State measuring system and state measuring method in blast furnace

Abstract

To provide a state measuring system and a state measuring method in a blast furnace capable of measuring a state in the blast furnace so as to follow its change.SOLUTION: A state measuring system 1 in a blast furnace 100 includes: a first detector 10 and a second detector 20 arranged on both sides of a measurement target portion on a path 40 passing through the measurement target portion in the blast furnace 100; and a measuring device 30. The first detector 10 detects a cosmic ray particle flying along the path 40 before entering the measurement target portion as a flying particle. The second detector 20 detects the flying particle having passed through the measurement target portion as a transmitted particle. The measuring device 30 measures the time variation of a state of the measurement target portion on the basis of time variations of detection results of the flying particle and the transmitted particle.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to a condition measurement system and a condition measurement method in a blast furnace. [Background technology]

[0002] Stable operation of a blast furnace requires that the molten pig iron and molten slag produced in the blast furnace be discharged in the exact amounts produced. If the molten pig iron and molten slag produced in the blast furnace cannot be completely discharged, they will remain in the furnace. When the molten pig iron and molten slag reach the height of the blast tuyeres, blasting to the blast furnace becomes impossible, making continuous operation difficult. Therefore, it is necessary to constantly manage the production volume and the discharge volume to prevent the amount of molten material remaining in the blast furnace from increasing. A typical method for estimating the production volume of molten pig iron and molten slag is to assume that the molten pig iron and molten slag are produced in the blast furnace in the amount of raw materials charged into the blast furnace per unit time. Another method for estimating the discharge volume is to estimate it from the weight increase of the torpedo car, hot metal ladle, or slag ladle that receives the molten pig iron and molten slag discharged from the blast furnace. The difference between the production amount estimated by these methods and the discharge amount can be calculated as an estimate of the amount of molten iron and molten slag remaining in the furnace.

[0003] On the other hand, the area in the blast furnace where the molten pig iron and molten slag are retained is considered to be the gaps in the coke packed bed. The gap volume in the coke packed bed, or the so-called void volume, varies depending on the quality of the coke. Therefore, the void volume varies depending on the operation timing. As a result, it is difficult to accurately determine the position of the upper end of the liquid surface of the molten material based solely on the retained volume of molten pig iron and molten slag estimated by the above-mentioned method. Therefore, various methods for estimating the position of the upper end of the liquid surface (liquid surface level) using a sensor have been investigated.

[0004] For example, Patent Document 1 discloses a technology for measuring the thickness of refractory materials inside a blast furnace by using a detector set consisting of three plastic flat plates to measure the intensity of cosmic ray muons that pass through the blast furnace at a specific angle of incidence for a predetermined period of time, such as 50 days.

[0005] Patent Document 2 discloses a method for estimating the state inside a blast furnace, which involves using a measuring device to measure cosmic ray muons to accumulate for a certain period of time the intensity of cosmic ray muons that pass through the blast furnace, information on the direction of arrival of the cosmic ray muons that pass through the blast furnace, and the intensity of non-penetrating cosmic ray muons that do not pass through the blast furnace, and based on the accumulated data from these measurements, expressing the state of the blast furnace as density by the intensity ratio between the intensity of cosmic ray muons that pass through the hearth and the intensity of non-penetrating cosmic ray muons, and determining the density of the furnace fill from the intensity ratio of the furnace fill that forms a boundary with the intensity ratio estimated to be the refractory of the blast furnace, and estimating the fill.

[0006] Furthermore, Patent Document 3 discloses a method for 3D visualization of the structure of a structure at the point where the trajectory changes by measuring the change in trajectory due to Coulomb multiple scattering that occurs when a muon passes through a material in the structure. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Publication No. 8-261741 [Patent Document 2] Japanese Patent Application Laid-Open No. 2008-145141 [Patent Document 3] Japanese Patent Application Laid-Open No. 2017-53705 Summary of the Invention [Problem to be solved by the invention]

[0008] As mentioned above, estimating the liquid level in a blast furnace is important, and several measurement methods have been proposed to help estimate the liquid level. The tapping operation in a blast furnace takes approximately two to four hours per operation. If a discharge failure occurs due to a problem with the tapping operation, it is necessary to be able to detect the liquid level within a time span of several hours, or at most one day.

[0009] However, when estimating the state inside a blast furnace by accumulating data as described in Patent Document 1 or 2, it takes time to accumulate sufficient data. For example, a single measurement may take several days to several dozen days. As a result, the state inside the blast furnace changes while the data is being accumulated and a single measurement is being performed. It is therefore necessary to measure the state inside the blast furnace so as to follow these changes.

[0010] Furthermore, in the method described in Patent Document 3, data processing is performed assuming that scattering occurs at a single location. However, in a blast furnace, which is composed of many materials, it is thought that the trajectory of the muon changes depending on the material, making it difficult to apply this assumption. Furthermore, it is difficult to identify in which material scattering occurred using this method. Furthermore, this method assumes that measurements are taken multiple times while changing the location of one pair of detectors. However, given that the liquid level in a blast furnace changes from moment to moment, there is a possibility that the structure will change while the sensor position is changed, making this method unsuitable for accurate measurements.

[0011] Therefore, an object of the present disclosure is to provide a state measurement system and a state measurement method inside a blast furnace that can measure the state inside the blast furnace so as to follow changes in the state. [Means for solving the problem]

[0012] (1) A system for measuring a condition inside a blast furnace according to one embodiment of the present disclosure includes a first detector and a second detector arranged on either side of a measurement target portion inside the blast furnace along a path passing through the measurement target portion, and a measurement device. The first detector detects cosmic ray particles that arrive along the path and before they enter the measurement target portion as incoming particles. The second detector detects the incoming particles that have passed through the measurement target portion as passing particles. The measurement device measures changes over time in the condition of the measurement target portion based on changes over time in the detection results of the incoming particles and the passing particles.

