Coke oven repair method and repair device

Abstract

Provided are a repair method and a repair device for a coke oven, with which, when bricks that form a wall of a combustion chamber of a coke oven are to be repaired while hot, an adjacent combustion chamber and remaining bricks in a portion not being repaired that are left without being dismantled will not bulge toward a carbonization chamber after the repair. The present invention is a coke oven repair method including: a confirmation step in which an oven wall of a combustion chamber that is adjacent to a combustion chamber to be restacked is examined, using a three-dimensional measuring instrument through an oven port, for unevenness to confirm whether the amount of bulging of the oven wall of the adjacent combustion chamber is less than a prescribed value; a restacking step in which, if it was confirmed in the confirmation step that the amount of bulging of the oven wall of the adjacent combustion chamber is less than the prescribed value, parts requiring repair of an oven wall of the combustion chamber to be restacked are dismantled, and oven wall bricks and binder bricks are stacked anew in the scope of the dismantling; and a step in which a pre-formed oven wall refractory aggregate and a pre-formed ceiling section refractory aggregate are used as a newly stacked oven wall and a ceiling section in the combustion chamber to be restacked.

Description

Coke oven repair method and repair device

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

[0002] Generally, as shown in FIG. 12 , a chamber-type coke oven has a plurality of carbonization chambers 51 and combustion chambers 52 above a regenerator chamber 53. These carbonization chambers 51 and combustion chambers 52 are alternately formed above the regenerator chamber 53, and a plurality of coal loading ports 54 are opened in the ceiling of each carbonization chamber 51. These coal loading ports 54 are used to load coal carried by a coal loading car 55 traveling above the coke oven into the carbonization chamber 51. The coal loaded into the carbonization 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 carbonization chamber 51 by an extruder 56. The red-hot coke pushed out of the carbonization 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 13, 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 12) of the extruder 56 is inserted, and a kiln opening from which the red-hot coke is extruded. Backstays 60 (see Figure 13) 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 51 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 8).

[0005] Japanese Patent No. 5347614 Japanese Patent Application Laid-Open No. 2022-110682 Japanese Patent No. 6587951 Japanese Patent No. 6280453 Japanese Patent No. 6482484 Japanese Patent No. 6502435 Japanese Patent No. 6502436 Japanese Patent Application Laid-Open No. 2017-137447

[0006] However, when replacing the bricks in the combustion chamber of a coke oven while it is hot, either by partially replacing a few flue bricks from the kiln mouth or by replacing all the bricks (through replacement), the following problem occurred: the remaining bricks of the adjacent combustion chamber or the unrepaired part that was left undismantled would protrude into the coking chamber after repair.

[0007] The present invention aims to solve the above problems and provide a method and apparatus for repairing coke ovens, which, when hot repairing the bricks that make up the walls of the combustion chamber of a coke oven, prevents the remaining bricks of the adjacent combustion chamber or the unrepaired parts that remain undismantled from protruding into the carbonization chamber after repair.

[0008] The coke oven repair method of the present invention is a method for hot repairing a combustion chamber brick of a coke oven by replacing two or more oven wall bricks and binder bricks from the oven mouth along the oven length direction, and is characterized by comprising: a confirmation step of observing, from the oven mouth with a three-dimensional measuring device, the unevenness of the oven wall of a combustion chamber adjacent to the combustion chamber to be replaced, and confirming that the amount of protrusion of the oven wall of the adjacent combustion chamber is less than a predetermined value; a re-stacking step of dismantling the oven wall of the combustion chamber to be replaced that requires repair and stacking 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 combustion chamber is less than the predetermined value; and a step of using a pre-formed oven wall refractory assembly and a pre-formed ceiling refractory assembly as the newly replaced oven wall and ceiling of the combustion chamber to be replaced.

