Method for supplying cement raw materials and method for producing cement clinker

Abstract

To provide a cement raw material feeder capable of suppressing adhesion of cement raw materials to an inner wall with a simple device configuration.SOLUTION: A cement raw material feeder 100 includes: a body part 10 having an internal space 12 where the cement raw material falls and configured to store the fallen cement raw material 50; an introduction part 20 where the cement raw material 50 is introduced from above the body part 10; a derivation part 30 where the cement raw material 50 is derived from below the body part 10; and a collision member 15A where only a part of the cement raw material 50 falling in the internal space 12 of the body part 10 collides to change the falling direction of the part.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a cement raw material supplying device, a cement clinker manufacturing facility, and a cement clinker manufacturing method. [Background technology]

[0002] A plurality of raw materials are used in the production of cement clinker. For this reason, a cement clinker production facility is provided with a raw material blending facility for blending the raw materials, and a grinding facility such as a raw material mill for grinding the blended raw materials. Patent Document 1 proposes a transport method using a belt conveyor to transport raw materials for cement production from the raw material blending facility to the grinding facility. Upstream or downstream of the belt conveyor, hoppers and tanks for temporarily storing the cement raw materials are provided to buffer the cement raw materials moving between each facility.

[0003] When using various raw materials, segregation may occur due to differences in particle size and density of the raw materials. For this reason, Patent Document 2 proposes providing a rotating chute at the bottom end of a hopper that charges raw materials into a bell-less blast furnace. This is an attempt to improve segregation caused by differences in particle size and density of raw material particles. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2020-147392 A [Patent Document 2] JP 2014-224293 A Summary of the Invention [Problem to be solved by the invention]

[0005] In a cement raw material supplying device, the amount of raw materials supplied to downstream equipment is adjusted. When such a cement raw material supplying device is operated continuously, cement raw materials may adhere to the inner walls of equipment such as a hopper and a tank. Once the deposits are formed on the inner walls, there is a concern that they may cause blockages in the equipment.

[0006] One of the causes of such deposits is that, when the cement raw materials fall through the internal space of the main body of the cement raw material supplying device, the distribution of particles becomes uneven due to differences in particle size and weight of the particles contained in the falling cement raw materials, causing a phenomenon in which coarse and fine particles are shifted. When such a shift occurs, there are areas on the inner wall constituting the main body where only the fine particles fall in a concentrated manner, and deposits are likely to form in these areas.

[0007] One possible means of suppressing the generation of such deposits is to provide a rotating structure as described in Patent Document 2. However, providing such a rotating structure would complicate the device configuration, and there is a concern that installation and maintenance work would become complicated.

[0008] In view of this, the present disclosure provides a cement raw material supplying device capable of suppressing adhesion of cement raw materials to an inner wall with a simple device configuration. The present disclosure also provides a cement clinker production facility capable of stably operating by including such a cement raw material supplying device. The present disclosure also provides a cement clinker production method capable of stably producing cement clinker. [Means for solving the problem]

[0009] The present disclosure provides a cement raw material supplying device comprising a main body having an internal space into which cement raw materials fall and configured to be able to store the fallen cement raw materials, an inlet section for introducing the cement raw materials from above the main body, an outlet section for discharging the cement raw materials from below the main body, and a collision member that changes the falling direction of only a portion of the cement raw materials falling in the internal space of the main body by colliding with the portion.

[0010] The cement raw material supply device disclosed herein is equipped with a collision member that changes the falling direction of only a portion of the cement raw material by colliding with the collision member. When the falling direction of only a portion of the cement raw material is changed by the collision member, even if drift occurs in the falling cement raw material, the drift is reduced by the portion, and the uniformity of the particle size distribution of the cement raw material can be improved. This makes it possible to prevent the occurrence of areas where only fine particles fall in a concentrated manner, and to prevent the formation of deposits on the inner walls that form the internal space, with a simple device configuration.

[0011] In the above-mentioned cement raw material supplying device, it is preferable that a part of the cement raw material colliding with the collision member includes coarse particles having a particle size larger than the average particle size of the cement raw material. By changing the falling direction of such coarse particles, it is possible to further prevent deposits from being formed on the inner wall that defines the internal space. Even if deposits are formed on the inner wall, the deposits fall due to the collision of the coarse particles with the deposits, so that it is possible to prevent the deposits from growing and becoming large.

