JP2018135599A - Inspection method of carbonaceous inner package granular particles and production method of carbonaceous inner package sintered ore - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of confirming an inner package state of carbonaceous core without destroying carbonaceous inner package granular particles.SOLUTION: An inspection method of carbonaceous inner package granular particles obtained in such a manner that iron ore powder and a lime-containing raw material are mixed to form a mixed powder, and a granulation raw material containing carbonaceous cores and the mixed powder is granulated to form an exterior layer of the mixed powder on the surrounding of the carbonaceous cores includes to calculate at least one of a carbonaceous core content, a carbonaceous core diameter and a thickness of the exterior layer of the mixed powder using transmission image data generated by transmission imaging the carbonaceous inner package granular particles.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a technique for producing sintered ore used as an iron-containing raw material in a blast furnace or the like. Specifically, the present invention relates to a method for inspecting carbon material-containing granulated particles and charcoal using carbon material-containing granulated particles. The present invention relates to a method for producing a material interior sintered ore.

In the blast furnace iron manufacturing method, iron-containing raw materials such as sintered ore, iron ore, and pellets are mainly used as iron sources. Here, the sintered ore means, in addition to iron ores having a particle size of less than 10 mm, various kinds of dust generated in the ironworks, refined nickel slag, SiO ₂ -containing raw materials such as silica and serpentine, limestone and quicklime, etc. Add a suitable amount of water to a granulated raw material composed of lime-containing raw material, solid fuel such as powdered coke and anthracite, etc., and mix and granulate using a drum mixer etc. The sintered raw material is charged into a circulating pallet of the sintering machine, the solid fuel contained in the granulated particles is burned and sintered, and the resulting sintered cake is crushed, sized and fixed. It is a kind of agglomerated mineral that has been collected as a product with a particle size of more than.

  In recent years, attention has been paid to agglomerates in which iron sources such as iron ore and iron-making dust and carbon materials such as small coke are arranged close to each other. The reason for this is that when an iron source such as iron ore and a carbon material are placed close together in one agglomerate, a reduction reaction (exothermic reaction) on the iron source side and a gasification reaction (endothermic reaction) on the carbon material side This is because the iron-making reaction efficiency is improved because it occurs repeatedly at a high speed, and the temperature in the furnace can be lowered without lowering the productivity of the blast furnace.

  As a method for producing such agglomerated ore, in Patent Document 1, carbon material-containing granulated particles coated with a carbonaceous material with iron ore powder and a CaO-containing raw material were produced, and this was granulated with a normal sintered raw material. A method of sintering in a downward suction type sintering machine after mixing with granulated particles is disclosed.

Japanese Patent No. 5790966

  The interior condition of the carbonaceous material core in the carbonized material interior granulated particles described in Patent Document 1 is not necessarily constant, and depending on the granulation conditions, the outer layer may not be formed with a sufficient thickness, It may not be done. In order to confirm the interior condition of the carbonaceous material core in the carbonized material interior granulated particles, there is a problem that it can be confirmed only by destructive inspection such as cutting the granulated particles. The present invention has been made in view of the above problems, and its purpose is to calculate a management index for quickly managing the quality of carbonaceous material-containing granulated particles without destroying the carbonaceous material-containing granulated particles. An object of the present invention is to provide a method for inspecting carbon material-containing granulated particles.

The features of the present invention for solving such problems are as follows.
(1) An iron oxide ore powder and a lime-containing raw material are mixed to form a mixed powder, and a granulated raw material containing the carbonaceous material core and the mixed powder is granulated, so that the outer layer of the mixed powder is disposed around the carbonaceous material core. A method for inspecting carbonaceous material-incorporated granulated particles formed using the transmission image data generated by transmission imaging of the carbonaceous material-internally granulated particles, And at least one of the thicknesses of the outer layers of the mixed powder, and the method for inspecting the carbonaceous material-containing granulated particles.
(2) The inspection method for carbon material-containing granulated particles according to (1), wherein the transmission photography is performed using X-rays or terahertz waves that can pass through the carbon material-containing granulated particles.
(3) The carbonaceous material-containing granulated particles, wherein the carbonaceous material core content is calculated by the method for inspecting the carbonized material-incorporated granulated particles according to (1) or (2), and contains the carbonaceous material nuclei with respect to the sintered raw material A method for producing a carbonaceous material-containing sintered ore, wherein the mixing ratio of the carbonized material-internally granulated particles to the sintered raw material is adjusted according to the carbonaceous material core content so that the ratio of the carbonaceous material is constant.

