JPH01284374A - Classifying device - Google Patents

Abstract

PURPOSE:To classify a large volume of raw materials with the simple device by disposing a segmenting means into the locus drawn by falling raw materials by the tail part of a belt conveyor and segmenting large lumps to an outer side and small lamps to an inner side with the segmenting means as a boundary. CONSTITUTION:A beater cleaner 4 is provided to the rear surface of the belt conveyor 1 and the conveyor 1 is oscillated. The raw materials 5 on the conveyor 1 are so segmented by the oscillation that the large lumps are brought to the upper side and the small lumps to the lower side. The pawl-shaped segmenting plate 2 having a parabolic shape and a sharp pointed tip is disposed in the falling locus drawn by the raw materials 5 falling from the tail part of the conveyor 1 and is moved horizontally forward and backward within the raw material locus by a power cylinder 3 supported horizontally movably forward and backward to and from the conveyor 1. The raw materials are thereby easily segmented to the large lumps falling parabolically from the conveyor 1 and the small lumps falling straightforward as they are.

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a classification device for sintered ore, lump ore, coke, etc. (hereinafter referred to as raw materials), which are raw materials for blast furnaces in the steel industry.
More specifically, the present invention relates to a classification device that separates raw materials into large lumps and small lumps below the tail of a belt conveyor in order to easily classify the raw materials transported by a belt conveyor during the conveyance process.

Since a conventional blast furnace is a countercurrent reaction device in which raw materials are charged from the top and gas is blown in from the bottom, it is very important to ensure ventilation within the furnace. For this purpose, the raw materials charged into the blast furnace are
The small particles generated during the transportation process before the furnace are classified and removed so that they have a particle size larger than the above. Conventionally, most of these classifications have been carried out by sieving, which increases equipment costs, and the classification point changes due to wear of the sieve screens used, making maintenance and management of the classification difficult.

If the sieve screen becomes severely worn, it will have to be replaced, which increases maintenance costs and requires temporary suspension of operation for replacement.

As described above, in order to maintain the stable operation of a blast furnace, the particle size of the raw material used as the charge has conventionally been maintained and controlled using equipment that requires a great deal of labor and investment.

Problems to be Solved by the Invention As described above, the classification method using sieving requires a large amount of equipment cost and is extremely difficult to maintain and manage.

Moreover, the size of the sieve screen must be changed depending on the desired particle size, and as the number of raw materials to be classified increases, the sieving efficiency decreases, so the amount must be kept below a certain level. In this case, it would be necessary to install equipment to separate multiple sieves. This required a large amount of space and a large amount of equipment costs, which was one of the causes of rising iron manufacturing costs.

The object of the present invention is to obtain an apparatus that is easy to maintain and can classify raw materials at low cost, and further to enable classification of desired particle size using the apparatus.

Solution to the Problem It is well known that when kinetic energy such as vibration is applied to a raw material having a particle size distribution, so-called segregation occurs, with large lumps gathering at the top and small lumps at the bottom. We focused on the fact that raw materials are transported to the blast furnace through numerous belt conveyors, and particle size segregation has already occurred on the belt conveyors, and we considered using this to classify the raw materials. As a result of extensive research, we found that it is possible to easily and efficiently separate raw materials by placing a sorting means within the falling trajectory of the raw materials below the tail of the belt conveyor, and separating large lumps on the outside and small lumps on the inside. The present invention was completed based on the discovery that it is possible to classify

Therefore, the present invention is characterized in that a sorting means is arranged within the trajectory drawn by the raw material falling from the tail portion of the belt conveyor, and using this as a boundary, large lumps are separated into the outside and small lumps are separated into the inside. be.

Here, as a means for dividing, a preferable example is a plate oriented vertically or slightly inclined, preferably with a sharpened upper end, and an even more preferable example is a plate whose outer side follows the falling locus of the large lump. In particular, there are those with a nail-shaped cross section whose inner and outer sides are parabolic along the falling locus of large lumps and small lumps. The 0 category is preferably set to move the means forward and backward, and the position i11! This is because by adjusting the particle size, classification can be performed at a desired particle size. This was also supported by the results of numerous experiments conducted by the present inventors.

The invention is therefore also characterized in that the section allows the means to be adjusted in position.

As mentioned above, the raw materials transported by the belt conveyor undergo particle size segregation on the belt conveyor, but it is desirable to vibrate the belt conveyor to strengthen the segregation, and it is also possible to adjust the amount and amplitude of vibration. It is more desirable to do so, as this allows the accuracy of classification to be adjusted.

Effect The smaller the particle size of the small-sized raw materials in the lower layer of the belt conveyor, the more they naturally fall straight down from the tail of the belt conveyor, whereas the large-sized raw materials in the upper layer fall in a parabolic shape from the outside due to the action of inertia. Draw a trajectory and fall. Therefore, by placing a means at an appropriate position in the middle, it is divided into an inner small mass and an outer large mass.

The partition means is plate-shaped and has a sharp tip, and furthermore, the outside, especially the inside and outside, are shaped so that they follow the falling trajectory of the raw material, so that the flow of the raw material becomes smooth.

