JP5222812B2 - Hot spot radiation measuring method and apparatus - Google Patents

Description

  The present invention relates to a top blowing method in which the component (composition) of the hot metal is adjusted to the target component (composition) by spraying oxygen through a lance to the hot metal contained in a converter or a pan in a steel factory. More particularly, the present invention relates to a hot spot radiation measuring method and a hot spot radiation measuring apparatus for measuring radiation emitted from a fire spot generated below an acid feed hole at the lower end of a lance.

  The converter uses pig iron (hot metal) supplied from the blast furnace and scraps separately prepared as a main raw material. After adding auxiliary materials such as lime to this, oxygen is blown from above through a lance, A function that removes substances other than iron such as silicon Si and carbon C contained in steel by oxidation, refines steel with the target component (composition) and temperature, and supplies it to the next casting process. Have. Moreover, the pan is performing the preliminary process with respect to the hot metal supplied to a converter.

In the actual operation (operation) of the converter and pan having such functions, the hot metal by intermittent sampling of the hot metal during the blowing process (process) for the hot metal contained in the converter and pan It is possible to measure components and temperature.

  However, since it is difficult to continuously monitor the hot metal components during blowing with oxygen, the hot metal components, temperature, hot metal amount, etc. before the start of blowing, the amount of acid sent from the lance, the position of the lance, Calculate and estimate the hot metal component being blown from the acid time, etc., control the operation so that the hot metal component at the end of the operation becomes a predetermined target component, and when it is determined that the predetermined target component has been reached Blowing has ended.

  For this reason, the actual hot metal component varies with respect to the estimated hot metal component at the end of blowing, and it does not necessarily become the assumed target component, but additional blowing is performed, component adjustment, or processing in the next process An increase in load occurs, resulting in an increase in operating hours and operating costs.

  On the other hand, an attempt to appropriately control the operation by continuously measuring hot metal components and the like during the blowing operation online has been proposed.

  As a method for directly measuring the components of hot metal in containers such as converters and pans online, Patent Document 1 irradiates the hot metal (molten metal) with a laser beam or the like and performs spectroscopic analysis of the emitted light. A technique for measuring the hot metal component by performing it has been proposed.

Further, in Patent Document 2, light emission (radiated light) from a fire point generated below (front) the acid lance is not spectrally analyzed, but the hot metal component is estimated based on the analysis result. A method to do this has been proposed.

  Further, Patent Document 3 proposes a method of measuring the molten metal temperature online by measuring the radiated light from the molten iron itself via a lance, a furnace body (furnace bottom, etc.) nozzle, or the like.

JP 58-102137 A JP-A-62-67430 JP-A-62-226025

  However, the following problems still need to be improved in each method for directly or indirectly measuring the components of the hot metal contained in a vessel such as a converter or a pan on-line.

  That is, in the spectroscopic analysis method of fire point radiation light described in Patent Document 2, an optical fiber is inserted into the lance, and light emission from the fire point generated below (front) the lance incident from the tip of the lance. (Radiated light) is detected and propagated to a spectroscopic analyzer outside the furnace to perform spectroscopic analysis of the detected light.

  However, the level of incident light from the tip of the lance varies greatly due to disturbance factors such as slag, metal adhesion, and generation of fumes (smoke) at the lance tip. It is difficult to perform measurement and analysis. In particular, when the incident light fluctuates due to such disturbance factors, it is possible to determine whether this fluctuation is a light fluctuation due to a change in the actual blowing state or hot metal state or a fluctuation due to disturbance. Since it is not possible, it may be an erroneous measurement.

  In addition, accurate component analysis of the hot metal also requires information such as the exact temperature of the hot metal, and if the level fluctuation of the incident light is large, it will be accurate continuously during operation (operation). It is difficult to perform a simple component analysis.

  Furthermore, in the spectroscopic analysis method of the fire point radiation light described in Patent Document 2, since it is necessary to install and lay an optical fiber in the lance, the structure of the lance becomes complicated, and the lance is installed in the facility. There is a concern that integration will become complicated and maintenance management will become complicated. The method described in Patent Document 1 has the same problem.

  Furthermore, even in the method of measuring the radiation light from the hot metal via the lance or furnace body nozzle described in Patent Document 3 and measuring (calculating) the temperature, the same problem and the variation in the effective emissivity of the hot metal Since the temperature fluctuates, there is a problem that it is difficult to measure the exact temperature of the hot metal.

