JPS6028672Y2 - Blast furnace top charging device - Google Patents

Description

[Detailed description of the invention] This invention relates to the distribution performance of charged raw materials through the rotating chute at the top of blast furnaces.In particular, the particle size distribution of the raw material charged into the fixed hopper is non-uniform, which is a major problem with conventional rotating chutes. In order to solve this problem, this is related to a blast furnace top charging device using a rad chute to a conveyor equipped with a repulsion plate that can move back and forth in the center of the front of the conveyor jute, with the aim of uniformizing the particle size distribution of the raw material falling from the conveyor. Out.

Conventionally, the raw material charged to a blast furnace is transported to the top of the furnace by a belt conveyor, falls to the conveyor installed at the top of the furnace via a rad chute, and falls into the material receiving part in the rotating chute. Attempts have been made to achieve uniform distribution in the circumferential direction.

However, when the raw material is distributed into a fixed hopper, it has been confirmed that the circumferential balance of the charged raw material distribution is disrupted when the raw material is charged immediately before blast furnace firing or in model experiments.

If this circumferential balance of the charging material distribution is disrupted, in actual operation it will result in uneven upward gas flow within the charging material.
This lowers the utilization rate of the gas in the furnace for the reduction reaction, leads to a reduction in the fuel ratio, and even causes instability in the furnace condition.

As a result of investigating the causes of uneven circumferential balance of the particle size distribution of the burden through model experiments, it was found that the charge material undergoes particle size classification on the belt conveyor while being conveyed to the top of the blast furnaces, and is transferred to the conveyor via the rad pulley and the rotating chute discharge port. It was confirmed that this tendency is promoted by the relative positional relationship with

This will be explained with reference to FIG.

FIG. 1 shows how the charged raw material 6, which has been subjected to particle size classification, is being discharged from the ped pulley 2 on the belt conveyor 1 as it falls.

The raw material falling from the head pulley 2 passes through the raw material receiving parts 4 and 1 of the rotating chute to the chute part 4-2 of the rotating chute.
It is then distributed into the fixed hopper 5.

However, the raw material 6 falling from the blade pulley exhibits fine grain size segregation on the belt conveyor 1 side, and particle size classification is facilitated by collision with the raw material receiving portion 4-1 of the rotating chute.

When the chute section 4-2 of the rotating chute is on the side opposite to the belt conveyor (the position indicated by the solid line in Fig. 1), the particle size distribution of the raw material falling from the chute section is such that the bottom flow is a distribution of fine particles, and the chute section 4-2 is When the raw material is on the belt conveyor side (the position indicated by the two-dot chain line in FIG. 1), the particle size is mixed at the chute section 4-2, and the particle size segregation of the raw material falling from the chute section is alleviated and distributed.

Therefore, the charged raw material in the fixed hopper 5 has particle size segregation both in the circumferential direction and in the radial direction.

In addition, since the raw material falling from the head pulley has a velocity component force in the horizontal direction and does not fall onto the reactor core, the chute section 4
The flow path of the raw material changes depending on the position -2, and the flow resistance differs, so the amount of raw material discharged from the chute varies and the amount deposited in the circumferential direction also becomes non-uniform.

The present invention is provided to solve the problems of conventional devices, and as mentioned above, the particle size classification of the charged material on the belt conveyor and the fixation caused by the mutual positional relationship between the belt conveyor and the chute part of the rotating chute. The aim is to eliminate grain size segregation in the hopper, but there are many types of raw materials charged to the blast furnace, such as ore, sintered ore, pellets, and coke, and their grain characteristics differ, so the falling characteristics differ.

Furthermore, since the production volume required of the blast furnace changes daily, the amount of raw material charged also varies widely during daily operations.

The amount of raw material charged has a large effect on the falling characteristics.

In this way, the aim is to make the particle size distribution of the raw material falling from the chute uniform in the thickness direction regardless of the combination of the type of raw material charged and the amount charged.

Next, the device of the present invention will be explained based on an example shown in FIGS. 2 and 3.

The present invention is to install a charging material repelling plate that can move back and forth in front of the rad chute on the conveyor.

FIG. 2 shows how the charged raw material falls from the head pulley 2 via the repulsion plate 7 to the raw material receiving portion 4-1 of the rotating chute.

It is well known that when a part of the falling raw material is repelled, the falling trajectory changes and the particle size distribution also changes, and the particles repelled by the repelling plate 7 are coarse particles classified on the belt conveyor 1.

Therefore, the particle size distribution of the raw material falling from the repulsion plate 7 is made uniform by the mixing action.

The conveyor head chute 3 on which the repulsion plate 7 is installed is a fixed part, and it is easy to supply a driving source to the repulsion plate actuator 8 (for example, a hydraulic cylinder, etc.), so it is possible to set the conveyor head chute 3 that is optimal for the type or amount of charging material. The amount of protrusion of the repulsion plate 7 can be adjusted for each condition.

Further, the velocity component force in the horizontal direction of the raw material falling from the head pulley 2 can also be adjusted by the repulsion plate 7, so that the raw material can be dropped vertically onto the reactor core in one direction of the conveyor.

In the perpendicular direction of the conveyor, the conveyor chute has a bifurcated structure as shown in Fig. 3, and the raw material from the head pulley 2 is dropped into the left and right raw material receiving parts 4-1, and is placed in the chute part 4-2. Regardless, the flow path of the raw material in the chute portion 4-2 is made uniform, and it is also effective in eliminating non-uniformity in the amount of accumulation in the circumferential direction.

In the figure, 5 is a fixed hopper, 6 is a raw material to be charged, and 9 is a bell rod.

As described in detail above, according to the present invention, although it has an extremely simple configuration, it is possible to eliminate the imbalance in the charging material distribution caused by the conventional rotating chute, and it is also possible to It has the effect of being able to obtain an appropriate charging distribution without being shifted, and has great practical value.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of a conventional device, FIG. 2 is an explanatory diagram of the device of the present invention, and FIG. 3 is a sectional view taken along the line A--A in FIG. 1 is a belt conveyor, 2 is a rad pulley to the conveyor, 3 is a conveyor chute, 4-1 is a raw material receiving part of a rotating chute, 4-2 is a chute part of a rotating chute, 5 is a fixed hopper, 6 is a charging raw material, 7 is a A raw material repulsion plate, 8 an actuator for the repulsion plate, and 9 a bell rod.

Claims (1)

[Scope of utility model registration request] In a blast furnace top charging device in which raw material is charged into a rotating chute provided on a fixed hopper via a conveyor head chute, a raw material repellent that can be moved back and forth is installed on the front part of the conveyor head chute. A blast furnace top charging device characterized by being provided with a plate.