Coke oven repair method

Abstract

To provide a method for repairing a coke oven, which enables early repair of the coke oven.SOLUTION: There is provided a method for repairing a coke oven having a combustion chamber with a gas vent. The method for repairing a coke oven includes: an introducing step of introducing a refractory material through an inlet provided at a top of the combustion chamber; a dismantling step of dismantling a wall of the combustion chamber; a recovery and cleaning step of recovering the refractory material and cleaning the gas vent; and a repairing step of repairing the combustion chamber.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The present invention relates to a method for repairing a coke oven having a combustion chamber with a gas vent. [Background technology]

[0002] A coke oven consists of an upper structure in which carbonization chambers and combustion chambers are arranged alternately across the oven width, and a lower structure in which heat regenerators are arranged to supply combustion air and fuel gas to the combustion chambers. The coal charged into the carbonization chamber receives the heat generated in the combustion chamber through the bricks in the wall of the coke oven and is carbonized into coke.

[0003] Once the coke is produced, the furnace cover installed on one side of the carbonization chamber is opened, and the coke is pushed out to the open side using an extruder installed on the other side of the carbonization chamber, and the coke is discharged.

[0004] Coke ovens are repeatedly subjected to carbonization and discharge for periods exceeding 20 to 30 years. The bricks on the walls of the coke oven's carbonization chamber and combustion chamber are worn out by such long-term use.

[0005] Furthermore, each time coke is discharged, the cover on one side of the coke chamber is opened, exposing the chamber to drastic temperature changes. As a result, the bricks on the wall on the side where the cover is installed are subject to particularly severe wear. As described above, the walls of coke ovens are subject to wear due to long-term use and temperature changes, and are therefore repaired by replacing bricks.

[0006] Patent Document 1 discloses a technique for repairing such coke ovens, in which the bricks in the combustion chamber are dismantled and then repaired using a refractory assembly formed outside the oven. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Patent No. 3397723 Summary of the Invention [Problem to be solved by the invention]

[0008] The number of combustion chambers requiring repairs such as those described above is increasing year by year, and there is a demand for shortening the repair work period. When repairing the wall of a combustion chamber, it is necessary to plug the gas holes provided in the combustion chamber.

[0009] Conventionally, contractors would break down the furnace wall from the coking chamber to enter the combustion chamber and then place insulation and an iron plate over the gas hole to plug it. However, this conventional method requires time to break down the furnace wall. In addition, fragments of the broken furnace wall get into the gas hole, which requires time to clean the gas hole.

[0010] The present invention has been made in view of the above circumstances, and has as its object to provide a method for repairing a coke oven that enables early repair of the coke oven. [Means for solving the problem]

[0011] In order to solve the above problems, the present invention has the following features. [1] A method for repairing a coke oven having a combustion chamber provided with a gas hole, comprising: a charging step of charging refractory material through a charging port provided at the top of the combustion chamber; a dismantling step of dismantling a wall portion of the combustion chamber; a recovery and cleaning step of recovering the refractory material and cleaning the gas hole; and a repairing step of repairing the combustion chamber. [2] [1] The method for repairing a coke oven according to [1], wherein in the charging step, the refractory material is charged until the gas hole is blocked. [3] The refractory material is fixed in a compressed state from a blanket state by a fixing portion, The method for repairing a coke oven according to [1] or [2], wherein in the charging step, the refractory material is charged when the temperature of the combustion chamber is higher than the heat-resistant temperature of the fixing portion. [4] The heat-resistant temperature of the fixing portion of the refractory material is 300°C or less, The method for repairing a coke oven according to [3], wherein in the charging step, the refractory material is charged when the temperature of the combustion chamber is 300 to 900°C. [5] The method for repairing a coke oven according to [3] or [4], wherein the refractory material is compressed into a roll shape or a bellows shape. [Effects of the Invention]

