JPS6077911A - Method for distinguishing burden in blast furnace - Google Patents

Abstract

PURPOSE:To distinguish the kind of a burden at an arbitrary position in a blast furnace by irradiating electromagnetic waves havning a beam diameter corresponding to the grain size of ore in the furnace from the side of the furnace and by processing the resulting reflection intensity distribution. CONSTITUTION:Electromagnetic waves are emitted from a laser oscillator 10 from two upper and lower positions on the side of a blast furnace at a smaller interval than the thickness of a layer of ore or coke in the furnace. The waves are irradiated on an object 12 in the furnace through a collimator 11 as a electromagnetic waves having a beam diameter corresponding to the grain size of ore in the furnace. The reflection intensity distribution of the magnetic waves reflected from the object 12 is detected with a photodetector 13, and the information is sent to a processing circuit 14. In the circuit 14, the reflection intensity distribution detected with the photodetector 13 is processed to distinguish the kind of the burden.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for determining the type of blast furnace contents.

Conventionally, as a method for determining the type of materials contained in a blast furnace, a magnetic sensor shown in FIG. 1 has been developed.

In Figure 1, the magnetic sensor has core 1 and magnet 2.
, a detection circuit 3, an amplifier circuit 4, and a recorder 5, this magnetic sensor is embedded inside the blast furnace refractory 6. The ore 7 is a ferromagnetic material below the curie point (approximately 850° C.), and the difference in magnetic permeability from the coke 8 is significant. The difference in magnetic permeability between ore 7 and coke 8 is detected by a magnetic sensor to identify the distribution of ore 7 and coke 8.

Figure 2 shows the distribution of coke 8 in the magnetic sensor when ore 7 and coke 8 alternately pass through the part where the magnetic sensor is embedded.
(b) indicates the magnetic flux distribution of the magnetic sensor, and 0 indicates the output of the magnetic sensor. When coke 8 is on the bottom and 617 ore 7 is on the top, when the boundary between coke 8 and ore 7 comes close to the magnetic sensor (a), when the layer of coke 8 comes close to the magnetic sensor (b), when ore 7 is at the bottom and coke 8 is at the top, and when the boundary between ore 7 and coke 8 approaches the magnetic sensor, what is the magnetic flux of each magnetic sensor in (e)? and output distribution.

As shown in (a) and (b) of Figure 2 (b), due to the difference in magnetic permeability between ore 7 and coke 8, when the boundary between ore 7 and coke 8 is close to the magnetic sensor, the magnetic flux 9 is A difference occurs between the upper side and the lower side, and when this difference is detected and output, it becomes a distribution as shown in Figure 2, and the maximum and minimum points of this output distribution are coke 8 - ore 7 and ore 7 - coke 8, respectively. From the output distribution shown in Figure 2 C →, ore 7
and the distribution of coke 8 can be determined.

Furthermore, by separating magnetic sensors for a certain period of time and installing them at two locations, one above the other, it is also possible to detect the unloading speed.

However, when using a magnetic sensor, it depends on the ferromagnetism of the ore, so if the ore loses its magnetism beyond the cue point, the magnetic flux of the magnetic sensor will not change and detection will become impossible. . On the other hand, in a blast furnace, the temperature usually exceeds 850°C many meters below the loading line, so it is impossible to measure the unloading speed at the shaft and lower part of the furnace.

However, when operating a blast furnace, it is strongly desired to detect the layer thickness of ore and coke at any position within the furnace, but when using a magnetic sensor, it is not possible to meet this request for the reasons mentioned above. won.

In order to satisfy the above requirements, the present invention provides a method for identifying charges in a blast furnace that can determine the type of charge at its placement position in the furnace, regardless of changes in the properties of the charge in the furnace. Proposal (B
The purpose is to

The present invention's method for identifying the contents in a blast furnace focuses on the difference in particle size between ore and coke in the furnace, and irradiates electromagnetic waves with a beam diameter corresponding to the particle size of the ore from the side of the blast furnace into the blast furnace. The feature is that ore and coke can be distinguished from the reflection intensity distribution of electromagnetic waves by utilizing the fact that the reflection intensity distribution of electromagnetic waves differs depending on the particle size.

Furthermore, electromagnetic waves with a beam diameter corresponding to the grain size of the ore are irradiated into the blast furnace from the upper and lower sides of the blast furnace side, separated by a distance smaller than the ore and coke layer thickness, into the blast furnace, and the reflection intensity of each of the irradiated electromagnetic waves is measured. Detect the unloading speed of the charge from the distribution, or measure the unloading speed of the charge from each of the above-mentioned reflection intensity distributions. This method is characterized by increasing the thickness of the ore and coke layers from the determination time.

Next, the present invention will be explained based on examples.

FIG. 3 shows the configuration of a sensor used in an embodiment of the present invention.

In the figure, 10 is a laser oscillator that emits laser; 11
16 is a photodetector that detects the reflection intensity distribution of the laser reflected by the object 12; 14 is a reflection detected by the photodetector 16; This is a processing circuit that processes intensity distribution.

Generally, ore undergoes a reduction and powdering phenomenon in a blast furnace, and the average particle size in the shaft portion is approximately several mm. On the other hand, lump coke has an average diameter of about 50 to 60 B at the time of charging, and although it becomes smaller as it descends in the furnace, it is still 60 to 40 B in the lower part of the furnace, and the particle size is larger than the average particle diameter of ore. It is.