[0009] The method for repairing a coke oven according to the present invention, configured as described above, includes: (1) the predetermined value is 40 mm; (2) a repair range determination step for determining the range of oven wall bricks and binder bricks that need repair by observing the unevenness of the oven wall from the oven mouth with a three-dimensional measuring device before dismantling the portion of the combustion chamber to be replaced that needs repair; and a step for further confirming the convex portions of the oven wall determined in the repair range determination step from the flue holes and dismantling binder bricks up to the binder bricks that are closer to the oven mouth than the binder bricks determined to be sound; (3) with a portion of the combustion chamber oven wall opened in advance, covering the gas holes and air holes of the existing combustion chamber with a curing member, or filling the gas holes and air holes with insulating material from the flue holes at the top of the combustion chamber oven wall, thereby preventing fallen debris from being mixed into the regenerator when dismantling the combustion chamber to be replaced; (4) Repairing brick cavities formed in the ceilings of adjacent combustion chambers for a pair of combustion chambers formed integrally by stacking one-piece or two-piece precast blocks; (5) Installing an insulating panel by placing it on a transport cart and pulling it with a towing wire into a specified carbonization chamber or by pushing it out with a pusher before dismantling the area of ​​the combustion chamber to be replaced that requires repair; (6) Using a heavy demolition cart when dismantling the area of ​​the combustion chamber to be replaced that requires repair; (7) Using a cart that travels across the furnace to transport and carry in the furnace wall refractory assemblies and the ceiling refractory assemblies; (8) When arranging the furnace wall refractory assemblies and the ceiling refractory assemblies horizontally, using a laser beam to position them horizontally and installing spacers to make the mortar joint thickness uniform; (9) When forming a new ceiling to be replaced, the method includes a step of installing the ceiling refractory assembly and pouring casters into the gaps around the ceiling refractory assembly to fill them; (10) The wall forming the combustion chamber is divided into a plurality of blocks, and integrally molded blocks are fabricated in advance using monolithic refractories;It is believed that a more preferable solution is to dismantle the wall body, carry it out of the furnace, and then carry in the one-piece molded block and position it so that its ends abut against two surfaces that are perpendicular to the ends of the existing wall body, thereby constructing the new wall body.

[0010] Furthermore, the coke oven repair device of the present invention is a coke oven repair device used in the above-mentioned coke oven repair method, which comprises: (1) a slide gate provided on the top of the coke oven, which is capable of moving laterally so as to open the opening that occurs when the coke oven top is dismantled during the coke oven dismantling work and close when the coke oven dismantling work is suspended, and which is provided with safety handrails around it; (2) an insulating structure formed by layering and fixing several types of insulating materials into an iron frame to form an integrated structure, which is provided between the combustion chamber to be replaced and the adjacent combustion chamber to keep the combustion chamber adjacent to the combustion chamber to be replaced warm during coke oven dismantling and to insulate the space for the replacement work in the combustion chamber to be replaced; (3) a sliding scaffolding that can be attached and detached from outside the coke oven and can be connected to each other, for the purpose of preventing workers from falling and ensuring footholds during work; (4) A ceiling support beam is provided, which is made by welding and fixing a beam and an insulating structure with insulating material in contact with the existing bricks, and which prevents the existing bricks of the adjacent combustion chamber from collapsing and being insulated when the ceiling of the combustion chamber is demolished for repair by replacing it. This is considered to be a more preferable solution.

[0011] According to the coke oven repair method and repair device of the present invention, by observing the condition of the wall of the adjacent combustion chamber before dismantling the bricks of the combustion chamber to be repaired, it is possible to determine the range of oven wall bricks and binder bricks to be appropriately repaired, thereby solving the problem of the wall of the adjacent combustion chamber protruding into the coke chamber after repair.

[0012] 1A and 1B are diagrams illustrating repair when there is no overhang on the furnace wall of an adjacent combustion chamber; FIG. 1B is a diagram illustrating repair when there is no overhang on the furnace wall of an adjacent combustion chamber; FIG. 1C is a diagram illustrating repair when there is no overhang on the furnace wall of an adjacent combustion chamber; FIG. 1D is a diagram illustrating repair when there is an overhang on the furnace wall of an adjacent combustion chamber; FIG. 1E is a diagram illustrating repair when there is an overhang on the furnace wall of an adjacent combustion chamber; FIG. 1F is a diagram illustrating repair when there is an overhang on the furnace wall of an adjacent combustion chamber; and FIG. 1G is a diagram illustrating repair when there is an overhang on the furnace wall of an adjacent combustion chamber. 1G (a) and (b) are diagrams illustrating an example of a slide gate as a preferred embodiment of the coke oven repair method of the present invention; FIG. 1G (a) and (b) are diagrams illustrating an example of an insulating structure as a preferred embodiment of the coke oven repair apparatus used in the coke oven repair method of the present invention; and FIG. 1G is a diagram illustrating an example of pre-gas hole curing as a preferred embodiment of the coke oven repair method of the present invention. FIG. 1 is a diagram for explaining an example of a ceiling restraint beam as a preferred embodiment of a coke oven repair apparatus used in the coke oven repair method of the present invention. FIG. 2 is a diagram for explaining an example of a crossover MCB as a preferred embodiment of the coke oven repair method of the present invention. FIG. 3 is a diagram for explaining a state of implementation of Example 1. FIG. 4 is a diagram for explaining a state of implementation of Example 2. FIG. 5 is a diagram for explaining a state of implementation of Example 3. FIG. 6 is a diagram for explaining an example of a known coke oven. FIG. 7 is a diagram of a known coke oven viewed from above.

