JP2008121958A - Slag solidification system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a slag solidification system having excellent treating ability in a small space. <P>SOLUTION: The slag solidification system for solidifying slag discharged from an electric furnace 2 comprises a tilting device 6 tilting the electric furnace 2 to discharge slag from a slag discharge port 4 of the electric furnace 2; a plurality of molds 8 each having a bottom wall and a side wall; a slag carrying-discharging device carrying out a carry-in process for moving the empty mold 8 out of the molds 8 into a slag discharge position below the slag discharge port 4, a carry-out process for moving the mold 8 which has received the slag from the slag discharge position to a cooling position, and a slag discharge process for discharging solidified slag from the mold 8 in the cooling position; and a control device for controlling the tilting device 6 to regulate the thickness of slag in the mold 8 in a range from 10 mm to 300 mm. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a slag solidification system, and more particularly to a slag solidification system that solidifies slag discharged from an electric furnace.

Electric furnaces are used to manufacture steel products such as special steel, and melt raw materials into molten steel. A steelmaking material is also introduced into the electric furnace together with raw materials, and a slag layer is formed on the surface of the molten steel. Conventionally, by tilting the electric furnace, the slag is discharged from the electric furnace to the slag pot separately from the molten steel, and the discharged slag is cooled in the slag pot (for example, see Patent Document 1).
JP-A-6-323759

However, since the slag pot is deep, it takes 10 hours or more for the temperature of the slag to sufficiently decrease in the slag pot. If you leave a huge slag pot for more than 10 hours, time and space are wasted. Moreover, when the operation rate of the electric furnace becomes high, the processing capacity of slag cannot keep up.
Further, when the obtained slag coagulum is crushed for reuse or the like, since the coagulum is large, the load on the crusher is large.

  The present invention has been made based on the above-described circumstances, and an object of the present invention is to provide a slag solidification system having an excellent processing capacity in a small space.

  According to the present invention, in the slag solidification system that solidifies the slag discharged from the electric furnace, the tilting device that tilts the electric furnace and discharges the slag from the outlet of the electric furnace, the bottom wall and the side wall are provided. A plurality of molds each having a casting process for moving an empty mold among the casting molds to a loading position below the loading port, and a loading process for moving the mold receiving the slag from the loading position to the cooling position And a conveying and discharging device that executes a discharging process for discharging the solidified product of the slag from the mold at the cooling position, and the tilting device to control the thickness of the slag in the mold from 10 mm to 300 mm A slag solidification system comprising a control device that regulates within a range of (1) is provided.

Preferably, the mold has a height of 500 mm or less.
Preferably, the control device includes a measuring device that detects a mass of the mold at the protruding position, and controls the tilting device based on a detection result of the measuring device.
Preferably, the system includes a stationary support for supporting the mold at the output position, and an immobile cooling disposed near the support for the output and supporting the mold at the cooling position. And a transport carriage that moves between the vicinity of the support for support and the vicinity of the support for cooling, and is attached to the transport carriage. And an arm that transfers the mold to and from the support.

  Preferably, the system further includes a blower for air-cooling the mold in the cooling position (Claim 5).

In the slag solidification system according to the first aspect of the present invention, the heat of the slag in the mold is quickly released by regulating the thickness of the slag in the mold to 300 mm or less. For this reason, the slag in the mold quickly solidifies, and the solidified product of the slag is immediately discharged from the mold. As a result, this slag solidification system is capable of solidifying a large amount of slag in a short time and has a high throughput.
Further, in this slag solidification system, the slag quickly solidifies in the mold, and the solidified product of the slag is immediately discharged from the mold, and the empty mold again receives the slag from the electric furnace. For this reason, even when a large amount of slag is processed, the total number of molds may be small, and it is not necessary to prepare a vast space for accommodating the molds. As a result, this slag solidification system is installed in a small space.