[0012] In the cement raw material supplying device, the introduction direction of the cement raw material when it is introduced into the main body from the introduction part and the discharge direction of the cement raw material in the discharge part may intersect with each other in a plan view. If the introduction direction and the discharge direction intersect with each other, when a phenomenon occurs in which coarse particles and fine particles are drifted, deposits are likely to form on downstream equipment. In the cement raw material supplying device, the drift can be suppressed, so that it is possible to significantly reduce deposits on downstream equipment while ensuring freedom in equipment design, and it is possible to stably supply the cement raw material.

[0013] The cement raw material is a blended raw material containing a plurality of types of raw materials, and it is preferable to provide a raw material mill downstream of the discharge section. Upstream of the raw material mill, there is a large difference in particle size between the coarse particles and the fine particles contained in the cement raw material. For this reason, drift due to the difference in particle size of the particles contained in the cement raw material is likely to occur. Therefore, by providing the main body section and the collision member upstream of the raw material mill, it is possible to suppress the drift phenomenon of the coarse particles and the fine particles even upstream of the raw material mill, and to suppress adhesion of the cement raw material to the inner walls of the facility.

[0014] The cement raw material discharged from the outlet is preferably introduced into the raw material mill through a charging chute. Since the cement raw material discharged from the outlet is prevented from drifting between the coarse particles and the fine particles, adhesion of the fine particles to the charging chute can be prevented. This allows the raw material mill to be operated stably.

[0015] The cement raw material preferably contains two or more raw materials selected from the group consisting of incineration ash, coal ash, limestone, an iron source, and slag. Even if raw materials with different specific gravities are contained in this way, it is possible to suppress uneven flow of coarse particles and fine particles, and to suppress adhesion of the cement raw material to the inner wall.

[0016] It is preferable to drop the re-ground raw material to be ground in the raw material mill into the internal space between the collision member and the inner wall of the main body that faces the collision surface of the collision member. The re-ground raw material is a coarse material that is separated from fine material in the raw material mill, which is a grinding facility. The re-ground raw material has a larger particle size than other cement raw materials. Therefore, by dropping the re-ground raw material into the area where the cement raw material with a smaller particle size falls, it is possible to sufficiently prevent the cement raw material with a smaller particle size from adhering to the inner wall of the main body.

[0017] The present disclosure provides a cement clinker production facility including any one of the above-described cement raw material supplying devices, a raw material mill that pulverizes the cement raw materials supplied from the cement raw material supplying device, and a calcination device that calcines the pulverized cement raw materials to obtain cement clinker. Since the cement clinker production facility includes any one of the above-described cement raw material supplying devices, the cement raw materials can be pulverized stably. Therefore, cement clinker can be stably produced.

[0018] The present disclosure provides a method for producing cement clinker, the method including the steps of: pulverizing a cement raw material supplied from any one of the above-described cement raw material supply devices; and calcining the pulverized cement raw material to obtain cement clinker. Since the method for producing cement clinker uses the cement raw material supplied from any one of the above-described cement raw material supply devices, clogging of the inside of the equipment due to deposits can be suppressed, and cement clinker can be stably produced. Effect of the Invention

[0019] According to the present disclosure, it is possible to provide a cement raw material supplying device capable of suppressing adhesion of cement raw materials to an inner wall with a simple device configuration. In addition, it is possible to provide a cement raw material grinding device and a cement clinker production facility capable of stably operating by including such a cement raw material supplying device. It is also possible to provide a cement clinker production method capable of stably producing cement clinker. [Brief description of the drawings]

[0020] [Figure 1] FIG. 2 is a front view showing the inside of a main body of the cement raw material supply device according to the embodiment. [Diagram 2] FIG. 2 is a plan view of the cement raw material supplying device of FIG. [Diagram 3] FIG. 2 is a cross-sectional view taken along line III-III in FIG. [Figure 4] FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. [Diagram 5] 1 is a diagram showing a schematic diagram of a state in which a part of the cement raw material collides with a collision member and changes its falling direction. FIG. [Figure 6] FIG. 11 is a front view showing the inside of a main body of a cement raw material supplying device according to another embodiment. [Figure 7] FIG. 7 is a plan view of an example of the cement raw material supplying device shown in FIG. [Figure 8] FIG. 11 is a front view showing the inside of a main body of a cement raw material supplying device according to still another embodiment. [Figure 9] FIG. 11 is a front view showing the inside of a main body of a cement raw material supplying device according to still another embodiment. [Figure 10] (A) is a photograph showing an example of the cement raw material discharged at the discharge part of the cement raw material supplying apparatus of Fig. 1. (B) is a photograph showing an example of the cement raw material discharged at the discharge part of the cement raw material supplying apparatus of Fig. 11. (C) is a photograph showing an example of the cement raw material discharged at the discharge part of the cement raw material supplying apparatus of Fig. 12. [Figure 11] FIG. 1 is a diagram showing a conventional cement raw material supply device (comparative example). [Figure 12] FIG. 12 is a diagram showing a modification (comparative example) of the cement raw material supplying device of FIG. [Figure 13] FIG. 1 is a diagram showing an example of a calcination apparatus for calcining cement raw materials. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] Hereinafter, an embodiment of the present invention will be described with reference to the drawings as needed. However, the following embodiment is an example for explaining the present invention, and is not intended to limit the present invention to the following content. In the description, the same reference numerals are used for the same elements or elements having the same functions, and redundant description is omitted as the case may be. Furthermore, positional relationships such as up, down, left, and right are based on the positional relationships shown in the drawings, unless otherwise specified. Furthermore, the dimensional ratios of each element are not limited to those shown in the drawings.

