JP2010190754A - Device and method for diagnosing deterioration of sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily diagnose deterioration of optical fibers without relying on the degree of skill, and perform economical cost reduction in terms of maintenance in a furnace-inside monitoring device. <P>SOLUTION: The deterioration diagnosis system includes: a cylindrical body (23) to which the rear end side of a sensor unit (12) drawn out from a combustion furnace (40) is attached; a light source (21) for diagnosis for making diagnostic light (22) incident on the tip surfaces of optical fibers (11) exposed to the tip of the sensor unit (12) attached to the cylindrical body (23); and an image diagnostic device (30) for displaying a diagnostic image (34) for diagnosing the transmittance of the optical fibers (11), along with picking up an image of the diagnostic light (22) outgoing from the rear end surfaces of the optical fibers (11) exposed to the rear end surface of the sensor unit (12). <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a deterioration diagnosis apparatus for a sensor provided for monitoring combustion in a furnace in a combustion furnace and a method thereof.

  In a combustion furnace such as a boiler of a thermal power plant or an incinerator for waste treatment, it is necessary to monitor the ignition or extinguishing of a burner, the combustion state in the furnace, and the like. For this purpose, an in-furnace monitoring device using an optical fiber scope that detects a flame in the furnace is used. The in-furnace monitoring apparatus is provided with an optical sensor for acquiring a lot of image information. For example, 90 or more optical sensors are installed in the boiler of a 1 million kW thermal power plant.

  As a conventional in-furnace monitoring device 50, as shown in FIG. 6 (A), an optical fiber 51 is provided as an optical sensor for detecting light of a flame burning in the combustion furnace 60, for example, infrared ray 61. A sensor unit 52 is attached to the tip of the rod unit 53. The middle of the rod portion 53 is inserted into the combustion furnace 60.

For example, three optical fibers 51 having a diameter of about 1 mm are fixed in the body of the sensor unit 52 in the vertical direction. From the end face of each optical fiber 51, the flame infrared rays 61 are introduced.
Infrared rays 61 guided from the front end surfaces of the optical fibers 51 are propagated to the process operation device 55 through the transmission optical fiber 54 extended to the rear side of the rod portion 53. The process arithmetic unit 55 includes a PHD (photo detector), an amplifier, an arithmetic circuit, and the like.
Light (infrared ray 61) is changed to a current (resistance value) by PHD, amplified by an amplifier, and then input to an arithmetic circuit. Then, it is judged (diagnosis) whether there is a flame in the furnace, whether it is completely burned, or the like. As a result of the determination, if it is necessary to control the combustion state in the furnace, the amount of air flowing into the combustion furnace 60 is increased to strengthen the flame or stop the operation.

  Of the three optical fibers 51 arranged in the vertical direction, the uppermost optical fiber 51a faces the horizontal direction, and the lower optical fiber 51b is obliquely downward at an angle of about 15 °. The lowermost optical fiber 51c is inclined obliquely downward at an angle of about 30 ° from the horizontal direction. This is so that a single in-furnace monitoring device 50 can detect a wide range in the vertical direction in the furnace.

  As the conventional in-furnace monitoring apparatus 50, what is shown by patent document 1 corresponds. In addition, Patent Document 2, Patent Document 3, and the like can be cited.

JP-A 61-139726 Japanese Patent Laid-Open No. 5-288480 JP-A-11-142238

  Now, as shown in FIG. 6B, impurities are gradually deposited on the tip surface of the optical fiber 51 exposed to the inside of the combustion furnace 60 due to some chemical reaction. It is empirically known that the sensitivity of the sensor decreases with time due to this impurity deposition (this phenomenon is hereinafter referred to as “aging over time” of the optical fiber). If the deterioration over time occurs, the light transmittance in the optical fiber 51 is lowered. Therefore, it is necessary to periodically check the transmittance. This is because it is not possible to determine whether the amount of incident infrared light is small due to weak combustion or whether the amount of incident infrared light is small due to aging.

Accordingly, the determination as to whether or not aging has occurred is made by determining whether the maintenance staff of the in-furnace monitoring device 50 has pulled out the rod part 53 from the furnace wall of the boiler and the optical fiber of the sensor part 52 attached to the tip of the rod part 53 The tip surface of 51 is visually inspected. In this visual inspection, whether or not the optical fiber 51 is usable is determined by skilled judgment. Since the diameter of the optical fiber 51 employed in the in-furnace monitoring device 50 is as thin as about 1 mm, skill is required to make a judgment by looking at its tip surface.

