JPH11264009A - Prevention / removal of metal sticking at converter mouth - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To not only remove bullion adhering to a furnace mouth of a converter, but also to prevent bullion from adhering to a furnace mouth. SOLUTION: A plurality of gas injection nozzles 5 are disposed at intervals on a circumference in a gap formed by a furnace port 2 of a converter 1 and an upper skirt 4 so as to be adjustable in position. During blowing, nitrogen gas is blown out from the gas injection nozzle 5 to prevent the metal 3 from adhering near the furnace port 2, and after blowing the converter 1, oxygen gas is blown from the gas injection nozzle 5. Eruption, furnace mouth 2
Is melted and removed with good workability.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for preventing and removing metal ingots of a converter furnace mouth, which can prevent metal from sticking in addition to removing metal that has adhered to the furnace furnace mouth. It is about.

[0002]

2. Description of the Related Art Generally, as shown in FIG. 5, in operation of a converter 1, oxygen gas is injected from an oxygen lance 32 suspended in a furnace through a skirt 4 to blow molten metal 31 in the furnace. . The molten metal 31 in the furnace is scattered by slopping or spitting caused by blowing, solidifies in the furnace port 2, and adheres as the metal 3. If the metal 3 grows gradually toward the inside of the furnace port 2 to reduce the inside diameter of the furnace port, it becomes difficult to insert the oxygen lance 32 and charge the auxiliary material, thereby hindering the operation of the converter. Therefore, conventionally, when the amount of applied metal becomes large, as shown in FIG. 6, the converter 1 is turned down and the rotary cutter 36 is moved from below to the metal 3 attached to the furnace opening 2. It has been proposed to delete (Japanese Patent Publication No. 63-12922)
Reference).

Further, as shown in FIG.
A metal removal lance 39 is attached to a carriage 38 which is set up and down freely on a vertical guide 37 arranged above the metal guide, and oxygen gas is injected from the metal removal lance 39 to attach metal ingot to the furnace port 2 of the converter 1. No. 3 is disclosed (see JP-A-6-65729). Further, as shown in FIG. 8, disclosed is a method in which oxygen gas is injected from a metal removal lance 39 disposed in front of the converter 1 in which the metal 3 attached to the furnace opening 2 is turned sideways to dissolve and remove the metal. (See JP-A-64-87711).

[0004]

[Problems to be solved by the invention]
In the prior art proposed in JP-A-63-12922, intense vibration when a rotary cutter is pressed and cut and removed against a metal sticking to a furnace mouth of a converter is transmitted to the converter, and the furnace body and the furnace wall are removed. It has a bad influence on refractory equipment and causes troubles in the furnace body, so the rotary cutter cannot fully remove its ability.
Further, the conventional technique disclosed in Japanese Patent Application Laid-Open No. 6-65729 has a drawback that the metal inside the furnace mouth can be removed, but the metal outside the furnace mouth cannot be removed.

Further, in the prior art disclosed in Japanese Patent Application Laid-Open No. 64-87711, oxygen gas injected from a metal removal lance is injected toward the furnace opening of the converter, so that not only the adhered metal but also There is also a problem that the refractory is strongly injected into the furnace mouth refractory, which easily causes the refractory to melt and shortens the life of the refractory. As described above, the conventional technology basically aims only to remove the sliver adhering to the furnace mouth of the converter, and does not intend to prevent the sliver from being generated at the furnace mouth. .

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems of the prior art, the present invention not only removes the sliver attached to the furnace mouth of the converter, but also prevents the sliver from attaching to the furnace mouth. It is an object of the present invention to provide a device for preventing and removing metal sticking of a converter furnace mouth.

[0007]

In order to achieve the above object, according to the present invention, there is provided a method of manufacturing a fuel cell system, comprising the steps of: An apparatus for preventing and removing metal sticking to a converter furnace mouth, comprising a plurality of gas injection nozzles arranged and an inert gas supply pipe and an oxidizing gas supply pipe connected to the gas injection nozzles in a switchable manner. .