Figure 4 (a) shows the scattering state of reflected light when ore 7 is irradiated with a laser beam whose Fi laser beam diameter corresponds to the particle size of ore 7, and (b) shows the scattering state of reflected light when the ore 7 is irradiated with a Fi laser beam whose diameter corresponds to the particle size of ore 7. 8 shows the scattering state of reflected light when irradiated with light.

Since the particle size of the ore 7 is smaller than the particle size of the coke 8, the angle of the reflected light from the ore 7 becomes large.

FIG. 5(a) shows the reflection intensity distribution from the ore 7, and FIG. 5(b) shows the reflection intensity distribution from the coke 8. Since the angle of the reflected light from the ore 7 is large, the reflection intensity distribution from the ore 7 is wider than the reflection intensity distribution from the coke 8.

Therefore, the light intensity at the specular reflection position and the irregular scale Mt1 position is I
plIr and the discrimination function f is f==Ir/Ip (1), ore and coke can be discriminated from the value of this discrimination 1v] number f.

FIG. 6 shows an outline of an embodiment of the present invention.

Insert the Kotoko thread and light receiving system inside the sonde 15, and place the blast furnace surface 1.
Insert the fire into the furnace through the fire 6. A laser beam emitted from a laser oscillator 10 has its diameter adjusted by a collimator 11 and is irradiated onto a charge 12 through an eyepiece 16.

The intensity distribution of the reflected light is measured via a photodetector 16, and a processing circuit 14 subtracts a discrimination function f to discriminate between ore and coke.

Another embodiment of the present invention is shown in FIG.

The sensors 17 and 18 shown in Fig. 6 are installed at the top and bottom of the blast furnace refractory (2): The distance between the sensors 17 and 18 is set to be smaller than the thickness of the ore 7 and coke 80 layers in the furnace. do. An example of the output signals of the sensor 17 and the sensor 18 is shown in FIG. In FIG. 8, the solid line is the sensor 17,
The dotted line indicates the output signal of sensor 1B. Discrimination function f of ore
As is clear from equation (1) and FIG. 5, , is larger than the coke discrimination function fc. The time Δt until the boundary between coke 8 and ore 7 passes sensor 18 after yjV 3t passes sensor 17, unloading speed V is v=L/... (2) Determined by △t.

Also, let the layer thicknesses of ore 7 and coke 8 be Lo + Lc, and the time for the layer of ore 7 to pass through sensor 17 or sensor 18, that is, the layer thickness determination time, To + the layer thickness determination time of coke 8 ΔTc, respectively. Layer thickness Lo.

LC is It can be measured with

Although a laser was used as a signal source in the above embodiment, it is also possible to use microwaves or ultrasonic waves based on the principle of this discrimination method.

As is clear from the above explanation, the present invention distinguishes between ore and coke grains by 1 (the difference between the two), but since this grain size is sufficiently large before the ore melts, it is even larger than L6 until the ore melts. The distribution of the charge can be detected at any point in the upper blast furnace, which has a great effect on blast furnace operation.

[Brief explanation of drawings]

The 11th part 1 is 41 when using a conventional magnetic sensor.
Figure 2 is the output distribution diagram of the magnetic sensor, (a) Il-1' ore-coke distribution diagram, (b)
Figure 4 shows the magnetic flux distribution diagram of the magnetic sensor, (I → output distribution diagram of the magnetic sensor, rj'+ Figure 3 & l, the configuration diagram of the sensor used in the embodiment of the present invention, and Figure 4 shows the reflected light of the laser beam. (a) Scattering state diagram when reflected by kJ ore, (b) Scattering state diagram when reflected by u coke, Figure 5 (a) is reflection intensity distribution diagram of ore, (b )i-L
A reflection intensity distribution diagram of coke, FIG. 6 is a configuration diagram of an embodiment of the present invention, FIG. 7 is a configuration diagram of another embodiment of the invention, and FIG. 8 is an output 11 of the embodiment shown in FIG. 7. It is a diagram showing the moon. DESCRIPTION OF SYMBOLS 1...Core, 2...Magnet, 6...Detection circuit, 4...Amplification circuit, 5...Note 4116...Sieve furnace marine fireworks, 7...Ore, 8... ...Coke, 9...?
u-CTtj-+ 10...Laser oscillator, 11...
・Collimator, 12...Object, 16...Photodetector, 14...DALJ4jj timesr; 1.15...Sonde, 1600. Eyepiece Rares, 17. IO...Sensor. Agent 5P buried soil Ki Toshizo II! I! Figure 2 Figure 3 1st (0) Figure 4 (b) Goods 5 Cause (al (b1

Claims (1)

[Claims] 1. A blast furnace characterized by irradiating electromagnetic waves with a beam diameter corresponding to the grain size of ore from the side of the blast furnace, and identifying ore and coke from the reflection intensity distribution of the irradiated electromagnetic waves. Method for determining furnace contents. 2. Electromagnetic waves with a beam diameter corresponding to the grain size of the ore are irradiated into the blast furnace from two locations above and below the side of the blast furnace, separated by a distance smaller than the thickness of the ore and coke layer in the furnace, and each of the irradiated electromagnetic waves is reflected. A method for identifying charges in a blast furnace characterized by detecting the unloading speed of the charges from the intensity distribution. 6. Electromagnetic waves with a beam diameter corresponding to the grain size of the ore are irradiated into the blast furnace from two locations above and below the side of the blast furnace, separated by a distance smaller than the thickness of the ore and coke layer in the furnace. A method for determining the contents in a blast furnace, which is characterized by calculating the layer thickness of ore and coke based on the unloading speed of the charge and the time required for each of ore and coke from the reflection intensity distribution.