Grading and quality-dividing material distribution method in blast furnace

Abstract

Modern blast furnaces become upsized continuously, and thus, the situations that centers cannot be blown thoroughly (dead stocks are poor in air permeability), the utilization rate of coal gas is low,and the fuel ratio stays at a high level happen frequently. The primary cause is particle segregation of a paralleled pot, a large amount of small-size coke and small-size ore enter the center of a blast furnace or an annular zone near the center, and the air-permeability of the blast furnace and reduction of the ore are severely affected, which is extremely unfavorable to iron-making productionof the blast furnace. Therefore, the invention provides a grading and quality-dividing material distribution method in a blast furnace according to an existing material distribution system, crude fuelof different grades and different weights can be loaded into different radial positions of the blast furnace according to smelting requirements, and the problem is solved. The technological process is simple and controllable, the grading and quality-dividing effect is excellent, in addition, little investment and modification are applied to existing equipment, and the process that the crude fuelis loaded into the furnace in the graded and quality-divided mode is conducted effectively and continuously.

Description

technical field [0001] The invention belongs to the field of metallurgical technology research and improvement, and in particular relates to a method for classifying and distributing material in a blast furnace. Background technique [0002] In order to save energy and protect the environment, and improve economic benefits, modern blast furnaces continue to be enlarged, even reaching 6000m 3 level. However, the hearth and bosh of large blast furnaces have large diameters, resulting in impermeable central blowing (poor air permeability of the dead material column), low gas utilization rate, and high fuel ratio. The root cause is the particle size segregation of the tank-combining material distribution system, which causes a large amount of small-sized coke to enter the central area of ​​the blast furnace, and gradually enters the dead material column as the charge descends. With the progress of the smelting process, the coke particle size in this part of the central area bec...

AI Technical Summary

Problems solved by technology

However, the hearth and bosh of large blast furnaces have large diameters, resulting in impermeable center (poor air permeability of dead material column), low gas utilization rate and high fuel ratio

The root cause is the particle size segregation of the tank-combining material distribution system, which causes a large amount of small-sized coke to enter the central area of ​​the blast furnace, and gradually enters the dead material column as the charge descends. With the progress of the smelting process, the coke particle size in this part of the central area becomes smaller, further deteriorating the air permeability of the dead column

For ores, the same problem exists. Due to the existence of segregation, small-sized ores will concentrate in one or several rings, and sometimes even enter the sub-center or even the center of the blast furnace with the collapse of coke, resulting in local areas Fluidization occurs, the airflow is disordered, and the airflow in some areas is weak or even no airflow, which is very unfavorable for ore reduction

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