KR860000020B1 - Measuring device of velocity and thickness - Google Patents

Abstract

This device measures the velocity and thickness of the charging materials(i.e. iron ore, coke and its mixed layer) in a blast furnace. It transmits the charging value of the inductance(L) of the magnetoscopes(7)(8) through a cable(9) to an electronic measuring apparatus(10). The charging transmitted value of the inductance(L) is converted into current or voltage. The output value is recorded on a recording device(11). "U"-shaped supporters(5) are established respectively along the inner and outer parts of the charging materials in the blast furnace. a nonmagnetic steel pipe(6) is connected perpendicularly to the supporters(5).

Description

Behavior measuring device of blast furnace charge

1 is a schematic view of the blast furnace and measuring apparatus to which the present invention is applied.

2 is a block diagram showing the principle and structure of the detector of the present invention.

3 (a) and 3 (b) are diagrams showing the results measured using the apparatus of the present invention.

4 is a bridge circuit for measuring an output voltage change ΔE depending on the permeability of the charge of the excitation coil 13.

5 is a phase discrimination circuit.

6 is a graph showing an operation waveform of a phase discrimination circuit.

7 is a block diagram showing the electronic measuring device 10 in detail.

8 is a view showing the principle of measuring the thickness and descent speed of the inclusion in the measurement result by the apparatus of the present invention.

9 is a block diagram showing the operation circuit 19 by function.

The present invention relates to a device for measuring the thickness of iron ore (sintered ore), coke and mixed layers, and thus the rate of descent of such charges, which is the charging material of the blast furnace of the present invention.

Since the gas distribution in the furnace is determined according to the distribution state of the charges, and the heat load and furnace sulfur of the equipment are determined, it is important to accurately grasp the distribution state of the charges in order to maintain the proper distribution of the charges. Therefore, various magnetometers (MAGNETIC SENSOR) are embedded in the furnace wall or installed in the vertical tube of the furnace, but the measurement was attempted, but the detection of the mixed layer, the quantitative analysis, and the dynamic drop speed measurement of the charges were not performed.

It was developed to solve this problem of the present invention and the measuring principle is iron ore (sintered ore) is charged to the blast furnace is a ferromagnetic material containing magnetite, coke is a magnetic permeability detection method using a semi-magnetic material, iron ore by a specially designed detector It is an object of the present invention to clearly distinguish between layers and coke layers, to quantitatively interpret the mixed layer and to measure the charge drop rate.

Hereinafter, the present invention will be described in detail through the drawings.

1 shows a schematic diagram of the blast furnace 1 to which the measuring apparatus of the present invention is applied.

In the blast furnace 1, the iron ore 2 and the coke 3 which are charged are charged in layers, and the mixed layer 4 is formed in the interface of these iron ore 2 and the coke 3.

The device of the present invention connected the V-shaped support (5) in the vertical direction between the support (5) between the support (5) to be installed in parallel to the inside and outside of the charge, respectively, each special steel pipe (6) Detectors 7 and 8 are arranged above and below the inside, and these detectors 7 and 8 are electronic measuring devices installed outside the blast furnace with cables 9 disposed inside the support 5 and the special steel pipe 6. (10), the electronic measuring device 10 is connected to the multi-point recording device (11). Cooling gas flows into the support 5 and the special steel pipe 6, and the special steel pipe 6 is upper. By being fixed to the lower support 5, the special steel pipe 6 is prevented from being pushed in the flow direction of the charge. The upper detector 7 is always installed at a position buried in the charge, and two or more detectors may be installed in the special steel sheet 6.

On the other hand, Figure 2 shows the principle and structure of the detector (7) (8), digging a "c" shaped groove in the circumferential direction in the center of the side of the ferrite core 12, wound the excitation coil 13 and the ferrite core (12) The center of the ferrite core 12 is vertically penetrated and fixed and connected to the cable 9 so that the magnetic force lines generated inside the ferrite core 12 form a dense and highly directional magnetic field near the end of the circumference. The circumference of the is thinner than the central portion.

When the alternating current Ei flows through the excitation coil 13, the magnetic flux generated in the excitation coil 13 is connected to the circumferential end of the ferrite core 12 to form a magnetic field in the surrounding space.

