Method for repairing oven wall of coke oven

Abstract

Provided is a method that is for repairing an oven wall of a coke oven and that is capable of repairing the oven wall while taking into account the time required for repairing the oven wall.　This method that is for repairing an oven wall of a coke oven and that repairs an oven wall of a carbonization chamber included in the coke oven comprises: an obtaining step for obtaining an oven wall profile by measuring the unevenness of the oven wall; a repair plan-creation step for creating a repair plan for repairing the unevenness; a modifying step for modifying the oven wall profile in accordance with the repair plan; an extrusion force estimation step for estimating, by using the modified oven wall profile, an extrusion force for extruding a coke cake in the carbonization chamber by means of an extruder; a repair time calculation step for calculating the time required for executing the repair plan; and a repairing step for repairing the oven wall in accordance with the repair plan.

Description

Coke oven wall repair method

[0001] The present invention relates to a method for repairing a coke oven wall, which calculates the time required for the repair.

[0002] In the steel industry, coke ovens are used to produce coke from coal. In recent years, many coke ovens have become obsolete, having been built 40 years ago or more. Coke ovens are constructed by stacking bricks bonded with a thin layer of mortar, and then clamping them from the front, back, left, and right to maintain their shape. A coke oven has a heat storage chamber on top of the foundation, and above that are carbonization chambers about 6 m high, 400 mm wide, and 16 m deep, and combustion chambers about 900 mm wide for burning fuel gas, arranged alternately in the width direction, with a brick ceiling above.

[0003] In a coke oven, the heat from burning fuel inside the combustion chamber passes through the wall bricks of the combustion chamber, raising the temperature inside the coke oven to over 1000°C. Coal is then introduced through a coal loading hole at the top of the coke oven chamber, and the coal is carbonized to produce coke. The coke cake after carbonization is extruded by inserting an extruder into one of the kiln openings, which are about 6 m high and 400 mm wide at both ends of the coke oven chamber, and is then removed from the other opening. After construction is complete, fuel is burned inside the coke oven, gradually raising the temperature of the bricks to over 1000°C. This brick temperature is maintained until the coke oven is shut down.

[0004] The wall bricks separating the combustion chamber from the coke chamber are called the oven wall, and they serve the roles of preventing combustion gases from entering the coke chamber, transferring combustion heat to the coke chamber, and supporting the ceiling. The oven wall is constantly subjected to a ceiling load and oven clamping force, and when the coke cake is extruded, the pusher load and extrusion friction force act temporarily. The ceiling load and oven clamping force serve to stabilize the oven wall structure, but as a coke oven ages, problems occur, such as gouges, where bricks wear down over a wide area of ​​the oven wall and become thinner, and overhangs, where bricks fall and protrude into the coke chamber.

[0005] When such problems occur, the application of clamping and pushing forces to the furnace wall can cause bricks to collapse. Furthermore, if unevenness occurs on the furnace wall due to cave-ins, protrusions, etc., the distance between the left and right furnace wall surfaces of the coke chamber (furnace width) changes from the designed dimensions, increasing the pushing force of the extruder. If the pushing force becomes too high, it becomes difficult to transport the coke cake from the coke chamber, resulting in a phenomenon known as "pushing stop" or "clogging." The occurrence of pushing stop and clogging can lead to a decrease in the extrusion cycle of the extruder, significantly reducing productivity.

[0006] As a technique for estimating the pushing force of an extruder, Patent Documents 1 and 2 disclose a method for obtaining a furnace wall profile of a coke oven using a laser-type three-dimensional shape measuring device and estimating the pushing force of a coke cake using the obtained furnace wall profile. Furthermore, Patent Documents 1 and 2 disclose a coke oven repair method for identifying a repair location on the oven wall that can reduce the pushing force using the method for estimating the pushing force and repairing the identified repair location.

[0007] Patent No. 5590270 Patent No. 6699616

[0008] In furnace wall repair based on pushing force, all irregularities on the furnace wall must often be smoothed out, which can take a long time. The present invention has been made in view of the problems of the prior art, and its object is to provide a coke oven furnace wall repair method that can carry out furnace wall repair while taking into account the time required for furnace wall repair.

