JPS6039123B2 - Blast furnace top charge profile measurement method and device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention reduces the negative effects caused by the light emitted from the light emitter being reflected and scattered by a large amount of fine dust existing in the blast furnace top space, and enables accurate blast furnace top mounting. The present invention relates to a measuring method and device for obtaining a profile of a container.

In a rigid furnace, especially a blast furnace, various raw materials such as iron ore, leech condensation, pellets, coke, etc. charged at the top of the furnace are charged in an ideal distribution in order to achieve high efficiency and long-life operation of the blast furnace. It is necessary to spray the

Therefore, in order to know the distribution state of various raw materials, it is necessary to measure the profile of the top charge, and conventional methods include mechanical, electromagnetic wave, and optical methods. In the mechanical device, a sonde is inserted into the top space of the blast furnace, a weight is lowered from the sonde, the surface position of the blast furnace diamond is detected at several points, and the measurement points are interpolated with straight lines or curved lines to create a profile. However, with this device, since the insertion direction of the i sonde is fixed, it is impossible to measure over the entire top of the furnace.

ii It takes more than 1 minute to insert and withdraw the sonde, so one measurement takes time.

iii Measurement efficiency is poor because measurement cannot be performed while raw materials are being charged.

iv The large size and weight of the device requires special consideration for the mounting frame.

There were other problems.

In addition, electromagnetic wave devices transmit frequency-modulated microwaves from the top of the furnace to the surface of the charge at the top of the blast furnace, and determine the distance based on the difference in frequency with the received reflected wave. The profile is obtained by moving, rotating, or moving the antenna. The beam width of the wave cannot be narrowed, and the measurement accuracy of the uneven surface of the charge at the top of the blast furnace is low.

It is conceivable to focus the beam using an ij array antenna, but at this stage the equipment would be too expensive to be practical.

There were other problems.

Furthermore, as optical devices, there are devices in which a light beam (Koto) is struck on the surface of the top charge of the blast furnace, and the position where the light hits is captured with a television camera, etc.; There is a device that captures the thermal infrared rays emitted from the surface to create a thermal image, and then finds a profile by finding points of equal temperature on the same scanning line from two points on the top of the furnace. , i The accuracy is poor because the image is blurred due to the effects of gas flow, dust, etc. at the top of the blast furnace.

ii Blast Furnace Item When the temperature of the charge rises after charging and begins to emit light by itself, the light beams become difficult to distinguish.

In the latter case, although it is practical,
There was a problem in that measurements could not be made in a state where no temperature gradient was generated on the surface of the blast furnace charge immediately after the raw material was placed in bags.

The present invention was made for the purpose of eliminating the above-mentioned drawbacks of the conventional means. By passing the light reflected from the surface of the object through a polarizing filter that has a polarization characteristic perpendicular to the polarization axis of the forward light transmitter, the influence of scattered light caused by the large amount of dust present in the top space of the blast furnace can be reduced. N ratio (ratio between signal component and noise component)
The method is characterized in that the profile of the charge at the top of the blast furnace is measured by scanning the surface of the charge at the top of the blast furnace with the light beam.

The present invention will be explained below with reference to the drawings.

First, the principle of the present invention will be explained with reference to FIGS. 1 to 4.

For example, fine dust of 15 to 50 particles per particle is always present at the top of the blast furnace, and Koto is scattered and absorbed by the dust.

That is, as shown in FIG. 1, when light is emitted from the light emitter 1 of the light transmitter 4, which is composed of a light emitter 1, a beam shaping lens 2, and a polarizer 3, the light is transmitted through the Koto molding lens 2 to the Koto 5'. The light is deflected by the polarizer 3 and emitted into the space 6. At this time, the light beam 5' is not polarized, so it is a light wave with the same intensity in all directions, and it exits the polarizer 3, as shown in Figure 2 (A) in the calendar (A) of Figure 1. The later Koto 5 is, for example, as shown in Figure 1, Figure 1, Figure 2, Figure 2, Figure 2.
It is light that is polarized so that it has intensity only in the vertical direction. The aforementioned polarized light beam 5 travels through a space 6 containing fine dust 7 while colliding with the dust 7, and is diffusely reflected by the rough surface 9 of the blast furnace top charge 8.