[0012] According to the coke oven repair method of the present invention, since it includes a step of introducing refractory material through an inlet provided at the top of the combustion chamber, the gas hole can be plugged with refractory material before the contractor enters the combustion chamber. This significantly shortens the time required for plugging the gas hole. Furthermore, since the gas hole can be plugged before the combustion chamber wall is destroyed, it is possible to prevent foreign matter such as wall fragments from entering the gas hole. This reduces the time required to clean the gas hole. As a result, it is possible to repair the coke oven at an early stage. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 1 is an explanatory diagram showing an overview of a coke oven. [Figure 2] FIG. 2 is a cross-sectional view of the combustion chamber of FIG. 1. [Figure 3] FIG. 2 is an explanatory diagram showing an outline of an injection port formed in a combustion chamber. [Figure 4] FIG. 2 is an explanatory diagram showing an outline of a gas hole formed in a combustion chamber. [Figure 5] 1 is a process flow of a method for repairing a coke oven. [Figure 6] FIG. 6 is an explanatory diagram showing an outline of the refractory material charged in the charging step of step S02 in FIG. 5. [Figure 7] FIG. 6 is an explanatory diagram showing an aspect of the loading step in step S02 of FIG. 5. [Figure 8] 1 shows an outline of a charging process using a refractory material according to Modification 1. [Figure 9] 10 shows an outline of a charging process using a refractory material according to Modification 2. [Figure 10] 10 shows an outline of a charging process using a refractory material 40 according to a third modification. DETAILED DESCRIPTION OF THE INVENTION

[0014] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Fig. 1 shows an outline of a coke oven. As shown in Fig. 1, a coke oven 100 has a combustion chamber 10 and a carbonization chamber 20 provided adjacent to each other.

[0015] In FIG. 1, the combustion chamber 10 and the coking chamber 20 are formed in a rectangular parallelepiped shape. The combustion chamber 10 has an input port 11 at its top. The input port 11 is, for example, an inspection hole also called a flue hole. A plurality of input ports 11 are formed along the longitudinal direction of the combustion chamber 10. The input ports 11 are closed by lids (not shown).

[0016] The combustion chamber 10 is provided with a gas hole 12 and a gas hole 13 that is lower in height than the gas hole 12. Two gas holes 12 and two gas holes 13 are provided in parallel with each other. The gas holes 12 and 13 are connected to a heat regenerator (not shown) and eject air and fuel gas. The gas holes 12 and 13 are through-holes formed in a refractory material such as brick, for example.

[0017] Fig. 2 is a cross-sectional view of the combustion chamber 10. As shown in Fig. 2, the combustion chamber 10 is provided with a partition wall 14 extending in the height direction. A plurality of partition walls 14 are formed along the longitudinal direction of the combustion chamber 10.

[0018] Gas holes 12 and 13 are provided in storage space 15, which is separated by partition wall 14. Gas holes 12 and 13 eject air and fuel gas toward storage space 15. In addition, feed port 11 is provided so as to face storage space 15. Gas holes 12 and 13 are provided, for example, at positions where an installer can see them from feed port 11.

[0019] 3 shows an overview of the charging port 11. The charging port 11 is formed, for example, in a cylindrical shape. Although there are no particular limitations on the charging port 11, in this embodiment, the charging port 11 is formed in a cylindrical shape with a diameter D1. Note that the charging port 11 is not limited to an inspection hole, and may be any hole formed so that a refractory material, which will be described later, can be inserted into the combustion chamber 10.

[0020] Fig. 4 shows an overview of gas hole 12 and gas hole 13. As shown in Fig. 4, they are formed in a rectangular shape when viewed from above. In the example shown in Fig. 4, gas hole 12 and gas hole 13 are provided with a length L1 in the longitudinal direction and a length L2 in the lateral direction.

[0021] Of the longitudinal length L1 and the lateral length L2 of the gas holes 12 and 13, it is preferable that at least the lateral length L2 is formed shorter than the diameter D1 of the charging port 11. By forming the gas holes 12 and 13 in this manner, it is possible to prevent a refractory material, which will be described later, from entering the gas holes 12 and 13.

[0022] The gas holes 12 and 13 are provided with a distance L3 therebetween. In the example shown in Fig. 4, the two gas holes 12 are provided with a distance L4 therebetween. The two gas holes 13 are provided with a distance L4 therebetween.

[0023] Fig. 5 shows a process flow of the coke oven repair method. As shown in Fig. 5, in the coke oven repair method, an opening step is performed by an operator removing the lid portion that closes the inlet 11 of the combustion chamber 10 (step S01).

[0024] Next, a loading step is carried out by an operator loading refractory material through the loading port 11 of the combustion chamber 10 (step S02). When the loading step of step S02 is completed, an operator places a lid on the loading port 11 of the combustion chamber 10, carrying out a closing step (step S03). The closing step of step S03 can be carried out at any timing after the loading step is carried out.