[0009] The gist of the present invention, which can solve the above-mentioned problems, is as follows: [1] A coke oven wall repair method for repairing a wall of a coking chamber that constitutes a coke oven, the method comprising: an acquisition step of measuring unevenness of the oven wall to acquire a oven wall profile, a repair plan creation step of creating a repair plan for repairing the unevenness, a correction step of correcting the oven wall profile to correspond to the repair plan, an extrusion force estimation step of estimating a pushing force with which a coke cake in the coking chamber is pushed out by an extruder using the corrected oven wall profile, a repair time calculation step of calculating a time required to execute the repair plan, and a repair step of repairing the oven wall in accordance with the repair plan. [2] The coke oven wall repair method according to [1], wherein the acquisition step further estimates the pushing force using the acquired oven wall profile. [3] The coke oven wall repair method according to [1] or [2], wherein, in the acquisition step, the oven wall profile is acquired by irradiating the oven wall with laser light from a laser-type three-dimensional shape measuring device. [4] The coke oven wall repair method according to [3], wherein, in the repair plan creation step, the oven wall profile is acquired by irradiating each of the left and right oven walls of the coke oven chamber with laser light. [5] The coke oven wall repair method according to any of [1] to [4], wherein, in the repair plan creation step, a repair plan for repair work that results in a large decrease in pushing force per repair work hour is created with priority from among a repair plan for cutting a convex portion of the oven wall and a repair plan for filling a concave portion of the oven wall. [6] The method for repairing a coke oven wall according to any one of [1] to [5], wherein, when there is a portion where the oven width is narrower than a predetermined width due to a convex portion of the oven wall, the repair plan creation step creates a repair plan to cut the convex portion of the oven wall until the oven width is equal to or greater than the predetermined width before creating a repair plan to fill in the concave portion of the oven wall. [7] The method for repairing a coke oven wall according to any one of [1] to [6], wherein the pushing force estimating step further determines whether the estimated pushing force is equal to or less than a target value of the pusher, and changes the repair plan if the estimated pushing force is greater than the target value.[8] A coke oven wall repair method described in any one of [1] to [7], wherein the repair time calculation step further determines whether the calculated time is within a predetermined target time, and if the calculated time is longer than the target time, changes the repair plan.

[0010] According to the present invention, before repairing the coke chamber wall of a coke oven, the time required for the repair is calculated and the pushing force of the coke cake after the repair is estimated, so that the repair can be carried out taking into account the time required for the repair and the pushing force after the repair. As a result, the repair of the coke chamber wall can be carried out by achieving a good balance between the repair time and the pushing force in accordance with the condition of the coke oven, without spending a lot of time on the repair.

[0011] FIG. 1 is a plan view showing one coking chamber constituting a coke oven. FIG. 2 is a cross-sectional view showing a state in which a coke cake is pushed out of a coking chamber whose oven wall has been deformed due to aging. FIG. 3 is a flow diagram illustrating a coke oven wall repair method according to this embodiment. FIG. 4 is a diagram illustrating a configuration example of a push-out force estimation device. FIG. 5 is a graph showing an example of the push-out force of a coke cake estimated by the push-out force estimation device. FIG. 6 is a flow diagram illustrating another embodiment of a coke oven wall repair method according to this embodiment. FIG. 7 is a diagram showing an oven wall profile before oven wall repair and an estimated value of the push-out force of the coke cake. FIG. 8 is a diagram showing an oven wall profile corrected by an oven wall repair plan and an estimated value of the push-out force of the coke cake. FIG. 9 is a diagram showing an oven wall profile corrected by an oven wall repair plan and an estimated value of the push-out force of the coke cake. FIG. 10 is a diagram showing an oven wall profile corrected by an oven wall repair plan and an estimated value of the push-out force of the coke cake.

[0012] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The following embodiments show preferred examples of the present invention, and the present invention is not limited to these examples.

[0013] FIG. 1 is a plan view showing one coke chamber 10 constituting a coke oven. The coke chamber 10 is configured by being partitioned from an adjacent combustion chamber by oven walls 12, 14. Coal is charged into the coke chamber 10 and carbonized therein to form a coke cake 16. The coke cake 16 is pushed in an extrusion direction A1 by an extruder 18 inserted from the machine side (lower side in FIG. 1 , hereinafter sometimes referred to as "MS") of the coke oven and carried out to a guide car (not shown) waiting on the coke side (upper side in FIG. 1 , hereinafter sometimes referred to as "CS") on the opposite side of the machine side across the coke chamber 10. The inner wall surfaces of the oven walls 12, 14 are formed in a tapered shape so that the oven width of the CS is wider than that of the MS to make it easier to push the coke cake 16 out of the coke chamber 10.

[0014] In such a coke oven, when the coke oven is first constructed, the oven walls 12, 14 are not deformed, so the tapered shape of the inner wall surface is maintained, and the width of the coke cake 16 becomes narrower than the oven width in the process of being extruded in the extrusion direction A1. Therefore, the coke cake 16 is extruded without contacting any side position with the oven walls 12, 14.