[0022] 1 is a diagram showing the inside of a main body of a cement raw material supplying apparatus according to one embodiment, as viewed from the front. The cement raw material supplying apparatus 100 includes a main body 10 having an internal space 12 into which cement raw material 50 falls and configured to be capable of storing the fallen cement raw material 50, an introduction section 20 for introducing the cement raw material 50 from above the main body 10, an outlet section 30 for discharging the cement raw material 50 from below the main body 10, and a collision member 15A for changing the falling direction of only a portion of the cement raw material 50 falling in the internal space 12 of the main body 10 by colliding with the portion.

[0023] The introduction section 20 transports the cement raw material 50 and introduces the cement raw material 50 into the main body section 10. The introduction section 20 may be, for example, a normal conveying machine such as a belt conveyor. The main body section 10 is, for example, a tank, and has an internal space 12 in which the cement raw material 50 is temporarily stored. The main body section 10 has, at its lower part, a constricted section 10A that becomes narrower from top to bottom. The cement raw material 50 is introduced into the main body section 10 from the introduction section 20 and falls through the internal space 12 of the main body section 10. The cement raw material 50 falling through the internal space 12 is collected by the constricted section 10A at the lower part of the main body section 10, and after being temporarily stored in the main body section 10, it is discharged from an outlet in the center of the bottom of the main body section 10 to a discharge section 30 provided below the main body section 10.

[0024] The discharge section 30 transports the cement raw material 50 discharged from the main body section 10 and introduces the cement raw material 50 into a feed chute 40 of downstream equipment. The discharge section 30 may be, for example, a normal conveying machine such as a belt conveyor. The downstream equipment may be, for example, a raw material mill used in cement production. The discharge section 30 adjusts the amount of cement raw material 50 discharged from the main body section 10 by changing the conveying speed of the cement raw material. When the introduction and discharge amounts of cement raw material 50 are different, the inventory of cement raw material 50 in the internal space 12 of the main body section 10 can be changed to stably continue operation of the cement raw material supplying device.

[0025] The cement raw materials 50 may be various raw materials used in the manufacture of cement. For example, they may be mixed raw materials containing a plurality of types of raw materials having different sizes, or raw materials before mixing. As various raw materials are used for the cement raw materials 50, the range of particle sizes is wide. The cement raw materials 50 also include materials that tend to harden easily, such as CaO. Furthermore, fine particles with small particle sizes among the cement raw materials 50 tend to adhere to the inner walls of equipment, etc., more easily than coarse particles with large particle sizes.

[0026] FIG. 11 is a diagram showing a conventional cement raw material supplying apparatus (comparative example). In the cement raw material supplying apparatus 200, the cement raw material 250 introduced from the introduction section 220 to the main body section 210 falls through the internal space 212. At this time, the coarse particles of the cement raw material 250 fall toward the downstream side (left side in FIG. 11) of the conveying direction of the introduction section 220. On the other hand, the fine particles of the cement raw material 250 fall toward the upstream side (right side in FIG. 11) of the conveying direction of the introduction section 220 more than the coarse particles. Therefore, in the constricted section 210A at the bottom of the main body section 210, only the fine particles fall to the right side in FIG. 11 and adhere to the inner wall, forming an attachment 91. For example, in normal operation, the cement raw material 250 accumulates in the internal space 212, but even if all the cement raw material 250 is discharged, the attachment 91 of the cement raw material 250 remains in the constricted section 210A.

[0027] If deposits 91 remain, it becomes easier for defects to occur in the extraction of the raw materials from the discharge section 230. In addition, fine particles that fall unevenly toward the upstream side of the conveying direction of the introduction section 220 (the right side in FIG. 11) can also cause deposits 92 on the input chute 240. If such deposits 92 occur, the input chute 240 will also be unable to normally supply the cement raw materials. If the input chute 240 becomes clogged, it will be necessary to stop operation of the cement raw material supply device 200 and clean the inside, etc.