Furthermore, according to this slag solidification system, when the thickness of the slag solidified material is in the range of 300 mm or less, the load on the crusher is small when the slag solidified material is crushed for reuse or the like.
According to the slag solidification system of the second aspect, since the mold height is 500 mm or less, the system height becomes lower if the molds are arranged side by side. Moreover, if the molds are arranged one above the other, the width or depth of the system becomes shorter.

According to the slag solidification system of claim 3, the thickness of the slag in the mold can be easily reduced to 300 mm or less when the slag is discharged from the electric furnace to the mold by controlling the tilting device based on the mass of the mold. It is reliably regulated by the configuration. Even if the mold is shallow, the slag can be reliably prevented from overflowing from the mold with a simple configuration.
According to the slag solidification system of claim 4, since the tapping support is immobile, a part of the slag discharged from the electric furnace jumps and scatters on the casting mold and adheres to the tapping support. , The output support will not break down. For this reason, this slag solidification system is excellent in reliability.

  In the slag solidification system according to the fifth aspect, the mold in the cooling position is cooled by air from the blower, so that the slag in the mold solidifies more rapidly. Also, as a result, this slag solidification system has a higher throughput. On the other hand, since this slag solidification system does not use water for cooling the slag, a steam explosion is prevented and it is safe.

1 and 2 show a slag solidification system according to an embodiment of the present invention.
The electric furnace 2 is used, for example, for steel making such as special steel, and melts raw materials to make molten steel. The electric furnace 2 is fed with steelmaking material together with the raw materials of steel, and a slag layer is formed on the surface of the molten steel. This slag is a slag rich in FeO component, and is discharged from the electric furnace 2 separately from the molten steel. The slag solidification system solidifies the slag that has been extracted, and the resulting solidified slag is processed into a heat-resistant material or the like and reused.

  The electric furnace 2 has a furnace main body, and has an outlet 4 for discharging slag on the side of the furnace main body. The electric furnace 2 is supported to be tiltable, and tilts from a horizontal posture by expanding and contracting a hydraulic cylinder 6 as a tilting device. When the electric furnace 2 is tilted, the slag inside the furnace body flows out from the tap hole 4 and hangs down below the tap hole 4. The electric furnace 2 may be a direct current type or an alternating current type.

  The slag solidification system has, for example, four molds 8a, 8b, 8c and 8d, and each mold 8 has a square dish shape (bat shape). As shown in FIG. 3, the mold 8 has a bottom wall and a side wall, and an upper surface is open. Preferably, the height H of the mold 8 is 500 mm or less. The engaging member 10 is attached to the bottom of the mold 8. The height H of the mold 8 is a height that does not include the engaging member 10.

  Referring again to FIG. 1, the slag solidification system has a tapping support 12 for supporting one mold 8 below the tapping opening 4 of the electric furnace 2. The protruding support 12 is a stationary frame that does not have a movable part, and is composed of a plurality of columns and a plurality of beams fixed to the columns. As shown enlarged in FIG. 4, the beam includes four cantilever beams 14. These cantilevers 14 are fixed to columns so as to correspond to the four corners of the mold 8, and a load cell 16 is fixed to the tip of each cantilever 14.

  The load cell 16 abuts on the bottom surface of the mold 8 without interfering with the engaging member 10, and the mold 8 is supported via the load cell 16. Further, the load cell 16 can measure not only the mass of the empty mold 8 but also the mass of the mold 8 that has received the slag, and the amount of slag (the amount of output) received by the mold 8 can be obtained from the change in mass. The output amount is input to the control device 18, and the control device 18 controls the operation of the hydraulic supply source 20 that supplies hydraulic pressure to the hydraulic cylinder 6 based on the output amount. That is, the control device 18 regulates the amount of protrusion for each mold 8 so that the thickness of the slag in the mold 8 is in the range of 10 mm to 300 mm, preferably in the range of 50 mm to 150 mm. In other words, as shown in FIG. 5, the amount T of the solidified product of the slag cooled in the mold 8 is in the range of 10 mm to 300 mm, preferably in the range of 50 mm to 150 mm. Is controlled.

