Method and apparatus for repairing coke oven

Abstract

This method for repairing a coke oven comprises: a confirmation step for observing, by using a three-dimensional measuring instrument from an oven port, the unevenness of a furnace wall of an adjacent non-replacement combustion chamber adjacent to one side surface of one replacement combustion chamber or a plurality of contiguous replacement combustion chambers, and of a furnace wall of an adjacent non-replacement combustion chamber adjacent to the other side surface, and confirming that the protruding amount of each of the furnace walls of the adjacent non-replacement combustion chambers is less than a prescribed value; a replacement step for, when it is confirmed in the confirmation step that the protruding amount of each of the furnace walls of the adjacent non-replacement combustion chambers is less than the prescribed value, dismantling a portion requiring repair of a furnace wall of the one replacement combustion chamber or the plurality of contiguous replacement combustion chambers, and stacking new furnace wall bricks and binder bricks in the dismantled range; and a step for using a furnace wall refractory aggregate molded in advance and a ceiling part refractory aggregate molded in advance as the furnace wall and a ceiling part for replacement to be new in the replacement combustion chamber.

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 Figure 13, 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 loading ports 54 are used to load coal carried by a coal loading car 55 traveling above the coke oven into the coking chamber 51. The coal loaded into the coking chamber 51 through the 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 quencher 58 via a guide car 57, and transported by the fire quencher 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 14, 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 13) of the extruder 56 is inserted, and a kiln opening from which the red-hot coke is extruded. Backstays 60 (see Figure 14) 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 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 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 and apparatus for repairing coke ovens, which, when hot repairing the bricks that make up the walls of a coke oven combustion chamber, prevents the remaining bricks in an adjacent non-replaced combustion chamber that does not require repair and the remaining bricks in the non-repaired portion that remains 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 bricks of one combustion chamber or bricks of multiple consecutive combustion chambers constituting the coke oven from the kiln mouth along the direction of the furnace length with two or more oven wall bricks and binder bricks, and the method includes 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 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, and determining whether the amount of protrusion of each oven wall of the adjacent non-replacement combustion chamber is less than a predetermined value. a transfer step of demolishing the portion of the furnace wall of one transfer combustion chamber or a plurality of consecutive transfer combustion chambers that needs repair and laying new furnace wall bricks and binder bricks in the demolished area when it is confirmed in the confirmation step that the amount of protrusion of the furnace wall of the adjacent non-replacement combustion chamber is less than a predetermined value; and a step of using a pre-formed furnace wall refractory assembly and a pre-formed ceiling refractory assembly as the newly replaced furnace wall and ceiling of the transfer combustion chamber.

[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 impede normal operation is 5%, and by calculating d from the formula (1), the predetermined value of the amount of overhang is 40 mm, (3) before dismantling the area of ​​the transfer combustion chamber that needs repair, the process includes a repair range determination step of determining the range of oven wall bricks and binder bricks that need repair by observing the unevenness of the oven wall from the kiln opening with a three-dimensional measuring device, and a step of further confirming the convex parts of the oven 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 opening than the binder bricks that have been determined to be sound, (4) With a portion of the combustion chamber furnace wall opened in advance, the gas holes and air holes of the existing combustion chamber are covered with a covering material, or the gas holes and air holes are covered by filling the heat insulating material through the flue holes at the top of the combustion chamber furnace wall, thereby preventing falling debris from entering the regenerator when the transfer combustion chamber is dismantled; (5) 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; (6) Installing an insulation panel by placing it on a transport cart and pulling it with a towing wire into a specified carbonization chamber and stopping it, or by pushing it out with a pusher and stopping it, before dismantling the part of the transfer combustion chamber that needs repair; (7) Using a demolition heavy equipment cart when dismantling the part of the transfer combustion chamber that needs repair; (8) The method includes a step of using a cart that travels across the furnace to transport and carry in the furnace wall refractory assemblies and the ceiling refractory assemblies; (9) The method includes a step of positioning the furnace wall refractory assemblies and the ceiling refractory assemblies horizontally with a laser beam and a step of installing spacers to make the mortar joint thickness uniform when arranging the furnace wall refractory assemblies and the ceiling refractory assemblies horizontally; (10) The method includes a step of installing the ceiling refractory assemblies and further pouring casters into the gaps around the ceiling refractory assemblies to fill them when forming a new ceiling to be replaced;(11) A more preferable solution is considered to be to divide the wall forming the combustion chamber into a plurality of blocks and to fabricate integrally molded blocks out of amorphous refractory in advance, dismantle the wall and transport it outside the furnace, then bring in the integrally molded blocks and position them so that their ends abut against two surfaces that are perpendicular to the ends of the existing wall, thereby constructing the new wall.