[0013] The following describes in detail the embodiments of the present invention. Note that the following embodiments are intended to exemplify devices and methods for embodying the technical concept of the present invention, and are not intended to limit the configuration to that described below. In other words, the technical concept of the present invention can be modified in various ways within the technical scope defined in the claims.

[0014] <Summary of the Invention> The present invention relates to a method and apparatus for repairing a coke oven, and was achieved based on the following findings. Conventional methods for repairing coke ovens have had a problem in that, when repairing a combustion chamber to be repaired, the furnace wall of the combustion chamber adjacent to the combustion chamber to be repaired overhangs the coking chamber. Furthermore, if the adjacent combustion chamber overhangs significantly, it is difficult to properly install the insulation panels, resulting in a drop in the temperature of the adjacent combustion chamber and overhanging into the coking chamber. To solve these problems, the condition of the furnace wall of the adjacent combustion chamber is observed before repairing the combustion chamber to be repaired, and the furnace wall of the adjacent combustion chamber is determined to be sound if it satisfies certain conditions. It has been discovered that by repairing the combustion chamber to be repaired when the adjacent combustion chamber is determined to be sound, the furnace wall of the adjacent combustion chamber does not overhang the coking chamber after repair.

[0015] 1A to 1C are diagrams illustrating repairs when there is no overhang on the furnace wall of an adjacent combustion chamber. First, as shown in FIG. 1A, the unevenness of the furnace wall of a combustion chamber adjacent to the combustion chamber to be repaired is observed using a three-dimensional measuring device to confirm that the overhang of the furnace wall is less than a predetermined value. Next, as shown in FIG. 1B, an insulating panel is installed on the surface of the adjacent combustion chamber facing the combustion chamber to be repaired, and the replaced portion of the combustion chamber to be repaired is dismantled. Then, as shown in FIG. 1C, the panel is replaced on the dismantled portion of the combustion chamber to be repaired, and the combustion chamber to be repaired is repaired. At this time, in the adjacent combustion chambers where the overhang of the furnace wall was confirmed to be less than the predetermined value in FIG. 1A, none of the adjacent combustion chambers has any overhang on the furnace wall, as shown in FIG. 1C.

[0016] Figures 2A to 2C are diagrams illustrating repairs when an overhang is found on the furnace wall of an adjacent combustion chamber. First, as shown in Figure 2A, the unevenness of the furnace wall of the combustion chamber adjacent to the combustion chamber to be repaired is observed using a three-dimensional measuring device. Figure 2A shows an example of an observation in which the furnace wall of the combustion chamber adjacent to the upper side of the combustion chamber to be repaired overhangs a predetermined value or more, preferably 40 mm or more, and the furnace wall of the combustion chamber adjacent to the lower side of the combustion chamber to be repaired overhangs less than a predetermined value, preferably less than 40 mm. Next, as shown in Figure 2B, an insulation panel is installed on the surface of the adjacent combustion chamber facing the combustion chamber to be repaired, and the replacement portion of the combustion chamber to be repaired is dismantled. In this case, the overhanging portion of the furnace wall of the upper combustion chamber, which overhangs 40 mm or more, gets in the way of installing the insulation panel. Then, as shown in Figure 2C, the furnace wall is replaced on the dismantled portion of the combustion chamber to be repaired, and the combustion chamber to be repaired is repaired. In this case, in the upper combustion chamber where the furnace wall overhang was confirmed to be 40 mm or more in Fig. 2A, the overhang amount after reassembly was larger than before reassembly, as shown in Fig. 2C. On the other hand, in the lower combustion chamber where the furnace wall overhang was confirmed to be less than 40 mm in Fig. 2A, the overhang amount did not change before and after reassembly, as shown in Fig. 2C.

