameter. For this reason, in the present embodiment, the adjustment unit 24 adjusts at least one of the mixing ratio when the powdered iron ore contains a plurality of types, the addition amount of quicklime, and the predetermined amount of moisture.

[0093] As described above, generally, the granulated product Ob that does not exceed 2 mm deteriorates the air permeability in the sintering machine BK and reduces the productivity of the sintered ore. Therefore, the granulation control device A aims to control the production amount of the granulated product Ob that does not exceed 2 mm (that is, the production amount of the granulated product Ob with a particle size of 2 mm or less). The target value of the granulation control is set based on the production amount of the granulated product Ob that does not exceed 2 mm, and is, for example, a predetermined range (target range) defined by its upper limit value and lower limit value. For this reason, more specifically, the adjustment unit 24 adjusts at least one of the mixing ratio in the case where the powdered iron ore contains a plurality of types, the addition amount of quicklime, and the predetermined amount of moisture so that the production amount of the granulated product Ob that does not exceed 2 mm is within the target range based on the particle size of the granulated product Ob obtained by the particle size processing unit 23. Note that the lower limit value may be set to 0, and the target range may be set only by the upper limit value.

[0094] Here, the particles with a particle size of 2 mm or less are defined as "powder", and the content rate of "powder" in the measurement object (the ratio of powder to the entire measurement object) is defined as the "powder rate". In this definition, more specifically, the adjustment unit 24 adjusts at least one of the mixing ratio in the case where the powdered iron ore contains a plurality of types, the addition amount of quicklime, and the predetermined amount of moisture so that the powder rate % of the granulated product Ob is within the target range (for example, 10% to 30%, or 30% or less, etc.) based on the particle size of the granulated product Ob obtained by the particle size processing unit 23.

[0095] These control processing unit 2a, storage unit 3a, input unit 4a, output unit 5a, and IF unit 6a can be configured by, for example, a computer such as a desktop type or a notebook type. The computers constituting these units 2a to 6a are, for example, arranged in the operation room in the granulation system S and may be incorporated into the console (may be used in combination with the console), or may be separate from the console.

[0096] In the present embodiment, the loading conveyor BC-1, the granulator DM, and the unloading conveyor BC-2 correspond to an example of the granulation unit, and the granulation control device A including the particle size measuring device D, the loading conveyor BC-1, the granulator DM, and the unloading conveyor BC-2 correspond to an example of the granulation apparatus.

[0097] Next, the operation of the present embodiment will be described. FIG. 16 is a flowchart showing the operation of the granulation control device related to the adjustment of granulation conditions.

[0098] When the granulation system S is operated and the granulation control device A including the particle size measuring device D is powered on, it initializes each necessary part and starts its operation. The control processing unit 2a is functionally configured with a control unit 21a, a statistical feature amount processing unit 22, a particle size processing unit 23, and an adjustment unit 24 by executing its control processing program.

[0099] The granulation control device A repeatedly executes each process shown in FIG. 16 at a preset predetermined time interval (for example, 0.5-hour interval, 1-hour interval, 2-hour interval, etc.) with respect to the adjustment of granulation conditions.