[0013] (2) In the condition measurement system inside a blast furnace described in (1) above, the measurement device may measure the change over time in the density of material present in the measurement target portion based on the change in the number of cosmic ray particles detected as the incoming particles by the first detector and also detected as the passing particles by the second detector.

[0014] (3) In the condition measurement system inside a blast furnace described in (2) above, the measurement device may calculate the change over time in the rate at which cosmic ray particles pass through the measurement target portion based on the change in the number of cosmic ray particles detected as the incoming particles by the first detector and also detected as the passing particles by the second detector, and measure the change over time in the density of material present in the measurement target portion based on the change over time in the calculated rate.

[0015] (4) In the system for measuring a state inside a blast furnace described in (2) or (3) above, the first detector or the second detector may measure the energy of incident cosmic ray particles. The measurement device may measure a change over time in the density of a substance present in the measurement target portion based on a change over time in the number of cosmic ray particles having a predetermined energy that pass through the measurement target portion.

[0016] (5) The condition measurement system for a blast furnace described in any one of (1) to (4) above may further include a deflector that deflects the trajectory of cosmic ray particles that have energies outside a predetermined range among the cosmic ray particles that arrive along the path.

[0017] (6) In the condition measurement system inside a blast furnace described in any one of (1) to (5) above, the first detector and the second detector may be installed to detect cosmic ray particles coming from an elevation angle in the range of 40 degrees or more and 60 degrees or less.

[0018] (7) The system for measuring a condition inside a blast furnace according to any one of (1) to (6) above may include at least two pairs of the first detector and the second detector. Each pair of the first detector and the second detector may be installed such that the second detector is located at a different height between the height of the tuyere of the blast furnace and the height of the taphole of the blast furnace.

[0019] (8) A method for measuring the state inside a blast furnace according to one embodiment of the present disclosure includes the steps of detecting incoming particles, which are cosmic ray particles that fly along a path passing through a portion to be measured inside the blast furnace and before they are incident on the portion to be measured, detecting passing particles, which are the incoming particles that have passed through the portion to be measured, and measuring the change over time in the state of the portion to be measured based on the change over time in the detection results of the incoming particles and the passing particles. [Effects of the Invention]

[0020] According to the system and method for measuring a state inside a blast furnace according to the present disclosure, the state inside a blast furnace can be measured so as to follow changes therein. [Brief explanation of the drawings]

[0021] [Figure 1] 1 is a block diagram illustrating an example configuration of a measurement system according to the present disclosure. [Figure 2] FIG. 2 is a cross-sectional view showing an example of the internal state of a blast furnace to be measured. [Figure 3] FIG. 10 is a cross-sectional view showing an example of the configuration of a detector for detecting the direction in which particles fly. [Figure 4] 10 is a graph showing an example of the relationship between the elevation angle of a detector and a detection value. [Figure 5] 10 is a graph showing an example of the relationship between the energy of a particle and the difference in the detected value of the particle. [Figure 6] 1 is a graph showing an example of the relationship between the ratio of the detected value of passing particles to the detected value of flying particles and the normalized liquid surface level in a blast furnace. [Figure 7] 1 is a flowchart illustrating an example of a procedure for a state measurement method according to the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0022] Hereinafter, embodiments of a measurement system 1 (see FIG. 1, etc.) and a measurement method according to the present disclosure will be described with reference to the drawings. Each drawing is a schematic diagram and may differ from the actual product. Furthermore, the following embodiments exemplify devices or methods for embodying the technical ideas of the present disclosure, and are not intended to limit the configuration to those described below. In other words, the technical ideas of the present disclosure can be modified in various ways within the technical scope described in the claims.

[0023] (Example of measurement system 1 configuration) As shown in FIG. 1, a measurement system 1 according to one embodiment includes a first detector 10, a second detector 20, and a measurement device 30. As shown in FIG. 2, the first detector 10 and the second detector 20 are installed outside the blast furnace 100 so that a path 40 of cosmic ray particles approaching the blast furnace 100 passes through the liquid layer surface of the slag 150. The first detector 10 is located on the side of the blast furnace 100 from which the cosmic ray particles are approaching and detects cosmic ray particles before they enter the blast furnace 100. Cosmic ray particles before they enter the blast furnace 100 are also referred to as incoming particles. The second detector 20 is located on the side of the blast furnace 100 from which the cosmic ray particles are approaching and detects cosmic ray particles that have passed through the blast furnace 100. The second detector 20 is installed near the bottom of the furnace so as to pass through the liquid layer surface of the slag 150. Cosmic ray particles that have passed through the blast furnace 100 are also referred to as passing particles. The measurement device 30 measures the internal state of the blast furnace 100 based on the detection results of cosmic ray particles by the first detector 10 and the second detector 20. The measurement system 1 is also called a state measurement system. The measurement device 30 is also called a state measurement device.

[0024] The measurement system 1 according to this embodiment measures muon particles as cosmic ray particles. The cosmic ray particles that the measurement system 1 measures are not limited to muon particles, but may include various other particles such as alpha rays or beta rays. The measurement system 1 is not limited to measuring particles, and may also measure electromagnetic waves such as gamma rays or X-rays.

[0025] <Measuring device 30> The measurement device 30 includes a control unit 32. The control unit 32 may include at least one processor, such as a CPU (Central Processing Unit) or a GPU (Graphics Processing Unit), to control and manage various functions of the information processing device 4. The control unit 32 may be configured with one processor or multiple processors. The processor constituting the control unit 32 may implement the functions of the information processing device 4 by reading and executing a program stored in a storage unit (described later).

