Loading device for powders and granular materials, and method for loading powders and granular materials.

Abstract

To provide a loading device for powders and granules that can load them in an appropriate distribution pattern. [Solution] The granular material loading device includes a loading section for loading granular material, a supply port for supplying the granular material to the loading section, and a discharge port for discharging the granular material from the loading section. The loading section includes a bottom, a wall formed by erecting from the bottom, and a vibration applying section for applying vibration to the loading section. The vibration applying section includes a magnetic force generating section for generating magnetic force and a movable section that reciprocates due to the magnetic force generating section, and is provided such that the direction of the reciprocating motion of the movable section forms an angle with respect to the wall of the loading section.

Description

Technical Field

[0001] The present invention relates to a granular material loading device for loading granular materials and a method for loading granular materials.

Background Art

[0002] One of the granular materials is a raw material for coke. High-quality caking coal serves as a raw material for coke. Caking coal has been on an upward price trend due to excessive demand in recent years. To address this problem, new coke production technologies such as the "formed coal blending method" for using low-grade coal have been developed.

[0003] In the formed coal blending method, at least a part of the coal charged into the coke oven is replaced with formed coal. Formed coal is produced by mixing crushed coal and a binder and subjecting them to pressure molding.

[0004] Formed coal is transported to the coke oven via a loading device such as a hopper, chute, or belt conveyor. When the formed coal is charged into the coke oven, not only the case where only the formed coal is charged into the coke oven but also the case where a mixture of formed coal and pulverized coal is charged may occur.

[0005] Formed coal is molded with coal particles in a state of being close to each other. When such formed coal is heated to be softened or melted, fusion is promoted. Therefore, in formed coal, the blending ratio of low-grade non-caking coal can be increased. As the raw material for coke, the higher the blending ratio of formed coal to the total coal, the more non-caking coal can be used.

[0006] Also, by blending formed coal into the raw material for coke, the average bulk density of the coal increases, so the amount of coal charged can be increased, and the productivity of coke can be enhanced.

[0007] Molded coal has a different moisture content than powdered coal. When molded coal and powdered coal are mixed and charged into a coke oven, the molded coal segregates in the coke oven. In other words, segregation of molded coal in the coke oven leads to an uneven distribution of moisture in the loaded material.

[0008] The rate at which carbon deposits adhere to the walls of a coke oven is affected by the moisture content of the coke material. Therefore, uneven moisture content in the coke material in a coke oven can lead to an uneven carbon deposit rate on the oven walls. This can result in problems such as coke oven clogging.

[0009] To avoid such problems, measures to prevent segregation of molten coal are being considered. Segregation of molten coal in coke ovens is thought to be partly caused by particle size segregation of the raw materials in the coal tower located upstream of the coke oven.

[0010] One of the factors that causes particle size segregation of raw materials in coal towers is the Brazil nut effect in the upper conveyor. The Brazil nut effect is a phenomenon in which, when vibration is applied to powders or granules with a particle size distribution, the relatively larger particles float to the surface, while the relatively smaller particles sink to the lower layers.

[0011] The Brazil nut effect can also occur on the raw material conveyor that transports the raw materials to the coal tower. As a result, the raw materials are supplied to the coal tower in a state where the coarse-grained molded coal is on the surface and the fine-grained pulverized coal is on the bottom.

[0012] As an example of countermeasures against the Brazil nut effect, Patent Document 1 discloses a method of reversing the relative positions of coarse and fine grains by installing a segregation adjustment plate on the raw material's trajectory and causing the raw material to fall in reverse. [Prior art documents] [Patent Documents]

[0013] [Patent Document 1] Special Publication No. 57-61809 [Overview of the project] [Problems that the invention aims to solve]

[0014] Incidentally, the inventors discovered that a factor causing segregation in the coal tower is the pile of raw materials formed by the raw materials falling from the raw material conveyor. Specifically, the inventors found that when raw materials are supplied to the coal tower, coarse grains roll along the ridge of the pile of raw materials, and the coarse grains undergo size segregation at the base of the pile.

[0015] However, the method described in Patent Document 1 could not improve the particle size segregation of coarse grains caused by the shape of the raw material pile, and further improvement in particle size segregation of the raw material was desired.

