JPS62284020A - Charging method for sintering raw material - Google Patents

Abstract

PURPOSE:To control the charging density of the sintering raw material on a pallet so as to improve air permeability and to improve the productivity of sintered ore by using a raw material charger disposed with plural bar materials each having a specific shape at the time of supplying the sintering raw material onto the rotary pallet of a sintering machine for iron ore. CONSTITUTION:The sintering raw material 4 such as powdery iron ore, coke and quicklime is discharged from a hopper 1 onto the rotary pallet 9 of the sintering machine by a drum feeder 2. The raw material charger inclined near to the surface of the pallet 9 is mounted to the lower part of an inclined sloping plate 3 on which the sintering raw material 4 falls. The charger is mounted with the plural bar materials 7 so as to have the smaller width on the entry side of the pallet 9 than on the deliver side and to have the wider spacing from the lower part toward the upper part. The raw material, passing the charger, forms layers on the pallet 9 in such a manner that the coarse grains in the raw material come to the lower side and the pulverized powder comes to the upper side. The densities of the raw material layers 8 are smaller from the upper part toward the lower part and since the air permeation rate from the upper part is not hindered, the sintered ore having the excellent strength is efficiently produced at a high speed.

Description

Detailed Description of the Invention 3. Detailed Description of the Invention (Field of Industrial Application) The present invention is directed to the production of sintered ore to be charged to a blast furnace in the steel industry. This concerns the charging method.

(Prior art) In the conventional sintering method, iron ore powder of approximately 10-10 mm or less is mixed with coke of an appropriate particle size and, if necessary, limestone powder, and the mixture is charged into a sintering pallet and the coke in the light layer is mixed. The coke is ignited, the coke is combusted while sucking air downward, and the combustion heat sinteres the fine ore. As described above, since sintering progresses through the combustion of coke, the supply of air to the sintered layer, that is, the degree of aeration of the sintered layer, is a very important operational factor.

Up until now, measures to ventilate the sintered layer have generally been made by improving the granulation conditions by increasing the size of the granulator, extending the granulation time, and adding bangu such as quicklime to prevent agglomerated particles after humidity control granulation. A method has been implemented in which the raw material after humidity control granulation is coarsened (hereinafter referred to as pseudo particles).

In normal downward draft sintering, if coke is uniformly distributed in the height direction of the sintered layer, the temperature will increase as the temperature goes down due to the characteristics of heat movement within the sintered layer, and the ventilation resistance will increase.

As a method to prevent such drawbacks, for example, Japanese Patent Laid-Open No. 48
Japanese Patent No. 48303 proposes a method in which high-pressure gas is sprayed from a drum ladder to a gas jet provided at the bottom of the drum ladder when pseudo particles are dropped into a sintering pallet. In this method, compressed gas is injected in the forward direction of the pallet, and coke or fine ore with a low specific gravity is deposited on the upper part of the sintered layer, and the lower layer contains less coke and more coarse ore. This is aimed at making the sinterability of the upper and lower layers uniform by lowering the level and completely improving the air permeability during sintering.

In this way, until now, the methods of charging raw materials for sintering (7) have been either to coarsen the raw materials for charging or to devise a charging method for the raw materials to be charged. .

Among these conventional methods, the quicklime addition granulation method has been adopted as a countermeasure against ventilation because of its remarkable effect.

However, when quicklime is added, the cost increases because the price of quicklime is not necessarily cheap, and an alternative technology to adding quicklime is currently desperately needed from the viewpoint of reducing production costs.

1? c. The gas injection method described above is a method of blowing upward obliquely, and when the injection pressure of V% gas is increased, fine particles are blown away.
This is because it is difficult to increase the injection pressure.

There is not necessarily a perfect solution, and a charging method that segregates the grain size of the upper and lower layers and segregates the amount of coke is desperately needed.

(Problems to be Solved by the Invention) The purpose of the present invention is to solve the above-mentioned conventional problems.
When charging the sintering raw material, there is a charging method that controls the charging density of the pseudo particle packed bed charged into the pallet. The object of the present invention is to provide a segregation charging method that allows a large amount of coarse grain raw material to be blended into the raw material.