[0025] Thereafter, a dismantling process is carried out by a builder dismantling the wall of the combustion chamber 10 (step S04), and a recovery and cleaning process is carried out by recovering the refractory material of the combustion chamber 10 and cleaning the gas holes 12 and 13 (step S05). Finally, a repair process is carried out by the builder repairing the combustion chamber 10 by stacking bricks (step S06).

[0026] Fig. 6 shows an overview of the refractory material 30 charged in the charging process of step S02 in Fig. 5. As shown in Fig. 6, the refractory material 30 can be, for example, a blanket-like insulating material with a heat-resistant temperature of 1000°C or higher. Although not particularly limited, alkaline earth silicate (AES) wool can be used as such a refractory material.

[0027] As shown on the left side of Fig. 6, the refractory material 30 may have a blanket-like base 31 and a fixing portion 32 that fixes the base 31 in a compressed state. In the example shown in Fig. 6, the base 31 is folded in an accordion-like shape. The fixing portion 32 fixes the base 31 in a folded state, in other words, in a state where the base 31 is compressed from a blanket-like shape.

[0028] In this embodiment, the refractory material 30 is formed into a columnar shape by fixing the compressed state of the base 31 with the fixing portion 32. The refractory material 30 is not particularly limited, but may have, for example, an axial length of 200 to 400 mm and a thickness, which is the length in the folding direction of the base 31, of 50 to 70 mm. The folding length in the direction perpendicular to the axial direction and the thickness direction is preferably 60 to 80 mm. The refractory material 30 is preferably folded four or more times.

[0029] The fixing portions 32 may be provided at a plurality of locations in the axial direction. The distance between adjacent fixing portions 32 may be, for example, 30 mm or more. By providing the fixing portions 32 in this manner, it is possible to prevent, for example, one end from being compressed and the other end from being expanded. This allows the refractory material 30 to be smoothly charged through the charging port 11.

[0030] The fixing part 32 is not particularly limited, but its heat resistance temperature is preferably higher than room temperature and lower than 900° C., more preferably 50 to 300° C., and more preferably 70 to 250° C. The heat resistance can be measured according to the standard defined in JIS S 2029 2002, for example.

[0031] For example, a metal wire such as aluminum or a tin-based alloy used for brazing can be used as the fixing part 32. Alternatively, a band or string made of rubber or resin can be used as the fixing part 32. There are no particular limitations on the resin, but examples of resin that can be used include nylon, polypropylene, polystyrene, polyethylene, polyethylene terephthalate, and fluorocarbon.

[0032] By configuring the refractory material 30 in this manner, the size required for charging through the charging port 11 can be reduced. Furthermore, as shown on the right side of Fig. 6, after being charged through the charging port 11, when the heat resistance temperature of the fixing portion 32 is reached, the fixing portion 32 becomes weaker and the base portion 31 is deployed. This allows the amount of refractory material 30 to be charged to be reduced. In other words, by the refractory material 30 being deployed in the combustion chamber 10, the gas holes 12 and 13 can be efficiently blocked.

[0033] In addition, by folding the base 31 in an accordion-like shape, a reaction force can be applied in the folding direction of the base 31. Therefore, the base 31 can be easily unfolded.

[0034] In particular, when the base 31 of the refractory material 30 is formed from a blanket-like insulating material, the compression ratio can be increased. Therefore, it is easy to compress the refractory material 30 to a size that can pass through the inlet 11.

[0035] The refractory material 30 is preferably formed so that the length L5 when deployed is longer than the distance L3 between the gas hole 12 and the gas hole 13. For example, when the distance L3 is 130 mm, the length L5 of the refractory material 30 when deployed is preferably set to 150 to 220 mm.

[0036] By forming the refractory material 30 in this manner, it is possible to increase the possibility that one refractory material 30 will cover two or more of the gas holes 12 and 13. This increases the efficiency of plugging by the refractory material 30.

[0037] From this point of view, when the diameter D1 of the insertion port 11 is 100 mm, the thickness of the base 31 is preferably 25 mm or less, and more preferably 13 mm or less.

[0038] Fig. 7 shows a state in which the refractory material 30 is charged in the charging step of step S02 in Fig. 5. As shown in Fig. 7, in the charging step of step S02, for example, the refractory material 30 is charged with the axis of the charging port 11 and the axis of the refractory material 30 aligned. The refractory material 30 is charged until the gas holes 12 and 13 are visually blocked by the refractory material 30 by an installer.

