JPH0826376B2 - Blast furnace core measuring method and device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention provides physical properties such as temperature and air permeability of a furnace core formed mainly in a coke particle deposit formed in a hearth of a blast furnace. The present invention relates to an indirect measurement method and device.

[Prior Art] How to control and stabilize the blast furnace operation is an important issue in the steelmaking industry, and various detecting ends are provided in the blast furnace body. However, despite the importance of the detection end of the furnace core, which is mainly formed by the deposition of coke particles above the pool and below the cohesive zone in the hearth of the blast furnace, it is as widely used as a shaft sonde. The current situation is that it has not been done.

For example, as proposed in JP-A-61-257405 and JP-A-63-210208, a probe with a cooling mechanism, which incorporates a glass fiber connected to image processing from the tuyere of the blast furnace, is installed in the furnace core. There is a direct measurement method such as a method of directly inserting the temperature into the furnace and measuring the temperature, or a method of detecting resistance to inserting the sonde into the furnace core. Further, as proposed in Japanese Patent Laid-Open No. 55-104412, a method of arranging a radiation scanner and a detection group on the outer periphery of the blast furnace to continuously monitor the inside of the furnace and an indirect measurement method are known. .

[Problems to be Solved by the Invention] The core lead sonde related to the conventional direct measurement method is
Since it is a method of inserting the sonde directly into the furnace core by passing through the raceway which is the high temperature part in the furnace, equipment, equipment, especially,
Since the sealing mechanism becomes large and the measurement work itself is dangerous, it is impossible to measure easily from arbitrary tuyeres arranged in the circumferential direction of the furnace.

Further, the radiation scanning method related to the indirect measurement method requires equipment to shield the radiation around the casting floor.

The state of the blast furnace varies from moment to moment, and it is desired to detect the furnace core in real time and at the same time to detect the circumferential balance.

In view of such problems, the present invention does not directly insert a detection end such as a sonde into the core, and without giving disturbance to the blast furnace periphery, indirectly or indirectly with respect to the physical characteristics of the entire core. The present invention provides a measuring method and device.

[Means for Solving the Problems] The first aspect of the present invention is: (1) Physical characteristics such as temperature and air permeability of a furnace core formed mainly by depositing coke particles in a hearth of a blast furnace. In measuring, the shock wave generated outside the furnace through the waveguide inserted into the tuyere arranged in the hearth is guided from the furnace wall to the inside of the furnace, and the shock wave emission time is measured, The characteristic is that the shock wave propagating through the furnace core is received by a plurality of receiving sensors provided on the hearth hearth wall, and the physical characteristics of the furnace core are calculated and estimated from the attenuation rate and propagation velocity of these shock waves. A method for measuring a blast furnace core part, the second invention is (2) wherein the shock wave transmission / reception operation is performed by circulating a plurality of tuyere parts in the furnace circumferential direction. The measurement method of the blast furnace core part of the third invention is (3) the impact generated by instantaneous explosive combustion. A shock wave is used to measure the blast furnace core part according to the above (1) or (2), and a fourth invention is (4) a shock wave generator provided outside the furnace, and the generator. One end is connected to, the other end is directed into the furnace, a waveguide for supplying the generated shock wave into the furnace from the tuyere, a plurality of receiving sensors provided on the hearth furnace wall, from each receiving sensor The measuring device for the blast furnace core, which comprises a recorder for recording the reception waveform of each of the shock waves and the time at which each shock wave is emitted, and a calculation display for calculating and displaying the physical characteristics of the core from the reception waveform, The present invention is (5) the apparatus for measuring a blast furnace core as set forth in (4), characterized in that a plurality of waveguides having different lengths are connected to one shock wave generator.

[Operation and Example] Hereinafter, a specific description will be given with reference to the drawings showing an example apparatus of the present invention.

Various vibrations are generated and propagated in the blast furnace during operation, and the attenuation is too large with ordinary ultrasonic waves to propagate inside the hearth diameter of more than 10 m, and it cannot be measured well. Therefore, the present invention focused on shock waves as a result of experiments.

The shock wave in the present invention is generally called a strong compression wave propagating in a shrinking medium, and specifically, for example, instantaneous combustion of gaseous fuel or instantaneous combustion of explosive powder or the like. The shock wave generated by using can be adopted.