[0026] The control unit 32 may include a memory unit. The memory unit stores various types of information or data. The memory unit may store, for example, a program executed by the control unit 32, or data used in processing executed by the control unit 32, or processing results. The memory unit may also function as a work memory for the control unit 32. The memory unit may be configured to include, for example, a semiconductor memory, but is not limited to this. For example, the memory unit may be configured as an internal memory of a processor used as the control unit 32, or as a hard disk drive (HDD) accessible from the control unit 32. The memory unit may be configured as a non-transitory readable medium. The memory unit may be configured integrally with the control unit 32, or may be configured separately from the control unit 32.

[0027] The measurement device 30 may further include a display unit 34, although this is not essential. The display unit 34 may notify the user of information by outputting visual information such as text, graphics, or images. The display unit 34 may include a display device or may be connected to the display device via a wired or wireless connection. The display device may include various displays, such as a liquid crystal display.

[0028] The measuring device 30 further includes a communication unit 36, although this is not essential. The communication unit 36 ​​may include a communication interface for communicating with other devices via a wired or wireless connection. The communication interface may be configured to communicate with other devices via a network. The communication unit 36 ​​may include an input / output port for inputting and outputting data to and from other devices. The communication unit 36 ​​transmits and receives necessary data and signals to and from a process computer or a higher-level system. The communication unit 36 ​​may communicate based on a wired communication standard or a wireless communication standard. For example, the wireless communication standard may include cellular phone communication standards such as 3G, 4G, and 5G. Furthermore, for example, the wireless communication standard may include IEEE 802.11, Bluetooth (registered trademark), and the like. The communication unit 36 ​​may support one or more of these communication standards. The communication unit 36 ​​is not limited to these examples and may communicate with other devices or input and output data based on various standards.

[0029] The measuring device 30 may include an audio output device such as a speaker, or may include various other output devices. The measuring device 30 may further include an input device that accepts input from a user. The input device may include, for example, a keyboard or physical keys, or may include a touch panel, a touch sensor, or a pointing device such as a mouse. The input device is not limited to these examples and may include various other devices.

[0030] <Blast Furnace 100> As shown in FIG. 2, the blast furnace 100, the state of which is measured by the measuring device 30, includes a furnace body 110, a tuyere 120, and a tap hole 130. The blast furnace 100 melts raw materials 140, which are charged from the top of the furnace body 110, using high-temperature air blown from the tuyere 120. The raw materials 140 include iron ore, coke, and the like. The molten raw materials 140 contain slag 150 and pig iron 160, and accumulate at the bottom of the furnace body 110. The density of the pig iron 160 is lower than that of the slag 150. Therefore, the pig iron 160 accumulates below the slag 150 at the bottom of the furnace body 110. The slag 150 and pig iron 160 are discharged to the outside through the tap hole 130.

[0031] In the blast furnace 100, when the liquid level (height of the liquid surface) of the molten material rises to the height of the tuyere 120, it becomes impossible to blow high-temperature air from the tuyere 120, and the blast furnace 100 cannot operate. Conversely, when the liquid level of the molten material drops to the height of the taphole 130, air is entrained when the molten material is discharged from the taphole 130, making it difficult to continue stable tapping of the pig iron 160. Therefore, it becomes necessary to take measures such as closing the taphole 130 located at the height of the liquid level of the molten material and using a new, different opening as the taphole 130.

[0032] <First Detector 10 and Second Detector 20> The first detector 10 and the second detector 20 are installed outside the furnace body 110. The first detector 10 and the second detector 20 detect cosmic ray particles entering the blast furnace 100 so that the measuring device 30 can measure the liquid level of the molten material inside the blast furnace 100.

[0033] Cosmic ray particles can come from any direction. The number of cosmic ray particles coming from the zenith direction is greater than the number of cosmic ray particles coming from the horizontal direction or from underground. The greater the angle (elevation angle) at which the direction from which the cosmic ray particles come is tilted upward from the horizontal, the greater the number of cosmic ray particles coming.

[0034] The first detector 10 and the second detector 20 detect cosmic ray particles traveling along a path 40 shown in Fig. 2. The path 40 is represented as a straight line that is inclined upward from the horizontal direction at an angle (elevation angle) of θ.

[0035] As shown in FIG. 3, the first detector 10 includes a first panel 11 and a second panel 12. The first panel 11 and the second panel 12 are configured to include a plurality of cells arranged along the XY plane. Each cell is configured to be able to detect the passage of a cosmic ray particle. Each cell may be configured to include, for example, a light-emitting element such as a phosphor that emits light when a cosmic ray particle passes through, and a light-receiving element that detects the emission. A cell that emits light when a cosmic ray particle passes through is represented as an emitting cell 15.

[0036] When a cosmic ray particle passes along a path 41 that extends perpendicular to the first panel 11 and the second panel 12, the coordinates of the light emitting cells 15 in the XY plane of the first panel 11 and the coordinates of the light emitting cells 15 in the XY plane of the second panel 12 match. On the other hand, when a cosmic ray particle passes along a path 42 that is inclined with respect to the first panel 11 and the second panel 12, the coordinates of the light emitting cells 15 in the XY plane of the first panel 11 and the coordinates of the light emitting cells 15 in the XY plane of the second panel 12 differ. The first detector 10 can identify the direction from which the cosmic ray particle entered and passed through, based on the coordinates of the light emitting cells 15 in the first panel 11 and the coordinates of the light emitting cells 15 in the second panel 12.

[0037] The second detector 20 may be configured similarly to the first detector 10 .

[0038] In this embodiment, the first detector 10 and the second detector 20 are installed outside the blast furnace 100 so that the first panel 11 and the second panel 12 are perpendicular to the path 40 illustrated in FIG. 2 . The first detector 10 and the second detector 20 are also arranged side by side on the path 40. In this manner, when a cosmic ray particle travels along the path 40, the cosmic ray particle is detected by both the first detector 10 and the second detector 20. As a result, the measurement device 30 can determine whether the cosmic ray particle was able to pass through the blast furnace 100 or not. In other words, the measurement device 30 can measure the number of cosmic ray particles that are detected as incoming particles by the first detector 10 and also as passing particles by the second detector 20.

