Coke oven repairing method

Abstract

Provided is a coke oven repairing method for repairing bricks of one combustion chamber or bricks of a plurality of continuous combustion chambers forming a coke oven by relaying two or more furnace wall bricks and binder bricks at high temperatures along the furnace length direction from a furnace opening, the coke oven repairing method comprising: a confirmation step for observing, from the furnace opening using a three-dimensional measuring instrument, irregularities of furnace walls of an adjacent non-relaying combustion chamber located adjacent to one side surface of one relaying combustion chamber or a plurality of continuous relaying combustion chambers and irregularities of furnace walls of an adjacent non-relaying combustion chamber located adjacent to a side surface opposite to the one side surface, and thus confirming whether or not the protrusion amount is less than a predetermined value for each of the furnace walls of the adjacent non-relaying combustion chambers; and a relaying step for dismantling, if the protrusion amount of any of the furnace walls of the non-relaying combustion chambers is confirmed to be less than the predetermined value in the confirmation step, a repair-needed site of the furnace walls of the one relaying combustion chamber or the plurality of continuous relaying combustion chambers, and newly laying furnace wall bricks and binder bricks in the dismantled range.

Description

Coke oven repair methods

[0001] The present invention relates to a method for repairing a coke oven in a hot state by replacing oven wall bricks that constitute an oven wall separating a coke oven chamber from a combustion chamber.

[0002] Generally, as shown in Figure 7, a chamber-hearth coke oven has a certain number of coking chambers 51 and combustion chambers 52 arranged alternately above a regenerator chamber 53 to form a furnace battery. A plurality of coal loading ports 54 are opened in the ceiling of each coking chamber 51. These coal loading ports 54 are used to load coal carried by a coal loading car 55 traveling above the coke oven. The coal loaded into the coking chamber 51 through the coal loading port 54 is carbonized by heat from the combustion chamber 52, becoming red-hot coke, which is then pushed out of the coking chamber 51 by an extruder 56. The red-hot coke pushed out of the coking chamber 51 by the extruder 56 is then transferred to a fire extinguisher car 58 via a guide car 57, and transported by the fire extinguisher car 58 to a red-hot coke quenching facility (not shown).

[0003] The coking chamber 51, combustion chamber 52, and regenerator 53 are constructed of a large number of bricks, and inside the combustion chamber 52, as shown in Figure 8, a plurality of flues (vertical flame ducts) 59 are formed along a direction (furnace length direction) perpendicular to the arrangement direction of the coking chamber 51 and the combustion chamber 52. The coking chamber 51 also has a kiln opening into which the extrusion ram 56a (see Figure 7) of the extruder 56 is inserted, and a kiln opening from which the red-hot coke is extruded. Backstays 60 (see Figure 8) made of H-shaped steel or the like are erected near these kiln openings to prevent deformation or collapse of the oven walls.

[0004] In such coke ovens, wall-forming bricks that form the walls of the combustion chamber 52 can be significantly worn. Therefore, conventionally, coke ovens are hot-repaired by replacing significantly worn wall-forming bricks with new bricks (see, for example, Patent Document 1). Various methods for repairing by replacing bricks are known (see Patent Documents 2 to 6).

[0005] Japanese Patent No. 5347614 Japanese Patent No. 6183800 Japanese Patent No. 5991478 Japanese Patent No. 6753389 Japanese Patent No. 5365040 Japanese Patent Application Laid-Open No. 2019-108510

[0006] However, when the bricks in the combustion chamber of a coke oven are partially re-laid from the kiln opening by a few flue or when all the bricks are re-laid (through re-laid), the following problem occurs: In these cases, the bricks of the adjacent combustion chamber adjacent to the repaired combustion chamber or the remaining bricks of the unrepaired portion that was not dismantled tend to protrude into the coking chamber after the repair. If the bricks of the combustion chamber protrude into the coking chamber, when the coke that has completed carbonization in the coking chamber is discharged using an extruder, the extrusion ram comes into contact with the protruding bricks and stops, causing a problem of clogging, in which the coke cannot be discharged out of the oven.

