Coke oven abnormality detection method

Abstract

To provide an abnormality detection method for a coke oven capable of detecting abnormalities within the coke oven with high accuracy.SOLUTION: An abnormality detection method for a coke oven comprises: an extrusion step; a measurement step; and a determination step. In the extrusion step, a ram beam 11 is moved in a furnace length direction, and a ram head 12 pushes out coke 20 from a carbonization chamber 80. In the measurement process, when a position of the ram head 12 in the furnace length direction is defined as x, extrusion load F(x) of an engine at a position x is measured during the extrusion step. In the determination step, if the extrusion load F(x) measured in the measurement step satisfies F(x)<F(a) within a range of a≤x≤100, it is determined that an abnormality has occurred in the coke oven. (The position of the ram head just before the ram head starts contacting the coke is x=0, the position of the ram head just before a slide shoe enters the carbonization chamber is x=a, and the position of the ram head at a time when extrusion of the coke from the carbonization chamber is completed is x=100.)SELECTED DRAWING: Figure 10

Description

[Technical Field]

[0001] The present disclosure relates to a method for detecting an abnormality in a coke oven. [Background technology]

[0002] Coke used in steelmaking is produced by charging raw coal into a coke oven and carbonizing the coal at high temperatures. The coke oven is, for example, a chamber-type coke oven. A coke oven has a structure in which carbonization chambers, which convert coal into coke, and combustion chambers, which supply heat to the carbonization chamber, are arranged alternately in parallel, and the carbonization chambers and combustion chambers are separated by a furnace wall made of bricks. Fuel gas burns inside the combustion chamber, and heat from the combustion chamber is supplied to the carbonization chamber through thermal conduction through the furnace wall. Room-temperature coal is charged into the carbonization chamber. The heat from the combustion chamber promotes carbonization of the coal in the carbonization chamber, and the coal is carbonized to form coke. A kiln port is provided at each end of the carbonization chamber. The coke in the carbonization chamber is pushed out of the carbonization chamber by an extruder. Specifically, the coke in the carbonization chamber is pushed from one port of the carbonization chamber to the other by the extruder, and is discharged outside the furnace. The discharged coke is guided by a guide car to a fire extinguishing car, which then transports it. Hereinafter, one of the kiln openings of the carbonization chamber will be referred to as the "extruder-side kiln opening," and the other will be referred to as the "guide car-side kiln opening."

[0003] The extruder includes, for example, a ram beam extending from the extruder-side kiln opening along the guide car-side kiln opening, a ram head fixed to the tip of the ram beam, and a slide shoe disposed below the ram beam and integrated with the ram beam. During coke extrusion, the ram head comes into contact with the coke, and the slide shoe supports the ram beam while sliding on the hearth.

[0004] The coke chamber and the combustion chamber each extend in a direction from the extruder-side kiln port toward the guide car-side kiln port. Hereinafter, the direction in which the coke chamber and the combustion chamber extend is also referred to as the "furnace length direction." The dimensions of the coke chamber and the combustion chamber in the furnace length direction are, for example, several tens of meters. Hereinafter, during coke extrusion, frictional forces are generated between the coke and the furnace wall, and between the coke and the furnace bottom. Hereinafter, the furnace wall and the furnace bottom are also collectively referred to as the "furnace surface." In particular, if the coke is not sufficiently carbonized or if the bricks on the furnace wall are uneven, excessive frictional resistance occurs to the coke. In such cases, the extrusion properties of the coke deteriorate.

[0005] If the coke extrusion property deteriorates excessively, the oven wall may be damaged or may collapse on a large scale, and in some cases, coke jamming may occur. Coke jamming refers to a situation in which the reaction force acting on the extruder during the extrusion of coke into the coke chamber suddenly increases, making it impossible for the extruder to push the coke out, resulting in the coke being stuck in the coke chamber. If coke jamming occurs, the coke oven must be stopped, the coke must be manually removed from the coke chamber, and the oven wall must then be repaired. Therefore, when coke jamming occurs, coke productivity decreases and repair costs increase.

[0006] As coke ovens age, problems with the oven body become more pronounced. Therefore, there is a need to establish technology that allows stable operation even when aging coke ovens are used. To stabilize coke oven operation, it is necessary to detect deterioration in extrudability early during coke extrusion.

[0007] Patent Document 1, for example, is known as a technology for detecting deterioration in pushability. In the technology described in Patent Document 1, when coke is pushed by a push ram driven by a motor, an ideal load current trend is calculated in advance, taking into account the operating state of the coke oven, from the load current trend measured by measuring the load current of the motor relative to the push position of the push ram in the coke chamber. Then, the deviation of the load current for each push position between the actual load current trend after completion of coke push in the coke chamber to be measured and the above-mentioned ideal load current trend is calculated. Patent Document 1 states that an abnormality in the coke chamber is determined from the deviation calculated in this way. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-171791 Summary of the Invention [Problem to be solved by the invention]

[0009] In the anomaly detection method of Patent Document 1, the ideal load current trend is determined by multiplying the average value of 5 to 10 load current trends by various correction coefficients. Therefore, if the measurement conditions change significantly, such as when the inside of the coking chamber is repaired, the accuracy of anomaly detection will decrease.

[0010] An object of the present disclosure is to provide a method for detecting an abnormality in a coke oven that can detect an abnormality in the coke oven with high accuracy. [Means for solving the problem]

[0011] The abnormality detection method according to the present disclosure is a coke oven abnormality detection method that detects an abnormality when pushing coke in the coke oven chamber out of the coke oven chamber using a pusher. The pusher includes a ram beam, a ram head, a slide shoe, and an engine that applies force to move the ram beam in the oven length direction. The ram beam extends in the oven length direction. The ram head is fixed to the tip of the ram beam. The slide shoe is disposed below the ram beam and is integrated with the ram beam. The abnormality detection method according to the present disclosure includes a pushing step, a measuring step, and a determining step. In the pushing step, the ram beam is moved in the oven length direction, and the ram head pushes the coke out of the coke oven chamber. In the measuring step, when the position of the ram head in the oven length direction is x, the pushing load F(x) of the engine at position x is measured during the pushing step. In the determining step, it is determined that an abnormality has occurred in the coke oven if the pushing load F(x) measured in the measuring step satisfies the following formula (1) within the range of a≦x≦100:

number

[0012] Another anomaly detection method according to the present disclosure is a coke oven anomaly detection method that uses the pusher to detect an anomaly when pushing coke in the coke oven chamber out of the coke oven chamber. The anomaly detection method according to the present disclosure includes a pushing step, a measurement step, and a determination step. In the pushing step, the ram beam is moved in the oven length direction, and the ram head pushes the coke out of the coke oven chamber. In the measurement step, when the position of the ram head in the oven length direction is defined as x, the engine pushing load F(x) at position x during the pushing step is measured. In the determination step, it is determined that an anomaly has occurred in the coke oven if the pushing load F(x) measured in the measurement step satisfies the following formula (4) within the range of a≦x≦100:

number

[0013] According to the coke oven abnormality detection method of the present disclosure, abnormalities in a coke oven can be detected with high accuracy. [Brief explanation of the drawings]

