JP2002174631A - Component measuring device for molten metal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a component measuring device for molten metal capable of constantly providing a stable measuring plane irrespective of molten metal bulk conditions and accurately and quickly measuring components of a molten metal without contact by using the measuring plane. SOLUTION: This component measuring device is provided with a probe 10 dipped in the molten metal L and holding the molten metal inside, a measuring plane forming means 20 continuously feeding gas of a pressure higher than atmospheric pressure from above toward a surface of the molten metal L inside the probe 10, discharging the gas outside the probe, and forming the measuring plane on the surface of the molten metal inside the probe 10, and a measuring means 30 irradiating light containing a wavelength for component measurement on the measuring plane S through the probe 10 and measuring concentrations of predetermined components on the basis of reflected light.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a molten metal component measuring device for directly measuring a molten metal component.

[0002]

2. Description of the Related Art In converter blowing, oxidation refining mainly for decarburization is carried out by top blowing or bottom blowing oxygen. In recent years, the development of the hot metal pretreatment process has made it possible to dramatically reduce the amount of slag generated in converter blowing. This is because the dephosphorization step came to be performed in a pretreatment step before converter blowing, from a dephosphorization step in converter blowing which requires a large amount of slag. In converter blowing with a small amount of slag, it is possible to add a new function that is difficult under a large amount of slag, such as smelting reduction of Mn ore during blowing.

[0003] Mn is expensive after completion of blowing.
Although the adjustment was performed by adding a source, it goes without saying that if the Mn concentration can be increased by smelting reduction in such a furnace, a large rationalization will be achieved.

[0004] However, in the furnace reduction, it is difficult to grasp the reaction behavior with high accuracy during blowing, and high efficiency of the reaction and grasping of the components at the end point are major issues. That is, it is urgently necessary to grasp the component behavior during the reaction with high accuracy.

Conventionally, from the components before blowing and the blowing conditions,
Rough component estimation is performed using a component behavior estimation model during blowing. However, since highly accurate component estimation is extremely difficult, component adjustment by an expensive Mn source is ultimately indispensable through analysis after blowing and the like, and a considerable amount of an expensive Mn source is also necessary. The use of expensive Mn sources in large quantities results in an increase in cost, and inevitably prolongs the steelmaking time due to analysis and the like.

Here, if it is possible to appropriately know the molten steel component during blowing without contact, it becomes possible to perform dynamic control for adjusting the component at the end point of blowing, thereby greatly improving the precision of component control. be able to. And, quick component measurement before and after blowing leads to higher efficiency such as shortening of steel making time.

Various non-contact measurement methods using a laser or the like have been proposed as methods for quickly measuring components in a molten metal such as molten steel. Above all, those that irradiate a molten metal surface with a laser and measure its components are mainly used.

For example, Japanese Patent Application Laid-Open No. Sho 60-42644 discloses a method for measuring a molten metal component by emission spectroscopy utilizing gas injection. The measurement method described in this publication attempts to perform measurement using the interface between the gas and the molten metal generated at the time of gas injection.However, the disturbance of the interface due to gas bubbling is large, and the adhesion of iron near the tuyere There are also many problems such as tuyere blockage, and a stable measurement surface cannot be easily obtained. In addition, due to the characteristics of the laser measurement method, it is necessary to install the laser emission / reception unit near the interface. There are problems such as the durability of the device with respect to installation in a room. in this way,
An important point of this technique is how to easily obtain a stable measurement interface.

As an apparatus capable of obtaining a stable measurement surface, for example, an apparatus using a consumable probe of a sublance disclosed in Japanese Patent Application Laid-Open No. 61-181946 is known. In the technology disclosed in this publication,
The molten metal is introduced into the probe to obtain a measurement surface, and the measurement surface is irradiated with laser light, and the reflected light is detected to measure the components in the molten steel. However, in this technique, since the molten metal is introduced in an open-to-atmosphere state, the level of the molten metal in the probe, such as the level of the molten metal and the fluctuation of the molten metal, depends on the state of the molten metal. In other words, the use of a probe can prevent the influence of the disturbance of the molten metal surface to some extent, but if there is large turbulence in the bulk or the position of the liquid level changes significantly, a stable and It cannot be obtained and the measurement involves difficulty.

As described above, in the technique of sampling the molten metal in the probe and measuring its component, it is important how to obtain a sufficiently stable measurement surface. The technology for obtaining a sufficiently stable measurement surface has not yet been established.

[0011]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and it is possible to always obtain a stable measurement surface regardless of the molten metal bulk conditions. Accordingly, it is an object of the present invention to provide a molten metal component measuring device capable of measuring a component of a molten metal with high accuracy and speed.

[0012]

According to a first aspect of the present invention, there is provided a probe immersed in a molten metal and holding a molten metal therein, the probe being directed upwardly toward a surface of the molten metal in the probe. And a gas having a pressure higher than the atmospheric pressure is continuously supplied and discharged outside the probe, and a measurement surface forming means for forming a measurement surface on the surface of the molten metal in the probe, and light including a wavelength for component measurement is provided. A measuring device for irradiating the measurement surface through a probe and measuring the concentration of a predetermined component based on the reflected light is provided.

As described above, the high-pressure gas is supplied to the surface of the molten metal in the probe immersed in the molten metal, and the gas is discharged in the vicinity of the molten metal, whereby the molten metal or the surface under the strong stirring is supplied. A stable molten metal surface can be easily obtained even in a molten metal where a large disturbance exists, and by applying the non-contact measuring means by light irradiation using the molten metal surface as a measurement surface. ,
Highly accurate and quick measurement of molten metal components can be realized.

In this case, the probe has a bottomed cylindrical shape and is provided on a side surface thereof with a sampling hole for sampling molten metal, and the probe constitutes the measuring surface forming means and is provided above the sampling hole. Having a gas discharge hole, and in a state where the probe is immersed in the molten metal to a position equal to or more than the upper edge of the gas discharge hole, the surface of the molten metal sampled from the sampling hole and held by the probe is The measurement surface may be formed by continuously supplying gas and discharging the gas from the gas discharge hole. As described above, by using the bottomed cylindrical probe, the molten metal can be intermittently sampled and the component can be intermittently measured.
Further, the sampling hole and the gas discharge hole may be formed integrally, in which case the molten metal is sampled from the lower side of the hole, and the gas is discharged from the upper side. , Can perform the above functions. Further, it is preferable to further have a temperature measuring means for measuring the temperature of the molten metal, and when measuring a predetermined component of the molten metal by the measuring means using the measuring surface, radiation light radiated from the measuring surface Is further provided with a radiation light measuring means for measuring the temperature of the molten metal measured by the radiation light measuring means and the temperature of the molten metal measured by the temperature measuring means. Is preferably determined.