[0039] The orientation in which the first detector 10 and the second detector 20 are installed is not limited to the orientation in which the first panel 11 and the second panel 12 are perpendicular to the path 40, as described above. The first detector 10 and the second detector 20 may be installed so that the first panel 11 and the second panel 12 are inclined with respect to the path 40, as long as the direction in which the cosmic ray particles are traveling can be identified.

[0040] (Example of operation of measurement system 1) An example of the operation of the measurement system 1 according to this embodiment will be described below. The measurement system 1 measures the position of the liquid level of the molten material, including the slag 150 and pig iron 160, in the blast furnace 100 between the tuyere 120 and the taphole 130. The greater the integrated value of the density of a material at each point along the path 40 through which the cosmic ray particles pass, the lower the probability that the cosmic ray particles will pass through that material. The control unit 32 of the measurement device 30 can calculate the probability that the cosmic ray particles will pass through the object of measurement along the path 40 based on the proportion of cosmic ray particles detected by the first detector 10 that are also detected by the second detector 20. The control unit 32 can calculate the integrated value of the density of the object of measurement at each point along the path 40 based on the probability that the cosmic ray particles will pass through the object of measurement along the path 40. In other words, the control unit 32 can measure the change over time in the density of material present in the measurement portion based on the change in the number of cosmic ray particles that are detected as incoming particles by the first detector 10 and also detected as passing particles by the second detector 20. The control unit 32 can also calculate the change over time in the rate at which cosmic ray particles pass through the measurement portion based on the change over time in the number of cosmic ray particles that are detected as incoming particles by the first detector 10 and also detected as passing particles by the second detector 20, and can measure the change over time in the density of material present in the measurement portion based on the change over time in the calculated rate.

[0041] The measurement system 1 according to this embodiment measures the molten material, including the slag 150 and pig iron 160, accumulated in the blast furnace 100 as the measurement object. That is, the control unit 32 calculates an integrated value of the density of the molten material present at each portion along the path 40. The portion for which the integrated value of density is calculated is also referred to as the measurement object portion. The larger the integrated value of the density of the molten material present at the measurement object portion, the longer the distance that cosmic ray particles pass through the molten material along the path 40, or the higher the density of the molten material present at the measurement object portion. If it is assumed that the density of the molten material does not change much in the blast furnace 100, the larger the integrated value of the density of the molten material present at the measurement object portion, the longer the distance that cosmic ray particles pass through the molten material along the path 40. The longer the distance that cosmic ray particles pass through the molten material along the path 40, the higher the liquid level of the molten material. Therefore, the control unit 32 can measure the liquid level of the molten material based on the integrated value of the density of the molten material.

[0042] In FIG. 2 , a detector combining a first detector 10 and a second detector 20 is installed on the wall surface of the furnace body 110 of the blast furnace 100 so that a path 40 passes from the wall surface position of the raw materials 140 to the liquid surface of the molten material. In this case, the detector combining the first detector 10 and the second detector 20 detects cosmic ray particles that do not pass through the molten material when the liquid surface level of the molten material drops to the height of the taphole 130. When the detector combining the first detector 10 and the second detector 20 detects cosmic ray particles that do not pass through the molten material, the integrated value of the density of the molten material in the measurement target portion calculated by the control unit 32 becomes a small value. When the integrated value of the density of the molten material decreases, the control unit 32 can detect that the liquid surface level of the molten material has dropped to the height of the taphole 130.

[0043] The position of the detector combining the first detector 10 and the second detector 20 is not limited to the position illustrated in FIG. 2 . The detector combining the first detector 10 and the second detector 20 may be installed, for example, so that the path 40 passes slightly below the height of the tuyere 120 on the wall surface of the furnace body 110 of the blast furnace 100. In this case, the detector combining the first detector 10 and the second detector 20 detects cosmic ray particles that have passed through the molten material when the liquid level of the molten material rises to the height of the tuyere 120. When the detector combining the first detector 10 and the second detector 20 detects cosmic ray particles that have passed through the molten material, the integrated value of the density of the molten material in the measurement target portion calculated by the control unit 32 becomes a large value. When the integrated value of the density of the molten material increases, the control unit 32 can detect that the liquid level of the molten material has risen to the height of the tuyere 120.

[0044] When the first detector 10 detects a cosmic ray particle that has arrived along the path 40, the control unit 32 determines whether the second detector 20 has also detected that cosmic ray particle. Specifically, when both the first detector 10 and the second detector 20 detect a cosmic ray particle that has entered in a direction along the path 40, the control unit 32 outputs the time at which the cosmic ray particle was detected as the detection result to the measurement device 30. When the difference between the time at which the first detector 10 detects the cosmic ray particle and the time at which the second detector 20 detects the cosmic ray particle is equal to the delay time calculated based on the speed of the cosmic ray particle (the speed of light), the control unit 32 determines that the first detector 10 and the second detector 20 have detected the same cosmic ray particle.

[0045] If the first detector 10 detects a cosmic ray particle traveling along the path 40 but the second detector 20 does not obtain a result of detecting the cosmic ray particle, the control unit 32 determines that the cosmic ray particle failed to pass through the blast furnace 100 along the path 40. Cosmic ray particles that failed to pass through the blast furnace 100 along the path 40 are absorbed or scattered by a high-density material such as molten metal. The control unit 32 calculates the ratio of the number of cosmic ray particles traveling along the path 40 detected by the second detector 20 to the number of cosmic ray particles traveling along the path 40 detected by the first detector 10. The calculated ratio corresponds to the probability that a cosmic ray particle traveling along the path 40 will pass through the blast furnace 100.

