JP4260673B2 - 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 supplied from the blast furnace and scrap prepared separately as a main raw material. After adding a secondary raw material such as lime to this, oxygen is blown through the lance from above and contained in the hot metal. It has the function of removing substances other than iron such as silicon Si and carbon C by oxidation, refining steel with a target component (composition) and temperature, and supplying it to the next casting process. Yes. 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 melting component by performing it has been proposed.

  Further, in Patent Document 2, there is a method in which a laser beam is not used, and a radiant light from a fire point generated below (front) of an acid lance is spectroscopically analyzed, and a hot metal component is estimated based on the analysis result. 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 radiation from a fire point generated below (front) the lance incident from the tip of the lance. The 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, the method of measuring the radiation from the hot metal via the lance or furnace body nozzle described in Patent Document 3 to measure (calculate) the temperature has the same problems and fluctuations in the effective emissivity of the hot metal. Therefore, 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 one of the synchrotron radiation emitted from the hot spot generated below the feed hole at the lower end of the lance for feeding acid in the top blowing converter blowing method. Alternatively, the spectral radiance brightness at a plurality of wavelengths is measured through the lance, and a portion including the acid feeding hole at the lower end of the lance is photographed through the lance, and the shape of the portion corresponding to the acid feeding hole in the photographed image An attribute is extracted, and when the extracted shape attribute satisfies a predetermined condition, a change in the hot metal component is detected from a temporal change in the measured spectral radiant light luminance.

  First, in the hot spot radiation measuring method configured as described above, the radiant brightness of the radiant light emitted from the fire point generated below the acid hole at the lower end of the lance is obtained, and the time difference of the radiant light brightness is used to determine the hot metal emission. An operation principle capable of detecting a change in component 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 hot metal, the state of molten steel (temperature, weight, etc.) and the conditions of acid delivery from the lance, but the relative change in radiant brightness over time, that is, the time of radiant brightness. Change in transition pattern (change from a constant radiant brightness at the start of blowing to a state where the brightness decreases or increases during the blowing, from a decrease or increase at the end of blowing to a constant radiant brightness state The change etc.) is considered to be 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 emitted light from the fire point and detecting the relative change over time, or to reach 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 of the hot metal component is detected from the relative temporal change of the radiant brightness of the hot spot, not the result of the spectral analysis at each time 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 the components of the hot metal contained in a vessel such as a converter or a pan.

  In addition, depending on the type of reaction such as desiliconization reaction or decarburization reaction at the hot spot, the temporal change in the spectral radiant brightness of one or more wavelengths where the hot spot radiance is notable is selected selectively. By observing, it is possible to detect the change of the hot metal more appropriately and stably as compared with the case of observing the temporal change of the radiant light luminance before the spectroscopic analysis.

  However, the measured spectral radiant brightness naturally changes depending on the amount of light emitted from the fire point radiated light that is incident from the acid hole, so the change in the measured spectral radiant brightness changes due to disturbance factors. It may be difficult to determine whether the fire point radiance itself has changed.

  Therefore, in the present invention, the portion including the acid feed hole at the lower end of the lance is photographed, and based on the shape of the photographed acid feed hole, slag, metal adhesion to the acid feed hole portion at the lower end of the lance, fume, etc. The disturbance factor is grasped, and the disturbance factor is prevented from affecting the measurement result.

  In another invention, in the fire point radiation measuring method of the above-described invention, when the extracted shape attribute satisfies a predetermined condition, after correcting the measured spectral radiant light intensity with the extracted shape attribute, The change of the hot metal component is detected from the time change of the corrected spectral radiant light luminance.

  In the hot spot radiation measuring method configured as described above, the actual shape of the acid feed hole is greatly influenced by adhesion of slag and metal. Moreover, the measured spectral radiant light brightness changes according to the substantial shape of the acid feed hole. Therefore, by correcting the measured spectral radiant light brightness with the shape attribute of the picked-up oxygen hole, it is possible to more correctly detect the change in the hot metal component.

  Another invention adopts an area as a shape attribute in the fire point radiation measuring method of the invention described above.

  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. Spectral radiant brightness at one or a plurality of wavelengths of radiation emitted from a fire point generated below the hole is measured, and a portion including an acid feed hole at the lower end of the lance is photographed.