  By using the inspection method for the carbonaceous material-incorporated granulated particles according to the present invention, the carbonaceous material-incorporated granulated particles are confirmed without being destroyed, and the carbonaceous material-internally granulated particles are confirmed. It is possible to calculate at least one of the carbon material core content, the carbon material core particle size, and the thickness of the outer layer of the mixed powder, which is a particle management index. By controlling the granulation of the carbonaceous material-incorporated granulated particles with the management index, the carbonaceous material-incorporated granulated particles having stable quality can be granulated.

It is the conceptual diagram which showed the relationship between the reduction | restoration reaction rate in a blast furnace, and the distance between carbonaceous material and iron containing raw materials. It is the conceptual diagram which showed the relationship between the heat exchange, the reduction reaction of an iron ore, and the gasification reaction of a carbonaceous material (coke) when an iron ore and a carbonaceous material are adjoining. It is a schematic diagram which shows an example of the manufacturing method of a carbonaceous material interior granulated particle | grain including the inspection method of the carbonaceous material interior granulated particle which concerns on this embodiment. It is the transmission image of the carbonaceous material interior granulated particle 32. It is a photograph which shows the condition which installed the carbonaceous material interior granulated particle in the sample stand 62.

  In the blast furnace ironmaking process, iron-containing raw materials such as iron ore and sintered ore are heated to a high temperature by the combustion heat of carbonaceous materials such as coke and reduced to produce pig iron. At this time, in order to improve the air permeability in the blast furnace, the iron-containing raw material is charged from the top of the blast furnace in a layered manner by separating the iron-containing raw material and the carbonaceous material. On the other hand, from the viewpoint of increasing the reduction reaction rate of the iron-containing raw material, it is preferable to reduce the distance between the iron-containing raw material and the carbonaceous material, but in order to reduce the distance between the iron-containing raw material and the carbonaceous material, When the thickness of the raw material layer and the carbon material layer is reduced, the air permeability in the blast furnace is deteriorated, and on the contrary, the reduction reaction rate is reduced.

  Therefore, ferro-coke, carbonaceous material-containing sintered ore, and ultrafine technology have been studied as methods for increasing the reduction reaction rate. FIG. 1 is a conceptual diagram showing the relationship between the reduction reaction rate in the blast furnace and the distance between the carbonaceous material and the iron-containing raw material. Here, ferro-coke is an iron-making raw material that is baked and hardened after mixing and forming a carbonaceous material and an iron-containing raw material. Carbonaceous material interior is a technology that uses an iron-containing raw material with carbonaceous material as an iron-making raw material, and ultra-miniaturization is a technology that mainly uses finely refined carbonaceous material.

The concept of these technologies is based on the theory shown in FIG. FIG. 2 is a diagram schematically showing the phenomenon in the blast furnace, FIG. 2 (a) shows a conceptual diagram of the phenomenon in the conventional blast furnace, and FIG. 2 (b) shows the iron ore and the carbonaceous material. The conceptual diagram of the phenomenon in a blast furnace at the time of arranging close is shown. On the iron ore side, Fe ₂ O ₃ and CO react with each other to cause a reduction reaction to become Fe and CO ₂ . This reaction is an exothermic reaction. On the other hand, on the carbonaceous material side, a gasification reaction (gas reforming reaction) called “Budwar reaction” in which CO ₂ and C react to generate CO occurs. This reaction is an endothermic reaction (in the following description, the reduction reaction and the gasification reaction are collectively referred to as “iron-making reaction”).

Here, as shown in FIG. 2 (a), in a conventional blast furnace in which an iron-containing raw material and a carbonaceous material are charged in layers in a blast furnace, gasification that is an exothermic reaction and an endothermic reaction. The reaction takes place in different places. For this reason, the movement of gas is required for the transfer of heat necessary for the reaction and the supply of CO and CO ₂ . On the other hand, as shown in FIG. 2B, when the iron-containing raw material and the carbon material are arranged close to each other, the reduction reaction that is an exothermic reaction and the gasification reaction that is an endothermic reaction are repeated at a high rate. Iron-making reaction efficiency is improved. Therefore, it is considered that placing the iron-containing raw material and the carbonaceous material close to each other is effective in increasing the iron-making reaction efficiency. Under such an idea, the carbonaceous material-containing sintered ore in which the carbonaceous material core is embedded in the iron-containing raw material is an ideal form.

