JP2005180973A - In-furnace measuring instrument - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an in-furnace measurement instrument capable of exact measurement, while preventing dirt from sticking to a noncontact instrument, in a system which can perform various measurement and cleaning through an in-furnace measurement opening. <P>SOLUTION: The in-furnace measuring instrument 10 is constituted that a noncontact measurement instrument 11 performs various measurement through the optical axis via a measurement opening 22 formed on a furnace wall and reflected by a metal mirror 12 arranged on a first cylindrical path 100 extending toward outside of the furnace along the axial line of the opening. An infrared window 13, arranged on the light incident path of the first cylindrical path 100 and a virgin gas feed means 15 for feeding the virgin gas on the opening side of the infrared window 13 are provided. The virgin gas feed means 15 are arranged around the light incident path. There is provided the stuck slag storage part 18 for storing stuck slag, by dropping the generated stuck slag, at the time of cleaning the opening, while preferably moving the metal mirror 12 and the infrared window 13 for cleaning. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an in-furnace measuring apparatus that performs various measurements including an in-furnace temperature and an in-furnace pressure from a measurement opening formed in a furnace wall, and in particular, various measurements are performed by a non-contact measuring instrument provided outside the furnace. The present invention relates to an in-furnace measuring apparatus.

  Heat treatment furnaces such as melting furnaces and incinerators that process wastes are monitored for operation by measuring the temperature and pressure in the furnace, the state of the furnace, etc. so that smooth operation is performed. In general, when performing various measurements, a measurement opening that communicates with the inside of the furnace is provided on the side wall of the furnace, and various measuring devices are inserted from this opening, or a method of non-contact measurement through the opening is used It has been. For example, when measuring the temperature in the furnace, there is a method of measuring the temperature in the furnace with a radiation thermometer installed outside the furnace through a measurement opening formed in the furnace wall. In addition, a method of visualizing and monitoring the situation inside the furnace using an infrared camera is also used.

  However, the measurement opening provided in the furnace wall has a problem that it narrows and closes with the operation of the furnace. The main reason for this is that dust, volatiles, etc. floating in the furnace melt in a high temperature atmosphere and adhere to the measurement opening which communicates with the outside of the furnace and has a relatively low temperature and solidifies. As described above, when the deposits are stacked on the measurement opening, the opening is narrowed or blocked, and various measurements cannot be performed accurately.

In view of this, a technique for removing deposits fixed to the in-furnace measurement opening is disclosed in Japanese Patent Laid-Open No. 11-83001 (Patent Document 1) and the like. In Patent Document 1, it is detected that the clinker is attached to the measurement opening of the incinerator, and if the presence of the clinker is recognized, the purge gas is pumped and removed, or the clinker is pushed down and removed by the cleaning means. The device is described.
Japanese Patent Application Laid-Open No. 11-44581 (Patent Document 2) discloses a device that performs non-contact temperature measurement using a radiation thermometer or the like, and removes the fused material by dropping it on the axis of the furnace wall opening. The radiation thermometer is installed by bending the collimation direction by providing a cleaning rod to be mounted and providing a mirror outside the furnace facing the opening. Thereby, while being able to remove the fusion | melting matter of an opening part, a non-contact temperature measurement can be performed correctly irrespective of presence of a cleaning stick.

Further, in Japanese Patent Application Laid-Open No. 2001-349535 (Patent Document 3), the main passage communicating with the measurement opening of the incinerator is disposed so as to be able to advance and retreat in a crossing path between the main passage and the measurement passage branching. And a non-contact type temperature measuring means provided in the measurement path. During cleaning, the light refracting means is retracted and the clinker is removed by the cleaning means. There is provided an apparatus for performing non-contact temperature measurement via a means.
According to this, since cleaning and temperature measurement can be performed alternately via the main passage, the entire apparatus can be made compact.

Japanese Patent Laid-Open No. 11-83001 Japanese Patent Laid-Open No. 11-44581 JP 2001-349535 A

As described above, the measurement opening formed in the furnace wall may be narrowed and blocked by melting and adhering dust and volatilized matter scattered in the furnace and accumulating. If the opening is narrowed or closed, the measurement field of view is gradually lost, a measurement error occurs and accurate measurement cannot be performed, and the furnace cannot be operated smoothly.
Therefore, accurate measurement is possible by removing the deposits in the measurement openings as in Patent Documents 1 to 3. However, as in Patent Document 1, it is difficult to remove the deposits by pumping a purge gas because the deposits are firmly melted and fixed. And the device is selectively moved to the opening side and used, which increases the size of the apparatus and complicates the control.

