JPH0130886B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a raw material charging device for a metallurgical shaft furnace such as a blast furnace.

Conventionally, raw materials charged into a blast furnace are temporarily stored in an ore storage tank 1 and a coke storage tank 2 shown in FIG.
From here, a predetermined amount is passed through the ore conveyor 3 or coke conveyor 4 to the surge hopper 5.
(for ore) or 6 (for coke),
From there, they are individually transferred to the top of the blast furnace by a charging conveyor 7.

As shown in FIG. 2, the transferred raw material is divided into approximately two parts in the width direction of the charging conveyor 7, stored in two fixed hoppers 9, and then transferred to the rotating chute 1.
0 on the small belt 11, and furthermore,
It is charged to the top of the furnace via a large belt 12.

In this way, it is expected that the raw material charged into the blast furnace will be uniformly distributed circumferentially within the furnace.

However, in actual equipment, grain size segregation occurs in the circumferential direction, as will be explained below.

That is, when ore and coke are charged into the surge hoppers 5 and 6 on the ore and coke conveyors 3 and 4, the third
As shown in the figure, large particles fall far away, and small particles fall towards you.

Therefore, within the surge hoppers 5, 6, the particle size of the raw material is segregated in the transport direction of the conveyors 3, 4 with the conveyor head as the center.

Ore stored in surge hoppers 5 and 6,
Coke is cut out at gate 13 and feeder 14
When the particles are discharged by the hoppers 5 and 6 and placed on the charging conveyor 7, the shape of the hoppers 5 and 6 presents a so-called "funnel flow," and there is particle size segregation in the longitudinal direction of the charging conveyor 7. However, the surge hopper 5,
6 The influence of particle size segregation during charging remains, and segregation exists.

Regarding these two types of segregation, one in the length direction and the other in the width direction, when the material passes through the head chute 8 shown in FIG. If the apex of the fork is located at the center position of the charge in the width direction on the charging conveyor 7, most of the grain size segregation in the width direction will be eliminated, but the particle size segregation in the width direction will enter the fixed hopper 9 as it is, and the charge in the two fixed hoppers 9 will be removed. Particle size deviation occurs between containers.

This passes through the rotating chute 10 to the small bell 1.
1. When the particles are charged into the furnace through the large bell 12, the particle size segregation is somewhat eliminated by the mixing action, but in reality it still remains.

Originally, the rotating chute 10 was installed to eliminate such segregation, but the reason why grain size segregation still remains is as follows.

In other words, in Fig. 4, if the mouth of the rotating chute 10 faces the fixed hopper 9 containing larger particles, the particles in the hopper closer to the mouth will naturally flow unnecessarily due to the flow behavior of the particles. Large particles are segregated and deposited on the bell 11.

This is because when the mouth of the rotating chute 10 faces in the opposite direction, the opposite phenomenon occurs, and this condition is carried over into the furnace via the small bell 11 and the large bell 12.

In view of the above-mentioned circumstances, the present invention eliminates the particle size segregation of ore and coke that occurs in the width direction of the charging conveyor 7 in the surge hopper 5 or 6 at this point, and smooths the particle size distribution in the circumferential direction in the blast furnace. , which was designed to achieve stable operation of blast furnaces, is characterized by the fact that if two symmetrical deposits are formed in the surge hopper 5 or 6 with the center axis of the hopper as the axis of symmetry, these deposits can be The charging conveyor 7 cancels each other out at the time of discharge.
This method takes advantage of the fact that no segregation occurs in the width direction.

This will be explained in detail below based on the drawings.

That is, FIG. 5 shows one embodiment of the present invention. In the figure, a box-shaped surge hopper 5 or 6 is installed on the charging conveyor 7, while a conveyor 3 or 4 is placed in the forward direction of the charging conveyor 7. is placed at right angles to.

Surge hopper 5 from conveyor 3 or 4
Alternatively, divide the raw material into two parts where it falls into 6,
A bifurcating chute 23 for branching into two streams flowing in opposite directions is installed below the conveyor 3 or 4 in such a manner that the flow of raw material is parallel to the conveyor 3 or 4.

That is, as clearly shown in the bird's-eye view of FIG. 6, the raw material is divided into two parts through the two-part chute 23, forming two deposits B and B' in the surge hopper 5 or 6.

By positioning the two-split chute 23 and the conveyor 3 or 4 so that the two deposits B and B' are formed at symmetrical positions with respect to the center axis of the surge hopper 5 or 6, the axis is aligned on the plane inside the tank. A symmetrical material deposit is formed.

By discharging such deposits B and B' onto the charging belt conveyor 7, grain size segregation in the width direction on the charging belt conveyor 7 can be eliminated.

FIG. 7 shows another embodiment in which the discharging direction is different from that of FIGS. The flow of raw materials is shown below.