[0017] The coke oven repair method of the present invention, achieved based on the above findings, is a method for hot repairing a coke oven combustion chamber brick by replacing two or more oven wall bricks and binder bricks from the oven mouth along the oven length, and is characterized by including: a confirmation step of observing the unevenness of the oven wall of a combustion chamber adjacent to the combustion chamber to be replaced using a three-dimensional measuring device from the oven mouth to confirm that the overhang of the oven wall of the adjacent combustion chamber is equal to or less than a predetermined value; and a re-laying step of dismantling the oven wall of the combustion chamber to be replaced 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 overhang of the oven wall of the adjacent combustion chamber is less than the predetermined value. Note that the predetermined value is preferably 40 mm.

[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 adjacent combustion chamber furnace wall will no longer protrude toward the carbonization chamber after repair.

[0019] Furthermore, the coke oven repair method of the present invention includes a step of using a preformed furnace wall refractory assembly and a preformed ceiling refractory assembly as new furnace walls and ceilings to be replaced in the combustion chamber to be replaced, as described in Patent Document 4 (Japanese Patent Publication No. 6280453). According to this embodiment, the coke oven repair method of the present invention can provide a repair method that improves the efficiency of repair work. Note that the refractory assembly referred to here refers to a firebrick block, a fired or unfired castable block, etc.

[0020] 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 portion of the combustion chamber to be replaced 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 portions 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.

[0021] According to a preferred embodiment of the coke oven repair method of the present invention, when the bricks that make up the furnace wall of the combustion chamber of a coke oven are hot repaired, the remaining bricks in the unrepaired part of the combustion chamber that is not dismantled will not protrude toward the carbonization chamber after repair.

[0022] <Preferred Embodiments of the Coke Oven Repair Method and Repair Apparatus of the Present Invention> (1) A Preferred Embodiment of the Repair Apparatus (Slide Gate): Figures 3(a) and 3(b) are diagrams illustrating an example of a slide gate as a preferred embodiment of the coke oven repair method of the present invention. Figures 3(a) and 3(b) are views of the combustion chamber seen from above, in which 1 denotes a coal car rail for a coal car that loads coal into the combustion chamber, 2-1 and 2-2 are movable slide gates that open and close opening 3 above the furnace, 4 denotes a slide gate rail for moving slide gates 2-1 and 2-2, and 5 denotes safety handrails attached to each slide gate.

[0023] The opening 3 targeted in this embodiment is formed by collapse or other causes in the ceiling of the combustion chamber to be repaired. Slide gates 2-1 and 2-2 are installed in the area to be repaired, including the opening 3 in the ceiling of the combustion chamber, and are removed after the repair is complete. The slide gates 2-1 and 2-2 are movable laterally along slide gate rails 4. By moving the slide gates 2-1 and 2-2 in opposite directions, the opening 3 is closed as shown in FIG. 3( a) when work is suspended, and is open as shown in FIG. 3( b) when work is in progress. A safety handrail 5, as shown in FIG. 3( b), is provided to prevent people or objects from falling through the opening 3 when it is open.

[0024] Normally, when the top of a coke oven is dismantled, an opening 3 is created above the oven, and people or objects may fall through the opening 3. In the coke oven repair method of the present invention, by providing the slide gates 2-1 and 2-2 of this embodiment, it is possible to effectively prevent people or objects from falling through the opening 3.

[0025] (2) Preferred embodiment of repair device (thermal insulation structure): Figures 4(a) and 4(b) are diagrams illustrating an example of a thermal insulation structure as a preferred embodiment of a coke oven repair device used in the coke oven repair method of the present invention. In Figures 4(a) and 4(b), the thermal insulation structure 11 of this embodiment is a thermal insulation structure in which several types of thermal insulation materials 13-1 and 13-2 are stacked and fixed together in an iron frame 12.

[0026] As shown in FIG. 4(b), the thermal insulation structure 11 is composed of a pair of biosoluble thermal insulation materials 13-1 and a high-performance thermal insulation material 13-2 sandwiched between the pair of biosoluble thermal insulation materials 13-1, located between a pair of iron frames 12. The high-performance thermal insulation material 13-2 has a thermal conductivity of approximately 0.003 W / mK, which is approximately 1 / 10 of the thermal conductivity of the biosoluble thermal insulation material 13-1. By using the high-performance thermal insulation material 13-2, the thickness of the thermal insulation structure 11 can be reduced. Furthermore, the high-performance thermal insulation material 13-2 is itself brittle. Therefore, sandwiching the high-performance thermal insulation material 13-2 between a pair of biosoluble thermal insulation materials 13-1 allows the high-performance thermal insulation material 13-2 to be suitably fixed. The thermal insulation structure 11 is installed only in the portion of the combustion chamber to be dismantled.