  In the hot spot radiation measuring method configured as described above, a portion including the acid feed hole at the lower end of the lance is photographed from the upper end of the lance through the inside of the lance, and the emitted light spectrum of the fire spot generated below the feed hole is obtained. Since the radiant light intensity is measured, the structure of the lance is simplified, the incorporation of the lance and measurement equipment into the facility is simplified, and the maintenance work is simplified.

  Still another invention is the above-described fire point radiation measuring method according to the invention, wherein the spectral radiant brightness at one or a plurality of wavelengths of the radiated light emitted from the fire point is measured with a linear wavelength distribution filter (LVF) and a line light reception. Measurement is performed using a spectroscopic sensor constituted by the sensor.

  In this way, the spectroscopic measurement sensor that measures the spectral radiant brightness at one or more wavelengths of the radiated light emitted from the fire point is composed of a linear wavelength distribution filter and a line light receiving sensor, thereby making the spectroscopic sensor compact and lightweight. The spectroscopic sensor can be easily attached to the upper end of the lance.

According to another invention, in the fire point radiation measuring method of the above-described invention, a portion including the acid feed hole at the lower end of the lance is photographed by a CCD camera having an incident light amount adjusting means.
Since this CCD camera has a much wider allowable range of incident light luminance than a normal camera, the above-described effects of the invention can be further improved.

  Still another invention of a hot spot radiation measuring device is installed in an upper end opening of a lance that feeds acid from above into a container containing at least hot metal, and propagates in the lance from the lower portion of the feed hole at the lower end of the lance. The light branching means for branching the light into two propagation paths, and the radiant brightness or spectral emission of the radiation emitted from the fire point generated below the acid feed hole at the bottom of the lance using one of the propagation paths in this light branching means Light receiving means for measuring the light intensity, photographing means for photographing an image of the lower end of the lance using the other propagation path in the light branching means, means for adjusting the incident light level to the photographing means, and photographing means The image of the lower end portion of the lance photographed in this way is input, and the image processing means for calculating the shape attribute of the portion corresponding to the acid feed hole in the image, and the shape attribute calculated by the image processing means, the light receiving Measured by means Luminance correction means for correcting the radiant light intensity or spectral radiant light intensity, and signal processing for detecting a change in the hot metal component based on the temporal change of the radiant light intensity or spectral radiant light intensity corrected by the luminance correction means. Means.

  The fire point radiation measuring apparatus configured as described above can achieve substantially the same operational effects as the above-described fire point radiation measuring method.

  In the hot spot radiation measuring method and apparatus therefor according to the present invention, the measurement of the spectral radiant brightness of the radiation emitted from the fire spot generated below the oxygen feed hole at the lower end of the lance and the photographing of the portion including the oxygen feed hole are carried out. However, when the shape attribute of the acid feed hole in the image obtained by photographing satisfies a predetermined condition, a change of the hot metal component is detected from the time change of the measured spectral radiant light luminance.

  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.

  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 is composed of a 50 mm diameter inner pipe 3a through which oxygen 8 flows and an outer pipe 3b through which cooling water 10 surrounding the inner pipe 3a flows. The structure has a structure, and four 10 mm-diameter acid feed holes 4 a, 4 b, 4 c, and 4 are formed 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. An optical branching device 14 composed of a half mirror 14a and a mirror 14b is disposed at a position facing the opening 12 of the measurement case 13. A monochrome CCD camera 16 is attached via a lens 15 at a position opposite to the half mirror 14 a of the optical branching device 14. A spectroscopic sensor 19 is attached to the optical branching device 14 at a position opposite to the mirror 14 b via a lens 17 and a light diffusion plate 18.

  The opening 12 of the measurement case 13 incorporates protective glass for protecting the optical branching device 14, the lenses 15, 17, the CCD camera 16, and the spectroscopic measurement sensor 19 from an external adverse environment. This protective glass is air purged as necessary.

  The light diffusing plate 18 emits radiated light emitted from the fire point 5 below the acid feed hole 4 at the lower end of the lance 3 and incident through the mirror 14 b and the lens 17 of the optical branching device 14. Has a function of uniformly entering the light receiving surface. However, the radiated light can be directly incident on the light receiving surface of the spectroscopic sensor 19 without using the light diffusing plate 18.

