JPH04308012A - Blast furnace raw material charging method and equipment - Google Patents

Abstract

PURPOSE:To freely control the distribution of charging raw materials, etc., without overflowing them from a swing chute even if the swing chute in a belless blast furnace directs just downward. CONSTITUTION:The raw materials 8, etc., are charged into the whole range of charging position from the outer peripheral part to the center part in a furnace with cylindrical type, etc., of the swing chute 4. As the swing chute 4 can be used in the optional inclination and the distribution of raw materials, 8, etc., can be thickened, the raw material layer having good ventilation control, etc., can be formed.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] This invention allows the charging speed to be freely selected when charging raw materials into a blast furnace, and as a result, the stacking angle of the raw materials in the furnace, the ratio of iron source to fuel in the radial direction, the radius This invention relates to a rotating chute that can improve the controllability of directional particle size distribution.

0002

2. Description of the Related Art A conventional rotating chute in a bellless type blast furnace has a gutter-like shape as shown in FIG. When this rotating chute 4 faces straight down, metallurgical raw materials overflow. Also, when giving a turning motion, overflowing as shown in FIG. 5 has been observed. Therefore, since conventional swing chutes must be used at a fixed angle of inclination, various improvements were required.

[0003] A device was proposed in Japanese Patent Laid-Open No. 1999-1, which aims to improve the controllability of the deposition angle of metallurgical raw materials, the ratio of iron source to fuel in the radial direction, and the particle size distribution in the radial direction in the furnace of a bellless type blast furnace. This is disclosed in Japanese Patent No.-123013. That is, "an opening is formed at the lower end of the rotating chute, and a plurality of bars extending across the opening in the radial direction of the furnace are provided below the rotating chute, and the mutual gap between these bars is defined by the A raw material charging device characterized in that the chute is smaller at the lower end side and larger at the tip side of the bar and strip, and the raw material is charged into the furnace by passing the raw material through the tip of the rotating chute. It is possible to form a particle size distribution suitable for the reaction conditions in the furnace. FIG. 6 shows how this conventional rotating chute 51 operates in a furnace. As a result, the raw material passing through the bar screen installed at the lower end of the rotating chute falls at various locations with a narrow particle size distribution. The raw materials are stacked on top of each other without applying kinetic energy that would break them down.The raw material packed bed formed in this way ensures ventilation inside the furnace, making it possible to process raw materials with high reaction efficiency. ”.

0004

[Problems to be Solved by the Invention] However, according to the above-mentioned publication, ``Due to the distribution of raw material discharged from the bell and the segregation caused by rolling on the layer of raw material already charged in the furnace, A distribution with particle size differences is formed.'' Here, the proposal in the above publication was made in an attempt to control segregation due to rolling on the raw material layer already charged in the furnace by a bar screen. Raw materials cannot be distributed freely in the radial direction within the furnace.

The present invention was made in view of the above circumstances, and an object thereof is to provide an apparatus capable of forming a raw material packed bed suitable for reaction conditions in a furnace.

[0006]

[Means for Solving the Problems] A material charging device for a blast furnace according to the present invention is characterized in that, in a rotating chute provided at the top of a bellless type blast furnace, the rotating chute has a cross section of a cylindrical body. shall be. Furthermore, by using the rotating chute, the position where the charge falls onto the charge covers the entire range from the outermost periphery of the furnace to the center of the furnace, thereby reducing the accumulation of charge in the furnace. It is characterized by the fact that the charge does not roll on the slope of the mountain.

[0007]

[Operation] Since the rotating chute has a cylindrical cross section, it does not overflow, and the rotating chute can be used at any angle of inclination.

[0008] Furthermore, since the charge does not roll on the slope of the mountain where the charge is piled up in the furnace, the particle size distribution of the charge and the iron ore and coke are uniform from the outermost periphery of the furnace to the center of the furnace. The ratio can be freely controlled.