  Referring again to FIG. 1, a cooling support 22 is arranged next to the output support 12, and the cooling support 22 is also a frame composed of a plurality of columns and a plurality of beams fixed to the columns. Is the body. A part of the column of the support 22 for cooling is the same as a part of the column of the support 12 for output, and in the support 22 for cooling, the tip of the cantilever of the beams is engaged. The mold 8 is supported by contacting the bottom surface of the mold 8 without interfering with the member 10. The cooling support 22 has four cooling positions in two vertical rows and two horizontal rows, and can accommodate up to four molds 8.

A blower 24 is installed next to the cooling support 22. The blower 24 generates a wind toward the cooling support 22, and the mold 8 supported on the cooling support 22 is cooled by the wind.
Next to the blower 24, a slag pan 26 is disposed so as to be able to be conveyed, and the slag pan 26 receives a solidified product of slag discharged (discharged) from the mold 8. The tapping support 12, the cooling support 22, the blower 24, and the slag pan 26 are arranged in series in front of the tapping opening 4 of the electric furnace 2 when viewed in the horizontal direction. In other words, when viewed in the horizontal direction, an output area, a cooling area, and a discharge area are partitioned in series in front of the output port 4 of the electric furnace 2.
Referring to FIG. 2, two linear rails 28 are laid parallel to each other along the output support 12, the cooling support 22, the blower 24, and the slag pan 26. A transport cart 30 for transporting 8 is arranged. The transport carriage 30 can travel on the rail 28 and has a cooling position of the support 12 for cooling and the cooling support 22 and a stop position on the side of the slag pan 26. That is, a transport area for transporting the mold 8 is provided beside the exit area, the cooling area, and the discharge area.

  As shown in FIG. 6, a prop 32 is movably set up on the transport carriage 30, and the prop 32 can reciprocate in the lateral direction toward the support 12 for cooling, the support 22 for cooling, or the slag pan 26 side. It is. Two arms 34 parallel to each other are attached to the support column 32, and the arms 34 can move up and down along the support column 32. The transfer of the mold 8 is performed between the transport carriage 30 and the support 12 for cooling and the support 22 for cooling by using the reciprocating motion of the support column 32 and the vertical motion of the arm 34.

Further, the arm 34 can be tilted with respect to the support column 32, and the sludge solid in the mold 8 is discharged toward the slag pan 26 by tilting the arm 34 on the slag pan 26. Even if the arm 34 tilts, the mold 8 does not fall from the arm 34 because the arm 34 and the engaging member 10 are engaged.
Hereinafter, although the operation method (usage method) of the slag solidification system described above will be described, the tapping, cooling, and discharging processes are repeatedly performed using a plurality of molds 8. For this reason, the state shown in FIG. 1 and Table 1 (first intermediate state) will be described, and for convenience, the cooling positions of the mold 8 and the cooling support 22 will be given first to fourth numbers.

  As shown in FIG. 7, the hydraulic cylinder 6 is operated so that the electric furnace 2 is inclined from the first intermediate state, and the slag is discharged from the outlet 4 of the electric furnace 2 to the first mold 8a. Is started (S10). After the mass of the first mold 8a reaches a predetermined value, the hydraulic cylinder 6 is operated so that the electric furnace 2 is in the original horizontal state, and the slag discharge from the outlet 4 of the electric furnace 2 is completed ( S40).

On the other hand, simultaneously with the start of slag discharge from the electric furnace 2, the transport carriage 30 transports the second mold 8b to the discharge position. Thereafter, the arm 34 of the transport carriage 30 is tilted, so that the solidified slag in the second mold 8b falls from the second mold 8b into the slag pan 26 (S20). The empty second mold 8b is transported to the second cooling position by the transport carriage 30 (S30).
Thereafter, the transport cart 30 moves to the side of the output position, but the output to the first mold 8a is completed before the transport cart 30 arrives at the side of the output position. The transport carriage 30 clamps (holds) the first mold 8a that has received the slag, and transports (unloads) it to the first cooling position (S50). Thereafter, the transport carriage 30 clamps the empty second mold 8b at the second cooling position and transports (loads) it to the unloading position (S60). Then, the transport carriage 30 moves to the side of the third cooling position and clamps the third mold 8c (S70).

