JPH05279716A - Method for charging material to be charged into blast furnace - Google Patents

Abstract

PURPOSE:To effectively utilize waste, such as scale containing much iron and also large content of Zn, etc., and to extend the service life of a blast furnace. CONSTITUTION:In the case of avoiding deposition on the furnace wall 7, high Zn sintered ore 9 is charged into the furnace from a furnace center charging chute 4a and the gasified ZnO is discharged from the furnace top to the furnace outer part together with dust. In the case of making the profile sound by depositing the stuck material to the worn part of the furnace wall 7, the high Zn sintered ore 9 is charged into the furnace from a furnace wall side charging chute 4b, and the gasified ZnO is cooled and resolidified on the furnace wall 7 and deposited on the worn part of the furnace wall 7.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of charging a blast furnace when a scale containing a large amount of Zn, which is discarded in a plating step, is charged as a part of the ironmaking raw material.

[0002]

2. Description of the Related Art Stable reduction of ore in blast furnace operation,
In order to melt, it is essential to maintain the gas flow distribution in the shaft part of the blast furnace and the unloading of the charging materials such as ores and coke in an appropriate state. It is necessary to keep in profile.

On the other hand, when the charge contains a large amount of Zn or the like having a low vaporization temperature, the vaporized charge of Zn is found in the core.
O is discharged to the outside of the blast furnace together with dust, but ZnO vaporized near the furnace wall is cooled by the furnace wall and re-solidifies and adheres, so that the Zn content of the charge becomes a problem. Therefore, in the conventional blast furnace charging, for example, the amount of Zn charged into the blast furnace is 0.2 kg /
The Zn content in the sinter is controlled to be less than 0.017%.

[0004]

Conventionally, the charging of the blast furnace has been controlled as described above, so that, for example, a scale containing a large amount of an iron source is generated as waste in a plating process in a pig iron factory. , Since this scale contains a large amount of Zn, it has been discarded without being effectively used as a charge to the blast furnace.

The present invention has been made to solve the above problems, and Zn re-solidified and adhered on the furnace wall
It is an object of the present invention to provide a method for charging a blast furnace charge, which enables effective utilization of waste such as scale having a large content of such components as well as obtaining the effect of extending the life of the blast furnace.

[0006]

In the method for charging a blast furnace charge according to the present invention, a charge containing a component that vaporizes in the furnace is charged as a part of the raw material into the blast furnace from the top of the furnace. In the method, when avoiding adhesion of the re-solidified material of the component to the furnace wall, the charge is charged into the core, while when charging the re-solidified material of the component to the furnace wall, the charging is performed. It is characterized in that an object is charged near the furnace wall.

[0007]

The method of charging a blast furnace charge according to the present invention vaporizes in the furnace like a scale containing a large amount of iron but a large amount of Zn, which is generated as a waste in the plating step. When a charge containing a large amount of ingredients is directly or mixed with sinter ore and charged into the blast furnace as a part of the raw material, this charge is used when the profile of the furnace wall is sound due to the short operating time of the blast furnace. By loading the material into the core, the vaporized components are discharged together with dust from the top of the furnace to the outside.On the other hand, if the erosion of the furnace wall is progressing due to the blast furnace's long service life, etc. By charging near the furnace wall, the vaporized components are cooled by the furnace wall and adhere to the eroded portion to make the profile of the furnace wall sound.

[0008]

The present invention will be described below with reference to the drawings showing the embodiments thereof. FIG. 1 is a partial cross-sectional view of a blast furnace for carrying out a method for charging a blast furnace charge according to the present invention (hereinafter referred to as a method of the present invention), in which 1 is a blast furnace shaft having a furnace wall 7 made of refractory bricks. Is. The high-Zn sinter 9 containing an iron source and mixed with a scale containing a large amount of Zn in a sintering process (not shown) and sintered was carried by a belt conveyor to the receiving hopper 2 at the top of the blast furnace and the charging amount was changed. Through a charging hopper 3 provided with a valve for adjusting, it is charged into the reactor from a core charging chute 4a to the core or a reactor wall charging chute 4b near the reactor wall.