[0027] The heat insulating structure 11 of this embodiment is provided between a combustion chamber to be replaced and an adjacent combustion chamber to insulate the combustion chamber adjacent to the combustion chamber to be replaced and to insulate the space for the brick replacement work when the coke oven is dismantled. In the coke oven repair device used in the coke oven repair method of the present invention, by providing the heat insulating structure 11 of this embodiment on the surface facing the combustion chamber to be repaired outside the adjacent combustion chamber, the heat of the existing oven wall (adjacent combustion chamber) can be retained and the space for the brick replacement work can be suitably insulated.

[0028] (3) A Preferred Embodiment of the Repair Method (Preliminary Gas Hole Curing): Fig. 5 is a diagram illustrating an example of preliminary gas hole curing as a preferred embodiment of the coke oven repair method of the present invention. Fig. 5 is a view of the combustion chamber viewed from above to below, and shows that at the bottom of the combustion chamber there are an M gas (a mixed gas of blast furnace gas and coke gas) hole 21, a C gas (coke gas) hole 22, and an air hole 23. In this embodiment, it is preferable to cure these gas holes in advance before repair.

[0029] That is, with a portion of the combustion chamber furnace wall opened beforehand, the gas and air holes of the existing combustion chamber are covered with protective materials. One example of covering with a cover is to dismantle the furnace wall bricks at the bottom of the combustion chamber to be repaired and install insulation (iron plate or cloth) at the bottom of the combustion chamber before repair. Another example of covering with a cover is to fill the combustion chamber with insulation through the flue hole at the top of the combustion chamber to be repaired until it is completely filled. It is only necessary to cover the gas holes in the area corresponding to the portion of the combustion chamber to be dismantled.

[0030] In the method for repairing a coke oven according to the present invention, if the preliminary gas hole curing of the present embodiment is performed, it is possible to prevent the debris that falls during dismantling from being mixed into the regenerator chamber of the combustion chamber to be repaired, thereby suitably reducing the need for suction removal of the debris that falls into the regenerator chamber, which was previously required.

[0031] (4) A Preferred Embodiment of the Repair Apparatus (In-Oven Sliding Scaffolding): Figures 6(a) and 6(b) are diagrams illustrating an example of an in-oven sliding scaffolding as a preferred embodiment of the coke oven repair apparatus used in the coke oven repair method of the present invention. In Figures 6(a) and 6(b), 31 is a coke oven, and 32 is an in-oven sliding scaffolding installed in the coke oven. The in-oven sliding scaffolding 32 of this embodiment is a sliding scaffolding that can be attached and detached from outside the coke oven 31, with the aim of preventing a worker 33 from falling and securing a foothold during work, and has a structure that allows it to be connected and linked.

[0032] The in-furnace sliding scaffolding 32 of this embodiment is installed in the carbonization chamber of the coke oven 31 from the mouth side to create scaffolding inside the carbonization chamber and is used to ensure footing for workers. The in-furnace sliding scaffolding 32 can be connected and extended while sliding toward the furnace interior, and can also be connected and stacked in the furnace height direction. If the in-furnace sliding scaffolding of this embodiment is used as a coke oven repair device used in the coke oven repair method of the present invention, it is possible to prevent workers involved in repair work from falling and to ensure footing during work.

[0033] (5) A Preferred Embodiment of the Repair Apparatus (Ceiling Restraint Beam): Figure 7 is a diagram illustrating an example of a ceiling restraint beam as a preferred embodiment of the coke oven repair apparatus used in the coke oven repair method of the present invention. In Figure 7, the ceiling restraint beam 41 has a structure in which an insulating structure 44, which is formed by fixing insulating material 42 to an iron frame 43 and integrating it, is placed against the existing ceiling portion 45 of the coke oven, and a beam 46 is welded and fixed to the iron frame 43. The ceiling restraint beam 41 need only be formed in the portion corresponding to the portion of the combustion chamber to be dismantled.