A part of the Koto 5 that collides with the dust 7 is scattered and absorbed over the entire area that the Koto passes through, but the scattered light is backscattered as shown in Figure 2 C, and as shown in Figure 2 2. Lateral scattering occurs as shown in FIG. 2, and forward scattering occurs as shown in FIG. These scattered lights have the property of retaining the polarization characteristics of the light east 5 to a considerable extent. The degree of retention of the polarization characteristics described above varies depending on the wavelength of the light and the particle size of the dust 7, but in a state where particles ranging in size from one Buddha to several hundred mountains and rivers are distributed, such as at the top of a blast furnace, the polarization characteristics are maintained. Using the red light of a helium neon laser as an example, the light intensity is expressed by the relative value of the light intensity divided into eight equal angles for convenience, as shown in Figures 3 and 4. It can be seen that the conservation of polarization is strong on the plane formed by the central axis of the light beam 5 and the polarization axis, and on a plane that includes the central axis of the light beam 5 and intersects with this plane, and is weak in oblique directions.

On the other hand, if we look at the light diffusely reflected by the target surface 9 of the blast furnace top charge 8 in the positions T and H in Figure 1, it retains the polarization characteristics of Koto 5 to some extent, but the retention is weak. , it has a considerable intensity in the direction perpendicular to the polarization axis of Koto 5.

This mirror direction includes the plane formed by the central axis of the light east 5 and its polarization axis, and the center axis of the light east 5, and is the same on a plane that intersects this plane at right angles, although there are differences in degree. The present invention utilizes the polarization characteristics of the scattered light and reflected light described above.

That is, the reflected light from the rough surface 9 of the top charge obtained as described above is reflected on the plane formed by the central axis of the light east 5 and its polarization axis, or on the plane including the center axis of the light east, and on this plane. When the light is received by the receiver through a filter having polarization characteristics in the direction perpendicular to the polarization axis of the light beam 5 from a plane that intersects at right angles, the influence of scattering on the light path is reduced, and It becomes possible to capture reflected light from a light spot with a good S/N ratio. Here S is the useful signal component and N is the noise component. The present invention applies the above-mentioned principle, and embodiments of the present invention utilizing such principle will be described below with reference to FIGS. 5 to 115. In Fig. 5, 11 is the top of the blast furnace, 12 is the surface of the blast furnace top 13, 14 is a light transmitter installed at a required position on the top of the blast furnace 11, and 15 is the top of the blast furnace, similar to the light transmitter 14. 11 Light receivers placed at required positions,
16 is the light emitted from the light transmitter 14 to the surface 12 of the blast furnace top charge 13; 17 is the surface 12 of the blast furnace top bag charge 13;
Of the light beams 16 that are diffusely reflected by the light beams, the light beams that enter the light receiver 15 are shown.

The internal structure of the light transmitter 14 is shown in FIG. 6, and is composed of a light emitter 18, a Koto molding lens 19, and a polarizer 201, similar to the light transmitter in FIG. 1 whose principle was explained. The light beam 16 emitted from the light transmitter 14 has a surface 12 of the blast furnace top charge 13 with a diameter of 10 to 15 mm so that an average reflected light can always be obtained in consideration of the grain size of the blast furnace top charge 13. The beam is set to have an angular width so as to illuminate the approximately circular shape of the skin, or to form a parallel beam of light, and is modulated at a frequency convenient for modulation and demodulation.
The light is horizontally polarized by a polarizer 20 in one direction (in this example, the vertical direction as explained in the explanation of the principle).

In addition, the light transmitter 14 can be connected to the blast furnace top 11 from the mounting window or other parts.
It is configured to be sealed or purged with an inert gas such as N2 gas to prevent dust from entering (not shown). The internal structure of the light receiver 15 is also shown in FIG.
A condensing lens 21 with a depth of focus capable of covering the entire distance, and a polarizing filter 2 having a polarization axis perpendicular to the polarization axis of the polarizer 20 of the light transmitter 14 (in the horizontal direction in this example).
2. It is composed of two or more light receiving sensors (for example, an array type photo sensor) 23, etc., for determining the difference in intensity depending on the direction of the received light.

The light transmitter 14 includes a modulator 24 that modulates the light emitter 18.
The light receiver 15 is provided with a narrow band pass filter 25 that passes only signals at the modulation frequency of the light emitter 18 and frequencies in the vicinity thereof.

The light transmitter 14 is also provided with a drive device 26 that rotates and moves the light transmitter 14. By moving the mirror, the light spot is shifted and the light spot can move on the same scanning line as the light receiver 15.