  The present invention has been made in view of such circumstances, and even if the level of incident light from the acid feed hole at the tip of the lance fluctuates greatly due to disturbance factors, it is accommodated in a container such as a converter or a pan. It is possible to accurately detect changes in hot metal components online, estimate the progress of blowing processes such as desiliconization and decarburization reactions, start and end of desiliconization and decarburization reactions, and change in reaction rate It is an object of the present invention to provide a hot spot radiation measuring method and a hot spot radiation measuring apparatus capable of accurately detecting arrival, passage, etc. of a specific condition such as the above.

  In order to solve the above-mentioned problem, the hot spot radiation measuring method of the present invention is a top blowing method, where a portion including an acid feed hole at the lower end of a lance for feeding acid is photographed through the lance and photographed. From the brightness distribution of the image, obtain the radiant brightness of the radiant light emitted from the fire point generated at the bottom of the lance at the bottom of the lance, and calculate the hot metal from the relative temporal change in the calculated moving average value of the radiated light intensity. The change of the component is detected.

First, in the hot spot radiation measuring method configured as described above, the radiant brightness of the radiated light emitted from the fire point generated below the acid feed hole at the lower end of the lance is obtained, and the moving average value of the radiated light brightness is calculated. The operation principle that can detect the change of the hot metal component from the relative time change amount will be described.

  The emitted light of the hot spot is emitted with combustion and heat generation such as desiliconization and decarburization reaction caused by oxidation of oxygen supplied from the lance, and the radiant brightness is the result of desiliconization and decarburization at the hot spot. Varies depending on reaction conditions.

  The radiant brightness from the hot spot varies depending on the state of the hot metal, molten steel (temperature, weight, etc.) and the conditions of acid delivery from the lance, but the temporal change of the radiant brightness, that is, the temporal transition of the radiant intensity. Pattern change (change from a constant radiant brightness at the start of blowing to a state where the brightness decreases or increases during the blowing process, or from a decrease or increase at the end of blowing to a constant radiant brightness state Etc.) is determined mainly by the reaction efficiency at the hot spot.

  Therefore, it is possible to estimate the progress of the blowing process by measuring the radiant brightness of the synchrotron radiation and detecting its relative change over time, or reaching the specific conditions of the blowing process. Alternatively, it is possible to detect passage (start, end, change in reaction rate, etc. of desiliconization, decarburization reaction, etc.).

For example, in the hot metal decarburization treatment, oxygen in the hot metal is blown onto the hot metal to cause the carbon in the hot metal to react with the supplied oxygen to produce CO and CO ₂ , thereby decarburizing the hot metal. At this time, when the carbon concentration in the hot metal is high, if the amount of acid sent through the lance is constant, the decarburization reaction amount is almost constant, and the carbon concentration in the hot metal is considered to decrease at a constant rate. However, when the carbon concentration in the hot metal decreases, the reaction efficiency decreases even when a certain amount of acid is fed, and the amount of decarburization reaction decreases.

  At this time, as the carbon concentration in the hot metal decreases and the amount of decarburization reaction decreases as the blowing progresses, the amount of heat generated along with the decarburization reaction also decreases, and the radiance of the hot spot decreases. It is considered that the progress of decarburization reaction can be estimated by observing the relative change in the hot spot radiance.

  As described above, in the present invention, the change in the hot metal component is detected from the relative temporal change amount of the radiant brightness of the hot spot rather than the spectral analysis result at each time point of the radiant brightness of the hot spot. Therefore, even if the level of incident light from the tip of the lance fluctuates greatly due to disturbance factors, it is possible to accurately detect on-line changes in hot metal components contained in a vessel such as a converter or a pan.

  Further, in the present invention, a portion including the acid feeding hole at the lower end of the lance is photographed through the lance, and the emission of a fire point generated below the acid feeding hole at the lower end of the lance is generated from the luminance distribution of the photographed image. The radiant brightness of light is being sought. Therefore, even if the position of the oxygen feed hole in the image taken due to disturbance factors such as slag, metal adhesion, or fume (smoke) generation at the bottom of the lance is shifted, The radiant light brightness of the radiant light emitted from the generated fire point can be obtained more accurately.

  According to another invention, in the above-described hot spot radiation measuring method of the invention, an opening is provided at the upper end portion of the lance so that the acid feeding hole at the lower end of the lance can be directly observed. The part including the hole is photographed.

  In the fire point radiation measuring method configured in this way, the portion including the acid feed hole at the lower end of the lance is photographed from the upper end of the lance through the inner side of the lance. Integration into the system is simplified, and maintenance management work is simplified.