[0046] When a cosmic ray particle is detected by the first detector 10, the control unit 32 may calculate and update the probability that the cosmic ray particle will pass through the blast furnace 100 based on whether the cosmic ray particle is also detected by the second detector 20 or not.

[0047] The control unit 32 may measure the state of the blast furnace 100 based on the probability that cosmic ray particles will pass through the blast furnace 100. For example, the control unit 32 may acquire in advance, as a first probability, the probability that cosmic ray particles will pass through the blast furnace 100 when the liquid level of the molten material has dropped to a state where the path 40 of the cosmic ray particles will not pass through the molten material. When the probability that cosmic ray particles will pass through the blast furnace 100 is equal to or greater than the first probability, the control unit 32 may determine that the liquid level of the molten material has dropped to a state where the path 40 of the cosmic ray particles will not pass through the molten material.

[0048] The control unit 32 may acquire in advance, as a second probability, the probability that a cosmic ray particle will pass through the blast furnace 100 when the liquid level of the molten material has risen to a state where a cosmic ray particle traveling along the path 40 will pass through the molten material for a predetermined distance. When the probability that a cosmic ray particle will pass through the blast furnace 100 is less than the second probability, the control unit 32 may determine that the liquid level of the molten material has risen to a state where a cosmic ray particle traveling along the path 40 will pass through the molten material for a predetermined distance.

[0049] When at least two (multiple) sets of first detectors 10 and second detectors 20 are installed outside the blast furnace 100, the control unit 32 may measure the smelt liquid level in the blast furnace 100 by determining the position of the smelt liquid level relative to the height at which each set of detectors is installed. Each set of the first detectors 10 and second detectors 20 may be installed such that the second detector 20 is located at a different height between the height of the tuyere 120 of the blast furnace 100 and the height of the taphole 130 of the blast furnace 100.

[0050] The control unit 32 measures changes in the state of the blast furnace 100 based on changes in the probability that cosmic ray particles will pass through the blast furnace 100. For example, the control unit 32 may determine that the liquid level in the blast furnace 100 tends to rise if the probability that cosmic ray particles will pass through the blast furnace 100 increases consecutively for a predetermined number of times or more. The control unit 32 may determine that the liquid level in the blast furnace 100 tends to fall if the probability that cosmic ray particles will pass through the blast furnace 100 decreases consecutively for a predetermined number of times or more. In other words, the control unit 32 may measure changes over time in the state of the measurement target part based on changes over time in the detection results of incoming particles and passing particles.

[0051] The control unit 32 may notify the user of the measurement results of the liquid level of the molten material in the blast furnace 100 or the measurement results of the change over time in the state of the measurement target part by displaying them on the display unit 34. The control unit 32 may cause the communication unit 36 ​​to transmit the measurement results to an external device.

[0052] As described above, in the measurement system 1 according to this embodiment, the measurement device 30 can measure the state inside the blast furnace 100 based on the detection results of cosmic ray particles arriving at the blast furnace 100. Here, the cosmic ray particles are particles that naturally arrive from outside the Earth. The number of cosmic ray particles that arrive at the blast furnace 100 is a constant amount over the long term.

[0053] Therefore, as a comparative example, it is possible to consider a case where the number of cosmic ray particles arriving at the blast furnace 100 is assumed to be a constant amount, and only cosmic ray particles that have passed through the blast furnace 100 are detected. The device according to the comparative example is equipped with a detector that detects cosmic ray particles that have arrived from a predetermined direction and passed through the blast furnace 100. The device according to the comparative example obtains in advance a predicted value for the number of cosmic ray particles that will arrive from a predetermined direction within a predetermined period of time (e.g., 30 days). The device according to the comparative example obtains the number of cosmic ray particles that have actually been detected as cosmic ray particles that have passed through the blast furnace 100 within the predetermined period of time. The device according to the comparative example calculates the ratio of the number of cosmic ray particles that have actually been detected as cosmic ray particles that have passed through the blast furnace 100 to the predicted number of arriving cosmic ray particles, and measures the density of the molten material, etc. in the blast furnace 100 based on the calculation result.

[0054] However, the device according to the comparative example requires measurement over a long period of time so that the number of cosmic ray particles arriving at the blast furnace 100 is considered to be a constant amount. If the predetermined period is set to a short period of time, such as one hour, the number of cosmic ray particles that actually arrive at the blast furnace 100 during that period will vary. This results in a low correlation between the ratio of the number of cosmic ray particles actually detected as cosmic ray particles that have passed through the blast furnace 100 to the number of cosmic ray particles that arrive at the blast furnace 100 during the predetermined period and the actual density of the molten material, etc., inside the blast furnace 100. As a result, the device according to the comparative example cannot achieve at least one of shortening the measurement period and improving the measurement accuracy of the density of the molten material, etc., inside the blast furnace 100.

[0055] On the other hand, the measurement system 1 according to this embodiment can measure the conditions inside the blast furnace 100 with high accuracy even in a short period of measurement by determining whether a cosmic ray particle has passed through the blast furnace 100 each time the cosmic ray particle arrives at the blast furnace 100.

[0056] <40° angle of the cosmic ray particle path to be detected> In nature, cosmic ray particles that reach the Earth are absorbed or scattered by the Earth and the atmosphere. Cosmic ray particles that arrive from directions close to the horizontal are more likely to be absorbed or scattered in the atmosphere due to the long distance they pass through the atmosphere, making it difficult for them to reach the ground. Cosmic ray particles that arrive from underground are more likely to be absorbed by the Earth as they pass through the Earth, making it difficult for them to reach the ground on the other side. On the other hand, cosmic ray particles that arrive from the zenith direction are more likely to reach the ground than cosmic ray particles that arrive from the horizontal direction due to the shorter distance they pass through the atmosphere. Therefore, the number of cosmic ray particles that reach the ground where the blast furnace 100 is installed is greater for those that arrive from directions closer to the zenith.