[0007] The present invention aims to solve the above problems and provide a method for repairing coke ovens, which, when hot repairing bricks that make up the walls of a coke oven combustion chamber, prevents the remaining bricks in adjacent non-replaced combustion chambers that do not require repair and the remaining bricks in the non-repaired parts that remain without being dismantled from protruding from the oven wall toward the carbonization chamber after repair, thereby preventing clogging.

[0008] The method for repairing a coke oven of the present invention is a method for repairing a coke oven by hot replacing two or more oven wall bricks and binder bricks from the oven mouth along the oven length direction of one combustion chamber or multiple consecutive combustion chambers that constitute the coke oven, and the method includes measuring, from the oven mouth with a three-dimensional measuring device, the recesses of the oven wall of an adjacent non-replacement combustion chamber adjacent to one side of the one replacement combustion chamber or multiple consecutive replacement combustion chambers and the oven wall of an adjacent non-replacement combustion chamber adjacent to the other side of the one replacement combustion chamber or multiple consecutive replacement combustion chambers. This method for repairing a coke oven comprises a confirmation step of observing the protrusions and confirming that the protrusion amounts of the oven walls of the adjacent non-replacement combustion chambers are less than a predetermined value, and a re-laying step of dismantling the areas of the oven walls of one re-laying combustion chamber or multiple consecutive re-laying combustion chambers that require repair and stacking new oven wall bricks and binder bricks in the dismantled area when it is confirmed in the confirmation step that the protrusion amounts of the oven walls of the adjacent non-re-laying combustion chambers are less than the predetermined value.

[0009] In the method for repairing a coke oven according to the present invention configured as described above, (1) the predetermined value of the overhang amount is a value that can ensure a clogging rate calculated by the following formula (1) that does not impede normal operation: Clogging rate (%) = 5 × 10 －８ ×d ５...(1) where d (mm) is the amount of overhang, (2) the value that can ensure a packing rate that does not hinder normal operation is 5%, and by calculating d from the formula (1), the predetermined value of the amount of overhang is 40 mm, (3) including a repair range determination step of determining the range of furnace wall bricks and binder bricks that need repair by observing the unevenness of the furnace wall from the kiln mouth with a three-dimensional measuring device before dismantling the area of ​​the transfer combustion chamber that needs repair, and a step of further confirming the convex parts of the furnace wall determined in the repair range determination step from the flue hole and dismantling binder bricks up to the binder bricks that are closer to the kiln mouth than the binder bricks that are determined to be sound, (4) if the range of furnace wall bricks and binder bricks that need repair includes a coal loading car rail, including a step of reinforcing the rail by providing a gap between the underside of the coal loading car rail support and the ceiling, on which the coal loading car load will not directly act, (5) A process for maintaining the furnace wall temperature of an adjacent non-replacement combustion chamber adjacent to the replacement combustion chamber and the furnace wall temperature of an unrepaired portion of the replacement combustion chamber for which the binder bricks have been confirmed to be sound at 400°C or higher; (6) A first new brick laying process for laying one flue worth of first new furnace wall bricks and binder bricks on surfaces exposed as a result of the brick dismantling of the furnace wall bricks and binder bricks that are the remaining bricks of the unrepaired portion that have been dismantled; an insulating member attaching process for attaching insulating members to the exposed surfaces of the furnace wall bricks and binder bricks that are the first new bricks that have been laid in the first new brick laying process; and a second new brick laying process for laying second new furnace wall bricks and binder bricks in the remaining repair range while removing the insulating members from the lower parts.(7) A process of forming a joint penetrating vertically at the boundary between the furnace wall portion that has been re-repaired and the furnace wall portion that has not been repaired, and re-stacking the furnace wall bricks; a process of arranging, in the carbonization chamber at and near the boundary, a non-repaired-side anti-extension member that bridges between at least the furnace wall bricks of the non-repaired portion and the furnace wall surface facing the furnace wall bricks across the space of the carbonization chamber, and a repaired-side anti-extension member that bridges between at least the furnace wall bricks of the re-repaired furnace wall portion and the furnace wall surface facing the space of the carbonization chamber, and then heating the furnace; and a process of spraying a thermal spray material into the joint that is the gap at the boundary between the bricks of the re-repaired portion and the bricks of the non-repaired portion after the temperature has been raised. (8) A first extension prevention member installation process for installing a first extension prevention member that maintains the width of the second coking chamber constant at a position including at least a position corresponding to the first binder brick from the kiln opening among a plurality of binder bricks that form the first adjacent non-transferring combustion chamber, which is adjacent to the transfer combustion chamber to be repaired in the furnace width direction, and a second adjacent non-transferring combustion chamber further beyond that; a repair process for dismantling and re-installing the furnace wall bricks and binder bricks of the repaired portion of the transfer combustion chamber; a second extension prevention member installation process for installing a second extension prevention member that maintains the width of the first coking chamber constant at a position including at least a position corresponding to the first binder brick from the kiln opening among a plurality of binder bricks that form the transfer combustion chamber, which is transferred; and a heating process for heating the transferred transfer combustion chamber. This is considered to be a more preferable solution.