According to a second aspect of the present invention, the gas injection nozzle is disposed so as to be adjustable in front and rear, left and right, and up and down directions.
It is a removal device. According to a third aspect of the present invention, the gas injection nozzle is disposed at a distal end of a plurality of branch gas supply pipes taken out at intervals on a circumference of a ring-shaped gas header surrounding an outer circumference of the skirt. The apparatus for preventing and removing adhesion of metal to a converter furnace mouth according to claim 1, characterized in that:

According to a fourth aspect of the present invention, the gas injection nozzle is of a Laval type, a straight type, a rapid expansion type or a slit type. It is a device for preventing and removing metal ingot. According to a fifth aspect of the present invention, a plurality of gas injection slit nozzles are arranged at intervals on a circumference of a furnace inner portion of an annular gas header member arranged around the entire upper end of the converter furnace port. An apparatus for preventing and removing adhesion of metal to a converter furnace port, wherein an inert gas supply pipe and an oxidizing gas supply pipe are switchably connected to an injection slit nozzle.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. In this embodiment, a case of a top-blowing converter will be described. However, the present invention can be applied to a top-blowing converter or a bottom-blowing converter. As shown in FIG. 1, a skirt 4 is arranged near and above a furnace port 2 of a converter 1, and a base metal 3 is adhered to a furnace wall refractory 30 near the furnace port 2. A plurality of gas injection nozzles 5 are arranged between the furnace port 2 and the skirt 4 at intervals in the circumferential direction of the furnace port 2. The number of the gas injection nozzles 5 is desirably selected so that the gas blown out from the nozzle tip can cover the entire circumferential area of the furnace port 2.

In order to supply gas to the gas injection nozzle 5,
An inert gas supply pipe 6 and an oxidizing gas supply pipe 7 are juxtaposed, and a gas supply pipe 8 that joins them is connected to a gas supply pipe 10 via a supply hose 9. A gas injection nozzle 5 is attached to the section. Opening / closing valves 11 and 12 are provided on the inert gas supply pipe 6 and the oxidizing gas supply pipe 7, respectively.
Is provided with a flow control valve 29. As the inert gas to be used, a relatively inexpensive nitrogen gas is suitable, but an argon gas may be used in some cases. Also,
As the oxidizing gas, oxygen gas is used, but it is not necessary to use expensive pure oxygen gas, and oxygen-enriched air having a high oxygen content can be used.

On the other hand, in order to adjust the position of the gas injection nozzle 5, a traverse vehicle 14 having a driving device 24 on a ceiling track 13 is provided above the converter 1 so as to be able to travel freely.
A rectangular guide post 15 is vertically provided at the lower part of the box. On the square guide post 15, an elevating carriage 16 is arranged so as to be able to move up and down. On a horizontal bracket 17 provided above and below the front surface of the elevating carriage 16, a nozzle support rod 18 is provided with an upper and lower bearing 19.
Is supported rotatably about the axis. The gas supply pipe 10 is supported in the middle of the gas supply pipe 10 by a nozzle holder 20 provided at the lower end of the nozzle support rod 18, and the gas injection nozzle 5 is connected to the tip of the gas supply pipe 10.

A piston rod 23 of a lifting cylinder 21 provided downward in the middle of the rectangular guide post 15 is connected to a bearing 22 provided on the back of the lifting carriage 16. In addition, a turning cylinder is mounted on a base 25 provided on the upper horizontal bracket 17.
26 is installed, and the piston rod 27 of the swing cylinder 26
Is connected to a lever 28 provided at the upper end of the nozzle support rod 18.

Before starting the blowing of the converter 1, the driving device 24
Drive the traversing car 14 forward along the ceiling track 13,
The gas injection nozzle 5 is moved closer to the converter 1. Lifting cylinder
21 is extended, the elevating carriage 16 is lowered together with the nozzle support rod 18 along the rectangular guide post 15, and the vertical direction of the gas injection nozzle 5 supported by the nozzle holder 20 provided at the lower end of the nozzle support rod 18 is raised. Positioning is performed, and it is inserted into a predetermined position between the furnace port 2 and the skirt 4. The swivel cylinder 26 is operated as required, and the swivel angle of the nozzle support rod 18 is adjusted via the lever 28 by the expansion and contraction of the piston rod 27, thereby changing the direction in which the gas injection nozzle 5 jets left and right.