According to another invention, in the above-described hot spot radiation measurement method of the invention, a portion corresponding to an acid feed hole in an image is extracted from the luminance distribution of a photographed image, and the maximum brightness of the portion corresponding to the acid feed hole or The average luminance is obtained as the representative luminance of the portion corresponding to the acid feed hole, and the obtained representative luminance is set as the radiant light luminance of the radiated light emitted from the fire point.

  In the fire point radiation measuring method configured in this way, the position of the oxydation hole at the tip of the lance and the imaging due to the displacement of the imaging position and imaging direction due to disturbance, vibration, etc., or deformation due to the deflection of the lance itself, etc. Even when the position relative to the position changes and the position of the acid feed hole in the photographed image fluctuates, the portion corresponding to the acid feed hole can be accurately determined. Furthermore, since the radiant brightness of the emitted light emitted from the fire point is the maximum brightness or average brightness of the portion corresponding to the acid feed hole, the brightness of the emitted light emitted from the fire point can be obtained more accurately and stably. it can.

According to another aspect of the present invention, there is provided a method for calculating a maximum luminance or an average luminance of a representative luminance in accordance with an area of a portion corresponding to an acid feed hole in an extracted image in the method for measuring a hot spot radiation of the above invention. Yes.

  The actual area of the acid feed hole changes due to factors such as the occurrence of slag and metal adhesion at the bottom of the lance, and the acid feed hole determined by, for example, binarization processing from the luminance distribution of the photographed image The area of the portion corresponding to changes.

  Therefore, in the hot spot radiation measuring method of the present invention, for example, when the area is small, the radiance of the fire point obtained is low, so the maximum brightness is adopted as the representative brightness, and when the area is large, the fire point radiation obtained is Since the luminance is high, the average luminance is adopted as the representative luminance. Therefore, it is possible to stably measure the hot spot radiance incident from the acid feed hole regardless of the state of the acid feed hole.

  Still another invention is the above-described fire point radiation measuring method according to the invention, wherein the portion including the acid feeding hole at the lower end of the lance is photographed by the camera through the lance, and the light incident on the camera from the portion including the acid feeding hole is provided. The brightness is adjusted so that the brightness of the camera falls within the sensitivity range of the camera.

The brightness of radiant light incident from the acid hole at the lower end of the lance varies greatly depending on the reaction state at the hot spot. Therefore, in the hot spot radiation measuring method configured as described above, the brightness adjustment is performed so that the brightness of light incident on the camera from the portion including the acid feed hole falls within the sensitivity range of the camera. Even in the case of extreme fluctuations, it is possible to prevent accurate measurement and discrimination from being performed due to saturation or the like of the portion including the acid feed hole in the image (radiated light from the fire point).

  In another aspect of the present invention, a fire point radiation measuring apparatus is set at the upper end opening of a lance installed to feed acid from above into a container containing at least hot metal, and images a portion including an acid feeding hole at the lower end of the lance. A change in the component of the hot metal based on the time change of the calculated brightness of the acid feeding hole, and an image processing means for calculating the brightness of the acid feeding hole in the image taken by the photographing means. Signal processing means for detecting.

  In the hot spot radiation measuring method and the hot spot radiation measuring apparatus of the present invention, the portion including the acid feed hole at the lower end of the lance is photographed through the lance, and the radiation emitted from the fire spot from the luminance distribution of the photographed image. The light intensity is obtained, and the change of the hot metal component is detected from the time change of the obtained radiant light intensity.

  Therefore, even if the level of incident light from the lower end of the lance fluctuates greatly due to disturbance factors such as slag, metal adhesion, and generation of fumes (smoke) in the acid feed hole at the lower end of the lance, It is possible to accurately detect changes in hot metal components contained in containers such as on-line, estimate the progress of blowing processes such as desiliconization and decarburization reactions, and start and end of desiliconization and decarburization reactions. In addition, it is possible to accurately detect the arrival or passage of a specific condition such as a change in reaction rate.

