JPH07140400A - Monitor device for inside of blast furnace - Google Patents

Abstract

PURPOSE:To provide the monitor device for the inside of a blast furnace capable of recognizing the state of the dark point in this furnace according to the state and condition of the gases in the blast furnace. CONSTITUTION:This monitor device 1 has an image pickup device 5 for picking up the image of the state in the blast furnace 2. This image pickup device 5 has a sensitivity to rays of visible and near IR regions. The image pickup device 5 is provided with a scanning time control means 7. The image pickup device 5 has a sensitivity to rays of a wavelength of 0.7 to 1.1mum. The image pickup device 5 is provided with a photodetected wavelength selecting means 10. The monitor device 1 is provided with an illuminating device 6. This illuminating device 6 is provided with an illuminating light wavelength selecting means 17 for selecting the wavelength of the rays to be cast to the illuminating device 6 in a range form 0.7 to 1.1mum.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a monitoring device for monitoring the condition inside a blast furnace for producing pig iron from iron ore.

[0002]

2. Description of the Related Art In a blast furnace for producing pig iron from iron ore, continuous operation is carried out by successively introducing iron ore and cokes from a furnace mouth. In order to carry out this continuous operation stably, it is preferable to charge the iron ore and coke so as to form a mortar-shaped hole having the lowest central portion in the furnace, for which iron ore and The coke is charged according to a predetermined stacking pattern designed so that a certain particle size is arranged at a predetermined position in the furnace.

However, since the charged iron ore and cokes are constantly moving toward the central bottom of the mortar-shaped hole, it is difficult to maintain the stacking pattern as designed, and the inside of the blast furnace is difficult to maintain. Problems such as a blow-through phenomenon in which the gas generated in 2) suddenly blows upward from around the iron ore and cokes are likely to occur.

Therefore, conventionally, an image pickup device such as a television camera used for monitoring the state of the dark place in the furnace of the blast furnace is known. As such an image pickup device, the present applicant has already proposed a device including a furnace monitoring camera 31 and an illumination device 32 shown in FIG. 3 (see Japanese Patent Application No. 3-315622). The image pickup device includes an in-furnace monitoring camera 31 for monitoring the state of the stacking pattern 5 in the furnace through a window portion 4a formed of a small hole provided in the peripheral wall 3 of the furnace opening 2, and a camera 31 for monitoring the inside of the furnace. Through the window portion 4b formed of a small hole provided,
The illumination device 32 illuminates the field of view of the in-furnace monitoring camera 31.

The in-furnace monitoring camera 31 comprises a short-focus wide-angle lens system 33 provided behind the window 4a, and an image pickup device 34 having sensitivity in the infrared region. The illumination device 32 includes a short-focus wide-angle lens system 35 provided behind the window portion 4b and an infrared light source 36.

According to the image pickup apparatus, since the field of view of the furnace monitoring camera 31 having sensitivity in the infrared region is illuminated by using the illuminating device 32 for illuminating infrared rays, the infrared rays can be used as dust generated in the furnace port 2. A clear image can be obtained by less scattering and by reducing halation due to a temperature difference between a hot object and a cold object. Therefore, according to the in-furnace monitoring camera 31, when an undesirable change occurs in the particle size and distribution of iron ore and cokes in the furnace, or when the gas blow-through occurs at an unexpected position, the position Since the iron ore and coke are charged in that position, it is easy to maintain and manage the stacking pattern 5.

Although the in-furnace monitoring camera 31 can grasp the surface condition of the iron ore and cokes charged by the stacking pattern 5 when the dust generated in the furnace opening 2 is relatively small. , It is not possible to understand the reaction status related to the distribution of iron ore and cokes in the blast furnace. Therefore, unless a situation such as blow-by of gas occurs, it is impossible to take necessary measures to maintain the stacking pattern 5. Therefore, in order to carry out the continuous operation of the blast furnace more stably, it is desired to grasp the reaction status inside the blast furnace.

The gas generated in the blast furnace is always the furnace port 2
It is known that the spouting is closely related to the reaction status in the blast furnace. That is, it is considered that the sudden blow-through is due to a sudden increase in the generation amount of the gas due to an abnormal reaction or the like occurring in the blast furnace.
If the state of the gas ejected to the furnace port 2 can be grasped, it is considered that measures can be taken in advance to deal with situations such as blow-by of the gas, and more stable operation is possible.

However, as described above, it is difficult for the furnace monitoring camera 31 having sensitivity in the infrared region to grasp the state of the gas.