[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, which is provided between the transfer combustion chamber and the adjacent non-transfer combustion chamber adjacent thereto in order to retain heat in the adjacent non-transfer combustion chamber adjacent to the transfer combustion chamber and to insulate the space for transfer work in the transfer combustion chamber when the coke oven is dismantled; (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 more preferable solution would be to provide a ceiling support beam that is made by welding and fixing a beam and an insulating structure with insulating material in contact with the existing bricks, and that prevents the insulation and collapse of the existing bricks of the adjacent non-replacement combustion chamber when the ceiling of the replacement combustion chamber to be repaired is dismantled.

[0011] According to the coke oven repair method and repair device 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.

[0012] 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 repair when there is an overhang on the furnace wall of an adjacent non-transferring combustion chamber; FIG. 7 is a diagram for explaining repair when there is an overhang on the furnace wall of an adjacent non-transferring combustion chamber; FIG. 8 is a diagram for explaining repair when there is an overhang on the furnace wall of an adjacent non-transferring combustion chamber; 1A and 1B are diagrams illustrating an example of an in-oven sliding scaffold as a preferred embodiment of a coke oven repair apparatus used in the coke oven repair method of the present invention; FIG. 1B is a diagram illustrating 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. 1C is a diagram illustrating an example of a crossover MCB as a preferred embodiment of the coke oven repair method of the present invention; FIG. 1D is a diagram illustrating a state of implementation of Example 1; FIG. 1E is a diagram illustrating a state of implementation of Example 2; FIG. 1F is a diagram illustrating a state of implementation of Example 3; FIG. 1F is a graph showing the relationship between the jamming rate and the overhang amount obtained when the coal loading amount is 30 t, which is full loading; FIG. 1G is a diagram illustrating an example of a known coke oven; FIG. 1H 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 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 meets 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.

[0015] 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.

[0016] 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.

[0017] 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.

[0018] 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.

[0019] 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.

[0020] Furthermore, the coke oven repair method of the present invention includes a step of using a preformed oven wall refractory assembly and a preformed ceiling refractory assembly as newly replaced oven walls and ceilings in a replacement combustion chamber, as described in Patent Document 4 (Japanese Patent 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.

[0021] 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.

[0022] 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.

[0023] <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.

[0024] The opening 3 targeted in this embodiment is formed by collapse or other factors in the ceiling of the transfer 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 transfer combustion chamber to be repaired, 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.

[0025] 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.

[0026] (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.

[0027] As shown in FIG. 4B, 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 transfer combustion chamber to be dismantled.

[0028] The heat insulating structure 11 of this embodiment is provided between a transfer combustion chamber and an adjacent non-transfer combustion chamber to insulate the adjacent non-transfer combustion chamber adjacent to the transfer combustion chamber and to insulate the space for transfer work in the transfer combustion chamber during coke oven dismantling. 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 transfer combustion chamber to be repaired outside the adjacent non-transfer combustion chamber, it is possible to insulate the heat of the existing oven wall (adjacent combustion chamber) and suitably insulate the space for brick transfer work.

[0029] (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.

[0030] 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 a covering material. One example of covering with a covering is to dismantle the furnace wall bricks at the bottom of the combustion chamber to be repaired and install insulation material (iron plate or cloth) at the bottom of the combustion chamber before repair. Another example of covering with a covering is to fill the combustion chamber with insulation material through the flue hole at the top of the replacement combustion chamber to be repaired until it is completely filled. It is only necessary to cover the gas hole in the area corresponding to the part of the replacement combustion chamber to be dismantled.

[0031] 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.

[0032] (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.