[0034] If the ceiling support beam of this embodiment is used as a coke oven repair device for the coke oven repair method of the present invention, it is possible to effectively insulate the existing bricks and prevent them from collapsing after dismantling the ceiling of the combustion chamber to be repaired.

[0035] (6) A Preferred Embodiment of the Repair Method (Crossover MCB): Fig. 8 is a diagram illustrating an example of crossover MCBs (Module Castable Blocks) as a preferred embodiment of the coke oven repair method of the present invention. Fig. 8 shows a structure that serves as a passage for exhausting combustion exhaust gas between adjacent combustion chambers. In this embodiment, the MCB is formed of a one-piece or two-piece large precast block including a brick cavity (indicated by the arrow in Fig. 8 ), which is then stacked.

[0036] In a coke oven having a crossover MCB according to this embodiment, a pair of combustion chambers is treated as a single combustion chamber. Therefore, in this embodiment, repair work is performed not on each combustion chamber individually, but on a pair of combustion chambers formed integrally by stacking one-piece or two-piece precast blocks to repair brick cavities formed in the ceilings of adjacent combustion chambers. This makes it possible to suitably apply the coke oven repair method of the present invention to a coke oven having a crossover MCB.

[0037] <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 and coke oven repair device that uses technologies that have already become publicly known in patent publications and published publications, as exemplified below.

[0038] As described in Patent Document 2 (JP 2022-110682 A), the coke oven repair method of the present invention preferably includes a step of installing an insulating panel by loading the insulating panel onto a transport vehicle and pulling it with a towing wire into a predetermined coking chamber and stopping it, or by pushing it out with a pusher and stopping it, before dismantling the portion of the combustion chamber that needs repair to be transferred. According to this embodiment, in the coke oven repair method of the present invention, when repairing the entire length of the combustion chamber wall from the pusher side to the fire extinguisher car side of the coke oven, an insulating wall to protect workers can be installed inside the oven in a short period of time and at low cost.

[0039] As described in Patent Document 3 (Japanese Patent No. 6,587,951), the coke oven repair method of the present invention preferably includes a step of using a demolition heavy equipment cart when dismantling the portion of the combustion chamber to be reloaded that requires repair. According to this embodiment, in the coke oven repair method of the present invention, the demolition heavy equipment can be easily transported to the location where the walls and ceiling of the coke oven combustion chamber are to be dismantled. As a result, the demolition work can be carried out efficiently and safely, and the construction period and construction costs can be shortened.

[0040] In the method for repairing a coke oven of the present invention, as described in Patent Document 5 (Japanese Patent No. 6482484), it is preferable to include a step of using a cart that travels across the furnace to transport the furnace wall refractory assemblies and the ceiling refractory assemblies. According to this embodiment, in the method for repairing a coke oven of the present invention, it is possible to efficiently transport modular blocks for constructing new walls and ceilings of the combustion chamber of the coke oven to the repair work site, and further to easily and safely carry the modular blocks and castable blocks into the furnace.

[0041] As described in Patent Document 6 (Japanese Patent No. 6502435), the coke oven repair method of the present invention preferably includes the steps of positioning the oven wall refractory assemblies and the ceiling refractory assemblies horizontally using a laser beam and installing spacers to maintain a uniform mortar joint thickness when arranging them horizontally. According to this embodiment, the coke oven repair method of the present invention can prevent deformation or collapse of the wall constructed by stacking modular blocks.

[0042] As described in Patent Document 7 (Japanese Patent No. 6502436), the method for repairing a coke oven of the present invention preferably includes a step of installing a ceiling refractory assembly when forming a new ceiling to be replaced, and then pouring casters into gaps around the ceiling refractory assembly to fill them. According to this embodiment, the method for repairing a coke oven of the present invention can repair the ceilings of the coking chamber and combustion chamber of the coke oven efficiently and in a short time.

[0043] In the coke oven repair method of the present invention, as described in Patent Document 8 (JP 2017-137447 A), it is preferable to divide the wall forming the combustion chamber into multiple blocks and integrally mold them out of monolithic refractory to preliminarily fabricate integrally molded blocks, dismantle the wall and transport it outside the furnace, then carry in the integrally molded blocks and abut their ends against two surfaces arranged perpendicular to the ends of the existing wall to construct a new wall. According to this embodiment, the coke oven repair method of the present invention enables efficient repair work of the coke oven combustion chamber, thereby shortening the construction period, reducing the workload, improving safety, and increasing the durability of the repaired structure.

