JPH0441942B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a spectrum analyzer for optically identifying and quantifying substances in a blast furnace or other furnace using a probe consisting of a condensing lens or an optical fiber. It is something. [Prior Art] Conventionally, this type of device has been disclosed, for example, in Japanese Patent Application Laid-open No. 1983-
The one described in Publication No. 81540 is known. According to this, an optical fiber with a condensing lens facing the inside of the furnace (discharge atmosphere for molten metal) placed at one end and a spectroscope placed at the other end is inserted with a first gap. a first holding tube (concentrating cylinder); a first gas introducing means for flowing an inert gas into the predetermined gap from the other end side to the one end side of the first holding tube; a gas passage portion (discharge port) formed on the outer periphery of the optical lens for communicating between the inside of the furnace and the inside of the first holding tube;
and concentrically to the outer peripheral portion of the first holding tube, and
a second holding tube (protection tube) provided with a second predetermined gap; and a second gas introducing means for flowing an inert gas into the second predetermined gap from the other end side toward the one end side. and a cooling means for cooling the outer circumferential portion of the second holding tube, and further includes an adjuster that can finely move the first holding tube in the pipe length direction. [Problems to be Solved by the Invention] However, in the configuration of the prior art described above, since the measurement target is spectroscopic analysis of the discharge spectrum of molten metal, it is difficult to identify and quantify substances in the furnace such as gas generated in a blast furnace. unsuitable for doing so. In other words, since the tips of the first holding tube and the second holding tube are simply opened, it is difficult to stabilize the gas generated in the furnace that should be brought into the vicinity of the condensing lens, resulting in poor accuracy. It is not possible to perform good identification and quantification. More specifically, we aim to identify substances generated at high temperatures, in other words, gases that have a spectrum in the infrared region.
It is not possible to perform measurements that require high sensitivity, such as detecting the natural vibrations of gases. For example, Japanese Utility Model Application Publication No. 58-136755 discloses a device that detects infrared rays radiated from a portion to be measured of high-temperature exhaust gas, but such a configuration does not use lenses or optical fibers. Therefore, it has poor transmission properties and is prone to optical axis fluctuations, making it unsuitable for highly accurate and remote measurement of substances in the reactor. Additionally, Japanese Patent Application Laid-Open No. 59-81540 discloses a system that uses lenses and optical fibers to measure substances in the furnace, but this configuration allows direct visual observation of the particle size of molten ore. Even though this method does not perform spectral analysis, it does not have a means to stabilize the gas generated in the furnace and is not suitable for high-precision measurement of its components. An object of the present invention is to provide an apparatus that can easily and accurately identify and quantify substances in a blast furnace or the like using optical means. [Means for Solving the Invention] In order to achieve the above-mentioned object, the invention according to the present application provides a method in which a condensing lens facing the inside of the furnace is disposed at one end, and a spectrometer is disposed at the other end. In an apparatus provided with an optical fiber, a first holding tube into which the optical fiber is inserted with a first gap therebetween; a first gas introducing means, a first gas passage formed on the outer periphery of the condenser lens and communicating the vicinity of the condenser lens with the first gap, and a first gas passage portion concentrically formed on the outer periphery of the first holding tube. and a second holding pipe provided with a second gap therebetween; a second gas introducing means for flowing an inert gas into the second gap from the other end side toward the one end side; The probe includes a second gas passage portion that communicates between the inside of the furnace and the second gap, and a cooling means for cooling the outer peripheral portion of the second holding tube, and the probe further includes a second gas passage portion that communicates with the inside of the furnace. a distal end portion disposed in the distal end portion, a relay portion connected to the rear portion of the distal end portion and to which the second holding tube is connected to the rear portion, and movable in the longitudinal direction of the second holding tube; a lens mount part that can communicate with or shut off the second gas passage part by the movement, and a front opening in the tip part that communicates with the inside of the furnace and