Device and method of producing refractory raw material, and device of separating surface layer deposit

Abstract

To provide a technique of producing a refractory raw material, capable of effectively separating / removing a surface layer deposit, while maintaining the yield of a refractory block.SOLUTION: The present invention provides a device for producing a refractory raw material by separating / removing a surface layer deposit from a refractory block having a deposit layer on its surface, the device being configured to include a high-speed agitation mixer comprising a cylindrical body provided with sieve holes and rotating on a symmetric axis as a rotation axis, and a rotary tool having a rotation axis positioned differently from the rotation axis of the cylindrical body and rotating independently of the cylindrical body, wherein the rotary tool includes ropes or chains fixed to the rotation axis and strikers fixed to the rotation axis, and wherein the refractory block charged into a charging port of the cylindrical body has its surface layer deposit separated and removed as undersize, and the remaining portion is recovered as a refractory raw material from a discharge port of the cylindrical body. The present invention also provides a method of producing a refractory raw material using the device, wherein the number of rotations of the cylindrical body is set to 10 to 60 Hz and the number of rotations of the rotary tool is set to 30 to 80 Hz or less.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an apparatus and method for producing a raw refractory material, which separates and removes surface deposits from used refractory material and regenerates it as a raw refractory material, and a surface deposit separator. In this specification, the term "x to y" defining a numerical range means not less than x and not more than y, and includes the boundary value. [Background technology]

[0002] In recent years, as part of efforts to improve recycling efficiency in the steel industry, it has been proposed to reuse refractory bricks used in the iron and steelmaking process. Refractory bricks include torpedo bricks and converter bricks. In general, the working surfaces of refractory bricks, such as the surfaces that come into contact with molten steel, molten iron, and slag, have iron and slag adhering to the surface through the iron and slag that have penetrated into the pores in the refractory. In addition, some other surfaces may have mortar used during construction adhering to them. When recycling such refractory bricks, if the above-mentioned adhering materials are mixed in, the durability of the recycled product as a refractory material will be significantly reduced and it will no longer be usable. Therefore, when recycling refractory bricks, it is necessary to remove the surface adhering materials such as slag.

[0003] In the conventional method for recycling used refractory bricks, the slag adhering to the surface of each refractory brick is separated by manual striking, and then the refractory bricks are crushed to obtain refractory raw materials. This method allows only a portion of the used refractory bricks to be reused, and is not fully satisfactory in terms of work efficiency and running costs. Therefore, in order to efficiently recycle refractory bricks, it is desired to automate the separation of slag and other adhering matter from the surface of refractory bricks in large quantities.

[0004] In response to this, for example, Patent Document 1 discloses a method for regulating the particle size of granulated blast furnace slag, in which granulated blast furnace slag is charged into a high-speed agitating mixer and agitated to change at least the particle size distribution of the granulated blast furnace slag. This high-speed agitating mixer includes a rotating mixing pan, a mixing tool that is arranged eccentrically from the center of the mixing pan and rotates independently of the mixing pan, and a scraper that is fixedly arranged inside the mixing pan. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2006-21942 A Summary of the Invention [Problem to be solved by the invention]

[0006] However, the above-mentioned conventional techniques have the following problems to be solved. That is, when the sizing work was performed manually, it was not satisfactory in terms of work efficiency, running costs, etc. Also, when the sizing device proposed in Patent Document 1 was used, there were problems such as the remaining slag being observed, which did not improve the refractory purity very much, and the refractory block, which is the base material, being lower in hardness than the adhering slag, which resulted in a large amount of chipping of the refractory block, which reduced the yield.

[0007] Therefore, in order to solve the above-mentioned problems associated with the conventional technology, the present invention aims to provide an apparatus and method for manufacturing a refractory raw material, and an apparatus for separating surface deposits, which are capable of effectively separating and removing surface deposits from a refractory block having an adhesion layer on its surface while ensuring the yield of the refractory block. [Means for solving the problem]

[0008] In the course of studying the above-mentioned problems associated with the conventional techniques, the inventors discovered that by applying a soft whip-like strike such as a chain or wire instead of a rigid body such as a hammer, it is possible to efficiently peel off the surface deposits of the refractory block, and thus completed the present invention.