When a substance is placed in this magnetic field, the magnetic inductance L of the female coil 13 changes when the intensity of the magnetic field changes and the intensity of the magnetic field changes depending on the magnetic permeability (μ) of the material.

Iron ore (2) charged in the blast furnace (1) is a ferromagnetic material, coke (3) is a weak magnetic material they are charged in a layered. These charges (2) and (3) move from the upper part of the blast furnace (1) to the lower part so as to pass through the magnetic field formed in the horizontal direction of the detector (12) (13) installed inside the vertically fixed nonmagnetic special steel pipe (6). do.

At this time, the inductance (L) of the female coil 13 wound around the ferrite core (12) is

There is a relationship.

here,

K: coefficient

N: number of turns of coil 13

A: cross sectional area of the ferrite core 12 [m ² ]

l: mean (m)

μ: Permeability (μo, μs)

Also, K, A, N, and l are constant, so if you group them together and mark them as K,

L = K (2)

It can be represented as.

This means that the change in the inductance L of the coil 13 means the change in the permeability of the charges 2 and 3.

Therefore, the amount of change in inductance (L) of the excitation coil 13 is transmitted to the electronic measuring device 10 through the cable (9), and then converted into a voltage or a current therein and outputted, and the output is recorded by the multipoint recording device (11). do.

Meanwhile, as described above, the ferrite core 12 has a structure in which the circumferential end portion becomes thinner, and thus the circumferential end portion has a high magnetic flux density and forms a highly directional magnetic field in the horizontal direction around the ferrite core 12. .

In fact, when the height of the circumferential end of the ferrite core 12 is 10 mm, the width of the magnetic field that effectively acts on the contents due to the thickness of the vertical pipe 6 is about 5 mm.

Therefore, only the material placed in the effective device affects the coil 13, so that when the iron ore 2 and the coke 3 are layered, their resolution can be lowered to 5 mm or less.

3 is an example of the results measured using the apparatus of the present invention, in which the left graph in FIG. 3 (a) shows the detection result by the upper detector 7, and the right graph shows the detection result by the lower detector 8. It shows that the descent speed of the charge can be obtained, which will be described below.

Meanwhile, the third (b) drawing shows the iron ore layer 2, the mixed layer 4, and the coke layer 3, and the peak height of the mixed layer is proportional to the degree of mixing, which will be described below.

4 to 9 illustrate the electronic device 10 in detail. In FIG. 4, the output voltage change ΔE depending on the permeability of the charge of the excitation coil 13 has the following expression.

(3)

(3)

ΔE: Output voltage [V] due to change in impedance of coil 13

Ei: Alternating current [A]

X: DUMMY COIL Impedance [Ω]

R: change in resistance component of the coil 13 [Ω]

X: change in impedance of coil 13 [Ω]

에 대해서는 와동상(同相)이 되고, 실수부 변화

에 대해서는 와 90위상이 다르다.Therefore, the output voltage DELTA E changes in the imaginary part

Becomes the vortex phase and changes in the real part

For, the phases of and 90 are different.

에 의한 신호를 취출하기 위해 제5도와 같은 위상 변별회로를 쓰고 있다.The change of the imaginary number above

A phase discriminating circuit as shown in FIG.

The operation waveform of the phase discrimination circuit is shown in FIG.

에 대해서는 DC분이 생기지만 실수부의 변화

에 대해서는 DC분이 생기지 않는다. 따라서 코일(13)의 저항이나 케이블(9)의 저항이 온도 등에 의해 변하더라도 온도에 의한 영향(DRIFT)을 방지하게 되고 유효성부(△X)만 얻게 된다.The output voltage E of the phase discrimination circuit changes in the imaginary part

DC portion is generated but the change of real part

DC does not occur for. Therefore, even if the resistance of the coil 13 or the resistance of the cable 9 changes due to temperature or the like, the influence of temperature DRIFT is prevented and only the effective portion ΔX is obtained.

7 shows a detailed configuration of the electronic measuring device 10 of the present invention and its operation is as follows. Detection coils 7 and 8 and the like for measuring the magnetic permeability of the charge are connected to the bridge circuits 14, respectively.