[0028] FIG. 12 is a diagram showing a modified example (comparative example) of the cement raw material supplying device of FIG. 11. The cement raw material supplying device 201 is provided inside the main body 210 with a collision member 215 that changes the falling direction of all the cement raw materials 250 by colliding with all the cement raw materials 250 falling in the internal space 212. In this case, the falling direction of the coarse particles of the cement raw materials 250 is greatly changed by the collision member 215, and the coarse particles fall biased toward the upstream side of the introduction section 220 in the conveying direction (the right side in FIG. 12). On the other hand, some of the fine particles of the cement raw materials 250 fall along the collision member 215, and such fine particles fall biased toward the downstream side of the introduction section 220 in the conveying direction (the left side in FIG. 12). Therefore, in the constriction section 210A at the bottom of the main body 210, only the fine particles fall and adhere to the left side in FIG. 12, forming an adhesion 93. In this case as well, even if the cement raw material 250 is temporarily stored in the internal space 212 and then all of the cement raw material 250 is discharged, the deposits 93 of the cement raw material 250 remain on the constricted portion 210A.

[0029] If deposits 93 remain, the raw material is easily discharged from the discharge part 230 with poor results. In addition, fine particles are unevenly discharged from the discharge part 230, so deposits 94 form in the input chute 240 of the downstream equipment. If deposits 94 form, the input chute 240 is easily clogged. For this reason, it becomes necessary to stop the operation of the cement raw material supplying device 201 and clean the inside, etc.

[0030] On the other hand, as shown in Fig. 1, the cement raw material supplying device 100 is provided with a collision member 15A against which only a portion of the cement raw material 50 collides. When the falling direction of only a portion of the cement raw material is changed by the collision member 15A, the deviation in particle size is reduced by the portion, and the uniformity of the particle size distribution of the falling cement raw material 50 can be improved. This prevents the occurrence of a portion in which only fine particles fall in a concentrated manner in the constricted section 10A, and prevents the formation of deposits on the inner wall 10a that defines the internal space 12. Also, the formation of deposits on the input chute 40 can be prevented.

[0031] The cement raw material 50 may contain two or more kinds selected from the group consisting of incineration ash, coal ash, limestone, an iron source, and slag. The above raw materials have different particle sizes and contain CaO, so that they tend to solidify. Since the cement raw material supplying device 100 has the collision member 15A, even if the cement raw material 50 contains CaO, the deviation in particle size of the cement raw material 50 is reduced, so that the cement raw material 50 can be sufficiently prevented from adhering to the inner wall 10a constituting the internal space 12.

[0032] Fig. 2 is a view of the cement raw material supplying device of Fig. 1 as viewed from above the introduction part. The collision member 15A may be a part of the frame 15. The frame 15 may be fixed to the inner wall 10a of the main body 10 by a support part (not shown), or may be fixed to a lid member provided so as to cover the upper surface of the main body 10. Such a lid member has an introduction port through which the cement raw material 50 from the introduction part 20 can pass.

[0033] In a plan view (xy plane) as shown in FIG. 2, the introduction direction (C1 direction) of the cement raw material when it is introduced from the introduction section 20 to the main body section 10 and the discharge direction (C2 direction) of the cement raw material in the discharge section 30 may cross. If the C1 direction and the C2 direction cross each other, when the phenomenon of the coarse particles and the fine particles being biased occurs, deposits are likely to be formed on the downstream equipment. For example, in FIG. 1, when the fine particles fall biasedly to the right side of the main body section 10, in FIG. 2, the cement raw material discharged from the discharge outlet 18 provided at the lower stage of the main body section 10 to the discharge section 30 is conveyed with the fine particles biased to the right side of FIG. 2. In this case, the fine particles are also supplied to the input chute 40 of the downstream equipment with the fine particles biased to the right side.

[0034] In this embodiment, since the uneven distribution of the coarse and fine particles in the cement raw material 50 can be suppressed, even if the C1 direction and the C2 direction cross each other, the formation of deposits on the downstream equipment can be sufficiently suppressed. In this embodiment, the C1 direction and the C2 direction are perpendicular to each other, but are not limited to this. For example, the C1 direction in FIG. 2 may be shifted from the x direction. For example, the C2 direction in FIG. 2 may be shifted from the y direction. In this way, since the C1 direction and the C2 direction can be set in various directions, the degree of freedom in equipment design can be sufficiently ensured.