[0010] According to the coke oven repair method of the present invention, before dismantling the bricks of the transfer combustion chamber to be repaired, the condition of the wall of the adjacent non-transfer combustion chamber can be observed, thereby determining the range of oven wall bricks and binder bricks to be appropriately repaired, and solving the problem of the wall of the adjacent non-transfer combustion chamber protruding into the coke oven chamber after repair.

[0011] FIG. 1 is a diagram for explaining repair when there is no overhang on the furnace wall of an adjacent non-transferring combustion chamber. FIG. 2 is a diagram for explaining repair when there is no overhang on the furnace wall of an adjacent non-transferring combustion chamber. FIG. 3 is a diagram for explaining repair when there is no overhang on the furnace wall of an adjacent non-transferring combustion chamber. FIG. 4 is a diagram for explaining repair when there is an overhang on the furnace wall of an adjacent non-transferring combustion chamber. FIG. 5 is a diagram for explaining repair when there is an overhang on the furnace wall of an adjacent non-transferring combustion chamber. FIG. 6 is a diagram for explaining the implementation state of Example 1. FIG. 7 is a diagram for explaining the implementation state of Example 2. FIG. 8 is a diagram for explaining the implementation state of Example 3. FIG. 9 is a graph showing the relationship between the clogging rate and the overhang amount when the coal loading amount is 30 t, which is full filling. FIG. 10 is a diagram for explaining an example of a known coke oven. FIG. 11 is a diagram of a known coke oven viewed from above.

[0012] The following describes in detail the embodiments of the present invention. Note that the following embodiments are merely examples of methods for realizing the technical idea of ​​the present invention, and are not intended to limit the configuration to the following. In other words, the technical idea of ​​the present invention can be modified in various ways within the technical scope described in the claims.

[0013] <Summary of the Invention> The present invention relates to a method for repairing coke ovens and was achieved based on the following findings. Conventional coke oven repair methods have had a problem in that, when repairing a transfer combustion chamber, the furnace wall of an adjacent non-transfer combustion chamber adjacent to the transfer combustion chamber overhangs toward the coking chamber. Furthermore, if the adjacent non-transfer combustion chamber overhangs significantly, it is difficult to properly install insulation panels, resulting in a drop in the temperature of the adjacent non-transfer combustion chamber and overhanging into the coking chamber. To solve these problems, the condition of the furnace wall of the adjacent non-transfer combustion chamber is observed before repairing the transfer combustion chamber, and the furnace wall of the adjacent non-transfer combustion chamber is determined to be sound if it satisfies certain conditions. It has been discovered that by repairing the transfer combustion chamber when the adjacent non-transfer combustion chamber is determined to be sound, the furnace wall of the adjacent non-transfer combustion chamber does not overhang toward the coking chamber after repair.

[0014] In the present invention, the adjacent non-transferring combustion chamber adjacent to a transfer combustion chamber refers to the adjacent non-transferring combustion chamber adjacent to one side of one transfer combustion chamber or a series of multiple consecutive transfer combustion chambers and the adjacent non-transferring combustion chamber adjacent to the other side. However, in the following explanation, the coke oven repair method of the present invention will be explained assuming that the transfer combustion chamber is one transfer combustion chamber. It goes without saying that the following explanation can be applied to a series of multiple consecutive transfer combustion chambers in the same way.

