JPS62192511A - Method for estimating falling position of raw material charged into rotary chute type blast furnace - Google Patents

Abstract

PURPOSE:To detect the falling position of a raw material with simple constitution and high accuracy by inserting and disposing a long-sized member into a raw material falling space in the cross direction of a blast furnace and respectively providing oscillation detecting sensors to both ends, on the outside of the furnace, of such long-sized member. CONSTITUTION:The long-sized member 8 is inserted and disposed into the blast furnace so as to penetrate the wall 1 thereof and cross the inside of the furnace. The oscillation detecting sensors 9, 10 are respectively provided to both ends, on the outside of the furnace, of the long-sized member 8. The raw material 4 is charged by a chute 3 into the furnace in the above-mentioned constitution and the acoustic oscillations generated upon collision of the raw material 4 against the point P of the long-sized member 8 are transmitted to the oscillation detecting sensors 9, 10. The difference DELTAT(Ta-Tb) between the time Ta and Tb until the acoustic oscillations are transmitted to the sensors 9, 10 is measured and the distance from the sensor (or 10) up to the collision point P is measured. Plural thermometers A1-A9 are installed in the longitudinal direction of the long-sized member 8 to measure the temps. in the respective parts so that the change of the velocity of sound in the long-sized member 8 at various parts, etc., is subjected to temp. compensation.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for estimating the charging and falling position of blast furnace raw material, and more specifically, the present invention relates to a method for estimating the charging and falling position of blast furnace raw material. This invention relates to a method for estimating the falling position of raw material from a raw material charging chute using a long member provided and vibration detection sensors provided at both ends of the elongated member.

[Conventional technology]

Raw materials for blast furnaces, such as coke and iron ore, are each weighed in packets or the like and transported to the top of each blast furnace, and charged into the blast furnace via a charging device.

Conventionally, the bell method was the mainstream charging method for blast furnace raw materials, but it was difficult to control the position of the newly charged material on top of the previously charged material in the blast furnace. However, as will be described later, this control of the landing position plays an extremely important role in controlling the operation of the blast furnace, and if the control of the landing position is incomplete, there may even be no guarantee that the stable operation of the blast furnace can be ensured. For this reason, a new method (so-called bellless method) that could replace the bell method was investigated, and a rotating chute charging method was developed. In this method, a cylindrical or gutter-shaped chute is arranged downward from the top of the blast furnace, and the lower side of the chute can swing freely in a concentric or spiral manner with the upper side of the chute as a pivot point. It is composed of Therefore, the raw material discharge port at the lower end of the chute can be directed to any desired position inside the blast furnace, and the above-mentioned raw material landing position has come to be controlled to a fairly high degree.

Now, in blast furnace operation, it is necessary to continue smooth and good operation, and to maintain the gas distribution in the furnace shaft (distribution in the rising gas passage) in an appropriate state, the obvious effects of the gas should be maintained. Efficient use of reducing capacity has become an important issue. For these reasons, each of the raw materials is charged after being sized, but the gas distribution is greatly influenced by how the raw materials dropped from the rotating chute are deposited in the blast furnace. I also know that. The formation of a central gas flow is considered to be an important point in recent furnace operation conditions, and to achieve this, the gas resistance on the center side of the shaft must be considerably reduced to direct the gas toward the center. It is necessary to guide. In particular, these gas flows are affected by the particle size of the raw material and the thickness of the deposited layer (iron ore and coke gas resistance are different).
greatly influenced by. Therefore, in order to operate the blast furnace smoothly, it is necessary to accurately grasp, grasp, and control the position where the raw material is charged and dropped, and various techniques for detecting the position where the raw material falls have been developed.

For example, in the technology shown in FIG. 2, a load detection sensor 2 is installed that penetrates the blast furnace wall 1 and extends toward the center of the blast furnace, and the raw material 4 falling from the raw material charging chute 3 is detected in the longitudinal direction of the load detection sensor 2. A detector 5 connected to the load detection sensor 2 detects the impact when the raw material collides with one of the plurality of sensing parts 2a arranged separately, and determines which of the sensing parts 2a the raw material has collided with. This is to detect and determine the position of the fall. On the other hand, in the technique shown in FIG. 3, a long member 6 coated with a detection paint is inserted into the blast furnace so as to be able to move forward and backward.
The peeling of paint that occurs when the raw material 4 falling from the raw material charging chute 3 collides with the elongated member 6 is detected by pulling the elongated member 6 out of the furnace, and the falling position of the raw material 4 is estimated. It is something.

[Problems to be Solved by the Invention] Although the techniques shown in FIGS. 2 and 3 have achieved certain effects, various problems remain. That is, the technique shown in FIG. 2 (1) has a structure in which the raw material is directly collided with the sensitive part 2a, so the sensitive part 2a is easily damaged; (2) the furnace atmosphere is high temperature and dusty, so it cannot be used. The number of sensitive parts 2a is limited, and the sensitive parts 2a that can be used in such a furnace are necessarily expensive and have poor maintainability. Furthermore, the technique shown in Figure 3 has problems with accuracy because (1) the method estimates the charging position of the raw material from the peeled state of the paint; (2) (3) Long parts that have been used once need to be repainted, so it is impossible to track and detect the falling position over time. It has been pointed out that continuous measurement is difficult, and that continuous measurement requires large-scale equipment and increases costs.

The present invention was made to develop a detection method that does not have the above-mentioned problems, and its purpose is to develop a device that has a simple configuration, can detect with high accuracy, and is also easy to maintain. The present invention aims to provide a method for detecting the falling position of charged raw materials using the method.