  The current method for determining deterioration over time is largely due to the skill of maintenance personnel, and it is considered that there are variations in the determination of the deterioration status. Therefore, the accuracy of the deterioration determination may not necessarily be high. In other words, since the accuracy of the deterioration determination is not good, there is a possibility that it is actually used but discarded. In this case, since the optical fiber 51 used for the sensor unit 52 is expensive, a large loss occurs economically. On the other hand, if it is determined that the optical fiber 51 is sufficiently aged but can be used, and if it is used continuously, the safety device will work and cannot be operated even if the boiler is operated. Arise.

  The problem to be solved by the present invention is to provide a technique capable of diagnosing deterioration of a sensor used in a boiler without depending on skill level.

(First invention)
The first invention in the present application, the rod portion (13) attached to the combustion furnace (40) for extracting light (41) from the internal space of the combustion furnace (40) to the outside of the combustion furnace (40), A sensor part (12) attached to the rod part (13), and one piece for guiding the light (41) from inside the combustion furnace (40) held by the sensor part (12) and taking it out In an in-furnace monitoring device (10) comprising the above optical fiber (11) and a process operation device (15) for inputting light (41) guided by the optical fiber (11), the optical fiber The present invention relates to a sensor deterioration diagnostic apparatus (20) for diagnosing the transmittance of (11).
The sensor deterioration diagnosis device (20) includes a cylindrical body (23) to which the rear end side of the sensor section (12) extracted from the combustion furnace (40) is attached, and a sensor attached to the cylindrical body (23). A diagnostic light source (21) for injecting diagnostic light (22) into the tip surface of the optical fiber (11) exposed at the tip of the section (12), and an optical fiber exposed at the rear end surface of the sensor section (12) ( 11) An image diagnostic device (30) for imaging diagnostic light (22) emitted from the rear end face and displaying a diagnostic image (34) for diagnosing the transmittance of the optical fiber (11) .

(Function)
When the diagnostic light (22) of the diagnostic light source (21) is incident on the front end surface of the optical fiber (11), it propagates through the optical fiber (11) and exits from the rear end surface of the optical fiber (11). Since the cylindrical body (23) is completely dark, the diagnostic light (22) emitted from the rear end face of the optical fiber (11) is clear. The diagnostic light (22) is captured by the diagnostic imaging apparatus (30) and displayed on the diagnostic image (34).
The diagnostic image (34) is objective because it reflects the transmittance of the optical fiber (11) of the sensor unit (12), and it can be diagnosed easily and accurately even if it is not skilled in degradation diagnosis. it can.

(Variation 1 of the first invention)
The first invention can also provide the following variations.
That is, the diagnostic light (22) generated by the diagnostic light source (21) is flat illumination in which the illuminance of light is spatially constant.

(Function)
Since the diagnostic light source (21) is a flat illumination, especially when using a plurality of optical fibers (11), the variation in brightness incident on the plurality of optical fibers (11) is small, The transmittance can be diagnosed by comparing a plurality of optical fibers (11).

(Variation 2 of the first invention)
The first invention can also provide the following variations.
That is, the diagnostic imaging device (30) is a computing device (36) that digitizes the brightness of the diagnostic image (34), and a measured value of the brightness calculated by the computing device (36), a preset optical fiber ( This is a sensor deterioration diagnosis device (20) provided with a comparison / determination device (37) for judging the transmittance of the optical fiber (11) in comparison with the threshold value of the unusable luminance in 11).

(Function)
Instead of simply looking at the diagnostic image (34) and making a diagnosis, the brightness of the diagnostic image (34) can be converted into a numerical value and automatically diagnosed. In other words, when the measured value (calculated value) of the luminance is below the “threshold value”, it can be automatically diagnosed that the optical fiber (11) is not usable (replacement time).

(Variation 3 of the first invention)
The first invention can also provide the following variations.
That is, the diagnostic imaging apparatus (30) calculates how much the luminance of the diagnostic image (34) is different from the threshold value, and how much until the calculated value reaches the threshold value. This is a sensor deterioration diagnosis device (20) having a function of predicting whether there is a surplus of usage period and feeding back the predicted information to the process operation device (15) in normal operation.

