JPH046776B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a method for distributing a predetermined amount of sintered raw material onto a pallet from the sintered raw material when a large amount of sintered raw material is sent to the pallet, especially at the beginning of charging. The present invention relates to a method for charging sintering raw materials that smoothly performs the work of forming a raw material layer.

[Conventional technology]

In the method of manufacturing sintered ore from ironmaking raw materials such as fine ore, iron ore powder of approximately 10 mm or less is mixed with coke of an appropriate particle size and limestone powder as necessary, and this mixture is supplied to a sintering pallet. ing.
Then, the coke on the surface of the supplied sintering raw material is ignited, the coke is combusted while sucking air downward, and the combustion heat generated at this time sinteres the fine ore.

Here, when the sintering raw material is distributed with a uniform particle size distribution along the height direction of the raw material layer, due to heat movement inside the raw material layer, the lower part of the raw material layer becomes higher in temperature and the ventilation resistance increases. do. In addition, the surface layer portion is cooled by the drawn outside air, resulting in insufficient temperature rise and incomplete sintering. As a result, the strength of the sintered ore decreases and the sintered ore is pulverized during post-processing such as crushing and sieving, so that the proportion of the sintered ore that is not used as a raw material for blast furnace charging increases.

Therefore, in order to charge the sintering raw material into the pallet of the sintering machine while distributing the sintering raw material with a continuous particle size distribution under stable conditions, we A charging method using a sieve with strips arranged thereon was developed and filed as Japanese Patent Application No. 62-21401, Japanese Patent Application No. 62-85543, etc.

[Problem that the invention seeks to solve]

When using a sieve in which these strips are arranged, it is possible to give a predetermined particle size segregation, dispersion, etc. to the sintering raw material layer formed on the pallet of the sintering machine. Therefore, compared to conventional charging methods, the sintering reaction is made more uniform, making it possible to produce sintered ore at a higher yield.

However, when a large amount of sintered raw material is fed at once, especially at the beginning of charging,
Under normal specifications, the processing capacity of the sieve may be exceeded and the sloped surface of the raw material layer formed on the pallet of the sintering machine may swell. With such excitement,
Not only can the strips forming the sieve become buried in the sintering raw material, but also problems such as equipment damage occur.
Moreover, the classification ability or dispersion ability of the sieve cannot be fully demonstrated. Once the sieve is in this state, it takes time to return to its original normal state, and during that time the sintering raw materials deposited on the pallet must be sintered evenly.
This results in a decrease in sintering yield.

In addition, even if the strips are not buried in the sintered raw material on the pallet, if a large amount of sintered raw material is sent, the classification or dispersion effect will fluctuate, and the sintered raw material will be palletized with a predetermined particle size distribution. It becomes difficult to form on top. In addition, the raised sintered raw material is compacted in the leveling step performed by the subsequent cut plate, reducing the air permeability of the raw material layer. In this case, uniform sintering is hindered and defects such as insufficient sintering or oversintering occur.

Therefore, the present invention solves the problem that occurs when a large amount of sintering raw material is sent by adjusting the condition of the sieve, and creates a raw material layer that can perform a uniform sintering reaction in the sintering machine. The purpose is to form on a pallet.

[Means for solving problems]

In order to achieve the object, the method for charging sintering raw materials of the present invention charges sintering raw materials into pallets of a sintering machine through a sieve made up of a plurality of strips extending along the flow direction of the charged raw materials. When entering the pallet, the height of the slope of the raw material layer formed on the pallet is detected, and when the slope becomes high, the height from the raw material layer to the sieve is increased and/or the sieve is configured. It is characterized by reducing the inclination angle of each strip.

〔Example〕

Hereinafter, the features of the present invention will be specifically explained using examples with reference to the drawings.

FIG. 1 shows an outline of the apparatus used in this example.

The sintered raw material 2 cut out from a container 1 such as a hopper is rolled on the circumferential surface of the drum feeder 3.
It is fed onto a chute 4 which is arranged slanting downward. The sintering raw material 2 flows downward along the inclined surface of the chute 4. A sieve 5 in which a plurality of strips are arranged along the flow direction of the sintering raw material 2 is provided below the chute 4, and the sintering raw material 2 is classified by the sieve 5 and transferred to the pallet 6 of the sintering machine. is supplied to form a raw material layer 7.

When the sintering raw material 2 is sent out from the container 1 in a steady state, a regular inclined surface 7 is formed on the pallet 6 as shown by the solid line, commensurate with the processing capacity of the sieve 5.
It is filled as a raw material layer 7 having a. However, if the supply amount of sintering raw material 2 becomes temporarily excessive,
Excess sintering raw material 2 accumulates on the pallet 6, forming a raised inclined surface 7b as shown by the dotted line. When such an inclined surface 7b is formed, the particle size distribution of the raw material layer 7 is greatly disrupted, and the classification ability or dispersion ability of the sieve 5 cannot be fully demonstrated. Furthermore, in an extreme case, the strips constituting the sieve 5 may become buried in the raised inclined surface 7b, causing damage to the apparatus.

