JP2001321926A - Method for discharging slag and its device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To quickly and easily discharge hard slag which floats on molten metal in a ladle and is cooled and hardened, to out side of the ladle. SOLUTION: A slag dipping vessel 10 is surrounded with a bottom plate 11, both side plates 12, 12 and a back plate 13, and has an opening part 14 at the front part side confronting the back plate 13. This dipping vessel 10 is immersed in the slag S in the ladle L under state of inclining by raising the opening part 14, and after making the slag flow into the dipping vessel 10 from the opening part 14, the dig-up vessel 10 is raised and carried away.

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 discharging refining slag flowing out to a ladle together with the molten metal when the molten metal is discharged from the refining furnace.

[0002]

2. Description of the Related Art When refining a molten metal in a refining furnace, slag generated from the solvent and oxide used in the refining is generated in the furnace. Then, a part of the slag flows out of the refining furnace to the ladle and floats on the molten steel in the ladle to be collected.
This slag has many adverse effects. For example, the alloy component contained in the molten metal reacts with oxygen in the slag to reduce the alloy component, the component goes out of a target range, and it becomes necessary to add an additional alloy. Become.

Further, when a gas is blown into a ladle to stir the molten metal to float oxides, ie, inclusions, contained in the molten metal, the gas causes a boundary between the molten metal and the slag. The surface is disturbed and slag is entangled in the opposite direction, and the number of inclusions increases. In addition, the components in the slag in the ladle may return to the molten metal on the contrary. For example, in steel refining, P (phosphorus)
Is concentrated in the slag, but the P (phosphorus) phenomenon in which the P (phosphorus) returns to the molten metal in the ladle occurs. in this way,
Since the slag in the ladle has an adverse effect, it must be discharged from the ladle, and it is necessary to discharge the slag quickly in order to avoid oxidization and recovery of the alloy components.

Conventional techniques for discharging a large amount of slag in a ladle include (1) a vacuum suction method and (2) a siphon type suction method. First, the vacuum suction method (1) will be described. When the slag is discharged from the ladle by vacuum suction, the surface temperature of the slag usually drops, the slag solidifies and becomes plate-like, and the plate-like slag does not enter the nozzle. Can not be discharged outside the ladle. Also, at the beginning of the suction operation, even if the properties of the slag are soft and easy to suck, the suction nozzle is located on the top of the slag,
The distance is set to about 100 mm, and suction is performed at 100 kg per minute, so the amount of slag is large when the capacity of the ladle is large, and it takes a long time to discharge it out of the ladle, and the passage of time At the same time, the temperature of the slag decreases, and slag solidifies in the nozzle, making it impossible to discharge.

Next, a description will be given of the siphon type suction method (2). In this method, the tip of the discharge nozzle is inserted into the slag, and the slag is discharged. As in the case of the above-described vacuum suction, the quality of the discharge depends on the properties of the slag. When the slag is hardened, air enters the nozzle and cannot be continuously discharged. Further, in the siphon-type suction method, unlike the vacuum suction method, no suction force is introduced from the outside. Therefore, if the discharge is performed for a long time, the slag is solidified in the nozzle, and the nozzle is clogged, and the discharge cannot be performed. In this way, in any of the conventional methods, solidified and plate-shaped slag can be smoothly discharged in large quantities from the ladle,
It was impossible.

[0006]

The problem to be solved by the present invention is to discharge slag from a ladle melt.
(1) To quickly discharge a large amount of slag out of the ladle;
And (2) discharging the solidified and plate-shaped slag out of the ladle smoothly.

[0007]

A slag discharging method according to the present invention for solving the above-mentioned problems is characterized in that an opening is formed at a front portion surrounded by at least a bottom plate, both side plates and a rear plate, and facing the rear plate. With the pumping vessel having the front plate of the bottom plate raised from the rear part and inclined, the open port is immersed in the slag, and the slag is allowed to flow into the pump container from the open port. It is characterized by being lifted and carried out.

Further, the slag discharger of the present invention is surrounded by at least a bottom plate, both side plates and a rear plate, has an opening at a front portion facing the rear plate, and is provided at two places before and after the both side plates. A lifting container having an engaging portion, and a lifting / lowering device for lifting / lowering the lifting container, wherein the lifting / lowering device is independently moved up and down, and the two lifting devices are moved horizontally. And a pair of hanging strips is attached to each of the two lifting devices,
Further, an engaging portion for engaging with the locking portion is attached to a lower end of the pair of hanging strips.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a slag discharging method and apparatus according to the present invention will be described in detail with reference to the drawings. FIG. 1 is a perspective view of a pumping container 10 for storing slag floating on a molten metal. The pumping container 10 includes a bottom plate 11 and a side plate 12,
12 and the rear plate 13, and the rear plate 1
The front part facing 3 is opened to form an opening 14 for slag inflow. The bottom plate 11, the side plates 12, 12 and the rear plate 13 are made of an iron plate having a thickness of about 60 mm, and are provided at two places before and after the outer surfaces of the side plates 12, 12 (a total of four places).
The locking part 1 used when suspending the pumping container 10
5 is attached. If necessary, the pumping vessel 10 may be provided with a top plate (not shown) at a position facing the bottom plate 11, and various coatings may be applied to the surface of the iron plate to obtain erosion resistance and slag peelability. Processing may be performed.