[0015] The probe may be formed in a cylindrical shape having an open bottom for introducing molten metal. Thereby, the molten metal can be continuously taken into the probe and the component can be continuously measured.

In this case, there is provided a gas discharge hole provided on a side surface of the probe and constituting the measurement surface forming means, and the probe is immersed in the molten metal to a position at or above the upper edge of the gas discharge hole. The state may be configured such that the measurement surface is formed by supplying the gas to the surface of the molten metal held in the probe and discharging the gas from the gas discharge hole, or the probe The measuring surface may be formed by supplying the gas to the surface of the molten metal held therein and discharging the gas from the opening at the bottom.

According to a second aspect of the present invention, there is provided a probe having a bottomless cylindrical shape and disposed above a surface of a molten metal, and a gas having a pressure higher than an atmospheric pressure from above toward the surface of the molten metal via the probe. Is continuously supplied, and a measurement surface forming means for forming a measurement surface on the surface of the molten metal, and irradiating the measurement surface with light including a wavelength for component measurement through the probe,
A measuring device for measuring the concentration of a predetermined component based on the reflected light is provided.

As described above, by continuously supplying a high-pressure gas to the surface of the molten metal through the probe disposed above the surface of the molten metal, a large disturbance exists in the molten metal or the surface under strong stirring. A stable molten metal surface can be easily obtained even with such molten metal, and by using the molten metal surface as a measurement surface and applying non-contact measuring means by light irradiation, the component measurement of the molten metal can be performed. Can be performed with high accuracy, quickly and continuously.

Further, a third invention provides a nozzle provided on a side wall or a bottom wall of a container holding a molten metal so that a nozzle hole is connected to the molten metal in the container, and a nozzle provided to the molten metal through the nozzle. A gas having a pressure higher than the atmospheric pressure is continuously supplied toward the measurement surface forming means for forming a measurement surface on the gas supply portion of the molten metal, and light containing a wavelength for component measurement is supplied to the measurement surface through the probe. A measuring device for irradiating and measuring the concentration of a predetermined component based on the reflected light is provided.

As described above, a nozzle is provided on the side wall or the bottom wall of the container holding the molten metal so as to be continuous with the molten metal in the container, and a pressure higher than the atmospheric pressure is applied to the molten metal through the nozzle. By continuously supplying gas,
Regardless of the molten metal under strong stirring or the molten metal whose surface has a large disturbance, a stable measurement surface can be easily obtained regardless of that, and non-contact measurement by light irradiation using the measurement surface By applying the means, it becomes possible to measure the components of the molten metal with high accuracy, quickly and continuously.

In any one of the above inventions, the measuring means may include a light emitting unit that emits light including a wavelength for component measurement, a light quantity of light reflected on the measurement surface, and the predetermined amount based on the detection result. A measuring unit for determining the concentration of the component, a tip optical system provided in or near the probe, for irradiating light from the light emitting unit to the measurement surface and receiving light reflected by the measurement surface, and the light emitting unit And an optical fiber for guiding light between the tip optical system and between the tip optical system and the measurement unit.

The light is preferably a laser light,
In this case, the light-emitting unit is configured such that the laser light source for the measurement component, the laser light source for the main component of the molten metal, the laser light source for the reference light having no light absorption, and the laser light from these light sources on the same optical path. And a guiding optical system. In the second and third aspects of the present invention, it is preferable that the apparatus further includes a temperature measuring means for measuring the temperature of the molten metal.

[0023]

Embodiments of the present invention will be specifically described below with reference to the accompanying drawings. (First Embodiment) FIG. 1 is a schematic view showing a molten metal component measuring apparatus according to a first embodiment of the present invention. This molten metal component measuring apparatus is used for measuring the component of molten metal, for example, molten steel, and has a bottomed cylindrical probe 1 immersed in molten metal L and holding molten metal L therein.
0, a measurement surface forming means 20 for forming a measurement surface S on the surface of the molten metal therein, and irradiating the measurement surface S with a laser beam through the probe 10 and measuring the concentration of a predetermined component based on the reflected light. Measuring means 30.

A sampling hole 11 for sampling a molten metal (molten steel) is provided on a lower side surface of the probe 10. Above the sampling hole 11, a gas discharge hole 12 is provided. The portion below the gas discharge hole 12 of the probe 10 is a sampling chamber 13 in which the molten metal is sampled and held. A vapor layer 17 is formed on the measurement surface S of the molten metal L in the sampling chamber 13. In this figure, one sampling hole 11 and two gas discharge holes 12 are provided, but the number is not limited to this. Although the sampling hole and the gas discharge hole are provided separately, the sampling hole and the gas discharge hole are integrated, and the upper part thereof is a gas discharge hole,
The lower part may be used as a sampling hole. In addition, the upper part of the probe 10 is externally fitted and held by a probe holder 14 fixed to a sublance 15. A temperature sensor 16 is provided below the bottom of the probe 10.

Further, the probe 10 has a gas introduction mechanism 21 for introducing a gas having a pressure higher than the atmospheric pressure into the probe 10.
By introducing an appropriate gas into the probe 10 from the gas introduction mechanism 21 via a pipe (not shown), supplying the gas to the surface of the molten metal in the probe 10 and discharging the gas from the gas discharge hole 12, the molten metal Measurement surface S on the surface
Is formed. That is, the measurement surface forming means 20 is constituted by the gas introduction mechanism 21 and the gas discharge holes 12. As the gas to be introduced, an inert gas such as Ar or N 2
Those having low reactivity with molten metal such as ₂ are preferred.

The measuring means 30 includes a light emitting section 31 for emitting a laser beam for measurement, and a measuring means for detecting the amount of light reflected on the measuring surface S and obtaining the concentration of a predetermined component based on the detection result. Part 32 and probe holder 1
4 is provided in the probe 10 in a state attached to
A tip optical system 33 for irradiating the measurement surface S with laser light from the light emitting unit 31 and receiving light reflected by the measurement surface S, and between the light emitting unit 31 and the tip optical system 33 and between the tip optical system 33
And first and second optical fibers 34 and 35 for guiding light between the first and second measuring units 32.