Further, the light receiver 15 is provided with a drive device 27 that rotates and swings the light receiver 15, and the spot on the surface 12 of the blast furnace top charge 13 irradiated by the light beam of the light transmitter 14 is It is configured so that it can be tracked within the detection range of the light receiving sensor 23. Modulator 24 and drive device 26 on the light transmitter 14 side
An arithmetic and control device 28 such as a computer is electrically connected to the arithmetic and control device 28 , and a bandpass filter 25 and a drive filter 26 on the side of the light receiver 15 are electrically connected to the arithmetic and control device 28 . is electrically connected to a display device 29 such as a cathode ray tube.

Therefore, the driving devices 26 and 27 are driven to drive the light transmitter 14 and the light receiver 15, and the surface 12 of the blast furnace top charge 13 is
is scanned, and the profile of the blast furnace top charge 13, its temporal change, the thickness of the charge, the descending speed of the bagged material, etc. can be displayed on the display device 29 from each angle data. ing. The forward light transmitter 14 and the light receiver 15 may be arranged symmetrically with respect to the blast furnace center line as shown in Fig. 5, or they do not need to be symmetrical; It may be arranged on one side of the furnace section 11.

Note that 30 in the figure is an imaginary line connecting the center of the light transmitter 14 and the light receiver 15, that is, the light emitting point and focal point. Next, in order to simplify the explanation, the operation of the present invention will be described below for a case where the light transmitter 14 and the light receiver 15 are arranged symmetrically with respect to the center line 1 of the top of the blast furnace.

When measuring the profile, first, the sea bream lines of the light transmitter 14 and the light receiver 15 (the rut line of Koto 16 and the mari line of Koto 17) are on a vertical plane passing through the blast furnace top center line 1, and the blast furnace It is adjusted so that it can intersect with the surface 12 of the top charge 13, and then the drive device 26 is driven, and the light transmitter 14
It irradiates the position that is assumed to be the boundary line between the blast furnace top 11 and the blast furnace top charge 13, which is closer to the top 11, and sends a mirror tilt angle signal in the direction of the light east rut to the arithmetic and control unit 28. The device 27 is driven, and the light receiver 15 receives the reflected light from the irradiation position (light spot) near the boundary line between the blast furnace top 11 and the blast furnace top charge 13, which is closer to the forward light transmitter 14. Adjustment is made so that the light can be received, and a tilt angle signal in the direction of the center of the light spot is sent to the arithmetic and control unit 28, and the light transmitter 14
The driving device 26 moves the spot of light irradiated onto the surface 12 of the top charge 13 of the blast furnace stepwise by a small distance and receives the light with the light receiver 15.
.
Then, the motion angle of the optical axis of the light receiver 15 is measured.

When scanning a certain point on the same scanning line, when light is emitted from the light emitter 18 of the light transmitter 14, as explained in the explanation of the principle in FIG.
The light is shaped by a Koto molding lens, polarized by a polarizer 20, and emitted into the blast furnace top li.
The dust travels inside the blast furnace top 11, collides with the dust floating in the space of the top 11, and a part of it is scattered and absorbed, collides with the surface 12 of the blast furnace top bag 13, and is reflected. However, a part of it is received by the light receiver 15 as scattered light 7, but most of the scattered light in the light path is removed by the polarizing filter 22, and is received by the light receiving sensor 23.
The photoelectrically converted signal is photoelectrically converted by the light receiving sensor 23, and the photoelectrically converted signal is sent to the bandpass filter 25,
By the band pass filter 25, the blast furnace top charge 1
3 itself is removed, and only signals at the modulation frequency of the light emitter 18 and frequencies in the vicinity thereof pass through the band pass filter 25, and the signals passing through the band pass filter 25 and the driving device 26, The forehead inclination angle signals of the light transmitter 14 and the light receiver 15 sent from the light transmitter 14 and the light receiver 15 are sent to the arithmetic and control unit 28. Since the center positions of the light transmitter 14 and the light receiver 15 are known, the light transmitter 14 and the light receiver 15 are From the oblique angle signal of the optical axis of the light receiver 15, the position of the above point is calculated by simple trigonometry.

If there are two light receiving sensors 23, the light spot can be determined by moving the optical axis of the light receiving device 15 on the same scanning line as the optical axis of the light transmitter 14 and finding the direction in which the two sensor outputs are equal. We will be looking for the direction of
If a multi-element light-receiving sensor such as a photo array is used, the direction of the light spot can be determined from the difference in the light incident on each element, thereby simplifying the follow-up operation of the driving device 27.