  As shown in FIG. 3A, the spectroscopic measurement sensor 19 includes a linear wavelength distribution filter 20 (LVF), a SSGC (Stainless Steel Grating Collimator) 21, and a line light receiving sensor 22. .

  The linear wavelength distribution filter 20 is a plate-shaped prism having transmission wavelength characteristics distributed in a one-dimensional direction. When uniform light is incident through the lens 17 from below in FIG. The light of each wavelength according to each transmission position distributed in the horizontal direction in Fig. 3A is output upward in the figure. The light of each wavelength output from each transmission position of the linear wavelength distribution filter 20 is incident on each light receiving element constituting the line light receiving sensor 22 disposed above the linear wavelength distribution filter 20. Each light receiving element of the line light receiving sensor 22 converts the intensity of light of a designated wavelength into an electric signal and outputs it.

  Note that an SSGC 21 is inserted between the linear wavelength distribution filter 20 and the line light receiving sensor 22 in order to reduce the influence of interference between wavelengths.

  Therefore, the spectroscopic measurement sensor 19 configured in this way performs spectroscopic analysis on the emitted light emitted from the fire point 5 below the acid feed hole 4 at the lower end of the lance 3 as shown in FIG. Then, each spectral radiant light brightness P at each wavelength is measured and sent to the signal processing device 24 including an information processing device such as a computer via the communication cable 23.

  The characteristic of the spectroscopic measurement sensor 19 is determined by the characteristic of the linear wavelength distribution filter 20 and the characteristic of the line light receiving sensor 22, and the spectroscopic measurement sensor 19 of this embodiment can perform spectroscopic measurement in the wavelength region of 600 nm to 1100 nm. It is also possible to change the measurement wavelength range by using the linear wavelength distribution filter 20 and the line light receiving sensor 22 having other characteristics.

  FIG. 4 shows the spectral radiant light intensity P at the specific wavelength (1020 nm) of the radiated light from the fire point 5 measured by the spectroscopic sensor 19, with the time t from the blowing start time as the horizontal axis. It is. In the figure, “KS-1” and “KS-2” indicate differences in blowing conditions.

  In FIG. 4, the hot metal 2 in the furnace body 1 is sampled at each time t from the start time of blowing and the actual component ratio measurement results of silicon Si and carbon C in the hot metal 2 are also shown. It is described at the same time.

  On the other hand, the CCD camera 16 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 half mirror 14a and the lens 15 of the optical branching device 14, and this photographed two-dimensional image. Is transmitted to the above-described signal processing device 24 via the communication cable 25.

  The lens 15 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 CCD camera 16. Specifically, a CCD camera 16 is used in which a lens 15 having 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. The CCD camera 16 captures a field of view equivalent to 200 × 250 mm at the tip of the lance. Then, the CCD camera 16 is positioned on the optical branching device 14 via the lens 15 so that the center positions of the four acid feed holes 4a to 4d at the lower end of the lance 3 are located at the center of the photographed image.

  In the case of the embodiment, each of the acid feeding holes 4a to 4d in the image of the portion including the acid feeding hole 4 at the lower end of the lance 3 photographed by the CCD camera 16 has a size of 1/15 or less with respect to the entire image. 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 15 used for photographing and to 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 associated with the operation. The relative position of the acid delivery hole 4 with respect to the CCD camera 16 may be displaced due to the bending (deflection) of the lance 3 itself due to the above, etc., so that the acid delivery hole 4 may be outside the field of view of the image. The range is set wide.

  In the embodiment, a CCD camera 16 (for example, a CMOS-CCD camera) having a wide dynamic range with respect to a normal CCD camera can be used as a camera that captures a portion including the acid feed hole 4 at the lower end of the lance 3. is there. As shown in FIG. 5, while the conventional camera has a linear relationship between the incident luminance with respect to the camera and the luminance in the captured image, the CMOS-CCD camera 16 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, the CMOS-CCD camera 16 has a wide range of brightness that can be photographed. Therefore, even when high-intensity light is incident or fluctuates, particularly in the case of fired light, saturation does not occur on the image, and appropriate values are obtained. It is possible to obtain an image of the acid feed hole.