[0035] 3 is a cross-sectional view taken along line III-III in FIG. 1, and FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. 1. In FIG. 3, the frame 15 has a rectangular tubular cross-sectional shape. In FIG. 4, which shows a cross-sectional structure below FIG. 3, only the cross-sectional structure of the collision member 15A of the frame 15 is shown. In this manner, the collision member 15A forming a part of the rectangular tubular frame 15 is longer in the vertical direction than the other part 15B of the frame 15. A part of the cement raw material 50 falling through the internal space 12 may collide with this longer part. The collision member 15A may be configured so that its length along the vertical direction is adjustable. For example, the collision member 15A may be configured by overlapping two plates, and the length in the xy plane may be adjusted by moving one plate relative to the other plate. Thereby, the ratio of the cement raw material 50 colliding with the collision member 15A may be changed by adjusting the length of the collision member 15A relative to the other portion 15B depending on the particle size distribution of the cement raw material 50 and the adhesion state of the cement raw material 50 on the inner wall 10a.

[0036] 5 is a schematic diagram showing how a portion of the cement raw material 50 collides with the collision member 15A and changes its falling direction. A portion 52 of the cement raw material 50 collides with the collision surface 16 of the collision member 15A and changes its falling direction from diagonally downward left to diagonally downward right. Meanwhile, a portion 51 of the cement raw material 50 falls diagonally downward left without colliding with the collision member 15A. In this way, the change in the falling direction of the portion 52 suppresses bias in the particle size of the falling cement raw material.

[0037] Collision member 15A is made of a steel plate and is fixed at an incline so that the collision surface faces upward. This makes it possible to significantly change the falling direction of part 52 of the colliding cement raw material 50. This makes it possible to sufficiently suppress unevenness in the particle size of the falling cement raw material 50 and further improve the uniformity of the particle size distribution of the cement raw material 50 at the falling position. However, the collision surface does not necessarily have to face upward. For example, even if the collision surface of the collision member is parallel to the vertical direction, it is possible to change the falling direction of part 52 of the cement raw material 50 and suppress unevenness in the particle size.

[0038] In this embodiment, the collision member 15A constitutes a part of the frame 15, but is not limited thereto. For example, the collision member 15A may be constituted by a flat plate, and this flat plate may be fixed to the inner wall 10a of the main body 10 or to a lid covering the upper part of the main body 10. In addition, the collision member 15A may have a notch formed in the center of the lower end, and may have a concave shape. The size of this notch may be changed to adjust the proportion of the part 52 of the cement raw material 50 that collides with the collision member 15A. By providing the notch in the center, wear of the collision member 15A can be suppressed.

[0039] It is preferable that the portion 52 of the cement raw material 50 colliding with the collision member 15A contains coarse particles having a particle size larger than the average particle size of the entire cement raw material 50. By changing the falling direction of the coarse particles, it is possible to further prevent deposits from being formed on the inner wall 10a that defines the internal space 12. Even if deposits are formed on the inner wall 10a, the deposits fall due to the collision of the coarse particles with the deposits, and therefore it is possible to prevent the deposits from growing larger.

[0040] The average particle size of the entire cement raw material 50 is determined, for example, by randomly selecting 100 or more particles and measuring the diameter of the circumscribed circle circumscribing the outer edge of the particles in a two-dimensional image. The average particle size is calculated as the number average value of the particle sizes measured in this manner. Note that the particle size may be measured using an optical microscope or a scanning electron microscope as necessary.

[0041] Fig. 6 is a front view showing the inside of the main body of a cement raw material supplying apparatus according to another embodiment. The cement raw material supplying apparatus 101 in Fig. 6 differs from the above-mentioned cement raw material supplying apparatus 100 in that it has a second introduction section 22 in addition to the introduction section 20 (first introduction section) and has a collision member 15A' composed of two plate-like members 15a and 15d. The other configurations may be similar to those of the cement raw material supplying apparatus 100.

[0042] From the second introduction section 22, for example, re-ground raw material 55 of the raw material mill is introduced. The re-ground raw material 55 is a coarse material that was fed into the raw material mill but was not sufficiently ground, and is re-ground in the raw material mill. The raw material mill is a device that performs grinding and classification after all cement raw materials that need to be ground are mixed, and the ground material (fine material) obtained in the raw material mill is supplied to a burning device described later. On the other hand, the re-ground raw material 55, which has a particle size larger than that of the ground material, falls through the internal space 12 between the collision member 15A' and the inner wall 10b of the main body 10 facing the collision surface of the collision member 15A'. Since the re-ground raw material 55 has a particle size larger than that of the fine material contained in the cement raw material 50, even if the fine material of the cement raw material 50 falls unevenly into the internal space 12 between the collision surface of the collision member 15A' and the inner wall 10b of the main body 10 facing the collision surface of the collision member 15A', the re-ground raw material 55 can prevent the fine material from adhering to the right side of the constriction section 10A.