[0016] This invention has been made in view of the above-mentioned problems, and aims to provide a loading device for powders and granules that can load powders and granules in an appropriate distribution manner. [Means for solving the problem]

[0017] To solve the above problems, the present invention has the following features. [1] A loading device for granular materials, comprising: a loading section for loading granular materials; a supply port for supplying the granular materials to the loading section; and a discharge port for discharging the granular materials from the loading section, The loading section has a bottom, a wall formed by erecting from the bottom, and a vibration applying section that applies vibration to the loading section. The vibration-applying unit comprises a magnetic force generating unit that generates a magnetic force and a movable unit that reciprocates due to the magnetic force generating unit, and the direction of the reciprocating motion of the movable unit is provided to form an angle with respect to the wall of the loading unit, wherein the loading device for powders and granules is configured such that. [2] The loading section has a conveying section that conveys the powder and granules toward the discharge port, The powder loading device according to [1], wherein the direction of the reciprocating motion of the movable part is provided to form an angle with respect to the wall of the conveying part. [3] The vibration applying part is provided in plural at positions facing each other, and is the loading device for granular materials according to [1] or [2]. [4] A method for loading granular materials using the loading device for granular materials according to any one of [1] to [3], comprising: a supply step of supplying the granular materials from the supply port toward the loading part; a vibration applying step of applying vibration to the wall part of the loading part; and is the method for loading granular materials having these. [5] In the vibration applying step, vibration with a frequency of 5 Hz or more is applied, and is the method for loading granular materials according to [4]. [6] In the vibration applying step, when the amplitude of the vibration is A and the equivalent spherical diameter of the coarsest particles among the granular materials is d, vibration satisfying the following formula is applied, and is the method for loading granular materials according to [4] or [5]. 1 ≦ A / d ≦ 5

Advantages of the Invention

[0018] According to the loading device for granular materials of the present invention and the like, it has a vibration applying part that applies vibration to the loading part for loading granular materials. Further, the vibration applying part has a magnetic force generating part that generates magnetic force and a movable part that reciprocates by the magnetic force generating part. Further, the vibration applying part is provided such that the direction of reciprocation of the movable part forms an angle with the wall part of the loading part. Thereby, it becomes possible to apply vibration to the loading part via the wall part. Further, the vibration is applied in a direction intersecting the standing direction of the wall part. Thereby, it becomes possible to adjust the formation mode of the pile of raw materials loaded in the loading part. As a result, it is possible to suppress the particle size segregation of the granular materials in the loading device for granular materials.

Brief Description of the Drawings

[0019] [Figure 1] It is an explanatory view showing the configuration of the loading device for granular materials. ​​​​This is an explanatory diagram showing how the vibration-applying unit is attached to the wall of the loading section. [Figure 4] This is a flowchart illustrating a method for loading powders and granules using a powder loading device. [Figure 5] This is an explanatory diagram showing the overview of a vibratory feeder. [Figure 6] This graph shows the maximum proportion of molded coal when the direction of vibration is changed. [Figure 7] This graph shows the maximum proportion of molded charcoal when the ratio of amplitude to the equivalent diameter of the granular material is changed. [Figure 8] This graph shows the maximum proportion of molded charcoal produced when the vibration frequency is changed. [Modes for carrying out the invention]

[0020] Embodiments of the present invention will be described below with reference to the drawings. Figure 1 shows the configuration of the powder and granular material loading device 100. As the powder and granular material PD, a mixture of two or more types with different average particle sizes can be used, for example, molded charcoal and powdered charcoal. In other words, any mixture in which the Brazil nut effect can occur can be used as the powder and granular material PD.

[0021] The granular material PD is not limited to a mixture of molded coal and powdered coal; for example, two or more materials with different average particle sizes may be used from among sintered ore, molded coal, HBI (Hot Briquetted Iron) limestone, mudstone, silica, etc. In this embodiment, the granular material loading device 100 will be described as an example in which it is used as a loading device for a mixture of molded coal and powdered coal.

[0022] The granular material loading device 100 is not particularly limited as long as it can load granular material, but for example, it is a hopper used as a coal tower. The granular material loading device 100 has a loading section 10 for loading granular material PD.