[0009] That is, the manufacturing apparatus for refractory raw material according to the present invention, which advantageously solves the above-mentioned problems, is an apparatus for producing a refractory raw material by separating and removing surface deposits from a refractory lump having an adhesion layer on its surface, and is characterized in that it is equipped with a high-speed stirring mixer having a cylinder having sieve holes and rotating about an axis of symmetry, and a rotating tool having a rotation axis at a position different from the rotation axis of the cylinder and rotating independently of the cylinder, the rotating tool having a cord or chain fixed to the rotation axis and a striking element fixed to the rotation axis, the refractory lump is charged into the charging port of the cylinder, and the surface deposits are separated and removed as undersize, and the remainder is recovered from the discharge port of the cylinder as a refractory raw material.

[0010] The apparatus for producing a refractory raw material according to the present invention comprises: a. The rotating tool has a cable or a chain extending from the charging port side of the refractory block to a range of 40 to 70% of the axial length of the cylindrical body, and has a striking piece extending from the discharge port side of the refractory raw material to the remaining range of the axial length of the cylindrical body, and the cable or the chain and the striking piece are installed at one or more locations in the circumferential direction of the rotating shaft; b. The sieve holes formed in the cylindrical body have a rectangular or square shape with a side length or a circle equivalent diameter in the range of 15 to 25 mm; c. The rotation axis of the rotary tool is configured to be closer to the rotation axis of the cylinder at the inlet side of the cylinder and farther from the rotation axis of the cylinder at the outlet side of the cylinder; the ends of the cords and the chains are configured to have a gap in the range of more than 0 mm and not more than 150 mm when they are closest to the inner surface of the cylindrical body, and the end of the striker is configured to have a gap in the range of more than 0 mm and not more than 50 mm when they are closest to the inner surface of the cylindrical body; This is a more preferable means of solving the problem.

[0011] Further, the present invention provides a method for producing a refractory raw material which advantageously solves the above-mentioned problems, comprising: using any one of the above-mentioned apparatuses for producing a refractory raw material to separate and remove surface deposits from a refractory block having an adhesion layer on its surface; the method is characterized in that the rotational speed of the cylindrical body is set to 10 to 60 Hz; and the rotational speed of the rotating tool is set to 30 to 80 Hz or less.

[0012] The surface layer deposit separation device of the present invention, which advantageously solves the above-mentioned problems, is a device for separating and removing surface layer deposits from a refractory block having an adhesion layer on its surface, and is characterized in that it is equipped with a high-speed stirring mixer having a cylinder having sieve holes and rotating about its axis of symmetry, and a rotating tool having a rotation axis at a different position from the rotation axis of the cylinder and rotating independently of the cylinder, the rotating tool having a cord or chain fixed to the rotation axis and a striking element fixed to the rotation axis, the refractory block being charged into the charging port of the cylinder, the surface layer deposits being separated and removed as undersize, and the remainder being recovered from the discharge port of the cylinder as refractory raw material.

[0013] The surface deposit separation device according to the present invention is a. The rotating tool has a cable or a chain extending from the charging port side of the refractory block to a range of 40 to 70% of the axial length of the cylindrical body, and has a striking piece extending from the discharge port side of the refractory raw material to the remaining range of the axial length of the cylindrical body, and the cable or the chain and the striking piece are installed at one or more locations in the circumferential direction of the rotating shaft; b. The sieve holes formed in the cylindrical body have a rectangular or square shape with a side length or a circle equivalent diameter in the range of 15 to 25 mm; c. The rotation axis of the rotary tool is configured to be closer to the rotation axis of the cylinder at the inlet side of the cylinder and farther from the rotation axis of the cylinder at the outlet side of the cylinder; the ends of the cords and the chains are configured to have a gap in the range of more than 0 mm and not more than 150 mm when they are closest to the inner surface of the cylindrical body, and the end of the striker is configured to have a gap in the range of more than 0 mm and not more than 50 mm when they are closest to the inner surface of the cylindrical body; This is a more preferable means of solving the problem. Effect of the Invention

[0014] According to the present invention, the used refractory block fed into the device is first struck by a cable or chain. Since the cable or chain itself is flexible and deformable, a shear load in the direction of the tool's rotation acts only on the surface deposits of the refractory block, making the surface deposits easy to peel off from the refractory block. Then, a striking process with a hammer and a clamping process with a cylindrical drum and hammer are performed, so that the surface deposits that are easy to peel off can be efficiently separated and removed, while high-purity refractory raw material can be recovered with a good yield. [Brief description of the drawings]