FIG. 2 is a side view of an elevating / lowering transport device 20 for tilting, raising / lowering, and transporting the pumping container 10, and FIG. 3 is a front view taken along line YY of FIG. The lifting / lowering device 20 includes lifting devices 21 and 22 and a transport device 23. The transport device 23 is, for example, a crane, and can move in a two-dimensional direction in a horizontal plane. Elevating devices 21 and 22 mounted and installed on a transport device 23 include a pair of right and left ropes 24 and 24 made of chains and wire ropes (FIG. 3,
) And 25, 25 (only the near side is shown).

At the lower ends of the cords 24 and 25, engaging portions 26 and 27 formed of C hooks are connected.
And 27 are engaged with locking portions 15, 15 provided on the outer surface of the side plates 12, 12 of the pumping container 10, so that the pumping container 10
Hanging. The lifting devices 21 and 22 have the function of operating independently, and the lifting device 21 can raise and lower the front part 10a of the pumping container, and the lifting device 22 can raise and lower the rear part 10b of the pumping container. For example, when only the cable 25 is lowered by the elevating device 22, the pumping container 10 is inclined by lowering its rear portion 10b.

Next, the actual slag discharging operation will be described. First, the slag S in the ladle L shown in FIG. 2 will be described. The temperature of the slag S floating on the melt Y decreases with time, and the slag S has a hardened slag layer SL whose surface has solidified. The slag layer SH is divided into two parts.

The operation procedure of slag discharge is as follows. (1) As shown in FIG. 2, the lifting container 22 is transported by the lifting / lowering transport device 20, moved to a position above the ladle L, and only the lifting / lowering device 22 is used to lower and tilt the rear portion 10b of the lifting container. Lower slightly. At this time, the lifting device 21
Is kept constant, and the front part 10a of the pumping container is placed in an upward state.

(2) In a state where the pumping container 10 is inclined,
The lifting devices 21 and 22 are operated at the same time to
The whole is lowered onto the slag S. Since the entire pumping container 10 is made of a thick iron plate and is heavy, it breaks the hard slag layer SL and enters the slag. (3) When the pumping container 10 is further lowered, the pumping container 1
The open port 14 in front of 0 reaches the soft slag layer SH which is not solidified in contact with the molten metal Y. Then, the opening 14
The hard slag layer SL and the soft slag layer SH start to flow into the pumping container 10 in large quantities.

(4) In the state of the above (3), the lifting devices 21 and 22 are stopped and held at that position until the flow of the slag into the pumping container 10 is completed. (5) When the inflow of the slag S into the pumping container 10 is completed, the lifting devices 21 and 22 are simultaneously operated to raise the pumping container 10 holding the slag S. (6) Next, as shown in FIG. 4, the pumping container 10 is transported by the transporting device 20 to a position above the slag discharge pot P, and the elevating devices 21 and 22 are simultaneously operated to position the pumping container 10 by a virtual line. Down to Then, the lifting device 22
When the rear portion 10b of the pumping container is raised at a high speed by operating only the slag S, the slag S can be discarded from the opening 14 to the discharge pot P. (7) The above (1) to (6) can be repeated several times to discharge a large amount of slag. In the above description, the example of discharging the slag in the ladle has been described. However, the present invention can also be applied to discharging the slag in the casting mold or the tundish.

[0016]

According to the conventional method, since a large amount of slag is discharged by the nozzle, the solidified slag cannot be discharged smoothly from the ladle. In the present invention, the slag pumping container is submerged in the slag in a state where the opening of the slag is raised and inclined so that the pumping container breaks the hardened slag surface layer, and the slag flows into the pumping container from the opening. Can be accommodated. As a result, a large amount of slag can be quickly stored and discharged in the pumping container.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a pumping container.

FIG. 2 is a side view (partially sectional view) of the lifting and lowering device.

FIG. 3 is a front view taken along line YY of FIG. 2;

FIG. 4 is a side view (partially sectional view) illustrating an operation of discharging slag to a discharge pot.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Slag pumping container 10a ... Front part of a pumping container 10b ... Rear part of a pumping container 11 ... Bottom plate 12 ... Side plate 13 ... Rear plate 14 ... Opening opening 15 ... Locking part 20 ... Elevating transport device 21 ... Elevating device 22 ... Lifting device 23 ... Transportation device 24 ... Hanging ridge 25 ... Hanging ridge 26 ... Engagement part 27 ... Engagement part S ... Slag SL ... Hard slag layer SH ... Soft slag layer L ... Ladle P ... Slag discharge pot

Claims (2)

[Claims] 1. A pumping container which is surrounded by at least a bottom plate, both side plates and a rear plate and has an opening at a front portion facing the rear plate, inclines by raising the front portion of the bottom plate from the rear portion. A slag is immersed in the slag in a state where the slag flows into the pumping container through the opening, and then the slag is lifted and carried out. 2. A pumping container which is surrounded by at least a bottom plate, both side plates, and a rear plate, has an opening at a front portion facing the rear plate, and has a locking portion at two positions before and after the both side plates. ,
The lifting and lowering transporting device is configured to lift and lower the lifting container, and the lifting and lowering transporting device includes two lifting and lowering devices that independently move up and down, and a transporting device that moves the two lifting and lowering devices in a horizontal direction. A slag discharge device, wherein a pair of hanging strips is attached to each of the lifting devices, and further, an engagement portion that engages with the locking portion is attached to a lower end of the pair of hanging strips.