JPH0120204B2 - - Google Patents

Description

[Detailed description of the invention] In the top charging device of a blast furnace, normally,
As shown in FIG. 1, raw materials are charged from a certain direction by a charging conveyor 1 and stored in a hopper 2. At this time, the raw material draws a falling trajectory with a horizontal velocity component due to the movement of the charging conveyor.
The falling trajectory differs depending on the particle size of the raw material, and therefore the falling positions of large, medium and small raw material lumps differ. Also, depending on the horizontal velocity component of the raw material,
As shown in FIG. 1, the raw material distribution within the hopper also has an asymmetrical shape. In this way, charging conveyor 1
If the raw material is dropped from the hopper to the hopper 2, the raw material will be unevenly distributed within the hopper.

If this non-uniform distribution is carried into the blast furnace as it is, it will become an extremely serious obstacle to efficiently maintaining the reaction inside the blast furnace, so various efforts have been made to prevent this. As one preventive measure against this, a swing chute is generally adopted. The rotating chute is used, for example, in a conventional two-bell valve seal type charging device as shown in FIG. A fixed hopper 2' equipped with four gate valves 4 is installed at the bottom of the fixed hopper 2', and further, four seal valves 5, a small bell hopper 6, a small bell 7, a large bell hopper 8, and a large bell hopper are installed at the bottom of the fixed hopper 2'. Many types are seen in which a double seal mechanism consisting of a combination of bells 9 is installed to allow the raw material to fall into the furnace 10. In this method, since the rotating chute 3 can be rotated continuously, the raw material is distributed in the circumferential direction within the fixed hopper 2', and the raw material distribution is improved compared to the case without the rotating chute as shown in Fig. 1. uniformity is improved. Another example of a swing chute is a two-bell chute of the type shown in FIG.
There is a valve seal type charging device, and a fixed hopper 2'' equipped with a plurality of gate valves 4 is installed at the bottom of the charging conveyor 1, and a seal valve 5 and a small bell hopper 6 are installed at the bottom of the fixed hopper 2''. , 2 consisting of a small bell 7, a large bell hopper 8 and a large bell 9
There is a type in which a heavy seal mechanism is installed and a swing chute 3 is installed inside the small bell hopper 6. Similar to the charging device shown in FIG. 2, this method also improves the uniformity of the raw material distribution inside the small bell hopper 6 compared to the case without the rotating chute.

Note that 11 in FIGS. 2, 3, and 4 is a drive device for the gate valve 4.

As described above, in the two-bell valve seal type charging device, by equipping the rotating chute 3 in the raw material falling path, the material distribution in the hopper under the rotating chute 3 is improved compared to the case without the rotating chute. It has become possible to improve the uniformity of However, with conventional swiveling chute it is not possible to obtain a completely uniform distribution within the hopper at the bottom of the swiveling chute. For example, in the conventional charging device shown in FIG. 2, when the exit direction of the rotating chute 3 is at position A shown in FIG.
When the material is in the position , the falling direction of the raw material from the drop port 13 of the charging conveyor 1 and the direction of the outlet of the rotating chute 3 are opposite to each other, so the flow state of the raw material in the rotating chute changes. As a result, it is not possible to obtain a completely uniform distribution of the raw materials. To explain more specifically, when the material is at position A, the falling path of the raw material is curved compared to when it is at position B, which increases the flow resistance and makes it difficult for the raw material to flow. The falling state of the raw material changes depending on B. A similar phenomenon occurs in the charging device shown in FIG. 3, and in this device, as the swing chute 3 rotates, the relative relationship between the outlet of the swing chute, the gate valve 4, and the seal valve 5 changes. As a result, the falling state of the raw material in the rotating chute changes, making it impossible to obtain a completely uniform distribution.

The present invention solves the above-mentioned drawbacks of the conventional rotating chute, and achieves a rotating chute that makes it possible to obtain almost completely uniform distribution of raw materials. In a rotating chute for dropping raw material from a spout to a hopper, a raw material outlet is provided at the lower end of the rotating chute with a throttle part at the center of the swirl, and the throttle part is equipped with a throttle device provided on a throttle drive rod, A rotating chute for a bell-type blast furnace top charging device, characterized in that the rotating chute is provided with a raw material storage amount detection device, a control device is connected to the detection device, and a throttle drive device is connected to the control device. It provides:

First, the apparatus of the present invention will be explained with reference to the drawings. As an example, FIG. 4 shows a case where the swing chute according to the present invention is applied to the conventional charging device shown in FIG. 2. The rotating chute 3 has a simple, axially symmetrical structure with a nozzle-like constriction part 15 in the center of the lower part,
A bracket 19 is attached like a conventional swing chute, and the bracket 19 is supported by a support roller 20, and the swing chute drive device 2
It has a structure that allows it to rotate freely by driving it at 1. Also, under the swing chute 3,
Similar to the conventional charging device shown in FIG.
The raw materials are fed into the furnace through these.
Transported to 0. Furthermore, a cone-shaped throttle device 14 is installed inside the throttle section 15 of the swing chute 3, and the throttle device 14 is attached to the bell drive rod 12.
It is connected to the diaphragm drive device 16 through an diaphragm drive rod 22 provided on the outside of the diaphragm, and is structured to be able to move up and down freely. This squeezing device 14
The clearance between the throttle device 14 and the throttle part 15 can be freely changed by the vertical movement of the throttle device 14, and therefore the flow resistance of the raw material can be changed, and the amount of raw material stored in the rotating chute can be controlled by this function. be. In addition, the swing chute 3 is equipped with a detection device 17 that detects the amount of raw material stored in the swing chute, and a signal from the detection device 17 is sent to a control device 18, and a calculation mechanism in the control device 18 is sent to the control device 18. Accordingly, an operation signal for keeping the raw material storage amount within a certain range is transmitted to the drive device 16. The raw material is stored in the rotating chute 3 and falls into the fixed hopper 2' to form a uniform distribution.

Next, the effects of the present invention will be explained. In the present invention, as described above with respect to the conventional rotating chute, from the drop port 13 of the charging conveyor 1 in each direction of the outlet of the rotating chute 3, for example, in the direction A and the direction B in FIG. Since the flow path of the raw material to the outlet of the swirling chute is different, and therefore the flow resistance is different, the flow condition is different in the direction A and the direction B, and a uniform distribution cannot be obtained. However, in the present invention, by appropriately operating the throttle device 14, the flow resistance of the throttle section 15 is increased and the raw material can be stored in the rotating chute 3, so that the header effect of the stored raw material causes the raw material to fall. can be made uniform. In other words, when raw materials are stored in the rotating chute 3, the flow state of the raw materials from the outlet of the rotating chute 3 is determined approximately by the layer thickness of the stored raw materials and the relative relationship with the drop port 13 of the charging conveyor 1. Therefore, since there is almost no influence, a uniform falling state of the raw material can be obtained in any direction of the exit of the rotating chute 3, and therefore, a uniform distribution of the raw material can be obtained. Of course, the degree of uniformity improves as the storage amount increases, so it is desirable to increase the capacity of the swing chute 3 within a permissible range.

Furthermore, since the squeezing device 14 can be driven even while the rotating chute 3 is rotating, the squeezing device 14 can be freely changed in response to temporal changes in the particle size of the raw material, and the storage amount can always be kept within a certain range. It is possible to maintain the storage amount by immediately responding to changes in the raw material, and it is possible to maintain the stored amount and obtain a uniform distribution.

As described above, the present invention makes it possible to control the amount of raw material stored in the swing chute within a certain range by installing a throttle device that can be driven even while the swing chute is rotating. As a result, it is possible to obtain a uniform distribution of raw materials in the hopper under the rotating chute, so it is a useful invention that has an extremely favorable effect on the reaction inside the blast furnace, and has great practical value. .

Although the present invention has been described only in the case where it is applied to the embodiment of the charging device shown in FIG.
The same applies to the embodiment shown in the figure. Further, the present invention is not limited to the shape of the throttle device, and can be applied to any throttle device as long as the throttle device can be driven while the swing chute is rotating.

[Brief explanation of drawings]

Figure 1 is an explanatory diagram showing the falling state of raw materials from the charging conveyor, Figures 2 and 3 are general views of a two-bell valve seal type charging device using a conventional rotating chute, and Figure 4 The figure is an explanatory diagram of the case where the swing chute of the present invention is applied to the conventional charging device of FIG. 2. In the figure, 1 is a charging conveyor, 2 is a hopper, 2', 2'' are fixed hoppers, 3 is a rotating chute, 4 is a gate valve, 5 is a seal valve, 6 is a small bell hopper, 7 is a small bell, and 8 is a large Bell hopper, 9 is a large bell, 10 is inside the furnace, 11 is a gate valve drive device,
12 is a bell drive rod, 13 is a dropping port of the charging conveyor, 14 is a squeezing device, 15 is a squeezing part, 16 is a squeezing drive device, 17 is a detection device, 18 is a control device, 19 is a bracket, and 20 is a support roller. ,2
1 is a rotating chute drive device, and 22 is an aperture drive rod.

Claims (1)

[Claims] 1. In a rotating chute for dropping raw material from the raw material input port to the hopper of a bell-type blast furnace top charging device, a raw material outlet with a constriction part at the center of the swirl is provided at the lower end of the rotary chute, and a constriction part is provided in the constriction part. The driving rod is equipped with a throttling device, the rotating chute is provided with a raw material storage amount sensing device, a control device is connected to the sensing device, and a throttling drive device is connected to the control device. The rotating chute of the bell-type blast furnace top charging device.