(Function)
Since the “threshold value” can be determined objectively, it can be used until it almost reaches the “threshold value” without taking measures such as unnecessarily increasing the “threshold value”. In addition, since the deterioration information of the optical fiber (11) can be fed back to the in-furnace monitoring device (10) in normal operation, it can be used almost immediately before the use limit, so the replacement time of the optical fiber (11) can be set appropriately. can do. As a result, maintenance cost can be reduced.

(Second invention)
The second invention in the present application is the rod part (13) attached to the combustion furnace (40) for taking out light (41) from the internal space of the combustion furnace (40) to the outside of the combustion furnace (40), A sensor part (12) attached to the rod part (13), a cylindrical body (23) attached to the rear end side of the sensor part (12), and a combustion furnace held by the sensor part (12) (40) one or more optical fibers (11) for introducing light from the inside and taking it out to the outside, and a process operation device (15) for inputting the light guided by the optical fiber (11), In the in-furnace monitoring device (10), the rear end side of the sensor part (12) removed from the rod part (13) extracted from the combustion furnace (40) is connected to the cylindrical body (23 ) To the sensor deterioration diagnosis method for diagnosing the transmittance of the optical fiber (11).
That is, a diagnostic light incident procedure in which diagnostic light (22) is incident on the distal end surface of the optical fiber (11) exposed at the distal end of the sensor unit (12), and the incident diagnostic light (22) is the light Diagnostic light (22) propagating through the fiber (11) and exiting from the rear end face of the optical fiber (11) is received by the diagnostic imaging apparatus (30) attached to the rear end side of the cylindrical body (23). An imaging procedure for imaging, and an image diagnostic procedure for diagnosing the transmittance of the optical fiber (11) based on a diagnostic image (34) acquired by the imaging procedure.

(Variation 1 of the second invention)
The second invention can also provide the following variations.
That is, in the diagnostic light incident procedure, the diagnostic light (22) that makes the flat illumination whose light illuminance is spatially constant is incident.

(Variation 2 of the second invention)
The second invention can also provide the following variations.
That is, in the diagnostic imaging procedure, the brightness of the diagnostic image (34) obtained by imaging the diagnostic light (22) is compared with a preset threshold of brightness at which the optical fiber (11) cannot be used. It includes a procedure for determining the transmittance of the fiber (11).

(Variation 3 of the second invention)
The second invention can also provide the following variations.
That is, the diagnostic imaging procedure calculates how much the luminance of the diagnostic image (34) is different from the threshold value, and how long the usage period is until the calculated value reaches the threshold value. It includes a procedure for predicting whether there is room and feeding back the predicted information to the process operation device (15) in normal operation.

According to the first to fourth aspects of the invention, it is possible to provide a sensor deterioration diagnosis apparatus that can perform sensor deterioration diagnosis without depending on skill level.
According to the inventions described in claims 5 to 8, it is possible to provide a sensor deterioration diagnosis method capable of performing sensor deterioration diagnosis without depending on skill level.

It is a schematic explanatory drawing which shows the sensor deterioration diagnostic apparatus in the in-furnace monitoring apparatus of embodiment of this invention. (A) is a top view of the arrow II-II line | wire of FIG. 1, (B) is a perspective view of a sensor part. (A) is a detailed view of FIG. 1 cylindrical body and a lens, (B) is a top view of the arrow III-III line of (A). It is a schematic waveform diagram of diagnostic light. (A) is a plan view of a diagnostic image of three optical fibers, and (B) is a plan view of a basic image when there is no optical fiber. It is a schematic explanatory drawing which shows the conventional furnace monitoring apparatus.

  This will be described with reference to FIG. In the in-furnace monitoring apparatus 10 according to this embodiment, the sensor unit 12 that holds one or more optical fibers 11 as a sensor that detects, for example, the infrared ray 41 in the light of the flame that burns in the combustion furnace 40 is a rod unit. It is attached to the tip of 13. The middle of the rod portion 13 is inserted into the combustion furnace 40 and attached to the combustion furnace 40.