The light emitting section 31 includes a first laser light source 41a that emits a laser beam (absorbed light) for a measurement component, and a second laser that emits a laser beam (a main component absorbed light) for a main component of the molten metal. It has a light source 41b and a third laser light source 41c that emits a reference laser beam (reference beam). Laser beams from these laser light sources are sampled by a laser beam sampler 42, respectively, guided to a photodetector 43 and a wavelength detector 44, and the light intensity and the wavelength are detected. Also,
The light emitting section 31 has an optical system 45, and these laser beams are applied to an optical filter (high-pass filter) 4 therein.
6 to the same optical path, and through a lens 47 to the first optical fiber 34. It should be noted that immediately before the laser beam enters the first optical fiber 34, the chopper 48
Are arranged, and the radiated light can be measured.

The tip optical system 33 includes the probe holder 14
And a lens 49 for irradiating the laser light guided to the first optical fiber 34 to the measurement surface S of the molten metal L in the sampling chamber 13, and transmitting the reflected light from the measurement surface S to the second surface. The optical fiber 35 is guided.
The optical fiber 35 penetrates the lens 49 so as to receive the reflected light without passing through the lens 49. As the optical system that constitutes the tip optical system 33, another optical system that can project the measurement light onto the measurement surface and receive the reflected light may be arranged. As described above, by holding the distal end optical system 33 on the probe holder 14 so as to be separable from the probe 10, the probe 10 can be easily made consumable. Therefore, it can be handled in the same manner as a conventional sublance probe, which is practically advantageous.

The measuring section 32 includes a lens 50 for converting the light emitted from the second optical fiber 35 into parallel light, and a lens 50 as described above.
An optical filter (high-pass filter) 51 that splits laser light obtained by combining laser light from the two laser light sources 41a, 41b, and 41c into a narrow wavelength range including each laser wavelength, and detection from the split light in three wavelength ranges. A band-pass filter 52 for extracting components in a wavelength range necessary for the above, a first photodetector 53a for detecting the light intensity of the absorbed light, the main component absorbed light, and the reference light, respectively, and a second light detection. It has a detector 53b, a third photodetector 53c, and a computer 54 for calculating the concentration of a predetermined component of the molten metal based on the light intensity detected by them. The computer 54 stores temperature information from the temperature sensor 16, laser wavelength information from the wavelength detector 44, and the light detector 43.
The laser output power information measured in step (1) is also input, and the computer 54 uses the information to correct laser power fluctuation, laser output wavelength fluctuation, radiation light correction, thickness fluctuation of the vapor layer 17, temperature correction, Can be corrected.

As the probe 10, a probe mainly made of paper, such as a consumable probe of a converter usually used, is low in cost and easy to use. Further, when applied to molten steel in a converter, not only the temperature sensor 16 for temperature measurement but also a carbon determinator (CD) for carbon concentration measurement
By combining the functions of a sublance used in a conventional converter, such as an oxygen measuring device and an oxygen measuring device, it is possible to measure a predetermined component, for example, Mn in molten steel, without hindering the operation of the conventional converter.

Further, since the molten metal sampled and held by the probe 10 is subjected to component measurement in a molten state, it is necessary to keep the molten metal in a molten state. It is preferable to be composed of a highly heat-insulating material. Further, the probe 10
Is formed of a consumable material such as paper to form a consumable probe, which may cause trouble in the measurement due to smoke in the probe 10 during measurement. It can be avoided by taking measures such as applying refractories.

In actual use, when the molten metal rapidly flows into the probe 10, or when molten steel is used, a rapid decarburization reaction may occur. In such a case, the molten metal (molten steel) may be scattered and greatly affect the entire measurement system. However, as a countermeasure, a molten metal such as quartz is placed between the tip optical system 33 and the measurement surface S. It is effective to provide a shielding plate that transmits at least a part of the light necessary for the component measurement. In the case of molten steel, it is also effective to put a deoxidizing material such as Al or Si in the sampling chamber 13 or the like in advance. Further, the gas flow rate to be introduced is partially or entirely reduced by 10
When the speed was maintained at m / s or more, the adverse effect on the measurement system due to the scattering of molten steel during the decarburization reaction or the like could be significantly reduced.

Next, the component measuring operation in the molten metal component measuring apparatus configured as described above will be described.
First, a gas (for example, Ar, N ₂ ) having a pressure higher than the atmospheric pressure is introduced into the probe 10 from the gas introduction mechanism 21 of the measurement surface forming means 20 described above, and discharged from the sampling hole 11 and the gas discharge hole 12.

In this state, the probe 10 is connected to the gas exhaust hole 12.
Immersed in the molten metal (molten steel) L up to the upper edge or more.
That is, the gas is immersed to a depth at which the gas discharge holes 12 are completely immersed. When the probe 10 is immersed in this manner, the molten metal (molten steel) L enters through the sampling hole 11 and fills the sampling chamber 13 in the probe 10. The gas is forcibly discharged and bubbled from the gas discharge holes 12 by introducing the gas at a pressure sufficiently higher than the static pressure of the gas. By this action, no matter what disturbance is present on the surface of the molten metal bulk, and no matter what depth the probe 10 is immersed in, the gas exhaust hole 12
A stable molten metal surface is formed immediately below the surface. Therefore, by using this as the measurement surface S, stable component measurement, for example, Mn measurement can always be performed by a non-contact type component measurement method of irradiating a laser beam.

The immersion depth of the probe 10 is
The position just above 2 is sufficient, but if there is a large disturbance on the surface of the bulk molten metal, the molten metal level fluctuates so strongly that it is necessary to immerse the metal to a sufficient depth. In the case of converter blowing, immersion of about 300 to 1000 mm above the gas discharge hole 12 is appropriate.

However, since the surface of the bulk molten metal is greatly disturbed and the surface level fluctuates greatly, the molten metal is introduced into the sampling chamber 13 when the level rises due to the level fluctuation, but the level falls. When molten metal is in sampling chamber 1
When there is a case where the introduction of the molten metal into the sampling chamber 13 becomes insufficient, such as when the molten metal is not introduced into the sample 3, the radiation emitted from the surface of the molten metal is measured by a radiation light measuring device (not shown), and its intensity and By comparing the temperature measured by the temperature sensor 16 with the relational expression obtained in advance, it is possible to determine whether the state of introducing the molten metal is good or bad. If the introduction of the molten metal into the sampling chamber 13 is incomplete,
Since the introduced molten metal is rapidly cooled in the sampling chamber 13, the intensity of the radiated light radiated at the temperature of the molten metal at the time of forming the normal molten metal becomes a small value. It is possible to determine the relationship between the molten metal temperature at the time and the radiant light intensity and determine the introduction state of the molten metal, that is, the quality of the measurement surface, by measuring the radiant light intensity at the time of measurement and comparing it with a relational expression obtained in advance. it can.