However, a bandpass filter must be provided for each light receiving element. When the measurement of one point on one scanning line is completed, next, the light transmitter 14 is set at a very small angle (for example, one angle that can cover the diameter of the top of the blast furnace in 100 steps).
angle corresponding to the step)
5 side, and the light receiving sensor 23 of the light receiver 15
The direction of the light spot is detected, and the position is calculated by the arithmetic and control unit 28.

If the light receiving sensor 23 is an array type sensor having a sufficient viewing angle with respect to the scanning direction, the driving device 27 of the light receiving device 15 does not need to be constantly driven in response to the movement of the light transmitter 14, and the light receiving sensor 23 It is sufficient to drive the light receiver 15 from time to time so that the light spot does not deviate from the light spot. In this way, the position of the second light spot is determined. In this way, if scanning the surface 12 of the blast furnace top charge 13 using polarized light is performed on the same scanning line for the entire fleas in the blast furnace section, one scanning line passing through the blast furnace top center line 1 can be obtained. You can get a minute profile.

The state of the sensor output when the light receiving sensor 23 is a multi-element optical sensor is shown as an output curve X in FIG. 7, and an output curve Y in FIG. 7 is an output curve when polarized light is not used. . The force curve Y has a poor S/N ratio and therefore has a large output, but the curve is smooth and it is difficult to find the peak corresponding to the direction of the light spot, whereas the output curve X has a good S/N ratio and therefore has a large output. Although the output is small, it is easy to find the peak part.

Note that the axis indicates the arrangement order of the multi-element sensors.
Next, a method for obtaining profiles on other scanning lines will be explained.

The scanning line that passes through the blast furnace top center line 1 was used to fix the rotation angle of the drive devices 26 and 27 to zero and only perform head movement, but the light was sent on another scanning line that did not pass through the blast furnace top center line. When scanning with the transmitter 14 and the receiver 15, the transmitter 14 and the receiver 15 are rotated in the same direction by the same minute angle about the virtual line 30, and the same movement operation as described above is performed at the same rotation angle. to obtain the profile for one scanning line.

This means that an imaginary line plane that revolves around the imaginary line 30 traces a curved line that intersects with the blast furnace top charge 13. If such an operation is performed one after another over the entire surface 12 of the blast furnace top charge 13 for each step of the rotation, the profile of the entire blast furnace top charge can be determined.

Furthermore, by performing the above operations at regular time intervals, it is possible to determine the temporal change in the profile of the blast furnace top charge, and calculate the descending rate (unloading speed) of the blast furnace top charge. Furthermore, if this operation is continued before and after charging the raw material, it is possible to calculate the charging thickness of the top charge of the blast furnace by taking into account the unloading speed. device 29
By displaying these various data on the top of the vehicle, it can be used as a guideline for driving.Next, a profile display method will be explained.

The measurement results on the i scanning lines are displayed as instantaneous values of the profile at the measurement time, as shown in FIG. ii If similar operations are performed at regular time intervals (for example, 1 sand), changes in the profile over time will be displayed as shown in FIG.

iii By dividing the change in profile in a certain time interval by the time difference, the average value of the unloading speed of each layer can be displayed as shown in FIG. 10.

iv By calculating the time course including going back in time using the average value of the unloading speed, as shown in Figure 11, the profile immediately after raw material charging and the previous profile at that point in time can be obtained. The profile of the charge can be estimated. v From the difference in height between the two profiles, the thickness distribution of the blast furnace top charge can be displayed as shown in FIG.

Furthermore, if the bagging pattern by the raw material bagging device is continuously the same, the average thickness of the top charge of the bran furnace over the past N times can be displayed as shown in Fig. Thickness distribution can be grasped with less error. Although it is difficult to display the above information for the entire blast furnace top charge on one screen, it is possible to display it for any longitudinal section according to the operator's command, and for one profile, It can also be displayed using bird track charts A and B in FIGS. 14 and 15.

In addition, in the examples of the present invention, the case where the profile measurement of the blast furnace charge is carried out has been explained. It can be used, and the profile measurement is not performed on the entire surface of the bag.
Make the measurement surface smaller or scan line 1
It is possible to measure the profile of a book only, as long as it is traced on the same scanning line.
The transmitter and receiver can be arranged asymmetrically rather than symmetrically with respect to the center line of the top of the blast furnace, or even if the transmitter and receiver are not arranged on the plane that includes the center line of the top of the blast furnace. Good thing,
It is also possible to modulate the light transmitter by a mechanical method after it becomes light in the light emitter, and the light emitter is a monochromatic light such as a laser, and the light receiver side is equipped with a light bandpass filter that blocks other than this monochromatic light. It is possible to add a means to reduce the effect of light emission from the top charge itself by attaching the , and that various other changes can be made without departing from the gist of the present invention. Of course.