[0015] 1A to 1C are diagrams illustrating repairs when there is no overhang on the furnace wall of an adjacent non-transfer combustion chamber. First, as shown in FIG. 1A, the unevenness of the furnace wall of the adjacent non-transfer combustion chamber adjacent to one side of the transfer combustion chamber to be repaired and the furnace wall of the adjacent non-transfer combustion chamber adjacent to the other side are observed using a three-dimensional measuring device to confirm that the overhang of the furnace wall of the adjacent non-transfer combustion chamber is less than a predetermined value. Next, as shown in FIG. 1B, insulation panels are installed on the surface of each adjacent non-transfer combustion chamber facing the transfer combustion chamber to be repaired, and the transfer portion of the transfer combustion chamber is dismantled. Then, as shown in FIG. 1C, transfer is performed on the dismantled portion of the transfer combustion chamber, and the transfer combustion chamber to be repaired is repaired. At this time, in the adjacent combustion chambers whose overhang of the furnace wall was confirmed to be less than the predetermined value in FIG. 1A, none of them have any overhang of the furnace wall, as shown in FIG. 1C.

[0016] 2A to 2C are diagrams illustrating repairs when there is an overhang on the furnace wall of an adjacent non-transfer combustion chamber. First, as shown in FIG. 2A, the unevenness of the furnace wall of the adjacent non-transfer combustion chamber adjacent to one side of the transfer combustion chamber to be repaired and the furnace wall of the adjacent non-transfer combustion chamber adjacent to the other side are observed using a three-dimensional measuring device. FIG. 2A shows an example in which the furnace wall of the adjacent non-transfer combustion chamber adjacent to the upper side of the transfer combustion chamber overhangs by a predetermined value or more, and the furnace wall of the adjacent non-transfer combustion chamber adjacent to the lower side of the transfer combustion chamber overhangs by less than a predetermined value. Next, as shown in FIG. 2B, insulation panels are installed on the surfaces of each adjacent non-transfer combustion chamber facing the transfer combustion chamber to be repaired, and the transfer portion of the transfer combustion chamber is dismantled. In this case, the overhanging portion of the furnace wall of the upper adjacent non-transfer combustion chamber that overhangs by more than the predetermined value will interfere with the installation of the insulation panel. Then, as shown in Figure 2C, the reloaded combustion chamber is reloaded onto the dismantled portion, and the reloaded combustion chamber is repaired. At this time, in the upper adjacent non-reloaded combustion chamber, where the furnace wall overhang was confirmed to be equal to or greater than a predetermined value in Figure 2A, the overhang amount becomes larger after reloading than before reloading, as shown in Figure 2C. On the other hand, in the lower adjacent non-reloaded combustion chamber, where the furnace wall overhang was confirmed to be less than the predetermined value in Figure 2A, the overhang amount remains unchanged before and after reloading, as shown in Figure 2C.

[0017] The coke oven repair method of the present invention, achieved based on the above findings, is a method for repairing a coke oven by hot replacing the bricks of one combustion chamber or multiple consecutive combustion chambers that make up the coke oven with two or more oven wall bricks and binder bricks from the kiln mouth along the oven length direction, and is characterized by including: a confirmation step of observing, from the kiln mouth with a three-dimensional measuring device, the unevenness of the oven wall of an adjacent non-replacement combustion chamber adjacent to one side of one replacement combustion chamber or multiple consecutive replacement combustion chambers and the oven wall of an adjacent non-replacement combustion chamber adjacent to the other side, and confirming that the amount of protrusion of each oven wall of the adjacent non-replacement combustion chamber is less than a predetermined value; and a re-laying step of dismantling the portion of the oven wall of one replacement combustion chamber or multiple consecutive replacement combustion chambers that needs repair, and laying new oven wall bricks and binder bricks in the dismantled area, if it is confirmed in the confirmation step that the amount of protrusion of the oven wall of the adjacent non-replacement combustion chamber is less than the predetermined value.