It should be noted that gas introduction into the probe 10 is basically unnecessary when measurement is not performed. However, in the case where disturbance such as scattering of molten metal or dust exists, it is necessary to prevent foreign matter from entering the probe 10. It is desirable that the gas be constantly introduced into the probe 10 and discharged from the gas discharge hole 12 or the like. In particular, during normal blowing in a converter,
Foreign matter such as scattering of granular iron, dust and high-temperature gas
This is effective because there is a possibility of intrusion into 0. At this time, the probe 10 and the probe holder 1
4 is not required to be completely sealed, but if the degree of sealing is low, the introduced gas is blown out of these joints by the static pressure of the molten steel when the probe 10 is immersed, and the appropriate It is preferable to make the degree of sealing high, since no bubbling is performed.

In this embodiment, the stable measurement surface S formed as described above is irradiated with laser light,
The components are measured by the atomic absorption method. That is, the light emitting unit 3
1st first to third laser light sources 41a, 41b, 41
From c, the absorption light corresponding to the measurement component (for example, Mn in molten steel), the absorption light of the main component corresponding to the main component (Fe in the case of molten steel), and the reference light are converted into the first optical fiber 34 and the tip optical system 33. Is applied to the measurement surface S in the sampling chamber 13 of the probe 10 through the same optical path. At this time, since the light passes through the vapor layer 17 on the molten metal L, the light intensity of the absorbed light and the main component absorbed light changes according to the concentration of the measurement component in the vapor layer 17. Then, these laser beams after passing through the vapor layer 17 reach the measuring unit 32 through the tip optical system 33 and the second optical fiber 35. In the measuring section 32, the laser light is separated into the original three components by the optical filter 51, and the first to third photodetectors 53a, 53b,
53c detects these intensities, and the computer 54 calculates the concentration of the measurement component, for example, Mn based on the detected intensities. Then, by obtaining in advance the relational expression (calibration curve) between the absorbance of the measured element and the concentration of the measured element in the molten metal, which has been corrected by the computer 54 as described above, highly accurate measurement is possible. In this case, regarding the correction at this time, the correction of the laser power can be performed by the ratio between the power at the time of obtaining this relational expression (calibration curve) and the power at the time of measurement. In addition, since the degree of light absorption of the measurement element changes when the laser output wavelength changes, a relational expression of the degree of light absorption of the measurement element with respect to the change of the laser output wavelength is obtained in advance, and the laser output wavelength is measured. The degree of light absorption can be corrected.
For the correction of the radiated light, the radiated light intensity when cut off by the chopper 48 is obtained in a time series. To determine the true reflected light intensity.
The thickness of the vapor layer 17 was corrected by taking the absorbance ratio of the measurement element and the main component element. In addition, the temperature correction
Using the literature on the temperature change of the vapor pressure, in the case of molten steel, for example, it can be corrected by standardizing to the values of the absorbance of the measured component and the main component at the vapor pressure of 1600 ° C.

As shown in FIG. 2, the molten metal component measuring apparatus according to the present embodiment can be applied to, for example, a sub-lance 80 provided on a side of a main lance 70 for acid supply in a converter 60. . The probe 10 is provided at the tip of the sub-lance 80 via the probe holder 14, the probe 10 is immersed in the molten steel L in the converter, and the molten steel L is sampled in the probe 10. Then, by supplying gas to the sampled molten metal from the gas introduction mechanism 21 via the pipe 22 as described above, a stable measurement surface S is formed in the probe 10. Then, as described above, a predetermined component in the molten steel is directly measured by a non-contact measurement method using a laser beam. Reference numeral 61 denotes a tuyere for bottom blowing, and 62 denotes a gas pipe.

In this way, the composition of the molten metal (molten steel) can be measured directly and in real time by a non-contact measurement method. Sampling and component measurement by such a probe can be performed intermittently and repetitively, and therefore, a temporal change of a predetermined component can be easily grasped in real time.

(Second Embodiment) FIG. 3 is a schematic view showing a molten metal component measuring apparatus according to a second embodiment of the present invention. The molten metal component measuring device of the present embodiment has the same configuration as that of the first embodiment except that a cylindrical probe 10a having an opening 18 for introducing molten metal is formed at the bottom. Therefore, the same members as those in the first embodiment are denoted by the same reference numerals, and the description is simplified.

In this embodiment, when the probe 10a is immersed in the molten metal L, the molten metal L
Is introduced into the probe 10a. Then, the probe 10a is connected from the gas introduction mechanism 21 through a pipe (not shown).
By introducing an appropriate gas having a pressure higher than the atmospheric pressure into the inside of the probe, supplying the gas to the surface of the molten metal in the probe 10a and discharging the gas from the gas discharge hole 12, the measurement surface S is formed on the surface of the molten metal. You. In this case, the molten metal L is introduced from the bottom opening 18 when the probe 10a is immersed in the molten metal L, so that the components of the molten metal can be continuously measured. Note that the gas discharge hole 12 does not have to be provided, in which case the gas from the gas introduction mechanism 21 is discharged from the bottom opening 18 and a measurement surface is formed on the bottom of the probe 10a.

In the present embodiment, the probe 10a is made of a refractory material such as BN (boron nitride) in order to enable continuous use of the probe 10a in consideration of continuous measurement of components. Is preferred.

Next, the operation of measuring the components of the molten metal in this embodiment will be described. Also in the present embodiment, first, a gas (for example, Ar, N ₂ ) having a pressure higher than the atmospheric pressure is introduced into the probe 10 a from the gas introduction mechanism 21 of the above-described measurement surface forming means 20 and discharged from the gas discharge hole 12. .

In this state, the probe 10a is immersed in the molten metal (molten steel) L. The immersion is performed to a depth at which the gas discharge holes 12 are completely immersed. By immersing the probe 10a in this way, the molten metal (molten steel) L is
From the gas introduction mechanism 21
Gas is introduced into the molten metal surface at a pressure well above the static pressure of the molten metal from the
It is forcibly discharged and bubbled from 2. Due to this action, a stable molten metal surface is formed immediately below the gas discharge hole 12 of the probe 10a regardless of any disturbance on the surface of the molten metal bulk or immersion of the probe 10a at any depth. Is done. Therefore, by using this as the measurement surface S, stable component measurement, for example, Mn measurement can always be performed by a non-contact type component measurement method of irradiating a laser beam.