[0014] [Figure 1] FIG. 1 is a diagram showing an example of an extrusion waveform of a coke oven. [Figure 2] FIG. 2 is a diagram showing an example of an extrusion waveform of a coke oven. [Figure 3] FIG. 3 is a diagram showing an example of an extrusion waveform of a coke oven. [Figure 4] FIG. 4 is a diagram showing an example of an extrusion waveform of a coke oven. [Figure 5] FIG. 5 is a schematic diagram showing the overall configuration of a coke oven. [Figure 6] FIG. 6 is a cross-sectional view taken along line VI-VI in FIG. [Figure 7] FIG. 7 is a side view of the extruder. [Figure 8] FIG. 8 is a flow chart showing a method for detecting an abnormality in a coke oven according to the embodiment. [Figure 9] FIG. 9 is a schematic diagram showing the extrusion process. [Figure 10] FIG. 10 is a schematic diagram showing the extrusion process. [Figure 11] FIG. 11 is a schematic diagram showing the extrusion process. [Figure 12] FIG. 12 is a diagram showing an example of an extrusion waveform of a coke oven. [Figure 13] FIG. 13 is a diagram showing an example of an extrusion waveform of a coke oven. [Figure 14] FIG. 14 is a diagram showing an extrusion waveform according to the first embodiment. [Figure 15] FIG. 15 is a diagram showing the transition of the pile height of the coke lumps depending on the position of the ram head. [Figure 16] FIG. 16 is a diagram showing the relationship between the pile height of the coke lumps and the pushing load. DETAILED DESCRIPTION OF THE INVENTION

[0015] To solve the technical problem of detecting deterioration in extrusion performance in a coke oven at an early stage, the inventors focused on the reaction force acting on the extruder during coke extrusion. The reaction force acting on the extruder corresponds to the torque of the motor that drives the extruder, and is hereinafter also referred to as the "extrusion load." Specifically, the inventors discovered that signs of abnormalities (such as packing) in the furnace during coke extrusion can be recognized from the transition of the extrusion load (hereinafter also referred to as the "extrusion waveform") detected in response to the amount of movement of the ram head of the extruder.

[0016] FIG. 1 is a diagram showing an example of a coke oven extrusion waveform. FIG. 1 shows the extrusion waveform when the inside of the oven is in a healthy state. A healthy oven state refers to a state in which no abnormalities such as coke packing occur and coke is smoothly extruded. The extrusion waveform shown in FIG. 1 is an extrusion waveform when, for example, a newly installed coke oven is used.

[0017] In Figure 1, the horizontal axis shows the position of the ram head relative to the extruder-side kiln port, i.e., the amount of movement of the ram head from the extruder-side kiln port of the coking chamber. In Figure 1, the amount of movement of the ram head is shown as an actual measured value from the extruder-side kiln port. This is also true for Figures 2 to 4, which will be described later.

[0018] In Figure 1, the vertical axis represents the extrusion load. The extrusion load is shown as a relative value when the upper limit of the extrusion load, which is set from the viewpoint of preventing damage to extruder equipment and protecting the furnace body, is set to 1.0. In other words, the extrusion load is shown as a relative value to the upper limit of the extrusion load. This is the same in each figure described later.

[0019] After carbonization, the coke in the carbonization chamber is pushed from one end of the chamber to the other by an extruder. When the extruder begins to push the coke, it is crushed by the extruder's ram head and compressed as a whole. At this time, static friction acts between the coke and the furnace surface, and the coke remains stationary. As the pushing load increases, the friction between the coke and the furnace surface reaches its maximum value (maximum static friction force), and the coke begins to move. Once the coke begins to move, it is subjected to a kinetic friction force that is smaller than the maximum static friction force. Therefore, the pushing load drops sharply after reaching its maximum value.

[0020] In the following, the period from when the pushing load begins to rise sharply to when the pushing load reaches its maximum value and then its rapid drop is completed, i.e., the portion corresponding to the peak of the pushing waveform, is referred to as the "peak" of the pushing load. The peak that first appears after coke pushing begins is referred to as the "initial peak" of the pushing load. In the example of the pushing waveform shown in Figure 1, the initial peak appears between 0 and 0.9 m of ram head movement. The value of the pushing load when it reaches its maximum value is referred to as the "peak value." The peak value of the initial peak corresponds to the maximum static friction force between the coke and the furnace surface. In the example of the pushing waveform shown in Figure 1, the pushing load reaches its maximum value when the ram head moves approximately 0.6 m, and the peak value is 0.15.

[0021] Usually, when coke is extruded, the coke starts moving before the slide shoe of the extruder enters the coke chamber. It can be said that the compression of the coke is completed before the slide shoe enters the coke chamber. Therefore, when the slide shoe of the extruder enters the coke chamber, the initial peak of the extrusion load has passed.

[0022] On the other hand, once the coke begins to move, as the ram head's movement increases, the coke is discharged from the guide car side of the coke chamber opening. Then, the amount of coke in the coke chamber gradually decreases, and the load required for the ram head to push the coke decreases. In other words, the pushing load gradually decreases. Therefore, in a healthy furnace, as is clear from the pushing waveform shown in Figure 1, the pushing load after the initial peak actually decreases as the ram head's movement increases. In a healthy furnace, the pushing load after the slide shoe enters the coke chamber also gradually decreases as the ram head's movement increases.