[0043] The amount of re-ground raw material 55 introduced may vary depending on the operation of the raw material mill. For this reason, the size of the collision surface of the collision member 15A' may be adjusted according to the change in the amount of re-ground raw material 55 introduced. The size of the collision surface can be adjusted by changing the ratio of the overlapping portion and the non-overlapping portion of the two plate-like members 15a, 15d that are provided so as to overlap each other.

[0044] Fig. 7 is an example of a plan view of the cement raw material supplying device 101 shown in Fig. 6. As shown in Fig. 7, the introduction direction of the cement raw material in the first introduction section 20 (direction C1) and the introduction direction of the re-ground raw material in the second introduction section 22 (direction C3) may be opposite to each other. In this way, when the fine particles of the cement raw material fall unevenly in the direction opposite to the C1 direction through the internal space 12 of the main body 10, the unevenness of the fine particles and their adhesion to the inner wall can be eliminated by introducing the re-ground raw material from the second introduction section 22 that conveys the re-ground raw material in the C3 direction.

[0045] In this embodiment, the C1 direction and the C3 direction are oriented in opposite directions, but are not limited thereto. For example, the C1 direction in FIG. 7 may be offset from the x direction. For example, the C3 direction in FIG. 7 may be offset from the opposite direction to the x direction. In this manner, the C1 direction and the C3 direction can be set in various directions. As shown in FIG. 7, the first introduction section 20 and the second introduction section 22 may be provided so as to be offset in the up-down direction in FIG. 7.

[0046] Fig. 8 is a front view showing the inside of the main body of a cement raw material supplying apparatus according to still another embodiment. The cement raw material supplying apparatus 102 in Fig. 8 differs from the above-mentioned cement raw material supplying apparatus 100 in that it is provided with a third introduction section 24 for introducing re-ground raw material 57 ground in the raw material mill. The other configurations may be the same as those of the cement raw material supplying apparatus 100.

[0047] The third introduction section 24 is disposed on the main body 10, shifted to the left of the second introduction section 22 shown in FIG. 6. Therefore, the re-ground raw material 57 introduced from the third introduction section 24 into the internal space 12 slides on the collision surface of the collision member 15A and falls. By dropping the re-ground raw material 57 in this manner, the amount and speed of collision of the cement raw material 50 with the collision member 15A can be reduced. This reduces wear on the collision member 15A. The re-ground raw material 57 can be the same as the re-ground raw material 55.

[0048] In a modified example of the cement raw material supplying apparatus 102, the cement raw material 50 may be introduced from the third introduction part 24. In this manner, the same raw material may be introduced from two introduction parts. In another modified example, the collision member 15A' of Figs. 6 and 7 may be provided instead of the collision member 15A.

[0049] Fig. 9 is a front view showing the inside of a main body of a cement raw material supplying apparatus according to still another embodiment. The cement raw material supplying apparatus 103 in Fig. 9 includes a collision member 15C instead of the collision member 15A of the cement raw material supplying apparatus 100 in Fig. 1. Other parts may be similar to those of the cement raw material supplying apparatus 100.

[0050] The collision member 15C has a hook portion 15f formed at its lower end. A part of the cement raw material 50 that collides with the collision member 15C is deposited on this hook portion 15f. In FIG. 9, the cement raw material deposited on the hook portion 15f is shown as white particles. When the cement raw material 50 is deposited on the hook portion 15f of the collision member 15C, a part of the cement raw material 50 subsequently collides with the deposit on the hook portion 15f. This makes it possible to suppress wear of the collision member. The deposit on the hook portion 15f may adhere to the collision member 15C.

[0051] In a modified example of the cement raw material supplying device 103, a second introduction part 22 as shown in Fig. 6 may be provided to introduce re-ground raw material 55 into the main body 10, or a third introduction part 24 as shown in Fig. 8 may be provided to introduce re-ground raw material 57. In this case, at least a part of the deposit on the hook part 15f may be the re-ground raw material 57.

[0052] FIG. 10(A) is a photograph showing an example of cement raw materials discharged at the discharge section 30 of the cement raw material supplying apparatus 100 in FIG. 1. FIG. 10(A) shows how the cement raw materials are conveyed by the conveyor of the discharge section 30 from top to bottom of the photograph. In FIG. 10(A), the deviation in particle size of the cement raw materials is sufficiently reduced. The cement raw material supplying apparatuses 101, 102, and 103 can also sufficiently reduce the deviation in particle size of the cement raw materials. In this way, the cement raw material supplying apparatuses 100, 101, 102, and 103 can improve the uniformity of the particle size distribution of the circulating cement raw materials. This makes it possible to suppress the occurrence of areas where only fine particles are concentrated and fall, and to suppress the formation of deposits on the inner wall 10a constituting the internal space 12 and the inner wall of the downstream input chute 40.