In this way, the component measurement of the molten metal (molten steel) can be performed directly and in real time by a non-contact measurement method. Since the molten metal can be continuously introduced from the opening 18 at the bottom by immersing the probe 10a in this manner, the component measurement can be continuously performed, and therefore, the change with time of the predetermined component can be performed. Can be grasped easily and in real time, and the concentration of the component of the molten metal can be grasped more accurately than in the case of the first embodiment. In addition, the component measuring device of this embodiment can also be applied to the component measurement of molten steel at the time of converter blowing shown in FIG.

(Third Embodiment) FIG. 4 is a schematic view showing a molten metal component measuring apparatus according to a third embodiment of the present invention. The molten metal component measuring device of the present embodiment is configured in the same manner as the first embodiment except that a cylindrical non-contact type probe 10b having an opening 19 formed at the bottom is used. Therefore, the same members as those in the first embodiment are denoted by the same reference numerals, and the description is simplified.

In this embodiment, the probe 10b is positioned above the molten metal L without being immersed in the molten metal L.
A suitable gas having a pressure higher than the atmospheric pressure is introduced into the inside, and this gas is supplied to the surface of the molten metal. Thereby, the measurement surface S is formed on the surface of the molten metal. In this case, since the measurement surface S is formed directly on the surface of the molten metal in the container without sampling the molten metal L, the components of the molten metal can be continuously measured.

In this embodiment, since the probe 10b is not immersed in the molten metal, the life of the probe 10b is long,
Suitable for continuous component measurement. Probe 1
In order to make 0b suitable for continuous use, for example, BN
The probe 10b is preferably made of a refractory such as (boron nitride).

Next, the components of the molten metal in the present embodiment
The measurement operation will be described. In the present embodiment,
The lobe 10b is immersed in the molten metal L above the molten metal L.
Arrange so that it is not pickled. And the above measurement surface shape
From the gas introduction mechanism 21 of the forming means 20 into the probe 10b.
Gases having a pressure higher than the atmospheric pressure (for example, Ar, N ₂)
Then, it is supplied to the molten metal surface through the opening 19 at the bottom.

By supplying the gas from the gas introduction mechanism 21 toward the surface of the molten metal at a pressure sufficiently higher than the static pressure of the molten metal, even if there is any disturbance on the surface of the molten metal bulk, the gas can be stabilized by the pressure of the gas. A molten metal surface is formed. Therefore, by using this as the measurement surface S, stable component measurement, for example, Mn measurement can always be performed by a non-contact type component measurement method of irradiating a laser beam.

In this way, the component measurement of the molten metal (molten steel) can be performed directly and in real time by a non-contact measurement method. Then, instead of sampling the molten metal, the molten metal is irradiated with laser light from above the molten metal, so that continuous component measurement is possible by continuously irradiating the laser light, Not only can the change with time of the component be easily and in real time be grasped, but also the concentration of the component of the molten metal can be grasped more accurately than in the case of the first embodiment. In addition, the component measuring device of this embodiment can be applied to the component measurement of molten steel at the time of converter blowing in FIG. 5 is the same as FIG. 2 except that a non-contact probe 10b is used for the molten metal.

(Fourth Embodiment) FIG. 6 is a schematic view showing a molten metal component measuring apparatus according to a fourth embodiment of the present invention. The molten metal component measuring apparatus of the present embodiment is different from the first embodiment in that a nozzle 90 having a nozzle hole continuous with the molten metal in the container is provided on the side wall of the molten metal container 91 instead of the probe. To the third embodiment. Therefore, the same members as those of the first to third embodiments are denoted by the same reference numerals, and the description will be simplified.

In this embodiment, the tip optical system 33 is provided in the nozzle 90, and an appropriate gas is supplied from the gas introducing mechanism 21 into the nozzle 90 and discharged into the molten metal L. Thereby, the measurement surface S is formed at the interface between the molten metal L and the nozzle hole. In this case, since the measurement surface S is directly formed at the interface between the molten metal L and the nozzle hole in the molten metal container 91 without sampling the molten metal L, it is necessary to continuously measure the components of the molten metal. Can be. The nozzle may be provided at the bottom of the molten metal container 91.

In order to make the nozzle 90 suitable for continuous use, it is preferable to form the nozzle 90 from a refractory such as BN (boron nitride).

Next, the operation of measuring the components of the molten metal in this embodiment will be described. In the present embodiment, the nozzle 90 is provided on the side wall of the molten metal container 91 and the nozzle hole is connected to the molten metal L. Then, a gas having a pressure higher than the atmospheric pressure (for example, Ar or Ar) is introduced into the nozzle 90 from the gas introduction mechanism 21 of the measurement surface forming means 20 described above.
N ₂ ) is introduced and supplied to the molten metal L.

By supplying gas from the gas introduction mechanism 21 toward the molten metal L at a pressure sufficiently higher than the static pressure of the molten metal, even if any disturbance exists in the molten metal bulk,
A stable molten metal interface is formed by the pressure of the gas, and the gas is discharged into the molten metal L. Therefore, by using this interface as the measurement surface S, stable component measurement, for example, Mn measurement, can be always performed by a non-contact type component measurement method in which laser light is irradiated.

As described above, the component measurement of the molten metal (molten steel) can be performed directly and in real time by a non-contact measuring method. Then, instead of sampling the molten metal, a nozzle 90 is provided on the side of the molten metal container 91,
Since the laser beam is applied to the molten metal through the nozzle 90, continuous component measurement is possible by continuously applying the laser beam. Therefore, not only the change with time of the predetermined component can be grasped easily and in real time, but also the concentration of the component of the molten metal can be grasped more accurately than in the first embodiment.

As shown in FIG. 7, the molten metal component measuring apparatus according to the present embodiment can be applied to, for example, a nozzle constituting a gas pipe 62 of a tuyere 61 for bottom blowing in a converter 60. That is, if gas is blown from the gas introduction mechanism 21 into the nozzles constituting the gas pipe 62 to form a measurement surface, the predetermined component in the molten steel is directly measured by the non-contact measurement method using laser light as described above. .

In the first to fourth embodiments,
An example in which a component is measured by an atomic absorption method by irradiating a laser beam has been described. That is, when the irradiated laser light irradiates the molten metal L in the sampling chamber 13 of the probe 10, it passes through the vapor layer 17 on the molten metal L. It can be carried out. However, the present invention is not limited to such a method as long as the method is a non-contact measurement method by irradiating light. Specifically, the light source is not limited to a laser. The type of the object to be measured is not limited as long as it is a molten metal, and the component to be measured is not limited to Mn, but may be any type, and a plurality of components can be measured simultaneously. Further, in the above embodiment, the light from the plurality of light sources is guided to the same optical path, and the light reflected by the molten metal is also guided to the same optical path. In that case, a plurality of optical fibers can be used in a bundle.