  As shown in FIGS. 2 (A) and 2 (B), for example, three optical fibers 11 having a diameter of about 1 mm are vertically arranged and held in the main body of the sensor unit 12. The tip of each optical fiber 11 is exposed, and the infrared ray 41 of the flame is guided from the tip surface.

  Of the above three, the upper optical fiber 11 is inclined obliquely upward at an angle of, for example, 15 °, the intermediate optical fiber 11 extends in the lateral direction, and the lower optical fiber 11 is, for example, 15 °. Tilt downward at an angle. Such an arrangement is intended to detect the flame in the furnace in a wide range in the vertical direction. The diameter of the main body of the sensor unit 12 is 15 mm, the length of the sensor unit 12 is 70 mm, and the length of the rod unit 13 is 5 m (meters).

Three transmission optical fibers 14 that propagate the flame infrared rays 41 guided by the optical fiber 11 of the sensor unit 12 are extended from the rear side of the rod unit 13 to the outside of the combustion furnace 40, It is connected. The process arithmetic unit 15 includes a PHD (photo detector), an amplifier, an arithmetic circuit, and the like (not shown). The light (infrared ray 41) propagated through each transmission optical fiber 14 is changed into a current (resistance value) by PHD, amplified by an amplifier, and then the state of flame light is monitored by an arithmetic circuit. For example, it is possible to determine (diagnose) whether there is a flame in the furnace, whether it is completely burned, or the like.
Based on the diagnosis result, the combustion state in the furnace can be controlled by stopping the operation of the combustion furnace 40 or strengthening the flame.

  In the sensor deterioration diagnosis device 20 of the present embodiment, in order to diagnose the transmittance of the optical fiber 11 of the sensor unit 12 in the in-furnace monitoring device 10, as shown by the dotted arrow in FIG. A cylindrical body 23 is attached to the rear end side of the sensor unit 12 extracted from the combustion furnace 40.

  As shown in FIG. 3 (A), the cylindrical body 23 has a cylindrical shape with a length of about 90 mm in this embodiment, and the tip side [the left end side in FIG. 3 (A)]. ], The rear end side of the sensor unit 12 is detachable. Note that the rear end surfaces of the three optical fibers 11 are exposed at the rear end surface of the sensor unit 12 as shown in FIG.

  Refer to FIG. 1 again. After the sensor unit 12 is attached to the cylindrical body 23, a diagnostic light source 21 is provided for allowing the diagnostic light 22 to enter the distal end surface of the optical fiber 11 exposed at the distal end of the sensor unit 12. In the present embodiment, the distance between the diagnostic light source 21 and the tip surface of the sensor unit 12 is about 20 mm.

  The diagnostic light source 21 desirably has a configuration that generates diagnostic light 22 that provides flat illumination with a spatially constant illuminance of light. Therefore, for example, the light from the diagnostic light source 21 can be reflected by using a reflector or the like to make the diagnostic light 22 with uniform brightness. Alternatively, as the diagnostic light source 21, a large number of LEDs (light emitting diodes) that emit light of blue, red, white, and the like can be arranged and reflected from the back surface using a reflector to obtain uniform brightness. . As described above, a surface light-emitting device that provides surface-emitting illumination can be used.

  This will be described in more detail. For example, the waveform 24 of the diagnostic light 22 having a spatially flat illuminance is represented by the light intensity (illuminance) at each position in the diameter direction of the diagnostic light 22 as shown in FIG. The light intensity increases from the outer peripheral side + R, -R of the diameter D of the light 22 toward the center O with a relatively steep gradient, and the parallel light having the same light intensity near the center, that is, the illuminance near the center is flat. It becomes area 25. Therefore, parallel light near the center is incident on the tip surface of the optical fiber 11.

Since the diameter of the sensor unit 12 is 15 mm, for example, the other region is covered with a cover or the like so that only parallel light near the center of the flat region 25 of the diagnostic light 22 is emitted. You may make it small so that shines.
As described above, the diagnostic light 22 having spatially uniform illuminance is required because, for example, the brightness irradiated to the three optical fibers 11 varies as shown in FIG. This is because the deterioration state of the optical fiber 11 cannot be properly compared.

  The diagnostic light source 21 is preferably a surface light emitting device using the above-described many LEDs. This is because halogen lamps and metal halide lamps are naturally deteriorated even if they are not used, but LEDs have a long life and have little deterioration over time.