[0023] Here, in newly constructed coke ovens, the peak value at the initial peak is very small. On the other hand, in aged coke ovens, the peak value at the initial peak is large. This is thought to be because as the coke oven ages, the furnace surface of the coke chamber wears out, increasing the frictional force acting between the coke and the furnace surface, and making it more likely that poor coke carbonization will occur due to poor combustion and deterioration of heat transfer.

[0024] FIG. 2 shows an example of a coke oven extrusion waveform. FIG. 2 shows an extrusion waveform when the coke oven has deteriorated and a portion of the oven wall has bulged or protruded. In the extrusion waveform shown in FIG. 2, the peak value at the initial peak is larger than the peak value at the initial peak of the extrusion waveform shown in FIG. 1. Furthermore, the extrusion load after the initial peak remains high for a while, even when the ram head travel distance increases, in the range of approximately 2.0 to 6.5 m. This is thought to be because the kinetic frictional force acting between the coke and the oven surface is larger in an aging coke oven than in a coke oven with a healthy interior.

[0025] However, the coke chamber generally has a horizontal taper. In other words, the width of the coke chamber increases from the extruder-side kiln opening to the guide car-side kiln opening. This horizontal taper of the coke chamber increases the clearance between the coke and the oven wall as the ram head travels more during coke extrusion. Therefore, even if the coke oven deteriorates somewhat and the oven wall bulges or protrudes, as long as the coke is sufficiently durable and has undergone sufficient wear, the ram head travel will continue to progress to a certain extent after the initial peak, as shown in Figure 2. After the ram head travels approximately 6.5 m, the extrusion load gradually decreases as the ram head travel increases.

[0026] The above describes the extrusion waveform when no abnormality occurs in the coke oven with reference to Figures 1 and 2. The present inventors have conducted extensive research focusing on the extrusion waveform when an abnormality occurs in the coke oven. As a result, the present inventors have found that when an abnormality occurs in the coke oven, not only does the peak value at the initial peak (the maximum static friction force between the coke and the oven surface) become significantly large, but also, as shown in the extrusion waveforms in Figures 3 and 4 (described later), the extrusion load peaks during the actual extrusion period or a significant waveform change occurs after the initial peak. The actual extrusion period refers to the period from the start of coke extrusion to the completion of extrusion, during which the coke is being discharged from the coke chamber after the initial peak of the extrusion load.

[0027] Figure 3 shows an example of a coke oven push waveform. Figure 3 shows a push waveform when an abnormality occurs in the coke oven. When an abnormality occurs in the coke oven, as shown in Figure 3, the push load may suddenly increase during the actual push period. Specifically, after the initial peak, when the ram head has moved to a certain extent and the push load is decreasing, the push load temporarily increases and becomes much higher than the push load immediately before the slide shoe enters the coke chamber. The main causes of the temporary increase in the push load are local wear and damage to the oven wall and hearth bricks, and the degree of carbonization of the coke. In addition to these causes, the following three other possible causes are considered. First, at the end of the actual push period, the coke near the ram head collapses, which causes the force applied by the ram head to the coke to be dispersed in the oven length direction and the width direction of the coke chamber, which is perpendicular to the oven length direction. This requires a larger load to push the coke, increasing the push load. The second cause is that the collapsed coke creates frictional resistance between the coke cake and the oven wall, and this frictional resistance is applied to the ram head. The third cause is that if the coke cake is weak, an upward shear force acts on the coke cake as it slides against the oven bottom, causing it to rise. When the coke cake rises, it comes into contact with the ceiling of the coke chamber or narrow (curved) parts of the oven wall, generating frictional forces at the contact points between the coke cake and the coke chamber. If an abnormality occurs in the coke oven due to these causes, an abnormal extrusion waveform may occur.

[0028] FIG. 4 shows an example of a coke oven extrusion waveform. FIG. 4 shows an extrusion waveform when an abnormality occurs in the coke oven. When an abnormality occurs in the coke oven, the extrusion load may rise again immediately after the initial peak without decreasing. In the example shown in FIG. 4, the extrusion load increases when the ram head travels approximately 4.0 to 9.5 m. The inventors have found that with such an extrusion waveform, coke jamming occurs with a high probability. Furthermore, the inventors have newly discovered that the cause of the abnormal extrusion waveform shown in FIG. 4 is coke lumps that spill out between the extruder ram head and the oven wall during coke extrusion and remain in the oven.

[0029] When coke lumps spill into the furnace, they accumulate on the hearth in front of the slide shoe of the extruder. In other words, the coke lumps accumulate between the ram head and the slide shoe. This generates friction between the slide shoe, which slides against the hearth, and the coke lumps, increasing the extrusion load. In addition, mechanical load is generated when the slide shoe rides over the coke lumps accumulated on the hearth.

[0030] It is generally known that even if the next batch of coal is charged into a coke oven with coke lumps remaining in the hearth and carbonized, the remaining coke lumps will not merge with the new coke produced by carbonizing the coal. Therefore, if the coke oven continues to operate with coke lumps remaining in the hearth, the coke at the hearth will become brittle and prone to crumbling, increasing the risk of jamming. To ensure stable operation of a coke oven, it is necessary to detect early deterioration in coke extrudability caused by these factors.

[0031] The method for detecting an abnormality in a coke oven according to an embodiment of the present disclosure has been completed based on the above findings.

[0032] An anomaly detection method according to an embodiment is a coke oven anomaly detection method that uses a pusher to detect an anomaly when pushing coke in the coke oven chamber out of the coke oven chamber. The pusher includes a ram beam, a ram head, a slide shoe, and an engine that applies force to move the ram beam in the oven length direction. The ram beam extends in the oven length direction. The ram head is fixed to the tip of the ram beam. The slide shoe is disposed below the ram beam and is integrated with the ram beam. The anomaly detection method according to the present disclosure includes a pushing step, a measuring step, and a determining step. In the pushing step, the ram beam is moved in the oven length direction, and the ram head pushes the coke out of the coke oven chamber. In the measuring step, when the position of the ram head in the oven length direction is defined as x, a pushing load F(x) of the engine at position x is measured during the pushing step. In the determining step, it is determined that an anomaly has occurred in the coke oven if the pushing load F(x) measured in the measuring step satisfies the following formula (1) within the range of a≦x≦100:

number

[0033] Normally, the coke starts moving and the initial peak of the pushing load has passed before the slide shoe of the pusher enters the coke chamber. Therefore, if there is no abnormality in the coke oven, the pushing load after the slide shoe enters the coke chamber gradually decreases as the movement of the ram head increases.