Further, in Patent Document 2, a hole is formed in the center of the mirror, and since a vibration isolator is provided at the tip of the cleaning rod inserted from here, it is difficult to ensure the field of view of the radiation thermometer. It is. Further, in Patent Documents 2 and 3, since the light refracting means and the non-contact type temperature measuring means communicate with the inside of the furnace, particles adhere and become dirty due to diffusion of the gas in the furnace, and the radiated light is absorbed or scattered. Measurement errors will occur. Furthermore, dirt may adhere to the non-contact temperature measuring means due to falling objects from the cleaning means during cleaning, and accurate measurement may not be performed. In particular, when applied to a furnace containing a large amount of dust, volatiles, etc. in the furnace gas, such as a melting furnace, dirt is likely to adhere and the lens surface of the non-contact temperature measuring means must be frequently cleaned. Don't be.
Therefore, in view of the above-mentioned problems of the prior art, the present invention can perform non-contact measurement and cleaning with a miniaturized apparatus, and prevents dirt from adhering to the non-contact measurement device, thereby enabling accurate measurement. An object of the present invention is to provide an in-furnace measuring apparatus that can be performed.

Therefore, in order to solve this problem, the present invention provides:
In the in-furnace measuring device that performs various measurements with a non-contact measuring instrument through an optical axis that is refracted by a refracting means disposed on the outside of the furnace on the axis of the opening through the opening for measurement formed in the furnace wall,
A light transmission window disposed so as to face the refraction means on a light incident path from the measurement opening toward the refraction means, and a purge gas supply means for supplying a purge gas to the opening-side surface of the light transmission window; The purge gas supply means is arranged around the light incident path.

  Thus, by sealing the refracting means with the light transmitting window and isolating it from the furnace atmosphere, it is possible to prevent the refracting means from being contaminated and causing measurement errors. In addition, since purge gas is supplied to the opening side of the light transmission window, it is possible to prevent contamination due to adhesion of dust and volatiles flowing from the inside of the furnace, and to ensure a sufficient measurement visual field. Measurement is possible. In this invention, various measurements include, for example, furnace temperature measurement, fire wall temperature measurement, and analysis of received infrared rays and the like to convert the image and detect the furnace condition as an image.

Further, the refraction means and the light transmission window are integrated into a light refraction unit, and the light refraction unit has a retreat means that can move above the axis of the measurement opening, and when the light refraction unit is retracted, It is characterized in that an adhering soot storage unit for dropping and storing the adhering soot generated by cleaning the measurement opening is provided below the axis.
According to this invention, by moving the photorefractive unit above the axis, the photorefractive unit does not become contaminated through the furnace during cleaning. Furthermore, by providing the deposit bag storage unit, it is possible to prevent the cleaning unit from being hindered from being hindered by the deposit bag generated at the time of cleaning or from being damaged.
At this time, it is preferable that a sealing means is provided below the light refraction unit so that the light refraction unit is isolated from the cleaning area when the measurement opening is cleaned. Thereby, the wrinkle of the deposit | attachment which peeled by cleaning does not adhere to a photorefractive unit.

  Further, the light transmission window is formed of an infrared transmission window material, and the refraction means is formed of metal or quartz glass, and the non-contact measuring instrument is a radiation thermometer or a long wavelength infrared camera. It is preferable to do. According to this, various measurements can be performed via infrared rays even in an atmosphere in a furnace where there are many scattered matters such as dust, and the light receiving rate in the non-contact measuring instrument can be improved by using each of the materials. .

  Furthermore, in these inventions, it is preferable that the in-furnace measuring device is installed in a melting furnace. In the melting furnace, there are many scattered matters such as dust and volatile matter in the gas in the furnace, and when the refracting means is exposed and installed, dirt is immediately attached and measurement becomes impossible. Therefore, by applying the above-described invention to a melting furnace, accurate measurement can be performed even in a melting furnace with a lot of scattered matter, which is preferable.