[0015] On the other hand, as the coking chamber 10 deteriorates, the oven walls 12, 14 are deformed, causing irregularities. Deformations of the oven walls due to deterioration include gouges (hereinafter, gouges may be referred to as "concave portions"), which are thinning of the inner wall surface of the oven wall, and overhangs (hereinafter, overhangs may be referred to as "convex portions"), which are caused by bricks falling and protruding into the coking chamber.

[0016] 2A and 2B are cross-sectional views showing a state in which a coke cake 16 is extruded from a coke chamber 10 whose oven walls have been deformed due to aging. As shown in Fig. 2A and 2B, when the oven walls 12, 14 are deformed due to aging, the outer shape of the coke cake 16 conforms to the inner wall surfaces of the deformed oven walls 12, 14. That is, if a recess exists on the inner wall surfaces of the oven walls 12, 14, a protrusion is formed in the coke cake 16 at that position, and if a protrusion exists on the inner wall surfaces of the oven walls 12, 14, a recess is formed in the coke cake 16 at that position.

[0017] In such an aged coke chamber 10, in the process of pushing the coke cake 16, where the width of the coke cake 16 passing through is wider than the width of the coke chamber 10, the coke cake 16 is compressed and pushed out due to the narrower width, resulting in a larger pushing force of the coke cake 16. When the oven walls 12, 14 of the coke chamber 10 are deformed in this way, the pushing force of the pusher 18 on the coke cake 16 increases. If the pushing force of the coke cake 16 becomes too large, a phenomenon known as push-out or clogging occurs, in which it becomes difficult to push the coke cake 16 out of the coke chamber 10. The occurrence of push-out or clogging leads to a decrease in the extrusion cycle of the coke cake 16 and significantly reduces productivity. For this reason, it is necessary to repair the oven walls of the coke chamber 10 before the pushing force of the pusher 18 becomes too large, thereby suppressing an increase in the pushing force of the pusher 18 on the coke cake 16.

[0018] In the coke oven wall repair method according to this embodiment, when repairing the oven walls 12, 14 that have deteriorated and formed irregularities as described above, first, an oven wall repair plan is created based on the oven wall profile of the coke oven chamber 10. Next, the pushing force of the coke cake 16 after the oven wall has been repaired according to the repair plan is estimated, and the time required to execute the created repair plan is calculated. This prevents a large amount of time from being spent on repairing the oven wall of the coke oven chamber 10, and allows the oven wall of the coke oven chamber to be repaired by achieving a good balance between the oven wall repair time and the pushing force in accordance with the condition of the coke oven.

[0019] Fig. 3 is a flow diagram illustrating a coke oven wall repair method according to this embodiment. Each step of the coke oven wall repair method according to this embodiment will be described using Fig. 3. In the coke oven wall repair method according to this embodiment, first, a wall profile of the coking chamber 10 to be repaired is acquired (step S101). This process is the acquisition step. The wall profile of the coking chamber 10 is created, for example, by a laser-type three-dimensional shape measurement device.

[0020] The laser-type three-dimensional shape measuring device irradiates the inner wall surfaces of the oven walls 12, 14 of the coking chamber 10 with laser light to measure the uneven shape of the inner wall surfaces and create an oven wall profile of the coking chamber 10. The laser-type three-dimensional shape measuring device 40 preferably performs measurement by irradiating each of the left and right oven walls 12, 14 with laser light. This allows the incident angle of the laser light to be large with respect to the oven walls 12, 14, so that the uneven shape of the oven walls can be measured even if convex portions are formed on the inner wall surfaces of the oven walls 12, 14. Alternatively, the laser-type three-dimensional shape measuring device 40 may store initial profile data of the oven walls 12, 14 of the coking chamber 10 at the time of construction, and create an oven wall profile that indicates the amount of unevenness of the inner wall surfaces based on the initial shape. The oven wall profile that indicates the amount of unevenness of the inner wall surfaces based on the initial shape is created by comparing the oven wall profile created by measurement with the initial profile data at the time of construction.

[0021] Once the furnace wall profile is acquired, a furnace wall repair plan is created using the acquired furnace wall profile (step S102). This process is the repair plan creation step. In the repair plan creation step, the acquired furnace wall profile is used to determine the positions and volumes for filling in the recesses in the furnace walls 12, 14, the positions and volumes for cutting out the protrusions in the furnace walls 12, 14, and the work sequence. Here, the thermal spraying work for smoothing out the recesses in the furnace walls and the cutting work for smoothing out the protrusions in the furnace walls by sandblasting both generate a large amount of dust inside the coking chamber 10, so the two works cannot be performed in parallel. Furthermore, ３ The time required to fill the recess by thermal spraying is 1 m ３The time required for sandblasting the convex portions of the oven wall is shorter than that required for sandblasting the convex portions of the oven wall, and the amount of decrease in extrusion force per repair work hour is greater. Therefore, in the repair plan creation step, it is preferable to first create a repair plan for filling the concave portions of the oven wall, which has a larger amount of decrease in extrusion force per repair work hour. Then, if the extrusion force does not fall below the target level even after filling and smoothing the concave portions, it is preferable to create a repair plan for sandblasting the convex portions of the oven wall. This makes it possible to reduce the extrusion force of the coke cake to the target level while preventing the oven wall repair time from becoming longer. The target extrusion force is determined based on the extrusion force that causes coke sticking or clogging. If the amount of decrease in extrusion force per repair work hour is greater for repairs that involve sandblasting the convex portions of the oven wall than for repairs that involve sandblasting the concave portions of the oven wall, the repair plan for sandblasting the convex portions of the oven wall can be created with priority.