[0023] The loading section 10 is not particularly limited in shape, but for example, it is formed in a box shape. That is, the loading section 10 has a bottom 11 and wall sections 12 that surround the bottom 11. In addition, there are multiple wall sections 12 that are positioned opposite each other.

[0024] In the example shown in Figure 1, multiple loading sections 10 are provided adjacent to each other. The top of the loading sections 10 is formed as an opening. A cover section 20 is provided above the loading sections 10 to close the opening.

[0025] The lid portion 20 is provided with a supply port 21 for supplying granular material PD to the loading portion 10. Below the loading portion 10, there is an outlet 13 for discharging the granular material PD to the outside. The outlet 13 is not particularly limited, but for example, there are 16 outlets in total, arranged in 4 rows of 4.

[0026] The granular material PD supplied from the supply port 21 is accumulated in the loading section 10. The granular material PD accumulated in the loading section 10 is then discharged to the outside through the discharge port 13.

[0027] A belt conveyor (not shown) is connected to the discharge port 13. The granular material PD discharged from the discharge port 13 is transported, for example, to a coke oven (not shown) by the belt conveyor.

[0028] The wall portion 12 of the loading section 10 is provided with a vibration-applying section 30 that applies vibration to the loading section 10. In the example shown in Figure 1, two vibration-applying sections 30 are provided at positions facing each other.

[0029] Figure 2 shows the top view of the powder and granular material loading device 100. As shown in Figure 2, in this embodiment, the loading section 10 is formed in a rectangular shape when viewed from above. The loading section 10 is provided in four locations so that it forms a ring when viewed from above.

[0030] The lid portion 20 is provided to close the opening of each loading section 10. The supply port 21 of the lid portion 20 is provided at a position corresponding to the center of each loading section 10.

[0031] A conveyor 40 is provided in the center of the lid 20 to transport the powder PD to the supply port 21. A chute 50 is provided at the front of the conveyor 40. The conveyor 40 is mounted on the lid 20 so as to be able to rotate on a rotating track 41. Each of the four supply ports 21 is located on the rotating track 41. In the example shown in Figure 2, the supply ports 21 are located at 90° intervals on the rotating track 41.

[0032] In the example shown in Figure 2, four vibration-applying units 30 are provided at positions facing each other. When multiple vibration-applying units 30 are provided in this manner, it is preferable to operate each vibration-applying unit 30 simultaneously to apply vibration. By operating the vibration-applying units 30 in this way, vibration can be continuously applied to the loading unit 10.

[0033] Figure 3 shows an embodiment in which the vibration-applying unit 30 is attached to the wall portion 12 of the loading portion 10. The vibration-applying unit 30 has a magnetic force generating unit 31 that generates magnetic force and a movable part 32 that reciprocates due to the magnetic force generating unit 31.

[0034] The magnetic field generating unit 31 has a magnetic path member 33 that has magnetic permeability. The magnetic path member 33 is formed of a magnetic permeability material such as iron. The magnetic path member 33 is not particularly limited, but for example, it is formed in a cylindrical shape.

[0035] The magnetic path member 33 has a bearing portion 33a formed through its center in the thickness direction. A bearing 33b is provided in the bearing portion 33a. An excitation coil 34 and a drive coil 35 are housed in the magnetic path member 33. The excitation coil 34 and the drive coil 35 are provided so as to cover the bearing portion 33a.

[0036] The excitation coil 34 is positioned such that a constant magnetic flux flows through the magnetic path member 33 when a DC voltage is applied from a constant voltage source (not shown), thereby generating a static magnetic field that is perpendicular to the drive coil 35.

[0037] The movable part 32 has a cylindrical insertion part 32a. The insertion part 32a is formed to be insertable into the bearing part 33a and the bearing 33b of the magnetic force generating part 31. The insertion part 32a is provided so as to be slidable along the direction in which the bearing part 33a is formed.

[0038] The movable portion 32 has a vibration transmission portion 32b formed on one end of the insertion portion 32a. The vibration transmission portion 32b is not particularly limited, but for example, it is formed in a cylindrical shape so as to expand radially from the insertion portion 32a.

[0039] The vibration transmission section 32b is connected to the drive coil 35 at its edge. A pair of suspension springs 36 are provided on the circumferential surface of the vibration transmission section 32b. The suspension springs 36 are provided to connect the circumferential surface of the vibration transmission section 32b and the magnetic force generating section 31.

