JP2005315777A - Spark radiation measurement method and apparatus therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To precisely detect a change in the constituent of molten iron accommodated in a container, such as a converter and a pan, even if the level of incident light from the tip of a lance greatly fluctuates by disturbance factors. <P>SOLUTION: In a top-blown blowing method, the radiation light luminance of radiation light generated by sparks generated at the lower portion of an acid sending hole at the lower end of a lance is measured via the lance, and a change in the constituent of molten iron is detected from the time change in the radiation light luminance. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to the top blowing method in which the component (composition) of the hot metal is adjusted to the target component (composition) by blowing oxygen through the lance to the hot metal contained in the converter or pan in the 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 raw 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, it is difficult to continuously monitor the hot metal components, temperature, hot metal amount, etc. 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. Is transmitted to a spectroscopic analyzer outside the furnace and the spectroscopic analysis of the detection light is performed.

  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 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.

  Furthermore, a method of measuring the radiation light from the hot metal via a lance or furnace body nozzle described in Patent Document 3 and measuring (calculating) the temperature, or a laser beam described in Patent Document 1 in the container The method of irradiating the hot metal also has the same problems and the problem that it is difficult to measure the exact temperature of the hot metal because the temperature fluctuates due to fluctuations in the effective emissivity 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 tip of the lance fluctuates greatly due to disturbance factors, the hot metal contained in a vessel such as a converter or a pan is used. Changes in components can be accurately detected online, estimating the progress of blowing processes such as desiliconization and decarburization reactions, and specific conditions such as the start and end of desiliconization and decarburization reactions, and changes in reaction rates 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.

  In order to solve the above-mentioned problem, the hot spot radiation measuring method of the present invention, in the upper blowing method, provides the radiant brightness of the radiated light emitted from the fire point generated below the feed hole at the lower end of the lance that feeds acid. Measurement is performed through a lance, and a change in the hot metal component is detected from the time change of the radiant light luminance.

  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 hole at the lower end of the lance is measured, and the time variation of the radiant light brightness is used to measure the hot metal. An operation principle capable of detecting a change in component will be described.

  Synchrotron radiation at the hot spot is emitted along with combustion and heat generation such as desiliconization and decarburization reactions generated by oxygen supplied from the lance, and the radiant brightness is the reaction state of desiliconization and decarburization at the flashpoint. It depends on.

  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, if 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 changes as the blowing progresses, and the amount of decarburization reaction changes, the amount of heat generated along with the decarburization reaction also changes, and the radiance of the hot spot changes. 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.

  Further, the hot spot radiation measuring method of another invention is the above-described top blowing method, wherein the spectral radiant brightness at a plurality of wavelengths of the radiated light emitted by the fire point generated below the acid feed hole at the lower end of the lance is measured. The change of the hot metal component is detected from the relative time change of each spectral radiant light luminance at a plurality of wavelengths.

  In the hot spot radiation measuring method configured as described above, the spectrum of a plurality of wavelengths in which the hot spot radiance is markedly changed with time according to the kind of reaction such as desiliconization reaction or decarburization reaction at the hot spot is described. By selectively observing temporal changes in radiant brightness, it is possible to detect hot metal changes more appropriately and stably than when observing temporal changes in radiant brightness before spectroscopy. It becomes.

  Further, the hot spot radiation measuring method of another invention is the above-described top blowing method, wherein the spectral radiant brightness at a plurality of wavelengths of the radiated light emitted by the fire point generated below the acid feed hole at the lower end of the lance is measured. The ratio of the spectral radiant light luminance between the plurality of wavelengths is calculated, and the change in the hot metal component is detected from the time change of the ratio of the spectral radiant light luminance between the plurality of wavelengths.

  In the hot spot radiation measuring method configured in this way, the wavelength that varies greatly with time by utilizing the fact that the time change of each spectral radiant brightness at multiple wavelengths of the emitted light emitted from the fire point is different for each wavelength. Even if the level of incident light from the tip of the lance fluctuates greatly due to disturbance factors by calculating the ratio of the spectral radiance brightness between them and detecting the change of the hot metal component from the time change of the ratio of the spectral radiance brightness Therefore, it is possible to suppress the influence of the fluctuation of the light amount due to the disturbance factor, detect only the fluctuation of the radiated light itself from the fire point, and stably measure the change of the hot metal component.

