JPH10267541A - Assist burning part structure for electric furnace - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a stationarily disposed state of scrap in a front area of a side burner and hence to prevent erosion of a burner cooling box or the side burner due to flame reflection by providing a rebounding part for the scrap at an upside of the burner. SOLUTION: A rebounding part 12 and space 13 protruding toward the inside of the electric furnace are provided at an upside wall position from a mount of a side burner 2. In the case of charging scrap in the furnace, the scrap is brought into contact with the part 12 and space 13, rebounded and separated from the burner 2. Thus, the burner 2 itself and a burner cooling box around the burner 2 are not eroded.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of a combustion supporting portion used in an electric furnace.

[0002]

2. Description of the Related Art As a steel making method in an electric furnace, there is a method of promoting melting by using not only electric energy but also an auxiliary combustion method. As one of the auxiliary combustion methods, there is a method in which one or a plurality of side burners 51 facing the inside of the furnace are arranged on a furnace wall 50 as shown in FIG. As the side burner 51, generally, a fuel such as a petroleum-based fuel (which may be a gas fuel, a liquid fuel, or a fixed fuel) and oxygen are injected, mixed, and burned.

[0003] A copper or steel panel 53 having a water-cooled box structure is provided on at least an upper side of the furnace wall 50 including around a mounting portion of the side burner 51. It can withstand radiant heat. Recently, only a portion of the panel 53 surrounding the periphery of the side burner 51 is divided and formed as a burner cooling box 55.

[0004]

When the scrap S is put into the furnace by a bucket (not shown) or the like, the scrap S which is stationary in front of the side burner 51 is relatively large or heavy. If there is, the flame of the side burner 51 is reflected on the scrap S, and the burner cooling box 55 and the nozzle tip of the side burner 51 may be melted.

[0005] Therefore, replacement or maintenance of the eroded parts is required, which is troublesome, and has the disadvantage that the operating time of the electric furnace is reduced due to the downtime. In addition, a rise in running costs due to replacement of parts has naturally caused. When the scrap S fixed in the front area of the side burner 51 is small or lightweight, the scrap S is blown off by the injection pressure from the side burner 51 or is immediately melted by the flame immediately after ignition. It doesn't matter. Also, even if they are not avoided by these methods, about 1 may be required due to melting by electric energy progressing in the center of the furnace.
Since the scrap S is removed from the front area of the side burner 51 within a short time of 0 second or less, there is little problem.

However, if the scrap S forms a bridge in the front area of the side burner 51 or its stationary state is backed up by being entangled with the large or heavy scrap S, the scrap S is small or light. , Continues to exist for a predetermined time (problem if it is longer than 20 seconds) in the front region of the side burner 51, and as a result, the side burner 51
This may cause flame reflection and cause the above-described melting and the like.

On the other hand, most of the side burners 51 are of a type in which fuel and oxygen are ejected and then mixed and burned in the front area thereof. The stationary state itself has led to making the side burner 51 difficult to ignite and deteriorating the combustion efficiency. The present invention has been made in view of the above circumstances, and prevents erosion of a burner cooling box, a side burner, and the like, so that replacement or maintenance of the component can be made unnecessary. An electric furnace which is capable of preventing a decrease in electric furnace operating efficiency, a rise in running costs due to replacement of parts, and the like, as well as ensuring ignition of a side burner and improving combustion efficiency. It is an object to provide a combustion support structure.

[0008]

According to the present invention, the following technical measures have been taken in order to achieve the above object. That is, in the structure of the assisting portion of the electric furnace according to the present invention, since the rebound portion is provided in a protruding manner at the wall position above the side burner,
When the scrap is put into the furnace, or when the scrap which has been set in the stationary state after being put into the furnace collapses, the rebound portion rebounds the falling scrap to keep it away from the side burner.