  In the combination of a conventional CCD camera and lens, an automatic adjustment mechanism for the lens diaphragm and a control mechanism for the shutter speed are provided to adjust the incident luminance level to the camera and the camera sensitivity to adjust the captured image and adjustment. The incident light luminance is calculated from the adjustment amount in the mechanism, and it is possible to deal with a substantially wide incident light range.

  FIG. 6 shows a portion including the oxygen feed hole 4 at the lower end of the lance 3 photographed by the CMOS-CCD camera 16 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.

  7 (a), (b), (c), and (d), the lance 3 is used to start the blowing operation of blowing oxygen 8 to the hot metal 2 accommodated in the furnace body 1. The images of the portion including the acid feed hole 4 at the lower end of the lance 3 taken by the CMOS-CCD camera 16 at the elapsed time t = 600 seconds, t = 1200 seconds, t = 1500 seconds, t = 1600 seconds are shown. It can be understood that the shape and area of the portion corresponding to the acid feed hole 4 in the image are changed with the passage of time due to slag and metal adhesion to the actual acid feed hole. In particular, when adhesion to the tip of the lance occurs, it can be seen that some of the plurality of acid delivery holes 4 cannot be confirmed on the image.

  The CMOS-CCD camera 16 continuously shoots the portion including the acid feed hole 4 at the lower end of the lance 3 and communicates the image of the taken portion including the acid feed hole 4 at the lower end of the lance 3 as an image (video) signal. The signal is sent to the signal processing device 24 via the cable 25.

  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, the substance to be detected among the supply time t of the oxygen 8 from the lance 3, the component ratio (concentration) of silicon Si, and the plurality of spectral radiant luminances of the radiated light emitted from the fire point 5 (this implementation) In the embodiment, the relationship with the spectral radiant light luminance P of a specific wavelength determined by silicon Si) changes roughly as shown in FIG.

  Prior to the start of blowing, no hot spot is generated in front of the lance (downward), but there is high-temperature hot metal in front of the lance, so the brightness is relatively low compared to the radiant brightness from the hot spot. Observed synchrotron radiation.

  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.

  After the hot spot is generated, the radiant brightness increases with the progress of blowing (decrease in the silicon component ratio), but at a certain point after the start of blowing, the radiant brightness becomes a substantially constant value. At this time, the silicon component ratio in the hot metal is a minute value, and it is judged that the desiliconization reaction is almost completed.

  The time characteristic of the spectral radiant light intensity P and the silicon Si component ratio shown in FIG. 8A is verified by the actually measured values shown in FIG.

  Then, the signal processing device 24 calculates the image from the image input from the CMOS-CCD camera 16 from the blowing start time and the spectral radiant brightness P of the radiated light emitted from the fire point 5 input from the spectroscopic measurement sensor 19. When the conditions determined by the above conditions are satisfied, the time change of the spectral radiant brightness P of the emitted light emitted from the fire point 5 is monitored, and from this time change, the desiliconization reaction has occurred, the desiliconization reaction Detect that has ended.

9 and 10 are flowcharts showing an example of the above-described detection operation of the signal processing device 24. FIG.
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.

  For example, after elapse of a unit time (sampling time) Δt such as 1 second (S2), among the spectral radiant brightness of each wavelength input from the spectroscopic measurement sensor 19, a substance to be detected for component change (in this embodiment, silicon The spectral radiant light brightness P of a specific wavelength determined by Si) is read (S3). At the same time, an image input from the CMOS-CCD camera 16 is read (S4).

  Next, the luminance of each pixel constituting the two-dimensional image of the portion including the acid feeding hole 4 at the lower end of the lance 3 read this time is binarized with a predetermined reference value, so that the high luminance portion in the image, that is, the acid feeding A portion corresponding to the hole 4 is extracted (S5). Here, for example, the 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 A on the image of the portion corresponding to the acid feed hole 4 extracted by binarization or the like is calculated (S6).

  The area A on the image of the portion corresponding to the calculated oxygen delivery hole 4 is on the image when no slag, metal adhesion, or fume is generated in the actual acid delivery hole 4 at the lower end of the lance 3. It is determined whether or not it is within an allowable range AS-ΔA defined by a reference area As and a predetermined range ΔA (S7). For example, as shown in FIG. When it is out of the range, it is determined that the spectral radiant light intensity P read this time is far away from the actual spectral radiant light intensity at the fire point 5, and the spectral radiant light intensity P is invalidated and discarded. (S8). Then, the process returns to S2, and after the unit time Δt has elapsed, the next spectral radiation light luminance P is read (S3).