  Another invention is the above-described hot spot radiation measuring method according to the present invention, wherein each spectral radiant brightness at a plurality of wavelengths of the radiated light emitted from the fire spot is expressed by a linear wavelength distribution filter (LVF) and a line light receiving sensor. Measurement is performed using a spectroscopic measurement sensor constituted by:

  Still another invention is the above-described hot spot radiation measuring method according to the invention, wherein 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 observed, and a spectroscopic measurement sensor is arranged at a position opposite to the opening. The spectral measurement sensor measures the spectral radiant light brightness at a plurality of wavelengths of the radiated light emitted from the fire point.

  In this way, the spectroscopic measurement sensor composed of the linear wavelength distribution filter and the line light receiving sensor is arranged at the opening facing position where the acid feeding hole formed at the upper end of the lance can be directly seen, thereby simplifying the structure of the lance. The installation of lances and measuring equipment into the facility is simplified, and maintenance work is simplified.

  Still another invention of a hot spot radiation measuring device is installed at an upper end opening of a lance that feeds acid from above a container that contains at least hot metal, and emits a fire spot that is generated below the feed hole at the lower end of the lance. A light receiving means for measuring the radiant brightness of the light, and a signal processing means for inputting the radiated light brightness output from the light receiving means and detecting a change in the hot metal component based on the temporal change of the radiated light brightness. I have.

  Still another invention of a hot spot radiation measuring device is installed at an upper end opening of a lance that feeds acid from above a container that contains at least hot metal, and emits a fire spot that is generated below the feed hole at the lower end of the lance. Spectral light receiving means for measuring the spectral radiant light brightness at a plurality of wavelengths of light and the spectral radiant light brightness output from the spectral light receiving means are input, and based on the temporal change of each spectral radiant light brightness, Signal processing means for detecting changes in components.

  Still another invention is a spectroscopic measurement sensor in which the spectral light receiving means includes a linear wavelength distribution filter and a line light receiving sensor in the above-described hot spot radiation measuring apparatus.

  Also in the fire point radiation measuring apparatus of each invention configured in this way, it is possible to achieve substantially the same operational effects as the respective fire point radiation measuring methods of the invention described above.

  In the hot spot radiation measuring method and the hot spot radiation measuring apparatus according to the present invention, the radiance of the radiant light emitted from the fire point generated below the acid feed hole at the lower end of the lance or the spectral radiant brightness at a plurality of wavelengths is calculated. Thus, the change of the hot metal component is detected from the relative temporal change of the radiant light luminance or the spectral radiant light luminance at a plurality of wavelengths.

  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 changes in hot metal components contained in containers such as converters and pans online, Estimating the progress of the blowing process such as decarburization reaction, desiliconization, start and end of decarburization reaction, arrival at specific conditions such as change in reaction rate, passage, etc. can be detected accurately . Therefore, implementation of additional blowing, component adjustment, or increase in processing load in the next process can be prevented, and increase in operating time and operating cost can be prevented.

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

(First embodiment)
FIG. 1 is a schematic diagram of a converter using a blowing process to which a hot spot radiation measuring method and a hot spot radiometer apparatus according to a first 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 is provided above the furnace body 1. The lance 3 has a double structure of an inner pipe through which oxygen 8 flows and an outer pipe through which cooling water 10 surrounding the inner pipe flows. Below the oxygen feed hole 4 at the lower end of the lance 3. A fire point 5 is formed. 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. Further, a pair of cooling water hoses 9 and 11 for allowing the cooling water 10 to flow through the outer pipe 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 light receiver 14 is attached at a position facing the opening 12 of the measurement case 13. The light receiver 14 measures the radiant light intensity S of the radiated light emitted from the fire point 5 below the acid feed hole 4 at the lower end of the lance 3 via the lance 3, and the radiated light intensity S is measured via the communication cable 15. Then, the data is sent to the signal processing device 16 including an information processing device such as a computer.

  The opening 12 of the measurement case 13 incorporates a protective glass for protecting the light receiver 14 from an external adverse environment. This protective glass is air purged as necessary.