[0018] According to the coke oven repair method of the present invention, when the bricks constituting the furnace wall of the combustion chamber of a coke oven are hot repaired, the furnace wall of the adjacent non-replacement combustion chamber adjacent to one side and the furnace wall of the adjacent non-replacement combustion chamber adjacent to the other side will no longer protrude toward the carbonization chamber after repair.

[0019] In addition, as a preferred embodiment, the coke oven repair method of the present invention includes a repair range determination step in which, before dismantling the area of ​​the transfer combustion chamber that requires repair, the range of oven wall bricks and binder bricks that require repair is determined by observing the unevenness of the oven wall from the oven mouth using a three-dimensional measuring device, and a step in which the convex parts of the oven wall determined in the repair range determination step are further confirmed from the flue hole, and binder bricks that are closer to the oven mouth than the binder bricks that have been determined to be sound are dismantled up to the binder bricks.

[0020] According to a preferred embodiment of the coke oven repair method of the present invention, when hot repairing the bricks that make up the furnace wall of the combustion chamber of a coke oven, the remaining bricks in the unrepaired part of the replaced combustion chamber that is left undismantled will no longer protrude toward the carbonization chamber after repair.

[0021] <Regarding publicly known technologies suitable for use in the coke oven repair method of the present invention> In the coke oven repair method of the present invention described above, a more preferred embodiment is a coke oven repair method using technologies that have already become publicly known in patent publications and published publications, as exemplified below.

[0022] As described in Patent Document 2 (Japanese Patent No. 6183800), the coke oven repair method of the present invention preferably includes a step of reinforcing a coal car rail by providing a gap between the underside of the coal car rail support and the ceiling, so that the coal car load does not directly act on the rail, when the range of oven wall bricks and binder bricks requiring repair includes the coal car rail, thereby reinforcing the rail. According to this embodiment, the coke oven repair method of the present invention can accurately suppress damage to the ceiling on which the coal car rail support is installed (damage and deformation of the ceiling bricks and joints).

[0023] As described in Patent Document 3 (Japanese Patent No. 5,991,478), the coke oven repair method of the present invention preferably includes a step of maintaining the furnace wall temperature of an adjacent non-replacement combustion chamber adjacent to the reloading combustion chamber, and the furnace wall temperature of a non-repaired portion of the reloading combustion chamber where it has been confirmed that the binder bricks are sound, at 400° C. or higher. According to this embodiment, the coke oven repair method of the present invention can provide a partial reloading repair method for a coke oven that improves construction efficiency and has almost or no risk of overhang or falling off.

[0024] As described in Patent Document 4 (Japanese Patent No. 6753389), the coke oven repair method of the present invention preferably includes the following steps: a first new brick laying step of laying one flue of first new bricks, i.e., furnace wall bricks and binder bricks, on surfaces exposed as a result of brick dismantling of the remaining furnace wall bricks and binder bricks in the non-repaired portion after dismantling; an insulating member attaching step of attaching insulating members to the exposed surfaces of the one flue of first new bricks laid in the first new brick laying step; and a second new brick laying step of laying second new bricks, i.e., furnace wall bricks and binder bricks, in the remaining repair area while removing the insulating member from the lower part. According to this embodiment, the coke oven repair method of the present invention can reduce the amount of heat radiation from the surfaces exposed as a result of brick dismantling even in the upper parts of the remaining bricks in the non-repaired portion of the combustion chamber to be repaired, thereby suppressing a temperature drop from the upper to lower parts of the remaining bricks.

[0025] As described in Patent Document 5 (Japanese Patent No. 5,365,040), the coke oven repair method of the present invention preferably includes the steps of: forming vertically penetrating joints at the boundary between the re-repaired oven wall portion and the non-repaired oven wall portion, and re-stacking the oven wall bricks; arranging, at the boundary portion and its vicinity, non-repaired-side extension prevention members so as to bridge between at least the oven wall bricks of the non-repaired portion and the oven wall surface opposing the oven wall bricks and the oven wall bricks across the space of the coke chamber, and repaired-side extension prevention members so as to bridge between at least the oven wall bricks of the re-repaired oven wall portion and the oven wall surface opposing the oven wall bricks and the space of the coke chamber, and then heating the oven; and spraying, after the temperature has been raised, a thermal spray material into the joints, which are gaps at the boundary between the bricks of the re-repaired portion and the bricks of the non-repaired portion. According to this embodiment, in the coke oven repair method of the present invention, it is possible to minimize the protrusion of the boundary between the repaired and non-repaired parts when the temperature of the coke oven oven wall bricks is raised again, and deformation of the oven wall bricks during hot repair can be suppressed.