Schematic diagram of a converter using a blowing process to which a hot spot radiation measuring method and a hot spot radiation measuring apparatus according to an embodiment of the present invention are applied. The figure which shows the structure of the lance of the converter to which the hot spot radiation measuring method of the embodiment is applied The figure which shows the characteristic of the CMOS-CCD camera employ | adopted with the hot spot radiation measuring method of the embodiment The figure which shows the image image | photographed with the CMOS-CCD camera The figure for demonstrating the principle of operation of the hot spot radiation measuring method of the embodiment Flow chart showing the operation of the hot spot radiation measurement method of the same embodiment Similarly, a flowchart showing the operation of the hot spot radiation measurement method of the same embodiment The figure which shows the brightness | luminance characteristic (time characteristic) of the synchrotron radiation measured with the hot spot radiation measuring method of the embodiment

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a schematic view of a converter using a blowing process to which a hot spot radiation measuring method and a hot spot radiation measuring apparatus according to an embodiment of the present invention are applied.

  A hot metal 2 is accommodated in a furnace body 1 having an upper end opening of a converter as a container. A lance 3 having a length of about 7 m is provided above the furnace body 1. As shown in the schematic cross-sectional view of FIG. 2, the lance 3 includes an inner tube 3a having a diameter of about 50 mm through which oxygen 8 flows and an outer tube 3b through which cooling water 10 surrounding the inner tube 3a flows. The lance 3 is formed with four 10 mm-diameter acid feed holes 4 a, 4 b, 4 c, and 4 at the lower end of the lance 3. In this specification, the four acid feed holes 4a, 4b, 4c, and 4d are collectively referred to as an acid feed hole 4.

  A fire point 5 is formed below the acid feed hole 4 at the lower end of the lance 3. A branch pipe 6 is attached to the upper end of the lance 3, and an oxygen hose 7 for supplying oxygen 8 is connected to one of the branch pipes 6. In addition, a pair of cooling water hoses 9 and 11 for allowing the cooling water 10 to flow through the outer pipe 3 a are connected near the upper end of the lance 3.

  A measurement case 13 is attached to the other side of the branch pipe 6, and an opening 12 is formed in the bottom wall of the measurement case 13 so that the acid feed hole 4 at the lower end of the lance 3 can be directly seen. A monochrome CMOS-CCD camera 15 is attached via a lens 14 at a position facing the opening 12 of the measurement case 13. The CMOS-CCD camera 15 photographs a portion including the acid feed hole 4 at the lower end of the lance 3 from the inside of the lance 3 through the lens 14 and the opening 12, and the photographed two-dimensional image is transmitted through the communication cable 16. Then, the data is sent to the signal processing device 17 composed of an information processing device such as a computer.

  Note that a protective glass for protecting the lens 14 and the CMOS-CCD camera 15 from an external adverse environment is incorporated in the opening 12 of the measurement case 13. This protective glass is air purged as necessary.

  The lens 14 has a function of enlarging an image of a portion including the acid feed hole 4 at the lower end of the lance 3 and entering the image into the CMOS-CCD camera 15. Specifically, a CMOS-CCD camera 15 in which a lens 14 with a focal length of 300 mm is attached to a lance 3 having a lance length of about 7 m and an inner tube diameter of 50 mm is employed. A field of view equivalent to 200 × 250 mm is photographed with the CMOS-CCD camera 15 at the position of the tip of the lance. Then, the CMOS-CCD camera 15 is positioned via the lens 14 so that the center position of the four acid feed holes 4a to 4d at the lower end of the lance 3 is located at the center of the photographed image.

  In the case of the embodiment, each of the feed holes 4a to 4d in the image of the portion including the feed hole 4 at the lower end of the lance 3 photographed by the CMOS-CCD camera 15 has a size of 1/15 or less with respect to the entire image. However, the shape and state of each of the acid feed holes 4a to 4d on the image can be discriminated, and the size is satisfactory for measurement processing.

  Although it is possible to increase the focal length of the lens 14 used for photographing and enlarge the size of each of the acid feed holes 4a to 4d on the image, in the actual operation (operation) of the converter, the vibration accompanying the operation. The relative position of the acid feed hole 4 with respect to the CMOS-CCD camera 15 may be displaced due to the bending (bending) of the lance 3 itself due to, for example, the CMOS-CCD because the acid feed hole 4 may be out of the image field of view. The visual field range of the camera 15 is set wide.

  In the embodiment, a CMOS-CCD camera 15 is installed in the opening 12 provided in the bottom wall of the measurement case 13 at the upper end of the lance 3 via the lens 14, and the acid-feeding at the lower end of the lance 3 is performed by the CMOS-CCD camera 15. The part including the hole 4 was photographed. However, if the size of the CMOS-CCD camera 15 is such that there is no problem in sending oxygen to the inner tube 3a of the lance 3, the CMOS-CCD camera 15 is inserted into the lance 3 for photographing. Is also possible.