  In the converter having such a configuration, it is assumed that silicon Si contained in the hot metal 2 housed in the furnace body 1 is oxidized and removed with oxygen 8 supplied from the lance 3 (desiliconization treatment). In this case, the relationship between the supply time t of oxygen 8 from the lance 3, the component ratio (concentration) of silicon Si, and the radiant light intensity S of the radiated light emitted from the fire point 5 is roughly as shown in FIG. To change.

  That is, before the start of blowing, no hot spot is generated in front of the lance (downward), but high-temperature hot metal is present in front of the lance, so that the light emitted from the hot metal is observed at the receiver.

  When blowing (acid feeding) is started, a fire point is generated by the oxygen blown from the lance to the hot metal, and the silicon component ratio in the hot metal is reduced by the desiliconization reaction at the hot point. At this time, the light receiver detects the radiant light from the fire point simultaneously with the generation of the fire point, and an increase in the radiant light intensity is observed with the progress of blowing (decrease in the silicon component).

  As the blowing proceeds and the desiliconization reaction proceeds, the radiant brightness further increases, but at a certain point after the start of blowing, the radiant intensity becomes substantially constant. 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.

  And the signal processing apparatus 16 monitors the time change of the radiant light luminance of the radiated light which a fire point emits from the blowing start time, and detects the completion | finish of a desiliconization reaction.

FIG. 2 is a flowchart showing the above-described detection operation of the signal processing device 16.
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 a unit time (sampling time) Δt such as 1 second has elapsed (S2), the radiant light intensity S input from the light receiver 14 is read (S3). Next, a moving average between the radiant light intensity S read this time and the radiant light intensity S read last time is calculated, and this moving average is newly set as the current radiant light intensity S (S4). By adopting the moving average in this way, the noise component included in the radiated light luminance S can be reduced.

  Then, the difference ΔS between the current radiant light intensity S and the moving-averaged previous radiant light intensity S is calculated (S5). When the difference ΔS is less than a predetermined value Sa (S6), when the difference ΔS exceeds a predetermined value Sb (where Sa> Sb) (S7), or when the difference ΔS is a predetermined value If it is equal to or less than Sb (S7) and the change flag remains 0 (S8), the process returns to S2, and after the unit time (sampling time) Δt has elapsed, the next radiation supplied from the light receiver 14 The light intensity S is read (S3).

  When the difference ΔS between the current radiant light intensity S and the moving average of the previous (or any number of previous times) radiant light intensity S is greater than or equal to a predetermined value Sa (S6), a fire point is generated, It is determined that the desiliconization reaction has started, a reaction start signal is output (S9), the change flag is set to 1 (S10), and the process returns to S2.

  When the difference ΔS is equal to or less than the specified value Sb (S7) and the change flag is set to 1 (S8), it is determined that the silicon Si component ratio has reached the target component ratio, and the desiliconization reaction An end signal is output (S11), and the change flag is cleared to 0 (S12). 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 (S13).

  In the hot spot radiation measuring method of the first embodiment configured as described above, since the time when the desiliconization reaction of the hot metal 2 is completed is detected from the time change of the radiant light intensity S at the hot spot 5, Even if the level of incident light from the tip of the lance 3 fluctuates greatly due to disturbance factors, changes in the components of the hot metal 2 accommodated in a vessel such as a converter or a pan can be accurately detected online.

  Note that the time change characteristic of the hot spot radiance in the desiliconization reaction shown in the hot spot radiation measurement method of the first embodiment described above changes depending on the acid feeding conditions and the component ratio of other components (carbon, etc.) in the hot metal. Therefore, it is necessary to grasp in advance the difference in the time variation characteristic of the fire point radiance with respect to these conditions, and to appropriately adjust the judgment criterion of the time variation characteristic in the signal processing device.

  In addition, here, the desiliconization reaction is targeted, and the end of the desiliconization reaction is detected by a change in the hot spot radiance. However, the decarburization reaction can also be targeted. In this case, it is necessary to grasp the time change characteristic of the fire point radiance and the time change characteristic of the carbon component ratio in the decarburization reaction.

