JPH0421724A - Device for charging raw material to sintering machine - Google Patents

Abstract

PURPOSE:To improve the grain size segregation and carbon segregation in the layer height direction of the sintering raw materials charged to a pallet by curving a chute at a specified radius of curvature in such a manner that the front surface of the chute is recessed at the time of supplying the sintering raw materials via the chute into the pallet. CONSTITUTION:The sintering raw materials 6 in a servo hopper 1 are fed out by a roll feeder 2 and are supplied via the chute 11 into the pallet 4 to form the sintering raw material layer 7. The pallet is moved by a motor-operated endless grade 5 and the sintering raw materials are ignited in an ignition furnace 9. The fires are sucked downward in an air box 8, by which the sintering raw material layer 7 is sintered. The front surface of the chute 11 on which the sintering raw materials 4 glide is recessed to the specified radius of curvature or is curved to a spiral type of the radius of curvature increasing in proportion to the 0 to 1 powers (not inclusive of 0 and 1 powers) in the position perpendicular to the chute 11. The moving speed in the horizontal direction of the sintering raw materials 6 at the bottom end of the chute is increased in this way, by which the grain size segregation and carbon segregation in the layer height direction are improved.

Description

Detailed Description of the Invention ``Object of the Invention'' The present invention relates to a device for charging raw materials into a sintering machine, which improves particle size segregation and carbon segregation of raw materials charged into pallets, etc.
The present invention aims to improve the production yield and productivity of sintered ore and provide an apparatus with excellent maintainability.

(Industrial application field) Device for charging sintering raw materials into pallets in endless moving grade sintering machines, etc.

(Prior art) In order to charge sintering raw materials into a pallet in an endless moving grade sintering machine, as shown in FIG. It is cut by the rotation of the roll feeder 2 installed at the lower end, and discharged onto the chute 3 whose upper end is located directly below the roll feeder 2 and whose lower end is located above the pallet 4 and is inclined at a predetermined angle. This is carried out by supplying the liquid through bullet 3 and into bullet 4.

In this way, the sintering raw material 6 charged into the pallet 4
is passed through the ignition zone and the sintering zone sequentially by the endless moving grade 5, and in the ignition zone, the coke powder on the surface of the sintered raw material is ignited by the ignition furnace 9. High-temperature combustion exhaust gas generated by combustion of coke breeze is sucked downward by a wind box 8 provided below the pallet 4, heats the sintering raw material layer 7 in the pallet 4, and heats the sintering material layer 7 inside the pallet 4. This is baked in In this way, the sintered raw material in the pallet 4 is sintered and discharged from the downstream end of the endless moving grate 5 as sintered ore.

In the production of the above-mentioned sintered ore, the upper layer of the sintered raw material layer 7 in the pallet 4 generally lacks heat;
As a result of excessive heat in the lower layer, the production yield of sintered ore decreases. In order to solve this heat deficiency in the upper layer of the sintering raw material layer 7, it is necessary to mix a larger amount of coke powder into the sintering raw material 6 than necessary, which increases the production cost. As the sintered ore increases, the quality of the sintered ore varies. In order to solve such problems, many studies have been carried out in the past, and for example, the following methods have been announced.

■Flat chute charging method A method in which the height, length, and angle of inclination of the chute are set to optimal values in order to adjust the grain size segregation of the sintered raw materials in the layer height direction within the pallet.

■Two-stage charging method A method in which the sintering raw materials are charged into the pallet in two stages: the upper layer and the lower layer, and the charging method is such that there is more coke powder in the upper layer than in the lower layer.

■ Horizontal tensioning method of wires or rods A screen is installed in the middle of the chute, on which a large number of wires or rods are stretched at predetermined intervals, perpendicular to the flow direction of the sintered raw material sliding down the chute. A method in which sintered raw materials with large grain sizes cut out by a roll feeder and slid down on a screen are fed to the lower part of the pallet, and sintered raw materials with small grain sizes that pass through a screen are fed to the upper part of the pallet.

■Rondo vertical tension system On the downstream side of the chute, there are a number of openings and 7 holes at predetermined intervals parallel to the flow of the sintered raw material sliding down the chute, and the lower ends of the chute are arranged at different levels in the height direction. The sintered raw material, which is cut out by a roll feeder and slides down on the rod, with a large particle size is supplied to the lower part of the pallet, and the sintered raw material with a small particle size, which passes through the rod, is supplied to the upper part of the pallet. method to do.

(Problem B to be solved by the invention) Although the conventional techniques described above have certain merits, they still have the following problems:
It cannot be considered desirable.