[0100] In FIG. 16, the granulation control device A measures the powder ratio of the granulated product Ob (S11). More specifically, the granulation control device A operates in the same manner as the particle size measuring device D in the first embodiment, generates an image of the granulated product Ob with the camera 1a, divides the image into a plurality of regions, obtains statistical feature amounts for each region, obtains the particle size for each region, and obtains the particle size distribution (particle diameter distribution) in the image of the measurement target. Then, the granulation control device A obtains the powder ratio from the obtained particle size distribution by the adjustment unit 24 of the control processing unit 2a. For example, the ratio of the sum of the frequencies of each class of 2 mm or less to the sum of the frequencies of each class in the particle size distribution (= ((sum of the frequencies of each class of 2 mm or less) / (sum of the frequencies of each class in the particle size distribution)) × 100) is obtained as the powder ratio [%]. Alternatively, for example, the powder ratio may be obtained in terms of area %, for example. The powder ratio in terms of area % is the percentage of the area of the powdered granulated product Ob with respect to the total area of the granulated product Ob captured in the image (= (total area of the powdered granulated product Ob) / (total area of the granulated product Ob captured in the image) × 100). The area is represented by, for example, the number of pixels. Alternatively, for example, the actual area included in one pixel is obtained in advance for each pixel position, and the area is represented by the actual area. Note that during a preset predetermined time (for example, 1 minute or 2 minutes, etc.), it may be repeated at a preset predetermined sampling interval (for example, 5 seconds or 10 seconds, etc.), the particle size distribution at each sampling timing is obtained and each powder ratio is obtained, and the average value of these powder ratios is used as the powder ratio (final powder ratio) of the processing result of process S11.

[0101] Next, the granulation control device A determines whether the powder ratio obtained in process S11 is within the target range by means of the adjustment unit 24 (S12). As a result of this determination, if the powder ratio obtained in process S11 is within the target range, that is, if the powder ratio obtained in process S11 is greater than or equal to the lower limit value of the target range and less than or equal to the upper limit value of the target range (YES, OK), the granulation control device A ends this process and ends the process at the current adjustment timing. On the other hand, as a result of the determination, if the powder ratio obtained in process S11 exceeds the target range, that is, if the powder ratio obtained in process S11 is less than the lower limit value of the target range, or if the powder ratio obtained in process S11 is greater than the upper limit value of the target range (NO, NG), the granulation control device A then executes process S13.

[0102] In this process S13, the granulation control device A selects, by means of the adjustment unit 24, a target for adjusting the granulation conditions. In the present embodiment, the adjustment unit 24 selects any one of the water content, the addition amount of quicklime, and the mixing ratio of fine ore. The selection is made according to a preset rule. For example, from the perspective of cost, the water content, the addition amount of quicklime, and the mixing ratio of fine ore are selected in this order. In this case, first, the water content is selected, and then the granulation control device A executes process S14-1. For example, within the adjustable range of the water content, when the particle size cannot be adjusted (that is, when the particle size cannot be adjusted even if the water content is set to 0 and when the particle size cannot be adjusted even if the water content is set to the maximum amount), or when further water addition is not possible with respect to the water content of the granulated product measured by the water meter 7, etc., the addition amount of quicklime is selected, and the granulation control device A then executes process S14-2. The maximum amount of the water content may be defined by the maximum flow rate of the water supply pipe WP, but since it is necessary to compensate for the amount of firing heat corresponding to the increase in the heat of evaporation due to the increase in the water amount with the sintering machine BK, it may also be defined taking into account the amount of firing heat. For example, within the adjustable range of the addition amount of quicklime, when the particle size cannot be adjusted (that is, when the particle size cannot be adjusted even if the addition amount of quicklime is set to the minimum amount required as a binder and when the particle size cannot be adjusted even if the addition amount of quicklime is set to the maximum amount), or when the addition amount of quicklime cannot be changed with respect to the storage amount (remaining amount) of quicklime stored in the third storage tank SR-3, etc., the mixing ratio of fine ore is selected, and the granulation control device A then executes process S14-3.

[0103] In the process S14-1, the granulation control device A controls the opening degree of the regulating valve 8 by the regulating unit 24 to adjust the amount of water sprayed by the water spray nozzle SN, ends this process, and ends the process at the current adjustment timing. For example, when the powder ratio obtained in the process S11 is lower than the lower limit value of the target range, in order to increase the powder ratio (in order to increase the granulated product Ob with a small particle size), the regulating unit 24 reduces the amount of water sprayed from the water spray nozzle SN by a preset predetermined amount (the first predetermined amount), and controls the opening degree of the regulating valve 8. Alternatively, for example, when the powder ratio obtained in the process S11 exceeds the upper limit value of the target range, in order to decrease the powder ratio (in order to increase the granulated product Ob with a large particle size), the regulating unit 24 increases the amount of water sprayed from the water spray nozzle SN by a preset predetermined amount (the second predetermined amount), and controls the opening degree of the regulating valve 8. The first predetermined amount and the second predetermined amount may be the same value or different values.

