JPS58197207A - Detection of channeling of charge in vertical chute part of charger for blast furnace - Google Patents

Abstract

PURPOSE:To detect the deposition condition of the raw materials in a blast furnace exactly by detecting the falling rate and channeling position of raw materials for a blast furnace with the plural oscillation sensors mounted around the vertical chute of a raw material charger for the blast furnace. CONSTITUTION:Raw materials such as iron ore and coke are scattered and charged from the top bunkers 1, 2 of a blast furnace into the furance by a vertical chute 3 and a swiveling chute 4. Oscillation sensors 6, 7, 8, 9 are mounted at equal intervals around the chute 3 in this case. The falling rate S of the raw materials is calculated by the equation [ I ] from the value PK measured with each sensor in the stage of charging the raw materials, and the channeling position theta of the falling raw materials is calculated by using the equation [II] from the specific largest adjacent measured values Pi and Pi+1 among the values measured with the sensors. The deposition condition of the raw material in the furnace is detected from the values S and theta, and the charging of the raw materials is adequately regulated so as to attain the normal deposition condition, whereby the condition of the blast furnace is stabilized.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for detecting drifting of a charge in a vertical chute of a blast furnace charging device, and in particular, to accurately detect the amount of falling blast furnace raw material falling in a vertical chute and the position of drifting. This is intended to make these factors contribute effectively to the charging of raw materials into the furnace, which is part of the control factors, and to help appropriately adjust the deposition state of the charged materials.

Generally, the heat level inside the blast furnace is closely related to the ore/coke distribution in the raw material accumulation layer (hereinafter simply referred to as 04 distribution), and each part along the circumference of the blast furnace (hereinafter referred to as the circumferential direction) If there is a bias in the 010 distribution, there will also be a difference in the heat level in the circumferential direction of the furnace.

If there is a difference in the heat level state in the direction of the furnace circumference, the blast furnace operation becomes unstable and fuel costs increase. In a blast furnace, differences occur in the temperature and composition of the hot metal tapped from each tap hole, which impairs the smooth processing of the hot metal in subsequent steps.

Recently, a method of charging raw materials into a blast furnace using a rotating chute instead of the bell method has been developed, and has become increasingly popular. However, due to the structure of this rotating chute system, it is difficult to charge the raw material uniformly in the circumferential direction of the furnace, which leaves a problem in that the 010 distribution in the circumferential direction becomes uneven. 2 shows a cross-sectional view of the stacked state of the charge, particularly the 010 distribution state, together with the charging device, when the raw material is charged into the blast furnace using a rotating chute. Numbers 1 and 2 in the figure are both furnace top bunkers, and in this example, ore is discharged from furnace top bunker 1 and coke (8) is discharged from furnace top bunker 2. 3 is a vertical chute, 14
is the rotating chute, and 5 is the wall of the blast furnace.

When raw materials are charged using the above-mentioned charging equipment, the following problems occur. That is, when the raw materials discharged from the furnace top bunkers 1 and 2 pass through the vertical and vertical chutes 8, they drift and fall within the vertical chutes 8, depending on the installation position of the furnace top bunker used. As a result, the raw material will fall at different positions on the rotating chute 4 depending on the rotation angle of the rotating chute 4, so the moving distance of the raw material on the rotating seat/neat 4 will be from d□ to d2. It changes with For this reason, differences occur in the moving time of the raw material on the rotating chute 4, as well as the speed and direction when leaving the chute 4, as shown by vectors v and v' in the figure, and ultimately the There was a bias in the layered state of the charges in the circumferential direction, that is, a bias in the 010 distribution in the furnace circumferential direction as seen in the deposited layer profile shown in No. 119.

Therefore, in order to correct the imbalance in the accumulation state of the contents in the reactor, changes should be made to the charging method by, for example, changing the bunkers used, and (4) adjusting the rotating speed and direction of the rotating chute. Many attempts have been made to improve and homogenize the state of the charge piled up in the furnace.

By the way, in all of these improvement measures, it is especially important to accurately grasp the drift state of the charge as it passes through the vertical chute, that is, the falling amount and drift position, but so far it has not been possible to accurately Currently, no detection method has been developed.

The present invention advantageously meets the above-mentioned needs by proposing a method for detecting drifting of a charge material, which makes it possible to accurately detect the drifting state 1 when a blast furnace raw material falls into a vertical chute. .