The bridge circuit 14 receives the alternating current Ei from the oscillator 15 so that the detection coils 7 and 8 convert the impedance changes R and X into voltage signals. Adjust the bridge resistors (R, X ') to be balanced when the coke (3) is placed around. The impedance change voltage E enters the phase discrimination circuit 17 and extracts only the inductance change X of the detection coil as the voltage E by the output of the output device ψ1 synchronized to the oscillator 15. do. (FIGS. 5 and 6) This output E is amplified and smoothed by the amplifier 18 and output in the form of DC voltage Sn to be input to the recording device 11 or enter the arithmetic circuit 19. (Ore layer = Tc, coke = Tc) and the descent rate (V) of the charge is calculated, the specific calculation principle is as follows.

8 is an example of the results measured using the apparatus of the present invention.

Since the upper detector 7 and the lower detector 8 are fixed to the same special steel pipe 6 at a constant distance L, the output SI detected by the upper detector 7 is dependent on the speed change of the charge drop. After another time difference t, it appears as the output S2 of the lower detector 8.

These detector outputs S1 and S2 are input to the calculation circuit 19 to calculate the thicknesses To and Tc of the charge and the drop rate of charge of the charge.

9 shows the operation circuit 19 by function, the operation of which is as follows.

) 또는 하강(

)상태가 판별되어, 상태가 변화는 시점의 펄스(D1, D2, D1, D2')을 만든다. 상부 검출기출력(S1)이 코크스→철광석으로 바뀔때(

)발생하는 상태펄스(D1)는 스케일러 카운터(22)(26)을 개시(START)시키고(23)을 리셋(RESET)시킨다. 그리고 철광석→코크스로 바뀔때( )발생되는 펄스(D2)는 스케일러 카운터(22)을 정지시키고 (26)을 개시시킨다. 그리고 하부 검출기출력(S2)이 코크스→철광석 상태펄스(D1'에 의해 스케일러카운터(26)을 리셋시킨다.Detector outputs S1 and S2 entering the signal discriminator 21 rise (

) Or descent (

The state is determined, and the change in state produces pulses D1, D2, D1, D2 'at the time point. When the upper detector output (S1) changes from coke to iron ore (

The generated state pulse D1 starts the scaler counters 22 and 26 and resets the 23. The pulse D2 generated when switching from iron ore to coke () stops the scaler counter 22 and starts (26). The lower detector output S2 resets the scale counter 26 by coke to iron ore state pulse D1 '.

Through the above process, the thickness of the charges (To, Tc) is measured, the scale counter value (t) of (26) is input to the charge rate calculation circuit 27, the upper and lower detectors (7) (8) Calculate the charge drop rate (V) by dividing the distance (L) by the value (t) of (26).

On the other hand, the inductance change (L) of the coil 13 according to the magnetic permeability (mu) of the charges (2) and (3) is taken out and amplified and measured by DC voltage (S1, S2, etc.). The maximum is 100% for iron ore, and minimum for 100% coke. Therefore, the mixing ratio can be obtained from the measured detector outputs S1, S2 and the like by using the iron ore / coke whose mixing ratio is known in advance, and calculating the phase light coefficients between the detector outputs S1, S2 and the like. .

According to the measuring apparatus of the present invention as described above, since the distribution state of the upper layer of the blast furnace charge can be clearly diagnosed, appropriate measures are possible in the operation of the blast furnace. For example, it is possible to control the amount of follicles and to control the charging, so that stable blast furnace operation is possible. For example, if the thickness of the ore layer is thick on the furnace wall, or if the descent speed is slow, the ore thickness is relatively thick when the next ore is charged, and the coke is relatively thick on the wall. By increasing the air volume toward the furnace wall to promote ore reduction on the furnace wall, the descent speed of the furnace wall is accelerated to adjust the descent behavior of the charge.

Claims (1)

The amount of change in inductance (L) in the magnetic detector (7) (8) according to the state of the charge is transferred to the electronic measuring device (10) by the cable (9), converted into a voltage or a current and output, and the output is a multipoint recording device ( In the apparatus for measuring the behavior of the blast furnace charge by recording 11), a non-magnetic special steel pipe 6 is installed between the support 5 in parallel with the " V " ) Is connected vertically, and a "c" shaped groove is formed in the side surface of the disc ferrite core 12 to wind the excitation coil and the circumferential portion of the ferrite core 12 is thinner than the center portion. Apparatus for measuring the behavior of blast furnace charges, characterized in that two or more fixedly installed in the special oral pipe (6) at regular intervals.

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