[0061]

EXAMPLES (Example 1) Here, an example of the first embodiment will be described. About 250 tons of hot metal was charged into a 250-ton capacity top-bottom blow composite blowing converter, and decarburization blowing was mainly performed to conduct a component measurement test. As the hot metal, pretreated hot metal subjected to desulfurization treatment and dephosphorization treatment in a hot metal pretreatment facility, which is a process prior to the converter, was used. Flux was added to the furnace to generate a small amount of slag, and argon or nitrogen was blown at about 10 Nm ³ per minute from the gas pipe and tuyere for the purpose of stirring the molten metal. In addition, the top blowing acid transfer rate from the lance (5 holes) charged into the converter from above was 60,000 Nm ^{3 /} h from the beginning to the middle of blowing,
It was controlled so that per hour 40000Nm ³ to blow the end. During blowing, Mn ore is charged appropriately, and M
The n concentration was increased.

As a measurement probe, a consumable sublance probe conventionally used in converter refining was modified and manufactured, and a probe having a structure substantially as shown in FIG. 1 was used. Both the sampling hole (1 hole) and the gas discharge hole (2 holes) have a hole diameter of 15 mm, and the inside hollow diameter of the probe is 30 m.
m. N ₂ was used as a gas to be introduced into the probe, and the flow rate was 400 to 800 NL / cm before and after immersion of the probe.
min.

A non-contact type laser measuring device was used for the component measurement, and the laser beam was used to excite a Ti sapphire laser with the second harmonic oscillation light (0.53 nm) of a YAG (yttrium-aluminum-garnet) laser. Then, a continuous wavelength laser beam was used, and the wavelength was adjusted for the second harmonic of the continuous wavelength laser beam to oscillate. As for the oscillation wavelength, the atomic absorption wavelength of Mn is around 403 nm,
Fe, the main component of molten steel, was around 386 nm, and the reference light was 4
Using a wavelength around 30 nm, the energy of the output laser light was 10 mW.

As the optical system, two optical fibers having a length of about 50 m (for laser input and laser reception) were used. One end of the laser light input fiber was disposed at a position where laser light from a laser light source was condensed, and the other end of the light input fiber was placed in a probe holder. In the probe, light emitted from the light-entering fiber passed through the vapor layer and was guided to the light-receiving fiber. The light emitted from the other end of the light receiving optical fiber is reflected by the lens as parallel light at 386 nm and 403 nm with respect to 45-degree incident light, and 430 nm.
The laser light is dispersed by an optical filter that transmits light at nm, and each laser light is further dispersed by an optical filter that reflects light at 386 nm and transmits light at 403 nm. Further, the light was guided to a photomultiplier tube (Hotmar) through a band-pass filter having a half-width of 2 nm and having the measurement wavelength as a central wavelength, and the intensity thereof was measured in units of 2 ms. The measurement is performed for 2 seconds and 1
000 data were collected.

The temperature is measured at a position below the bottom of the probe.
The measurement was performed using a t-Rh-based thermocouple. The cycle of the chopper was 100 msec, and the cutoff was 25 msec and the irradiation was 75 msec. The light intensity when cut off with a chopper is radiated light, and the average value of the radiated light intensity when cut off is calculated in time series.The radiated light intensity when measuring reflected light is the radiated light before and after the cutoff. More calculated. The true reflected light intensity was calculated by subtracting the calculated radiated light intensity. This was determined for each of the reference light and the absorbed light.

[0066] intensity ratio data of the absorbance, for the ratio of the measured intensity of reflected light absorbance and reference light (R) and absorption and reference light obtained while receiving a laser light without passing through the molten steel surface (R _O ) As a reference, the logarithm of the reciprocal of the ratio (−log
(R / R ₀ )) was taken as the absorbance. The absorbance of Fe, which is a main component element, was determined in the same manner.

The temperature of the molten steel is corrected using Mn, F at a steam pressure of 1600 ° C. using the literature value of the temperature change of the steam pressure.
Corrected and normalized to the absorbance value of e. To correct the vapor layer thickness, the absorbance ratio between Mn and Fe was calculated, and this absorbance ratio was defined as the Mn absorbance after the vapor layer thickness correction.

Using this apparatus, two measurements were performed at the end of blowing and after blowing. Immersion, measurement, sublance replacement, etc. were possible in the same operation as the conventional sublance. The component measurement was completed in about 5 seconds of immersion time, and was about 30 seconds including measurement, analysis, and calculation until the measured value was confirmed in the control room.

FIG. 8 shows the result of comparison between the measured value of Mn by the method of the present embodiment and the analyzed value by chemical analysis. FIG. 8 is a graph showing the relationship between the chemical analysis values of Mn on the horizontal axis and the measured values of Mn by the method of the present invention on the vertical axis. As is clear from FIG. 8, it was confirmed that the measured value of Mn according to the method of the present invention gave almost the same results as the chemical analysis values.

FIG. 9 shows the relationship between the temperature of the molten steel and the intensity of the radiated light when the radiated light from the measurement surface was measured at the same time as the Mn measurement. From the relational expression between the molten metal temperature and the radiant light intensity obtained in advance, the radiant light intensity was determined to be 90% as the determination value of the formation abnormality of the measurement surface. A low outlier was measured, at which time Mn
The measured value was also found to be an abnormal value, which was effective for determining the quality of the formation of the measurement surface by the radiation.

Since the measurement in this embodiment is for a short time,
The laser output wavelength was stable and did not change. Note that the laser output waveform changes in actual long-time measurement. Therefore, when the laser output wavelength changes, high-precision analysis can be performed by correcting the change in absorbance depending on the wavelength position.

(Example 2) Here, an example of the second embodiment will be described. In the same manner as in Example 1, about 250 tons of hot metal was charged into a 250-ton capacity top-bottom blow composite blowing converter, and decarburization blowing was mainly performed to conduct a component measurement test. As the hot metal, pretreated hot metal subjected to desulfurization treatment and dephosphorization treatment in a hot metal pretreatment facility, which is a process prior to the converter, was used. The furnace to produce a small amount of slag by the addition of flux was blown degree min 10 Nm ³ argon or nitrogen for the purpose of molten metal agitation from a gas pipe and a tuyere. A lance (5 holes) inserted into the converter from above
Per hour over the medium term on blowing oxygen-flow-rate from blowing early from 60000Nm ^3, per hour in the blow end 40000Nm ³
It controlled so that it might become. During blowing, Mn ore was appropriately charged to increase the Mn concentration by ore reduction.