Furthermore, it is also possible to insert a transmission optical system composed of a lens and an optical fiber into the lance 3 and connect it to a CMOS-CCD camera outside the lance 3, and take a picture with this CMOS-CCD camera. Further, an opening 12 is directly formed at the upper end of the lance 3, and only a transmission optical system composed of a lens and an optical fiber is attached to the opening 12, and this CMOS-CCD is connected to a CMOS-CCD camera installed at a remote position. It is also possible to take a picture with a camera.

In the embodiment, a CMOS-CCD camera 15 having a wider dynamic range than a normal CCD camera is used as a camera for photographing a portion including the acid feed hole 4 at the lower end of the lance 3. As shown in FIG. 3, the conventional CCD camera has a linear relationship between the incident luminance with respect to the camera and the luminance in the captured image, whereas the CMOS-CCD sensor 15 has a high luminance incident or a low luminance incident. The conversion characteristic to luminance on the image has a gradual characteristic. As described above, since the CMOS-CCD camera 15 has a wide photographic possible luminance range, even when high-intensity light is incident or fluctuates, particularly in the case of fired light, saturation does not occur on the image, and incident light It is possible to measure the brightness.

  In the embodiment, the CMOS-CCD camera 15 is employed as a camera for photographing the portion including the acid feed hole 4 at the lower end of the lance 3. However, in the conventional combination of the CCD camera and the lens, an automatic adjustment mechanism of the lens diaphragm In addition, the shutter speed control mechanism is provided to adjust the incident luminance level to the camera and the camera sensitivity, and the incident light luminance is calculated from the adjustment amount of the captured image and the adjustment mechanism. It is also possible to correspond to the incident light range.

FIG. 4 shows a portion including the oxygen feed hole 4 at the lower end of the lance 3 photographed by the CMOS-CCD camera 15 during the blowing operation in which the oxygen 8 is sprayed onto the hot metal 2 accommodated in the furnace body 1 using the lance 3. The image of is shown. On the image, the acid sending hole 4 part is a high luminance region because the emitted light from the fire point 5 generated by the acid sending is incident. The CMOS-CCD camera 15 continuously shoots the portion including the acid feeding hole 4 at the lower end of the lance 3, and signals the image of the portion including the acid feeding hole 4 at the lower end of the lance 3 as an image (video) signal. It is sent to the processing device 17.

In the converter having such a configuration, it is assumed that silicon Si contained in the hot metal 2 stored in the furnace body 1 is oxidized and removed with oxygen 8 supplied from the lance 3. In this case, FIG. 5A shows an example of the relationship between the supply time t of oxygen 8 from the lance 3, the component ratio (concentration) of silicon Si, and the radiant brightness S of the radiated light emitted from the fire point 5.

  That is, before the start of blowing, no hot spot is generated in front (downward) of the lance, but since hot hot metal exists in front of the lance, emitted light from the hot metal is observed.

When blowing (acid feeding) is started, a fire point is generated by oxygen blown from the lance to the hot metal, and radiant light is generated by the desiliconization reaction at the hot spot part, so that the radiant brightness rapidly increases immediately after the start of blowing. To rise. Thereafter, as the desiliconization reaction proceeds, the radiant light brightness gradually increases. As the blowing progresses, the silicon component ratio in the hot metal decreases, and if the ratio becomes below a certain value, the rate of increase in radiant brightness increases.

As blowing progresses and desiliconization proceeds further, the radiant brightness increases further. However, when the silicon removal ratio ends and the silicon component ratio in the hot metal reaches a small value, the radiant intensity is almost constant. The value comes to show.

  The arrival of a specific silicon component ratio or the end of the desiliconization reaction can be detected from the change in the time-varying characteristics of the radiant light intensity shown in FIG. 5 (a).

Moreover, the relationship of the time change characteristic shown to Fig.5 (a) is proved by the measured value shown in FIG. The actual measured values in FIG. 8 are the results under specific operating conditions, and the relationship between the radiant brightness and the silicon component ratio depending on the blowing conditions such as the acid feeding conditions and the ratio of other components (carbon, etc.) in the hot metal. Since it may change, it is necessary to grasp in advance the difference in the time change characteristic of the fire point radiance with respect to the operating conditions, etc., and to appropriately detect the change in the time change characteristic.

And the signal processing apparatus 17 calculates | requires the radiant light intensity of the radiated light which the fire point 5 emits from the image input from the CMOS-CCD camera 15 from the blowing start time, and calculates | requires the radiation | emission light which this calculated | required fire point 5 emits. The time change of the radiant light luminance is monitored, and from this time change, the start of the desiliconization reaction and the end of the desiliconization reaction are detected.