In this case as well, there are 2 in the surge hopper 5 or 6.
By arranging the conveyor 3 or 4 and the chute 24 so that the central position of this accumulation is symmetrical with respect to the central axis of the surge hopper 5 or 6, two deposits B and B' are generated. Alternatively, the distribution of raw materials within 6 can be formed axially symmetrically.

In this way, the surge hopper 5 or 6
By forming axially symmetrical deposits B and B' within the charging conveyor 7, grain size segregation in the width direction can be prevented.

In the above embodiments, the ore or coke conveyor 3 or 4 is perpendicular to the charging conveyor 7, but even if they are oblique, the charging conveyor 7 can be moved by installing a similar chute 23 or 24. Segregation in the upper width direction can be eliminated.

Note that if these conveyors 3, 4, and 7 are installed in parallel, no segregation in the width direction on the charging conveyor 7 will occur, and this is outside the scope of the present invention.

Also, ore or coke conveyors 3, 4 and 2
Regarding the relative arrangement with the dividing chute 23, 24, an example has been described in which the direction of flow of the raw material adjusted by the conveyors 3, 4 and the chute 23, 24 is perpendicular or parallel; It will be easily understood from the above description that there is no need to limit the number of times.

However, in either case, the raw material must be divided into two approximately at the center of the ore or coke conveyor.

Furthermore, in the above embodiments, the feedstock flow is
The chute 23, 24 for dividing is composed of a box part for receiving the raw material and a groove-shaped chute part connected to the box part, but as is clear from the above explanation, the shape of the chute is limited to that shown here. It is not necessary, and the point is that it is sufficient to have the function of dividing the ore or raw material on the coke conveyors 3 and 4 into two approximately at the center of the conveyor, and the function of distributing and transporting the two in opposite directions. .

As described above, the purpose of the present invention is to form two deposits in the surge hoppers 5 and 6 symmetrically with respect to their central axes. It must be divided into two parts.

However, in order to fix the falling position, the above-mentioned two-part chute 23, 24 must be replaced by the surge hopper 5,
It is necessary to fix it in a certain position relative to 6,
On the other hand, the raw material is ore or coke conveyor 3,
4, the raw material may not necessarily be divided evenly if the two-divided chute 23, 24 is fixed due to deviation of the conveyor, deviation of the raw material on the conveyor, etc.

Therefore, the raw material distributor shown in Fig. 8 divides the raw material into two parts.
This is an example in which the chute 24 is equipped with a device for evenly distributing the material to the divided chute 23, 24, and the raw material distributor can be moved to the left or right according to the unevenness of the conveyor and the unevenness of the raw material on the conveyor. By making adjustments, it is possible to dispense the same amount of raw material without changing the drop position.

That is, the raw material distributor 15a shown in Fig. a uses a stone box, and by moving this distributor 15a in the width direction of the conveyors 3 and 4, the amount of raw material distributed to the left and right is adjusted.

Further, the raw material distributor 15b shown in Figure b has a wedge shape, and adjusts the amount of raw material distributed by moving in the width direction of the conveyor or by changing the inclination and changing the position of the apex.

As described above, the present invention is useful for preventing asymmetric particle size segregation in a tank that temporarily stores granular materials having a particle size distribution, and is useful for preventing, for example, a charging device for a shaft furnace for direct reduction, a shaft type lime It can be applied to charging equipment for firing furnaces, etc.

[Brief explanation of drawings]

Figure 1 is a layout diagram of the ore storage layer, coke storage tank, ore conveyor, coke conveyor, surge hopper, and charging conveyor. Figure 2 is a schematic diagram of the furnace top charging device. Figure 3 is the charging belt caused by the surge hopper. A perspective view showing grain size segregation in the width direction of the conveyor, FIG. 4 is a schematic diagram of particle flow from a fixed hopper to a circulating chute, and FIGS. 5 a, b and 6 are an example of a two-part chute according to the present invention plane of,
7 is a perspective view of another example of a two-part chute, and FIGS. 8a and 8b are explanatory views of the raw material distributor of the present invention. 7...Charging conveyor, 5,6...Surge hopper, 3,4...Belt conveyor, 23,24
...Two-part shoot.

Claims (1)

[Claims] 1. A surge hopper is provided which receives ore and coke to be charged into the blast furnace through a belt conveyor, temporarily stores a certain amount, and discharges it to the charging conveyor of the blast furnace. , in a blast furnace raw material charging device having an orthogonal or oblique arrangement, the falling raw material is divided into approximately two parts in the width direction of the belt conveyor at the position where each raw material falls from the belt conveyor into the surge hopper; A charging device for charging a surge hopper in a blast furnace raw material charging device, which is equipped with a chute that adjusts the falling flow so that the falling position of the raw material is approximately symmetrical with respect to the center axis of the surge hopper.