Further, in the furnace monitoring camera 31, the furnace mouth 2
When a large amount of dust is generated in the interior, the dust is generated by the illumination device 32.
There is an inconvenience that the optical path of the infrared light illuminated from the inside may be blocked and the visual field of the furnace monitoring camera 31 may not be sufficiently illuminated.

[0011]

DISCLOSURE OF THE INVENTION The present invention eliminates the above-mentioned inconvenience, and can grasp the state of the gas in the blast furnace and also grasp the state of the dark place in the furnace depending on the situation. An object of the present invention is to provide a monitoring device in a blast furnace.

[0012]

The inventors of the present invention have conducted extensive studies on the state of the gas in the blast furnace, and as a result, the gas itself is contained in the gas although it cannot be detected by human eyes. Since the fine particles emit light rays in the visible to near-infrared region because they are heated in the blast furnace, it was found that the behavior of the gas flow can be grasped by catching the fine particles by utilizing these light rays. Further, the visible to near-infrared ray, since a small amount of dust is transmitted through the furnace even when a large amount of dust is present in the furnace,
The present invention has been completed by finding that an image having sufficient brightness for observing a dark place in a furnace can be obtained by increasing the scanning time of the image pickup device for capturing the fine particles. Incidentally, the phenomenon that the light rays in the visible to near-infrared region are slightly transmitted through the dust,
It is explained by the Lambert-Beer law for light transmission and the Mie scattering theory for light scattering.

Therefore, the monitoring device in the blast furnace of the present invention is
In a monitoring device in a blast furnace equipped with an imaging device for imaging the state inside the blast furnace, the imaging device is sensitive to light rays in the visible to near-infrared region, and controls the scanning time of the imaging device. It is characterized in that a scanning time control means is provided.

The image pickup device is sensitive to light having a wavelength of 0.7 to 1.1 μm in order to receive light in the visible to near-infrared region emitted by the fine particles heated in the blast furnace. Is preferred. The imaging device has a wavelength of 0.7
When it has sensitivity to visible light of μm or less, it cannot receive light due to scattering reflection by the fine particles,
When it has a sensitivity to infrared rays of 1.1 μm or more, the light rays emitted by the fine particles are too bright and cause halation,
It is not possible to accurately grasp the image of the fine particles.

Further, the monitoring device of the present invention is characterized in that it comprises light-receiving wavelength selection means for selecting the wavelength of the light beam received by the image pickup device.

Further, the monitoring device of the present invention is characterized in that an illumination device for illuminating the inside of the blast furnace is provided.
The illumination device accurately selects the image of the fine particles and selects the wavelength of the light to be illuminated in the range of 0.7 to 1.1 μm in order to facilitate observation of the dark place in the furnace. Means are provided.

[0017]

According to the monitoring device in the furnace of the blast furnace of the present invention, since the image pickup device is sensitive to the light rays in the visible to near-infrared region, the visible to near-infrared region emitted by the fine particles heated in the blast furnace. An image of the fine particles is obtained by receiving the rays of light, and the behavior of the gas flow is grasped through the fine particles.

Further, according to the monitoring device for the inside of the blast furnace of the present invention, the scanning time control means is provided in the imaging device and the scanning time of the imaging device is adjusted according to the situation so that the state of the fine particles can be confirmed. The observation and the dark place in the furnace are switched. That is, when the scanning time is short, the fine particles are mainly observed, but by increasing the scanning time, even when a large amount of dust is present in the furnace, the visible to near-infrared rays that slightly pass through the dust are transmitted. The light rays in the area are accumulated in the image pickup device, and an image having sufficient brightness to observe the dark place in the furnace is obtained.

In the monitoring device in the blast furnace according to the present invention, the image pickup device is sensitive to a light beam having a wavelength of 0.7 to 1.1 μm, so that the image of the fine particles can be accurately grasped, and When a large amount of dust is present in the furnace, light rays of the wavelength that slightly pass through the dust are likely to be accumulated in the imaging device.

Further, in the monitoring apparatus of the present invention, the wavelength of the received light beam can be selected according to the state of the fine particles by providing the image pickup device with the light receiving wavelength selecting means, and the image of the fine particles under a specific condition can be obtained. More accurately understood.