[0026] In the method for repairing a coke oven of the present invention, as described in Patent Document 6 (JP 2019-108510 A), a first extension prevention member is installed in a second coking chamber between a first adjacent non-transferring combustion chamber adjacent to the transfer combustion chamber to be repaired in the oven width direction and a second adjacent non-transferring combustion chamber further beyond that, at a position including at least a position corresponding to the first binder brick from the oven mouth among a plurality of binder bricks forming the first adjacent non-transferring combustion chamber, to keep the width of the second coking chamber constant at that position. and a heating step of heating the transferred combustion chamber. According to this embodiment, the coke oven repair method of the present invention can appropriately prevent the furnace wall bricks of the transferred combustion chamber and the first adjacent non-transferring combustion chamber from overhanging when repairing the furnace wall bricks and partition bricks near the combustion chamber opening.

[0027] <Preferred embodiment of the predetermined value in the present invention> The preferred predetermined value in the present invention is determined as follows. After carbonization, the coke is discharged from the coke oven into a fire truck by the pusher ram. At this time, jamming may occur due to equipment trouble with the pusher ram. One of the causes of jamming is interference with the movement of the pusher ram due to overhanging combustion chamber bricks.

[0028] In the present invention, a preferred embodiment of a predetermined upper limit of the brick overhang amount at which clogging does not occur is determined based on the relationship between the brick overhang amount and the clogging rate. Specifically, the clogging rate and the overhang amount were actually determined in a coke oven when the coal loading amount was 30 tons, which is the full load. Table 1 below shows the data on the clogging rate and the overhang amount determined when the coal loading amount was 30 tons. Also, Figure 6 is a graph showing the relationship between the clogging rate and the overhang amount based on the data in Table 1.

[0029]

[0030] From the results of Table 1 and FIG. 6, the following formula (1) was obtained by regression analysis: Clogging rate (%) = 5 × 10 －８ ×d ５ ...(1) where d (mm) is the amount of overhang.

[0031] Therefore, it can be seen that the preferred predetermined value in the present invention is a value that can ensure a clogging rate calculated by the formula (1) that does not impede normal operation.

[0032] Here, in normal coke oven operation, if the clogging rate is less than 5%, it is considered that operation can be performed without any problems, and therefore if the overhang amount d satisfies formula (1) < 5%, it is considered that there will be no clogging problems. Therefore, the range of the above d can be calculated from formula (1) as follows: Clogging rate (%) = 5 x 10 －８ ×d ５ <5 ⇔ d < (5 ÷ (5 × 10 －８ )) １／５ = 40 mm (← 10 ８／５ = 39.8) From this result, it can be seen that the preferred predetermined value for the amount of overhang is 40 mm, and an example of a specific range thereof is less than 40 mm.

[0033] Example 1 As shown in Figure 3, for a combustion chamber to be repaired (a replacement combustion chamber) and two combustion chambers adjacent to the combustion chamber to be repaired (adjacent non-replacement combustion chambers) that constitute a coke oven, the unevenness of the furnace wall was measured using a laser scanner at predetermined positions on the kiln mouth bricks of the adjacent combustion chambers (adjacent non-replacement combustion chambers) before and after the replacement of the combustion chamber to be repaired (replacement combustion chamber). In addition, before the replacement of the combustion chamber to be repaired (replacement combustion chamber), the presence or absence of cracks was observed through the flue hole. The results are shown in Table 2 below.