As a probe for measurement, a consumable sublance probe conventionally used in converter refining was modified and manufactured, and a probe having a structure almost as shown in FIG. 3 was used. The bottom was opened for the inflow of molten steel, the gas discharge holes (two holes) were set to a hole diameter of 15 mm, and the internal hollow part diameter of the probe was set to 30 mm. The _{N 2} used as a gas to be introduced into the probe, the flow rate was controlled in the range of 400~800NL / min immersion before and after the probe. Durability is important for continuous measurement for several minutes.
N was used.

The measurement was carried out in the same manner as in Example 1 using the same laser beam as in Example 1. Further, correction of the temperature of the molten metal, correction of the vapor thickness, and the like were performed in the same manner as in Example 1.

Using the apparatus of this example, measurement was performed continuously (in units of 2 seconds) for 17 minutes from the start to the end of blowing. FIG.
Table 3 shows the measured values of Mn and the chemical analysis values of the metal sampled by the sublance in this example. In the figure, the solid line is the measured value of this example, and ○ is the chemical analysis value. As shown in this figure, the measured values of the present example almost coincided with the chemical analysis values. Since the measurement in this example was a short time, the laser output wavelength was stable and did not change.

Example 3 Here, an example of the third embodiment will be described. In the same manner as in Example 1, about 250 tons of hot metal was charged into a 250-ton capacity top-bottom blow composite blowing converter, and decarburization blowing was mainly performed to conduct a component measurement test. As the hot metal, pretreated hot metal subjected to desulfurization treatment and dephosphorization treatment in a hot metal pretreatment facility, which is a process prior to the converter, was used. Flux was added to the furnace to generate a small amount of slag, and argon or nitrogen was blown at about 10 Nm ³ per minute from the gas pipe and tuyere for the purpose of stirring the molten metal. A lance (5 holes) inserted into the converter from above
Per hour over the medium term on blowing oxygen-flow-rate from blowing early from 60000Nm ^3, per hour in blow end 40000Nm ³
It controlled so that it might become. During blowing, Mn ore was appropriately charged to increase the Mn concentration by ore reduction.

As a probe for measurement, a consumable type sublance probe conventionally used in converter refining was modified and manufactured, and a probe having a structure substantially as shown in FIG. 4 was used. The bottom was opened, and the internal hollow diameter of the probe was 30 mm.
The _{N 2} used as a gas to be introduced into the probe, the gas flow rate in the probe was controlled in the range of 400~800NL / min. In order to perform continuous measurement for several minutes, durability is important. Therefore, BN was used as a probe material.

For the measurement, the probe was placed above the molten metal, and the measurement was performed in the same manner as in Example 1 using the same laser beam as in Example 1. Further, correction of the temperature of the molten metal, correction of the vapor thickness, and the like were performed in the same manner as in Example 1.

Using the apparatus of this example, measurement was performed continuously (in units of 2 seconds) for 17 minutes from the start to the end of blowing. As a result, a result almost coincident with FIG. 10 was obtained, and almost coincided with the chemical analysis value of the metal sampled at the sublance. Since the measurement in this example was a short time, the laser output wavelength was stable and did not change.

(Example 4) Here, an example of the fourth embodiment will be described. In the same manner as in Example 1, about 250 tons of hot metal was charged into a 250-ton capacity top-bottom blow composite blowing converter, and decarburization blowing was mainly performed to conduct a component measurement test. As the hot metal, pretreated hot metal subjected to desulfurization treatment and dephosphorization treatment in a hot metal pretreatment facility, which is a process prior to the converter, was used. Flux was added into the furnace to generate a small amount of slag, and nitrogen gas was blown from the gas pipe and tuyere at a rate of about 10 Nm ³ per minute for the purpose of stirring the molten metal. At this time, the tip optical system was incorporated into one nozzle constituting the gas pipe, and the apparatus configuration was the same as that of FIG. Further, the lance which is charged from above the rolling furnace (5 holes) on blowing the oxygen-flow-rate per hour over to mid blowing early 60000Nm ³ from,
It was controlled so that per hour 40000Nm ³ to blow the end. During blowing, Mn ore is charged appropriately, and M
The n concentration was increased.

The measurement was carried out using the measurement surface formed in the nozzle and using the same laser beam as in Example 1 and in the same manner as in Example 1. Further, correction of the temperature of the molten metal, correction of the vapor thickness, and the like were performed in the same manner as in Example 1.

Using the apparatus of this example, measurement was performed continuously (in units of 2 seconds) for 17 minutes from the start to the end of blowing. As a result, a result almost coincident with FIG. 10 was obtained, and almost coincided with the chemical analysis value of the metal sampled at the sublance. Since the measurement in this example was a short time, the laser output wavelength was stable and did not change.

[0083]

As described above, according to the first aspect, a high-pressure gas is supplied to the surface of the molten metal in the probe immersed in the molten metal, and the gas is discharged in the vicinity of the molten metal. As a result, a stable molten metal surface can be easily obtained even in a molten metal under strong stirring or a molten metal having a large disturbance on the surface, and light irradiation is performed using the molten metal surface as a measurement surface. By applying the non-contact measuring means, it is possible to realize a high-accuracy and quick measurement of the components of the molten metal.

According to the second aspect of the present invention, a high-pressure gas is continuously supplied to the surface of the molten metal via the probe disposed above the surface of the molten metal, so that the molten metal or the surface under strong stirring is greatly disturbed. A stable molten metal surface can be easily obtained even in a molten metal in which a molten metal exists, and by using the molten metal surface as a measurement surface and applying non-contact measurement means by light irradiation, the molten metal can be obtained. Can be measured with high accuracy and speed, and continuously.

According to the third aspect of the present invention, a nozzle is provided on the side wall or bottom wall of the container holding the molten metal so as to be continuous with the molten metal in the container. By continuously supplying a high-pressure gas, a stable measurement surface can be easily obtained regardless of the molten metal under strong stirring or the molten metal in which a large disturbance is present on the surface, By applying non-contact measurement means by light irradiation using the measurement surface, it becomes possible to measure the component of the molten metal with high accuracy, quickly and continuously.

[Brief description of the drawings]

FIG. 1 is a diagram schematically showing a molten metal component measuring device according to a first embodiment of the present invention.

FIG. 2 is a schematic diagram showing a state where the apparatus of FIG. 1 is applied to a sublance of a converter.

FIG. 3 is a diagram schematically showing a molten metal component measuring device according to a second embodiment of the present invention.

FIG. 4 is a diagram schematically showing a molten metal component measuring device according to a third embodiment of the present invention.