whose diameter decreases from the front to the rear; and a rear opening that communicates with the front opening and whose diameter increases from the front to the rear, a gas reservoir that communicates with the rear opening is formed in the relay part, and the lens mount part A first hollow part, a second hollow part, and a third hollow part communicating with the gas reservoir are formed in this order along the pipe length direction, and the first hollow part has the condenser lens. A lens holding member capable of holding the lens so that its optical axis is along the pipe length direction and in which the first gas passage section is formed is disposed, and the second hollow part has a length along the pipe length direction. The first holding tube is formed to have a focal length substantially equal to the focal length of the condenser lens, and the first holding tube is arranged in the third hollow portion such that the distal end surface of the optical fiber substantially coincides with the rear end position of the second hollow portion. Characterized by retained substances generated in the furnace,
In particular, a part of the generated gas is temporarily retained, and the light beam from the retained gas is made incident on a spectrometer so that the spectrum can be analyzed. Here, the furnace to which the present invention is applied is, for example, a blast furnace, a converter furnace, an electric furnace, a combustion furnace, a gas generating furnace, a boiler, a gas generating furnace, etc., and any furnace that can provide a light source inside the furnace may be used. . Note that a gas generating furnace is a furnace in which various gases exist, for example, a furnace in which gases are generated by various chemical reactions inside. In addition, the substances in the furnace may be gases, liquids, or solids, but if the furnace is a blast furnace, it is useful for accurately understanding the situation inside the furnace, such as identifying and quantifying SiO gas, etc. . Further, as the spectrometer, for example, a diffraction grating spectrometer, a Fourier transform spectrometer, a dispersive double beam spectrometer, etc. may be used. [Operation] When the material generated in the furnace is a gas body, a part of the gas body is retained in the gas reservoir section of the relay section. here,
The gas reservoir is formed at the rear of the opening whose diameter gradually decreases and then expands from the front to the rear, so if the lens mount is moved to stop the gas inflow from the second gas introduction means, the gas reservoir can be temporarily closed. The gas can be retained in the tank. It should be noted that since the inert gas from the second gas introduction means can expel the gas remaining in the gas reservoir, a standard spectrum similar to the so-called background can be measured at the time of this expulsion. [Embodiment of the Invention] FIG. 1 shows a probe 120 according to a first embodiment of the invention. This probe 120 is
The probe body 120A is roughly composed of a probe body 120A and a probe base 120B.
A tip member 101 (tip part), followed by a spacer 102 (relay part), a lens mount part 103, and a tube 107 arranged concentrically.
(second holding tube), tube 106, tube 105, etc. As shown in detail in FIG. 2, a spacer 102 is fitted into the tip member 101 and connected by welding, while moving from the front (left side in the figure) to the rear (right side in the figure). A front opening 101a whose diameter is gradually reduced toward an intermediate position is formed,
Further, a rear opening 101b whose diameter is gradually enlarged toward the rear is formed at the rear of the opening 101a so as to follow the opening 101a. The spacer 102 has the rear opening 101
A gas reservoir section 130 is formed which communicates with the gas reservoir section b, and a rear end section 130a of the gas reservoir section 130 has a diameter that is gradually reduced toward the rear. Moreover, the spacer 102
has two steps 102a, 102 on the rear outside thereof.
b is formed, and a fitting hole 102c communicating with the gas reservoir portion 130 is further formed. The pipe 105 is fitted into the stepped part 102a of the spacer 102, the pipe 106 is fitted into the other stepped part 102b, and the pipe 106 is fitted into the fitting hole 102c.
07 is fitted. A first passage 1 is provided between the pipe 105 and the pipe 106.
28 is formed, and a second passage 127 is formed between the tube 106 and the tube 107. and,
A water passage opening 129 is formed in the pipe 106 so that the second passage 127 and the first passage 128 communicate with each other. Note that the first passage 128 and the second passage 1
27 communicate with a cooling water outlet 110 and a cooling water inlet 111, respectively, which constitute the cooling means (see FIG. 1). In addition, the tube 107 and the tube 1 serving as the first holding tube
08 (see FIG. 1) is a gap 163 (second gap) between the gas inlet 112 and the second gas introduction means provided in the probe base 120B.
is connected to. Next, the lens mount section 103 will be explained with reference to FIGS. 3 to 7. The lens mount section 103 is a lens mount body 103.