Therefore, in the front area of the side burner,
This prevents the scrap from reaching a stationary state that leads to various problems, and prevents the scrap itself from entering the front area of the side burner in the first place. Therefore, it is possible to prevent the burner cooling box and the side burner from being melted and damaged due to the flame reflection.

Further, it is possible to prevent poor ignition of the side burner and deterioration of the combustion efficiency. This bounce part,
When formed by the upper water-cooled panel disposed above the side burner, the members can be shared, and there is an advantage that the furnace structure can be suppressed from becoming complicated and large. On the other hand, if a space having the same amount of protrusion as the rebound part is provided between the upper and lower parts of the rebound part and the side burner, when the scrap moves in the furnace, this is generated in the front area of the side burner. It is also possible to prevent the state of being in a stacked state.

[0011] Therefore, a mixture space of a predetermined size can be secured in the front region of the side burner, and the ignition failure of the side burner and the deterioration of the combustion efficiency can be more surely prevented.
Can be prevented. If this space portion is formed by a burner cooling box surrounding the periphery of the side burner mounting portion, members can be shared, and there is an advantage that the furnace body structure can be suppressed from becoming complicated and large.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a furnace wall 3 to which a side burner 2 is attached in an electric furnace 1 having an auxiliary combustion section structure according to the present invention. A burner cooling box 6 having a burner insertion hole 5 is provided to surround the burner cooling box 6, and an upper water cooling panel 8 and a lower water cooling panel 9 are provided above and below the burner cooling box 6.

Each of the burner cooling box 6 and the upper and lower water cooling panels 8 and 9 is made of copper or steel or the like, and has a cavity 10 therein so that cooling water can pass therethrough. Now, the lower water cooling panel 9
In the description, it is assumed that the upright wall portion 9a facing the inside of the furnace is formed so as to match the reference inner surface W as the furnace wall 3;
Are formed so as to protrude inward from the furnace wall reference inner surface W. The standing wall portion 8a is inclined so that the degree of protrusion toward the inside of the furnace increases as going from the furnace top side to the furnace bottom side.

For this reason, the upper water-cooled panel 8 has a rebounding structure having a protruding portion from the furnace wall reference inner surface W by the standing wall portion 8a and a cavity 10 provided on the back side of the standing wall portion 8a. The part 12 is provided integrally. By providing the rebound portion 12 in this manner, when a scrap (not shown) is charged into the furnace,
At the time when the scrap which has been set in a fixed state after the charging falls down in front of the side burner 2 due to collapse or the like accompanying melting progress of the furnace center, the rebound portion 12 rebounds these scraps and the side burner 2 Keep away from the front.

Therefore, regardless of the size and weight of the scrap, the front area of the side burner 2 is prevented from reaching a stationary state in which the scrap leads to various problems. The scrap itself is prevented from entering the front area of the vehicle. In the present embodiment, the amount of protrusion from the furnace wall reference inner surface W at the lowermost portion of the rebound portion 12, that is, at the portion where the degree of protrusion into the furnace is the largest, was about 250 mm. However, the amount of protrusion can be appropriately changed within a range of about 150 mm to 350 mm.

On the other hand, in the burner cooling box 6,
A portion of the upright wall portion 6a facing the inside of the furnace, which is above the burner insertion hole 5, that is, the rebound portion 12 and the side burner 2
Is formed so as to project inward of the furnace from the reference inner surface W of the furnace wall 3. The amount of protrusion of the upright wall portion 6a is substantially equal to that of the rebound portion 12 described above.

For this reason, the burner cooling box 6 has a portion protruding from the furnace wall reference inner surface W by the upright wall 6a and the cavity 1 provided on the back side of the upright wall 6a.
0 is integrally provided with the space portion 13 having the configuration of “0”. In this space portion 13, the upper part of the burner insertion hole 5 is formed as a smooth curved surface.

If the space 13 is provided in this way, even if the scrap moves when the scrap collapses as the melting of the furnace center progresses, the scrap is moved to the space before the furnace wall reference inner surface W. The possibility of contact with the side burner 2 is increased, and as a result, the possibility of deposition in the front area of the side burner 2 is reduced. Therefore, a mixture space of a predetermined size can be secured in the front region of the side burner 2.