(Means and actions for solving problems) Non-invention is
Between the sintering raw material supply feeder and the pallet, a plurality of strips whose horizontal width decreases from one end to the other are arranged in parallel or with a partial step at an angle in the longitudinal direction. After receiving the sintered raw material falling from the feeder with a strip, the raw material is dropped onto the pallet from the gap between the strips, so that the sintered layer after being loaded onto the pallet has a low density, with fine grains in the upper layer and fine grains in the lower layer. The feature is that coarse grains can be charged segregated.

That is, D in which the sintering raw material is charged onto the sintering pallet.
In the raw material charging method for the L sintering machine, a plurality of strips are fed out above the sintering pallet, the horizontal width of which gradually decreases from one end to the other. The strips are arranged parallel to each other at intervals so that the narrow ends become pallet entry points 1, and the wide ends of the strips are tilted to a high position and the narrow ends to a low position. This is a charging method in which the sintering material is placed through the strip to form a sintered packed layer.

-Again. The wide end of the strip is tilted at a high position and the narrow end is tilted at a low position, and at both or either of the wide end and the narrow end.

Arrange them in parallel with a step at least in part of them.

This charging method involves charging the sintering raw material through this strip to form a sintered packed layer.

The present inventors were conducting research on improving the air permeability of pseudo particles, and found that air permeability is determined by the initial filling condition of the pseudo particle packed layer of the pallet before the start of sintering, that is, before ignition.
It was discovered that the filling condition was determined by the falling energy of the pseudo particles at the time of charging.

In other words, by controlling the charging density, pseudo-particles without added quicklime can have the same effect on the sintering rate as pseudo-particles with added quicklime.

It turns out that it can be obtained.

For this reason, the present inventors controlled the falling energy when charging the pseudoparticles.

It was found that the charging density can be controlled.

The present invention is based on this knowledge and the known fact that by charging fine-grain raw materials into the upper layer of the sintered layer and coarse-grain raw materials into the lower layer, the upper and lower layers can be fired uniformly. It was completed based on these.

That is, in the present invention, by providing a plurality of strips above the pallet that extend parallel to the clockwise movement of the pallet, the strips receive the raw material that has fallen from the feeder, reduce the energy of the fall, and then return it to the pallet. Since it can be charged, the charging density can be reduced to U'.

In the present invention, the sintered layer after charging the pallet has a low density, and segregated charging is performed in which fine grains are charged in the upper layer and coarse grains are charged in the lower layer.The specific charging method will be described next. state

In the present invention, by using a plurality of □ strips whose horizontal width decreases from one end to the other, the wide part is made wide on the pallet delivery side and narrow on the pallet entry side. Since the gap between the L strips is narrow and the gap between the strips is wide in the narrow part, as the pallet moves, the segregation distribution of fine grains in the upper layer and coarse grains in the lower layer becomes easy, and the wide end part is placed in a high position. .

By placing the narrow end at a low position, it is easier for the raw material to slide down, so after the supplied raw material falls onto the strip,
Most of the fine grains fall directly below the gap between the strips, and the coarse particles move through the gaps between the strips and move toward the narrower width of the strips, that is, the direction where the gaps between the strips are wider (pallet entry side). Fall while moving. the result.

An ideal packed bed can be obtained in which the sintered layer after charging the pallet has a low density, with fine grains segregated in the upper layer and coarse grains segregated in the lower layer.

Furthermore, in the present invention, by arranging the strips as described above and providing a step when arranging the five strips, the transfer of raw materials is promoted or a flow path for the raw materials is formed, so that segregation charging is promoted. be done. There are three methods for providing steps on strips: The method is as follows: (1) The wide end is tilted to a high position, and the narrow end is tilted to a low position, and at least a part of the wide end is provided with a step (2) The wide end is tilted to a high position. (3) The narrow end is tilted to a low position and a step is provided at least in part only at the narrow end (3) The wide end is tilted to a high position and the narrow end is tilted to a low position; At least a portion of both the wide end portion and the narrow end portion is provided with a step.

(Example) Embodiments of the present invention will be described below based on one drawing.

FIG. 1 is a schematic side sectional view of a sintering machine charging section showing a first embodiment of the invention, and shows a sloping plate installed below a three-drum feeder 2. FIG.

A sintered raw material 4 stored in a hopper 1 is cut out from a drum feeder 2, falls through a sloping plate 3, and is charged into a pallet 9 via an inclined strip 7. In this case, the conventional method is used.