[0040] The drive coil 35 is connected to a vibration control device (not shown). The drive coil 35 generates a magnetic force in response to a control signal transmitted from the vibration control device. That is, the magnetic force generating unit 31 causes the movable part 32 to reciprocate in the direction along the formation direction of the bearing part 33a, represented by the dashed arrow in Figure 3, i.e., in the movable direction D1. In other words, the vibration control device vibrates the movable part 32 by reciprocating it in various ways by changing the pattern of the control signal.

[0041] Here, if vibration is applied in the direction along the wall surface of the wall section 12, that is, in the direction of the height of the raw material pile, the raw material pile will be eliminated, but there is a risk that the so-called Brazil nut effect will be promoted. For this reason, it is preferable that the vibration component is greater in the direction along the bottom of the loading section 10 than in the direction of the height of the raw material pile.

[0042] As shown in Figure 3, the vibration-applying unit 30 is provided such that the direction of movement D1, which is the direction of reciprocating motion of the movable part 32, forms an angle θ with respect to the wall portion 12 of the loading section 10. In this configuration, it is possible to apply vibration to the loading section 10 via the wall portion 12. Furthermore, the vibration is applied in a direction intersecting the vertical direction of the wall portion 12, that is, in a direction along the bottom of the loading section 10.

[0043] The angle θ is preferably 0° < θ < 180°, more preferably 45° ≤ θ ≤ 135°, and more preferably 60° ≤ θ ≤ 120°. By setting the angle θ in this way, vibration can be applied in a direction perpendicular to the wall surface of the wall portion 12.

[0044] More specifically, the vibration component can be increased in the direction perpendicular to the wall portion 12. As a result, it becomes possible to efficiently adjust the formation of the piles of raw materials loaded on the loading portion 10.

[0045] The method for loading powders and granules using the powder loading device described above will now be explained. Figure 4 shows the flow of the method for loading powders and granules using the powder loading device. As shown in Figure 4, a supply step is performed in which the powders and granules PD are supplied from the supply port 21 (step S01).

[0046] Next, a vibration application step is performed in which vibration is applied to the wall portion 12 of the loading portion 10 by activating the vibration application unit 30 (step S02).

[0047] In step S02, the vibration application step, it is preferable that the applied vibration is a sine wave. Furthermore, it is preferable that the vibration has a frequency of 5 Hz or higher. The frequency of the vibration is preferably 10 to 50 Hz, and more preferably 20 to 30 Hz. By applying vibration with a frequency of 5 Hz or higher, the time required to collapse the raw material pile can be shortened, and the dispersion improvement effect can be efficiently obtained.

[0048] Furthermore, it is preferable that the vibration applied in step S02 satisfies the following equation, where A is the amplitude of the vibration and d is the equivalent spherical diameter of the coarsest particle in the granular material PD (hereinafter also simply referred to as the equivalent spherical diameter). 1 ≤ A / d ≤ 5 (1)

[0049] In equation (1), the amplitude A of the vibration can be measured by a vibration meter. Alternatively, the amplitude A may be obtained by setting the vibration application unit 30. Furthermore, the equivalent spherical diameter d is not particularly limited, but can be measured, for example, by a sieve.

[0050] By setting A / d to 1 ≤ A / d, a sufficient amplitude can be obtained to break down the raw material pile, thereby enhancing the dispersion improvement effect of the powder PD. Furthermore, by setting A / d ≤ 5, it is possible to suppress the forceful collision of the powder PD with the wall 12 of the loading section 10 or other powder PDs, thereby suppressing cracking of the powder PDs.

[0051] Furthermore, in cases where coal or other materials are intended to be crushed, cracking of the granular material PD may not be a problem. Even in such cases, damage caused by collision between the wall portion 12 and the granular material PD can be reduced, thereby extending the lifespan of the equipment.

[0052] As described above, the vibration application step in step S02, in which vibration is applied to the wall portion 12, can cause the pile of raw materials formed in the supply step of step S01 to collapse. As a result, the surface of the pile of raw materials is smoothed, the base of the pile which is the segregation point of molded coal is eliminated, and segregation of molded coal is mitigated.