A, lens holding member 142, spacer ring 14
4, a holding member 146, and a condensing lens 12.
4 is housed within the lens holding member 142.
A hollow portion along the longitudinal direction is formed in the lens mount main body 103A, and the hollow portion is divided into a first hollow portion 148, a second hollow portion 150, and a third hollow portion 125, which are formed in order to have smaller diameters. has been done. Note that while the lens holding member 142 is attached to the first hollow part 148, a groove 152 having an inner diameter slightly larger than the inner diameter of both the front and rear sides is formed at an intermediate position of the first hollow part. There is. The length of the second hollow portion 150 in the longitudinal direction, that is, in the optical axis direction is approximately equal to the focal length of the condenser lens 124 . Furthermore, as can be understood from FIGS. 4 and 5, a groove 154 (second gas passage section) extending along the longitudinal direction (the optical axis direction) is provided on the outer peripheral portion of the lens mount body 103A. The number of grooves 154 may be arbitrary, but in this embodiment, four grooves are provided. A screw hole 157 communicating with the third hollow portion 125 is provided in the lens mount body 103A. The lens holding member 142 has a front hollow part 142a and a rear hollow part 142b divided into two stages, and the inner diameter of the front hollow part 142a is approximately the same as the outer diameter of the lens 124. Also,
The boundary between both hollow parts 142a and 142b is formed in a shape that follows the curved surface of the lens 124. On the outer peripheral part of the lens holding member 142, a third
As shown in the figure, a groove 156 (first
A groove 158 extending in the radial direction and communicating with the groove 156 is formed on the rear (right side in the drawing) side surface. Note that when the lens holding member 142 and the pressing member 146 are assembled to the lens mount main body 103A, the groove 156 of the lens holding member 142 and the pressing member 146
It communicates with a groove 160 formed on the rear surface side. Similar to the case of the groove 154, the groove 160 and the groove 15
The number of grooves 6 and 158 may be arbitrary, but in this embodiment, four of each are provided. The condensing lens 124 is connected to the spacer ring 1
44 into the lens holding member 142, and the lens holding member 142 is housed in the lens mount main body 103A as described above.
The condenser lens 124 is held and pressed by the pressing member 146. In the drawing, presser member 1
46 and the lens mount main body 103A are not shown, but screws or the like may be used at appropriate positions. Note that as the condenser lens 124, for example, a ZnSe lens is used. FIG. 8 shows details of the vicinity of the tip of the probe 120 with the lens mount section 103 assembled.
03 is fitted into the tube 107 so as to be movable in the longitudinal direction of the tube. As shown in the figure, a tube 108 (first holding tube) is fitted into the third hollow part 125 of the lens mount main body 103A, and is connected by a screw (not shown) that is screwed into a screw hole 157. tube 1
08 is fixed to the lens mount main body 103A. There is a gap 162 (first gap) in the pipe 108.
The optical fiber 109 is inserted through the gap 162, and the gap 162 communicates with an external gas inlet (not shown) serving as a first gas introduction means. Note that from the tip of the probe 120 to the lens 124
The distance to this point corresponds to L in the formula I=I ₀ exp (-kLλ) which gives the intensity I of the spectrum. Next, an example of how the probe 120 according to this embodiment is used will be described with reference to FIG. 9 and the like. First, the 8th
After inserting the probe 120 in the assembled state shown in the figure into the position to be measured in the furnace, inert gas, such as nitrogen gas, is introduced into the gap 162 from the external gas inlet, which is the first gas introducing means (not shown). flows into. The inert gas that has flowed into the gap 162, the second hollow part 150, the groove 158, and the groove 15.
6, it is ejected to the front surface of the lens 124 through the grooves 152 and 160. Since this gas flow of inert gas continues to flow out to the front surface of the lens 124, the lens surface of the lens 124 is always kept clean and is prevented from being damaged by dust etc. blown from inside the furnace. Subsequently, when the lens mount section 103 is moved rearward by an appropriate means, as shown in FIG.