[0034] The first configuration of the anomaly detection method determines that an abnormality has occurred in the coke oven if the pushing load F(x) satisfies formula (1) within the range of a≦x≦100. That is, the first configuration of the anomaly detection method determines that an abnormality has occurred in the coke oven if the pushing load F(x) after the slide shoe enters the coke chamber is greater than the pushing load F(a) immediately before the slide shoe enters the coke chamber. As shown in FIGS. 3 and 4, when an abnormality has occurred in the coke oven, the pushing load peaks during the actual pushing period or a significant waveform change occurs after the initial peak. The first configuration of the anomaly detection method determines that an abnormality has occurred when such an extrusion waveform is measured during coke extrusion. Therefore, the first configuration of the anomaly detection method can also detect coke oven abnormalities that have not been considered in the past (specifically, an abnormality caused by coke lumps spilling out from between the pusher and the oven wall during coke extrusion and remaining in the oven). Therefore, according to the anomaly detection method of the first configuration, an anomaly in a coke oven can be detected with high accuracy.

[0035] In the abnormality detection method of the first configuration, in the judgment step, the coking chamber is further divided into sections in the range of a≦x≦100, each section having a dimension in the furnace length direction of 5% of the total length of the coking chamber, and the value obtained by averaging the pushing load F(x) in the A-th section is called the pushing load average F A When the average extrusion load F A It may be determined that an abnormality has occurred in the coke oven when the following formula (2) is satisfied (second configuration).

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[0036] In the second configuration of the abnormality detection method, if the formula (2) is satisfied in addition to the formula (1), it is determined that an abnormality exists inside the coke oven. If the formula (2) is satisfied, the coke oven is divided into sections with a dimension of 5% in the oven length direction, and the pushing load F(x) in the Ath section is averaged to obtain the average pushing load F(x). AThe value of F(x) becomes larger than the pushing load F(a) immediately before the slide shoe enters the coke chamber. In other words, the abnormality detection method of the second configuration determines that an abnormality has occurred in the coke oven not only when the pushing load F(x) momentarily becomes larger than F(a) but also when the average value of the pushing load F(x) within the interval is larger than F(a). Therefore, the abnormality detection method of the second configuration can reduce the risk of false detection.

[0037] In the abnormality detection method of the second configuration, the determination step further comprises determining a value obtained by averaging the pushing load F(x) in the (A+1)th section as the pushing load average F A+1 When the average extrusion load F A and F A+1 It may be determined that an abnormality has occurred in the coke oven when the following formula (3) is satisfied (third configuration).

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[0038] In the third configuration of the abnormality detection method, if the formula (3) is satisfied in addition to the formulas (1) and (2), it is determined that an abnormality exists inside the coke oven. If the formula (3) is satisfied, the coke oven is divided into sections with a dimension of 5% in the oven length direction, and the pushing load F(x) in the Ath section is averaged to obtain the pushing load average F(x). A , and the average pushing load F(x) in the (A+1)th section A+1 However, both of these are larger than the pushing load F(a) just before the slide shoe enters the coking chamber. Furthermore, the average pushing load F within the (A+1)th section A+1 is the average extrusion load F in the Ath section A In other words, in the anomaly detection method of the third configuration, if the pushing load F(x) increases as the coke pushing progresses from the Ath section to the (A+1)th section, which are adjacent to each other, it is determined that an abnormality has occurred in the coke oven. Therefore, the anomaly detection method of the third configuration can further reduce the risk of false detection.

[0039] Another anomaly detection method according to the present embodiment is a coke oven anomaly detection method that uses the pusher to detect an anomaly when pushing coke in the coke oven chamber out of the coke oven chamber. The anomaly detection method according to the present disclosure includes a pushing step, a measurement step, and a determination step. In the pushing step, the ram beam is moved in the oven length direction, and the ram head pushes the coke out of the coke oven chamber. In the measurement step, when the position of the ram head in the oven length direction is defined as x, the engine pushing load F(x) at position x during the pushing step is measured. In the determination step, it is determined that an anomaly has occurred in the coke oven if the pushing load F(x) measured in the measurement step satisfies the following formula (4) within the range of a≦x≦100:

number

[0040] In the fourth configuration of the abnormality detection method, if the pushing load F(x) satisfies the formula (4) in the range of a≦x≦100 during the pushing process, it is determined that an abnormality has occurred in the coke oven. In other words, in the fourth configuration of the abnormality detection method, it is determined that the work done by the pusher after the slide shoe enters the coke oven chamber is less than S minWhen the difference is greater than 1.2 times the initial value, it is determined that an abnormality has occurred in the coke oven. In the extrusion waveform when an abnormality has occurred in the coke oven, as shown in Figures 3 and 4, a peak in the extrusion load appears during the actual extrusion period, or the waveform changes after the initial peak. The work done by the extruder when such an extrusion waveform is observed is much greater than the work done by the extruder when the coke oven is in a healthy state. Therefore, the abnormality detection method of the fourth configuration can determine that an abnormality has occurred when such an extrusion waveform is measured during coke extrusion. Therefore, according to the fourth configuration, an abnormality in the coke oven can be detected with high accuracy, similar to the abnormality detection method of the first configuration.

[0041] Hereinafter, a method for detecting an abnormality in a coke oven according to an embodiment of the present disclosure will be described with reference to the drawings. In the drawings, the same or corresponding parts are designated by the same reference numerals, and duplicated explanations will be omitted as appropriate.

[0042] [First embodiment] [Coke oven] The overall configuration of a coke oven will be described with reference to Figures 5 and 6. Figure 5 is a schematic diagram showing the overall configuration of a coke oven. Figure 6 is a cross-sectional view taken along line VI-VI in Figure 5. In other words, Figure 6 is a cross-sectional view perpendicular to the furnace length direction. A coke oven has a structure in which coke chambers 80 and combustion chambers 90 are alternately arranged in parallel. Coal is fed into the coke chamber 80. The combustion chamber 90 supplies heat to the coke chamber 80. The heat supplied from the combustion chamber 90 carbonizes the coal in the coke chamber 80 to form coke. The coke is pushed by the extruder 10 from the extruder-side kiln opening 81 of the coke chamber 80 toward the guide car-side kiln opening 82, and is discharged from the coke chamber 80. The discharged coke is guided to the fire extinguisher truck 70 by a guide car (not shown). The coke is then transported to the next process by the fire extinguisher truck 70.