[0057] In the measurement system 1 according to this embodiment, the detector, which is a combination of the first detector 10 and the second detector 20, is positioned side by side on a path 40 with the blast furnace 100 in between. The first detector 10 and the second detector 20 are positioned according to the angle θ that the direction in which the path 40 extends forms with respect to the horizontal direction. In other words, the first detector 10 and the second detector 20 are positioned on both sides of the portion to be measured on a straight line that passes through the portion to be measured in the blast furnace 100.

[0058] When the measuring device 30 measures the liquid level of the molten material in the blast furnace 100, the first detector 10 and the second detector 20 are positioned so that the difference between the number of cosmic ray particles detected when the liquid level is high and the number of cosmic ray particles detected when the liquid level is low is large, thereby improving the accuracy of detecting the liquid level.

[0059] Therefore, the setting value of the angle θ that the path 40 makes with respect to the horizontal direction was changed, and the relationship between the number of cosmic ray particles passing through the blast furnace 100 detected by the second detector 20 when the first detector 10 and the second detector 20 were positioned based on each setting value of the angle θ was confirmed by calculation. As a result, the relationship shown in the graph of FIG. 4 was obtained. The horizontal axis of the graph in FIG. 4 represents the angle of the path 40. The vertical axis represents the detection value of the second detector 20. The detection value of the second detector 20 corresponds to the number of cosmic ray particles detected by the second detector 20. As a premise for the calculation, the number of cosmic ray particles traveling along the path 40, i.e., the number of cosmic ray particles detected by the first detector 10, was assumed to be constant.

[0060] The solid line graph represented by L1 represents the detection value of the second detector 20 obtained when the liquid level of the molten material in the blast furnace 100 is low (when the liquid level is close to the height of the taphole 130). The dashed dotted line graph represented by L2 represents the detection value of the second detector 20 obtained when the liquid level of the molten material in the blast furnace 100 is high (when the liquid level is close to the height of the tuyere 120). The higher the liquid level of the molten material, the more difficult it is for cosmic ray particles to pass through, and therefore the detection value of the second detector 20 becomes smaller.

[0061] The control unit 32 of the measurement device 30 calculates an integrated value of the density of a substance, such as a molten material, present on the path 40 based on the detection value of the second detector 20. The control unit 32 determines the position of the molten material's liquid level based on the difference between the integrated values ​​of density. Therefore, the greater the difference between the detection values ​​of L1 and L2, the more accurately the position of the molten material's liquid level can be measured. In the graph of FIG. 4, when the angle θ is set within the range indicated by R, the difference between the detection values ​​of L1 and L2 is equal to or greater than a predetermined value. Therefore, by setting the angle θ to a value within the range indicated by R, the accuracy of determining the molten material's liquid level can be improved.

[0062] 4, the range indicated by R is the range from 40 degrees to 60 degrees. In other words, by setting the path 40 in a direction that forms an angle between 40 degrees and 60 degrees with respect to the horizontal direction and arranging the first detector 10 and the second detector 20 on the path 40, the accuracy of determining the liquid level of the molten material can be improved.

[0063] <Measurement based on the energy of cosmic ray particles> As an example, the first detector 10 and the second detector 20 are each configured to be able to detect the energy of cosmic ray particles. The second detector 20 may have one or more pairs of detectors each combining a first panel 11 and a second panel 12. The time and coordinates when a particle passing through the second detector 20 passes through the first pair of panels and the second pair of panels, respectively, may be recorded. The time it takes to travel between the two pairs of panels may be calculated from the recorded times. The distance traveled between the two pairs of panels may be calculated from the coordinates. The velocity of the muon particle may be calculated by dividing the distance traveled by the time obtained from these records. Because the mass of the muon particle is constant, the kinetic energy may be calculated by multiplying the square of the velocity by the mass of the muon particle and dividing the result by 2.

[0064] The control unit 32 of the measurement device 30 may measure the state inside the blast furnace 100 based not only on the number of detected cosmic ray particles but also on the detection results of the energy of the cosmic ray particles. For example, the control unit 32 may measure the liquid level of the molten material in the blast furnace 100 based on the detected value of cosmic ray particles whose energy value is within a predetermined range. When the measurement device 30 measures the liquid level of the molten material in the blast furnace 100, the accuracy of liquid level detection can be improved by detecting cosmic ray particles so that the difference between the number of detected cosmic ray particles when the liquid level is high and the number of detected cosmic ray particles when the liquid level is low is large.

[0065] The difference between the number of cosmic ray particles detected when the molten material level is high and the number of cosmic ray particles detected when the molten material level is low varies depending on the energy of the cosmic ray particles, as shown in the graph of FIG. 5. The horizontal axis of the graph in FIG. 5 represents the energy of the cosmic ray particles. The vertical axis represents the difference between the detection value by the second detector 20 of cosmic ray particles passing through the blast furnace 100 when the molten material level is low and the detection value by the second detector 20 of cosmic ray particles passing through the blast furnace 100 when the molten material level is high. As a premise, the number of cosmic ray particles traveling along path 40, i.e., the number of cosmic ray particles detected by the first detector 10, is assumed to be constant. The vertical axis is normalized so that the maximum value is represented as 1. The horizontal axis is also normalized so that the energy at which the difference between the detection value when the molten material level is low and the detection value when the molten material level is high is represented as 1.