Front surface of lens mount section 103 and spacer 102
A gap 170 is formed between the two. In this state, when inert gas is introduced from the gas inlet 112, which is the second gas introduction means, the inert gas flows through the pipe 1.
07, the gas reservoir 130 and the front opening 10 through the groove 154 and the gap 170.
Flows into 1a. Therefore, the gas reservoir 130 is in a state purged with an inert gas, and by measuring the spectrum inside the gas reservoir 130 in this state, a standard spectrum for the so-called background can be obtained. Next, when the gas inflow from the gas inlet 112 is stopped, the furnace gas flows from the front opening 101a to the rear opening 101b, the gas reservoir 130, and the gap 1.
70, groove 154, and flows toward gas inlet 112. In this case, the tip member 101 has a front opening 10.
1a and the rear opening 101b are formed, the furnace gas flowing from the front opening 101a reaches the gas reservoir 130. When the gas reservoir section 130 is filled with furnace gas, the lens mount section 103 is moved forward. As a result, the gap 170 is shut off, so that the furnace gas remains in the gas reservoir 130 in a stable state. By measuring the spectrum at that time, the in-furnace gas can be identified and quantified with high accuracy. In this embodiment, the furnace gas is discharged from the gas inlet 112 after the gas inflow from the gas inlet 112 is stopped, but a gas exhaust port is provided separately from the gas inlet 112. In addition, the furnace gas may be discharged through the discharge port. During the measurement, if cooling water is supplied from the cooling water inlet 111, the cooling water flows to the cooling water outlet 110 via the second passage 127, the water passage opening 129, and the first passage 128, so that the probe 120 can be protected from the high heat in the furnace. Furthermore, in this embodiment, the condenser lens 124 is housed in the first hollow part 148 of the lens mount section 103, and the optical fiber 109 is disposed behind the condenser lens 124. Compared to a configuration in which the internal rays are directly focused, a spectrum with an intensity approximately 8 times higher can be obtained.
Identification and quantification of substances in the reactor can be performed more accurately and quickly. Next, the overall configuration of a measuring device using the probe 120 and an example of its experimental data will be explained. As shown in FIG. 10, this measuring device includes an electric furnace 501
A probe 120, a diffraction grating spectrometer 502, an infrared detector 503, and a preamplifier 504 inserted into the
A, autolock-in amplifier 504B with oscilloscope 504C, calculator 505, recorder 50
It is roughly composed of 6. In this experimental example, a spectrometer 502 having specifications shown in Table 1 below was used.

【table】

[Table] The light beam separated into a single wavelength by the spectrometer 502 is emitted to the outside from a slit 502a on the exit side. The emitted light is collected by the ZnSe lens 507 and focused on the window of the infrared detector 503. As shown in FIG. 11, this ZnSe lens 507 transmits about 70% of infrared light in the infrared region (see curve R1), but if anti-reflection coating is applied, the transmittance at 8.0 μm, for example. can be increased to approximately 99% (see curve R2). Table 2 below shows the specifications of the ZnSe lens 507. The lens 507 may be appropriately selected from lenses with different transmission wavelengths depending on the object to be measured.

[Table] In this example, an infrared detector 503 was used as the photoelectric conversion device, and the specifications of the infrared detector are shown in Table 3 below. Needless to say, the infrared detector 503 converts the intensity of infrared light into an electrical signal, and the light that has passed through the ZnSe lens 507 passes through a window material made of germanium, and is further attached to the rear of the window material. The light is focused on a photoelectric conversion element (made from an alloy of mercury, cadmium, tellurium, etc.). FIG. 12 shows the wavelength sensitivity characteristics of the infrared detector 503.

[Table] The electrical signal obtained from the infrared detector 503 is amplified approximately 20 times by a preamplifier 504A, and then sent to an autolock-in amplifier 504B. Table 4 shows the auto lock-in amplifier 504.
