JPH0616912Y2 - Bellless blast furnace charging device - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to a charging device for a bellless blast furnace capable of optimizing the charging distribution of blast furnace charging.

[Conventional technology]

Regarding the furnace top charging device for charging raw materials into the blast furnace,
Conventionally, the 2-bell type or the 3- or 4-bell type for coping with the high pressure of the blast furnace has been the mainstream.

However, in recent years, a bell-less type charging device that has excellent controllability of the distribution of the contents inside the furnace and can contribute to the reduction of the equipment cost has appeared and is widely used.

Many improved techniques relating to this bellless charging device have been proposed. For example, in Japanese Patent Publication No. 56-25245, inside a swirling cone 50 installed at the top of the bellless blast furnace A, as shown in FIG. The swivel base 51 is installed in
It is disclosed that a vertical chute 52 provided so as to coincide with the furnace axis direction is provided with a tilting distribution chute 53 that rotates integrally with the swivel base 51 and is tiltable.

On the other hand, conventionally, the distribution chute 53 has a length of 3 to 5 m.
A straight chute is adopted, and the blast furnace raw materials of ore, sinter, and coke are dispersedly charged under the same conditions by rotating around the furnace axis in the right or left rotation direction at a rotation speed of around 10 rpm. It was a thing.

[Problems to be solved by the device]

However, in the conventional bellless charging device,
Ore and sinter with high specific gravity have a large drop energy, so even if they fall onto the surface of the charge, they flow toward the furnace wall side, causing poor air permeability on the wall side and unstable blast furnace operation. It was a factor.

Further, especially in a center-feed type bellless blast furnace, since the charging material falls directly from the raw material control gate onto the distribution chute, the sliding speed on the chute is high and the effect is likely to occur.

Further, Japanese Patent Application Laid-Open No. 49-23708 proposes to provide a deflector plate at the tip of the distribution chute, but since the charging material frequently collides with the deflector plate, it is not practical in terms of life of the deflector plate. .

Further, in Japanese Patent Application Laid-Open No. 61-272585, the distribution chute is made movable in the radial direction, and its discharge port is opened in the tangential direction of its rotation locus and in the direction opposite to the rotation direction of the raw material distribution chute. Therefore, it is proposed that the charging distribution be made uniform in the radial direction. However, the device for moving the distribution chute in the radial direction becomes complicated,
Since the equipment cost is high and the dough is basically charged along the rotation trajectory of the discharge port, appropriate charge distribution control is performed unless frequent radial chute movement control is performed. Hard to do.

Therefore, an object of the present invention is to provide a charging device for a bellless blast furnace, which can prevent the segregation of the charging by adjusting the charging speed and the dropping position according to the specific gravity of the blast furnace raw material and can perform stable blast furnace operation. To provide.

[Means for Solving the Problems]

The above-mentioned problem is a charging device for a bellless blast furnace in which a blast furnace raw material is charged and distributed by a distribution chute that is provided on the furnace top so as to be rotatable about the furnace axis and tiltable in the vertical direction. By forming a dogleg shape or a bow shape having a bent portion in the middle, the angle between the discharge direction and the trajectory of the discharge port is 10 to 85 degrees, and the swivel direction of the distribution chute is reversible. Can be resolved.

[Action]

Generally, in a charging device for a bellless blast furnace, as shown in FIG. 5, when the blast furnace raw material is charged while the distribution chute 1 is swung at a constant speed, the vertical component speed V ₁ and horizontal component of the charging speed are set. The relationship between the speed V ₁₁ and the tilt angle β is as shown in FIG.

As is clear from Fig. 7, it is understood that there is always a difference of 0.3 m / s in the speed between the ore having a large specific gravity and the coke having a small specific gravity. This difference in specific gravity causes segregation of the charge.

In the present invention, the ore with a high specific gravity has a slow charging speed to reduce the falling energy, and the coke with a low specific gravity has a high charging speed. It has a bent shape with a bent portion or an arc shape, and the discharge direction of the charging material can be changed by the distribution chute, and the turning direction can be reversed.

Therefore, even in the case of turning at the same speed, in the case of the coke having a small specific gravity, the same direction as the bending direction (6th
When rotated and charged in the direction of the arrow shown in Figure (b),
The ejection speed of the charge is combined with the turning speed to accelerate the ejection speed. On the other hand, in the case of an ore having a large specific gravity, if the ore is charged by turning in the direction opposite to the bending direction (the direction of the arrow shown in FIG. 6 (c)), the ejection speed of the charged material is combined with the turning speed. The speed is reduced. As described above, in the present invention, the falling energy can be adjusted by changing the charging speed according to the specific gravity of the charging without changing the turning speed, so that the knitting can be adjusted.

It is needless to say that the drift adjustment can be performed more effectively by providing the turning speed adjusting function as in the conventional case.

[Specific configuration of device]

 Hereinafter, the present invention will be further clarified by examples.