[0043] The coking chamber 80 and the combustion chamber 90 are composed of a ceiling portion 83 and a hearth 84. Adjacent coking chambers 80 and combustion chambers 90 are separated by a furnace wall 85. These furnace walls 85 connect the ceiling portion 83 and the hearth 84, respectively. A coal loading port 86 for loading coal is provided in the ceiling portion 83 of each coking chamber 80. The coal loading port 86 penetrates the ceiling portion 83.

[0044] [Extruder] Figure 7 is a side view of the extruder 10. Referring to Figure 7, the extruder 10 includes a ram beam 11, a ram head 12, a slide shoe 13, and a motor 14. The ram beam 11 extends in the furnace length direction. A rack gear 15 is provided on the upper part of the ram beam 11. The rack gear 15 extends in the furnace length direction. The ram head 12 is fixed to the tip of the ram beam 11.

[0045] The slide shoe 13 is disposed below the ram beam 11 and is integrated with the ram beam 11. As the size of a coke oven increases, the overall length of the extruder 10 for pushing out the coke from the coke oven (the length of the ram beam 11 in the oven length direction) also increases. The slide shoe 13 is provided to prevent the ram beam 11 from bending downward. Typically, the slide shoe 13 is disposed near the tip of the ram beam 11.

[0046] A pinion gear 16 is connected to the motor 14. The pinion gear 16 rotates by the driving force of the motor 14. The pinion gear 16 is connected to the motor 14 via a reducer 17. The pinion gear 16 rotates while meshing with the rack gear 15, thereby moving the ram beam 11 in the furnace length direction. The motor 14 is an engine that applies a force to the ram beam 11 to move it in the furnace length direction.

[0047] [Anomaly detection method] The abnormality detection method according to this embodiment is a coke oven abnormality detection method for detecting an abnormality when pushing out coke in the coke oven chamber 80 from the coke oven chamber 80 using the pusher 10. FIG. 8 is a flow diagram showing the coke oven abnormality detection method according to this embodiment. Referring to FIG. 8, the abnormality detection method according to this embodiment includes a pushing step (#5), a measuring step (#10), and a determining step (#15).

[0048] In the pushing step (#5), the motor 14 drives the ram beam 11 of the pusher 10 to move in the furnace length direction, and the ram head 12 pushes the coke out of the coke chamber 80. The pushed coke is discharged outside the furnace. The pushing step (#5) will be described below with reference to Figures 9 to 11. For ease of explanation, some components of the extruder 10 are not shown in Figures 9 to 11. Also, Figures 9 to 11 show the position of the ram head 12 relative to the extruder-side kiln port 81 during the pushing step (#5), i.e., the movement amount x of the ram head 12 from the extruder-side kiln port 81 of the coke chamber 80. This movement amount x is expressed as a relative value when the distance from the extruder-side kiln port 81 to the guide car-side kiln port 82, i.e., the total length of the coke chamber 80 in the furnace length direction, is set to 100. In other words, the movement amount x of the ram head 12 is expressed as a relative value to the total length of the coke chamber 80 in the furnace length direction.

[0049] Figure 9 is a schematic diagram showing the pushing step (#5). Figure 9 shows the state at the start of the pushing step (#5), that is, just before the ram head 12 starts to contact the coke 20 in the carbonization chamber 80. Referring to Figure 9, at the start of the pushing step (#5), the position of the tip of the ram head 12 coincides with the position of the pusher-side kiln opening 81. At this time, the movement amount x of the ram head 12 from the pusher-side kiln opening 81 is 0.

[0050] Figure 10 is a schematic diagram showing the extrusion process (#5). Figure 10 shows the state immediately before the slide shoe 13 enters the coking chamber 80. Referring to Figure 10, the amount of movement x of the ram head 12 from the extruder-side kiln port 81 immediately before the slide shoe 13 enters the coking chamber 80 is a. The amount of movement a of the ram head 12 at this time corresponds to the length from the tip of the ram head 12 to the tip of the slide shoe 13.

[0051] The magnitude of the movement amount a of the ram head 12 immediately before the slide shoe 13 enters the coking chamber 80, i.e., the length from the tip of the ram head 12 to the tip of the slide shoe 13, is not particularly limited. The length from the tip of the ram head 12 to the tip of the slide shoe 13 is, for example, 3.6 m.

[0052] Normally, when the coke 20 is pushed out, the coke 20 starts moving before the slide shoe 13 enters the coke chamber 80. It can also be said that the compression of the coke 20 is completed before the slide shoe 13 enters the coke chamber 80. The compression of the coke 20 is completed in, for example, 1 to 2 m. Therefore, when the movement amount x of the ram head 12 is a, the initial peak of the pushing load has passed.

[0053] Fig. 11 is a schematic diagram showing the state of the pushing step (#5). Fig. 11 shows the state at the end of the pushing step (#5), that is, when the pushing of the coke 20 from the carbonization chamber 80 is completed. Referring to Fig. 11, at the end of the pushing step (#5), the position of the tip of the ram head 12 coincides with the position of the guide car side kiln opening 82. At this time, the movement amount x of the ram head 12 from the pusher side kiln opening 81 is 100.

[0054] During the pushing step (#5), a reaction force acts on the pusher 10. This reaction force corresponds to the pushing load of the motor 14 of the pusher 10. In the measurement step (#10), the pushing load F(x) of the motor 14 is measured for the amount of movement x of the ram head 12 in the furnace length direction during the pushing step (#5). In short, in the measurement step (#10), the pushing waveform is measured while the coke 20 is being pushed. The pushing load F(x) can be measured by detecting the torque of the motor 14.

[0055] The method for displaying the extrusion waveform measured in the measurement step (#10) is not particularly limited. For example, the extrusion waveform may be displayed as is, as shown in Figures 1 to 4. Alternatively, a contour diagram may be created in which the extrusion load F(x) for each movement amount x of the ram head 12 is represented by a different color. When creating a contour diagram, the horizontal axis of the extrusion waveform, i.e., the movement amount of the ram head 12, is divided into predetermined sections, and the average value of the extrusion load F(x) within each section is calculated. Then, the calculated average value of the extrusion load F(x) is color-coded according to the magnitude, and the calculated values ​​are displayed in chronological order.