On the rear end side of the cylindrical body 23, diagnostic light 22 emitted from the rear end surface of the optical fiber 11 exposed on the rear end surface of the sensor unit 12 is imaged, and the transmittance of the optical fiber 11 is diagnosed. An image diagnostic device 30 for displaying a diagnostic image 34 is provided.
As the diagnostic imaging apparatus 30, for example, a camera 31 (VTR) is provided as imaging means for imaging the diagnostic light 22. As shown in FIG. 3A, the camera 31 (VTR) includes, for example, a plurality of lenses 32 such as a macro lens and a telecentric lens. That is, the main body of the lens 32 is detachably attached to the rear end side of the cylindrical body 23.

  When the rear end side of the sensor unit 12 is attached to the distal end side of the cylindrical body 23 and the main body of the lens 32 is attached to the rear end side of the cylindrical body 23, the inside of the cylindrical body 23 becomes completely dark. Therefore, the diagnostic light 22 emitted from the rear end face of the optical fiber 11 becomes clear, and a diagnostic image 34 enlarged by the lens 32 is obtained by the camera 31 (VTR) as shown in FIG. be able to. For example, a plurality of diagnostic images 34 may be superimposed to increase the S / N.

A monitor 38 for displaying the diagnostic image 34 is provided for diagnosing the transmittance of the optical fiber 11 based on the diagnostic image 34.
As the lens 32, for example, a macro lens having a magnification factor of 0.75 is used, and the camera 31 (VTR) has an image pickup element of 1/2 inch to 1/3 inch, Contains hundred pixels.

The diagnostic image 34 will be described in more detail. When the optical fiber 11 is deteriorated, that is, when the deposit 42 is attached to the front end surface of the optical fiber 11 of the sensor unit 12, the brightness of the diagnostic light 22 that has propagated through the optical fiber 11 is reduced. As shown in FIG. 5A, the diagnostic image 34 detected at this time becomes dark and the luminance decreases.
Since the brightness of the diagnostic image 34 varies depending on the state of attachment of the deposit 42 on the tip surface of the optical fiber 11, the state of attachment of the deposit 42 can be diagnosed by the brightness of the diagnostic image 34. In general, the luminances of the diagnostic images 34A, 34B, and 34C of the three optical fibers 11 are different from each other.

A method for diagnosing (determining) the diagnostic image 34 will be described.
Ideally, a new optical fiber 11 is purchased and the brightness of the diagnostic image 34 in that case is used as a reference value. However, since the new optical fiber 11 is very expensive, a method of diagnosing in the current use state is adopted.

  As an example, the luminances of the three diagnostic images 34A, 34B, and 34C are compared with each other and relatively determined. For example, the diagnostic images 34A and 34B are compared, the diagnostic images 34B and 34C are compared, and the diagnostic images 34C and 34A are compared to obtain a relative absolute value, and then a “threshold value” is set. . The “threshold value” refers to the luminance of the diagnostic image 34 corresponding to the transmittance at which the optical fiber 11 cannot be used.

Whether or not to replace the three optical fibers 11 of the sensor unit 12 is determined based on whether or not the diagnostic images 34A, 34B, and 34C are below the “threshold value”. For example, if two of the three diagnostic images 34 can be used, the diagnosis is made (judgment) that they can be used as they are without replacement.
Further, when two of the three diagnostic images 34 cannot be used and the deterioration of one diagnostic image 34 is considerably advanced, it is diagnosed (determined) that it is necessary to replace it.
The above two examples are exemplifications of diagnostic criteria, and it is possible to determine in advance based on how the criteria for judgment are set in advance.

A method for diagnosing (determining) another diagnostic image 34 will be described.
As shown in FIG. 5B, a state in which the optical fiber 11 is not contained in the sensor unit 12 is taken in advance in an image, and this is set as one judgment reference basic image 39A, 39B, 39C. Since the basic images 39A, 39B, and 39C do not contain the optical fiber 11, the diagnostic light 22 itself is imaged and its luminance is set to 100%.