This shows the specifications of B. An oscilloscope 504C attached to the autolock-in amplifier 504B monitors the phase shift based on the waveform of the electrical signal.

[Table] The arithmetic unit 505 is an autolock-in amplifier 5
It is calculated based on the output signal from 04B. For example, if the output voltage of the autolock-in amplifier 504B at standard time, that is, when no spectral absorption occurs, is A, and the output voltage at the time of measurement is B, then
Since these signals are analog signals, both analog signals were converted to digital signals to facilitate calculation processing, and then the B/A calculation was performed, and the calculation result was converted back to an analog signal. It is then sent to recorder 506. The recorder 506 continuously and simultaneously records the output voltage B of the autolock-in amplifier 504B and the output signal (corresponding to transmittance B/A) of the arithmetic unit 505. FIG. 16 shows an example of measurement when spectrum absorption occurs, and FIG. 17 shows an example of measurement when absorption does not occur. In FIGS. 16 and 17, the upper curve corresponds to the output of the arithmetic unit 505, and the lower curve corresponds to the output of the autolock-in amplifier 504B. The output of autolock-in amplifier 504B is
The output voltage A is recorded as being proportional to the intensity of the absorption peak, but if no absorption occurs, the output voltage A
Since there is no output difference between
When A=1, the output of the arithmetic unit 505 remains constant; however, when absorption occurs, the output difference becomes large and B/A<1, and the output of the arithmetic unit 505 becomes constant.
The output appears smaller on the chart than in the case without absorption. Note that the blacked out portions in the output curve of the autolock-in amplifier in FIG. 16 are portions that are not recorded due to the occurrence of absorption. Next, a method for identifying and quantifying substances in the reactor will be explained. In this example, identification and quantification were performed in a laboratory instead of in an operating furnace. That is, as shown in FIG. 10, a reaction tube 301 was placed inside an electric furnace 501, and measurements were carried out in a state where an operating furnace was reproduced inside the reaction tube 301. In this example, measurements were performed on the samples described below. Sample 307 used in this example is (Al-Si) + slag alloy (SiO ₂ -CaO
-Al ₂ O ₃ ), SiO ₂ +C, SiO ₂ +Si, and solid SiO
It is. The preparation of each sample will be described below. Al-Si alloys were created in which the Si (wt%) was changed stepwise to 95, 90, and 80%. Further, the weight ratio was calculated in advance, and Al and Si were placed in a crucible and melted at 1500°C for 1 hour. The obtained sample was ground in a mortar and used. Slag (SiO ₂ −CaO−Al ₂ O ₃ ) is SiO ₂ :
The weight ratio of CaO:Al ₂ O ₃ =5:3:1 was 50 g in total. Mix each weighed sample and place it in a crucible at 1500 ml.
℃ for 1 hour. The obtained slag was ground in a mortar and used. In the measurement, a mixture of Al-Si alloy and slag was used. The weight ratio is Al-Si alloy: slag = 1:2
So, the total was 7.5g. SiO ₂ in SiO ₂ +C was 99.99% pure (manufactured by Rare Metallic Co., Ltd.) and water was removed in a dryer (120°C).For the carbon, graphite (manufactured by Tokai Konetsu Co., Ltd.) was ground to about 100 μm using a vibration mill. After that,
It was fired in an Ar gas atmosphere at 1200℃. The measurement is based on the weight ratio of SiO ₂ and carbon: SiO ₂ :C=1:2
A total of 6 g was mixed in a mortar and used. The Si in SiO+Si used was one with a purity of 99.9% (manufactured by Rare Metallic Co., Ltd.) and water was removed in a dryer (120°C). The measurement was carried out using the weight ratio of Si and SiO ₂ as Si:SiO ₂ =
The ratio of 1:1 was 3 g in total, which was mixed in a mortar and used. SiO has a purity of 99.95% or more (manufactured by Osaka Titanium Co., Ltd.)