In other words, the above-mentioned flat plate chute charging method has not been able to sufficiently solve the above-mentioned problems, and furthermore, the particle size distribution of the granulated pseudo-particles at each position within the pallet varies widely, As a result, there is a problem with the air permeability of the sintered layer.

According to the above two-stage charging method, the carbon segregation as a whole layer is improved, but the carbon segregation becomes discontinuous, and particle size segregation and variation in particle size distribution are hardly improved. This requires equipment for access, which increases costs.

The wire or 7-wire horizontal tensioning method described in (2) above improves grain size segregation and carbon segregation, but as in (2) above,
Particle size segregation and carbon segregation become discontinuous, and the variation in particle size distribution is not improved much. Moreover, in the middle of the chute, there are many wires or rods that are perpendicular to the flow of the sintering raw material sliding down the chute. Since the wire or rod is stretched, the sintering raw material adheres to the wire or rod significantly, making it impossible to use the wire or rod continuously for a long period of time. In this case, if a scraper is installed and operated intermittently to scrape off the sintering raw material adhering to the wire or opening, the problem of adhesion can be solved; Since the input state is disturbed, the above-mentioned effect is reduced.

According to the above-mentioned vertical rod tensioning method (2), grain size segregation, variation in particle distribution, and carbon segregation are improved, but the sintering raw material adheres to the rod so much that it cannot be used continuously for a long period of time. In this method, if each rod is rotated about its axis, the adhesion of the sintering raw material to the rods can be reduced, but the mechanism for this is complicated and maintenance problems remain.

The present invention solves the problems in the prior art described above, that is, improves particle size segregation and carbon segregation in the layer height direction of the sintering raw material charged in a pallet, homogenizes the thermal history, and performs sintering. It is possible to improve the productivity of sintered ore by improving the production yield of sintered ore and also by improving the variation in the particle size distribution of granulated pseudoparticles at each position within the bullet. The object of the present invention is to provide a device for charging raw materials into a sintering machine that has less adhesion and is easy to maintain.

"Structure of the Invention" (Means for Solving the Problems) This invention provides a method for cutting out the sintered raw material contained in the hopper from the hopper and supplying it to a continuously moving bullet. In a raw material charging device for a sintering machine consisting of a chute with its lower end located directly below the hopper and above the barrel throat, the radius of curvature is set so that the upper surface on which the sintered raw material slides is concave. is constant, or the radius of curvature is 0 to 1 power of the vertical position of the chute (
This is a material charging device for a sintering machine characterized by being curved as a spiral shape increasing in proportion to (not including 0 and 1st power).

(Function) By increasing the horizontal movement speed of the sintered raw material at the lower end of the chute, particle size segregation and carbon segregation in the layer height direction of the sintered raw material charged into the bullet are improved.

The inventors used a flat plate chute to investigate the effect of the horizontal angle of the chute on the horizontal movement speed of the sintered raw material at the lower end of the chute, and found that when the horizontal angle of the flat plate chute was lowered, , the proportion of the horizontal component of the moving speed increases, but the moving speed itself decreases, so overall the horizontal moving speed of the sintered raw material at the lower end of the chute decreases, and the horizontal angle of the flat chute When increasing, the movement speed itself increases, but the horizontal component ratio of the movement speed decreases, so the horizontal movement speed of the sintered raw material at the lower end of the chute decreases as a whole, and In this case, the vertical movement speed of the sintered raw material at the lower end of the chute increases, which reduces the porosity of the sintered raw material layer charged into the bullet, increasing the production yield and productivity of the sintered ore. In other words, in the case of a flat chute, we found that there is an optimum value for the angle of the chute relative to the horizontal.

Therefore, with reference to the above study results, the inventors conducted further research on a method for increasing the horizontal movement speed of the sintered raw material at the lower end of the chute. In order to increase the speed itself, it is mainly necessary to increase the horizontal angle of the chute at the position where the sintered raw material cut out from the roll feeder falls into the chute, and to increase the sintering rate at the lower end of the chute. In order to increase the horizontal component proportion of the raw material movement speed,
It was confirmed that it is sufficient to reduce the horizontal angle of the lower end of the chute.

On the other hand, the sintered raw material cut out from the roll feeder significantly adheres to the chute. In other words, in order to prevent the sintering raw material from adhering to the chute and to satisfy the above research results, it is necessary to continuously change the horizontal angle of the top surface of the chute. A shape with a smoothly curved concave top surface is good.