[0015] [Figure 1] FIG. 1 is a schematic cross-sectional side view illustrating a method for producing a refractory raw material according to one embodiment of the present invention. [Diagram 2] FIG. 1 is a schematic three-dimensional view illustrating a high-speed stirring mixer used in the manufacturing apparatus for a refractory raw material used in the above embodiment, in which (a) is a see-through top view, (b) is a see-through side view, and (c) is a schematic front view. [Diagram 3] FIG. 4 is a conceptual diagram illustrating an impact mechanism using a chain according to the embodiment. [Figure 4] Graph (a) is a graph showing the relationship between the drum rotation speed and the refractory yield and refractory purity, and graph (b) is a graph showing the relationship between the rotating tool rotation speed and the refractory yield and refractory purity. [Diagram 5] 1 is a graph showing the relationship between the chain attachment range and the refractory yield and refractory purity. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] The following is a detailed description of the embodiments of the present invention. The following embodiments are intended to exemplify devices and methods for embodying the technical ideas of the present invention, and are not intended to limit the configuration to those described below. In other words, the technical ideas of the present invention can be modified in various ways within the technical scope described in the claims.

[0017] Fig. 1 is a side cross-sectional view for explaining a method for producing a refractory raw material from a used refractory by using the apparatus for producing a refractory raw material according to the present embodiment. Fig. 2 is a three-sided schematic diagram for explaining a high-speed stirring mixer used in the apparatus for producing a refractory raw material, in which (a) is a see-through top view, (b) is a see-through side view, and (c) is a schematic front view.

[0018] Slag and mortar are attached to the surface of the used refractory block 1 as surface layer deposits 2. The manufacturing apparatus 100 for a refractory raw material according to this embodiment includes a high-speed stirring mixer 101. The high-speed stirring mixer 101 includes a cylindrical drum 10 and a rotating tool 9. The drum 10 rotates around the axis of symmetry of the cylinder as the axis of rotation. In the example of Figs. 1 and 2, the rotating tool 9 includes a rotating shaft 9A, a chain 7 attached to the rotating shaft 9A, and a hammer 8 as a striking element. The chain 7 may be a cord such as a wire, as long as it is capable of flexibly deforming to strike the surface of the refractory block 1 with a soft whip-like strike.

[0019] In the manufacturing apparatus 100 for refractory raw material according to the present embodiment, the refractory block used for nesting is charged into the charging port of the drum 10. Then, a soft whip-like striking process is performed in which the surface deposit 2, such as slag, adhering to the surface of the refractory block 1 is struck by a chain 7 or the like, so that the surface deposit is easily removed. Next, the refractory block 1 undergoes a rigid body striking process using a hammer 8, which is a rigid body, a narrow pressure process using a narrow pressure 5 between the hammer 8 and the inner surface of the drum 10, and a separation process in which the surface deposit 2 that has been removed from the sieve holes provided in the drum 10 is removed as undersize 6. Finally, the refractory raw material 1A from which the surface deposit 2 has been removed is taken out from the discharge port of the drum 10. The manufacturing apparatus 100 for refractory raw material according to the present embodiment also functions as a device for separating surface deposits from the refractory block.

[0020] FIG. 1 is a schematic cross-sectional side view illustrating a method for producing a refractory raw material using a manufacturing apparatus 100 for producing a refractory raw material according to this embodiment. Each step will be described in detail below. The surface layer deposit 2 of the used refractory 1 will be described as slag. In addition, the cord or chain will be described as a chain 7.