That is, in the blast furnace charging in which the blast furnace raw material discharged from the furnace top bunker is passed through the entire vertical chute and charged into the furnace using the rotating chute, the vertical chute, along the outer periphery of the neat? At least three vibration sensors arranged at equal intervals are used to measure the vibrations of the vertical shoe and do when charging raw material into the blast furnace, and the following (1) and (2) are calculated from each measurement value obtained.
) The drifting flow of the charge in the vertical chute part of the blast furnace charging equipment is characterized in that the falling MS of the charge and the drifting position θ are calculated respectively to detect the charging 1 and the drift of the material. It is a detection method.

Here, α: Constant that varies depending on the name of the blast furnace raw material 7: Squid 47 t -47) fm & □ ゛□Pk
: Measured values Pi, Pi+t : Two of the measured values with the largest outputs n, m: Constants □ θ: Angle between the sensor that outputs P1 and the center of gravity of the charge J This invention will be explained in detail below. do.

FIG. 2 shows a cross section of the vertical chute when a 4fiI vibration sensor is installed along the outer periphery of the vertical chute, along with a calculation system for the measured values, and FIG. 8 shows the details of the main parts. In the figure, 6.7.8 and 9 are vibration sensors.

Assume now that the charge is falling through the vertical chute as a drifted flow along the inner wall of the chute as shown in FIG. At this time, the magnitude of the vibration of the vertical chute is proportional to the amount of fall. Therefore, by calculating the sum of the measured values measured by each vibration sensor as shown in Equation 15 below, it is possible to always know the accurate falling amount S regardless of the drift position of the charge.・α: Constant that varies depending on the brand of blast furnace raw material n: Constant Also, at the place shown in Fig. 8, Pi is the measured value of two vibration sensors that sandwich one drifting position of the charge.

Assuming P1+1, pi, , Pi+x correspond to the two with the largest measured values among the four vibration sensors, as shown in FIG.

Here, when the angle between the installation position of the vibration sensor that measures Pi and the center of gravity of the raw material at 0 dimensions is θ, and the radius of the vertical chute 81 is R, the attenuation of vibration is inversely proportional to the distance m-th power, so pi , , pi+x are each where m:
It is expressed as a constant, so the ratio of pi and pi+1 "i/Pi+1
becomes I...

In other words, when measuring the vibration of a vertical chute using four vibration sensors, two of the largest measured values are used as Pi.
, by substituting Pi+1 into equation (2) 7 above, the drift position of the charge in the vertical chute is positive...

Such calculations can be easily calculated and displayed using the calculation system shown in FIG. 12 above.

Although the above explanation has mainly been based on the case where four vibration sensors are used as a typical example, the present invention is not limited to the above case, and can be similarly applied to any case where the number of vibration sensors is eight or more. This invention can be applied as a lever. If the number of vibration sensors used at this time is l, then [(1)
Equations ' and (2)' are each expressed as the following equation (1) as a general equation:
, expressed as (2). Thus, according to the present invention, when charging a blast furnace using a rotating chute, it is possible to accurately grasp the falling amount and drift position of the charge when it passes through the vertical chute, and therefore It is effective when adjusting the charge deposition state in the blast furnace as part of the control factor.

[Brief explanation of the drawing]

Figure 1 is a sectional view showing the stacked state of blast furnace raw materials charged into the furnace according to the conventional method, together with the charging equipment, Figure 2 is a calculation system diagram showing the processing system for the measured values of the vibration sensor, Figure 3 is a cross-sectional view of the vertical chute, and Figure 4 is a graph showing the difference in measured values due to the difference in the V position of the vibration sensor. Patent applicant Kawasaki Steel Corporation Figure 3 Figure 4

Claims (1)

[Scope of Claims] L In blast furnace charging in which the blast furnace raw material discharged from the furnace top bunker passes through a vertical chute and is charged into the furnace using a rotating chute, the blast furnace material is placed at equal intervals along the outer periphery of the vertical chute. At least 8 vibration sensors measure the vibration of the vertical chute during charging of raw material into the blast furnace, and from each measured value the following formulas (1) and (2) are used to determine the fall of the charge. A method for detecting drifting of the charge in a vertical chute of a blast furnace charging device, characterized in that drifting of the charge is detected by calculating the amount S and the drifting position θ2. Here, α: Constant that varies depending on the brand of blast furnace raw material l: Number of vibration sensors Pk: Measured value pi, p soil + 1: Two of the largest outputs among the measured values n, m: Constant θ: Output Pi The angle between the sensor and the center of gravity of the charge