(Second Embodiment)
FIG. 4 is a schematic view of a converter using a blowing process to which the hot spot radiation measuring method and the hot spot radiation measuring apparatus according to the second embodiment of the present invention are applied. The same parts as those in the schematic diagram of the converter to which the hot spot radiation measuring method and the hot spot radiation measuring apparatus of the first embodiment shown in FIG. 1 are applied are denoted by the same reference numerals, and detailed description of the overlapping parts is omitted.

  In the converter to which the hot spot radiation measuring method of the second embodiment is applied, a lance 3 is provided above the furnace body 1 in which the hot metal 2 is stored. 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.

  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 spectroscopic measurement sensor 17 is accommodated via a light diffusion plate 18 at a position facing the opening 12 in the measurement case 13. The opening 12 incorporates a protective glass for protecting the spectroscopic measurement sensor 17 from an external adverse environment. This protective glass is air purged as necessary.

  The light diffusing plate 18 has a function of causing the radiated light emitted from the fire point 5 below the acid feed hole 4 at the lower end of the lance 3 to uniformly enter the light receiving surface of the radiated light spectroscopic measurement sensor 17. However, the radiated light can be directly incident on the light receiving surface of the spectroscopic sensor 17 without using the light diffusing plate 18. Further, it is possible to increase the amount of light incident on the spectroscopic measurement sensor 17 by condensing the radiated light using an optical system constituted by a lens or the like.

  As shown in FIG. 5A, the spectroscopic measurement sensor 17 includes a linear wavelength distribution filter 19 (LVF: Linear Variable Filter), an SSGC (Stainless Steel Grating Collimator) 20, and a line light receiving sensor 21. .

  The linear wavelength distribution filter 19 is a plate-shaped prism whose transmission wavelength characteristics are distributed in a one-dimensional direction. When uniform light is incident from below in FIG. 5A, the linear wavelength distribution filter 19 in FIG. The light of each wavelength according to each transmission position distributed in the horizontal direction is output upward in the figure. The light of each wavelength output from each transmission position of the linear wavelength distribution filter 19 is incident on each light receiving element constituting the line light receiving sensor 21 disposed above the linear wavelength distribution filter 19. Each light receiving element of the line light receiving sensor 21 converts the intensity of light having a designated wavelength into an electric signal and outputs the electric signal.

  The SSGC 20 is inserted between the linear wavelength distribution filter 19 and the line light receiving sensor 21 in order to reduce the influence of interference between wavelengths.

  Therefore, the spectroscopic measurement sensor 17 configured as described above is configured so that the light emitted from the fire point 5 below the acid feed hole 4 at the lower end of the lance 3 has each spectrum at each wavelength as shown in FIG. The radiant light brightness P is measured and sent to the signal processing device 22 including an information processing device such as a computer via the communication cable 15.

  The characteristic of the spectroscopic measurement sensor 17 is determined by the characteristic of the linear wavelength distribution filter 19 and the characteristic of the line light receiving sensor 21, and the spectroscopic measurement sensor 17 of this embodiment can perform spectroscopic measurement in the wavelength range of 600 nm to 1100 nm. Note that it is also possible to change the measurement wavelength range by using the linear wavelength distribution filter 19 and the line light receiving sensor 21 having other characteristics.

  FIG. 7 shows the spectral characteristic (wavelength characteristic) of the emitted light from the fire point 5 measured by the spectroscopic measurement sensor 17 using the time t from the blowing start time as a parameter.

  FIG. 8 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 17 with the time t from the blowing start time as the horizontal axis. It is a thing. In the figure, “KS-1” and “KS-2” indicate differences in blowing conditions.

  Further, FIG. 9 shows the spectral radiant light intensity ratio R between specific wavelengths (1020 nm and 720 nm, 920 nm and 720 nm, 650 nm and 720 nm) of the emitted light from the fire point 5 measured by the spectroscopic sensor 17. The time t from the start time is shown on the horizontal axis.

  8 and 9 show the actual component ratio of silicon Si and carbon C in the hot metal 2 by sampling the hot metal 2 in the furnace body 1 at each time t from the start time of blowing. The measurement results are also shown.