[0022] Furthermore, if there are any portions of the furnace walls 12, 14 where the width is narrower than the width of the extruder 18 due to the convex portions, it is preferable to create a repair plan that prioritizes sandblasting the convex portions of the furnace walls 12, 14 until the width between the furnace walls 12, 14 is equal to or greater than the width of the extruder 18. If the width of the furnace walls 12, 14 becomes narrower than the width of the extruder 18, the extrusion force of the extruder 18 increases rapidly. Therefore, in such cases, it is preferable to prioritize sandblasting the convex portions of the furnace walls 12, 14 until the width of the furnace walls 12, 14 is equal to or greater than the width of the extruder 18. The width of the extruder 18 is an example of a predetermined furnace width. The predetermined furnace width may be the width of the extruder 18 multiplied by a predetermined safety factor, or may be a width determined based on other factors.

[0023] When the repair plan is created, the furnace wall profile is corrected in accordance with the repair plan (step S103). This process is the correction step. For example, if the repair plan calls for filling up half of the recessed portion, the depth of the recessed portion in the furnace wall profile is corrected to half in the correction step.

[0024] After the oven wall profile is corrected, the pushing force of the coke cake 16 is estimated using the corrected oven wall profile (step S104). This process is the pushing force estimation step. Fig. 4 is a diagram showing an example of the configuration of the pushing force estimation device 20. The pushing force estimation in step S104 may be performed using the pushing force estimation device 20 shown in Fig. 4.

[0025] The pushing force estimation device 20 is realized using, for example, a general-purpose computer such as a workstation or a personal computer, and performs a pushing force estimation process to estimate the pushing force of the coke cake 16. The pushing force estimation device 20 has, as main functional units, an input unit 22, a display unit 24, a storage unit 26, and a processing unit 28.

[0026] The input unit 22 is realized by input devices such as a keyboard, mouse, touch panel, and various switches, and outputs input signals corresponding to operational inputs to the processing unit 28. The display unit 24 is realized by a display device such as an LCD, EL display, or CRT display, and displays various screens based on display signals input from the processing unit 28.

[0027] The storage unit 26 is realized by an updatable flash memory, a built-in hard disk or a hard disk connected via a data communication terminal, an information recording medium such as a memory card, and a read / write device for the same, and a recording device suitable for the purpose can be appropriately adopted and used. In the storage unit 26, programs for operating the pushing force estimation device 20 and realizing the various functions of the pushing force estimation device 20, data used during the execution of the programs, etc. are pre-recorded or temporarily recorded each time processing is performed.

[0028] The processing unit 28 is realized by a CPU or the like, and controls the operation of the extrusion force estimation device 20 by issuing instructions to each component of the extrusion force estimation device 20 and transferring data based on input signals input from the input unit 22 and programs, data, etc. stored in the storage unit 26. By executing the programs stored in the storage unit 26, the processing unit 28 functions as an oven wall profile acquisition unit 30, a coke shape estimation unit 32, and an extrusion force estimation unit 34.

[0029] First, the principle of the pushing force estimation process executed by the pushing force estimation device 20 will be described. The pushing force estimation device 20 estimates the pushing force of the coke cake 16 using earth pressure theory, which determines the earth pressure acting on the surface where a retaining wall or the like comes into contact with the soil. Specifically, the oven walls 12, 14 of the coke oven 10 are considered to be retaining walls, and the coke cake 16 inside the inner wall surface of the coke oven wall, where deformation such as unevenness may occur, is considered to be soil. The direct pushing force of the coke cake 16 is estimated by estimating the generation states of active earth pressure and passive earth pressure in earth pressure theory based on the oven wall profile. The earth pressure, which is exerted when the retaining wall separates from the soil and whose principal stress direction is vertical, is called active earth pressure. The earth pressure, which is exerted when the retaining wall pushes the soil and whose principal stress direction is horizontal, is called passive earth pressure. Between active earth pressure and passive earth pressure, passive earth pressure has a greater normal force than active earth pressure.