[0021] (Soft whip-like impact process) In the chain installation range 3 of the rotary tool 9, as shown in FIG. 1, a soft whip-like impact is applied to the refractory block 1 to which the slag 2 is attached in the front half of the device. The soft whip-like impact process performed in the chain installation range 3 is performed to facilitate the detachment of the slag 2 from the refractory block 1 in the subsequent rigid body impact process and narrow pressure process performed in the hammer installation range 4. In the soft whip-like impact process, as shown in FIG. 3, a linear impact on the surface of the refractory block 1 and sliding of the chain in the rotation direction have the effect of applying a shear load to the interface between the attached slag 2 and the refractory. This effect facilitates the detachment of the slag 2 from the refractory. In the soft whip-like impact process, it is preferable to apply multiple impacts within the chain installation range 3, since this makes it easier for the surface-adhering slag 2 to be detached from the refractory. As a specific method, as shown in FIG. 2, in the chain installation range 3 of the rotary tool 9, it is preferable to configure the chain 7 so that when the tip of the chain 7 is closest to the inner surface of the drum 10, there is a gap in the range of more than 0 mm and not more than 150 mm. For example, when the inner diameter of the drum 10 is 7000 mm, it is preferable that the length from the center of the rotation axis of the rotating tool 9 to the end of the chain 7 is 3350 mm or more and less than 3500 mm, assuming that the rotation axis of the drum and the rotation axis 9A of the rotating tool 9 are almost aligned at the inlet side of the refractory block 1 into the drum 10. If the length of the chain 7 is too short, the impact on the surface of the refractory block 1 becomes too small or no impact can be given. On the other hand, if the length of the chain 7 is too long, the inner surface of the drum 10 will be struck, which may cause problems in terms of the durability of the equipment. In addition, from the viewpoint of the processing efficiency of the refractory raw material, it is preferable that the chains 7 are provided in three or more directions in a rotationally symmetrical manner around the circumferential direction of the rotating tool 9. By arranging them in a rotationally symmetrical manner, the rotating tool 9 can be rotated smoothly. In addition, it is preferable that the chains 7 are provided at intervals of 500 mm or less in the axial direction of the rotating tool. Although there is no lower limit to the interval, it is preferable that the interval is larger than the expected diameter of the chain 7. In addition, the rotating shaft 9A of the rotating tool 9 becomes eccentric and approaches the inner surface of the drum 10 as it approaches the discharge port of the drum 10. Therefore, it is preferable to shorten the length of the chain 7 as it approaches the discharge port from the loading port of the drum 10. For example, the material of the chain 7 may be SS400 or stainless steel.The wire diameter of the chain 7 can be set to 6.5 mm, the outer length to 50 mm, and the outer width to 23 mm. In this case, the mass of the chain 7 is about 0.906 kg per meter.

[0022] (Rigid body impact process) Next, in the hammer installation range 4 of the rotary tool 9, as shown in FIG. 1, the refractory block 1 with the slag after the soft whip-like impact process is subjected to rigid impact by the hammer 8. In this rigid impact process, the surface layer slag 2 is peeled off from the refractory block 1 by impact with the hammer 8. The hammer 8 is preferably of a plate-like structure. The inclination of the impact surface of the hammer 8 with respect to the rotation axis 9A of the rotary tool 9 is preferably such that the refractory block 1 is carried toward the discharge port by the rotation of the hammer 8. In addition, it is preferable to provide a protrusion on the impact surface. The size of the hammer 8 is not particularly limited, but it is preferable that the hammer 8 is configured to have a gap of more than 0 mm and not more than 50 mm when the tip of the hammer 8 is closest to the inner surface of the drum 10. If the hammer 8 comes into contact with the inner surface of the drum, the rotary tool may not be able to rotate, or this may cause problems in the durability of the equipment. In addition, if the gap is too large, the impact force applied to the refractory block 1 may be too small.

[0023] (narrow pressure process) In parallel with the rigid-body striking process, the refractory block 1 is squeezed between the inner surface of the drum 10 and the hammer 8. As shown in FIG. 2(c), the squeezing section 5 narrows toward the discharge port of the drum, allowing for stronger squeezing. This squeezing allows the slag adhering to the surface of the refractory block 1 to be peeled off.

[0024] (separation process) In this embodiment, the cylindrical surface of the drum is provided with sieve holes having a rectangular or square shape with a side length or a circle equivalent diameter in the range of 15 to 25 mm. The surface layer slag 2 peeled off in any one of the above-mentioned soft whip hitting process, the above-mentioned rigid body hitting process, and the above-mentioned narrow pressure process, or a combination of these, is separated and removed as undersize 6. The refractory raw material 1A with a size of 15 to 25 mm or more remains on the sieve and is collected from the discharge port of the drum 10. Note that a part of the refractory is crushed to a size of 15 to 25 mm or less and discharged together with the slag.

[0025] In this embodiment, there is no need to crush the used refractory block 1 in advance or scrape its surface. Therefore, the work involved in the previous pre-treatment can be omitted. In addition, the regenerated refractory raw material 1A and the peeled slag 2 can be easily sieved. In addition, there is also an effect that high purity refractory raw material can be secured at a high yield. For example, regenerated refractory raw material with a purity of 95% by mass or more can be recovered at a yield of 70% by mass or more. EXAMPLES

[0026] The present invention will be described in more detail with reference to examples, but the present invention is not limited to the following examples.