[0053] Fig. 10(B) is a photograph showing an example of cement raw materials discharged at discharge section 230 of cement raw material supplying apparatus 200 in Fig. 11. Fig. 10(B) also shows how cement raw materials are transported from the top to the bottom of the photograph by the conveyor of discharge section 230. In Fig. 10(B), coarse particles are biased toward the left side of the photograph. In this case, as shown in Fig. 11, fine particles adhere to the right side of main body section 210 and the right side of input chute 240, forming deposits 91, 92.

[0054] Fig. 10(C) is a photograph showing an example of cement raw materials discharged at discharge section 230 of cement raw material supplying apparatus 201 in Fig. 12. Fig. 10(C) also shows how cement raw materials are transported by the conveyor of discharge section 230 from the top to the bottom of the photograph. In Fig. 10(C), coarse particles are biased toward the right side of the photograph. For this reason, as shown in Fig. 12, fine particles adhere to the left side of main body section 210 and the left side of input chute 240, forming deposits 93, 94.

[0055] A cement clinker manufacturing facility according to one embodiment includes any one of the above-described cement raw material supplying devices 100, 101, 102, 103 or a modified version thereof, a grinding device that grinds the cement raw material supplied from the cement raw material supplying device, and a firing device that fires the cement raw material ground by the grinding device.

[0056] FIG. 13 is a diagram showing an example of a calcination apparatus for calcining cement raw materials. The cement raw materials discharged from the discharge section 30 of the cement raw material supplying apparatus 100 (101, 102, 103) are crushed in a raw material mill via a charge chute 40, for example. The cement raw materials crushed in the raw material mill and classified as necessary are introduced into a calcination apparatus 150 including an introduction section 151 for preheating and calcining the cement raw materials, a kiln 152 for calcining the preheated and calcined cement raw materials to obtain cement clinker, and a clinker cooler 153 for cooling the cement clinker obtained in the kiln 152. The introduction section 151 has four cyclones C1, C2, C3, C4 (preheaters) and a calciner 112.

[0057] The kiln end 122 of the kiln 152 and the calciner 112 of the introduction section 151 are connected by a rising duct 114. A probe 142 is connected to the rising duct 114, which extracts the exhaust gas in the rising duct 114 and introduces the extracted gas into the chlorine bypass 140.

[0058] The chlorine bypass 140 has, in this order from the probe 142 side, a cooling section 143 for cooling the bleed gas, a chamber 145, a heat exchanger 146, a dust collector 147, and a suction fan 148. The bleed gas is cooled to a temperature equal to or lower than the melting point of the volatile alkali salt by the cooling section 143 and the heat exchanger 146. Clinker dust contained in the bleed gas and precipitated as a result of cooling is collected by the dust collector 147. The exhaust gas discharged from the suction fan 148 may be introduced into a clinker cooler 153, for example, as a cooling gas for cement clinker. By providing the chlorine bypass 140, the volatile components in the calcination device 150 can be reduced.

[0059] The cement raw materials introduced from the connection part between cyclones C1 and C2 in the introduction part 151 flow through cyclones C1, C2, C3, the rising duct 114, the calciner 112, and C4, and reach the kiln end 122 of the kiln 152. In the kiln 152, the preheated and calcined cement raw materials are heated by combustion of the burner 124 provided on the rear end side of the main body 126, and become cement clinker. The obtained cement clinker is cooled in the clinker cooler 153. After being cooled in the clinker cooler 153, cement clinker is obtained.

[0060] In this way, a cement clinker production facility equipped with any one of the cement raw material supply devices 100, 101, 102, and 103 or a modified example thereof can suppress clogging of the inside of the facility due to deposits. Therefore, the cement raw material introduced into the introduction part 151 can be stably produced, and the cement clinker production facility can be stably operated. As a result, cement clinker can be stably produced.

[0061] A method for producing cement clinker according to an embodiment includes a step of crushing the cement raw material supplied from a cement raw material supplying device, and a step of burning the crushed cement raw material to obtain cement clinker. The method for producing cement clinker may use any one of the cement raw material supplying devices 100, 101, 102, and 103, or a modified version thereof. In the above step, the cement raw material supplied from the cement raw material supplying device is crushed, and the crushed cement raw material is supplied to a burning device 150 as shown in FIG. 13 to burn the cement raw material to obtain cement clinker. In this production method, the cement raw material supplied from any one of the cement raw material supplying devices 100, 101, 102, and 103, or a modified version thereof, is used, so that clogging of the inside of the equipment due to deposits can be suppressed. Therefore, it is possible to stably produce the cement raw material, and the cement clinker can be stably produced.