By comparing with the basic images 39A, 39B, and 39C at positions corresponding to the diagnostic images 34A, 34B, and 34C, it is possible to diagnose how much luminance each diagnostic image 34A, 34B, and 34C has. By setting the brightness of the “threshold value” in advance, the three optical fibers of the sensor unit 12 depend on whether or not the brightness of each diagnostic image 34A, 34B, 34C is lower than the “threshold value”. It is determined whether or not 11 is exchanged.
As a result, the transmittance of the optical fiber 11 of the sensor unit 12 based on the diagnostic image 34 enlarged on the screen of the monitor 38 by the method of diagnosis (judgment) of the diagnostic image 34 as described above is not required by an expert. Diagnosis can be made easily and accurately.

The image diagnostic apparatus 30 includes an image processing apparatus 33 that converts a diagnostic image 34 captured by the camera 31 into processing data such as luminance in order to automatically diagnose the deterioration state of the optical fiber 11. . Furthermore, the control apparatus 35 provided with the function for diagnosing the degradation state of the optical fiber 11 with the process data is provided.
Therefore, the diagnostic image 34 of the diagnostic light 22 captured by the camera 31 is converted into luminance processing data by the image processing device 33, and the processing data is analyzed and compared by the control device 35, whereby the optical fiber 11 is deteriorated. The condition is automatically diagnosed.

This will be described in more detail.
As described above, the brightness of the diagnostic image 34 changes according to the attached state of the deposit 42 on the tip surface of the optical fiber 11, so the attached state of the deposited matter 42 is diagnosed by the brightness of the diagnostic image 34. be able to. Therefore, the control device 35 is provided with an arithmetic device 36, and the arithmetic device 36 digitizes the luminance processing data.
As a diagnostic standard for determining whether or not the optical fiber 11 of the sensor unit 12 can be used, a “threshold value” is set in advance based on the diagnosis (judgment) method of the diagnostic image 34 as described above.

  In the diagnosis (judgment) methods of some of the diagnostic images 34 described above, the absolute value of the reference brightness and the “threshold value” are set without using the new optical fiber 11 with no deposit 42 attached. It explains about setting. As another method, the transmittance in a state where the new optical fiber 11 is used and the deposit 42 is not attached at all is set as an absolute value, and a “threshold value” is set in advance based on the absolute value. I can leave.

  The control device 35 is provided with a comparison / judgment device 37. In the comparison / judgment device 37, when the brightness of the diagnostic image 34 measured as described above falls below the “threshold value”, the optical fiber 11 is used. Is determined to be unusable (diagnostic). With this diagnosis, the corresponding optical fiber 11 is newly replaced. Alternatively, the sensor unit 12 is replaced with a new sensor unit 12.

  As described above, since it can be used almost immediately before the use limit without relying on so-called maintenance personnel's judgment, it is possible to reduce the cost of maintenance. Instead of simply diagnosing the diagnosis image 34 by a person, the brightness of the diagnosis image 34 can be converted into a numerical value and automatically diagnosed.

In addition, even if the brightness of the measured diagnostic image 34 is lower than the “threshold value” by giving the above “threshold value” a margin for the expiration date (raising the “threshold value” level), for example. It is also possible to determine the degree and range of the usable state at that time, not the unusable state.
In the above-described diagnostic imaging apparatus 30, the arithmetic unit 36 calculates how much the luminance of the diagnostic image 34 is different from the “threshold value”, and this calculated value becomes the “threshold value”. It is possible to predict how much use period is allowed to reach and reach the process operation device 15 with a feedback function.

From the above, it can be used until it almost reaches the “threshold value” without taking measures such as increasing the “threshold value”. In addition, since the deterioration information of the optical fiber 11 can be fed back to the in-furnace monitoring apparatus 10 in normal operation, it can be used almost immediately before the use limit. The above cost reduction can be achieved.

The present invention generates so-called combustion flames, such as boilers for thermal power plants, waste incinerators, blast furnaces related to steel and non-ferrous metals, coke ovens, aluminum reflectors, glass melting furnaces and various firing furnaces. It can utilize for the in-furnace monitoring apparatus used for the combustion furnace to do.