FIG. 5 is a schematic diagram showing a state in which the apparatus of FIG. 4 is applied to a sublance of a converter.

FIG. 6 is a diagram schematically showing a molten metal component measuring device according to a fourth embodiment of the present invention.

FIG. 7 is a schematic diagram showing a state in which the apparatus of FIG. 6 is applied to a gas supply pipe for bottom blowing of a converter.

FIG. 8 is a graph showing a comparison between Mn measurement values and chemical analysis values in Example 1.

FIG. 9 is a graph showing the relationship between molten steel temperature and radiation light intensity.

FIG. 10 is a graph showing the results of continuously measuring Mn according to Example 2.

[Explanation of symbols]

 Reference Signs List 10 Probe 11 Sampling hole 12 Gas exhaust hole 13 Sampling chamber 14 Probe holder 15 Sublance 16 Temperature sensor 17 Vapor layer 18, 19 Bottom opening 20 Measuring surface forming means 21 Gas introducing mechanism 30 Measuring means 31 Light emitting unit 32 Measuring unit 33 Tip optical system 34, 35 Optical fibers 41a, 41b, 41c Laser light sources 53a, 53b, 53c: photodetector 54: computer L: molten metal (molten steel) S: measuring surface

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G01N 21/27 G01N 21/27 BD (72) Inventor Atsushi Chino 1-2-1, Marunouchi, Chiyoda-ku, Tokyo No. Nippon Kokan Co., Ltd. (72) Ikuhiro Sumi, Inventor 1-1-2 Marunouchi, Chiyoda-ku, Tokyo Japan Nippon Kokan Co., Ltd. (72) Yoshiki Kikuchi 1-2-1, Marunouchi, Chiyoda-ku, Tokyo Sun (72) Inventor Ryo Kawabata 1-2-1 Marunouchi, Chiyoda-ku, Tokyo F-term (reference) 2G052 AA12 AB01 AC24 AD06 AD46 BA13 CA02 CA04 DA01 DA22 GA11 2G055 AA22 BA01 CA09 DA04 DA31 EA10 FA02 2G059 AA01 BB04 CC03 DD12 EE02 EE11 FF07 FF08 GG01 GG03 HH02 HH06 JJ02 JJ17 JJ24 KK01 KK02 KK03 MM05 MM12 MM14 4K070 AB20 BE06 BE14 CG01

Claims (13)

[Claims] 1. A probe immersed in a molten metal and holding the molten metal therein, and a probe which continuously supplies a gas having a pressure higher than an atmospheric pressure from above to a surface of the molten metal in the probe. A measurement surface forming means for discharging the sample to the outside and forming a measurement surface on the surface of the molten metal in the probe; and irradiating the measurement surface with light containing a wavelength for component measurement through the probe, and determining a predetermined component based on the reflected light. And measuring means for measuring the concentration of the molten metal. 2. The probe has a cylindrical shape with a bottom and has a sampling hole provided on a side surface thereof for sampling a molten metal, and a gas discharge formed on the sampling hole and constituting the measurement surface forming means. Having a hole, and in a state where the probe is immersed in the molten metal to a position equal to or more than the upper edge of the gas discharge hole, the gas is sampled from the sampling hole and is put on the surface of the molten metal held by the probe. 2. The molten metal component measuring apparatus according to claim 1, wherein the measurement surface is formed by continuously supplying the gas and discharging the gas from the gas discharge hole. 3. The molten metal component measuring device according to claim 2, wherein the sampling hole and the gas discharge hole are formed integrally. 4. The apparatus according to claim 1, further comprising temperature measuring means for measuring the temperature of the molten metal.
The molten metal component measuring device according to any one of the above items. 5. The apparatus according to claim 1, further comprising: a radiation measuring unit configured to measure radiation emitted from the measurement surface when measuring a predetermined component of the molten metal by the measurement unit using the measurement surface. The melting according to claim 4, wherein the quality of the formation of the measurement surface of the molten metal is determined from the relationship between the radiation light intensity measured by the measuring means and the temperature of the molten metal measured by the temperature measuring means. Metal component measurement device. 6. The molten metal component measuring device according to claim 1, wherein the probe has a cylindrical shape with an open bottom for introducing molten metal. 7. A gas discharge hole provided on a side surface of the probe and constituting the measurement surface forming means, wherein the probe is immersed in molten metal to a position equal to or higher than an upper edge of the gas discharge hole. The component of the molten metal according to claim 6, wherein the measurement surface is formed by supplying the gas to the surface of the molten metal held in the probe and discharging the gas from the gas discharge hole. measuring device. 8. The molten metal component measuring apparatus according to claim 6, wherein the measurement surface is formed by supplying the gas into the probe and discharging the gas from an opening in the bottom. 9. A probe having a bottomless cylindrical shape and disposed above the surface of the molten metal, and continuously supplying a gas having a pressure higher than the atmospheric pressure from above toward the surface of the molten metal via the probe. A measuring surface forming means for forming a measuring surface on the surface of the molten metal; and a measuring means for irradiating the measuring surface with light including a wavelength for component measurement through the probe and measuring the concentration of a predetermined component based on the reflected light. A component measuring apparatus for molten metal, comprising: 10. A nozzle provided on a side wall or a bottom wall of a container for holding a molten metal so that a nozzle hole is connected to the molten metal in the container. Measuring surface forming means for continuously supplying gas at a high pressure and forming a measuring surface on the gas supply portion of the molten metal; and irradiating the measuring surface with light containing a wavelength for component measurement through the probe, and reflecting the light. Measuring means for measuring the concentration of a predetermined component based on light. 11. The measuring means for emitting a light including a component measuring wavelength, detecting a light amount of light reflected on the measurement surface, and obtaining a concentration of the predetermined component based on the detection result. A measuring unit, provided in or near the probe, a tip optical system for receiving light reflected from the measuring surface by irradiating light from the light emitting unit to the measuring surface,
11. The optical fiber according to claim 1, further comprising an optical fiber that guides light between the light emitting unit and the tip optical system and between the tip optical system and the measurement unit. 12. Metal component measurement device. 12. The light source is a laser beam, and the light-emitting unit includes a laser light source for one or more measurement components, a laser light source for a main component of a molten metal, and a laser for a reference light having no light absorption. The molten metal component measuring apparatus according to claim 11, further comprising: a light source; and an optical system that guides laser light from these light sources to the same optical path and also to an optical fiber. 13. The apparatus for measuring a component of a molten metal according to claim 6, further comprising a temperature measuring means for measuring a temperature of the molten metal.