The above study results and the maintainability of the chute (for example, the versatility of the chute material when replacing a worn part of the chute when a part of the chute is worn out)
Considering this, we devised a chute with a constant radius of curvature.

The present inventors also conducted research on a method for further increasing the moving speed of the sintered raw material at the lower end of the chute, and changed the radius of curvature that determines the shape of the upper surface of the chute to zero at the vertical position of the chute. By increasing it in proportion to the first power, the frictional resistance between the sintered raw material sliding down on the upper surface of the chute and the upper surface of the chute is equalized and reduced. In other words, by using a chute whose radius of curvature increases in proportion to the 0 to 1 power of the vertical position of the chute, particle size segregation and carbon segregation can be improved more than a chute whose radius of curvature is constant. possible. Further, since the frictional resistance between the sintered raw material sliding down the upper surface of the chute and the upper surface of the chute is equalized and reduced, adhesion of the sintered raw material to the chute and wear of the chute are significantly reduced. As a result, there is almost no disturbance in the charging condition due to the adhesion of the sintering material to the chute, and the life of the chute material is significantly improved.

Regarding the variation in particle size distribution, both the chute with a constant radius of curvature and the chute with a radius of curvature increased in proportion to the 0 to 1 power of the vertical position of the chute are different from conventional equipment. Compared to conventional equipment, particle size segregation is significantly improved and variation is reduced.

〔Example〕

Specific embodiments of the invention will now be described with reference to the accompanying drawings. FIG. 1 is a schematic side view of a first embodiment of the apparatus according to the invention.

That is, the one shown in FIG.
Between the roll feeder 2 for cutting out the material and the continuously moving pallet 4, there is an inclined chute whose upper end is located directly below the roll feeder 2 and whose lower end is located above the pallet 4. 11 are provided. The top surface of the chute 11 is concavely curved with a constant radius of curvature. The radius of curvature and the center position of the radius of curvature are
the horizontal angle of the chute 11 at the position where the sintered raw material cut out from the roll feeder 2 falls onto the chute 11;
The angle of the lower end of the chute 11 with respect to the horizontal is determined to be optimal.

FIG. 2 is a schematic side view showing a second embodiment of the device of the invention. As shown in FIG. 2, the shape of the upper surface of the chute 21 in this embodiment has a radius of curvature that increases in proportion to the vertical position of the chute 21 from 00 to the 1st power (not including 0 and 1st power). It has a spiral shape and is concavely curved. Center position of the radius of curvature, multiplier in the range of 0 to 1 (
0 and 1 are not included) and the proportionality constant between the radius of curvature and the value obtained by raising the vertical position of the chute 21 to the O-1 power. The horizontal angle of the chute 210 at the falling position and the horizontal angle of the lower end of the chute 21 are
It is determined to be in the optimum state.

The above-mentioned horizontal angle of the chute 11 or 21 at the chute drop position of the sintered raw material and the horizontal angle at the lower end of the chute 11 or 21 vary depending on the type of raw material and the amount of raw material cut out, but are in the optimum state. Some examples of the raw material cut-out amount in relation to the vertical position multiplier of the spirally increasing radius of curvature related to the shape of the top surface of the chute and the degree of grain size segregation described below are as shown in FIG. , preferably 0 to 0.
The ninth power, more preferably the range of 0.2 to 0.8 power (200
When t/h・m is 099th power, 100 t/h −
When m, it becomes 0.8th power).

The present inventors used the charging device of the first embodiment shown in FIG. 1 and the charging device of the second embodiment of the present invention shown in FIG. Raw materials were charged. The equipment conditions for each charging device are as shown in Table 1 below.

Table 2 below summarizes the effects of using the device of this invention under the equipment conditions shown in Table 1 above. (1) Using the charging device of the first embodiment. (2) When the charging device of the second embodiment is used, the particle size segregation degree (-), average Classification degree (-),
and carbon segregation degree (-), as well as production rate (t/h-i), return ore intensity (glare/
1) and the basic unit of coke breeze (kg/t),
Furthermore, as an index representing the equipment condition of the charging equipment, maintainability, including adhesion of sintering raw materials, wear resistance of the chute, and versatility of the chute material, etc., was shown.

In addition, as comparative examples, as mentioned above, ■ When using the flat plate chute charging method, ■ When using the two-stage charging method, ■
The results are shown using the same index as the above-mentioned index when using the horizontal wire tensioning method and (2) using the Rondo vertical tensioning method.