The water was removed in a dryer (120°C atmosphere), and the mixture was ground in a mortar and used. As shown in FIG. 10, a carrier gas (Ar,
_H2 gas) was flowed (in to out), and a radiation plate 303 was provided near the sample 307. First, after inserting the probe 120 into the reaction tube 301, the radiation plate 303 and the probe 120
The sample 307 is placed between the tip of the radiation plate 3
A thermocouple 309 is provided so as to be in contact with 03. During the measurement, the sample 307 is placed in a boat made of recrystallized high-purity alumina (manufactured by Nihon Kagaku Togyo Co., Ltd.) and set at the center of the electric furnace 501. Next, the inside of the reaction tube 301 is evacuated and it is confirmed that there is no vacuum leakage. After that, Ar gas is poured in to create a vacuum again. This operation is repeated about three times to replace the inside of the reaction tube 301 with Ar gas. After that, the electric furnace 501 is heated by electricity, but when the temperature rises, the vacuum pump is bypassed so that the same amount of Ar gas flowing into the reaction tube 301 can be removed, and the pressure inside the reaction tube 301 is brought down to atmospheric pressure. Adjust with a needle valve so that they are equal. The spectrum measurement was performed in the range of 5000 to 800 cm ^-1 when the inside of the reaction tube 301 reached a predetermined temperature. Table 5 below shows the experimental conditions at this time.

[Table] As a result of spectrum measurement of the materials in the furnace using the method described above, the sample was Al-Si alloy + slag,
Spectra of SiO gas could be confirmed in the case of solid SiO, SiO ₂ +C, and SiO ₂ +Si, but in the Ar gas atmosphere, the most remarkable spectrum was observed when the sample was SiO ₂ +C. FIG. 13 shows an example in which the SiO gas absorption spectrum appears best. In the figure, the vertical axis represents infrared intensity (%) and the horizontal axis represents wave number (cm ^-1 ). Measurements were carried out from 5000 to 800 cm ^-1 . 1st
The curve shown in the upper part of Figure 3 shows the case where carrier gas Ar is flowed at a flow rate of 5 c.c./min, the furnace temperature is 1500℃, and the sample is
This is when SiO ₂ +C is used. As shown in the figure, 2445.5 ~ 2386.6 cm ^-1 , 2293.6 ~ 2202.6 cm ^-
1 , peaks showing absorption in the ranges of 1251.1 to 1166.9 cm ^-1 and 1126.1 to 1044.9 cm ^-1 (2400, 2250,
1200, 1082) appeared. Each absorption peak corresponds to CO ₂ gas, CO gas, double vibration of SiO gas, and Si ₂ O ₂ gas, respectively. The curve shown at the bottom of Figure 13 represents the carrier gas.
This was measured by replacing Ar gas with H ₂ .
According to this, it can be seen that new sharp absorption spectra appear at each position of 3000, 1500, and 1000 cm ^-1 . These three new absorption peaks indicate absorption of OH groups. When the interior of the reaction tube 301, which had been slowly cooled in an Ar gas atmosphere after the completion of the above steps, was looked at, an amber vapor deposit was observed on the surface facing the spectrometer from the sample boat. In particular, more deposits were seen at a position about 200 mm from the radiation plate 303. According to materials from Osaka Titanium Co., Ltd., the general properties of SiO thin films are
It is stated that the SiO film exhibits an amber color when deposited under a low oxygen partial pressure of 1×10 ⁻⁵ torr or less. From this, the amber-colored vapor deposit in the reaction tube 301 is
It is easy to understand that it is SiO. The amber deposit was investigated using a Fourier transform infrared spectrometer. The measurement is
The KBr granular crystals and the deposit were crushed in a mortar, and the mixture was press-molded at a pressure of 200 Kg/cm ² , and this was set in the spectrometer 502. Figure 15 shows the measurement results, and according to this, 1289,
Absorption appeared at 1216, 1180, 1172, and 1165 cm ^-1 . Incidentally, in order to verify the above measurement results, the same measurements were performed on the KBr window material of the infrared detector 503. FIG. 14 shows the measurement results. Table 6 shows the absorption wavenumbers of SiO published by other studies. Comparing the same table and the above results, we can see that the absorption at nearly the same wave number is 1216 cm ^-1 ( ²⁹ Si ¹⁶ O),
1180cm ^-1 ( ²⁸ Si ¹⁸ O), 1172 cm ^-1 ( ²⁹ Si ¹⁸ O), 1165
cm ⁻¹ ( ³⁰ Si ¹⁸ O). This absorption corresponds to the absorption wavenumber of the SiO solid. It can also be understood from this result that the absorption wavenumber changes as the mass number changes. From the above results, it was confirmed that SiO gas was generated within the reaction tube.