[0034]

[0035] The results in Table 2 show that if the kiln mouth overhang of the adjacent combustion chamber (adjacent non-transferred combustion chamber) before transfer is +40 mm, this will be exacerbated after transfer, so the kiln mouth overhang of the adjacent combustion chamber (adjacent non-transferred combustion chamber) before transfer must be less than +40 mm. Furthermore, if the overhang is ≦15 mm, there will be almost no change after transfer (within the measurement error range). Furthermore, it can be seen that there is a correlation between the size of the kiln mouth overhang and the presence or absence of brick cracks from within the flue hole.

[0036] Example 2 As shown in Figure 4, in an example in which kiln port extension prevention bricks were placed between a combustion chamber (replacement combustion chamber) to be repaired and two combustion chambers (adjacent non-replacement combustion chambers) adjacent to the combustion chamber to be repaired that constitute a coke oven, before and after the combustion chamber to be repaired (replacement combustion chamber) was replaced, the unevenness of the furnace wall was measured using a laser scanner at predetermined positions on the kiln port bricks of the adjacent combustion chambers (adjacent non-replacement combustion chambers). In addition, before the combustion chamber to be repaired (replacement combustion chamber) was replaced, the presence or absence of cracks was observed through the flue hole. The results are shown in Table 3 below.

[0037]

[0038] The results in Table 3 show that installing anti-bulge bricks at the kiln mouth suppresses bulging after reloading. However, when the bulge amount is +40 mm, it is difficult to suppress further bulging even with the anti-bulge bricks.

[0039] Example 3: As shown in Figure 5, a case was investigated in which a portion of a combustion chamber (replacement combustion chamber) was left intact. In this example, kiln-mouth extension prevention bricks were placed between the combustion chamber (replacement combustion chamber) to be partially repaired and two combustion chambers (adjacent non-replacement combustion chambers) adjacent to the combustion chamber (replacement combustion chamber). For this example, before and after the replacement of the combustion chamber (replacement combustion chamber) to be repaired, the unevenness of the furnace wall was measured using a laser scanner at a predetermined position on the kiln-mouth bricks of the adjacent combustion chambers (adjacent non-replacement combustion chambers). Furthermore, before the replacement of the combustion chamber (replacement combustion chamber) to be repaired, the presence or absence of cracks was observed through the flue hole. The results are shown in Table 4 below.

[0040]

[0041] The results in Table 4 show that if there are cracks in the remaining combustion chamber (old bricks), the furnace wall will protrude after replacement (even if that part is not protruding).The results above also show that it is difficult to prevent this, regardless of whether or not protrusion prevention bricks are installed.

[0042] In the coke oven repair method of the present invention, the range of oven wall bricks and binder bricks to be appropriately repaired can be determined by observing the condition of the wall of the adjacent combustion chamber (adjacent non-replacement combustion chamber) before dismantling the bricks of the replacement combustion chamber to be repaired. This solves the problem of the wall of the adjacent combustion chamber (adjacent non-replacement combustion chamber) protruding into the coke oven chamber after repair, which is industrially useful.

[0043] 51 carbonization chamber 52 combustion chamber 53 regenerator 54 coal loading port 55 coal loading car 56 pusher 56a push ram 57 guide car 58 fire extinguishing car 59 flue (vertical flame passage) 60 backstay

Claims

1. A method of repairing a coke oven, in which the bricks of one combustion chamber or the bricks of multiple consecutive combustion chambers that constitute a coke oven are hot repaired by replacing two or more oven wall bricks and binder bricks from the oven mouth along the oven length direction, comprising: a confirmation step of observing the unevenness of the oven wall of an adjacent non-transferring combustion chamber adjacent to one side of said one transfer combustion chamber or multiple consecutive transfer combustion chambers and the oven wall of an adjacent non-transferring combustion chamber adjacent to the other side of said one transfer combustion chamber or multiple consecutive transfer combustion chambers with a three-dimensional measuring device from the oven mouth, and confirming that the protrusion amount of each of the oven walls of the adjacent non-transferring combustion chambers is less than a predetermined value; and a re-laying step of dismantling the portion of the oven wall of said one transfer combustion chamber or multiple consecutive transfer combustion chambers that needs repair, and laying new oven wall bricks and binder bricks in the dismantled area, when it is confirmed in the confirmation step that the protrusion amount of the oven wall of the adjacent non-transferring combustion chamber is less than the predetermined value.