Therefore, in this embodiment, a plurality of electrode rods 8 are arranged to face the inclined surface 7a of the raw material layer 7. These electrode rods 8 are electrically connected to each other through air having a low dielectric constant in normal times. However, as described above, when the sintering raw material bulges and forms the inclined surface 7b, the mutual electrode rods 8 buried in the sintering raw material are connected through powdered ore having a low dielectric constant. That is, whether the raw material layer 7 has a regular slope 7a or a raised slope 7b is detected as a change in dielectric constant.

On the other hand, the sieve 5 is supported at its proximal end by an operating section 10 movably disposed on a pedestal 9. This operating section 10 is connected to a hoist 12 via a traction rope 11.
2, it moves back and forth on the pedestal 9. Also,
The slope state of the raw material layer 7 detected by the electrode rod 8 is input to the hoist 12 as a detection signal 13.

As a result, the electrode rod 8 detects that the end of the raw material layer 7 has become a raised slope 7b, and the hoist 12 is driven based on the detection signal 13. As a result, the tow rope 11 is wound up,
The operating unit 10 moves on the pedestal 9 in the right direction in FIG. At this time, the distance between adjacent strips constituting the sieve 5 increases from the base end to the tip end. Therefore, the sintering raw material 2 falling from the lower end of the chute 4
The material passes between the strips having a large distance between adjacent strips and falls onto the slope of the pallet 6 or the raw material layer 7. Therefore, since a large amount of sintering raw material 2 passes through the sieve 5, the raised inclined surface 7b can be eliminated in a short time. Further, since the sieve 5 is moved backward, the strip can be released from the state buried in the inclined surface 7b.

Then, when the raised inclined surface 7b disappears, the dielectric constant detected by the electrode rod 8 decreases. By the detection signal 13 representing this result, the hoist 1
2 is reversed to advance the sieve 5. Thereafter, while forming a raw material layer 7 having a regular inclined surface 7a on the pallet 6, the sintered raw material 2 is sintered in a normal state.
Charging continues.

In the above example, the slope state of the raw material layer 7 was detected by the electrode rod 8, and the sieve 5 was moved forward or backward according to the detected value. However, the present invention is not limited to this. For example, instead of the electrode rod 8,
An ultrasonic level meter or the like can be used as a slope state detection means. Furthermore, instead of moving the sieve 5 back and forth, it is also possible to change the inclination angle of the strips that make up the sieve 5.

As an example, FIG. 2 shows an example in which the slope state of the raw material layer is detected using an ultrasonic level meter, and the inclination angle of the strips constituting the sieve with respect to the horizontal plane is changed based on the detected value.

In this example, the slope state of the raw material layer 7 is detected by an ultrasonic level meter 21, and the detected value is inputted to the control circuit 23 as a detection signal 22. A control signal 24 is output from this control circuit 23 to the hydraulic pump 25. This hydraulic pump 25 is arranged between the pedestal 9 on which the operating section 10 is placed and the machine stand 26. Then, based on the control signal 24 corresponding to the slope state of the raw material layer 7, the operating section 1
By tilting the sieve 5, the inclination angle of the sieve 5 is changed. For example, when the slope state of the raw material layer 7 detected by the ultrasonic level meter 21 exceeds a reference value, the hydraulic pump 25 is lowered to reduce the inclination angle of the sieve 5. While charging the sintering raw material in this state, when the slope condition of the raw material layer 7 becomes below the reference value, the hydraulic pump 25 is raised to bring the inclination angle of the sieve 5 to a steady state. .

In this way, when using an ultrasonic level meter as a detection means, it is possible to continuously detect the slope state of the raw material layer, so it is more accurate than in the case of the electrode rod 8 shown in Fig. 1. Detection results are obtained, and the slope state can be controlled with high precision.

In this way, the raised inclined surface 7b can be eliminated within a short time, so that the rate at which the particle size distribution of the raw material layer 7 formed on the pallet 6 deviates from the predetermined pattern can be reduced. can. As a result, the sintered raw material 2 could be made into sintered ore with a good yield. For example, when the raw material layer 7 formed using the apparatus shown in Fig. 1 was sintered while suppressing the raised inclined surface 7b that tends to occur at the beginning of charging, sintered ore was produced with a yield of 77.8%. We were able to. On the other hand, the raised slope 7
When the raw material layer 7 containing b was sintered, the sintering yield was 72.8%.

〔Effect of the invention〕

As explained above, in the present invention, by charging the sintering raw material while always maintaining the end portion of the sintering raw material layer formed on the pallet of the sintering machine in a regular inclined plane, , it becomes possible to fill the pallet with the sintering raw material without significantly disrupting the particle size distribution of the sintering raw material layer over a wide range.
As a result, the sintering reaction can proceed uniformly, and the product yield of sintered ore is improved.

[Brief explanation of drawings]

FIG. 1 illustrates a first embodiment of the present invention, and FIG. 2 similarly illustrates a second embodiment.

Claims (1)

[Claims] 1. When charging the sintering raw material to the pallet of the sintering machine through a sieve consisting of a plurality of strips extending along the flow direction of the charged raw material, the height of the slope of the raw material layer formed on the pallet is A sintered raw material characterized in that when the slope becomes high, the height from the raw material layer to the sieve is increased and/or the inclination angle of each strip forming the sieve is decreased. How to charge.