JP3324685B2 - Dust collection method and dust collection device in ladle refining process - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for collecting dust generated in a ladle refining process such as the LF method.

[0002]

2. Description of the Related Art Ladle refining processing involves placing a lid on a ladle to prevent the temperature of molten steel stored in the ladle from dropping, and to open the ladle from the opening above the lid. The electrode rod is inserted into the ladle to heat and refine the steel in the ladle.

At this time, since dust is generated by heat refining, it is necessary to collect the dust. In the conventional dust collecting method, as shown in FIG. 5, a suction duct 51 is directly connected to the lid 50, and dust in the lid 50 is directly and forcibly sucked to collect dust.

[0004] Argon gas is blown into the ladle 52 to perform gas purging. Reference numeral 54 denotes an electrode rod for heating.

[0005]

However, the lid 50
When the dust in the inside is forcibly sucked, the air is sucked from between the lid 50 and the ladle 52, so that the sucked air has an adverse effect such as the introduction of nitrogen into the molten steel and the progress of oxidation of the slab. . For this reason, conventionally,
It is necessary to manually seal the gap between the ladle 52 and the lid 50 with the refractory material 53, resulting in heavy labor.

SUMMARY OF THE INVENTION The present invention has been made in view of such a problem, and provides a dust collecting method and apparatus which can suppress air suction into a ladle without sealing between the ladle and a lid. The task is to provide.

[0007]

According to a first aspect of the present invention, there is provided a method for collecting dust in a ladle refining process, the method comprising: removing dust generated when performing heat refining in a ladle; a method of dust collection in a state in which no sealing between the ladle and the lid, without forcing sucking the dust in the lid, dust overflowing out of the opening of the lid, are formed above the lid After being guided upward by an artificial tornado flow, dust is collected by forcible suction with a suction device.

According to a second aspect of the present invention, there is provided a dust collecting apparatus in a ladle refining process, which collects dust generated when performing heat refining in a ladle without sealing between the ladle and a lid. an apparatus, human for inducing dust overflowing out of the opening of the lid without forcing sucking the dust in the lid upwards
A dust guiding means for forming the tornado flow of the work above the lid, and a dust collecting hood is arranged above the dust guiding means and
And a dust suction device for forcibly sucking the induced dust .

According to these inventions, since the dust overflowing from the lid is guided upward and is forcibly sucked, it is not necessary to forcibly suck the dust in the lid. Atmospheric suction is avoided.

[0010]

[0011] For example, a cylindrical air curtain in which the shaft up and down by whirling airflow formed by the air curtain to prevent the dust overflowing from the lid opening to dissipate to the outside. Furthermore, by forming a negative pressure region in the vertical direction along the center of the swirling airflow by suction by the dust suction device disposed above, a continuous upward upward while converging the vortex of the swirling airflow in the negative pressure region. and artificial tornado flow
And, to induce the dust upward by tornado flow of artificial
You .

Here, as shown in FIG. 4, the swirling air flow can be formed by regulating the flow direction 30 of the gas ejected from each air blowing head 31 in a direction circumscribing one circle C. The reason why the number of blowing heads is three or more is that swirling airflow cannot be formed with two or less blowing heads.

[0013]

Next, embodiments of the present invention will be described with reference to the drawings. First, the configuration will be described.
As shown in FIGS. 1 and 2, a lid 2 is provided on a ladle 1, and four air blowing heads 3 constituting dust guiding means are erected above the lid 2.

As shown in the plan view of FIG. 3, the lower ends of the four air blowing heads 3
And a blower fan 5 is connected to the head communication pipe 4.

A plurality of nozzles 6, for example, twenty nozzles 6 are attached to the air blowing head 3 at predetermined intervals along the longitudinal direction (vertical direction), and the jetting directions of the plurality of nozzles 6 are set. Are directed in the same direction in three units of the air blowing head.

The direction of jet from each nozzle 6 is as follows:
As shown in FIG. 3, the circle C is circumscribed and circulates. A dust collecting hood 10 is disposed above the four air blowing heads 3.
The dust collecting hood 10 is connected to a dust collecting fan 9 (not shown) via a dust collecting duct 11. The dust collecting hood 10 is
It can be moved laterally. Reference numeral 12 indicates the traveling rail.