[0044] Example 1 As shown in Figure 9, for a combustion chamber to be repaired and two combustion chambers adjacent to the combustion chamber to be repaired that constitute a coke oven, the unevenness of the furnace walls was measured using a laser scanner at predetermined positions on the kiln mouth bricks of the adjacent combustion chambers before and after they were re-laid on the combustion chamber to be repaired. In addition, before the combustion chamber to be repaired was re-laid, the presence or absence of cracks was observed through the flue hole. The results are shown in Table 1 below.

[0045]

[0046] The results in Table 1 show that if the kiln mouth overhang of the adjacent combustion chamber before re-stacking is +40 mm, this will be exacerbated after re-stacking, so the kiln mouth overhang of the adjacent combustion chamber before re-stacking must be less than +40 mm. Furthermore, if the overhang is ≦15 mm, there will be almost no change after re-stacking (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 inside the flue hole.

[0047] Example 2 As shown in Figure 10, in an example in which kiln mouth extension prevention bricks were placed between a combustion chamber to be repaired and two combustion chambers adjacent to the combustion chamber to be repaired, the unevenness of the oven wall was measured using a laser scanner at predetermined positions on the kiln mouth bricks of the adjacent combustion chambers before and after the combustion chamber to be repaired was replaced. In addition, before the combustion chamber to be repaired was replaced, the presence or absence of cracks was observed through the flue hole. The results are shown in Table 2 below.

[0048]

[0049] The results in Table 2 show that installing anti-bulge bricks at the kiln mouth suppresses bulging after reloading. However, if the bulge amount is +40 mm, it is difficult to suppress further bulging even with the anti-bulge bricks.

[0050] Example 3 As shown in Figure 11, a case was investigated in which a combustion chamber was to be replaced (repaired) and a portion of the combustion chamber was left intact. For this example, kiln-mouth extension prevention bricks were placed between the combustion chamber to be partially repaired and the two combustion chambers adjacent to the combustion chamber to be repaired. Before and after the replacement of the combustion chamber to be repaired, the unevenness of the oven wall was measured using a laser scanner at a predetermined position on the kiln-mouth bricks of the adjacent combustion chambers. Furthermore, before the replacement of the combustion chamber to be repaired, the presence or absence of cracks was observed through the flue hole. The results are shown in Table 3 below.

[0051]

[0052] The results in Table 3 show that if there are cracks in the remaining combustion chamber (old bricks), the furnace wall will protrude after replacement (even if that part does not protrude).The above results also show that it is difficult to prevent this, regardless of whether or not protrusion prevention bricks are installed.

[0053] The coke oven repair method and repair device of the present invention can determine the range of oven wall bricks and binder bricks to be appropriately repaired by observing the condition of the wall of the adjacent combustion chamber before dismantling the bricks of the combustion chamber to be repaired. This solves the problem of the wall of the adjacent combustion chamber protruding into the coke chamber after repair, and is therefore industrially useful.

[0054] 1 Coal loading car rail 2-1, 2-2 Slide gate 3 Opening 4 Slide gate rail 5 Safety handrail 11 Heat insulating structure 12 Iron frame 13-1 Biosoluble heat insulating material 13-2 High performance heat insulating material 21 M gas (mixed gas of blast furnace gas and coke gas) hole 22 C gas (coke gas) hole 23 Air hole 31 Coke oven 32 Sliding scaffolding inside the furnace 33 Worker 41 Ceiling support beam 42 Heat insulating material 43 Iron frame 44 Heat insulating structure 45 Ceiling 46 Beam 51 Carbonization chamber 52 Combustion chamber 53 Regenerator 54 Coal loading port 55 Coal loading car 56 Pusher 56a Push-out ram 57 Guide car 58 Fire extinguishing car 59 Flue (vertical flame duct) 60 Backstay

Claims

1. A method of repairing a coke oven in which two or more oven wall bricks and binder bricks are hot-replaced from the oven mouth along the oven length, the method comprising: a confirmation step of observing the unevenness of the oven wall of a combustion chamber adjacent to the combustion chamber to be replaced with a three-dimensional measuring device from the oven mouth to confirm that the amount of protrusion of the oven wall of the adjacent combustion chamber is less than a predetermined value; a re-stacking step of dismantling the portion of the oven wall of the combustion chamber to be replaced that needs repair and stacking new oven wall bricks and binder bricks in the dismantled area when it is confirmed in the confirmation step that the amount of protrusion of the oven wall of the adjacent combustion chamber is less than a predetermined value; and a step of using a pre-formed oven wall refractory assembly and a pre-formed roof refractory assembly as the newly replaced oven wall and ceiling of the combustion chamber to be replaced.