In the present invention, the shape of the distribution chute is changed with respect to the conventional bellless charging device shown in FIG.

The distribution chute 1'of the bellless charging device before the change is a linear distribution chute as shown in Fig. 5 (a), which charges the blast furnace raw material while turning counterclockwise and its horizontal position. The charging speed V is coke 4.5 m / s at a tilt angle β50 °,
The ore was 4.8 m / s.

In this embodiment, the conventional linear type distribution chute 1'is replaced with a bent type distribution chute 1 shown in FIGS. 1 to 4, and the turning direction thereof can be reversed.

That is, the distribution chute 1 according to the present embodiment has a semicircular cross section as shown in FIG. 3, and as shown in FIG. 4, its discharge direction and the locus L of the discharge port 1a in a plane.
The angle θ formed by and is set to 10 to 85 degrees, and is bent in a substantially V shape, and the joint materials 3, 3 ... For maintaining the shape are provided in appropriate places across the side walls. .

The distribution chute 1 is capable of reversing the turning direction. As this concrete means, there can be mentioned an example in which a swivel-based swivel drive means, which is also used in the past, and a normal motor are remodeled so as to be freely reciprocal. Further, as the means for tilting the distribution chute in the vertical direction, the conventional example can be used as it is.

On the other hand, in the present invention, the bending or bending mode is not limited within a range in which the angle θ formed by the discharge direction of the distribution chute 1 and the locus L of the discharge port 1a is 10 to 85 degrees. However, as in the distribution chute disclosed in Japanese Patent Laid-Open No. 61-272585, in a mode in which it is bent at a right angle in the middle, wear at the bent portion is severe, and the life and maintenance are reduced. It cannot be adopted at all. Therefore,
It is desirable that the bent portion is bent gently or entirely so that the charging material can drop smoothly.

As a result of changing the distribution chute 1 according to the present invention as described above, when charging coke, the distribution chute 1 is rotated clockwise as shown in FIG. As a result of turning at a turning speed and charging, the horizontal charging speed was V = 4.8 m / s.

On the other hand, when charging ore and sinter, the result of turning the distribution chute 1 counterclockwise as shown in Fig. 6 (c) and turning at the turning speed before change The horizontal charging speed was 4.4m / s, and the charging speed was relaxed and the falling energy was reduced, so the sinter that had flowed into the furnace wall side disappeared and stable operation became possible.

In the present invention, the angle θ formed by the discharge direction and the locus L of the discharge port 1a is 10 to 85 degrees, more preferably 60 to 80 degrees. When the angle θ is less than 10 degrees, the length of the chute becomes large, and when it exceeds 85 degrees, the bending effect of the distribution chute cannot be expected in comparison with the conventional example.

The twist angle α shown in FIG. 1 is preferably 5 to 30 degrees.

In the case of the device of the present invention, since the blast furnace feed-out direction is not orthogonal to the blast furnace wall, there is less risk of damaging the furnace wall, and the charging surface layer line of the furnace wall can be adjusted. It will be easy. Further, since it is possible to carry out the equipment by using almost the same equipment as the conventional equipment without requiring a particularly complicated equipment modification, new equipment cost is small and economical, and maintenance is easy.

[Effect of device]

As described above in detail, according to the present invention, it is possible to prevent the segregation of the charge by only a simple design change related to the distribution chute.
It can contribute to stable and efficient blast furnace operation.

[Brief description of drawings]

1 is a plan view of a distribution chute according to the present invention, FIG. 2 is a side view of FIG. 1, FIG. 3 is a view taken along the line III-III of FIG.
FIG. 4 is a plan view of an arrangement example of the distribution chute according to the present invention,
FIG. 5 is a diagram showing a state of charging the blast furnace raw material by the bellless charging device, FIG. 6 (a) is a diagram showing a charging state of the bellless charging device before the change in the embodiment, and FIG. 6 (b). ) ~ (C)
FIG. 7 is a diagram showing a charging state in the bellless charging device after the change in the embodiment, and FIG. 7 shows a relationship between the vertical component speed V ₁ and the horizontal component speed V ₁₁ of the blast furnace raw material charging speed and the tilt angle β. FIG. 8 and FIG. 8 are views showing a conventional bellless charging device. 1 ... Distribution chute, 1a ... Discharge port, 2 ... Blast furnace, 3
...... Splice material

Claims (1)

[Scope of utility model registration request] 1. A bellless charging device for a blast furnace, in which a charging chute for controlling the charging of blast furnace raw materials is provided by a distribution chute provided on the top of the furnace so as to be rotatable about the furnace axis and tiltable in the vertical direction. It has a bent or arcuate shape with a bent portion in the middle, the angle formed by the discharge direction and the trajectory of the discharge port is 10 to 85 degrees, and the swivel direction of the distribution chute is reversible. Belleless blast furnace charging device characterized by