[0066] 5, there is an energy range in which the difference between the number of cosmic ray particles detected when the molten material level is high and the number of cosmic ray particles detected when the molten material level is low becomes large. The control unit 32 may calculate the molten material level in the blast furnace 100 based on the results of detecting cosmic ray particles within that energy range. By limiting the energy range of cosmic ray particles to be detected, the accuracy of calculating the molten material level can be improved.

[0067] The control unit 32 may acquire, from the first detector 10 or the second detector 20, information on the detection of cosmic ray particles and a measurement value of the energy of the detected cosmic ray particles. The control unit 32 may reflect only information on the detection of cosmic ray particles that falls within an energy range in which the difference between the number of cosmic ray particles detected when the molten liquid level is high and the number of cosmic ray particles detected when the molten liquid level is low, in the calculation of the liquid level of the molten material in the blast furnace 100. The control unit 32 may not reflect information on the detection of cosmic ray particles that falls outside of an energy range in which the difference between the number of cosmic ray particles detected when the molten liquid level is high and the number of cosmic ray particles detected when the molten liquid level is low, in the calculation of the liquid level of the molten material in the blast furnace 100.

[0068] The measurement system 1 may further include a deflector that applies a magnetic field to cosmic ray particles before they enter the first detector 10 to deflect the trajectory of the cosmic ray particles. The deflector may be configured to selectively allow only cosmic ray particles having energies within a predetermined energy range to enter the first detector 10. The deflector may be included in the first detector 10. The accuracy of calculating the melt level can also be improved by limiting the energies of the cosmic ray particles that enter the first detector 10 and the second detector 20 using the deflector. In other words, the control unit 32 may measure the change over time in the density of the material present in the measurement target portion based on the change over time in the number of cosmic ray particles having a predetermined energy that pass through the measurement target portion.

[0069] <Example of measuring the liquid level of a molten material> As an example, a measurement example will be described in which the direction in which the cosmic ray particles to be detected are coming (the direction of path 40) is at an elevation angle of 40 degrees with respect to the horizontal. The first detector 10 and the second detector 20 are installed along the path 40. The first detector 10 is located on the side of the blast furnace 100 in the direction in which the cosmic ray particles are coming (before the cosmic ray particles enter the blast furnace 100). The second detector 20 is located on the side of the blast furnace 100 in the direction in which the cosmic ray particles are passing through the blast furnace 100. Six combinations of these first and second detectors were installed.

[0070] The control unit 32 of the measurement device 30 acquires the detection results of cosmic ray particles from each of the first detector 10 and the second detector 20. The control unit 32 calculates the ratio of the detection value of cosmic ray particles (the number of detected cosmic ray particles) by the second detector 20 to the detection value of cosmic ray particles (the number of detected cosmic ray particles) by the first detector 10. The control unit 32 measures the liquid level of the molten material in the blast furnace 100 based on the calculated ratio.

[0071] As illustrated in the graph of FIG. 6, there is a correlation between the ratio of the detected values ​​and the molten liquid level. The horizontal axis of the graph in FIG. 6 represents the ratio of the detected values. The vertical axis represents the molten liquid level. The molten liquid level is expressed as a dimensionless value normalized by setting the height of the taphole 130 to 0 and the height of the tuyere 120 to 1. When the molten liquid level is known, the ratio of the actual detected values ​​of the first detector 10 and the second detector 20 varies with each liquid level, but shows high linearity with respect to the molten liquid level.

[0072] According to the graph in Figure 6, when calculating the normalized liquid level value from the ratio of actual detection values, if the standard deviation (σ value) of the normalized liquid level value falls within about 0.04, even taking into account the detection errors of the first detector 10 and the second detector 20, it is possible to determine with high accuracy whether the liquid level has risen to the height of the tuyere 120, whether the liquid level has fallen to the height of the tap hole 130, or whether the liquid level is between the height of the tuyere 120 and the height of the tap hole 130.

[0073] <Comparison with comparative examples> In the embodiments described above, the control unit 32 does not limit the energy range of cosmic ray particles to be detected. Hereinafter, an embodiment in which changes in the liquid level of the melt are measured without limiting the energy range of cosmic ray particles will be referred to as embodiment 1. The control unit 32 may limit the energy range of cosmic ray particles to be detected. An embodiment in which changes in the liquid level of the melt are measured while limiting the energy range of cosmic ray particles will be referred to as embodiment 2.

[0074] On the other hand, as a comparative example, an apparatus is assumed that measures changes in the liquid level of the molten material based only on the detection results of cosmic ray particles that have passed through the blast furnace 100 without using base data.

[0075] The results of measuring changes in the liquid level of the molten material in Examples 1 and 2, and the comparative example, are shown in Table 1 below. The measurement system 1 according to Example 1 includes a first detector 10 and a second detector 20, and is shown to not limit the energy range of cosmic ray particles used for measurement. The measurement system 1 according to Example 2 includes a first detector 10 and a second detector 20, and is shown to be a system that limits the energy range of cosmic ray particles used for measurement. The device according to the comparative example is shown to be a device that does not refer to base data, does not limit the energy range of cosmic ray particles used for measurement, and measures the liquid level of the molten material based only on the detection results of cosmic ray particles that have passed through the blast furnace 100. [Table 1]

[0076] The variation in the measured values ​​of the liquid level of the molten material in the blast furnace 100 using the measurement systems 1 of Examples 1 and 2 and the apparatus of the comparative example was calculated as the average value of the difference between adjacent measurements divided by the standard deviation (σ). The larger this value, the greater the difference between the measurements is compared to the variation, indicating that the difference can be detected more significantly. Here, the measured liquid level is calculated as a dimensionless value normalized by setting the height of the taphole 130 to 0 and the height of the tuyere 120 to 1. Both examples using the measurement systems 1 of Examples 1 and 2 showed values ​​superior to those of the comparative example, indicating that fluctuations in the measurement data due to changes in the liquid level can be easily detected. Table 1 confirms that the measurement system 1 of this embodiment can measure the liquid level of the molten material in the blast furnace 100 with higher accuracy than the apparatus of the comparative example.