DESCRIPTION OF SYMBOLS 10 In-furnace monitoring apparatus 11 Optical fiber 12 Sensor part 13 Rod part 14 Transmission optical fiber 15 Process arithmetic unit 20 Sensor degradation diagnostic apparatus 21 Diagnostic light source 22 Diagnostic light 23 Cylindrical body 24 Waveform (of diagnostic light 22) 25 Flat area 30 Diagnostic imaging device 31 Camera (imaging means)
32 Lens 33 Image processing device 34, 34A, 34B, 34C Diagnostic image 35 Control device 36 Arithmetic device 37 Comparison judgment device 38 Monitor 39A, 39B, 39C Basic image 40 Combustion furnace 41 Infrared ray (flame light)
42 Deposits

Claims (8)

In order to extract light from the internal space of the combustion furnace to the outside of the combustion furnace, a rod part attached to the combustion furnace, a sensor part attached to the rod part, and held by the sensor part from the inside of the combustion furnace An in-furnace monitoring device comprising one or more optical fibers for introducing light and extracting the light to the outside, and a process operation device for inputting the light guided by the optical fiber, the transmittance of the optical fiber A sensor deterioration diagnosis device for diagnosing
A cylindrical body for attaching the rear end side of the sensor unit extracted from the combustion furnace,
A diagnostic light source for injecting diagnostic light into the distal end surface of the optical fiber exposed at the distal end of the sensor unit attached to the cylindrical body;
An image diagnostic apparatus that images diagnostic light emitted from the rear end face of the optical fiber exposed on the rear end face of the sensor unit and displays a diagnostic image for diagnosing the transmittance of the optical fiber;
Sensor deterioration diagnosis device comprising:   2. The sensor deterioration diagnostic apparatus according to claim 1, wherein the diagnostic light source is configured to generate diagnostic light that is flat illumination in which the illuminance of light is spatially constant.   The diagnostic imaging apparatus is a computing device that digitizes the brightness of a diagnostic image, and compares the measured brightness value calculated by the computing device with a preset threshold of brightness at which the optical fiber cannot be used. The sensor deterioration diagnosis apparatus according to claim 1, further comprising a comparison / determination apparatus that determines the transmittance of the optical fiber.   The diagnostic imaging apparatus calculates how much the luminance of the diagnostic image is different from the threshold value, and how much use time can be left until the calculated value reaches the threshold value. The sensor deterioration diagnosis apparatus according to claim 3, wherein the sensor deterioration diagnosis apparatus has a function of predicting the predicted value and feeding back the predicted information to a process operation apparatus for normal operation. A rod part attached to the combustion furnace for extracting light from the internal space of the combustion furnace to the outside of the combustion furnace, a sensor part attached to the rod part, and a cylindrical shape attached to the rear end side of the sensor part A body, one or more optical fibers for guiding light from the inside of the combustion furnace held by the sensor unit and taking it out to the outside, and a process arithmetic device for inputting the light guided by the optical fiber, In the in-furnace monitoring apparatus, the sensor deterioration which diagnoses the transmittance | permeability of the said optical fiber by attaching the rear-end side of the said sensor part removed from the said rod part extracted from the said combustion furnace to the said cylindrical body A diagnostic method,
A diagnostic light incident procedure for injecting diagnostic light into the distal end surface of the optical fiber exposed at the distal end of the sensor unit;
An imaging procedure in which diagnostic light that the diagnostic light that has entered the optical fiber propagates through the optical fiber and exits from the rear end surface of the optical fiber is imaged by an image diagnostic apparatus that is attached to the rear end side of the cylindrical body;
An image diagnostic procedure for diagnosing the transmittance of the optical fiber based on a diagnostic image acquired by the imaging procedure.   6. The method for diagnosing sensor deterioration in an in-furnace monitoring apparatus according to claim 5, wherein in the diagnostic light incident procedure, diagnostic light having flat illumination in which the illuminance of light is spatially constant is incident.   The diagnostic imaging procedure includes a procedure for judging the transmittance of the optical fiber by comparing the brightness of the diagnostic image obtained by imaging the diagnostic light with a preset threshold value of the brightness at which the optical fiber cannot be used. The sensor deterioration diagnosis method according to claim 5, wherein:   The diagnostic imaging procedure calculates how much the brightness of the diagnostic image is different from the threshold value, and how much time can be used until the calculated value reaches the threshold value. The method for diagnosing sensor deterioration according to claim 7, further comprising: a step of feeding back the predicted information to a process operation device for normal operation.

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