  For example, when the area A on the image corresponding to the acid feed hole 4 is within the allowable range AS-ΔA (S7) as shown in FIG. P is corrected by the area A on the image (S9). Specifically, the current spectral radiant light luminance P ′ is obtained by multiplying the spectral radiant light luminance P by [reference area As / area A]. The reason for this is that even if the spectral radiant light brightness P at the fire point 5 is constant, the amount of light incident on the spectroscopic sensor 19 decreases when the actual area of the acid delivery hole 4 decreases, and the measured spectral radiation. This is because the light luminance P decreases, and it is necessary to compensate for this decrease.

  Here, when there is no adhesion to the lance and [reference area As on the image.apprxeq.area A on the image], no particular correction is performed, and P '= P.

  As shown in FIG. 8B, the radiated light luminance before the start of blowing is set as P0 as the initial luminance value and stored as the initial luminance. A difference ΔP between the current (corrected) spectral radiant light intensity P ′ and the previous spectral radiant light intensity is calculated (S10).

  When this luminance difference ΔP is less than a predetermined value Pa (ΔP <Pa) (S11), and when the change flag is 0 (S13), the spectral radiance measurement and calculation processes are repeated. .

  When the brightness difference ΔP is equal to or greater than the specified value Pa (S11), it is determined that a degassing reaction has started due to the generation of a fire point due to acid transmission, and a desiliconization reaction start is output (S14). The flag is set to 1 (S15). When ΔP is between the prescribed values Pa and Pb with the change flag set to 1, the measurement and calculation processing of the spectral radiance is repeated.

  If the change flag is 1 (S13), ΔP is less than or equal to the specified value Pb (S12), and the brightness P ′ is greater than or equal to the initial brightness P0, it is determined that the desiliconization reaction has been completed, A silicon reaction end detection signal is output (S16), and the change flag is set to 0 (S17). 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 (S18).

  Even when ΔP is less than or equal to the specified value Pb, if the luminance value P ′ is equal to the initial luminance P0 (P′≈P0), the blowing is interrupted (finished above). The change flag is set to 0, the initial luminance P0 is set to 0, the determination process is interrupted, and the process returns to the initial state.

  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 to measure the lance 3 with the CCD camera 16 housed in the measuring case 13 provided at the upper end of the lance 3. Take a picture from the inside of 3. At the same time, the spectral radiant brightness P of each wavelength of the radiated light at the fire point 5 below the acid feed hole 4 at the lower end of the lance 3 is measured from the inside of the lance 3 with the spectroscopic sensor 19 housed in the measurement case 13. To do.

  Then, the area A of the shape of the acid delivery hole 4 in the captured images shown in FIGS. 6 and 7 is obtained, which is caused by slag / metal adhesion to the acid delivery hole 4 at the lower end of the lance 3, fume, and the like. Thus, when the obtained area A is out of the allowable range as shown in FIG. 7D, for example, the measured spectral radiant light luminance P is discarded. Further, for example, when the obtained area A is within the allowable range as shown in FIG. 7A, the obtained spectral radiant light luminance P is multiplied by [reference area As / area A]. The spectral radiant light brightness P is corrected. And the change of the component of the hot metal 2 is detected from the time change of the spectral radiant light luminance P after this correction.

  Therefore, even if the actual shape and area of the acid feed hole 4 change due to disturbance factors such as slag, metal adhesion, and generation of fumes (smoke) on the acid feed hole 4 at the lower end of the lance 3, the acid feed hole 4 is changed. The spectral radiant brightness P of the radiant light emitted from the fire point 5 generated below can be obtained more accurately.

  Furthermore, the change start time of the component ratio of, for example, silicon Si in the hot metal 2 and the component of, for example, silicon Si in the hot metal 2 from the time change of the spectral radiant light brightness P at one or a plurality of specific wavelengths of the emitted light at the fire point 5 Since the point in time when the ratio reaches the target component ratio is detected, the change in the hot metal is detected more appropriately and stably than when observing the temporal change in the radiant light luminance before spectroscopic analysis. It becomes possible. As a result, 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 in the components of the hot metal 2 accommodated in a vessel such as a converter or a pan is online. It can be detected accurately.