As described above, according to the present invention, the side burner 2 is provided by providing the rebound portion 12 and the space portion 13.
It is unlikely that the scrap is fixed in the front region of the above, so that the flame of the side burner 2 is reflected and the burner cooling box 6 and the side burner 2 themselves are not melted. In addition, since a mixture space is secured in the front region of the side burner 2, the side burner 2 does not suffer from poor ignition or deterioration of combustion efficiency.

Incidentally, the present invention is not limited to the above embodiment. For example, the upper water cooling panel 8 and the rebound portion 12, and the burner cooling box 6 and the space portion 13 may be formed as separate members. In addition, the upper water cooling panel 8 and the burner cooling box 6 can of course be integrally formed, but the rebound portion 12 and the space portion 13 can also be integrated with each other. In this case, the upper water cooling panel 8, the burner cooling box 6, the rebound part 12, the space part 13
Can also be integrated.

The formation of the hollow portion 10 for allowing the cooling water to flow into the inside of the rebound portion 12 or the space portion 13 is not limited, and the material for forming these is not limited. Bounce part 12
The cross-sectional shape of the side portion of the space portion 13 and the dimensions thereof can be appropriately changed. Therefore, the protrusion amount of the space portion 13 can be made somewhat smaller than the protrusion amount of the rebound portion 12, or can be made larger.

The structure and the like of the side burner 2 are not limited at all.

[0023]

As is apparent from the above description, in the structure of the combustion assisting portion of the electric furnace according to the present invention, since the rebound portion for scrap is provided above the side burner, the scrap is formed in front of the side burner. The stationary state is prevented, so that the burner cooling box and the side burner due to the flame reflection are prevented from being melted. for that reason,
Eliminates the hassle of replacing and maintaining eroded parts,
Also, the operating efficiency of the electric furnace can be increased. Of course, it is possible to prevent the running cost from rising due to the replacement of parts.

Further, the ignition of the side burner can be ensured and the combustion efficiency can be improved. On the other hand, if a space is provided between the bounce part and the side burner,
Since accumulation in the front area of the side burner due to the movement of the scrap can be prevented, a space for the air-fuel mixture can be secured, and the ignition of the side burner can be reliably performed and the combustion efficiency can be improved.

If the rebound portion and the space portion are integrally formed by an upper water-cooled panel or a burner cooling box, there is an advantage that the structure and size of the furnace body can be suppressed.

[Brief description of the drawings]

FIG. 1 is a sectional side view showing a main part of an electric furnace having an auxiliary combustion section structure according to the present invention.

FIG. 2 is a partial side sectional view showing a conventional electric furnace.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electric furnace 2 Side burner 3 Furnace wall 6 Burner cooling box 8 Upper water cooling panel 12 Bounce part 13 Space part

Claims (4)

[Claims] 1. A side burner (2) provided on a furnace wall (3).
In an auxiliary furnace structure of an electric furnace in which auxiliary combustion is performed in the furnace, a wall position above the side burner (2)
An auxiliary furnace structure for an electric furnace, wherein a rebound portion (12) for repelling a falling scrap in a direction away from the side burner (2) is provided so as to protrude into the furnace. 2. The auxiliary part of an electric furnace according to claim 1, wherein said bounce part is formed by an upper water cooling panel disposed above said side burner. Construction. 3. A space portion (13) for securing an air-fuel mixture space in the front area of the burner has a projection amount equivalent to that of the rebound portion (12) between the upper portion and the lower portion of the rebound portion (12) and the side burner (2). 3. A structure according to claim 1 or claim 2, wherein the structure is provided with a support. 4. An auxiliary furnace according to claim 3, wherein the space (13) is formed by a burner cooling box (6) surrounding a mounting portion of the side burner (2). Construction.