The degree of particle size segregation (-) is the value obtained by dividing the difference between the average particle size of the pseudo particles in the lower layer and the average particle size of the pseudo particles in the upper layer by the average particle size of the pseudo particles of all the charged sintered raw materials, and is calculated as follows: ■It is defined as in the formula, and a large value indicates that the grain size is segregated.

In addition, the average classification degree (-) is the value obtained by dividing the average value of the index representing the spread of the particle size distribution of pseudo particles in each layer by the index representing the spread of the particle size distribution of the charging raw material, and is calculated by the following equation 0. It is defined as follows, and large values are classified. That is, this shows that the variation in particle size distribution of pseudo particles at each position within the pallet is reduced.

■Average classification = index that represents the spread of particle size distribution of the charged raw material Here, the index that represents the spread of particle size distribution is, for example, Rosin-Ram
This shows the uniform number in the mler distribution formula, and Table 2, which will be described later, uses this.

Further, the degree of carbon segregation (=) is the value obtained by dividing the difference between the carbon concentration in the upper layer and the carbon concentration in the lower layer by the carbon concentration of the total sintering raw material charged, and is defined as the following equation 0, A large value indicates that carbon is segregated.

0 force - Bonn segregation degree = Also, in the equipment situation of the charging equipment shown in Table 2, ○
The mark indicates good quality, the Δ mark indicates slightly poor quality, and the X mark indicates poor quality.

As is clear from Table 2, when the embodiment of the present invention is used, compared to Comparative Examples Carbon segregation degree (-) when using the two-stage charging method of Comparative Example ■, and average classification degree when using the Rondo vertical charging method of Comparative Example ■ (
Except for =), particle size segregation (=), average classification degree (-), and carbon segregation degree (-) were all improved, and as a result, when using the two-stage charging method of Comparative Example ■, Production rate (1/h-
b), return ore consumption rate (kg/l), and coke breeze consumption rate (kg/t) have all improved6.Furthermore, (1)
) When the charging device of the first embodiment is used, maintainability including versatility of chute material is excellent, and (2)
) When the charging device of the second embodiment is used, the adhesion of the sintered raw material and the wear resistance of the chute are excellent.M! It was done.

"Effects of the Invention" As described above, according to the apparatus of the present invention, the radius of curvature is constant or the radius of curvature is in the vertical direction of the chute so that the upper surface of the chute on which the sintered raw material slides is concave. Since it is curved in a spiral shape that increases in proportion to the 0th power to the 1st power (not including 0 and 1st power) of the position of The proportion of the horizontal component of the velocity can be increased, and as a result, the horizontal movement velocity of the sintered raw material at the lower end of the chute can be increased.

Therefore, particle size segregation and carbon segregation in the layer height direction of the sintered raw material charged into the pallet are improved, the thermal history is made uniform, and the production yield of sintered ore is improved. The productivity of sintered ore can be improved by improving the variation in the particle size distribution of the granulated pseudoparticles.

Furthermore, the device of the present invention allows conventional chutes to be easily modified at low cost, is easy to maintain, has little adhesion of sintering raw materials, and has excellent wear resistance of the chute. This invention brings about many industrially useful effects such as, and is a highly effective invention.

[Brief explanation of drawings]

The drawings show the technical contents of the present invention, and FIG. 1 is a schematic side view showing the first embodiment of the device of the present invention, and FIG.
The figure is a schematic side view showing the second embodiment, Figure 3 is a chart showing the relationship between the multiplier for determining the radius of curvature from the vertical position of the chute and the particle size segregation rate, based on the amount of each raw material cut out, and Figure 4 is the conventional FIG. 2 is a schematic side view showing the device. The respective symbols in these drawings are as follows. DESCRIPTION OF SYMBOLS 1... Surge hopper, 2... Roll feeder, 3... Chute of conventional technology, 4... Bullet, 5... Endless moving grate, 6... Sintering raw material, 7... Sintering Raw material layer, 8... Wind box, 9... Ignition furnace, 11, ■... Chute according to the present invention.

Claims (1)

[Claims] The sintering raw material stored in the hopper is cut out from the hopper and fed into a continuously moving pallet, with its upper end positioned directly below the hopper and its lower end positioned above the pallet. In the raw material charging device for a sintering machine consisting of a chute, the radius of curvature is constant so that the upper surface on which the sintered raw material slides down is a concave surface, or the radius of curvature is set to the 0 to 1 power of the vertical position of the chute ( 1. A device for charging a raw material into a sintering machine, characterized in that the device is curved in a spiral shape increasing in proportion to (not including 0 and 1st power).