As described above, according to the present invention, the refracting means is sealed by the light transmission window to be isolated from the furnace atmosphere, and a purge gas is supplied to the opening side surface of the light transmission window. In addition, it is possible to prevent contamination due to adhesion of dust and volatile matter flowing from the inside of the furnace to the light transmission window, and to ensure a sufficient measurement visual field, thereby enabling accurate measurement.
In addition, the light refraction unit can be moved above the axis, and the light refraction unit and the cleaning area are separated from each other at the time of cleaning, so that the light refraction unit is not contaminated through the furnace. Furthermore, by providing the deposit bag storage part, it is possible to prevent the cleaning unit from being hindered from being smoothly driven due to the deposit bag generated at the time of cleaning or from being damaged.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in this embodiment are not intended to limit the scope of the present invention unless otherwise specified, but are merely illustrative examples. Not too much.
In this embodiment, the case where the in-furnace measuring device is applied to a plasma melting furnace will be described as an example. However, the present invention is not limited to this, and various other melting furnaces such as a burner melting furnace, an electric resistance melting furnace, etc. It can also be applied to incinerators.

  First, the plasma melting furnace 20 in which the in-core measuring device 10 according to the present embodiment is installed will be described with reference to FIG. The plasma melting furnace 20 has a main electrode 24 penetrating through the furnace lid, and a furnace bottom electrode 25 disposed on the furnace bottom facing the main electrode 24, and a direct current is provided between these electrodes. A voltage is applied to generate a plasma arc 26 to heat and melt an object to be melted such as incineration ash. The molten material to be melted is separated into a molten slag 27 and a molten metal 28 due to a difference in specific gravity, accumulated in a layered manner at the bottom of the furnace, and discharged by overflow.

The plasma melting furnace 20 includes various measuring instruments for smooth and proper operation, and performs operation and in-furnace monitoring based on the measured values obtained thereby. The measurement items used as indices include furnace temperature, fire wall temperature, slag temperature, furnace pressure, slag melting condition, arc flame condition (image recognition), and the like.
In this embodiment, items that can be measured in a non-contact manner are targeted. A measurement opening 22 that penetrates the inside and outside of the furnace is formed in the furnace wall 21, and the measuring device 10 that detects the measurement item is installed outside the furnace. The measuring device 10 includes a non-contact measuring device 11 that performs various measurements. The measuring device 11 detects, for example, radiant infrared rays emitted from the furnace and calculates a temperature based on the detected amount of infrared rays. Or a long-wavelength infrared camera that analyzes received infrared radiation and converts the image. In addition, the measurement in a present Example includes the case where an image is acquired with an infrared camera etc.
Then, based on the output of these measuring devices 10, the amount of molten material input, the amount of slag output, the DC power supply voltage value, the arc length, etc. are controlled so as to achieve a suitable operating state.

  The furnace 23 is maintained in a high temperature atmosphere of about 1100 ° C. or more by the plasma arc 26, and volatilized substances and dust containing chlorides and heavy metals such as low boiling point sodium and potassium generated from the molten material to be melted. Etc. 31 are in a floating state, and these chlorides and the like are cooled by the furnace wall and deposited as deposits 30 on the furnace wall. In particular, since the temperature near the opening 22 communicates with the outside of the furnace, the temperature drop is significant. When the molten deposit 30 flows down to the vicinity of the opening, the deposit is cooled and solidified, narrowing and closing the opening 22. Therefore, there is a possibility that the field of view of the non-contact measuring instrument 11 is lost, or dirt is attached to the lens of the measuring instrument 11 and accurate measurement cannot be performed.

Therefore, in this embodiment, the in-furnace measuring apparatus 10 shown in FIGS. 1 and 2 is installed on the furnace wall 21 to perform accurate measurement. FIG. 1 is a side sectional view of an in-furnace measuring apparatus at the time of measurement according to an embodiment of the present invention, and FIG. 2 is a side sectional view of the in-furnace measuring apparatus at the time of cleaning. In this embodiment, infrared light is used as an example, but the present invention is not limited to this, and other suitable light such as microwaves is also used.
1 and 2, the main configuration of the in-furnace measuring apparatus 10 according to the present embodiment includes a non-contact measuring instrument 11, a metal mirror 12, an infrared window 13, and a purge gas supply that seals the infrared window 13. And means 15.