[0056] In the judgment step (#15), if a predetermined condition is met during the pushing step (#5), it is judged that an abnormality has occurred in the coke oven. Specifically, in the judgment step (#15), if the pushing load F(x) satisfies the above formula (1) in the range of a≦x≦100 and the pushing load average F A If satisfies the above formula (2), it is determined that an abnormality has occurred in the coke oven. Formulas (1) and (2) will be explained below.

[0057] Equation (1) means that the pushing load F(x) after the slide shoe 13 has entered the coking chamber 80 (a≦x≦100) is greater than the pushing load F(a) immediately before the slide shoe 13 enters the coking chamber 80 (x=a). In other words, the judgment using equation (1) determines whether the pushing load F(x) of the motor 14 becomes greater than F(a) while the extruder 10 is pushed from the state shown in FIG. 10 to the state shown in FIG. 11. In equation (1), the pushing load F(x) is an instantaneous value, i.e., the pushing load at the moment when the movement amount of the ram head 12 is x. In other words, equation (1) is satisfied if the pushing load F(x) becomes greater than F(a) instantaneously.

[0058] Fig. 12 is a diagram showing an example of a pushing waveform of a coke oven. In the pushing waveform shown in Fig. 12, a peak of the pushing load appears during the actual pushing period, similar to the pushing waveform shown in Fig. 4. Therefore, in Fig. 12, the pushing load F(x) during the actual pushing period is larger than the pushing load F(a) when the movement amount of the ram head 12 is a. Therefore, in the example shown in Fig. 12, the pushing load F(x) satisfies formula (1).

[0059] FIG. 13 is a diagram showing an example of the extrusion waveform of a coke oven. The extrusion waveform shown in FIG. 13 is the same as the extrusion waveform shown in FIG. 12. In FIG. 13, the horizontal axis, i.e., the movement amount of the ram head 12 when the total length of the coking chamber 80 in the furnace length direction is set to 100 (a≦x≦100), is divided into predetermined sections. In the example shown in FIG. 13, the width of one divided section is 5. This corresponds to dividing the coking chamber 80 into sections where the dimension in the furnace top direction is 5% of the total length of the coking chamber 80 in the range of a≦x≦100.

[0060] Equation (2) is the average value of the pushing load F(x) in the Ath section among the divided sections, and is the pushing load average F A As this extrusion load average F A is greater than the pushing load F(a) just before the slide shoe 13 enters the coking chamber 80 (x=a). AUnlike the extrusion load F(x), which is an instantaneous value, F(x) is the average value of the extrusion load F(x) within the A-th section. In the judgment using equation (2), it is judged whether the extrusion load average within any section becomes larger than F(a) while the extruder 10 is being pushed from the state shown in FIG. 10 to the state shown in FIG. 11. In the example shown in FIG. 13, the extrusion load average F(x) within the A-th section is A satisfies equation (2).

[0061] In the example of this embodiment, in the judgment step (#15), it is determined whether the pushing load F(x) satisfies the formula (1) and the pushing load average F A satisfies formula (2), it is determined that an abnormality has occurred in the coke oven. However, it is not necessary to satisfy both formulas (1) and (2). For example, it is also possible to use only formula (1) to determine whether an abnormality has occurred in the coke oven. In other words, it is also possible to determine whether an abnormality has occurred in the coke oven when the pushing load F(x) satisfies formula (1).

[0062] If it is determined in the determination step (#15) during the pushing step (#5) that an abnormality has occurred in the coke oven, it is presumed that coke lumps that spilled out between the ram head 12 of the pusher 10 and the oven wall 85 during the pushing of the coke 20 have accumulated on the oven bottom 84. In this case, it is not necessarily necessary to immediately stop the pusher 10. If it is determined in the determination step (#15) that an abnormality has occurred in the coke oven, the coke lumps in the coke oven may be discharged after the current pushing of the coke 20 is completed. Alternatively, the width of the ram head 12 of the pusher 10 may be increased by repair or replacement after the current pushing of the coke 20 is completed. This is because if the width of the ram head 12 is increased, the clearance between the ram head 12 and the oven wall 85 during the pushing step (#5) becomes smaller, making it more difficult for the coke lumps to spill out.

[0063] [effect] In the abnormality detection method according to this embodiment, in the determination step (#15), if the pushing load F(x) satisfies formula (1) within the range of a≦x≦100, it is determined that an abnormality has occurred in the coke oven. That is, in the abnormality detection method according to this embodiment, if the pushing load F(x) after the slide shoe 13 enters the coke chamber 80 (a≦x≦100) is greater than the pushing load F(a) immediately before the slide shoe 13 enters the coke chamber 80 (x=a), it is determined that an abnormality has occurred in the coke oven. As shown in FIGS. 3 and 4, in the pushing waveform when an abnormality has occurred in the coke oven, a peak appears in the pushing load F(x) during the actual pushing period, or the waveform changes after the initial peak. In the abnormality detection method according to this embodiment, if such a pushing waveform is measured during the pushing of coke 20, it can be determined that an abnormality has occurred. Therefore, the anomaly detection method according to this embodiment can detect anomalies in a coke oven that have not been considered in the past (specifically, an anomaly that occurs when a lump of coke spills out from between the pusher 10 and the oven wall 85 during the extrusion of the coke 20 and remains in the oven). Therefore, the anomaly detection method according to this embodiment can detect anomalies in a coke oven with high accuracy.

[0064] In the abnormality detection method according to this embodiment, if the formula (2) is satisfied in addition to the formula (1), it may be determined that an abnormality exists inside the coke oven. If the formula (2) is satisfied, the pushing load average F(x) obtained by averaging the pushing loads F(x) within the divided sections is used. Abecomes larger than the pushing load F(a) immediately before the slide shoe 13 enters the coke chamber 80 (x=a). In other words, the abnormality detection method of this embodiment determines that an abnormality has occurred in the coke oven not only when the pushing load F(x) momentarily becomes larger than F(a) but also when the average value of the pushing load F(x) within a section is larger than F(a). The abnormality detection method of this embodiment does not determine an abnormality simply when the pushing load F(x) momentarily becomes larger than F(a). This state is simply a momentary increase in the pushing load F(x), so it may be within a normal range and does not necessarily indicate that an abnormality has occurred. Therefore, the abnormality detection method of this embodiment can reduce the risk of erroneous detection.