[Table] FIG. 18 shows a probe 120 according to a second embodiment. In this embodiment, a cap 401 is provided at the tip of the tip member 101 in the first embodiment. This cap 40
1 has a hole 401 communicating with the front opening 101a.
A is formed, and a small hole 403 is further formed to communicate the hole portion 401a with the inside of the furnace. Other configurations and operations are the same as those in the first embodiment, so redundant explanations will be omitted. Preferably, the length of the hole 401a along the longitudinal direction of the probe is about 10 times the inner diameter thereof.
Note that this length corresponds to the same length as L in the formula for giving the spectrum intensity described in the first embodiment. The cap 401 may be made of any material as long as it can serve as a light radiator, and is made of carbon or the like, for example. This example is a probe for measuring gas, and the gas inside the furnace is passed through the small hole 403 to the hole 401a.
will be introduced in On the other hand, since it also functions as a radiator, reflected light from inside enters the condenser lens 124. In the second embodiment, since the gas to be measured is isolated from the atmosphere inside the furnace, even if the situation inside the furnace changes drastically, the measurement can be carried out in an extremely stable state without being affected by the change. [Effects of the Invention] As described above in detail, according to the present invention, the condenser lens facing the inside of the furnace is disposed on one end side,
In a spectrum analyzer including an optical fiber having a spectrometer disposed at the other end thereof, a first holding tube into which the optical fiber is inserted with a first gap therebetween, and one end inserted from the other end side into the first gap. a first gas introducing means for flowing an inert gas toward the side; a first gas passage portion formed on an outer peripheral portion of the condensing lens and communicating the vicinity of the condensing lens with the first gap; ,
a second holding tube concentrically with the outer circumferential portion of the first holding tube;
a second holding pipe provided with a gap therebetween; a second gas introducing means for flowing an inert gas into the second gap from the other end side toward the one end side; The probe includes a second gas passage portion communicating with the gap, and a cooling means for cooling the outer peripheral portion of the second holding tube, and the probe further includes a tip portion disposed inside the furnace. and the second part is connected to the rear part of the tip part, and the second part is connected to the rear part of the tip part.
It consists of a relay part to which the holding tube is connected, and a lens mount part that is movable in the longitudinal direction within the second holding tube and can communicate or block the second gas passage part by the movement, The portion includes a front opening that communicates with the inside of the furnace and whose diameter decreases from the front to the rear, and a rear opening that communicates with the front opening and whose diameter increases from the front to the rear. a gas reservoir portion communicating with the rear opening portion is formed in the relay portion, and a first hollow portion, a second hollow portion, and a third hollow portion communicating with the gas reservoir portion are formed in the lens mount portion. portions are formed in that order along the pipe length direction, the first hollow portion is capable of holding the condenser lens with its optical axis along the pipe length direction, and the first gas passage portion is A holding member is disposed in which a holding member is formed, the second hollow portion has a length along the pipe length direction that is approximately the focal length of the condensing lens, and the third hollow portion has a holding member formed with a distal end of the optical fiber. The first holding tube is held so that its surface substantially coincides with the rear end position of the second hollow part, so that it can be temporarily and stably placed in the gas reservoir by a simple movement of the lens mount part. It is possible to accurately and easily identify and quantify the gases generated in the furnace, where the behavior of the dipole moment among the molecular vibrations is a problem. Therefore, furnaces widely used in various industries can be properly operated.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of the probe according to the first embodiment, FIG. 2 is an enlarged sectional view of the vicinity of the tip member of the probe shown in FIG. 1, and FIG. 3 is an exploded sectional view showing the lens mount part thereof. Figure 4 is a sectional view taken along the - line in Figure 3, Figure 5 is an end view seen from the direction of Figure 3, Figure 6 is an end view seen from the direction of Figure 3, and Figure 7 is a cross-sectional view taken from the direction of Figure 3. 3 is an end view seen from the direction shown in FIG. 8, and FIG. 8 is a sectional view showing the state in which the lens mount part is inserted into the tip of the probe until it contacts the relay part.