A first cylindrical path 100 extending outside the furnace is provided on the same axis as the measurement opening 22, and a second cylindrical path 200 having an intersection with the cylindrical path 100 outside the furnace is further provided. Is provided. Both of these cylindrical paths 100 and 200 are sealed from the outside so that the gas in the furnace, dust, etc. do not leak out of the furnace.
The non-contact measuring instrument 11 may be a radiation thermometer, a long wavelength infrared camera, or the like that is provided at the upper end of the second path 200 and receives infrared rays and performs various measurements.

The metal mirror 12 is installed at a predetermined angle at the intersection so as to face the measurement opening 22, and radiated light transmitted from the measurement opening 22 through the cylindrical path 100 is bent by the mirror 12. The non-contact measuring instrument 11 is transmitted. The metal mirror 12 is configured to be slidable on the second cylindrical path 200, and is positioned at the intersection during measurement, and retracts upward from the intersection during cleaning.
When using infrared rays as in the present embodiment, it is preferable to improve the light receiving rate of the non-contact measuring instrument 11 by using a metal mirror that can minimize the diffusion of infrared rays. In this embodiment, the mirror 12 is made of a metal material, but quartz glass or the like can also be used.

The infrared window 13 is disposed on the incident path from the measurement opening 22 toward the metal mirror 12 so as to face the metal mirror 12. The infrared window 13 is preferably made of a material having high infrared transmittance such as ZnSe or Ge. Similar to the metal mirror 12, the infrared window 13 is also configured to be slidable, and is positioned at the intersection during measurement, and retracts above the second cylindrical path 200 above the intersection during cleaning. .
The metal mirror 12 and the infrared window 13 may be integrated to form a light refraction unit, and are retracted upward together during cleaning. At this time, it is preferable to provide the sealing means 14 at the lower part of the light refraction unit, so that the first path 100 and the light refraction unit are isolated at the time of cleaning, and the unit is contaminated by fouling. To prevent.

  The purge gas supply means 15 has a nozzle 15 a that is disposed around the light incident path and ejects the purge gas 16 toward the furnace side window surface of the infrared window 13. The nozzle 15a is configured to eject a purge gas stored in a flange portion provided around the first cylindrical path 100, and the nozzle opening is directed to the furnace-side window surface. In this way, the purge window is ejected and sealed on the furnace side window surface communicating with the inside of the furnace so that the infrared window 13 is not contaminated and the mirror 12 is shielded by the infrared window 13. It is possible to prevent dirt from adhering to the mirror 12, and the infrared light receiving rate in the radiation thermometer 11 is improved, thereby enabling accurate measurement.

Furthermore, in the present embodiment, the cleaning rod 17 for dropping and removing the deposit 30 hanging from the measurement opening 22 can also be provided. The cleaning rod 17 is inserted from the furnace outer end of the first cylindrical path 100, is configured to be able to reciprocate on the first cylindrical path 100, and deposits 30 hanging from the measurement opening 22. Is pushed down by the rod 17.
At this time, the deposit bag storage part 18 is provided below the second cylindrical path 200. This is because the adhering matter fixed to the measurement opening 22 and the inner surface of the first cylindrical path 100 is scraped off by the reciprocating movement of the cleaning rod 17 and is accumulated in the path 100 to reciprocate the rod. Therefore, by providing the deposit bag storage part 18, the deposit bag 19 is removed from the path 100, and a failure of the cleaning device can be prevented.
Further, during cleaning, the cleaning rod 17 is moved above the deposit bag storage unit 18 and the cleaning rod 17 is rotated here, whereby the deposit rod 19 falls into the deposit bag storage unit 18. Since they are accumulated, the inside of the second cylindrical path 200 is not contaminated and effective.

The cleaning rod 17 may be provided with a rotation mechanism so as to reciprocate while rotating. Thereby, a hard deposit can also be removed reliably. In addition, the cleaning rod 17 can be provided with a mechanism that bends in the middle of the shaft. This can be suitably applied to the measurement opening 22 or the first cylindrical path 100 having different diameters. By providing both the rotating mechanism and the bending mechanism at the same time, the shaft is bent when the reciprocating motion reaches a position where the diameters are different, and the deposit on the inner surface is reliably cleaned by rotating and rotating the shaft. Can be removed.
As another method, the cleaning rod 17 may be inserted at an angle and moved to the next position after reciprocating.