Simultaneously with the start of the blowing of the converter 1, the opening / closing valve 11 provided in the inert gas supply pipe 6 is opened, and nitrogen gas, for example, nitrogen gas as an inert gas is supplied from the inert gas supply pipe 6 to the gas supply pipe 8. The gas is supplied to the gas injection nozzle 5 through the hose 9 and the gas supply pipe 10, and the nitrogen gas is injected from the gas injection nozzle 5 into the furnace through the gap between the furnace port 2 of the converter 1 and the skirt 4. As a result, the molten steel or molten slag scattered by the molten steel blowing in the converter 1 is blown back into the furnace, so that the furnace port 2 is blown.
To prevent the metal 3 from adhering to the metal.

By arranging the gas injection nozzle 5 so that the nitrogen gas injected from the gas injection nozzle 5 reaches over the entire gap between the furnace port 2 and the skirt 4, the nitrogen gas is discharged to the vicinity of the furnace port 2. Adhesion can be greatly reduced. Furnace port 2
The position of the gas injection nozzle 5 arranged in the gap between the skirt 4 and the skirt 4 can be freely adjusted by combining forward and backward movement of the transverse vehicle 14, lifting and lowering of the lifting carriage 16 and turning of the nozzle support rod 18 around the axial center. In addition, the amount of nitrogen gas injected from the gas injection nozzle 5 can be adjusted over a wide range by the flow control valve 29, and the adhesion of the metal 3 can be prevented flexibly over the entire furnace port 2.

The gas injection nozzle 5 has a well-known Laval type in order to change the gas flow rate, the spread angle θ, the injection amount, and the like in accordance with the scattering state such as slopping and spitting generated in the converter 1. A straight type, a rapid expansion type, a slit type, or the like can be appropriately selected, or a combination of different types can be used. When the blowing of the converter 1 is completed, the on-off valve 11 is closed to stop the nitrogen gas injection from the gas injection nozzle 5. After tilting the converter 1 and tapping and discharging, the gas injection nozzle 5 is positioned in the vicinity of the furnace port 2 in the same manner as above in such a manner that the gas injection nozzle 5 is positioned at the place where the metal 3 has adhered. I do. The on-off valve 12 provided on the oxidizing gas supply pipe 7 is opened, and oxygen gas is supplied from the oxidizing gas supply pipe 7 as an oxidizing gas through the gas supply pipe 8, the supply hose 9, and the gas supply pipe 10. The oxygen is supplied from the gas injection nozzle 5 toward the metal 3 attached to the furnace port 2 to melt and remove the metal 3. While the oxygen gas is being ejected, the position of the gas ejection nozzle 5 can be freely adjusted as described above, and the amount of the oxygen gas ejected is controlled by the flow control valve 29.
The metal 3 can be dissolved and removed efficiently.

When the apparatus for preventing and removing metal ingot at the converter furnace mouth of the present invention shown in FIG. 1 is used to melt medium to ultra-low carbon steel in an upper-bottom blow converter with a heat size of 250 t / ch, A plurality of gas injection nozzles (adjustable to a gas jet divergence angle of 90 ° or less) are set in the gap between the furnace port and the skirt in the circumferential direction, and the gas injection speed is set in the range of 50 to 100 Nm ³ / min. Nitrogen gas is blown out during blowing to prevent metal from sticking to the furnace opening. Then, after blowing the converter, oxygen gas was injected into the high-temperature metal adhering to the vicinity of the furnace port to dissolve and remove the metal. According to the present invention, assuming that the ingot removal frequency in the conventional case where only ingots are removed from the furnace opening is set to 1 as a reference index,
According to the present invention, the frequency of operation for removing the converter ingot can be greatly reduced to 0.1, and the productivity index of molten steel can be increased to 1.05.

In the above embodiment, one of the gas injection nozzles 5
Although the case where the position adjustment can be performed for each unit has been described,
It is also possible to group several gas injection nozzles in the circumferential direction of the furnace port 2 and adjust the position collectively for each group. The means for adjusting the forward / backward movement, up / down movement and left / right position is not limited to the above means, and other well-known means such as a rack and pinion mechanism can be appropriately used.