Further, in the monitoring apparatus of the present invention, by providing an illuminating device for illuminating the inside of the blast furnace, it becomes easy to observe the fine particles and the dark place in the furnace even when the amount of light in the blast furnace is insufficient. The illumination device is provided with an illumination wavelength selection unit that selects the wavelength of the light to be illuminated in the range of 0.7 to 1.1 μm, so that the fine particles and the dark place in the furnace can be easily observed.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The monitoring device in a blast furnace according to the present invention will be described in more detail with reference to the accompanying drawings. Figure 1
2 is an explanatory sectional view of a blast furnace in which the monitoring device of the present invention is installed, and FIG. 2 is an explanatory sectional view of the illumination device of FIG.

As shown in FIG. 1, the monitoring device 1 of the present embodiment.
Is a window portion 4a formed of a small hole provided in the peripheral wall 3 of the furnace opening 2.
Via the camera for in-furnace monitoring having a sensitivity to a light beam having a wavelength of 0.7 to 1.1 μm in the visible to near-infrared region for monitoring the state in the furnace, and a small camera provided on the peripheral wall 3 of the furnace opening 2. An illumination device 6 for illuminating the field of view of the in-furnace monitoring camera 5 through a window 4b formed of a hole. The in-reactor monitoring camera 5 is provided with a scanning time control device 7.

The scanning time control device 7 is 1/30 to 1/15 seconds per frame when observing the particles in the furnace with the camera 5 for monitoring the inside of the furnace, and 1 per frame when observing the dark place in the furnace. The scanning time is controlled to be / 30 to 1/10 seconds.

The furnace monitoring camera 5 is, as shown in FIG.
A short-focus wide-angle lens system 8 provided behind the window 4a
And an image pickup element 9 having a sensitivity to a light beam having a wavelength of 0.7 to 1.1 μm, and a light receiving element capable of selecting a wavelength in the range of 0.7 to 1.1 μm between the wide-angle lens system 8 and the image pickup element 9. A wavelength selection device 10 is provided.

The light receiving wavelength selection device 10 is provided with a plurality of optical filters, and the wavelengths within the above range can be arbitrarily selected by exchanging the optical filters. By providing the optical filter that selectively transmits an arbitrary wavelength range of 0.7 to 1.1 μm, it is possible to easily observe the fine particles in the furnace and the dark place in the furnace. . As such an optical filter,
Filters for normal cameras can be used.

By disposing the wide-angle lens system 8 so that its focal point is located at the center of the window portion 4a, the camera 5 for monitoring the inside of the furnace can cover a wide range of the inside of the furnace through the window portion 4a which is a small hole.
Can be the field of view. As the wide-angle lens system 8,
For example, viewing angle 78 °, focal length 150 mm, aperture 13
The one with 0 mm is used, and the illumination range can be wide angle of 70 ° or more.

Further, the camera 5 for monitoring the inside of the furnace is provided with a seal body 12 having a seal glass 11 for sealing the window 4a between the window 4a and the wide-angle lens system 8, and a pipe 13 is provided from a side surface of the seal body 11. The purge gas may be introduced and ejected via the. By doing so, the purge gas introduced into the seal body 12 is ejected from the window portion 4a, so that iron ore and coke dust, metal vapor such as zinc, and steam generated in the furnace during the operation of the blast furnace. And the like can be prevented from entering the furnace monitoring camera 5,
Since the surface of the seal glass 11 can be kept clean, the optical path of the light beam received by the furnace monitoring camera 5 is secured.

Further, in the furnace monitoring camera 5, a shut-off shutter 14 for opening and closing the window 4a is slidably provided by a cylinder (not shown) between the seal body 12 and the peripheral wall 3, and the iron ore is used. The window portion 4a can be closed when there is a risk that the sealing glass 11 is contaminated by dust such as stones and cokes.

As shown in FIG. 1, the illumination device 6 has a window portion 4b.
The wide-angle lens system 15 and the light source 16 which are provided behind the lens and have a short-focus wide-angle lens system 15 and a light source 16 such as a halogen lamp capable of illuminating light rays in the visible or infrared region.
And an illumination wavelength selection device 17 capable of selecting a wavelength in the range of 0.7 to 1.1 μm.

By disposing the wide-angle lens system 15 so that its focal point is located at the center of the window 4b, it is possible to illuminate a wide range in the furnace through the window 4b formed of small holes. The wide-angle lens system 15 has, for example, a viewing angle of 78 ° and a focal length of 150, as in the furnace monitoring camera 5.
It is possible to use a lens having a diameter of 130 mm and a diameter of 130 mm, and it is possible to illuminate a range which is a visual field of the in-furnace monitoring camera 5 with a wide angle of 70 ° or more as an imaging target range.