Since the raw material is directly dropped and charged from the sloping plate 3 onto the pallet 9, this has been a factor in increasing the charging density. Note that 8 is a sintered layer and 10 is a wind box.

FIG. 2 is a plan view of the strip 7 illustrated in FIG. 1. The upper mounting plate 5 has a width of 1511 IIm, the lower mounting plate 6 has a width of 3
A plurality of sieve strips 7 were attached so that their longitudinal center lines were parallel. That is, the width of the strips 7 on the pallet delivery side is 15 m, and the width on the pallet entry side is 3 mm, and the gap between each strip 7 is 5 mm on the pallet delivery side and 17 mm on the pallet entry side.
It was a simple size.

In this way, the raw material 4 is charged onto the pallet 9 while rolling and falling on the strip 7.

Are the width dimensions of the strips 7 and the gap dimensions between the strips 7 in the first strip mounting portions 5 and 6 limited to the dimensions of this embodiment? However, it can be installed arbitrarily depending on the degree of falling energy, stickiness, rolling friction resistance, etc. of the raw material 4.

In addition, since one strip 7 is inclined so that the entrance side of the pallet 9 is at a lower level, coarse particles in the raw material move toward the pallet entrance side, and the closer the interval between the strips 7 to the bottom of the pallet 9, the more coarse particles in the raw material will move toward the pallet entrance side. Because of the large size, the raw material l#+4 is charged with coarse grains near the bottom of the pallet 9 in #1 and fine grains in #t above.

In this way, according to this embodiment, the falling energy of the raw material is alleviated by the strip material 7, low-density charging is performed, and the segregation of fine grains in the upper layer and coarse grains in the lower layer results in ideal packing. A sintered layer 8 is obtained.

FIG. 3 shows how to connect the strips 7 and the lower mounting plate 6 in Example-2, and the shape of the strips 7 and the gap between the strips 7 on the plane are similar to those in Example-1. 2, but the connection of the strip 7 to the lower mounting plate 6 is shown in the third figure.
As shown in the figure, the feature is that there are 5 bait steps. The installation method is to provide regularity to the arrangement of the single strip members 7 in three stages. As a result, the gap between the strips 7 on the pallet entry side becomes wider than in Example-1, and the raw material 4 is charged into the pallet 9 while shifting and falling on the strips 7.

Since the five strips 7 are inclined so that the entrance side of the pallet 9 is at a lower level, coarse particles in the raw materials move toward the entrance side of the pallet 9, and the intervals between the strips 7 are lowered to the bottom of the pallet 9. The closer the grains are, the larger the grains become, so near the bottom of the pallet 9 there are coarse particles,
The upper layer is charged with fine-grained raw materials.

In this way, according to Example-2, the falling energy of the raw material 4 is alleviated by the single strip material 7, and low-density charging is performed.
In addition, fine grains are charged in the upper layer and coarse grains are charged in the lower layer, so that an ideally packed sintered layer 8 is obtained, and the controllability of segregation becomes easier.

In this embodiment, a step is provided only at the attachment of the narrow width portion of the single strip 7, but by providing a step only at the attachment of the wide portion of the single strip 7, the gap on the noselet delivery side can be controlled by the step. Furthermore, steps may be provided on both the wide and narrow portions of the strip 7.

Note that the number of steps and the step dimensions of the strips 7 at the one-strip mounting portion are not determined by this example; if the gaps between the strips are made larger on the pallet entry side, the degree of segregation will change. It can be set arbitrarily depending on the situation.

Next, the results of Examples 1 and 2 will be explained.

(a) Figure 4 shows the charging density of sintered ore raw materials.

From the results shown in Figure 4, it can be seen that in the conventional method, the charging density of pseudo particles without adding quicklime is 1.93 t/m', and the charging density of pseudo particles whose granulation is strengthened by adding quicklime is 1- 861/
Although there is a difference in W/, according to the present invention, Example-1 is 1.89 t/- even with raw materials without added quicklime.

In Example-2, a charging density of x, 87 t/-, which is equivalent to that of the conventional pseudo particles added with quicklime, can be obtained.