2. The method for repairing a coke oven according to claim 1, wherein the predetermined value of the overhang amount is a value that ensures a clogging rate calculated by the following formula (1) that does not impede normal operation: Clogging rate (%) = 5 x 10 －８ ×d ５ ...(1) Here, d (mm) is the amount of protrusion.

3. A method for repairing a coke oven as described in claim 2, characterized in that the value that can ensure a clogging rate that does not hinder normal operation is 5%, and the specified value of the overhang amount is 40 mm by calculating d from formula (1).

4. A method for repairing a coke oven as described in claim 1, comprising: a repair range determination step of determining the range of oven wall bricks and binder bricks requiring repair by observing the unevenness of the oven wall from the oven mouth with a three-dimensional measuring device before dismantling the area of ​​the transferred combustion chamber requiring repair; and a step of further checking the convex parts of the oven wall determined in the repair range determination step from the flue hole, and dismantling binder bricks up to and including the binder bricks that are closer to the oven mouth than the binder bricks determined to be sound.

5. A method for repairing a coke oven as described in any one of claims 1 to 4, characterized in that if the range of oven wall bricks and binder bricks requiring repair includes a coal car rail, a step of reinforcing the rail by providing a gap between the underside of the coal car rail support base and the ceiling, so that the load of the coal car does not directly act on the rail.

6. A method for repairing a coke oven as described in any one of claims 1 to 4, comprising a step of maintaining the oven wall temperature of an adjacent non-replacement combustion chamber adjacent to the transfer combustion chamber, and the oven wall temperature of a non-repaired portion of the transfer combustion chamber in which the binder bricks have been confirmed to be sound, at 400°C or higher.

7. A method for repairing a coke oven according to any one of claims 1 to 4, comprising: a first new brick laying step of laying one flue of first new bricks, i.e., furnace wall bricks and binder bricks, on surfaces exposed as a result of the dismantling of the remaining bricks of the non-repaired portion after dismantling; a heat insulating material attaching step of attaching heat insulating material to the exposed surfaces of the furnace wall bricks and binder bricks, i.e., one flue of first new bricks laid in the first new brick laying step; and a second new brick laying step of laying second new bricks, i.e., furnace wall bricks and binder bricks, in the remaining repair area while removing the heat insulating material from the lower part.

8. A method for repairing a coke oven according to any one of claims 1 to 4, comprising the steps of: forming a joint that penetrates vertically at the boundary between the oven wall portion that has been re-repaired and the oven wall portion that has not been repaired, and re-laying the oven wall bricks; arranging in the coking chamber, at the boundary portion and its vicinity, a non-repair side anti-extension member that spans between at least the oven wall bricks of the non-repaired portion and the oven wall surface facing the oven wall bricks and the space of the coking chamber, and a repair side anti-extension member that spans between at least the oven wall bricks of the oven wall portion that has been re-repaired and the oven wall surface facing the oven wall bricks and the space of the coking chamber, and then heating the oven; and after heating, spraying a thermal spray material into the joint that is the gap at the boundary between the bricks of the re-repaired portion and the bricks of the non-repaired portion.

9. A first extension prevention member installation process for installing a first extension prevention member that maintains the width of the second coking chamber constant at a position including at least a position corresponding to the first binder brick from the kiln mouth among the multiple binder bricks that form the first adjacent non-transferring combustion chamber in the second coking chamber between the first adjacent non-transferring combustion chamber to be repaired and the second adjacent non-transferring combustion chamber further beyond that; a repair process for dismantling and transferring the furnace wall bricks and binder bricks of the repaired portion of the transfer combustion chamber; a second extension prevention member installation process for installing a second extension prevention member that maintains the width of the first coking chamber constant at a position including at least a position corresponding to the first binder brick from the kiln mouth among the multiple binder bricks that form the transfer combustion chamber in the first coking chamber between the transferred transfer combustion chamber and the first adjacent non-transferring combustion chamber; and a heating process for heating the transferred transfer combustion chamber. The method for repairing a coke oven according to any one of claims 1 to 4, comprising:

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