[0065] [Second embodiment] The anomaly detection method according to this embodiment differs from the anomaly detection method according to the first embodiment in the conditions for determining that an abnormality has occurred in the coke oven in the determination step (#15). Specifically, in the determination step (#15) of the anomaly detection method according to this embodiment, if the pushing load F(x) satisfies the formula (3) in addition to the formulas (1) and (2) within the range of a≦x≦100, it is determined that an abnormality has occurred inside the coke oven.

[0066] Equation (3) is the average pushing load F(x) in the Ath section of the divided sections. A and the average pushing load F(x) in the (A+1)th section A+1 means that both are greater than the pushing load F(a) just before the slide shoe 13 enters the coking chamber 80 (x=a). A+1 Unlike the pushing load F(x), which is an instantaneous value, is the average value of the pushing load F(x) within the (A+1)th section. Equation (3) further defines the pushing load average F within the (A+1)th section. A+1 is the average extrusion load F in the Ath section A means greater than.

[0067] In the judgment using formula (3), it is judged whether the extrusion load average becomes larger than F(a) in two consecutive sections while the extruder 10 is being pushed from the state shown in Fig. 10 to the state shown in Fig. 11. Furthermore, in the judgment using formula (3), when the consecutive sections are the A-th section and the (A+1)-th section, the extrusion load average F in the (A+1)-th section is judged. A+1 is the average pushing load F in the Ath section A Determine whether it is greater than

[0068] In the anomaly detection method according to this embodiment, if formula (3) is satisfied in addition to formulas (1) and (2), it is determined that an abnormality has occurred inside the coke oven. In short, the anomaly detection method according to this embodiment has stricter conditions for determining that an abnormality has occurred inside the coke oven than the anomaly detection method according to the first embodiment. Therefore, the anomaly detection method according to this embodiment further reduces the risk of false detection.

[0069] [Third embodiment] The anomaly detection method according to this embodiment differs from the anomaly detection method according to the first embodiment in the condition for determining that an anomaly has occurred in the coke oven in the determination step (#15). Specifically, in the determination step (#15) of the anomaly detection method according to this embodiment, it is determined that an anomaly has occurred in the coke oven when the pushing load F(x) satisfies the above formula (4) in the range of a≦x≦100.

[0070] The left side of equation (4) represents the work done by the motor 14 of the extruder 10 when the position of the ram head 12 is moved from a to x. Also, on the right side of equation (4), S min means the minimum value of the work S done by the motor 14 of the extruder 10 when the position of the ram head 12 is moved from a to 100 in the past extrusion of the coke 20 in the carbonization chamber 80. In other words, every time the extrusion of the coke 20 in the carbonization chamber 80 is completed, the work S done by the motor 14 is recorded, and the minimum value of the work S recorded so far is set as S min In the determination using the formula (4), the work done by the motor 14 of the extruder 10 during the extrusion step (#5) is S minDetermine whether it is greater than 1.2 times the value of

[0071] In the abnormality detection method of this embodiment, during the extrusion step (#5), the work done by the motor 14 of the extruder 10 in the range of a≦x≦100 is S min When the extrusion load F(x) is greater than 1.2 times the extrusion load F(x), it is determined that an abnormality has occurred in the coke oven. In the extrusion waveform when an abnormality has occurred in the coke oven, as shown in FIGS. 3 and 4, a peak appears in the extrusion load F(x) during the actual extrusion period, or the waveform changes after the initial peak. The work done by the extruder 10 when such an extrusion waveform is observed is much greater than the work done by the extruder 10 when the coke oven is in a healthy state. Therefore, the abnormality detection method of this embodiment can determine that an abnormality has occurred when such an extrusion waveform is measured during the extrusion of coke 20. Therefore, the abnormality detection method of this embodiment can detect abnormalities in the coke oven with high accuracy, similar to the abnormality detection method of the first embodiment. [Example]

[0072] [First Example] To confirm the effectiveness of the anomaly detection method according to this embodiment, coke was actually pushed in a coke chamber and the pushing waveform was measured. The dimensions of the coke chamber in which the coke was pushed were 0.46 m wide, 16 m long in the furnace length direction, and 7.125 m high. The length a from the tip of the ram head to the tip of the slide shoe of the pusher used to push the coke was 3.6 m. When the value of a is expressed as a relative value with the total length of the coke chamber in the furnace length direction taken as 100, it is 3.6 ÷ 16 × 100 ≒ 22.

[0073] FIG. 14 is a diagram showing the extrusion waveform according to this embodiment. FIG. 14 shows four patterns of extrusion waveforms A to D in the same coke chamber. In FIG. 14, the extrusion waveform A is the extrusion waveform when the inside of the furnace is in a healthy state. On the other hand, the extrusion waveforms B to D are the extrusion waveforms when an abnormality occurs in the furnace. In the extrusion waveforms B to D, all of them show a peak in the extrusion load during the actual extrusion period. Among B to D, the extrusion waveform D has the largest extrusion load. In the extrusion waveform D, coke packing occurs when the amount of movement of the ram head is 90 (a relative value to the total length of the coke chamber).

[0074] In the first example, it was verified whether or not the extrusion waveforms A to D shown in FIG. 14 were judged to be an abnormality in the coke oven when the abnormality detection method according to each embodiment was used.

[0075] Table 1 summarizes the verification results in Example 1. Table 1 shows the results when the anomaly detection method according to the first embodiment was used for extrusion waveforms A to D. However, in this Example, only formula (1) was used for the judgment. In Table 1, if the extrusion waveform was judged to be abnormal, it is marked as "Yes," and if not, it is marked as "No."

[0076] [Table 1]

[0077] Table 1 shows the extrusion load F(a) for each of the extrusion waveforms A to D. Table 1 also shows the movement amount x of the ram head when the extrusion waveform was first determined to be abnormal, that is, when formula (1) was first satisfied in the range of a≦x≦100. Referring to the results of Table 1, when the abnormality detection method according to the first embodiment is used, the extrusion waveform A is not determined to be abnormal. On the other hand, the extrusion waveforms B to D are determined to be abnormal. Therefore, from the results of Table 1, it is clear that the occurrence of abnormal extrusion waveforms such as the extrusion waveforms B to D can be detected by using the abnormality detection method according to the first embodiment.