Since the rotating blast furnace charge profile measuring method and apparatus of the present invention has the above-described configuration, it can achieve various excellent effects as described below.

1. The profile of the top bag can be measured with high precision over the entire top of the blast furnace.

0 Measurement is optical and electronic, and measurement time can be shortened compared to mechanical methods.

(m) The level and unloading speed of blast furnace top charges can also be detected, making it useful for monitoring blast furnace conditions and abnormalities.

W Since the charging thickness distribution of the blast furnace top charge for each charge is known, ideal material charging is possible by adjusting the operation of the material charging device, contributing to high efficiency and long life operation of the blast furnace. can.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is an explanatory diagram of the principle of the method and apparatus for measuring the profile of blast furnace top charge according to the present invention, Fig. 2 is an explanatory diagram showing the state of polarized light in Koto, and Fig. 3 is an explanatory diagram of the conservation of polarization when Figure 1 is viewed from the mm direction, Figure 4 is an explanatory diagram of the conservation of polarization when Figure 1 is viewed from the W-N direction, and Figure 5 is an explanatory diagram of the conservation of polarization when Figure 1 is viewed from the W-N direction. 6 is an explanatory diagram of the vicinity of the blast furnace head section of the blast furnace top charge profile measuring method and apparatus of the present invention, and FIG. 6 is a detailed explanatory diagram of the blast furnace top charge profile measuring method and apparatus of the present invention, FIG. 7 is a graph showing the relationship between the arrangement order of the multi-element photosensor and the output of the sensor when the light-receiving sensor in the device shown in FIG. 6 is a multi-element photosensor. 9 is a graph showing the relationship between the radial position of the blast furnace top and the height of the blast furnace top bag obtained by the apparatus shown in FIG. , Figure 10 is a graph showing the average value of the unloading speed of each part of the blast furnace top charge, and Figure 11 is a graph showing the average value of the unloading speed of each part of the blast furnace top charge immediately after bagging. A graph showing the estimated profile of the current and previous blast furnace top charges, Figure 12 is a graph showing the thickness distribution of the blast furnace top charges, and Figure 13 is the same past N
Graph showing the average thickness of the blast furnace top charge in batches, 1st
Figures 4 and 15 are views of the top charge of the same blast furnace.

. It is an explanatory diagram when a file is displayed on a display device as a bird track map. In the figure, 11 is the blast furnace element, 13 is the blast furnace top bag, 14 is the light transmitter, 15 is the light receiver, 18 is the light emitter, 19
is Koto molded lens, Futagawa polarizer, 21 is condensing lens,
22 is a polarizing filter, 23 is a light receiving sensor, 24 is a modulator, 25 is a bandpass filter, 26 and 27 are driving devices, 28 is an arithmetic control device, and 29 is a display device.

Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 1 Figure 12 Figure 13 Figure 14 Figure 15

Claims (1)

[Scope of Claims] 1. The surface of the blast furnace top charge is irradiated in a spot shape with the speed of light polarized by a light transmitter, and the light reflected from the surface of the blast furnace top charge is transmitted to the light transmitter. By passing the light through a polarizing filter with polarization characteristics perpendicular to the polarization axis, the influence of scattered light due to the large amount of dust present in the top space of the blast furnace is reduced, and the S/N ratio (ratio of signal component to noise component) is improved. A blast furnace top charge profile characterized in that the profile of the blast furnace top charge is measured by receiving light as a good optical signal and scanning the surface of the blast furnace top charge with the light beam. Measuring method. 2. A light transmitter equipped with a light emitter and a polarizer that polarizes a light beam, and a light receiver equipped with a polarizing filter and a light receiving element having polarization characteristics perpendicular to the polarization characteristics of the polarizer provided in the light transmitter, It is arranged at a desired position on the top of the blast furnace so as to be freely tiltable and freely turnable in a direction perpendicular to the tilting direction, and a modulator is provided on the light emitter of the light transmitter, and a bandpass filter is provided on the light receiving sensor output side of the light receiver. A driving device for tilting and turning the light transmitter, a driving device for tilting and turning the modulator and the light receiver, and the bandpass filter are respectively connected to an arithmetic and control device, and the A blast furnace top charge profile measuring device, characterized in that a display device is connected to a control device.