FIG. 6 is a flowchart showing the above-described detection operation of the signal processing device 17.
An oxygen supply source (not shown) is instructed to start blowing, and starts blowing oxygen 8 to the hot metal 2 accommodated in the furnace body 1 via the lance 3 (step S1). As a result, a fire point 5 is generated below the acid feed hole 4 at the lower end of the lance 3. Then, it is confirmed that a portion including the acid feed hole 4 at the lower end of the lance 3 shown in FIG. 4 appears in the image input from the CMOS-CCD camera 15. If the acid feed hole 4 does not appear in the image, a brightness level adjustment signal is sent to the CMOS-CCD camera 15 to adjust the sensitivity of the CMOS-CCD camera 15 so that the acid feed hole 4 appears in the image. (S2).

  For example, after a unit time (sampling time) Δt of 1 second or the like has elapsed (S3), an image input from the CMOS-CCD camera 15 is read (S4). Next, a process of calculating the representative radiant light luminance S of the image read this time is performed (S5).

  FIG. 7 is a subroutine showing the processing for calculating the representative radiant light luminance. The maximum luminance and the minimum luminance in the image read this time are obtained (Q1) and compared with a preset reference value. If the maximum luminance value is smaller than the reference value, or if the minimum luminance value is larger than the reference value (Q2), it is determined that normal fire spot radiation is not imaged, and the process ends (Q8).

Next, a high luminance portion in the image, that is, a portion corresponding to the acid feed hole 4 is extracted by binarization processing or the like (Q3, Q4). Here, for example, a reference value for performing extraction by binarization processing is determined in advance or determined in consideration of the maximum luminance and the minimum luminance in the image. Next, the area on the image of the portion corresponding to the acid feed hole 4 extracted by binarization or the like is calculated, and the luminance for each image pixel constituting the portion corresponding to the acid feed hole 4 is calculated. (Q5).

At this time, if there are a plurality of high-luminance portions in the image, it is determined whether or not the hole is an acid feed hole 4 from the position and size of the high-luminance portions. As a determination criterion, the closest to the assumed position and the assumed area (or the position and area of the acid delivery hole 4 at the previous processing) of the acid delivery hole 4 on the image that can be confirmed in advance is judged as the acid delivery hole 4. .

  Next, the area on the image corresponding to the acid feed hole 4 is compared with a preset reference value (Q6). When the area is small with respect to the reference value or extremely large with respect to the reference value In this case, the processing is terminated without calculating the luminance level on the assumption that the acid feed hole 4 is blocked due to adhesion of slag, metal, etc., the incident luminance is reduced, or the image is temporarily changed (Q8).

Next, the maximum luminance or the average luminance of the portion corresponding to the acid feeding hole 4 is calculated using the luminance of each pixel of the portion corresponding to the extracted oxygen feeding hole 4. If the area of the portion corresponding to the extracted acid feed hole 4 is larger than the specified value, the average luminance is set as the representative radiant light intensity S of the portion corresponding to the extracted acid feed hole 4. If the area of the portion corresponding to the extracted acid feed hole 4 is smaller than the specified value, the maximum luminance is set as the representative radiant light luminance S of the portion corresponding to the extracted acid feed hole 4 (Q7).

Note that, as described above, the calculation of the representative radiant light luminance S may be a method of calculating the maximum value of the acid hole portion (high luminance portion), a method of calculating the average value of the acid hole portion, or the like. Any processing can be used as long as the correspondence with the actual fluctuation of the fire point radiation light can be obtained.
When the calculation of the representative radiant light luminance S is finished, this subroutine is finished (Q8), and the process returns to S6 in FIG.

  When the normal representative radiant light intensity S is obtained in S5 of FIG. 6, the moving average of the representative radiant light intensity S obtained this time and the representative radiant light intensity S obtained last time is calculated. The moving average is newly set as the current radiant light intensity S (S6). By adopting the moving average in this way, the noise component included in the radiated light luminance S can be reduced.

As shown in FIG. 5 (b), at the initial stage of the luminance calculation, the radiant light luminance S before the start of blowing is set as S0 and stored as the initial luminance. A difference ΔS between the current radiant light luminance S and the moving average of the previous radiant light luminance is calculated (S7).