[0033] 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.

[0034] (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 transfer combustion chamber to be dismantled.

[0035] 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.

[0036] (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.

[0037] 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.

[0038] <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.

[0039] 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 transfer combustion chamber that needs repair, by installing the insulating panel. 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.

[0040] 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 transfer combustion chamber 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.

[0041] 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.

[0042] 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.

[0043] 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.

[0044] 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.

[0045] <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.

[0046] 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, Fig. 12 is a graph showing the relationship between the clogging rate and the overhang amount based on the data in Table 1.

[0047]

[0048] From the results of Table 1 and FIG. 12, the following formula (1) was obtained by regression analysis: Jamming rate (%) = 5 × 10 －８ ×d ５ ...(1) where d (mm) is the amount of overhang.

[0049] 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.

[0050] 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.

[0051] Example 1 As shown in Figure 9, 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 make up 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.

[0052]

[0053] 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.

[0054] Example 2 As shown in Figure 10, 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, 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) before and after the combustion chamber (replacement combustion chamber) to be repaired was replaced. In addition, before the combustion chamber (replacement 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 3 below.

[0055]

[0056] The results in Table 3 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.

[0057] Example 3: As shown in Figure 11, 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) that was partially to be 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.

[0058]

[0059] 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.

[0060] In the coke oven repair method and repair device 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.

[0061] 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 the bricks of one combustion chamber or the bricks of multiple consecutive combustion chambers constituting 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-replacement 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-replacement 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 said adjacent non-replacement combustion chambers is less than a predetermined value; and a re-stacking 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 stacking 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 said adjacent non-replacement combustion chamber is less than the predetermined value; and using a preformed furnace wall refractory assembly and a preformed ceiling refractory assembly as the furnace wall and ceiling to be newly replaced in the replacement combustion chamber.

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 coke oven repair device used in the repair method according to any one of claims 1 to 4, 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.

6. A coke oven repair device used in the repair method according to any one of claims 1 to 4, characterized in that it comprises an insulating structure made by stacking and fixing several types of insulating materials inside an iron frame and integrating them, the insulating structure being provided between a transfer combustion chamber and an adjacent non-transfer combustion chamber adjacent thereto in order to retain heat in the adjacent non-transfer combustion chamber adjacent to the transfer combustion chamber and to insulate the space for transfer work in the transfer combustion chamber when the coke oven is dismantled.

7. A method for repairing a coke oven as described in any one of claims 1 to 4, 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 storage chamber when the replaced combustion chamber is dismantled.

8. A coke oven repair device used in the repair method according to any one of claims 1 to 4, 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.

9. A coke oven repair device used in the repair method according to any one of claims 1 to 4, characterized in that the device is provided with a ceiling restraint beam formed by welding and fixing a beam and an insulating structure with insulating material in contact with the existing bricks, and which prevents the insulation and collapse of the existing bricks of an adjacent non-replacement combustion chamber when dismantling the ceiling of the replacement combustion chamber to be repaired.

10. A method for repairing a coke oven as claimed in any one of claims 1 to 4, characterized in that repair work is carried out on a pair of combustion chambers formed integrally by stacking one-piece or two-piece precast blocks to replace brick cavities formed in the ceilings of adjacent combustion chambers.

11. A method for repairing a coke oven as described in any one of claims 1 to 4, 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 specified carbonization chamber and stopping it, or by pushing it out with a pusher and stopping it, before dismantling the portion of the transfer combustion chamber that needs repair.

12. A method for repairing a coke oven as described in any one of claims 1 to 4, comprising the step of using a demolition heavy machinery dolly when dismantling the portion of the transfer combustion chamber that requires repair.

13. A method for repairing a coke oven as claimed in any one of claims 1 to 4, 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.

14. A method for repairing a coke oven as claimed in any one of claims 1 to 4, 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.

15. A method for repairing a coke oven as described in any one of claims 1 to 4, characterized in that it includes a step of: when forming a new ceiling section to be replaced, installing the ceiling section refractory assembly, and pouring casters into and filling the gaps around the ceiling section refractory assembly.

16. A method for repairing a coke oven as described in any one of claims 1 to 4, 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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