[0030] In the pushing force estimation device 20, the coke cake 16 produced by carbonization inside the oven walls 12, 14 is treated as a single elastic or plastic body, and a side position where the inner wall surfaces of the oven walls 12, 14 facing both sides thereof expand outward and move away from the coke cake 16 is defined as a proactive state. In contrast, a side position where the inner wall surfaces of the oven walls 12, 14 facing both sides thereof narrow inward and move closer to the coke cake 16 is defined as a passive state.

[0031] First, as long as the oven walls 12, 14 are not deformed due to aging and the inner wall surfaces maintain the tapered shape shown in Fig. 1, the width of the coke cake 16 is always narrower than the oven width while the coke cake 16 is being extruded in the extrusion direction A1. Therefore, the coke cake 16 is extruded in a state where it is not in contact with the oven walls 12, 14 at any side position, i.e., in a active state where active earth pressure is generated.

[0032] In contrast, when unevenness is formed on the oven walls 12, 14, the outer shape of the coke cake 16 produced in the coke chamber 10 will generally conform to the inner wall surfaces of the oven walls 12, 14. That is, both side surfaces of the coke cake 16 will have a concave shape along the convex portions formed on the inner wall surfaces of the oven walls 12, 14, and will have a convex shape along the concave portions formed on the inner wall surfaces of the oven walls 12, 14.

[0033] In the process of pushing out the coke cake 16 having such an outer shape in the pushing direction A1, the width of the coke cake 16 passing through the position of the oven wall where the convex portion is formed may be wider than the oven width at this position. In such a case, the coke cake 16 is compressed by the narrow oven width and pushed out in a state where passive earth pressure is generated. Since the normal force of the passive earth pressure is greater than the active earth pressure, the pushing force required to push out the coke cake 16 increases.

[0034] Whether the coke cake 16 is in a driven state or a passive state depends on whether the width of the coke cake 16 is narrower or wider than the oven width at the passing position. Therefore, the coke cake 16 passing through a position where a convex portion is formed on the oven wall is not necessarily in a passive state. The width of the coke cake 16 is narrow at the MS and wide at the CS. Therefore, when the narrow coke width portion of the coke cake 16 at the MS passes through the oven wall position where a convex portion is formed, the coke width is narrower than the oven width and therefore the coke cake 16 is not in a passive state.

[0035] Therefore, in estimating the pushing force, the position in the pushing direction A1 of the coke cake 16 pushed by the pusher 18 in the coke chamber 10 is virtually reproduced. Then, for each virtually reproduced position, the width of the coke cake 16 is compared with the furnace width at the passage position, and the pushing force is estimated after defining a proactive state or a passive state. By repeatedly performing this operation while moving the position of the coke cake 16 from MS to CS by a predetermined amount, the pushing force at the corresponding position in the pushing direction can be sequentially estimated.

[0036] In this way, when estimating the pushing force of the coke cake 16, first, the oven wall profile acquisition unit 30 of the pushing force estimation device 20 acquires the oven wall profile corrected in step S103. The oven wall profile acquisition unit 30 outputs the acquired oven wall profile to the coke shape estimation unit 32.

[0037] The coke shape estimation unit 32 estimates the outer shape of the coke cake 16 produced in the coke chamber 10. The coke shape estimation unit 32 identifies the outer shapes of both side surfaces of the coke cake 16 after the oven walls have been repaired along the inner wall surfaces of the oven walls 12, 14 after the repair, which are indicated by the oven wall profile, and creates outer shape data of the coke cake 16. The coke shape estimation unit 32 divides the created outer shape data into a predetermined number of sections to set a calculation grid. The coke shape estimation unit 32 outputs the outer shape data of the coke cake 16 for which the calculation grid has been set and the oven wall profile to the pushing force estimation unit 34.

[0038] The pushing force estimation unit 34 uses the furnace wall profile of the carbonization chamber 10 and the external shape data of the coke cake 16 with a set calculation grid to move the position of the pusher 18 from MS to CS by a predetermined amount, and sequentially estimates the pushing force at the corresponding position in the pushing direction.

[0039] The pushing force estimating unit 34 first sets the position of the pusher 18 to the initial position (the end of the MS of the coking chamber 10). Next, the pushing force estimating unit 34 determines the relative size of the width of the coke cake 16 and the oven width for each calculation grid according to the position of the coke cake 16, using the oven wall profile of the oven walls 12, 14 and the outer shape data of the coke cake 16 for which the calculation grid is set. The pushing force estimating unit 34 defines a driving earth pressure together with the difference between the width of the coke cake 16 for a calculation grid in which the width of the coke cake 16 is narrower than the oven width, and defines a passive earth pressure together with the difference between the width of the coke cake 16 for a calculation grid in which the width of the coke cake 16 is wider than the oven width. This process is performed for all calculation grids.