[0062] Although the embodiment of the present invention has been described above, the present invention is not limited to the above embodiment. For example, the cement raw material discharged from the discharge section 30 may pass through equipment such as a seal hopper, a roll feeder, and a three-stage gate before passing through the input chute 40. Even in such equipment, the generation of adhesion can be suppressed. The discharge section 30 may be a roll feeder.

[0063] In addition, in some examples, the cement raw materials after all raw material blending is completed, that is, the cement raw materials fed into the raw material mill are described, but the present invention is not limited thereto. For example, the cement raw materials may be those before the raw material blending is completed. For example, the present invention can be applied to a case where two or more types of cement raw materials having significantly different particle sizes (for example, two types selected from incineration ash, coal ash, limestone, iron source, and slag) are introduced into the main body from one belt conveyor. In this case, too, by providing a collision member in the main body as in each of the above embodiments and changing the falling direction of only a part of the cement raw materials falling in the internal space of the main body, it is possible to suppress the bias in particle size and improve the uniformity of the particle size distribution of the cement raw materials. This makes it possible to suppress the formation of deposits on the inner walls of the equipment with a simple device configuration. In addition, it is possible to suppress the occurrence of poor extraction of the cement raw materials. [Explanation of symbols]

[0064] 10,210...Main body, 10A,210A...Throttling section, 10a,10b...Inner wall, 12,212...Internal space, 15...Frame, 15A,15A',15C,215...Collision member, 15a,15d...Plate-shaped member, 15f...Hook section, 16...Collision surface, 18...Outlet, 20...Introduction section (first introduction section), 22...Second introduction section, 24...Third introduction section, 220...Introduction section, 30,230...Outlet, 40,240...Feeding chute, 50,250...Cement raw material, 55,57...Re-ground raw material, 91,92, 93, 94...deposits, 100, 101, 102, 103, 200, 201...cement raw material supply device, 112...calciner, 114...rising duct, 122...kiln bottom, 124...burner, 126...main body, 140...chlorine bypass, 142...probe, 143...cooling section, 145...chamber, 146...heat exchanger, 147...dust collector, 148...suction fan, 150...calciner, 151...introduction section, 152...kiln, 153...clinker cooler, C1, C2, C3, C4...cyclone.

Claims

1. a main body having an internal space into which the cement raw material falls and configured to store the fallen cement raw material; An introduction portion for introducing the cement raw material from above the main body portion; A discharge portion that discharges the cement raw material from below the main body portion; A frame body having a rectangular cylindrical horizontal cross-sectional shape fixed to an inner wall of the main body portion; a plate-shaped collision member that forms a part of the frame and extends vertically downward beyond the other part of the frame, the collision member has a collision surface facing an introduction direction C1 of the cement raw material in the introduction portion in a plan view, and changing a falling direction of the cement raw material when the cement raw material falls through the internal space of the main body and collides with the collision surface, A method for supplying cement raw materials, comprising the steps of: causing only a portion of the cement raw material falling through the internal space to collide with the collision surface, thereby changing the falling direction of only that portion.

2. 2. The method for supplying a cement raw material according to claim 1, wherein the portion of the cement raw material colliding with the collision surface includes coarse particles having a particle size larger than an average particle size of the cement raw material.

3. A method of supplying cement raw materials as described in claim 1 or 2, wherein the introduction section transports the cement raw materials along the introduction direction C1 in a planar view by a conveying machine.

4. 3. The method for supplying a cement raw material according to claim 1, wherein an introduction direction C1 of the cement raw material when being introduced from the introduction portion to the main body portion and a discharge direction of the cement raw material in the discharge portion intersect with each other in a plan view.

5. The method for supplying a cement raw material according to any one of claims 1 to 4, wherein the cement raw material is a mixed raw material containing a plurality of types of raw materials.

6. The method for supplying a cement raw material according to any one of claims 1 to 5, wherein the cement raw material comprises two or more selected from the group consisting of incineration ash, coal ash, limestone, an iron source, and slag.

7. A method for producing cement clinker, comprising: a step of crushing the cement raw material supplied from the cement raw material supply device by the cement raw material supply method according to any one of claims 1 to 6; and a step of burning the crushed cement raw material to obtain cement clinker.

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