Here, the operation of the present embodiment will be described. At the time of in-furnace measurement, the cleaning rod 17 is retracted backward as shown in FIG. 1, and the photorefractive unit including the metal mirror 12 and the infrared window 13 is moved. The infrared rays emitted from the furnace after moving to the intersection are transmitted through the infrared window 13, bent by the metal mirror 12, and detected by the non-contact measuring instrument 11 through the optical path A. Then, based on the detected amount of infrared rays or the like, the temperature in the furnace is calculated or the image is converted so that the state in the furnace can be visually recognized.
On the other hand, during cleaning, the photorefractive unit is retracted upward, and the cleaning rod 17 is reciprocated while appropriately rotating, and the deposit 30 hanging from the measurement opening 22 and the opening 22 and the first cylindrical path The deposit on the inner surface of 100 is removed and cleaned. The removed deposits 19 are collected by dropping into the deposits storage unit 18 and discarded.

As described above, the metal mirror 12 is sealed by the infrared window 13 to be isolated from the furnace atmosphere, and the purge gas is supplied to the surface on the measurement opening 22 side. The outer window 13 can be prevented from being contaminated by dust or volatile matter flowing from the inside of the furnace, and a sufficient measurement visual field can be secured, thereby enabling accurate measurement.
Further, by moving the light refracting unit above the axis, the light refracting unit does not become contaminated through the furnace during cleaning. Further, by providing the deposit bag storage unit 18, it is possible to prevent the cleaning unit from being hindered from being prevented from being smoothly driven due to the deposit bag generated at the time of cleaning or from being damaged.

  In this embodiment, a means for controlling the amount of purge gas blown to the infrared window may be provided so as to purge the infrared window and purge the measurement opening. The amount of dust and the like that enters can be reduced, and the number of cleanings can be reduced.

It is side surface sectional drawing of the measuring device in a furnace at the time of the measurement which concerns on the Example of this invention. It is side surface sectional drawing of the measuring device in a furnace at the time of the cleaning which concerns on the Example of this invention. 1 is an overall configuration diagram of a melting furnace including an in-furnace measuring device according to an embodiment of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Measuring apparatus 11 Non-contact measuring device 12 Metal mirror 13 Infrared window 14 Sealing means 15a Nozzle 16 Purge gas 17 Cleaning rod 18 Deposited soot storage part 19 Deposited soot 21 Furnace wall 22 Measurement opening 23 Furnace 30 Deposited

Claims (6)

In the in-furnace measuring device that performs various measurements with a non-contact measuring instrument through an optical axis that is refracted by a refracting means disposed on the outside of the furnace on the axis of the opening through the opening for measurement formed in the furnace wall,
A light transmission window disposed so as to face the refraction means on a light incident path from the measurement opening toward the refraction means, and a purge gas supply means for supplying a purge gas to the opening-side surface of the light transmission window; An in-furnace measuring apparatus characterized in that the purge gas supply means is disposed around the light incident path.   The refraction means and the light transmission window are integrated into a light refraction unit, and the light refraction unit has retreat means that can move above the axis of the measurement opening, and the measurement is performed when the light refraction unit is retracted. The in-furnace measuring device according to claim 1, further comprising a deposit bag storage unit for dropping and storing the deposit bag generated by cleaning the opening for opening.   The in-furnace measuring device according to claim 1 or 2, wherein the light transmitting window is formed of an infrared transmitting window material, and the refracting means is formed of metal or quartz glass.   The in-furnace measuring apparatus according to claim 1 or 2, wherein the non-contact measuring instrument is a radiation thermometer or a long wavelength infrared camera.   The in-furnace measuring device according to claim 2, wherein a sealing means is provided below the light refraction unit, and the light refraction unit is isolated from a cleaning area when the measurement opening is cleaned.   An in-furnace measuring apparatus, wherein the in-furnace measuring apparatus according to any one of claims 1 to 5 is installed in a melting furnace.

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