Blast furnace burden distribution method for improving agglomerate utilization efficiency

Abstract

The invention discloses a blast furnace burden distribution method for improving the agglomerate utilization efficiency. The method comprises the following steps: 1, weighing and screening agglomerates, returning agglomerates with the particle size of below 3mm as secondary return mines, and sending agglomerates with the particle size of 3mm or more to a blast furnace; and 2, controlling the burden distribution width of the agglomerates in the furnace to meet a condition that the tilting angle position difference in a burden distribution chute is 7-9DEG, and controlling the burden distribution to meet a condition that a distance from the radial edge of the agglomerates in the furnace to the wall of the furnace is 1 / 15-1 / 10 of the internal diameter of a hearth. The method breaks through restriction that the particle size of agglomerates in the furnace is not less than 4mm traditionally, allows the agglomerates with the particle size of 3-4mm to enter the furnace, and improves the small-particle-size utilization rate in order to improve the whole utilization efficiency of the agglomerates, reduce the mine return amount and alleviate the sintering pressure brought by production power; the conversion of an original coke-large particle size agglomerates-small particle size agglomerates three-step grading burden distribution mode to a coke-sintering two-step circulation burden distribution mode simplifies the burden distribution flow and improves the smelting efficiency.

Description

technical field [0001] The invention relates to metallurgical technology, in particular to a method for distributing material for a blast furnace to improve utilization efficiency of sintered ore. Background technique [0002] The general material distribution mode adopted by Wuhan Iron and Steel Blast Furnace is that large-size sinter and small-size sinter are graded into the furnace, and the blast furnace material distribution chute is divided into 11 corners along the radial direction. The material distribution system adopted is generally as follows: Among them, C represents coke, O L Represents large-grained sinter, while O S It represents small-grained sintered ore, the angle difference between the 9th ring and the 5th ring is generally 12°, and the angular position of No. 1 is generally 10°. The incoming materials of the sintering plant are classified according to the particle size D through the grading sieve, and the small sintering O S The particle size of 4mm≤D≤...

AI Technical Summary

Problems solved by technology

[0003] The No. 2 blast furnace was added in Wuhan Iron and Steel Plant in 2011. The increase in the number of blast furnaces and the improvement in the operation level of the blast furnace have increased the pig iron production capacity from 15.8 million tons in 2010 to 17.3 million tons. With the increase in pig iron production capacity, the existing sintering It is difficult to maintain the balance of production capacity, and the problem of insufficient sintering capacity is becoming more and more obvious, and increasing the sintering machine will inevitably increase the investment in equipment. Therefore, how to alleviate the sintering pressure on the basis of not increasing the investment in equipment will be the problem to be solved

[0004] For example, the Chinese invention patent with the application number of 201110316389.7 discloses a method of classifying sinter into the furnace. This method classifies the sinter according to the particle size, and gives the size of the divided particle size and the proportion of sinter with different particle sizes. As well as the material distribution method, this method can effectively improve the air permeability of the blast furnace material column, adjust the reasonable distribution of gas flow, indirectly improve the utilization efficiency of sinter, and relieve the sintering pressure, but this method increases the work in sinter classification In view of the current situation of high ore cost and shortage of raw materials, the use of sinter graded into the furnace will cause the sinter with small particle size to not be better utilized and increase the sintering cost

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