Further, in the carbon material-containing sintered ore, when the heat necessary for the gasification reaction reaches the inside of the carbon material-containing sintered ore, the reduction of Fe _n O _m by the CO generated by the gasification reaction is reduced. As the reaction takes place and the CO ₂ generated by the reduction reaction causes the next gasification reaction, the reaction takes place in a chain from the inside of the agglomerate to the outside, and the Fe _n O _{m in the} inside sequentially It is self-reduced to produce Fe (metallic iron). Thus, since the reduction reaction and the gasification reaction proceed inside the agglomerate, the heat supply from the outside can be reduced, and the furnace temperature can be lowered accordingly.

  In this way, it is a carbonaceous material-containing sintered ore that can increase the efficiency of iron making reaction and lower the temperature in the furnace, but to realize this, it is necessary to be able to stably manufacture the carbonaceous material-containing sintered ore, For this purpose, the quality is such that the carbonaceous material is embedded in the granulation stage, and that a dense outer layer is formed with a sufficient thickness so that the carbonaceous material core does not disappear during sintering. It is necessary to granulate stable carbonaceous material-containing granulated particles.

  Therefore, the present inventors have examined a method for inspecting the carbonaceous material-incorporated granulated particles that can inspect the interior state of the carbonaceous material in the granulated carbonaceous material-internally granulated particles. Using the transmitted image, the carbon material core content, which is the ratio of the carbon material-containing granulated particles to the total granulated particles, the particle size of the carbon material embedded as the carbon material core, The present invention has been completed by finding that the thickness of the outer layer of the mixed powder covering the periphery of the material core can be calculated, and that these can be used as a management index to manage the carbonaceous material-containing granulated particles. Hereinafter, the present invention will be described through embodiments of the present invention.

  FIG. 3 is a schematic view showing an example of a method for producing a carbonaceous material-containing sintered ore including a method for inspecting carbonaceous material-containing granulated particles according to the present embodiment. A predetermined amount of iron ore powder 16 stored in the storage tank 10 is cut out by the transporting machine 14. Similarly, a predetermined amount of the lime-containing raw material 18 stored in the storage tank 12 is also cut out by the conveyor 14. The iron ore powder 16 and the lime-containing raw material 18 are conveyed to the kneader 20 by the conveyor 14. The iron ore powder 16 and the lime-containing raw material 18 are uniformly stirred and mixed by a kneader 20 together with an appropriate amount of water 19 to be mixed powder 22.

  As the iron ore powder 16 used in the present embodiment, it is preferable to use an iron ore having a particle size of 10 μm or more and less than 1000 μm, and more preferably a pellet feed having a particle size of 10 μm or more and less than 250 μm. . This pellet feed is a fine ore with a particle size of 10 μm or more and less than 250 μm of 90% by mass or more, mainly composed of high-grade (high Fe, low gangue) hematite and magnetite, and a large amount at a low cost. It is excellent in that it can be obtained. If the particle diameter is within the above range, in addition to pellet feed, mill scale, converter exhaust gas recovery dust (OG dust), tailing generated during the beneficiation, etc. may be used. A mixture may be used.

  A predetermined amount of the mixed powder 22 that has been uniformly stirred and mixed by the kneading machine 20 is cut out to the conveying machine 24. Further, the coke particles 28 stored in the storage tank 26 are also cut out by a predetermined amount by the transporter 24 to become a granulated raw material including the mixed powder 22 and the coke particles 28. The granulated raw material is conveyed to the granulator 30 by the conveyor 24.

  In the granulator 30, an appropriate amount of water 19 is supplied and stirred, so that the mixed powder 22 is coated around the coke particles 28 by the water cross-linking force of the supplied water. As a result, the carbonaceous material-inner granulated particles 32 in which the coke particles 28 are used as the carbonaceous material core and the outer layer of the mixed powder 22 is formed around the carbonaceous material core are manufactured. In the present embodiment, the carbonaceous material-containing granulated particles 32 do not necessarily mean granulated particles containing the coke particles 28, but a granulated raw material containing the coke particles 28 and the mixed powder 22 is granulated. It means a granulated particle containing granulated particles containing coke particles 28 and granulated particles not containing some coke particles 28.