[0040] The pushing force estimation unit 34 then calculates the furnace wall friction force for each computational grid and estimates the sum of these as the pushing force. The pushing force estimation unit 34 processes all computational grids in order and calculates the furnace wall friction force for each computational grid according to the definition of the active or passive state for the computational grid being processed. The apparent Young's modulus (elastic modulus) used to calculate this furnace wall friction force is statistically determined in advance based on the measured values ​​of the pushing force measured when actually pushing out the coke cake 16 produced in the coke oven and the furnace wall profile. Then, based on the definition and difference between the active and passive states of the computational grid being processed, the apparent Young's modulus is used to determine the normal force and stress that stretch or compress the computational grid being processed when passing between the opposing oven widths, and this is multiplied by the friction coefficient to calculate the furnace wall friction force. This allows the furnace wall friction force for each computational grid to be obtained.

[0041] Next, the hearth friction force is also processed for each computational grid in turn, and the hearth friction force for all computational grids is calculated. The hearth friction coefficient used to calculate this hearth friction force is a fixed value that is set in advance. Since the volume of the computational grid is calculated, the weight is calculated from the coke density calculated in advance, and the hearth friction force is calculated by multiplying the calculated weight by the hearth friction force. In this way, the hearth friction force for all computational grids is obtained.

[0042] Then, by adding up the sum of the furnace wall friction forces for each calculation grid and the sum of the hearth friction forces for each calculation grid, the pushing force required to push the coke cake 16 at the current position can be estimated. After estimating the pushing force as described above, the pushing force estimation unit 34 updates the pusher position by moving it a predetermined amount toward the CS, and repeatedly executes the above-described process until the position of the coke cake 16 reaches the end position of the CS of the coke chamber 10. In this way, the pushing force estimation unit 34 estimates the pushing force of the coke cake 16 in the coke chamber 10.

[0043] Fig. 5 is a graph showing an example of the pushing force of the coke cake 16 estimated by the pushing force estimation device 20. The horizontal axis of Fig. 5 represents the position (m) of the extruder 18, and the vertical axis represents the pushing force (kN). As shown in Fig. 5, the pushing force of the coke cake was observed to be maximum near MS, and then gradually decreased as it approached CS.

[0044] Referring again to FIG. 3, in step S105, the time required to execute the repair plan created in step S102 is calculated. This process is the repair time calculation step. In furnace wall repair, recesses are filled by thermal spraying, and protrusions are cut by sandblasting. ３ Filling processing time per 1m ３ The cutting processing time per unit volume can be determined from past work results, so the time required to execute the repair plan can be calculated from the processing time per unit volume, the padding volume and cutting volume in the furnace wall repair plan.

[0045] The pushing force after the oven wall repair is estimated, the oven wall repair time is calculated, and then the oven wall repair is carried out (step S106). This process is the repair step. As described above, in the coke oven wall repair method according to this embodiment, before carrying out the coke oven wall repair, the time required for the oven wall repair is calculated, and the pushing force of the coke cake 16 after the oven wall repair is estimated. As a result, in the coke oven wall repair method according to this embodiment, the oven wall repair can be carried out while taking into account the pushing force after the oven wall repair and the time required for the oven wall repair. As a result, the time required for the oven wall repair of the coke oven chamber 10 is reduced, and the oven wall repair can be carried out by achieving a good balance between the pushing force after the oven wall repair and the time required for the oven wall repair.

[0046] The above describes the method for repairing a coke oven wall according to the present embodiment. However, the present invention is not limited to the above embodiment and various modifications can be made. In the above embodiment, an example was shown in which the pushing force of the coke oven 10 after repair was estimated using the corrected oven wall profile in estimating the pushing force in step S104. However, in addition to this, the pushing force may also be estimated using the oven wall profile before correction. The oven wall profile before correction is an oven wall profile that reflects the oven wall condition of the coke oven chamber 10 before the oven wall repair. By estimating the pushing force using the oven wall profile before correction, the pushing force of the coke cake 16 in the coke oven chamber 10 before the oven wall repair can be estimated. Therefore, it is possible to determine the need for oven wall repair of the coke oven chamber 10 and then carry out the oven wall repair.

[0047] Fig. 6 is a flow diagram illustrating another embodiment of the coke oven wall repair method according to the present embodiment. The flow shown in Fig. 6 differs from the flow shown in Fig. 3 in that it includes step S201 for determining whether the estimated pushing force is equal to or less than a predetermined target value, and step S202 for determining whether the calculated repair time is equal to or less than the target time. In Fig. 6, the same steps as in Fig. 3 are assigned the same step numbers, and their descriptions will be omitted.