In addition, by adjusting the position of the means, it is possible to classify the particles according to the desired particle size, and the amount of vibration of the belt conveyor can be adjusted to iF! The classification accuracy can be changed by adjusting the

Embodiment m The rack W is placed within the falling locus of the raw material falling from the tail part of the belt conveyor I, and the claw-shaped section with a sharp tip whose inner and outer sides are parabolic is called the plate 2, and the section is called the plate 2. It consists of a power cylinder 3 that supports the belt conveyor 1 so that it can move forward and backward horizontally.The plate 2 is made of abrasion-resistant ceramic irradiated, and the bottom surface of the belt conveyor 1 is made of A beak cleaner 4 is provided to vibrate the conveyor l.

Using the above-mentioned classification device, the coke 5 was sorted by the power cylinder 3 by changing the position of the plate 2 and transferred to the belt conveyor (particle size 25 to 100 mm before conveyance).
were classified at point A and point B, respectively. Figure 2 shows the particle size distribution of coke divided into right and left sides. As shown in the figure, there is a clear difference in particle size between the right and left sides at both points A and B, indicating that they are classified. I found out that there is. By utilizing this, we were able to obtain the effects shown below.

As the ventilation inside the blast furnace deteriorated significantly, the amount of air blown decreased, and the pig iron tap ratio decreased to 1.5. Therefore, in order to improve the air permeability in the blast furnace, the coke was classified at point B, and the obtained coke with many large lumps of the particle size shown on the right was selectively charged into the blast furnace. As a result, the permeability of the blast furnace was improved, and the pig iron production ratio was able to be restored to the normal level of 2.0.

Furthermore, when sorting at point A in front of the blast furnace, most of the coke on the left side has a size of 251 or less, and most of the coke on the right side has a size of 251 or more. When the coke on the right was classified at point A and charged into the blast furnace, there was almost no difference in the air permeability of the blast furnace compared to the conventional method in which fine powder was removed by sieving in front of the furnace.

Example 2 As shown in Fig. 3, using the same classification device as in Example 1 and under the same conditions as in Example 1, the sintered ore 6 was classified by changing the temporary position 2 to point A and point B, respectively. Classification was performed at the position.

The particle size distribution of each sintered ore divided into the right side and the left side is
At any position of point A or B from figure 0 shown in the figure,
The grain sizes on the right and left sides are clearly different, indicating that sintered ore can also be classified.

Using these facts, we were able to confirm the effects shown below.

Due to the marked deterioration of air permeability, the amount of air blown was reduced and the iron production ratio was reduced to 1.8.In order to improve air permeability, the sintered ore was classified at point B. Sintered ore with many lumps was selectively charged into the blast furnace. As a result, the permeability of the blast furnace was improved, and the iron production ratio was able to recover to 2.1.

Also, when classifying at point A in front of the blast furnace, there are 25
Most of the sizes are ts or smaller, and most of the ones on the right are 25
Since it was larger than f1, it was classified at point A in front of the blast furnace, and when the sintered ore on the right was charged into the blast furnace, it was sieved in front of the furnace to remove fine powder as in the conventional method. Compared to the time, there was almost no significant difference in the ventilation of blast furnaces.

Effects of the Invention The present invention is configured as described above, and has the following effects.

The classification device according to claim 1 is such that the classification means is simply arranged within the fall trajectory of the raw material at the tail portion of the belt conveyor to classify the raw material into large lumps and small lumps. Compared to sieving equipment, a relatively large amount of raw materials can be classified using compact equipment, and since no sieving screen is used, maintenance of the classification equipment is extremely easy, and as a result, classification costs are reduced. The manufacturing cost of iron can be reduced.

According to the classification device of the second aspect, the raw materials falling from the tail portion of the belt conveyor can be smoothly sorted.

In the classification apparatus according to claim 3, classification can be performed at a desired particle size by adjusting the position of the means.

According to the classification device of the fourth aspect, the particle size segregation of the raw material on the belt conveyor can be strengthened.

[Brief explanation of the drawing]

Figure 1 is a schematic diagram of the classification device, Figure 2 is a graph showing the cumulative passage rate of coke classified by the same device, Figure 3 is a schematic diagram of the separating device, and Figure 4 is a graph showing the cumulative passage rate of coke classified by the same device. It is a graph showing the cumulative passage rate of sintered ore. 1. Belt conveyor 2. Classification IT Plate 3. Power cylinder 4. Beater cleaner Applicant Nissin Steel Co., Ltd. agent Patent attorney Akira Sato - Moan wo Sode g! Seagull umbrella-like C)

Claims (4)

[Claims] (1) A classification device characterized in that a sorting means is arranged within the trajectory of the raw material falling from the tail portion of a belt conveyor, and this is used as a boundary to sort large lumps on the outside and small lumps on the inside. (2) The classification device according to claim 1, wherein the separating means has a sharp tip and a shape that follows the falling trajectory of the raw material. (3) The classification device according to claim 1, wherein the sorting means moves horizontally toward the belt conveyor and is adjustable in position. (4) The classification device according to claim 1, wherein the belt conveyor is provided with a vibration device.