[0027] Example 1 1 and 2, a comparison was made on the ability to peel off the slag 2 adhering to the surface of the refractory block 1 by changing the rotation speed of the drum 10, the rotation speed of the rotating tool 9, and the number of chains 7 and hammers 8. A refractory block 1 with slag (slag content: about 16% by mass) was prepared, and this was placed in a rotating drum device 101 in which the chains 7 and hammers 8 were attached to the rotating shaft 9A of the rotating tool 9.

[0028] In this refractory raw material manufacturing apparatus 100, first, the area from the charging port of the drum 10 to 50% of the axial length of the rotating shaft was set as the chain installation range 3, and the remaining 50% was set as the hammer installation range 4. The rotation speed of the drum 10 per unit time was changed to 0-70 Hz, and the rotation speed of the rotating tool 9 per unit time was fixed to 60 Hz, and an experiment was conducted to recover the refractory raw material 1A from the refractory block 1. The results are shown in FIG. 4(a). The rotation speed of the drum 10 per unit time was fixed to 10 Hz, and the rotation speed of the rotating tool 9 per unit time was changed to 10-120 Hz, and an experiment was conducted to recover the refractory raw material 1A from the refractory block 1. The results are shown in FIG. 4(b). The refractory purity is expressed as the mass % of the refractory excluding the surface layer slag 2 in the recovered refractory raw material 1A. The recovery yield of the refractory is expressed as the mass % of the recovered refractory raw material 1A relative to the charged refractory block 1.

[0029] From FIG. 4(a), it can be seen that when the rotation speed of the drum 10 per unit time is in the range of 10 to 60 Hz, the recovery yield of the refractory is good, at 70 mass% or more. The lower the rotation speed of the drum 10 per unit time, the higher the refractory purity tends to be. This is thought to be because the lower the rotation speed of the drum, the lower the conveying speed of the refractory block in the drum, and the relatively higher the number of strikes of the rotating tool. When the rotation speed of the drum 10 per unit time is 40 Hz or less, a refractory purity of 90 mass% or more can be obtained, and when it is 20 Hz or less, a refractory purity of 95 mass% or more can be obtained. On the other hand, when the drum rotation speed is reduced too much, the refractory block 1 is not conveyed, and the yield is significantly reduced.

[0030] As shown in FIG. 4(b), when the rotation speed per unit time of the rotating tool 9 is in the range of 30 to 80 Hz, the refractory purity is good, at 95 mass% or more. When the rotation speed per unit time of the rotating tool 9 is in the range of 40 to 70 Hz, the refractory purity is particularly excellent, at 97 mass%. On the other hand, the higher the rotation speed per unit time of the rotating tool 9 is, the lower the recovery yield of the refractory is. When the rotation speed per unit time of the rotating tool 9 is 70 Hz or less, a recovery yield of the refractory of 70 mass% is obtained.

[0031] Example 2 Using the same equipment as in Example 1, the rotation speed per unit time of the drum 10 was set to 10 Hz, and the rotation speed per unit time of the rotating tool 9 was set to 10 Hz. The attachment range of the chain 7 and the hammer 8 was changed to carry out an experiment to recover the raw refractory material 1A from the refractory block 1, and the results are shown in Fig. 5. The attachment range 3 of the chain is expressed as a percentage of the axial length of the rotating shaft 9A of the rotating tool 9 from the entrance of the refractory block 1 into the drum 10, and the hammer 8 is attached in the remaining axial length direction of the rotating shaft to the discharge outlet of the drum 10.

[0032] From the results in Figure 5, the larger the chain installation range 3, the higher the refractory recovery yield and, conversely, the lower the refractory purity. To achieve a refractory recovery yield of 70 mass% or more, the chain installation range 3 needs to be 40% or more. On the other hand, to achieve a refractory purity of 95 mass% or more, the chain installation range 3 needs to be 70% or less, to achieve a refractory purity of 97 mass% or more, the chain installation range 3 needs to be 60% or less, and to achieve a refractory purity of 97.5 mass% or more, the chain installation range 3 needs to be 50% or less. [Industrial Applicability]

[0033] The technology disclosed in the present invention can recover high-purity regenerated refractory raw material from used refractories with a high yield, which contributes to the effective utilization of resources and is industrially useful. [Explanation of symbols]