1. Figure 5 shows the degree of segregation of pseudoparticles from the upper layer to the lower layer. Example of the present invention compared to the conventional method
Both Nos. 1 and 2 are segregated charging in which fine grains are distributed in the upper layer and coarse grains are distributed in the lower layer.

(b) Figure 6 shows the productivity of sintered ore. As can be seen from the results in Figure 6, the productivity of the raw material without added quicklime is 27.0 t/D/ml using the conventional method, but according to the non-inventive method, the productivity of Example-1 is 31.3 t/D/ml. vd, Example-2
is 32.1 t/D/-, which is equivalent to the productivity of 33.2 t/D/- of the raw material added with quicklime in the conventional method.

As described above, since the charging density is low and the charging is segregated, the permeability of the packed bed is improved, the sintering speed is increased, and the productivity is improved.

Incidentally, the attachment of the upper and/or lower strips 7 to the plate 5.6 is not limited to this embodiment-2; for example, the method shown in Fig. 7 (
, ) to (f) are also possible. It is also effective to install a certain seven-turn type at two or more levels.

- Figures 8 (a) to (f) show the shape Dk of each ridge of the strip 7, and the strip 7 is not limited to round bars.
) f (C) It may be a square material as shown in (d), or it may be made of a single double vibrator with a bearing 11 as an m-rolling body as shown in the same figure (e). Alternatively, it is also possible to use the bar as a pipe 12 and to ventilate the air through the pipe 12 as shown in FIG. 2(f).

It is also effective to connect the mounting portion of the strip 7 with tension by connecting it with a spring, or to prevent dFV by using a piperator mechanism. Further, in Example 1, the material is charged from the sloping plate 3, but it is also possible to directly charge from the drum feeder via the strip material without the sloping plate.

(Effects of the Invention) As explained above, the present invention provides a plurality of strips whose horizontal width decreases from one end to the other end above the sintered pallet, with the wide end facing toward the pallet delivery side. In addition, the strips are arranged in parallel at intervals so that the narrow ends are on the pallet entry side, and the wide ends of the strips are tilted to a high position and the narrow ends to a low position. The sintered material is charged through the strips, and the sintered material falls into the pallet while transferring over the strips, so the falling energy is alleviated by the strips. The charging density becomes smaller and the charging becomes segregated, with fine grains in the upper layer and coarse grains in the lower layer. Therefore, the air permeability of the sintered layer increases, the sintering speed increases, and productivity increases. Furthermore, there is no need to add quicklime as a binder, and the product yield V of the sintered ore can be improved, resulting in significant effects such as cost reduction.

[Brief explanation of drawings]

FIG. 1 is a schematic cross-sectional view of I11 showing Example-1 of the present invention;
Figure 2 is a plan view showing the arrangement of strips, Figure 3 is Example-2
A drawing showing how to assemble strips. Figure 4 is a diagram showing the effect of improving charging density, Figure 5 is a diagram showing the particle size segregation effect, Figure 6 is a diagram showing the same effect on productivity, and Figure 7 is a diagram showing the effect of improving productivity.
Figures (a) to (f) are drawings showing how to assemble other embodiments of the strip, and Figures 8 (, 1 to (f) are drawings showing other embodiments of the strip. 1. ...Hopper, 2...Drum filter% 3.
...Sloping plate% 4...Sintering raw material, 5.
... Strip upper mounting plate, 6... Strip lower mounting plate, 7...
- Strip material, 8... Sintered layer, 9... Pallet, 10...
・Wind box. 11...Bearing, 12...Pipe. Agent Patent attorney Masaaki Akizawa Mitsunobu 1 famous person

Claims (1)

[Claims] 1. In a raw material charging method for a DL sintering machine in which a sintering raw material is charged onto a sintering pallet, the horizontal width of the upper part of the sintering pallet decreases from one end to the other end. The wide ends of the strips are placed on the pallet delivery side.
In addition, the strips are arranged in parallel at intervals so that the narrow ends are on the pallet entry side, and the wide ends of the strips are arranged in a high position and the narrow ends are inclined in a low position. A method for charging sintering raw materials, characterized in that the sintering raw materials are charged through the strips to form a sintered packed layer. 2 The wide ends of the strips are inclined to a high position and the narrow ends to a low position, and both or either of the wide ends and narrow ends are arranged with a step at least partially. Claim 1 characterized in that
Charging method described in section.