FIG. 3B shows a temporal change in the spectral radiant light luminances P ₁ and P ₂ of a pair of specific wavelengths λ ₁ and λ ₂ having remarkable time characteristics, and spectral radiation between the specific wavelengths λ ₁ and λ _2. The schematic diagram of the time change of the light luminance ratio R (= P ₁ / P ₂ ) and the time change of the actual component ratio of silicon Si is shown.

  That is, before the start of blowing, no hot spot is generated in front of the lance (downward), but high-temperature hot metal is present in front of the lance, so that the light emitted from the hot metal is observed at the receiver.

  When blowing (acid feeding) is started, a fire point is generated by oxygen blown from the lance to the hot metal, and the silicon component ratio in the hot metal is reduced by desiliconization reaction at the hot point part. At this time, the light receiver detects the emitted light from the fire point simultaneously with the generation of the fire point, and an increase in the spectral radiant light luminance ratio R is observed with the progress of blowing (decrease in the silicon component).

  As blowing proceeds and the desiliconization reaction proceeds, the spectral radiant light intensity ratio R further increases, but at a certain point after the start of blowing, the spectral radiant light intensity ratio R shows 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.

  And the signal processing apparatus 22 monitors the time change of the spectral radiant light luminance ratio R of the radiated light which a fire point emits from the blowing start time, and detects completion | finish of a desiliconization reaction.

FIG. 6 is a flowchart showing the above-described detection operation of the signal processing unit 22.
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 Q1). 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 (Q2), among the spectral radiant brightness P of each wavelength input from the spectroscopic measurement sensor 17, the predetermined specific wavelengths λ ₁ and λ ₂ are determined. Spectral radiation brightness P ₁ and P ₂ are read (Q3). Next, the spectral radiant light luminance ratio R (= P ₁ / P ₂ ) between the specific wavelengths is calculated (Q4). A moving average between the radiant light luminance ratio R calculated this time and the radiant light luminance ratio R previously calculated last time is calculated, and this moving average is newly set as the current radiant light luminance ratio R (Q5).

Then, a difference ΔR between the current radiant light luminance ratio R and the moving average of the previous radiant light luminance ratio R is calculated (Q6). When the difference ΔR is less than a predetermined value Ra (Q7), when the difference ΔR exceeds a predetermined value Rb (where Ra> Rb) (Q8), or when the difference ΔR is a predetermined value If it is equal to or less than Rb (Q8) and the change flag remains 0 (Q9), the process returns to Q2, and each wavelength input from the spectroscopic sensor 17 after the unit time (sampling time) Δt has elapsed. spectral of the emitted light intensity P, a specific wavelength lambda ₁ predetermined, read the spectral emission light luminance P _1, P ₂ of λ ₂ (Q3).

  If the difference ΔR between the current radiant light intensity ratio R and the moving average of the previous (or any number of times before) radiant light intensity ratio R is greater than a predetermined value Ra (Q7), a fire point is generated. Then, it is determined that the desiliconization reaction has started, a reaction start signal is output (Q10), the change flag is set to 1 (Q11), and the process returns to Q2.

  When the difference ΔR is equal to or less than the specified value Rb (Q8) and the change flag is set to 1 (Q9), it is determined that the silicon Si component ratio has reached the target component ratio, and the desiliconization reaction An end signal is output (S12), and the change flag is cleared to 0 (S13). 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 (S14).

In the fire point radiation measuring method of the second embodiment configured as described above, the radiant light intensity ratio R (= P) of the spectral radiant light intensities P ₁ and P ₂ between the wavelengths λ ₁ and λ _{2 that} are greatly different in time. ₁ / P ₂ ) is calculated, and it is detected that the desiliconization reaction of the hot metal 2 has been completed from the time t change from the blowing start time of the radiant light luminance ratio R.

  Therefore, even if the level of the incident light from the tip of the lance 3 fluctuates greatly due to the disturbance factor, the influence of the light amount fluctuation due to the disturbance factor is suppressed, and only the fluctuation of the radiated light itself from the fire point 5 is detected. It becomes possible to more stably measure changes in the components of the hot metal 2.