[0053] (Second Embodiment) In the embodiments described above, a hopper used as a coal tower was explained as an example of a granular material loading device. The granular material loading device is not limited to a hopper, but may also be, for example, a vibratory feeder. The granular material loading device according to the second embodiment will be described below, but components that are the same as those in the granular material loading device of the first embodiment will be denoted by the same reference numerals and their description will be omitted.

[0054] Figure 5 shows an overview of the vibratory feeder 200. As shown in Figure 5, the vibratory feeder 200 has a loading section 60 that is formed in the shape of a trough with an open top. The loading section 60 has a supply port 61 through which powder granular material PD is supplied to the loading section 60. In addition, an outlet 62 is formed at one end of the loading section 60 through which the powder granular material PD is discharged. The loading section 60 is formed such that its bottom 64 is surrounded by its wall 63.

[0055] In the example shown in Figure 5, the supply port 61 is connected to a chute 70 that guides the powdered material in a predetermined direction. The chute 70 is connected to a belt conveyor 80. That is, the powdered material PD supplied from the belt conveyor 80 to the chute 70 is discharged to the supply port 61 of the loading section 60.

[0056] The bottom 64 of the loading section 60 is provided with a cutting control unit (not shown) that applies vibration in the thickness direction of the bottom 64 while tilting the loading section 60 so that the discharge port 62 side is lower. In other words, by tilting the loading section 60 with the cutting control unit, the loading section 60 functions as a conveying unit that transports the powder PD toward the discharge port 62.

[0057] The wall sections 63 are formed in pairs, extending from one end to the other of the trough-like structure of the loading section 60. In the example shown in Figure 5, the wall sections 63 are formed facing each other.

[0058] It is preferable that the vibration-applying units 30 are provided on each of the opposing wall portions 63. Furthermore, it is preferable that the vibration-applying units 30 are provided at positions opposite to each other. By providing the vibration-applying units 30 in this manner, it becomes possible to apply vibration across the width direction of the loading portion 60.

[0059] Furthermore, in this embodiment, the raw material pile tends to form on the side of the loading section 60 where the chute 70 is located. In such cases, it is preferable that the vibration-applying unit 30 is located near the chute 70, that is, on the upstream side of the loading section 60. By providing the vibration-applying unit 30 in this way, the raw material pile can be leveled efficiently.

[0060] Furthermore, as described in the first embodiment, the vibration-applying unit 30 is preferably provided such that the movable direction D1 of the movable part 32 forms an angle with the wall 63. In this configuration, the vibration is applied in a direction intersecting the vertical direction of the wall 63, that is, in the width direction of the loading section 60.

[0061] Even with this configuration, it is possible to efficiently adjust the formation of the piles of raw materials loaded in the loading section 60. As a result, the base of the piles, which are segregation points for molded coal, is eliminated, and segregation of molded coal is mitigated. [Examples]

[0062] Using a 1 / 4 scale miniature test device that mimicked the powder and granular material loading device described in the above embodiment, we investigated the distribution pattern when raw materials were loaded into the powder and granular material loading device.

[0063] Sixteen collection boxes, designed to resemble coal towers, were installed. Using conveyors and chutes identical in shape to those installed in the actual machine, raw materials were loaded into the coal towers. The raw material composition consisted of 20% molded coal and 80% powdered coal. After loading 150 kg of raw materials into each collection box, the weight percentage of molded coal in each box was investigated.

[0064] The maximum value of the molten coal ratio obtained by comparing the molten coal ratio of 16 samples from the collection box was defined as the maximum molten coal ratio (mass%). The maximum molten coal ratio was used as an indicator of molten coal particle size segregation.

[0065] (Test Example 1) The effect of the direction of vibration applied by the vibration-applying unit on the segregation behavior of molded charcoal was investigated. For the investigation, the vibration frequency applied by the vibration-applying unit was set to 10 Hz. The amplitude A of the vibration was 150 mm, and the equivalent sphere diameter was 50 mm. The relationship between the vibration amplitude A and the equivalent sphere diameter d was set as follows. Amplitude A / Equivalent sphere diameter d=3

[0066] Comparative Example 1 was a case where no vibration was applied, Comparative Example 2 was a case where vibration was applied in the vertical direction (θ=0° or 180°) which is the height direction of the wall, and the Inventive Example was a case where vibration was applied in the horizontal direction (θ=90°) which is perpendicular to the wall. The maximum molded coal ratio [mass%] for each was investigated. Note that the angle θ is the angle between the direction of movement of the movable part and the wall of the loading part. The results are shown in Figure 6.