The illuminating wavelength selecting device 17 has the same structure as that of the receiving wavelength selecting device 10 and can arbitrarily select the wavelength in the above range.

Further, the illumination device 6 is provided with a camera 5 for monitoring inside the furnace.
Similarly, the window portion 4b is provided between the window portion 4b and the wide-angle lens system 14.
By providing a seal body for sealing b, and introducing a purge gas, dust of iron ore and cokes generated in the furnace during the operation of the blast furnace, metal vapor such as zinc, steam, etc. can enter the equipment. And the optical path of the light beam illuminated from the illumination device 6 is secured. Further, a blocking cylinder for opening / closing the window 4b is slidably provided between the seal body and the peripheral wall 3 so that the window 4b can be closed.

Next, the operation of the monitoring device 1 of this embodiment will be described.

Inside the blast furnace, the iron ore and cokes charged from the furnace port 2 are reacting with each other with high heat, and the gas generated by the reduction reaction of the iron ore is introduced from the periphery of the iron ore or cokes on the stacking pattern surface. It blows up to form a gas flow. Although the gas flow itself cannot be visually detected, the gas flow contains fine particles with a particularly small particle size among the dust generated in the blast furnace, and such fine particles are generated in the blast furnace. Since it is heated to a high temperature, it emits light by itself.

The light rays emitted from the fine particles are in the visible to near-infrared region, and the wavelength thereof is in the range of 0.7 to 1.1 μm. Since the in-furnace monitoring camera 5 includes the image sensor 9 having a sensitivity in the wavelength range, an image of the fine particles can be obtained by receiving the light beam emitted by the fine particles.
Then, the behavior of the gas flow is grasped through the image of the fine particles.

In the monitoring apparatus 1 of the present embodiment, normally all the light rays emitted by the fine particles are macroscopically observed within the wavelength range, but depending on the particle diameter of the fine particles and the heating state, only the light rays of a specific wavelength may be emitted. In such a case, it is possible to select the wavelength of the light beam to be received by the light receiving wavelength selecting means 10 and microscopically observe the behavior of the fine particles only from the light beam of the specific wavelength.

When a sufficient amount of light for observing fine particles cannot be obtained in the furnace port 2, a sufficient amount of light is obtained by illuminating the field of view of the in-furnace monitoring camera 5 with the illumination device 6. To be Since the light beam illuminated from the illumination device 6 is reflected by the fine particles and received by the image pickup device 9, it is preferable that the wavelength is within the sensitivity range of the image pickup device 9. Further, only fine particles in a specific temperature state are microscopically observed. When observing the light, the illumination wavelength selection means 17 selectively illuminates a light beam having a wavelength selected according to the wavelength of the light beam emitted by the fine particles in the specific temperature state.

When observing the fine particles with the in-furnace monitoring camera 5, the scanning time control device 7 adjusts the scanning time according to the flow velocity of the fine particles. That is, when the flow velocity of the fine particles is about 1 m / sec, the scanning time per frame is 1/15 seconds, and when the flow velocity of the fine particles is about 2 m / sec, the scanning time per frame is 1/30. Adjusted to be seconds.

When the scanning time is adjusted according to the flow velocity of the fine particles, when the amount of dust in the furnace is large, it is emitted or reflected from a dark place in the furnace such as iron ore or coke on the surface of the stacking pattern. Since the generated light is blocked by the dust, it is hardly received by the image sensor 9, and an image with sufficient brightness cannot be obtained in the dark place in the furnace. However, since the light rays from the dark place in the furnace are slightly transmitted through the dust particles, by increasing the scanning time per frame, the amount of light received and accumulated in the image sensor 9 increases.
Images with sufficient brightness for observation can be obtained.

The above-mentioned effect is particularly remarkable when the dark place in the furnace is located at a position lower than the dust like the surface of the stacking pattern. This is because the dust has a relatively low temperature and does not emit light by itself, and the black body simply passes through the optical path of light rays emitted or reflected from the dark place in the furnace at a high speed. Is. In the above state, the flow velocity of the fine particles is higher than the scanning time per frame, which is considered to be the same as the principle that an image can be seen even if the optical path is blocked by a high speed shutter in a projector.