[0039] In this case, minute gaps that cannot be visually confirmed by an installer may be provided in gas holes 12 and 13. For example, 95% or more of the opening area of ​​gas holes 12 and 13 may be shielded, preferably 98% or more, and more preferably 99% or more.

[0040] In the charging step of step S02, the refractory material 30 is preferably charged when the temperature of the combustion chamber 10 is 300 to 900°C. It is more preferable that the refractory material 30 is charged when the temperature of the combustion chamber 10 is equal to or higher than the melting point of the fixing part 32. The temperature of the combustion chamber 10 can be measured using a radiation thermometer from the charging port 11.

[0041] By performing the loading step in step S02 when the temperature of the combustion chamber 10 is 300°C or higher, the fixing part 32 can be easily softened and the base part 31 can be expanded from a compressed state. In addition, by performing the loading step in step S02 when the temperature of the combustion chamber 10 is 900°C or lower, the heat countermeasures required by the installer at the top of the coke oven can be made minor.

[0042] According to the coke oven repair method of the present invention, since it includes a step of introducing refractory material 30 through an inlet 11 provided at the top of the combustion chamber, the gas holes 12, 13 can be plugged with the refractory material 30 before the contractor enters the combustion chamber 10. This significantly shortens the plugging work of the gas holes 12, 13. Furthermore, since the gas holes 12, 13 can be plugged before the wall of the combustion chamber 10 is destroyed, it is possible to prevent foreign matter such as wall fragments from entering the gas holes 12, 13. This reduces the time required to clean the gas holes 12, 13. As a result, it is possible to repair the coke oven 100 at an early stage.

[0043] (Variation 1) In the above-described embodiment, the refractory material 30 has been described as having a blanket-like base 31 compressed into a bellows shape. However, the compression of the refractory material is not limited to this, and it may be formed into, for example, a roll shape.

[0044] FIG. 8 shows an overview of the charging process using the refractory material 40 according to the first modification. As shown in FIG. 8, the refractory material 40 has, for example, a blanket-shaped base 41 and a fixing portion 42 that fixes the base 41 in a compressed state. In the example shown in FIG. 8, the base 41 is wound in a roll shape. The base 41 can be made of the same material as the base 31 in the above-described embodiment. The fixing portion 42 can be made of the same material as the fixing portion 32 in the above-described embodiment.

[0045] Furthermore, by winding the base 41 in a roll shape, a reaction force can be applied outward in the winding direction of the base 41. This makes it possible to easily unfold the base 41.

[0046] (Variation 2) Furthermore, the refractory material is not limited to one having such a blanket-like base, and for example, a block-like one may be used. Fig. 9 shows an outline of a refractory material 50 according to the second modification.

[0047] As shown in Fig. 9, the refractory material 50 may be formed, for example, in a block shape. In the example shown in Fig. 9, the refractory material 50 is formed in a spherical shape. In addition to the spherical shape, the refractory material 50 may be formed in, for example, an elongated spheroid, a block, a pyramid, a plate, a prism, or the like.

[0048] The refractory material 50 is not particularly limited, but for example, when it is formed into a spherical shape, ceramic balls or the like can be used. In this case, the diameter of the ceramic balls is formed to be shorter than the diameter D1 of the charging port 11. In addition, it is preferable that the diameter of the ceramic balls is formed to be longer than at least one of the longitudinal length L1 and the lateral length L2 of the gas holes 12 and 13.

[0049] By forming the refractory material 50 in this manner, the refractory material 50 can be introduced into the combustion chamber 10 and can be prevented from entering the gas holes 12 and 13.

[0050] The refractory may be, for example, both the blanket-like refractory 30 having a compressed base and the block refractory 50 charged from the charging port 11. Fig. 10 shows an embodiment in which the refractory 30 and the refractory 50 are charged from the charging port 11 to block the gas holes 12 and 13.

[0051] In this way, by charging both the refractory material 30 and the refractory material 50 from the charging port 11, the refractory material 50 enters into the gaps formed between the blanket-like refractory materials 30. In addition, by pressing the refractory material 30 by the refractory material 50, the gaps formed between the blanket-like refractory materials 30 can be made smaller. Therefore, it is possible to more efficiently block the gas holes 12 and 13.