[0104] In the process S14-2, the granulation control device A controls the conveying speed of the third conveyor 9-3 by the regulating unit 24 to adjust the addition amount of quicklime, ends this process, and ends the process at the current adjustment timing. For example, when the powder ratio obtained in the process S11 is lower than the lower limit value of the target range, in order to increase the powder ratio (in order to increase the granulated product Ob with a small particle size), the regulating unit 24 reduces the addition amount of quicklime by a preset predetermined amount (the third predetermined amount), and controls the conveying speed of the third conveyor 9-3. Alternatively, for example, when the powder ratio obtained in the process S11 exceeds the upper limit value of the target range, in order to decrease the powder ratio (in order to increase the granulated product Ob with a large particle size), the regulating unit 24 increases the addition amount of quicklime by a preset predetermined amount (the fourth predetermined amount), and controls the conveying speed of the third conveyor 9-3. The third predetermined amount and the fourth predetermined amount may be the same value or different values.

[0105] In the said process S14-3, the granulation control device A adjusts the mixing ratio of the powdered iron ore by controlling the conveyance speeds of the first and second conveyors 9-1 and 9-2 by means of the adjustment unit 24, ends this process, and ends the process at the current adjustment timing. Since the ease of particle size increase (or decrease) varies depending on the type of powdered iron ore, an algorithm for adjusting the mixing ratio of the powdered iron ore is preset according to the type of powdered iron ore. For example, when the powder ratio obtained in process S11 is lower than the lower limit value of the target range, in order to increase the powder ratio, the adjustment unit 24 controls the conveyance speeds of the first and second conveyors 9-1 and 9-2 so as to adjust the mixing ratio of the powdered iron ore by a preset predetermined amount (fifth predetermined amount) according to the algorithm. Alternatively, for example, when the powder ratio obtained in process S11 exceeds the upper limit value of the target range, in order to decrease the powder ratio, the adjustment unit 24 controls the conveyance speeds of the first and second conveyors 9-1 and 9-2 so as to adjust the mixing ratio of the powdered iron ore by a preset predetermined amount (sixth predetermined amount) according to the algorithm. The fifth predetermined amount and the sixth predetermined amount may be the same value or different values.

[0106] As described above, each of these processes is repeatedly executed at a preset predetermined time interval. Therefore, if any one of processes S14-1 to S14-3 was executed at the previous adjustment timing, then process S12 at the current adjustment timing is also a process for confirming its effect. That is, as a result of the determination in process S12 at the current adjustment timing, if the powder ratio obtained in process S11 is within the target range (YES, OK), it is confirmed that the effect of the previous adjustment was achieved, and this process at the current adjustment timing ends. On the other hand, as a result of the determination in process S12 at the current adjustment timing, if the powder ratio obtained in process S11 exceeds the target range (NO, NG), it is confirmed that the effect of the previous adjustment was not achieved, or that the effect of the previous adjustment was achieved but was insufficient, and at the current adjustment timing as well, any one of processes S14-1 to S14-3 is executed. That is, the adjustment of the granulation conditions is continued. Also, even when the adjustment of the granulation conditions is stopped, if as a result of the determination in process S12 at any subsequent adjustment timing, the powder ratio obtained in process S11 exceeds the target range (NO, NG), the adjustment of the granulation conditions is restarted. Therefore, the granulation control device A can continuously and continuously control so that the powder ratio is within the target range while the granulation system S is operating.