2. The method for repairing a coke oven as set forth in claim 1, wherein said predetermined value is 40 mm.

3. 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 portion of the combustion chamber to be replaced that requires repair; and a step of further checking the convex portions 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.

4. A coke oven repair device used in the repair method according to any one of claims 1 to 3, characterized in that it comprises a slide gate provided on the top of the coke oven, the slide gate being capable of moving laterally to open when the coke oven is dismantled and to close when the coke oven dismantling work is suspended, the slide gate being provided with safety handrails around it, in relation to an opening that is generated when the coke oven top is dismantled.

5. A coke oven repair device used in the repair method according to any one of claims 1 to 3, characterized in that it comprises an insulating structure in which several types of insulating materials are layered and fixed together within an iron frame, and which is provided between a combustion chamber to be transferred and an adjacent combustion chamber in order to retain heat in the combustion chamber adjacent to the combustion chamber to be transferred and to insulate the space for the transfer work in the combustion chamber to be transferred when the coke oven is dismantled.

6. A method for repairing a coke oven as described in any one of claims 1 to 3, characterized in that, with a portion of the combustion chamber wall opened in advance, the gas holes and air holes of the existing combustion chamber are covered with covering materials, or insulating material is filled in through the flue hole at the top of the combustion chamber wall to cover the gas holes and air holes, thereby preventing fallen debris from getting into the heat regenerator when the combustion chamber is dismantled and replaced.

7. A coke oven repair device used in the repair method according to any one of claims 1 to 3, characterized in that it is equipped with a sliding scaffolding that can be attached and detached from outside the coke oven and that can be connected together to prevent workers from falling and to ensure a foothold during work.

8. A coke oven repair device used in the repair method according to any one of claims 1 to 3, characterized in that the device is equipped with a ceiling restraint beam formed by welding and fixing a beam and an insulating structure with insulating material placed against the existing bricks, and which prevents the existing bricks of an adjacent combustion chamber from being insulated and collapsing when the ceiling of the combustion chamber to be repaired is dismantled by replacing it.

9. A method for repairing a coke oven as claimed in any one of claims 1 to 3, characterized in that repair work is carried out on a pair of combustion chambers which are formed integrally by stacking one-piece or two-piece precast blocks to replace brick cavities formed in the ceilings of adjacent combustion chambers.

10. A method for repairing a coke oven as described in any one of claims 1 to 3, characterized in that it includes a step of installing an insulating panel by placing the insulating panel on a transport cart and pulling it with a towing wire into a designated carbonization chamber and stopping it, or by pushing it out with a pusher and stopping it, before dismantling the portion of the combustion chamber that is to be transferred that requires repair.

11. A method for repairing a coke oven as described in any one of claims 1 to 3, comprising a step of using a demolition heavy machinery cart when dismantling the portion of the combustion chamber to be transferred that requires repair.

12. A method for repairing a coke oven as claimed in any one of claims 1 to 3, characterized in that it includes a step of using a cart that travels across the oven to transport and carry in the oven wall refractory assembly and the oven ceiling refractory assembly.

13. A method for repairing a coke oven as described in any one of claims 1 to 3, comprising the steps of: positioning the oven wall refractory assembly and the ceiling refractory assembly horizontally using a laser beam when arranging them horizontally; and installing spacers to maintain a constant mortar joint thickness.

14. A method for repairing a coke oven as claimed in any one of claims 1 to 3, comprising the steps of: when forming a new ceiling to be replaced, installing the ceiling refractory assembly, and pouring casters into the gaps around the ceiling refractory assembly to fill them.

15. A method for repairing a coke oven as described in any one of claims 1 to 3, characterized in that the wall forming the combustion chamber is divided into a plurality of blocks, and one-piece molded blocks are fabricated in advance by molding the blocks integrally out of amorphous refractory material, and after the wall is dismantled and carried out of the oven, the one-piece molded blocks are brought in and positioned so that their ends abut against two faces that are arranged at right angles to the ends of the existing wall, thereby constructing the new wall.

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