[0052] Even when the refractory material 40 is configured in this manner, similarly to the above-described embodiment, the plugging operation of the gas holes 12 and 13 can be significantly shortened, and foreign matter such as wall fragments can be prevented from entering the gas holes 12 and 13. As a result, the coke oven 100 can be repaired at an early stage. [Example]

[0053] The time required for repair work was compared between conventional coke oven repair, in which workers enter the combustion chamber and plug the gas holes with plugging material, and coke oven repair, in which refractory material is inserted through the opening to plug the gas holes. The results are shown in Table 1.

[0054] In Table 1, Nos. 1 to 9 are listed as examples of repairs to coke ovens in which refractory material is introduced through the opening to block the gas holes. Nos. 1 to 9 differ in the temperature of the combustion chamber when the refractory material is introduced, the material of the refractory, the shape of the refractory, and the type of fixing part of the refractory. Also, in Table 1, No. 10 is a conventional repair of a coke oven.

[0055] [Table 1]

[0056] As shown in Table 1, in Examples No. 1 to 9, the time required for the introduction process, i.e., the time required for the gas hole to be blocked, was 3 hours. In contrast, in the conventional Example No. 10, it took 24 hours for the gas hole to be blocked. Thus, it was found that in Examples No. 1 to 9, the time required for the gas hole to be blocked can be significantly reduced compared to the comparative example.

[0057] In addition, in the recovery and cleaning process, Nos. 1 to 9 took 48 to 84 hours. In contrast, No. 10, a conventional repair method, took 96 hours. Nos. 1 to 9 were able to reduce the time by more than 12 hours compared to No. 10.

[0058] Furthermore, it was found that the recovery and cleaning process took longer when the temperature of the combustion chamber dropped to room temperature, as in No. 1. Furthermore, as in Nos. 1 to 3, no significant difference was observed between spherical and brick-shaped refractory materials.

[0059] Furthermore, it was found that when the refractory material is constructed using a blanket-shaped base like Nos. 4 to 9, the time required for the recovery and cleaning process is shorter than when using spherical or brick-shaped refractories like Nos. 1 to 3.

[0060] In particular, it was found that when the blanket-like base was folded accordion-like and compressed as in Nos. 7 to 9, the time for the recovery and cleaning process was shorter than when it was compressed into a cylindrical shape as in Nos. 4 to 6. Furthermore, no significant difference was observed when the temperature of the combustion chamber was at or above the heat-resistant temperature of the fixed part. [Explanation of symbols]

[0061] 100 coke ovens 10 Combustion chamber 11 Inlet 12 Gas vent 13 Gas vent 20 Carbonization chamber 30 Refractories 31 Base 32 Fixed part 40 Refractories 41 Base 42 fixed part 50 Refractory

Claims

1. A method for repairing a coke oven having a combustion chamber provided with a gas hole, comprising: a charging step of charging refractory material through a charging port provided at the top of the combustion chamber; a dismantling step of dismantling a wall portion of the combustion chamber; a recovery and cleaning step of recovering the refractory material and cleaning the gas hole; and a repairing step of repairing the combustion chamber.

2. 2. The method for repairing a coke oven according to claim 1, wherein in the charging step, the refractory material is charged until the gas hole is blocked.

3. The refractory material is fixed in a compressed state from a blanket state by a fixing portion, 2. The method for repairing a coke oven according to claim 1, wherein in the charging step, the refractory is charged when the temperature of the combustion chamber is higher than the heat-resistant temperature of the fixing portion.

4. The refractory material is fixed in a compressed state from a blanket state by a fixing portion, 3. The method for repairing a coke oven according to claim 2, wherein in the charging step, the refractory is charged when the temperature of the combustion chamber is higher than the heat-resistant temperature of the fixing portion.

5. The heat-resistant temperature of the fixing portion of the refractory material is 300°C or less, 4. The method for repairing a coke oven according to claim 3, wherein in the charging step, the refractory material is charged when the temperature of the combustion chamber is 300 to 900°C.

6. The heat-resistant temperature of the fixing portion of the refractory material is 300°C or less, 5. The method for repairing a coke oven according to claim 4, wherein in the charging step, the refractory material is charged when the temperature of the combustion chamber is 300 to 900°C.

7. The method for repairing a coke oven according to any one of claims 3 to 6, wherein the refractory material is compressed into a roll shape or a bellows shape.

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