As shown in FIGS. 1 and 2, the shock wave is generated in the blast furnace 3
It is generated by the shock wave generator 1 provided outside the furnace. The shock wave generator 1 can generate shock waves intermittently at specific intervals. This shock wave is directed to the hearth of the blast furnace 3 through the waveguide 2 connected to the generator 1 and to the core of the blast furnace 3, which is mainly formed of a deposit of coke particles, and is supplied from the furnace wall 4 into the furnace. . As a connection mode between the shock wave generator 1 and the waveguide 2, as shown in FIG.
There is a method of connecting one of the above shock wave generators 1 or a method of connecting a plurality of, for example, four waveguides 2 to a pulse generator 12 for intermittently generating shock waves as shown in FIG. . With the latter method of connecting a plurality of waveguides 2, it is possible to provide a difference in the length of each waveguide 2, and it is possible to delay the supply timing of the shock wave into the furnace. The tip of the waveguide 2 is provided on the furnace wall 4 so as to face the furnace core as described above. As a characteristic installation mode of the waveguide 2, for example, a part of the pulverized coal blowing burner 6 installed in the tuyere 5 can be diverted. When supplying the shock wave generated by this method into the furnace, the pulverized coal blowing is interrupted and the shutoff valve 7 in the pulverized coal flow path is stopped.
By closing, the shock wave is promoted to propagate to the front of the tuyere 5. In the case of the tuyere 5 in which no diverting means such as a burner for blowing pulverized coal is installed, the dedicated shock wave waveguide 2 is arranged in the same manner as the burner for blowing pulverized coal.

The number of the waveguides 2 installed is at least three at equal intervals in the circumferential direction of the furnace, or four cross-shaped positions a, b, c, in the circumferential direction of the furnace.
It should be installed in each d. When the number of the installed waveguides 2 increases, the measurement accuracy described later increases.

A plurality of receiving sensors 8 are arranged in the furnace circumferential direction on the furnace wall 4 at a level substantially equal to the level at which the waveguide 2 is installed.
The reception sensor 8 is composed of means for detecting sound waves, and for example, a pressure sensitive element can be used. Various modes can be applied to the installation position of the reception sensor 8. For example, when the reception sensor 8 is installed inside the furnace of the hearth furnace wall 4, a plurality of them are arranged at equal intervals in the furnace circumferential direction in consideration of heat resistance. It is possible to adopt a system in which the tuyere 5 is installed at the tip of the water-cooling jacket portion, or a system in which a water-cooled probe (not shown) incorporating the receiving sensor 8 is installed in the tuyere 5 or the furnace wall 4. When the receiving sensor 8 is installed outside the hearth hearth wall 4, the method of exposing the receiving sensor 8 to the blow pipe part located at the rear end of the tuyere 5 or the peep window part at the rear end is adopted. In this case, the tuyere 5 or the blow pipe functions as a receiving waveguide.

The number of receiving sensors 8 to be installed is acceptable as the measurement accuracy as long as at least eight receiving sensors 8 are installed on the furnace wall portion facing the waveguide 2.

The shock wave generated by the shock wave generator 1 is applied to the waveguide 2
When it is supplied from the furnace wall to the inside of the furnace via, the receiving sensor 8 closest to the waveguide 2 that has emitted the shock wave receives the shock wave at the same time as the emission, and another receiving sensor 8 arranged in the furnace circumferential direction. Receives a shock wave after a delay time corresponding to that part. As shown in FIG. 2, the waveguide 2 and the receiving sensor 8 provided in each tuyere 5 are used, and after the maximum delay time from the shock wave emission to the transmission, the waveguide 2 in another part is used. By repeating the operation of supplying and receiving the shock wave into the furnace, the shock wave directionally emitted from the specific waveguide 2 has a relatively weak ripple effect (shock wave emission waveguide Since both side regions of the core are complemented by the next operation, it is possible to measure a plurality of points in the circumferential direction of the furnace core.

The shock wave received by the above operation is amplified by the amplifier 9 and recorded as a received waveform in the recorder 10, and the operation display 11 performs an operation in accordance with the desired physical characteristics to be described later.
Is applied to

Each received wave applied to the arithmetic display unit 11 is subjected to data processing by the CT scanning method. Specifically, there are a summation method, a convolution method, a least square method, and the like, but the least square method is suitable because the number of data obtained in the circumferential direction is not so large.

For example, when obtaining the temperature distribution as the physical characteristics of the furnace core, the sound velocity v in the gas is generally given by the following equation.

Here, κ is the specific heat ratio, R is the gas constant, and T is the gas temperature. If the propagation distance is known, the gas temperature can be known from the propagation time.