  In the present embodiment, the size of the coke particles 28 serving as the carbon material core of the carbon material-containing granulated particles 32 is preferably 3 mm or more and less than 10 mm from the viewpoint of preventing combustion / disappearance during sintering. The thickness of the outer layer formed around the coke particles 28 is preferably 2 mm or more and less than 8 mm. If the thickness of the outer layer is less than 2 mm, it may not function sufficiently as an oxygen barrier layer even if it is melted during sintering, and the coke particles 28 have many irregularities, so that the carbon material core may not be completely covered. There is. Usually, since the granulated particles are heated from the outside, if the thickness of the outer layer is increased, it becomes difficult to raise the temperature at the center side during heating. Therefore, the thickness of the outer layer is preferably less than 8 mm. From the same viewpoint, the thickness of the outer layer is more preferably 3 mm or more and less than 7 mm. Furthermore, it is preferable to control the particle size of the carbon material-containing granulated particles 32 within an appropriate range.

  The granulated carbonaceous material granulated particles 32 thus granulated are transported by the transporter 34 and the state of the carbonaceous material interior is inspected by the inspection device 36 installed in the transporter 34. The inspection device 36 is, for example, a device having an X-ray transmission imaging unit and an image analysis unit. The X-ray transmission imaging unit transmits X-rays to the carbonaceous material-containing granulated particles 32 moved to the X-ray irradiation region on the transport device 34, detects the transmitted X-rays with a flat panel for X-rays, and transmits the transmitted image. Generate data. The X-ray transmission conditions may be any conditions as long as the coke particles 28 and the surrounding mixed powder 22 can be distinguished. For example, a tube voltage of 80 kV to 150 kV is desirable. Further, the transmission imaging may be performed as it is on the transport device 34, but it is more preferable to perform the transmission imaging by arranging the carbonaceous material-inner granulated particles so as not to overlap with each other in the X-ray irradiation direction. In order to inspect more accurately, a part of the carbonaceous material-containing granulated particles 32 are moved to another line, and a predetermined quantity, for example, about 100 to 200, preferably about 500 carbonaceous material-containing granulated particles 32 are permeated. You may shoot.

  Next, image analysis by the image analysis unit will be described. FIG. 4 shows a transmission image of the carbonaceous material-containing granulated particles 32. FIG. 4A shows a transmission image of the carbonaceous material-containing granulated particles 32. FIG. 4B shows a transmission image of the carbonaceous material-containing granulated particles 32 in which the coke particles 28 are embedded. FIG. 4C shows a transmission image of the carbonaceous material-containing granulated particles 32 in which the coke particles 28 are not provided. As can be seen from FIGS. 4A and 4C, in the transmission image, the background is displayed whitest, the coke particles 28 are displayed in gray, and the mixed powder 22 is displayed in black.

  The image analysis unit specifies an image region indicating the coke particles 28 and an image region indicating the mixed powder 22 in the transmission image data using the luminance value of the transmission image data. The image analysis unit uses the coke particles 28 and the coke particles 28 used to identify the image region of the outer layer of the mixed powder 22 outside the coke particles 28 by analyzing the past transmission image data taken through the same transmission imaging conditions. The luminance value that defines the boundary between 28 and the mixed powder 22 (in the following description, the luminance value that defines the boundary between the coke particles 28 and the mixed powder 22 is referred to as “threshold”) is stored. The image analysis unit specifies an image data region indicating the coke particles 28 in the transmission image data and an image data region indicating the outer layer of the mixed powder 22 outside the coke particles 28 using the threshold value.

  Alternatively, carbonaceous material-containing granulated particles for standard measurement may be prepared, the carbonized material-containing granulated particles may be periodically transmitted and photographed by an X-ray transmission imaging unit, and the stored threshold value may be updated. The state of the X-ray tube or device may vary depending on the use of the device. By updating the threshold value as described above, even if the state of the X-ray tube or the apparatus changes, the threshold value is also updated in response to the change, so that the coke particles 28 are the same as before the state changes. And an image data region indicating the outer layer of the mixed powder 22 outside the coke particles 28 can be specified.