  When the luminance difference ΔS is less than the predetermined specified value Sa shown in FIG. 5B (ΔS <Sa) or (S8), ΔS is between the predetermined specified values Sb and Sc. If (Sc <ΔS <Sb), ΔS is equal to or less than the specified value Sc, or ΔS is equal to or greater than the specified value Sb (S9), and the change flag 1 is 0 (S10), the process returns to S3. The capturing process and the brightness calculation process from the image are repeated. As shown in FIG. 5B, the magnitude relationship between the respective prescribed values Sa, Sb, and Sc is Sc <Sb <Sa.

  In S8, when the brightness difference ΔS is equal to or greater than the prescribed value Sa, it is determined that the desiliconization reaction in which a fire point is generated by the acid transmission has started, and a desiliconization reaction start signal is output (S11). The change flag 1 is set to 1 (S12). When the change flag 1 is 1 and ΔS is between the specified values Sb and Sc (Sc <ΔS <Sb), the luminance calculation process is repeated.

In S10, when the change flag 1 is 1, the luminance difference ΔS is equal to or less than the specified value Sc, and when the luminance value is equal to the initial luminance S0 (S≈S0), blowing is performed. It is determined that the process is interrupted (finished above), the change flag 1 is set to 0, the initial luminance S0 is set to 0, the determination process is interrupted, and the process returns to the initial state.

  In S10, when the change flag 1 is 1 and the luminance difference ΔS is not less than Sb, it is determined that the specific measurement component ratio has been reached (passed), and the change flag 2 is set to 1. In addition, a specific component ratio arrival detection signal is output (S13). When the change flags 1 and 2 are 1, the brightness difference ΔS is less than Sc and the brightness S is greater than or equal to the initial brightness S0, it is determined that the desiliconization reaction has ended, and the change flag 1 and 2 is set to 0, and a desiliconization reaction end detection signal is output.

  Then, the end of blowing is instructed to an oxygen supply source (not shown), and the blowing of oxygen 8 to the hot metal 2 accommodated in the furnace body 1 is ended (S15).

  FIG. 8 shows the radiant light intensity S of the fire point 5 calculated by the signal processing device 17 using the above-described maximum value calculation method, with the time t from the blowing start time as the horizontal axis. is there. In FIG. 8, at each time t from the start time of blowing, the hot metal 2 in the furnace body 1 is sampled, and the measurement result of the actual component ratio of silicon Si in the hot metal 2 is also shown. ing.

  In the hot spot radiation measuring method configured as described above, the portion including the acid feed hole 4 at the lower end of the lance 3 is used with the CMOS-CCD camera 15 housed in the measuring case 13 provided at the upper end of the lance 3. An image is taken from the inside of the lance 3, and the signal processor 17 obtains the radiant light intensity S of the radiated light emitted from the fire point 5 generated below the acid feed hole 4 at the lower end of the lance from the luminance distribution of the photographed image. Yes. Therefore, even if the position of the acid feed hole portion in the image taken due to disturbance factors such as slag, metal adhesion and generation of fumes (smoke) on the acid feed hole 4 portion at the lower end of the lance 3 is shifted, The radiant light intensity S of the radiant light emitted from the fire point 5 generated below can be obtained more accurately.

  Further, the time point of starting the change of the component ratio of, for example, silicon Si in the hot metal 2 and the time point when the component ratio of, for example, silicon Si in the hot metal 2 reaches the target component ratio are detected from the time change of the radiant light intensity S at the hot spot 5. Therefore, even if the level of the incident light from the lower end of the lance 3 fluctuates greatly due to disturbance factors as described above, the change of the components of the hot metal 2 accommodated in a vessel such as a converter or a pan is changed. Can be detected accurately online.

  In the above-described hot spot radiation measuring method of the embodiment, the component to be monitored of the hot metal 2 is silicon Si, but the component to be monitored of the hot metal 2 can be carbon C. In this case, it is necessary to change the time change characteristic of the radiant light luminance S and the time change characteristic of the component ratio in FIG. 5 to the time change characteristic corresponding to the carbon C, respectively.

  Furthermore, in the embodiment, as the image processing for obtaining the representative radiant light luminance S, the processing shown in FIG. 7 is performed. However, as long as an equivalent result is obtained, there is no problem even if the processing procedure is different. . Depending on the driving (operation) conditions and the image capturing conditions, the change in the radiated light intensity S of the fire point 5 can be detected by simple processing such as detecting the maximum brightness in a simple image or calculating the brightness at a certain position in the image. Measurement and monitoring can also be performed, and the processing load can be reduced.