[0078] Table 2 summarizes the verification results of Example 1. Table 2 shows the results when the anomaly detection method according to the third embodiment was used on extrusion waveforms A to D. In Table 2, if the extrusion waveform was determined to be abnormal, it is marked "Yes," and if not, it is marked "No."

[0079] [Table 2]

[0080] Table 2 shows the workload of the extruder motor for each of the extrusion waveforms A to D in the range of a≦x≦100. However, for extrusion waveform D, jamming occurs when the ram head travels x=90, so for extrusion waveform D, the workload of the extruder motor is shown in the range of a≦x≦90. Table 2 also shows the workload for each extrusion waveform relative to the workload for extrusion waveform A. Referring to the results in Table 2, the workloads for extrusion waveforms B to D are all 1.2 times or more the workload for extrusion waveform A. Therefore, when the abnormality detection method according to the third embodiment is used, extrusion waveforms B to D are determined to be abnormal. Therefore, from the results in Table 2, the abnormality detection method according to the third embodiment can detect the occurrence of abnormal extrusion waveforms such as extrusion waveforms B to D. Note that when this detection method is used, abnormalities in the extrusion waveform can be detected sequentially even if the extrusion process is not completed.

[0081] [Second Example] In this example, we investigated the effect of coke lumps that spilled out between the ram head of the extruder and the furnace wall during coke extrusion and accumulated on the hearth, on the extrusion load during coke extrusion. Figure 15 is a diagram showing the transition of the coke lump pile height depending on the ram head position. Figure 15 shows the transition of the coke lump pile height in the same coke chamber on different measurement days. In Figure 15, the horizontal axis shows the position of the ram head (actual measured value) relative to the extruder-side furnace mouth, and the vertical axis shows the height of the coke lumps accumulated on the hearth.

[0082] Fig. 16 is a diagram showing the relationship between the pile height of the lump coke and the pushing load. Fig. 16 shows the pile height of the lump coke and the peak value of the pushing load when the peak of the pushing load appears during the actual pushing period in the pushing waveform during coke pushing. In Fig. 16, the horizontal axis represents the peak value of the pushing load during the actual pushing period, and the vertical axis represents the height of the lump coke piled on the hearth.

[0083] Referring to Figure 16, when the peak of the pushing load appears during the actual pushing period, the coke lumps have accumulated to a height of 500 mm or more. Also, referring to Figures 15 and 16, when coke packing occurs, the coke lumps have accumulated to a height of 1000 mm or more. At this time, the peak value of the pushing load is approximately 0.8, indicating that a very large pushing load has occurred. This indicates that there is a good correlation between the height of the coke lumps accumulated at the hearth and the peak value of the pushing load during the actual pushing period. Therefore, when the height of the coke lumps in the furnace increases, a characteristic change occurs in the pushing waveform. By focusing on this change, it is possible to detect early deterioration of the coke's pushability.

[0084] The embodiments of the present disclosure have been described above. However, the above-described embodiments are merely examples for implementing the present disclosure. Therefore, the present disclosure is not limited to the above-described embodiments, and can be implemented by appropriately modifying the above-described embodiments within the scope of the present disclosure. [Explanation of symbols]

[0085] 10: Extruder 11: Ram Beam 12: Ramhead 13: Slide shoe 14: Motor (engine) 80: Carbonization chamber

Claims

1. A method for detecting an abnormality in a coke oven, which detects an abnormality when pushing coke in a coke oven chamber out of the coke oven chamber using a pusher including: a ram beam extending in a furnace length direction; a ram head fixed to a tip of the ram beam; a slide shoe disposed below the ram beam and integrated with the ram beam; and a mechanism that applies a force to move the ram beam in the furnace length direction, a pushing step of moving the ram beam in the furnace length direction and pushing the coke out of the carbonization chamber with the ram head; a measuring step of measuring a thrust load F(x) of the engine at a position x, where x is a position of the ram head in the furnace length direction during the thrusting step; and a determination step of determining that an abnormality has occurred in the coke oven if the pushing load F(x) measured in the measurement step satisfies the following formula (1) in the range of a≦x≦100. [Equation 1] However, the position of the ram head just before it starts to contact the coke is x = 0, the position of the ram head just before the slide shoe enters the carbonization chamber is x = a, and the position of the ram head at the time when the pushing of the coke from the carbonization chamber is completed is x = 100.

2. The anomaly detection method according to claim 1, In the determination step, the coking chamber is further divided into sections in the range of a≦x≦100, each section having a dimension in the furnace length direction that is 5% of the total length of the coking chamber, and the average value of the pushing load F(x) in the Ath section is defined as the pushing load average F Ａ When the extrusion load average F Ａ The anomaly detection method determines that an abnormality has occurred in the coke oven if the following formula (2) is satisfied: [Equation 2]

3. The anomaly detection method according to claim 2, In the determination step, the pushing load F(x) in the (A+1)th section is further averaged to obtain a pushing load average F Ａ＋１ When the extrusion load average F Ａ and F Ａ＋１ The anomaly detection method determines that an abnormality has occurred in the coke oven if the following formula (3) is satisfied: [Equation 3]

4. A method for detecting an abnormality in a coke oven, which detects an abnormality when pushing coke in a coke oven chamber out of the coke oven chamber using a pusher including: a ram beam extending in a furnace length direction; a ram head fixed to a tip of the ram beam; a slide shoe disposed below the ram beam and integrated with the ram beam; and a mechanism that applies a force to move the ram beam in the furnace length direction, a pushing step of moving the ram beam in the furnace length direction and pushing the coke out of the carbonization chamber with the ram head; a measuring step of measuring a thrust load F(x) of the engine at a position x, where x is a position of the ram head in the furnace length direction during the thrusting step; and a determination step of determining that an abnormality has occurred in the coke oven if the pushing load F(x) measured in the measurement step satisfies the following formula (4) in the range of a≦x≦100. [Equation 4] However, the position of the ram head just before the ram head starts to contact the coke is defined as x = 0, the position of the ram head just before the slide shoe enters the coke chamber is defined as x = a, and the position of the ram head at the time when the pushing of the coke from the coke chamber is completed is defined as x = 100. In the past pushing of the coke in the coke chamber, the minimum value of the work S done by the engine when the position of the ram head is moved from x = a to x = 100 is defined as S. ｍｉｎ Let's say.

Images