[0107] Note that in the above description, the adjustment unit 24 selects any one of processes S14-1 to S14-3 to adjust the granulation conditions. However, when the powder ratio obtained in process S11 exceeds the target range (NO, NG), the adjustment unit 24 outputs, from the output unit 5a, an alarm prompting the user (operator) to select any one of processes S14-1 to S14-3, receives the user's selection of any one of processes S14-1 to S14-3 by the input unit 4a, and may execute any one of processes S14-1 to S14-3 according to the received selection. Furthermore, processes S14-1 to S14-3 may be automated within a system that performs granulation control with similar processes instead of being selected by the user.

[0108] Also, in the above description, the adjustment unit 24 selects any one of processes S14-1 to S14-3, but the adjustment unit 24 may select and execute a plurality of processes among processes S14-1 to S14-3.

[0109] Also, in the above description, when the adjustment unit 24 executes any one of processes S14-1 to S14-3, the effect confirmation is performed at the next adjustment timing. However, after the execution of any one of processes S14-1 to S14-3, a process for confirming the effect may be further provided. In this case, as a result of this effect confirmation, if the effect is present, this process (adjustment of granulation conditions in this case) is terminated. If the effect is not present or if the effect is present but insufficient, the process is returned to process S13. This effect confirmation is executed a predetermined number of times in advance so as to be within the predetermined time interval of the repetition of processes S11 to S14 (S14-1 to S14-3).

[0110] As described above, according to the second embodiment, a granulation control device A including the particle size measuring device D and a granulation method implemented thereon can be provided. The granulation system S, the granulation control device A, and the granulation method implemented thereon in the second embodiment adjust predetermined granulation conditions, so that particulate matter having a predetermined particle size as a target can be granulated.

[0111] The above granulation system S, granulation control device A, and granulation method implemented thereon can granulate an iron ore granulated product Ob having a predetermined particle size as a target.

[0112] In the example shown in FIG. 2B described above, a pair of lighting devices 1b and 1c are used for one camera 1a. However, the number of lighting devices is not limited to two and may be arbitrary. For example, four first to fourth lighting devices (such as LED lights, etc.) may be used for one camera 1a. These first to fourth lighting units are arranged so as to surround the camera 1a from all sides and illuminate the granulated product (an example of the particulate matter to be measured) Ob on the conveying conveyors B-1 and B-2 and the discharging conveyor BC-2. More specifically, when a square is virtually set on a virtual plane parallel to the conveying surface of the conveyor, the camera 1a is arranged such that its optical axis passes through the center (the intersection of the two diagonals) of the square, and the first to fourth lighting devices are arranged one at each of the four corners (the four corners) of the square such that their optical axes intersect the conveying surface. By illuminating from all sides, the shadow due to the unevenness of the granulated product Ob disappears, and imaging can be performed under the same conditions, so that the measurement is stabilized. Further, a light-shielding member (such as a dark curtain, etc.) may be used which is provided so as to cover such a lighting device and shields light from the outside. An observation window may be provided in the light-shielding member as necessary, and the camera 1a images the granulated product Ob through the observation window. In the second embodiment, the moisture meter 7 also measures the moisture content of the granulated product Ob through the observation window. The light-shielding member prevents so-called stray light, and the lighting environment is further stabilized.

[0113] In order to represent the present invention, the present invention has been appropriately and fully described through embodiments with reference to the drawings above. However, it should be recognized that those skilled in the art can easily make changes and / or improvements to the above-described embodiments. Therefore, unless the changes or improvements implemented by those skilled in the art deviate from the scope of the claims described in the claims, such changes or improvements are construed as being included within the scope of the claims of the claims.