Another embodiment of the present invention will be described with reference to the drawings. As shown in FIG. 2, a ring-shaped gas header 34 surrounding the skirt 4 disposed above the furnace port 2 of the converter 1 is installed around the skirt 4, and an interval is provided from the circumference of the ring-shaped gas header 34. The gas injection nozzles 5 are respectively arranged at the distal ends of the plurality of branch gas supply pipes 35 taken out. In order to supply gas to the gas injection nozzle 5, an inert gas supply pipe 6 and an oxidizing gas supply pipe 7 are provided in parallel, and a gas supply pipe 8 which joins the inert gas supply pipe 6 and a gas supply pipe 9 is connected via a supply hose 9 and a gas supply pipe 10. Connected to the gas header 34. The gas injection nozzle 5 is attached to the tip of a plurality of branch gas supply pipes 35 taken out from the circumference of the ring-shaped gas header 34 at intervals.
Is attached. The inert gas supply pipe 6 and the oxidizing gas supply pipe 7 are provided with opening / closing valves 11 and 12, respectively, and the gas supply pipe 8 is provided with a flow control valve 29 in the case described above. The procedure and operation are the same as those described above except that the inert gas and the oxidizing gas are supplied via the ring-shaped gas header 34, so that the description is omitted.

In this case, the gas injection nozzle 5 disposed between the furnace port 2 and the skirt 4 cannot adjust the position of the gas injection nozzle 5 while injecting the inert gas or the oxidizing gas. The direction in which the metal 3 is scattered is almost fixed, and a place where the metal 3 of the furnace port 2 is likely to adhere can be specified. Therefore, by adjusting the arrangement position of the gas injection nozzle 5 in advance, it is possible to prevent the adhesion of the metal 3 by injecting the inert gas from the gas injection nozzle 5 and to prevent the metal 3 from being injected by the oxidizing gas injection.
Can be efficiently dissolved and removed. The position adjustment of the gas injection nozzle 5 can be performed by, for example, replacing the gas injection nozzle 5 and the branch gas supply pipe 35 having different specifications such as lengths when the converter 1 is stopped.

Further, as another embodiment, as shown in FIG. 3 and FIG. 4, an annular gas header 33 is placed over the entire upper end of the furnace port 2 of the converter 1, and the annular gas header 33 is installed.
A plurality of gas injection slit nozzles 33a are arranged on the upper surface of the inside of the furnace 33 in three rows in the radial direction and on the front side of the inside of the furnace at intervals in the circumferential direction. An inert gas supply pipe 6 and an oxidizing gas supply pipe 7 are juxtaposed to eject gas from the gas injection slit nozzle 33a. An annular gas header 33 is connected to the gas supply pipe 8 that joins the inert gas supply pipe 6 and the oxidizing gas supply pipe 7. I have. The inert gas supply pipe 6 and the oxidizing gas supply pipe 7 are provided with opening and closing valves 11 and 12, respectively, and the gas supply pipe 8 is provided with a flow control valve 29.

Simultaneously with the start of blowing of the converter 1, the opening / closing valve 11 disposed on the inert gas supply pipe 6 is opened, and the inert gas is supplied from the inert gas supply pipe 6 to the annular gas header 33 via the gas supply pipe 8. For example, a nitrogen gas is supplied as a gas, and a nitrogen gas is injected into the furnace through a gap between the furnace port 2 of the converter 1 and the skirt 4 from a gas injection slit nozzle 33a provided in the annular gas header 33. Thus, the droplets scattered by the molten steel blowing in the converter 1 can be blown back into the furnace, and the metal 3 can be prevented from adhering to the furnace port 2. Gas injection slit nozzle
The amount of nitrogen gas injected from the nozzle 33a can be adjusted over a wide range by the flow control valve 29, and the adhesion of the metal 3 can be prevented efficiently.

When the blowing of the converter 1 is completed, the on-off valve 11 is closed to stop the nitrogen gas injection from the gas injection slit nozzle 34. Then, after the furnace body is tilted and the steel is tapped and discharged, the open / close valve 12 provided in the oxidizing gas supply pipe 7 is opened, and the oxygen gas is supplied from the oxidizing gas supply pipe 7 to the gas supply pipe 8 as the oxidizing gas. The oxygen gas is supplied to the annular gas header 33 via the gas injection slit nozzle 33a, and oxygen gas is injected from the gas injection slit nozzle 33a to melt and remove the metal 3 attached to the furnace port 2. At this time, the amount of oxygen gas ejected can be adjusted by the flow control valve 29, so that the metal 3 can be efficiently dissolved and removed.