  Further, by adopting the CMOS-CCD camera 16 and the spectroscopic measurement sensor 19 composed of the linear wavelength distribution filter 19 and the line light receiving sensor 22, the CMOS-CCD camera 16 and the spectroscopic measurement sensor 19 can be easily connected to the lance 3. It can be attached to the upper end.

Schematic diagram of a converter using a blowing process to which a hot spot radiation measuring method according to an embodiment of the present invention is 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 schematic structure and a measurement example of the spectroscopic measurement sensor employ | adopted with the hot spot radiation | emission measurement method of the embodiment The figure which shows the spectral radiant light luminance characteristic (time characteristic) of the radiated light measured with the hot spot radiation measuring method of the embodiment The figure which shows the characteristic of the CCD camera employ | adopted with the hot spot radiation measuring method of the embodiment The figure which shows the picture photoed with the same CCD camera The figure which shows the picture which is similarly photographed with the same 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

Explanation of symbols

  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 ... Optical branching device, 15, 17 ... Lens, 16 ... CCD camera, 18 ... Light diffusing plate, 19 ... Spectral measurement sensor, 20 ... Linear wavelength distribution filter, 21 ... SSGC, 22 ... Line light reception sensor, 23, 25 ... Communication cable, 24 ... Signal processing device

Claims (7)

In the upper blowing process,
Measure the spectral radiant brightness at one or more wavelengths of the emitted light emitted from the fire point generated below the acid feed hole at the lower end of the lance that performs the acid feeding through the lance,
Photographed through the lance the portion containing the acid feed hole at the lower end of the lance,
Extract the shape attribute of the part corresponding to the acid feed hole in this captured image,
A hot spot radiation measuring method, wherein when the extracted shape attribute satisfies a predetermined condition, a change in a hot metal component is detected from a temporal change in the measured spectral radiant light luminance.   When the extracted shape attribute satisfies a predetermined condition, after correcting the measured spectral radiance brightness with the extracted shape attribute, 2. The hot spot radiation measuring method according to claim 1, wherein a change in the component is detected.   3. The hot spot radiation measuring method according to claim 1, wherein the extracted shape attribute is an area.   An opening is provided at the upper end of the lance so that the acid feeding hole at the lower end of the lance can be directly seen, and through this opening, one of the emitted light emitted by a fire point generated below the acid feeding hole at the lower end of the lance. 4. The method for measuring a hot spot radiation according to any one of claims 1 to 3, wherein a spectral radiation brightness at a plurality of wavelengths is measured and a portion including an acid feed hole at a lower end of the lance is photographed.   5. The spectral radiant brightness at one or a plurality of wavelengths of the radiated light emitted from the fire point is measured using a spectroscopic sensor configured by a linear wavelength distribution filter and a line light receiving sensor. The hot spot radiation measuring method according to any one of the above.   5. The hot spot radiation measuring method according to claim 1, wherein a portion including an acid feed hole at a lower end of the lance is photographed by a CCD camera having an incident light amount adjusting unit. An optical branching unit that is installed in an upper end opening of a lance that feeds acid from above into a container that contains at least hot metal, and branches light propagating in the lance from the lower portion of the lance at the lower end of the lance into two propagation paths. When,
Using one propagation path in this light branching means, a light receiving means for measuring the radiant or spectral radiant brightness of the radiated light emitted by the fire point generated below the acid hole at the bottom of the lance,
An imaging means for taking an image of the lower end of the lance using the other propagation path in the optical branching means,
Means for adjusting the incident light level to the photographing means;
An image processing means for inputting an image of the lower end of the lance photographed by the photographing means and calculating a shape attribute of a portion corresponding to the acid feed hole in the image;
Using the shape attribute calculated by the image processing means, brightness correction means for correcting the radiant light brightness or the spectral radiant light brightness measured by the light receiving means,
A fire point radiation measuring apparatus comprising: signal processing means for detecting a change in hot metal component based on a temporal change in the radiant light intensity or spectral radiant light intensity corrected by the luminance correcting means.

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