Explanation of Reference Numerals

[0114] D Particle size measuring device A Granulation control device S Granulation system 1 Image acquisition unit 1a Camera 1b, 1c Lighting device 2, 2a Control processing unit 3, 3a Memory unit 21, 21a Control unit 22 Statistical feature quantity processing unit 23 Granularity processing unit 24 Adjustment unit 31 Corresponding relationship information memory unit

Claims

1. An image acquisition unit that acquires an image of the measurement target obtained by imaging the particulate matter to be measured; A statistical feature quantity processing unit that obtains a statistical feature quantity based on the relationship between each pixel value at a first pixel and a second pixel within a predetermined range with respect to the first pixel in the image of the measurement target acquired by the image acquisition unit; A correspondence relationship information storage unit that stores correspondence relationship information representing the correspondence relationship between the statistical feature quantity and the particle size; A particle size processing unit that obtains a particle size corresponding to the statistical feature quantity obtained by the statistical feature quantity processing unit by using the correspondence relationship information stored in the correspondence relationship information storage unit, and The statistical feature quantity processing unit obtains a co-occurrence matrix in the image of the measurement target acquired by the image acquisition unit, and obtains a correlation value between a row and a column in the obtained co-occurrence matrix as the statistical feature quantity. A particle size measuring device.

2. The statistical feature quantity processing unit divides the image of the measurement target into a plurality of regions, and obtains each statistical feature quantity for each of the plurality of regions. The particle size measuring device according to claim 1.

3. The predetermined range is a range adjacent to the first pixel. The particle size measuring device according to claim 1 or claim 2.

4. Further comprising an illumination unit that illuminates the particulate matter to be measured. The particle size measuring device according to any one of claims 1 to 3.

5. An image acquisition step of acquiring an image of the measurement target obtained by imaging the particulate matter to be measured; A statistical feature quantity processing step of obtaining a statistical feature quantity based on the relationship between each pixel value at a first pixel and a second pixel within a predetermined range with respect to the first pixel in the image of the measurement target acquired in the image acquisition step; A particle size processing step of obtaining a particle size corresponding to the statistical feature quantity obtained in the statistical feature quantity processing step by using correspondence relationship information representing the correspondence relationship between the statistical feature quantity and the particle size, and In the statistical feature quantity processing step, a co-occurrence matrix in the image of the measurement target acquired in the image acquisition step is obtained, and a correlation value between a row and a column in the obtained co-occurrence matrix is obtained as the statistical feature quantity. A particle size measuring method.

6. On a computer, An image acquisition step of acquiring an image of the measurement target obtained by imaging the particulate matter to be measured; A statistical feature quantity processing step of obtaining a statistical feature quantity based on the relationship between each pixel value at a first pixel and a second pixel within a predetermined range with respect to the first pixel in the image of the measurement target acquired in the image acquisition step; A particle size measurement program that executes a particle size processing step of obtaining a particle size corresponding to the statistical feature amount obtained in the statistical feature amount processing step by using correspondence information representing the correspondence between the statistical feature amount and the particle size. The statistical feature amount processing step obtains a co-occurrence matrix in the image of the measurement target obtained in the image acquisition step, and obtains a correlation value between rows and columns in the obtained co-occurrence matrix as the statistical feature amount. Particle size measurement program.

7. A granulation unit that granulates particulate matter from raw materials under predetermined granulation conditions, The particulate matter granulated by the granulation unit, and the particle size measurement device according to any one of claims 1 to 4 for obtaining the particle size of the particulate matter as the measurement target. And an adjustment unit that adjusts the predetermined granulation conditions based on the particle size of the particulate matter obtained by the particle size measurement device. Granulation device.

8. The particulate matter is an iron ore granulated product obtained by adding quicklime as a binder to powdered iron ore as the raw material and adding a predetermined amount of moisture for granulation. The adjustment unit adjusts at least one of the mixing ratio when the powdered iron ore contains a plurality of types, the addition amount of the quicklime, and the predetermined amount of the moisture. The granulation device according to claim 7.

9. A granulation step of granulating particulate matter from raw materials under predetermined granulation conditions, The particulate matter granulated in the granulation step, and the particle size measurement method according to claim 5 for obtaining the particle size of the particulate matter as the measurement target. And an adjustment step of adjusting the predetermined granulation conditions based on the particle size of the particulate matter obtained by the particle size measurement method. Granulation method.

Images