[0025]

As described above, according to the present invention,
A plurality of gas injection nozzles are arranged at intervals on a circumference in a gap formed by the converter furnace port and a skirt facing the upper side, or are arranged around the entire upper end of the converter furnace port. A plurality of gas injection slit nozzles are disposed at intervals on the circumference of the annular gas header inside the furnace. During blowing of the converter, an inert gas is blown out from the gas injection nozzle or gas injection slit nozzle to prevent metal from adhering near the furnace port. Alternatively, since the oxidizing gas is jetted from the gas jet slit nozzle to melt and remove the metal adhering to the vicinity of the furnace port, the operation rate of the converter can be improved.

[Brief description of the drawings]

FIG. 1 is a side view showing an apparatus for preventing and removing metal sticking of a converter furnace mouth according to the present invention.

FIG. 2 is a side view showing another apparatus for preventing and removing metal ingot at a converter furnace mouth according to the present invention.

FIG. 3 is a side view showing still another apparatus for preventing and removing metal sticking of a converter furnace mouth according to the present invention.

FIG. 4 is a sectional view showing the annular gas header according to FIG. 3;

FIG. 5 is a side view showing a state of ingot adhesion near a furnace opening in a conventional converter.

FIG. 6 is a side view showing a conventional rotary cutter for removing metal sticking to a converter furnace opening.

FIG. 7 is a side view showing a conventional metal removal lance for removing metal adhered to a converter furnace opening.

FIG. 8 is a side view showing another ingot removal lance for removing ingots attached to a converter mouth of a conventional converter.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Converter 2 Furnace opening 3 Ingot 4 Skirt 5 Gas injection nozzle 6 Inert gas supply pipe 7 Oxidizing gas supply pipe 8, 10 Gas supply pipe 9 Supply hose 11, 12 Opening / closing valve 13 Ceiling track 14 Crossing car 15 angle Die guide post 16 Elevating carriage 17 Horizontal bracket 18 Nozzle support rod 19, 22 Bearing 20 Nozzle holder 21 Elevating cylinder 24 Drive 25 Mount 26 Slewing cylinder 23, 27 Piston rod 28 Lever 29 Flow control valve 30 Furnace wall refractory 31 Molten metal 32 Oxygen lance 33 Annular gas header 33a Gas ejection slit nozzle 34 Ring-shaped gas header 35 Branch gas supply pipe 36 Rotary cutter 37 Vertical guide 38 Carriage 39 Metal removal lance

Claims (5)

[Claims] 1. A plurality of gas injection nozzles are arranged at intervals on a circumference formed in a gap formed by a converter furnace opening and a skirt facing the same, and an inert gas supply pipe and An apparatus for preventing and removing adhesion of metal to a converter furnace mouth, wherein an oxidizing gas supply pipe is switchably connected. 2. The apparatus for preventing and removing adhesion of metal to a converter furnace mouth according to claim 1, wherein said gas injection nozzle is arranged so as to be adjustable in front, rear, left, right and up and down. 3. The gas injection nozzle according to claim 1, wherein the gas injection nozzle is disposed at a distal end of a plurality of branch gas supply pipes taken out at intervals on a circumference of a ring-shaped gas header surrounding an outer circumference of the skirt. The apparatus for preventing and removing adhesion of metal to a converter furnace mouth according to claim 1. 4. The apparatus for preventing and removing adhesion of metal to a converter furnace mouth according to claim 1, wherein the gas injection nozzle is of a Laval type, a straight type, a rapid expansion type or a slit type. . 5. A plurality of gas injection slit nozzles are arranged at intervals on a circumference of a furnace inner portion of an annular gas header member disposed all around an upper end portion of a converter furnace port. An apparatus for preventing and removing adhesion of metal to a converter furnace mouth, wherein an inert gas supply pipe and an oxidizing gas supply pipe are connected in a switchable manner.