[Means for Solving the Problems] The structure of the present invention that can solve the above problems is a method for estimating the charging and falling position of raw materials charged into a rotary chute blast furnace, and The member is inserted in the transverse direction of the blast furnace across the material falling space, and vibration detection sensors of the elongated member are provided at both ends of the elongated member outside the furnace, so that the material falling from the rotating chute is The gist is that the position at which the raw material collides with the elongated member is estimated by reading the time difference until the acoustic vibration generated when the material collides with the elongated member is transmitted through the elongated member and transmitted to each vibration detection sensor. It is something.

[Function] The present invention is constructed as described above, but the key point is that vibration detection sensors are provided at both ends of the elongated member outside the furnace, and the structure is such that the charging material does not directly collide with the sensitive part, so the sensor is not damaged. It is possible to avoid conventional problems such as limitations on the types of sensors used and the types of sensors used. In addition, we have adopted a configuration that reads the time difference until the acoustic vibration generated when the raw material collides with a long member is transmitted to each vibration detection sensor, making it possible to continuously track and detect the charging status. In addition, there is no need to replace the device for each charge, and as a result, it is now possible to always accurately estimate the raw material falling position.

[Example] FIG. 1 is a schematic explanatory diagram showing the main parts of a blast furnace configured to carry out the method of the present invention. A long member 8 is inserted and arranged so as to penetrate the blast furnace wall 1 and cross the inside of the furnace. Both ends of the elongated member 8 are located outside the furnace, and vibration detection sensors 9 and 10 are respectively provided at both ends outside the furnace. Non-limiting examples of the vibration detection element include piezoelectric elements, electrodynamic pickups, and the like. In such a configuration,
By reading the time difference Δt until the acoustic vibration generated when the raw material collides with the elongated member 8 is transmitted through the elongated member 8 and transmitted to each vibration detection sensor 9.10, the elongated member 8 is detected. This is to estimate the collision position.

The measurement principle of the method of the present invention will be explained below with reference to FIG.

Now, the raw material 4 is dropped into the furnace from the raw material charging chute 3,
It is assumed that the raw material 4 collides with the elongated member 8 at point P (collision point). In FIG. 1, L and La.

Lb is as follows.

L - length of long member 8 and distance between vibration detection sensors 9 and 10) La: Distance from collision point P to vibration detection sensor P Lb: Distance from collision point P to vibration detection sensor 10 Here, each vibration detection Let Ta and Tb be the times until acoustic vibrations from the collision point P are observed by sensors 9 and 10, respectively.
If the sound velocity in the elongated member 8 is V, then the following (4), (
2) The formula holds true.

From equations (1) and (2), the following equation (3) holds true■ Here, since L-La+Lb L b = L - L a (4).

The following equation (5) is derived from the above equations (3) and (4).

■ By transforming the equation (5), the following equation (6) is obtained.

From (6) above, it can be considered as follows.

That is, by measuring the difference ΔT (Ta-Tb) between the times Ta and Tb until the vibration is transmitted to each vibration detection sensor 9.10,
The distance from the vibration detection sensor 9 (or 10) to the collision point P can be measured. Furthermore, when measuring the time difference ΔT due to the collision of the same object with the two vibration detection sensors 9 and 10, the time difference ΔT can be calculated by calculating the cross-correlation of the observation data, and the times Ta and Tb can be directly measured. The position of the collision point P can be estimated even if the collision point P is not used. Note that the times Ta and Tb are the sound pressure levels (d
It is sufficient to take the time up to times T1 and T2 when B) takes an extreme value. Their relationships are shown in FIGS. 4 and 5. Furthermore, the signals obtained by each sensor 9.10 by calculating the cross-correlation of the measurement results of the vibration detection sensors 9.10 are
It can also be determined whether the collisions were caused by collisions between the same objects (raw materials).

It should be noted that the temperature inside the furnace differs depending on the area, and there is a concern that the sound velocity inside the elongated member 8 changes in each part, but this is the first problem.
This can be easily solved by setting a plurality of (9 in FIG. 1) thermometers A1 to A9 in the longitudinal direction of the elongated member 8 as shown in the figure, measuring the temperature at each part, and performing temperature compensation. I can do it. Moreover, by this, the falling position of the raw material can be estimated with high accuracy.

In the above embodiment, one elongated member 8 is inserted into the wall of each blast furnace. ), a configuration may be adopted in which a plurality of elongated members are inserted and arranged at intervals at different positions in the circumferential direction. Further, the elongated member 8 does not necessarily have to pass through the reactor core. By employing such a configuration, it is possible to estimate the circumferential variation in the falling position of the charged raw material with even higher accuracy.

[Effects of the Invention] As described above, according to the present invention, by operating according to the method of the present invention, the falling position of the raw material can be detected with high accuracy with a simple configuration, and maintainability is also improved. Ta.

[Brief explanation of drawings]

Fig. 1 is a schematic explanatory diagram showing the main parts of a blast furnace constructed to carry out the method of the present invention, Figs. 2 and 3 are schematic explanatory diagrams showing the prior art, and Fig. 4 is a vibration detection sensor 9 FIG. 5 is a graph showing the relationship between the sound pressure level measured by the vibration detection sensor 10 and time Tb.

Claims (1)

[Claims] A method for estimating the charging and falling position of raw materials to be charged into a rotary chute blast furnace, comprising: inserting and arranging a long member in the transverse direction of the blast furnace across the falling space of the raw materials; Vibration detection sensors for the elongated member are provided at both ends, and acoustic vibrations generated when the falling raw material from the rotating chute collides with the elongated member are transmitted through the elongated member to each vibration detection sensor. A method for estimating the falling position of charged material in a rotary chute blast furnace, characterized by estimating the position where the material collides with a long member by reading the time difference.