[0048] In the flow shown in FIG. 6 , after the pushing force is estimated in step S104, it is determined whether the estimated pushing force is equal to or less than a predetermined pushing force target value (step S201). If the pushing force estimated in step S104 is equal to or less than the predetermined pushing force target value (step S201: Yes), the process proceeds to step S105. On the other hand, if the pushing force estimated in step S104 is greater than the predetermined target value (step S201: No), the process returns to step S102, and steps S102 to S104 may be repeated until a furnace wall repair plan is created in which the estimated pushing force is equal to or less than the predetermined target value. This prevents the pushing force of the coke cake 16 from exceeding the target value.

[0049] Furthermore, after the repair time is calculated in step S105, it is determined whether the calculated repair time is equal to or shorter than the target time (step S202). If the repair time calculated in step S105 is equal to or shorter than the predetermined target time (step S201: Yes), the process proceeds to step S106. On the other hand, if the repair time calculated in step S105 is longer than the target time (step S201: No), the process returns to step S102, and the processes from step S102 to step S104, step S201, and step S105 may be repeated until a furnace wall repair plan is created in which the calculated repair time is equal to or shorter than the target time. This prevents the repair time from being longer than the predetermined target time, thereby avoiding the furnace wall repair from taking a long time.

[0050] Next, an example will be described in which a repair plan was created for a coke chamber that had deteriorated and become clogged, the coke cake pushing force was estimated, and the repair time was calculated. Fig. 7 is a diagram showing an oven wall profile before oven wall repair and an estimated value of the pushing force of the coke cake 16. Fig. 7(a) is an oven wall profile on one side before oven wall repair. Fig. 7(b) is a graph showing an estimated value of the pushing force of the coke cake 16 before oven wall repair, estimated using Fig. 7(a).

[0051] As shown in Fig. 7(a), there were protrusions (convex portions) and depressions (concave portions) before the oven wall was repaired. Therefore, as shown in Fig. 7(b), it was estimated that the pushing force of the coke cake 16 in this coke chamber would be 485 kN, which exceeded the target pushing force of 450 kN, and there was concern that the coke cake would stop pushing or clog.

[0052] Fig. 8 is a diagram showing an oven wall profile corrected in accordance with an oven wall repair plan and an estimated value of the pushing force of the coke cake 16. Fig. 8 shows an example in which an oven wall repair plan has been created to flatten gouges in the oven wall by thermal spraying. Fig. 8(a) is an oven wall profile on one side corrected in accordance with the oven wall repair plan. Fig. 8(b) is a graph showing an estimated value of the pushing force of the coke cake 16 after the oven wall repair, estimated using Fig. 8(a).

[0053] As shown in Figure 8(a), in the corrected oven wall profile, the gouges that existed in Figure 7(a) have been flattened by thermal spraying. As a result of the gouges being flattened, it was estimated that the pushing force of the coke cake 16 would decrease from 485 kN to 426 kN, which is below the target value of 450 kN, as shown in Figure 8(b). The oven wall repair time was calculated based on the gouge volume of 0.4 m3 calculated from the oven wall profile. ３ The spraying rate was 80 kg / h, and the spray density was 1700 kg / m ３ The furnace wall repair time for repairing the gouges was calculated to be 10 hours.

[0054] Furnace wall repair time (h) = (volume of gouges × spraying density × 100) / (spraying rate × spraying yield) (1)

[0055] Fig. 9 is a diagram showing an oven wall profile corrected in accordance with an oven wall repair plan and an estimated value of the pushing force of the coke cake 16. Fig. 9 shows an example in which an oven wall repair plan is created in which the oven wall overhang is flattened by cutting using sandblasting. Fig. 9(a) is an oven wall profile on one side corrected by the oven wall repair plan. Fig. 9(b) is a graph showing an estimated value of the pushing force of the coke cake 16 after the oven wall has been repaired, estimated using Fig. 9(a).

[0056] As shown in Fig. 9(a), in the corrected oven wall profile, the overhang that existed in Fig. 7(a) has been flattened by cutting with sandblasting. As a result of the overhang being flattened, it was estimated that the pushing force of the coke cake 16 would be reduced from 485 kN to 390 kN, which is less than the target value of 450 kN, as shown in Fig. 9(b). The oven wall repair time was calculated based on the overhang volume of 0.6 m3 calculated from the oven wall profile. ３ Cutting speed 0.016 m ３ The furnace wall repair time for repairing the overhang was calculated to be 38 hours.