(Appendix)
The following claims are described in the original application, and the invention described in the claims of the original application is disclosed in this specification.

(Claim 1)
In the upper blowing process,
Take a picture of the part containing the acid feed hole at the lower end of the lance that performs acid feeding through the lance,
From the luminance distribution of the photographed image, obtain the radiant luminance of the radiant light emitted from the fire point generated below the acid feed hole at the lower end of the lance,
A hot spot radiation measuring method, characterized in that a change in the hot metal component is detected from the time change of the radiated light luminance obtained.

(Claim 2)
The upper end portion of the lance is provided with an opening through which the acid feeding hole at the lower end of the lance can be directly seen, and a portion including the acid feeding hole at the lower end of the lance is photographed through the opening. 1. The hot spot radiation measuring method according to 1.

(Claim 3)
From the luminance distribution of the photographed image, extract the portion corresponding to the acid feed holes in the image,
Obtain the maximum brightness or average brightness of the portion corresponding to the acid feed hole as the representative brightness of the portion corresponding to the acid feed hole,
3. The hot spot radiation measuring method according to claim 1, wherein the obtained representative brightness is a radiant light brightness of the radiant light emitted from the fire spot.

(Claim 4)
The hot spot radiation measuring method according to claim 3, wherein a calculation method of the maximum luminance or the average luminance of the representative luminance is selected according to an area of a portion corresponding to the acid feed hole in the extracted image.

(Claim 5)
Take a picture of the part containing the acid feed hole at the lower end of the lance with the camera through the lance,
The hot spot radiation measurement according to any one of claims 1 to 4, wherein brightness adjustment is performed so that the brightness of light incident on the camera from a portion including the acid feed hole falls within a sensitivity range of the camera. Method.

(Claim 6)
An imaging means for photographing a portion including an acid feeding hole at the lower end of the lance, which is set at an upper end opening of a lance installed to feed acid from above into a container containing at least hot metal,
Image processing means for calculating the brightness of the acid feed hole in the image photographed by the photographing means;
A fire point radiation measuring apparatus comprising: a signal processing means for detecting a change in a hot metal component based on the calculated temporal change in the brightness of the acid feed hole.

  DESCRIPTION OF SYMBOLS 1 ... Furnace body, 2 ... Hot metal, 3 ... Lance, 4.4a, 4b, 4c, 4d ... Acid feed hole, 5 ... Fire point, 6 ... Branch pipe, 8 ... Oxygen, 12 ... Opening, 13 ... Measurement case, DESCRIPTION OF SYMBOLS 14 ... Lens, 15 ... CMOS-CCD camera, 16 ... Communication cable, 17 ... Signal processing apparatus

Claims (4)

In the upper blowing process,
Even if the position of the oxygen delivery hole fluctuates from the upper part of the lance and from the inside of the lance, the image of the oxygen delivery hole is included in the image at the portion including the acid delivery hole at the lower end of the lance that performs acid delivery. So that the field of view is widened ,
From the luminance distribution of the photographed image, obtain the radiant luminance of the radiant light emitted from the fire point generated below the acid feed hole at the lower end of the lance,
A hot spot radiation measuring method, wherein a change in a hot metal component is detected from a relative temporal change amount of a moving average value of radiant light luminance obtained from a luminance distribution of the image. The upper end portion of the lance is provided with an opening through which the acid feeding hole at the lower end of the lance can be directly seen, and a portion including the acid feeding hole at the lower end of the lance is photographed through the opening. 1. The hot spot radiation measuring method according to 1. From the luminance distribution of the photographed image, extract the portion corresponding to the acid feed holes in the image,
Obtain the maximum brightness or average brightness of the portion corresponding to the acid feed hole as the representative brightness of the portion corresponding to the acid feed hole,
3. The hot spot radiation measuring method according to claim 1, wherein the obtained representative brightness is a radiant light brightness of the radiant light emitted from the fire spot. A hot spot radiation measuring apparatus for performing the hot spot radiation measuring method according to claim 1,
An imaging means that is set at an upper end opening of a lance installed to feed acid from above into a container containing at least hot metal, and shoots a portion including the acid feeding hole at the lower end of the lance from the inside of the lance,
Image processing means for calculating the luminance distribution of the acid feed holes in the image taken by the photographing means;
Signal processing means for detecting a change in the hot metal component based on a relative temporal change amount of a moving average value of the brightness of the acid feed hole calculated from the brightness distribution of the acid feed hole. Fire point radiation measuring device.

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