Fig. 9 is a cross-sectional view showing the state in which the lens mount is retracted, Fig. 10 is a block diagram showing the overall configuration of the spectrum analyzer, Fig. 11 is a graph showing the transmission characteristics of the condensing lens, and Fig. 12 is A graph showing the wavelength sensitivity characteristics of an infrared detector; FIG. 13 is a graph showing the relationship between the intensity of infrared rays and the wave number of the material inside the reactor;
Figure 14 is a graph showing the infrared spectrum of the window material of the infrared detector, Figure 15 is a graph showing the infrared spectrum of the vapor deposited material, and Figure 16 is the relationship between wave number, output voltage, and transmittance when absorption occurs. FIG. 17 is a graph showing the relationship between wave number, output voltage, and transmittance when there is no absorption, and FIG. 18 is a cross-sectional view of the probe according to the second embodiment. Explanation of symbols, 101...Tip member, 101a...
...Front opening, 101b...Rear opening, 102
... Spacer (relay part), 103 ... Lens mount part, 109 ... Optical fiber, 120 ... Probe, 112 ... Gas inlet (second gas introduction means), 124 ... Condensing lens, 125 ... Third hollow part, 108... pipe (first holding pipe), 107...
Pipe (second holding tube), 111... Cooling water inlet (cooling means), 142... Lens holding member, 148...
First hollow part, 150... Second hollow part, 154...
Groove (second gas passage part), 156... Groove (first gas passage part), 162... Clearance (first gap), 163
...Gap (second gap).

Claims (1)

[Scope of Claims] 1. A spectrum analyzer equipped with an optical fiber having a condensing lens facing the inside of the furnace at one end and a spectrometer at the other end, wherein the optical fiber is located at its outer periphery. a first holding tube to be inserted with a first gap therebetween; a first gas introducing means for flowing an inert gas into the first gap from the other end side toward the one end side; a first gas passage formed on the outer periphery of the lens and communicating the vicinity of the condensing lens with the first gap; and a second gas passage formed concentrically on the outer periphery of the first holding tube, with a second gap provided therein. A second holding pipe provided, a second gas introducing means for flowing an inert gas into the second gap from the other end toward the one end, and communication between the inside of the furnace and the second gap. a second gas passage section for cooling the second holding tube, and a cooling means for cooling the outer peripheral section of the second holding tube.
The probe further comprises: a tip disposed inside the furnace; a relay section connected to a rear part of the tip and connected to the second holding tube; a lens mount part that is movable in the lengthwise direction of the second holding pipe and that can communicate with or block off the second gas passage part by said movement; the tip part communicates with the inside of the furnace; and,
A front opening whose diameter decreases from the front to the rear, and a rear opening that communicates with the front opening and whose diameter increases from the front to the rear, and the relay part has a diameter that decreases from the front to the rear. A communicating gas reservoir is formed, and the lens mount includes a first hollow section, a second hollow section, and a third hollow section communicating with the gas reservoir.
Hollow parts are formed in this order along the pipe length direction, and the first hollow part is capable of holding the condenser lens with its optical axis along the pipe length direction, and the first gas passage is A lens holding member having a section formed therein is disposed, the second hollow section is formed to have a length along the tube length direction that is approximately the same as the focal length of the condensing lens, and the third hollow section is provided with a lens holding member that holds the light. A spectral analysis device for a substance in a furnace, characterized in that the first holding tube is held such that a tip end surface of the fiber substantially coincides with a rear end position of the second hollow part.