[0067] As shown in Figure 6, the inventive example had a significantly lower maximum molded charcoal content [mass%] than Comparative Examples 1 and 2. This indicates that segregation of molded charcoal was particularly reduced when the device was vibrated horizontally.

[0068] (Test Example 2) The effect of the relationship between vibration amplitude A and equivalent spherical diameter d on the segregation behavior of molded carbon was investigated. For the investigation, the vibration frequency from the vibration-applying unit was set to 10 Hz. The direction of vibration application was the horizontal direction (θ=90°) as in Test Example 1. In the test, the value of A / d was changed by varying the amplitude A under these conditions. The results are shown in Figure 7.

[0069] As shown in Figure 7, the inventive example achieved a lower maximum molten coal ratio than the comparative example where vibration was not applied. In particular, the maximum molten coal ratio was even lower when 1 ≤ A / d ≤ 5. When A / d > 5, there was a tendency for the molten coal to collide with the wall surface.

[0070] (Test Example 3) The effect of vibration frequency on the segregation behavior of molded charcoal was investigated. For the investigation, the direction of vibration was set to the horizontal direction (θ=90°) as in Test Example 1. In the tests, under these conditions, the relationship between the vibration amplitude A and the equivalent sphere diameter d was set as follows. Amplitude A / Equivalent sphere diameter d=3

[0071] In the experiment, the maximum proportion of molded coal was investigated when the vibration frequency was varied under these conditions. The results are shown in Figure 8.

[0072] As shown in Figure 8, the inventive example achieved a lower maximum molded charcoal ratio than the comparative example where vibration was not applied. In particular, the maximum molded charcoal ratio became even lower when the vibration frequency was 5 Hz or higher. [Explanation of Symbols]

[0073] 100 Loading device for powders and granules 10 Loading section 11 Bottom 12 Wall 13 Outlet 21 Supply port 30 Vibration-applying section 31 Magnetic force generating section 32 Moving parts 60 Loading section 64 Bottom 61 Supply port 62 Outlet 63 Wall 64 Bottom PD powder

Claims

1. A loading device for granular materials, comprising: a loading section for loading granular materials; a supply port for supplying the granular materials to the loading section; and a discharge port for discharging the granular materials from the loading section, The loading section has a bottom, a wall formed by erecting from the bottom, and a vibration applying section that applies vibration to the loading section. The vibration-applying unit comprises a magnetic force generating unit that generates a magnetic force and a movable unit that reciprocates due to the magnetic force generating unit, and the direction of the reciprocating motion of the movable unit is provided to form an angle with respect to the wall of the loading unit, wherein the loading device for powders and granules is configured such that.

2. The loading section has a conveying section that conveys the powder and granules toward the discharge port, The powder and granular material loading device according to claim 1, wherein the vibration-applying part is provided such that the direction of movement of the movable part is at an angle to the wall of the conveying part.

3. The powder and granular material loading device according to claim 1, wherein the vibration-applying units are provided in a plurality of positions facing each other.

4. The powder and granular material loading device according to claim 2, wherein the vibration-applying units are provided in a plurality of positions facing each other.

5. A method for loading powders and granules using a powder loading device according to any one of claims 1 to 4, A supply step of supplying the powdered material from the supply port toward the loading section, A vibration application step in which vibration is applied to the wall of the loading section, A method for loading powdered or granular materials, comprising the following characteristics.

6. The method for loading powdered or granular material according to claim 5, wherein in the vibration application step, vibration with a frequency of 5 Hz or higher is applied.

7. The method for loading granular materials according to claim 5, wherein in the vibration application step, vibrations satisfying the following equation are applied when the amplitude of the vibration is A and the spherical equivalent diameter of the coarsest particle among the granular materials is d. 1 ≤ A / d ≤ 5

8. The method for loading granular materials according to claim 6, wherein in the vibration application step, vibrations satisfying the following equation are applied when the amplitude of the vibration is A and the spherical equivalent diameter of the coarsest particle among the granular materials is d. 1 ≤ A / d ≤ 5

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