For each projection data in CT, the transmission point A to the reception point B is divided into sections n, and assuming that the propagation velocity is constant within that section, the propagation time τ _AB from transmission to reception is expressed by the following equation. It

Here, l _i : propagation distance of section i, T _i : temperature of section i, v
(T _i ): Propagation velocity u _{i of} section i: Gas velocity of section i.

On the contrary, assuming that the propagation time from the transmission point B to the reception point A is Z _BA and the tuyere tip is aside, u _i at the core of the blast furnace is sufficiently smaller than v _i (2 From the expression) It is represented by.

From equation (3), the equation expressing the temperature distribution of the furnace core is the following multidimensional simultaneous equation.

Is the measured transit time, Is the distance in section i, Is the reciprocal of V _i in section i and has a relationship with temperature T _{i according} to equation (1).

If there are n or more data items, based on equation (5), the least squares method Is minimized And the temperature distribution T _i can be obtained from this.

As mentioned above, various noises are generated in the blast furnace, and the nozzles are mixed in the received waveform.However, since the cycle of temperature change of the furnace core is long, the above measurement operation is repeated periodically to obtain The S / N ratio can be increased by adding the received waveforms. A shock wave is preferably generated by the pulse generator 12 periodically and in sequence.

Although the description has been made based on the case of calculating the temperature as the physical characteristic, it goes without saying that the theoretical formula corresponding to the characteristic value is developed when other physical characteristics such as the shock wave attenuation rate corresponding to the air permeability are obtained.

The results of measuring the core temperature distribution of the experimental blast furnace using the method of the present invention are shown in FIG. The shock waves generated by the method of instantaneously burning gas fuel are sequentially supplied into the furnace from the tuyere 5 at the four cross-shaped positions in the circumferential direction of the blast furnace at intervals of 3 seconds and received by 15 tuyere 5 10 operations to be received by the sensor 8
Repeated times. It is the result of calculating the received core waveform by calculating the received waveform.

[Advantage of the Invention] According to the present invention, since the physical characteristics such as the temperature distribution of the furnace core can be indirectly measured in a short time during the operation of the blast furnace, the measured physical characteristic information is immediately reflected in the operation, and the result is again measured. Since it can be monitored by measuring, stable operation can be maintained.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional explanatory view of an apparatus example according to the present invention, FIG. 2 is a horizontal cross-sectional explanatory view showing an outline of the present invention, and FIG. 3 is a model diagram showing a temperature distribution of a core portion in an experimental furnace. is there. 1 ... Shock wave generator, 2 ... Waveguide 3 ... Blast furnace, 4 ... furnace wall 5 ... tuyer 6 ... pulverized coal blowing burner 7 ... shut-off valve, 8 ... reception sensor 9 ... amplifier , 10 …… Recorder 11 …… Computation display, 12 …… Pulse generator

Claims (5)

[Claims] 1. A tuyere located in the hearth of a blast furnace when the physical properties such as temperature and air permeability of a core formed mainly of coke particles are measured in the hearth of the blast furnace. The shock wave generated outside the furnace was guided from the furnace wall to the inside of the furnace through the waveguide inserted in the furnace, and the shock wave emission time was measured, and the shock wave propagating through the furnace core was provided on the hearth furnace wall. A method for measuring the core of a blast furnace, which comprises receiving and receiving a plurality of reception sensors and calculating and estimating the physical characteristics of the core from the attenuation rate and propagation velocity of these shock waves. 2. The method for measuring a blast furnace core as claimed in claim 1, wherein the shock wave transmission / reception operation is performed by circulating the tuyere in a plurality of directions in the furnace circumferential direction. 3. The method for measuring the core portion of a blast furnace according to claim 1, wherein a shock wave generated by momentary explosive combustion is used. 4. A shock wave generator provided outside the furnace, a waveguide which connects one end to the generator and directs the other end into the furnace, and supplies the generated shock wave from the tuyere into the furnace, the furnace Consists of a plurality of reception sensors provided on the hearth wall, a recorder for recording the waveforms received from each of the reception sensors and the time at which each shock wave is emitted, and a calculation display for calculating and displaying the physical characteristics of the core from the reception waveforms A measuring device for the core of a blast furnace characterized by the above. 5. The apparatus for measuring the core portion of a blast furnace according to claim 4, wherein a plurality of waveguides having different lengths are connected to said one shock wave generator.