[0077] <Example of procedure for measuring the condition of a blast furnace 100> In the measurement system 1 according to this embodiment, an example of the procedure of the method for measuring the state of the blast furnace 100 executed by the control unit 32 of the measurement device 30 will be described based on the procedure of the flowchart illustrated in Fig. 7. The method for measuring the state of the blast furnace 100 may be realized as a state measurement program executed by a processor constituting the control unit 32. The state measurement program may be stored on a non-transitory computer-readable medium.

[0078] The control unit 32 acquires the detection results of cosmic ray particles arriving at the blast furnace 100 from the first detector 10 and the second detector 20 (step S1). The control unit 32 calculates the rate at which the cosmic ray particles pass through the blast furnace 100 (step S2).

[0079] The control unit 32 determines whether the rate at which cosmic ray particles pass through the blast furnace 100 has changed by more than a predetermined value (step S3). If the rate at which cosmic ray particles pass through the blast furnace 100 has changed by more than a predetermined value (step S3: YES), the control unit 32 detects that the state inside the blast furnace 100 has changed (step S4). After executing the procedure of step S4, the control unit 32 ends execution of the procedure of the flowchart in Fig. 7. If the rate at which cosmic ray particles pass through the blast furnace 100 has not changed by more than a predetermined value (step S3: NO), the control unit 32 ends execution of the procedure of the flowchart in Fig. 7.

[0080] The control unit 32 may compare the ratio calculated in step S2 of the example procedure in the flowchart of Figure 7 with a predetermined threshold value such as the first probability or the second probability in step S3, and measure the liquid level of the molten material in the blast furnace 100 in step S4.

[0081] (summary) As described above, in the measurement system 1 according to this embodiment, the control unit 32 of the measurement device 30 can measure changes in the state inside the blast furnace 100 over time based on the detection results of the first detector 10 and the second detector 20 installed on either side of the blast furnace 100. In this way, changes in the state inside the blast furnace 100 can be measured over time based on short-term measurements, without having to measure the number of incoming cosmic ray particles over a long period of time. As a result, the state inside the blast furnace 100 can be measured so as to follow those changes.

[0082] Although the embodiments of the present disclosure have been described based on the drawings and examples, it should be noted that those skilled in the art could make various modifications or alterations based on the present disclosure. Therefore, it should be noted that these modifications and alterations are included within the scope of the present disclosure. For example, the functions included in each component or step can be rearranged so as not to cause logical inconsistencies, and multiple components or steps can be combined or divided into one. The embodiments of the present disclosure can also be realized as a program executed by a processor included in an apparatus or a storage medium on which a program is recorded. It should be understood that these are also included within the scope of the present disclosure. [Explanation of symbols]

[0083] 1. Measurement System 10 First detector (11: First panel, 12: Second panel, 15: Light-emitting cell) 20 Second detector 30 Measuring device (32: control unit, 34: display unit, 36: communication unit) 40, 41, 42 Paths of cosmic ray particles 100 Blast furnace (110: furnace body, 120: tuyere, 130: tap hole, 140: raw material, 150: slag, 160: pig iron)

Claims

1. A first detector and a second detector are arranged on both sides of the measurement target portion on a path passing through the measurement target portion in the blast furnace, and a measurement device is provided, the first detector detects, as incoming particles, cosmic ray particles that have arrived along the path and before they are incident on the measurement target portion; the second detector detects the incoming particles that have passed through the measurement target portion as passing particles; The measuring device is measuring a change over time in the state of the measurement target portion based on a change over time in the detection results of the incoming particles and the passing particles; Condition measurement system inside a blast furnace.

2. 2. The system for measuring a state inside a blast furnace according to claim 1, wherein the measuring device measures a change over time in the density of a substance present in the measurement target portion based on a change in the number of cosmic ray particles detected as the incoming particles by the first detector and also detected as the passing particles by the second detector.

3. The measuring device is calculating a change over time in the rate at which cosmic ray particles pass through the measurement target portion based on a change in the number of cosmic ray particles detected as the incoming particles by the first detector and also detected as the passing particles by the second detector; The system for measuring a state inside a blast furnace according to claim 2 , wherein a change over time in density of the material present in the measurement target portion is measured based on the change over time in the calculated ratio.

4. the first detector or the second detector measures the energy of the incoming cosmic ray particle; 4. The system for measuring a state inside a blast furnace according to claim 2 or 3, wherein the measurement device measures a change over time in the density of a substance present in the measurement target portion based on a change over time in the number of cosmic ray particles having a predetermined energy that pass through the measurement target portion.

5. 4. The system for measuring a state inside a blast furnace according to claim 1, further comprising a deflector that deflects the trajectory of cosmic ray particles having energies outside a predetermined range among the cosmic ray particles that have arrived along the path.

6. 4. The system for measuring a state inside a blast furnace according to claim 1, wherein the first detector and the second detector are installed so as to detect cosmic ray particles coming from an elevation angle in the range of 40 degrees or more and 60 degrees or less.

7. At least two pairs of the first detector and the second detector are provided; 4. The system for measuring a condition inside a blast furnace according to claim 1, wherein each set of the first detector and the second detector is installed so that the second detector is positioned at a different height between the height of the tuyere of the blast furnace and the height of the tap hole of the blast furnace.

8. detecting incoming particles that are cosmic ray particles traveling along a path passing through a measurement target portion in a blast furnace and before being incident on the measurement target portion; detecting passing particles that are the particles that have passed through the measurement target portion; measuring a change over time in the state of the measurement target portion based on a change over time in the detection results of the incoming particles and the passing particles; A method for measuring conditions inside a blast furnace, including:

Images