  In the above-described hot spot radiation measuring method of the second 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 ratio R and the time change characteristic of the component ratio in FIG. 3B to the time change characteristics corresponding to the carbon C, respectively.

The present invention is not limited to the second embodiment described above.
The signal processing device 22 reads the spectral radiant luminances P ₁ and P ₂ of the predetermined specific wavelengths λ ₁ and λ ₂ among the spectral radiant luminances P of the respective wavelengths input from the spectroscopic measurement sensor 17, and The change in the component ratio (concentration) of silicon Si and carbon C in the hot metal 2 and the target component ratio from the respective time change characteristics from the blowing start time in the two spectral radiant light intensities P ₁ and P ₂ It is also possible to detect.

Schematic diagram of a converter using a blowing process to which the hot spot radiation measuring method and the hot spot radiation measuring apparatus according to the first embodiment of the present invention are applied. Flow chart showing the operation of the hot spot radiation measurement method of the same embodiment Diagram for explaining the operating principle of the hot spot radiation measurement method 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 a second embodiment of the present invention are 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 Flow chart showing the operation of the hot spot radiation measurement method of the same embodiment The figure which shows the spectral characteristic (wavelength characteristic) of the synchrotron radiation measured with the hot spot radiation measuring method of the embodiment The figure which shows the spectral characteristic (time characteristic) of the synchrotron radiation measured with the hot spot radiation measuring method of the embodiment The figure which shows the spectral characteristic (time characteristic) of the synchrotron radiation similarly measured with the hot spot radiation measuring method of the same embodiment

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Furnace body, 2 ... Hot metal, 3 ... Lance, 4 ... Acid feed hole, 5 ... Fire point, 6 ... Branch pipe, 8 ... Oxygen, 12 ... Opening, 13 ... Measurement case, 14 ... Light receiver, 15 ... Communication Cable, 16, 22 ... signal processing device, 17 ... spectroscopic measurement sensor, 18 ... light diffusion plate, 19 ... linear wavelength distribution filter, 20 ... SSGC, 21 ... line light receiving sensor

Claims (8)

In the upper blowing process,
Measure 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 that performs acid feeding, through 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 radiant brightness. In the upper blowing process,
Measure the spectral radiant light intensity at a plurality of wavelengths of the emitted light emitted by the fire point generated below the acid feed hole at the lower end of the lance that performs the acid feeding through the lance,
A hot spot radiation measuring method, characterized in that a change in the hot metal component is detected from a time change of each spectral radiant light luminance at a plurality of wavelengths. In the upper blowing process,
Measure the spectral radiant light intensity at a plurality of wavelengths of the radiation emitted from the fire point generated below the acid feeding hole at the lower end of the lance that performs acid feeding through the lance,
Calculate the ratio of spectral radiant brightness between the multiple wavelengths,
A hot spot radiation measuring method, characterized in that a change in the hot metal component is detected from a temporal change in the ratio of the spectral radiant brightness between the plurality of wavelengths.   4. The spectral radiant light brightness at a plurality of wavelengths of 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. Fire point radiation measurement method.   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. 5. The hot spot radiation measuring method according to claim 4, wherein each spectral radiation light luminance at a plurality of wavelengths is measured. A light receiving means that is installed at an upper end opening of a lance that feeds acid from above a container that contains at least hot metal, and that measures the radiant brightness of emitted light emitted from a fire point generated below the acid feeding hole at the lower end of the lance; ,
A fire point radiation measuring apparatus comprising: signal processing means for inputting a radiant light intensity output from the light receiving means and detecting a change in a hot metal component based on a temporal change of the radiant light brightness. . At least at the upper end opening of the lance that feeds acid from above the container containing the hot metal, the spectral radiant brightness at a plurality of wavelengths of the emitted light emitted from the fire point generated below the feed hole at the lower end of the lance. Spectral light receiving means for measuring;
And a signal processing means for inputting the spectral radiant light intensity output from the spectral light receiving means and detecting a change in the hot metal component based on a temporal change in the spectral radiant light brightness. Fire point radiation measuring device.   8. The fire point radiation measuring apparatus according to claim 7, wherein the spectral light receiving means is a spectral measurement sensor including a linear wavelength distribution filter and a line light receiving sensor.

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