JPS6096706A - Blast furnace raw material charging method - Google Patents

Abstract

PURPOSE:To uniform raw materials to be charged in the circumferential direction in a blast furnace and to stabilize the furnace operation by a method in which difference of gas flow balance in the circumferential direction in the furnace is obtained, and the revolution speed of a rotary chute is relatively adjusted. CONSTITUTION:Detection terminals of thermocouple thermometers, etc. are fitted at proper intervals in the circumferential direction of the main body of a blast furnace 1. From the information at these terminals, the difference of gas flow balance in the said direction in the furnace 1 is obtained. When the rotary chute 4 passes just above the large portion of the gas flow at the time of charging coke, the revolution speed of the chute 4 is relatively increased more than when it passes other positions. Or after obtaining the difference in the height level of charges in the circumferential direction in the furnace, when the chute 4 passes just above the higher part of the level, its revolution speed is increased. Either the gas flow distribution in the circumferential direction in the furnace or the surface level of the charges is uniformized by this method.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention is a bell-type charging device in which the charging material is uniformly squeezed in the circumferential direction into the blast furnace by a rotating chute installed at the top of the top charging device. This relates to improvements in the method for narrowing down the raw materials for blast furnaces.

An example of a prior art bell-type charging device is shown in FIG. It is essential for vortex furnace operation to uniformly distribute raw materials in the circumferential direction inside the blast furnace (1), and for this purpose, the mounting of Tetsujin Bell i-2 prevents raw material charging segregation caused by direction. It has to be resolved.

As equipment for this purpose, from the charging belt 2 to the fixed hopper 3
A rotating 7-ute 4 is installed in the raw material charging process.

This rotating chute 4 connects the charging belt 2 to the fixed hopper 3.
The conventional method is to charge the raw material uniformly into the fixed hopper 3 by constantly rotating the fixed hopper 3 at a constant rotational speed and in a constant rotational direction. However, in the conventional method, the raw material discharge speed from the rotating chute and the charging belt differs depending on the angle between the rotating chute and the charging belt when the rotating chute rotates. Uniform charging is not obtained. This is especially noticeable when charging coke, and if the rotating chute comes in the direction opposite to the charging belt, the coke removal speed from the rotating chute will increase; In this case, the coke dispensing speed becomes smaller. Therefore, in the opposite direction of the charging belt, the ore/coke ratio becomes small and the gas flow develops, whereas in the direction of the charging belt, the ore/coke ratio becomes large and the gas flow is suppressed.

In addition, if a charging method with such charging segregation is continued for a long time, differences in the surface height of the charge will occur in the circumferential direction of the furnace, resulting in operational problems such as blow-through. There is also a risk of causing trouble.

OBJECTS OF THE INVENTION The present invention eliminates the difference in the ore/coke ratio in the circumferential direction of the furnace and the unbalance in the height level of the charge, which occur when raw materials are discharged from the rotating chute. It is for.

Structure and operation of the invention The details of the present invention will be explained below.

The present invention is designed to detect differences in gas flow balance in the circumferential direction of the furnace due to the above-mentioned phenomenon. Based on the information, except when the rotating chute passes directly above the gas flow rate area during the coke iron man, the rotation speed of the rotating chute is increased slidingly at other positions as well. When passing directly above a small portion of be.

-! If there is a difference in the height level of the charge in the furnace in the circumferential direction, this can be detected by sounding in advance, or the change in gas flow distribution caused by the difference in the height of the charge can be measured in the circle of the furnace body. It is detected by the detection edge information provided at appropriate intervals in the circumferential direction, and when the rotating chute passes directly above the part where the height of the charge is insufficient, both during ore iron processing and coke charging, the rotation of the rotating chute is detected. The speed is made relatively high, the amount of raw material discharged in this direction is suppressed, and the unbalance in the height level of the contents in the furnace in the circumferential direction is adjusted.

Here, as a detection end to balance the gas flow rate, a thermocouple thermometer embedded in the furnace brick, a Zstave thermometer, an in-furnace gas component analyzer with a sonde, or a cross-sonde at the top of the furnace are effective. It is. Of course, the information that determines the rotation speed in the circumferential direction of the rotating chute is not only the gas flow balance in the circumferential direction in the furnace, but also data on the thickness of the iron layer in the furnace, hot metal temperature balance at the tap hole, and hot metal composition balance. The same is true.

EXAMPLES Next, practical examples of the present invention will be shown. When charging raw materials from the charging belt to the fixed hopper, the circumferential balance of the thermocouple mixed layer embedded in the 1SIfP81/'' abdomen brick when charging was carried out using the conventional method of rotating the rotating chute at a constant speed was Second
It was as shown in the figure. At this time, the thermocouple temperature is high on the 90-degree side opposite to the charging belt, and the gas flow rate in the furnace is high; It was rarely in a depressed state. Under this condition, the swing motor of the swing chute was replaced with a variable motor, and a sequencer was combined with this to keep the swing speed of the swing chute constant at all times, and only when charging coke as shown in Figure 3. On the 90 degree side where the gas flow rate is high, increase the rotation speed of the rotation chute to 12rpI11,
The amount of coke discharged to the o degree side was suppressed, the ore/coke ratio was relatively controlled, and the gas flow rate was controlled, and the rotating speed of the rotating chute was lowered to 6 rpm on the 270 false side.
Increase the amount of coke discharged to the 0 degree side and relatively reduce the amount of ore/
Decrease coke ratio and increase gas flow rate. By adjusting the thickness of the coke layer in the circumferential direction in the furnace by adjusting the rotation speed of the rotating chute, an operating state with uniform thermocouple temperature and uniform gas flow distribution as shown in Figure 4 was obtained. .

Conversely, the same result can be obtained by keeping the rotating speed of the rotating chute constant during coke charging and varying the rotating speed of the rotating chute in the circumferential direction during ore charging.

Effects of the Invention According to the present invention, it is possible to uniformize the charging material in the circumferential direction of the furnace in a bell type blast furnace material charging device having a rotating chute, which greatly contributes to stabilizing the blast furnace operation. , the effect is tremendous 0

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram of a bell-type blast furnace raw material charging device, Fig. 2 is a diagram showing the thermocouple temperature balance in the furnace belly brick in the conventional method, and Fig. 3 is the rotating speed in the circumferential direction of the rotating chute according to the present invention. FIG. 4 is a diagram showing the internal thermocouple temperature balance of the furnace belly brick improved by the present invention. l...Blast furnace 2...Charging belt 3...Fixed hopper 4...Swivel chute Applicant: Nippon Steel Corporation Ni8 Figure 1 Maruyama Hōkuzangeki

Claims (2)

[Claims] (1) In a bell-type blast furnace raw material charging device with a rotating chute, the difference in gas flow rate balance in the same circumferential direction of the blast furnace r can be estimated by information on multiple detection ends provided in advance at appropriate intervals in the circumferential direction of the furnace body. , when charging coke, when the rotating chute passes directly above a large portion of gas flow rate, the rotating speed is relatively increased to 7 units compared to other positions; Charging device. (2) In a bell-type furnace material charging device with M rotating chute, the furnace top is loaded in advance using furnace top sounding data or information on multiple detection ends provided at appropriate intervals in the circumferential direction of the furnace body.・During raw material charging, when the rotating chute passes directly above a part with a high charge height level, it is higher than other positions. A blast furnace raw material charging method characterized by relatively increasing the rotation speed of a rotation chute.