  For example, when calculating the particle size (carbon material core particle size) of the coke particles 28, the image analysis unit detects the contour of the image data region indicating the identified coke particles 28, and calculates the perimeter of the contour. To do. The image analysis unit calculates the particle size of the coke particles 28, assuming that the equivalent circular equivalent diameter is the particle size of the coke particles 28 (carbon material core particle size).

Further, for example, when calculating the thickness of the outer layer of the mixed powder 22, the image analysis unit specifies the carbonaceous material-containing granulated particles 32 having the coke particles 28 from the presence or absence of the image data region indicating the coke particles 28. The image analysis unit detects the contour of the image data area indicating the outer layer of the mixed powder of the specified carbonaceous material-containing granulated particles 32, and calculates the perimeter of the contour. The image analysis unit calculates the particle diameter of the carbonaceous material-containing granulated particles 32 on the assumption that the circumference equivalent circle diameter having the same peripheral length is the particle diameter of the carbonized material-containing granulated particles 32. Further, the image analysis unit calculates the particle size of the coke particles 28 embedded in the identified carbonaceous material-containing granulated particles 32 by the method described above. The image analysis unit mixes using the calculated particle diameter of the carbonaceous material-containing granulated particles 32, the particle diameter of the coke particles 28 embedded in the carbonaceous material-containing granulated particles 32, and the following equation (1). The thickness of the outer layer of the powder 22 is calculated.
“Outer layer thickness” = (“Particle size of carbonaceous material-inner granulated particles” − “Particle size of coke particles”) / 2 (1)

  In addition, for example, when calculating the carbonaceous material core content rate, the image analysis unit identifies an image data region indicating the outer layer of the mixed powder 22 and an image data region indicating the coke particles 28, and the image data region The numbers of the carbonaceous material-inner granulated particles 32 and the coke particles 28 are specified from the number. The image analysis unit calculates the carbon material core content by dividing the number of the specified coke particles 28 by the number of the specified carbon material interior granulated particles 32 and multiplying by 100.

  As described above, the image analysis unit uses the transmission image data obtained by photographing the carbon material-containing granulated particles 32, and uses at least one of the carbon material core content rate, the carbon material core particle size, and the thickness of the outer layer of the mixed powder. Calculate one. And when at least one of the calculated carbon material core content rate, the carbon material core particle size, and the thickness of the outer layer of the mixed powder does not satisfy a predetermined standard, the carbon material internal granulation of the same lot The particles 32 are determined to be defective, and the carbonaceous material-containing granulated particles 32 of the lot determined to be defective may be crushed and granulated again to obtain a normal sintered raw material. Thus, the quality stable carbon material is managed by managing the carbon material interior granulated particles 32 using at least one of the carbon material core content rate, the carbon material core particle size, and the thickness of the outer layer of the mixed powder as a management index. The interior granulated particles 32 can be used to stably produce a carbonaceous interior sintered ore with stable quality.

  The charcoal-containing granulated particles 32 are inspected by the inspection device 36 and then cut out by the transporting device 42. In addition, normal granulated particles 40 without carbonaceous material cores are also cut out by a predetermined amount by a conveyor 42 and mixed to become a sintered raw material. Normal granulated particles include pulverized iron ore, lime-containing raw materials such as limestone and dolomite, granulation aids such as quick lime, and carbonaceous materials such as coke powder and anthracite (hereinafter referred to as “coagulating material”). And the like, and granulated using a granulator such as a drum mixer. The sintered raw material is charged into the pallet of the lower suction type sintering machine, sintered by the lower suction type sintering machine, and then crushed, cooled and sieved to produce a carbonaceous material-containing sintered ore. The carbonaceous material-containing sintered ore is charged into the blast furnace 60 as an iron-containing raw material.

  In the inspection method for the carbonaceous material-incorporated granulated particles 32 according to the present embodiment, the carbonaceous material core content rate, the carbonaceous material core particle size is obtained by using transmission image data generated by transmitting through the carbonaceous material-internally granulated particles 32. And at least one of the thicknesses of the outer layers of the mixed powder is calculated. Thereby, the carbonaceous material interior granulated particles 32 can be managed by using at least one of the carbonaceous material core content rate, the carbonaceous material core particle size, and the thickness of the outer layer of the mixed powder as a management index. The interior granulated particles 32 can be used to stably produce a carbonaceous interior sintered ore with stable quality. And, the carbonaceous material-containing sintered ore with stable quality is charged into the blast furnace as an iron-containing raw material, so that the iron-making reaction efficiency can be improved and the furnace temperature can be lowered without reducing the productivity of the blast furnace.