[0057] Fig. 10 is a diagram showing an oven wall profile corrected by an oven wall repair plan and an estimated value of the pushing force of the coke cake 16. Fig. 10 shows an example in which an oven wall repair plan is created in which gouges on the oven wall are smoothed by thermal spraying and overhangs are smoothed by cutting using sandblasting. Fig. 10(a) is an oven wall profile on one side corrected by the oven wall repair plan. Fig. 10(b) is a graph showing an estimated value of the pushing force of the coke cake 16 after oven wall repair, estimated using Fig. 10(a).

[0058] As shown in Fig. 10(a), in the corrected oven wall profile, the gouges that were present in Fig. 7(a) have been smoothed by thermal spraying, and the overhangs have been smoothed by cutting. As a result of smoothing the gouges and overhangs, it is estimated that the pushing force of the coke cake 16 will be reduced from 485 kN to 379 kN, which is below the target value of 450 kN, in Fig. 10(b). Because the thermal spraying and cutting operations cannot be performed in parallel, the oven wall repair time is calculated by adding the oven wall repair time by thermal spraying to the oven wall repair time by cutting. The oven wall repair time for repairing the gouges and overhangs was calculated to be 48 hours.

[0059] 8 to 10, it can be seen that, for example, if it is desired to reduce the pushing force to a target value of 450 kN or less in a short time, it is sufficient to adopt an oven wall repair plan in which the gouges on the oven wall are smoothed by thermal spraying. Note that, since the pushing force of the coke cake 16 is reduced to 426 kN simply by smoothing the gouges as shown in Fig. 8(b), the area of ​​the gouges to be smoothed by thermal spraying may be reduced to further shorten the repair time.

[0060] As described above, in the coke oven wall repair method according to this embodiment, a repair plan for the oven wall is created based on the oven wall profile of the coke oven chamber, the pushing force of the coke cake after the oven wall has been repaired according to the repair plan is estimated, and the time required to execute the created repair plan is calculated. This allows the oven wall repair to be carried out while taking into consideration the pushing force after the oven wall repair and the time required for the oven wall repair, so that the oven wall repair can be carried out while achieving a good balance between the time required for the oven wall repair and the pushing force of the coke cake after the oven wall repair in accordance with the status of the coke oven.

[0061] REFERENCE SIGNS LIST 10 carbonization chamber 12 furnace wall 14 furnace wall 16 coke cake 18 extruder 20 extrusion force estimating device 22 input unit 24 display unit 26 storage unit 28 processing unit 30 furnace wall profile acquisition unit 32 coke shape estimating unit 34 extrusion force estimating unit

Claims

1. A method for repairing a coke oven wall of a carbonization chamber constituting a coke oven, comprising the steps of: An acquisition step of acquiring a furnace wall profile by measuring the unevenness of the furnace wall; A repair plan creation step of creating a repair plan for repairing the unevenness; modifying the furnace wall profile in accordance with the repair plan; A pushing force estimating step of estimating a pushing force for pushing the coke cake in the carbonization chamber by an extruder using the corrected furnace wall profile; A repair time calculation step of calculating a time required to execute the repair plan; A repair step of repairing the furnace wall according to the repair plan; The method for repairing a coke oven wall comprises:

2. The method for repairing a coke oven wall according to claim 1 , wherein in the obtaining step, the pushing force is estimated using the obtained oven wall profile.

3. 3. The method for repairing a coke oven wall according to claim 1, wherein in the obtaining step, the oven wall profile is obtained by irradiating the oven wall with laser light from a laser type three-dimensional shape measuring device.

4. The method for repairing a coke oven wall according to claim 3, wherein the oven wall profile is obtained by irradiating a laser beam onto each of the left and right oven walls of the coke oven chamber.

5. 3. A coke oven wall repair method as described in claim 1 or claim 2, wherein in the repair plan creation step, a repair plan for repair work that results in a large reduction in pushing force per repair work hour is created preferentially from among a repair plan for cutting a convex portion of the oven wall and a repair plan for filling a concave portion of the oven wall.

6. 3. A coke oven wall repair method as described in claim 1 or claim 2, wherein, when there is a portion where the oven width is narrower than a predetermined width due to a convex portion of the oven wall, in the repair plan creation step, a repair plan is created to cut the convex portion of the oven wall until the oven width is equal to or greater than the predetermined width before creating a repair plan to fill in the concave portion of the oven wall.

7. 3. A coke oven wall repair method as described in claim 1 or claim 2, wherein in the pushing force estimation step, it is further determined whether the estimated pushing force is equal to or less than a target value of the pusher, and if the estimated pushing force is greater than the target value, the repair plan is changed.

8. 3. A coke oven wall repair method as described in claim 1 or claim 2, wherein the repair time calculation step further comprises determining whether the calculated time is within a predetermined target time, and changing the repair plan if the calculated time is longer than the target time.