As described above, when observing the dark place in the furnace with the camera 5 for monitoring the inside of the furnace, the scanning time controller 7 is set to 1 when the flow velocity of the fine particles is about 1 m / sec.
The scanning time per frame is set to 1/10 seconds. When the flow velocity of the fine particles is about 2 m / sec, it is preferable to adjust so that the scanning time per frame is 1/25 sec. However, it is used as a multiple of 1/30 sec in the capability of ordinary electronic equipment. Since it is preferable, it is set to 1/30 seconds. The scanning time of 1/30 second per frame corresponds to the case where the flow velocity of the fine particles is 1.8 m / second. Therefore, when observing the dark place in the furnace as described above, the dust is first seen, but when the dust concentration is reduced, it becomes equivalent to the case where the flow velocity becomes faster, and the image of the dark place becomes visible.

In the scanning time control device 7, instead of adjusting the scanning time per frame as described above, the frames of the reference scanning time may be added to form the video signal. In this case, for example, a video recorder (not shown) is provided, and the scanning time control device 7 fixes the scanning time of the in-furnace monitoring camera 5 to 1/30 seconds per frame, and the image sensor 9 receives the light. A video signal having two frames of video as one frame is output to the video recorder.

[0044]

As is apparent from the above, according to the monitoring device for the inside of the blast furnace of the present invention, since the image pickup device has sensitivity to the light rays in the visible to near infrared region, it is heated in the blast furnace. The behavior of the gas flow can be grasped by receiving a light beam in the visible to near-infrared region emitted by the present fine particles and obtaining an image of the fine particles.

Further, according to the monitoring apparatus for the inside of the blast furnace of the present invention, the scanning time control means is provided in the image pickup apparatus, and the scanning time of the image pickup apparatus is adjusted according to the situation so that the state of the fine particles can be confirmed. By switching between observation and observation in a dark place in the furnace, even when a large amount of dust is present in the furnace, it is possible to accumulate light in the visible to near-infrared region that slightly transmits the dust in the imaging device. Therefore, it is possible to obtain an image with sufficient brightness to observe the dark place in the furnace.

In the monitoring device for the inside of the blast furnace according to the present invention, the image pickup device is sensitive to a light beam having a wavelength of 0.7 to 1.1 μm, so that the image of the fine particles can be accurately grasped, and When a large amount of dust is present in the furnace, it is possible to facilitate the accumulation of light rays of the wavelength that slightly pass through the dust in the imaging device.

Further, in the monitoring apparatus of the present invention, by providing the light receiving wavelength selecting means in the image pickup apparatus, it is possible to more accurately grasp the image of fine particles under specific conditions.

Further, in the monitoring apparatus of the present invention, by providing an illuminating device for illuminating the inside of the blast furnace, the fine particles and the dark place in the furnace can be easily observed even when the amount of light in the blast furnace is insufficient. . The illumination device can easily observe the fine particles and the dark place in the furnace by providing an illumination wavelength selection unit that selects the wavelength of the light to be illuminated in the range of 0.7 to 1.1 μm.

[Brief description of drawings]

FIG. 1 is an explanatory sectional view of a blast furnace in which a monitoring device of the present invention is installed.

FIG. 2 is an explanatory cross-sectional view of the illumination device of FIG.

FIG. 3 is an explanatory sectional view of a blast furnace in which a conventional monitoring device is installed.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Monitoring device, 5 ... Imaging device, 6 ... Illumination device, 7 ... Scan time control means, 10 ... Receiving wavelength selection means, 17 ... Illumination wavelength selection means.

Claims (5)

[Claims] 1. A monitoring device in a blast furnace having an image pickup device for picking up an image of the inside of the blast furnace, wherein the image pickup device is sensitive to light rays in the visible to near-infrared region. A monitoring device in a blast furnace characterized by comprising scanning time control means for controlling scanning time. 2. The image pickup device has a wavelength of 0.7 to 1.1 μm.
2. The apparatus for monitoring the inside of a blast furnace according to claim 1, wherein the monitoring apparatus has sensitivity to the rays of light. 3. A monitoring device in a blast furnace according to claim 1, wherein said image pickup device is provided with a light receiving wavelength selecting means for selecting a wavelength of a light beam to be received. 4. The monitoring device in a blast furnace according to claim 1, wherein the monitoring device is provided with an illuminating device for illuminating the inside of the blast furnace. 5. The blast furnace furnace according to claim 4, wherein the illuminating device is provided with an illuminating wavelength selecting means for selecting a wavelength of a light ray to be illuminated within a range of 0.7 to 1.1 μm. Monitoring equipment.