On the other hand, the charge 6 having the adjusted Zn content is carried on the large bell 5, and the large bell 5 slides downward to form a layer and be charged into the furnace. High Zn sinter 9
Is charged into the core portion or the vicinity of the furnace wall at each charging or every predetermined number of chargings between charging with the large bell 5. The high-Zn sintered ore 9 charged into the core portion by the core charging chute 4a is vaporized in the furnace and discharged with dust from the furnace top to the outside of the blast furnace, and is loaded into the vicinity of the furnace wall 7 by the furnace wall charging chute 4b. The high-Zn sintered ore 9 that has entered is vaporized, cooled on the furnace wall, resolidified, and adheres.

FIG. 2 is a partially enlarged view of the blast furnace showing an implementation process of the method of the present invention for adhering a Zn re-solidified product to a furnace wall where erosion has progressed. In the drawing, 8 is a heat load from inside the furnace. A stave cooled with water passing through the pipe of No. 10, 10 is a ZnO deposit.

A blast furnace (effective internal volume 2700 m ³ , operating years 4
It was confirmed that a part of the furnace wall 7 on the stave 8 had largely fallen off when the inside of the furnace (1 year) was observed when the blast furnace was off. While installing the furnace wall charging chute 4b in the direction corresponding to the worn part of the furnace wall, a large amount of scale (Zn ≈ 3%, Fe> 90%) generated at the plating plant in the steel mill was mixed with the sintered ore raw material. To produce sinter (Zn> 0.5%), and store this sinter in a yard.

After the air was blown for 45 days, the above-mentioned sinter was sintered once every 4 hours from the furnace wall charging chute 4b as shown in FIG. 2 (a).
Continued charging 00kg. When the inside of the furnace was observed after a 45-day quiescent period, it was confirmed that the ZnO deposit 10 was deposited on the furnace wall 7 in an appropriate amount to make the profile healthy, as shown in FIG. 2 (b). The composition of the deposit 10 was mainly ZnO (about 85%), and the others were Na ₂ O, K ₂ O, FeO and the like.

After this dead air, the furnace wall charging chute 4b was replaced with the core charging chute 4a, and the above-mentioned sinter was continuously charged into the core for about 6 months, after which the inside of the furnace was observed. Wall 7
No excessive deposits were observed, and the ZnO deposit 10 was in good condition without falling off.

In this embodiment, the case of processing into a high-Zn sintered ore and charging it into the blast furnace is explained, but the high-Zn raw material such as scale may be directly charged into the blast furnace without being sintered. ,
The same effect as the present embodiment can be obtained.

[0015]

INDUSTRIAL APPLICABILITY As described above, according to the method of the present invention, the waste containing a large amount of iron sources such as scales in the plating step can be effectively reused as a part of the raw material, and the furnace wall partially removed due to erosion. In addition, since the waste is charged in the vicinity of the furnace wall so that the vapors of the components contained in the waste are re-solidified and adhered, the excellent effect of extending the life of the blast furnace can be obtained.

[Brief description of drawings]

FIG. 1 is a partial sectional view of a blast furnace for carrying out the method of the present invention.

FIG. 2 is a partially enlarged sectional view of a blast furnace showing a process of carrying out the method of the present invention.

[Explanation of symbols]

 1 Blast furnace shaft 2 Receiving hopper 3 Charging hopper 4a Core charging chute 4b Furnace wall charging chute 5 Large bell 6 Charge 7 Furnace wall 8 Stave 9 High Zn sinter 10 ZnO deposit

Claims (1)

[Claims] 1. A method of charging a charge containing a component that vaporizes in a furnace into a blast furnace from a furnace top as a part of a raw material, avoiding adhesion of a re-solidified product of the component to the furnace wall. In the case where the charge is charged into the core portion, when the re-solidified product of the component is attached to the furnace wall, the charge is charged in the vicinity of the furnace wall. Charging method.