[0034] 1 (Used) Refractory Block 1A (Recovered) Refractory Raw Materials 2. Surface-adhering slag (surface deposits) 3 Chain installation range 4 Hammer (striker) installation range 5. Clamping section 6 Under the sieve 7 Chain 8 Hammer (striker) 9 Rotary tools 9A Rotating shaft (of a rotating tool) 10 (Rotating) Drum (Cylindrical Body) 100 Refractory material manufacturing equipment 101 Rotating drum device (high speed agitator mixer)

Claims

1. An apparatus for producing a refractory raw material by separating and removing surface deposits from a refractory block having an adhesion layer on its surface, comprising: a cylindrical body having a sieve hole and rotating about a symmetrical axis; a rotating tool having a rotation axis positioned differently from the rotation axis of the cylindrical body and rotating independently of the cylindrical body; A high-speed agitating mixer having The rotary tool has a cable or chain fixed to the rotary shaft and a striker fixed to the rotary shaft, The refractory block is charged into the charging port of the cylinder, and surface deposits are separated and removed as undersize material, and the remainder is recovered from the discharge port of the cylinder as refractory raw material.

2. 2. The apparatus for manufacturing a refractory raw material according to claim 1, wherein the rotating tool has a cable or a chain extending from an inlet side of the refractory block to a range of 40 to 70% of an axial length of the cylinder, and has a striker extending from an outlet side of the refractory raw material to a range of the remaining axial length of the cylinder, and the cable or the chain and the striker are provided at one or more locations in a circumferential direction of the rotating shaft.

3. 2. The apparatus for producing a refractory raw material according to claim 1, wherein the sieve holes provided in the cylindrical body have a rectangular or square shape with a side length or a circle equivalent diameter in the range of 15 to 25 mm.

4. The rotation axis of the rotating tool is configured to be closer to the rotation axis of the cylinder body at the inlet side of the cylinder body and farther from the rotation axis of the cylinder body at the outlet side of the cylinder body, The ends of the rope and the chain are configured to have a gap in the range of more than 0 mm and not more than 150 mm when closest to the inner surface of the cylindrical body, 2. The apparatus for producing a refractory raw material according to claim 1, wherein the tip of the striker is configured to have a gap in the range of more than 0 mm and not more than 50 mm when the tip of the striker is closest to the inner surface of the cylindrical body.

5. Using the apparatus for producing a refractory raw material according to any one of claims 1 to 4, A method for producing a refractory raw material by separating and removing a surface deposit from a refractory block having an adhesion layer on its surface, comprising the steps of: The method for producing a refractory raw material comprises setting the rotation speed of the cylindrical body to 10 to 60 Hz and setting the rotation speed of the rotating tool to 30 to 80 Hz or less.

6. An apparatus for separating and removing surface deposits from a refractory block having an adhesion layer on its surface, comprising: a cylindrical body having a sieve hole and rotating about a symmetrical axis; a rotating tool having a rotation axis positioned differently from the rotation axis of the cylindrical body and rotating independently of the cylindrical body; A high-speed agitating mixer having The rotary tool has a cable or chain fixed to the rotary shaft and a striker fixed to the rotary shaft, The refractory block is charged into the charging port of the cylinder, and surface deposits are separated and removed as undersize, while the remainder is recovered from the discharge port of the cylinder as refractory raw material.

7. 7. The surface deposit separation device according to claim 6, wherein the rotating tool has a cable or a chain extending from an inlet side of the refractory block to a range of 40 to 70% of an axial length of the cylinder, and has a striker extending from an outlet side of the refractory raw material to a range of the remaining axial length of the cylinder, and the cable or the chain and the striker are provided at one or more locations in a circumferential direction of the rotating shaft.

8. 7. The surface deposit separating device according to claim 6, wherein the sieve holes provided in the cylindrical body have a rectangular or square shape with a side length or a circle equivalent diameter in the range of 15 to 25 mm.

9. The rotation axis of the rotating tool is configured to be closer to the rotation axis of the cylinder body at the inlet side of the cylinder body and farther from the rotation axis of the cylinder body at the outlet side of the cylinder body, The ends of the rope and the chain are configured to have a gap in the range of more than 0 mm and not more than 150 mm when closest to the inner surface of the cylindrical body, 7. The surface deposit separating device according to claim 6, wherein the tip of the striker is configured to have a gap in the range of more than 0 mm and not more than 50 mm when closest to the inner surface of the cylindrical body.

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