Here, reference numeral 13 indicates the position of the electrode rod,
Numeral 14 indicates the position of the Ar gas blowing device. That is, the electrode rods 13 and the like are arranged near the opening of the lid 2. However, in the dust guiding means of the present embodiment, only the four air blowing heads 3 are erected, so that the electrode rods 13 and the like are provided. Dust guidance means can be set without interference with equipment,
In addition, dust can be guided upward. The air blowing head 3 and the electrode rod 13 are movable in the vertical direction and the like.

In the apparatus having the above structure, the blower fan 5
Is activated to eject air from each nozzle 6,
A cylindrical swirling airflow is formed with its axis pointing up and down. Further, by operating the dust collection fan 9, the air of the swirling airflow is sucked upward, so that the inside of the swirling airflow becomes a negative pressure region and an artificial tornado flow toward the dust collection hood 10 is formed.

In this state, when the heating and refining is performed in the ladle 1, dust is generated by the heating and refining, and the dust overflows from the opening of the lid 2, but is guided to the artificial tornado flow. Then, the dust moves upward, and at a position away from the lid 2, the dust is sucked into the dust collection duct 11 through the dust collection hood 10 by the forced suction by the operation of the dust collection fan 9.

As described above, in the present invention, since the dust is guided to a position distant from the ladle 1 and the lid 2 and then the dust is forcibly sucked, the lid 2 and the lid 2 are forcibly sucked for dust collection. The formation of a negative pressure in the ladle 1 is avoided. For this reason, the intake of the atmosphere into the ladle 1 can be suppressed without sealing the space between the lid 2 and the ladle 1 with a refractory as in the related art.

The dust guiding means for guiding the dust overflowing from the lid 2 upward is not limited to the one using the artificial tornado flow described above. Other means may be adopted as long as the means can be guided to.

The number of the air blowing heads 3 is not limited to four, but may be three or five or more.

[0023]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Actually, a case where dust is collected by the dust collecting method according to the present invention and a case where dust is collected directly from a lid 2 as in the prior art (a seal made of a refractory material is provided between the lid 2 and the ladle 1). When the atmosphere gas in the ladle 1 was measured, the results shown in Table 1 below were obtained.

Nos. 1 to 4 are the results obtained by the conventional dust collecting method, and Nos. 5 to 7 are the results using the dust collecting apparatus according to the present invention.

[0025]

[Table 1]

As can be seen from Table 1, when the dust collector according to the present invention is used, the uptake of oxygen and nitrogen is small and the amount of argon gas is large even though the sealing operation with the refractory is not performed. Therefore, it can be seen that the gas purge with the blown argon gas is also working effectively.

[0027]

As described above, when the dust collecting method and the dust collecting apparatus in the ladle refining process of the present invention are employed,
There is an effect that dust generated by heating and refining can be collected while avoiding suction of the air into the ladle.

For this reason, the sealing work between the ladle and the lid, which has been a heavy labor, with the refractory material becomes unnecessary .

[Brief description of the drawings]

FIG. 1 is a side view showing a dust collector according to an embodiment of the present invention.

FIG. 2 is a side view showing the dust collector according to the embodiment of the present invention.

FIG. 3 is a plan view showing an arrangement of an air blowing header and the like according to the embodiment of the present invention.

FIG. 4 is a diagram for explaining a swirling airflow.

FIG. 5 is a view for explaining a conventional dust collection method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ladle 2 Lid 3 Air blowing head 4 Head communication pipe 10 Dust collection hood 11 Dust collection duct

Claims (2)

(57) [Claims] 1. A method of collecting dust generated during heating and refining in a ladle without sealing the gap between the ladle and the lid, without forcibly sucking the dust in the lid. dust overflowing out of the opening of the lid <br/>, formed above the lid
A dust collecting method in a ladle refining process, wherein the dust is collected by forcibly sucking with a suction device after being guided upward by an artificial tornado flow. 2. A device for collecting dust generated during heating and refining in a ladle without sealing between the ladle and the lid, wherein the dust in the lid is not sucked without forcibly sucking the dust. from the opening of the artificial for guiding the dust overflowing out above
A dust guiding means that forms a tornado flow above the lid, and a dust collecting hood is placed above the dust guiding means to guide it upward
And a dust suction device for forcibly sucking the collected dust.