  In the present embodiment, the carbonaceous material-containing granulated particles 32 are cut into the conveying machine 42 by a predetermined amount, and the normal granulated particles 40 are cut into the conveying machine 42 by a predetermined amount to obtain a sintered raw material. Not limited to. For example, the mixing ratio of the carbonaceous material interior granulated particles 32 to the sintered raw material may be adjusted according to the carbonaceous material core content calculated by the inspection device 36. Specifically, when the carbon material core content rate calculated by the inspection device 36 is high, the mixing ratio of the carbon material interior granulated particles 32 to the sintered raw material is lowered, and when the carbon material core content rate is low. The mixing ratio of the carbonaceous material-containing granulated particles 32 to the sintered raw material is increased. Thereby, the ratio of the carbonaceous material-containing granulated particles 32 containing the coke particles 28 to the sintered raw material can be made constant.

  As described above, the use of carbonaceous material-containing sintered ore improves the iron-making reaction efficiency, but if the operating conditions of the blast furnace are not optimized according to the degree of improvement in the iron-making reaction efficiency, the internal state of the blast furnace fluctuates and the blast furnace The operation becomes unstable. On the other hand, if the ratio of the carbonaceous material-containing granulated particles 32 containing the coke particles 28 to the sintered raw material can be made constant, fluctuations in the degree of improvement in iron-making reaction efficiency can be suppressed, and thereby fluctuations in the internal state of the blast furnace can also be achieved. Suppressed and stable blast furnace operation becomes possible.

  Moreover, in this embodiment, although the carbon material interior granulated particle 32 showed the example imaged by transmission on the conveying machine 34, it is not restricted to this. For example, in the X-ray irradiation region, the carbonaceous material-incorporated granulated particles 32 may be separated from each other by a convex shape by being conveyed by a conveyor having a convex shape on the floor surface. Further, transmission imaging of the carbonaceous material-incorporated granulated particles 32 is not limited to X-rays, and it is only necessary to be able to discriminate the outer layer of the coke particles 28 and the surrounding mixed powder 22 by using transmission imaging. Transmission imaging may be performed.

  Furthermore, in this embodiment, although the example which calculates the particle size of the coke particle | grains 28 and the carbonaceous material interior granulation particle | grains 32 by the circumference equivalent circle diameter with the same circumference was shown, it is not restricted to this. For example, the image analysis unit calculates the area of the image data region indicating the identified coke particles 28 or the carbonaceous material-incorporated granulated particles 32, and the particle size of the coke particles 28 or the carbonaceous material-incorporated granulated particles 32 is the area. The diameter of the coke particles 28 or the carbonaceous material-containing granulated particles 32 may be calculated on the assumption that they have the same area circle equivalent diameter.

Example 1
Using a test mixing device and a granulating device, an experiment was conducted to granulate carbonaceous material-containing granulated particles using mixed powder obtained by mixing pellet feed and quicklime and coke particles. A 90% by mass pellet feed (hematite (Fe ₂ O ₃ ): 97.7% by mass) with a particle size of less than 250 μm and 10% by mass quicklime are mixed to obtain a mixed powder. 5 mass% of coke particles having a particle diameter of 3 mm as a core were mixed and granulated to prepare carbonaceous material-containing granulated particles. At this time, agglomerated particles not including the coke particles were prepared together with the carbonized particles including the coke particles, and the interior condition of the coke particles was inspected. In the experiment, an X-ray transmission device manufactured by Rigaku Corporation was used. The X-ray source was 3530CP, the X-ray detector was Xmar0707CF (Flat Panel 75 × 75 mm, pixel size 48 μm), the tube voltage was set to 120 kV, and the focus and detector distance was set to 800 mm.

  A transmission image obtained by the transmission imaging is shown in FIG. As described above, in the transmission image, the background is displayed whitest, the coke particles 28 are displayed in gray, and the mixed powder 22 is displayed in black. For this reason, as above-mentioned, by specifying the image data area | region which shows a coke particle | grain, and the image data area | region which shows the outer layer of the mixed powder 22, a carbon material nucleus content rate, a carbon material nucleus particle size, and the outer layer of mixed powder It is clear that at least one of the thicknesses can be calculated.