[0009]

[Embodiment] Fig. 1 shows a cylindrical rotating chute according to an embodiment of the present invention.
, will be explained with reference to FIGS. 2 and 3. FIG. 1 is an explanatory diagram showing a part of the furnace top 6 of the bellless type blast furnace of the present invention in a vertical cross section. FIG. 2 is a perspective view of the cylindrical rotating chute of the present invention. FIG. 3 is a perspective view of the gutter-type rotating chute of the present invention. The metallurgical raw material conveyed by the belt conveyor 7 falls in the direction indicated by the arrow 11, passes through the upper seal valve 1, and is stored in the fixed hopper 2. Then, the upper seal valve 1 is closed and the rear lower seal valve 3 is opened. There, the metallurgical raw material falls in the direction indicated by arrow 12, passes through the pivoting chute 4, falls in the direction indicated by arrow 13, and falls into the furnace to form stock line 9. In the figure, 5 is a riser pipe for B gas.

In this embodiment, the above-mentioned operation is repeated four times to charge one charge of iron ore, and the amount of iron ore charged in one charge is 120 Ton to 150 Ton.
Met. The rotating chute 4 is rotating at 7.53 rpm. During the charging of one charge of iron ore, there are normally 16 turns of the swinging chute 4.

[0011] When charging metallurgical raw materials, in order to avoid segregation due to rolling on the raw material layer that has already been charged into the furnace, it is necessary to It is necessary that the metallurgical raw material is evenly distributed directly from the rotating chute 4 to the stock line 9 without rolling on the raw material layer, but the cylindrical rotating chute of the present invention has a cylindrical cross section or a trough. Since it is composed of a lower structure having a mold-shaped cross section and an upper structure that covers the lower structure without any gaps, the rotating chute 4 does not overflow even when heading directly downward, and even when applying centrifugal force due to rotation. Because there is nothing to do. As a result, the metallurgical raw materials are evenly distributed to the stock line 9. In addition, since the swing chute 4 must withstand impact force and wear, it is made of high manganese steel in this embodiment.

Furthermore, by setting the number of turns of the rotating chute 4 to about 10 during charging of one charge of metallurgical raw materials, the thickness of the layer of metallurgical raw materials formed by one passage of the rotating chute 4 can be increased. I can do that.

[0013]

[Effects of the Invention] This invention makes it possible to avoid the overflow of raw materials in the rotating chute, so the rotating chute can be used at any angle of inclination, and the number of turns of the rotating chute during charging of one charge of raw material can be reduced. By reducing the amount, the thickness of the raw material layer can be increased, so that a raw material packed bed suitable for the reaction conditions in the furnace can be formed.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram partially showing a vertical section of the top of the blast furnace of the present invention.

FIG. 2 is a perspective view of the cylindrical rotating chute of the present invention.

FIG. 3 is a perspective view of the gutter-type swing chute of the present invention.

FIG. 4 is a perspective view of a conventional swing chute.

FIG. 5 is an explanatory diagram showing a conventional swing chute in cross section.

FIG. 6 is an explanatory diagram showing the operation status of another conventional example of a rotating chute in a furnace.

[Explanation of symbols]

1 Upper seal valve 2 Fixed hopper 3 Lower seal valve 4 Rotating chute 5　B gas riser pipe 6　Furnace top of bellless blast furnace 7 Belt conveyor 8 Metallurgical raw materials 9 Stock line 10　Gutter type rotating chute 11 Arrow indicating the falling direction of metallurgical raw materials 12 Arrow indicating the falling direction of metallurgical raw materials 13 Arrow indicating the falling direction of metallurgical raw materials 51 Rotating chute

Claims (2)

[Claims] 1. A material charging device for a blast furnace, wherein the rotating chute is provided at the top of a bellless type blast furnace, and the rotating chute has a cylindrical cross section. [Claim 2] By using the rotating chute according to claim 1, the raw material of the blast furnace is dropped onto the charge over the entire range from the outermost periphery of the furnace to the center of the furnace. , a method for charging raw materials in a blast furnace, characterized in that the charge does not roll on the slope of the mountain on which the charge is piled up in the furnace.