(Example 2)
The carbonaceous material interior granulated particles were prepared under the same conditions as in Example 1, and an experiment was conducted to inspect the interior condition of the carbonaceous material using the X-ray transmission method. Using an X-ray inspection apparatus manufactured by Matsusada Precision Co., Ltd., the X-ray tube voltage was set to 110 kV, the power was set to 20 W, the measurement time was set to 5 seconds for each granulated particle, and the interior condition of the carbonaceous material was inspected.

  FIG. 5 is a photograph showing a situation in which the carbonaceous material-containing granulated particles are installed on the sample table 62. As shown in FIG. 5, in Example 2, 125 carbonaceous material-incorporated granulated particles are placed on a sample table 62 having a length of 180 mm and a width of 400 mm. The movement was repeated, and 125 carbon material-containing granulated particles were photographed by transmission. The total shooting time excluding travel time was about 10 minutes.

  As a result of transmitting and photographing 125 carbonaceous material-containing granulated particles and specifying the image data area indicating the coke particles using the threshold value, the image data area indicating the coke particles in the 101 carbonaceous material-containing granulated particles is specified. In the 24 carbonaceous material-containing granulated particles, the image data area indicating the coke particles was not specified. The carbon material core content calculated from these results was 81%.

  After transmission photography, the carbon material-containing granulated particles were divided to confirm the presence or absence of coke particles. 101 carbon material-containing granulated particles contained coke particles, and 24 carbon material-containing granulated particles were Coke particles were not included, and the carbon material core content was 81%. From these results, the carbon material core content rate calculated using transmission image data generated by transmission photography and the carbon material core content rate confirmed by dividing the carbon material interior granulated particles are the same. It was confirmed that the carbonaceous material core content rate of the carbonaceous material interior granulated particles can be calculated by using the inspection method of the carbonaceous material interior granulated particles according to the embodiment.

  In addition, in Example 2, the example which permeate | transmits one carbonaceous material granulation particle | grain with 1 visual field was shown, However, You may carry out the radiographic imaging of several carbonaceous material interior granulated particle | grains with 1 visual field. In this case, the image analysis unit may analyze the plurality of carbonaceous material-incorporated granulated particles for each transmission image data, and connect the image data to produce transmission image data of 125 carbonaceous material-incorporated granulated particles. Then, the image data may be analyzed. Thereby, a large number of carbonaceous material-containing granulated particles can be photographed in a short time, and the inspection time of the carbonaceous material-containing granulated particles can be reduced.

DESCRIPTION OF SYMBOLS 10 Storage tank 12 Storage tank 14 Conveyor 16 Iron ore powder 18 Lime containing raw material 19 Water 20 Kneading machine 22 Mixed powder 24 Conveyor 26 Storage tank 28 Coke particle 30 Granulator 32 Carbonaceous material granulated particle 34 Conveyor 36 Inspection apparatus 40 Normal granulated particles 42 Conveyor 50 Sintering machine 60 Blast furnace 62 Sample stand

Claims (3)

Mixing iron ore powder and lime-containing raw material to make a mixed powder,
By granulating a granulated raw material containing a carbonaceous material core and the mixed powder, an inspection method of carbonized material-containing granulated particles in which an outer layer of the mixed powder is formed around the carbonaceous material core,
Using transmission image data generated by transmission imaging of the carbonaceous material-containing granulated particles, calculating at least one of the carbonaceous material core content rate, the carbonaceous material core particle size, and the thickness of the outer layer of the mixed powder, Inspection method for granulated particles of carbon material interior.   2. The inspection method for carbon material-containing granulated particles according to claim 1, wherein the transmission photographing is performed using X-rays or terahertz waves that can penetrate the carbon material-containing granulated particles.   The said carbon material nucleus content rate is computed with the inspection method of the carbon material interior granulated particle of Claim 1 or Claim 2, and the ratio of the carbon material interior granulated particle containing the said carbon material nucleus with respect to a sintering raw material is set. A method for producing a carbonaceous material-containing sintered ore, wherein a mixing ratio of the carbonaceous material-containing granulated particles to a sintered raw material is adjusted according to the carbonaceous material core content so as to be constant.