  Thus, from the intermediate state of Table 1, one cycle (first cycle) including the exiting process to the first mold 8a and the discharging process from the second mold 8b is completed, and the state of Table 2 (second intermediate) State).

  The cycle (second cycle) performed next to the second intermediate state is the same as the first cycle except that the number of the mold 8 is different, and the step of feeding to the second mold 8b and the third mold 8c. The next cycle (the third cycle) including the discharging process from No. 3 includes the discharging process to the third mold 8c and the discharging process from the fourth mold 8d. The further next cycle (fourth cycle) includes an exiting process to the fourth mold 8d and an exhausting process from the first mold 8a. When this fourth cycle is completed, the first intermediate state shown in Table 1 is obtained. Thereafter, the first to fourth cycles are repeatedly performed.

In the operation method described above, the slag received by the first mold 8a is cooled at the first cooling position through the second cycle and the third cycle until the middle of the fourth cycle, thereby solidifying. The solidified slag in the first mold 8a is discharged to the slag pan 26 during the fourth cycle, and then the empty first mold 8a is air-cooled at the first cooling position.
That is, as shown in FIG. 8, in the case of the first mold 8a, during the period from the start of the first cycle to the end of the fourth cycle, the output, the cooling of the received slag, the discharge, and the empty The first mold 8a itself is sequentially cooled in the state. The same applies to the other molds 8b, 8c, and 8d except that the acceptance of the slag is shifted by one cycle.

The operations of the transport carriage 30, the support column 32, the arm 34, and the hydraulic cylinder 6 as the tilting device are all controlled by the control device 18.
In the slag solidification system described above, the heat of the slag in the mold 8 is quickly released by regulating the thickness of the slag in the mold 8 to 300 mm or less. For this reason, the slag in the mold 8 is quickly solidified, and the solidified slag is immediately discharged from the mold 8. As a result, this slag solidification system is capable of solidifying a large amount of slag in a short time and has a high throughput.

  Further, in this slag solidification system, the slag solidifies quickly in the mold 8, and the solidified product of the slag is immediately discharged from the mold 8, and the vacant mold 8 receives the slag from the electric furnace 2 again. For this reason, even when a large amount of slag is processed, the total number of the molds 8 may be small, and it is not necessary to prepare a vast space for accommodating the molds 8. As a result, this slag solidification system is installed in a small space.

Furthermore, according to this slag solidification system, when the thickness of the solidified slag is 300 mm or less, the load on the crusher is small when the solidified slag is crushed for reuse.
According to the slag solidification system described above, since the height H of the mold 8 is 500 mm or less, the height of the system becomes lower if the molds 8 are arranged side by side. Further, if the molds 8 are arranged one above the other, the width or depth of the system becomes shorter.

According to the slag solidification system described above, when the slag is discharged from the electric furnace 2 to the mold 8 by controlling the hydraulic cylinder 6 based on the mass of the mold 8, the thickness of the slag in the mold 8 is 300 mm or less. It is reliably regulated with a simple configuration. Further, even if the depth of the mold 8 is shallow, the slag can be reliably prevented from overflowing from the mold 8 with a simple configuration.
According to the slag solidification system described above, since the tapping support 12 is stationary, a part of the slag discharged from the electric furnace 2 jumps and scatters in the mold 8 and adheres to the tapping support 12. Even so, the tapping support 12 does not break down. For this reason, this slag solidification system is excellent in reliability. In order to prevent a failure of the transport carriage 30, it is preferable that the transport carriage 30 be next to the cooling area or the discharge area during the extraction from the electric furnace 2.

  In the above-described slag solidification system, the mold 8 in the cooling position is forcibly cooled by air blown from the blower 24, so that the slag in the mold 8 solidifies more rapidly. Also, as a result, this slag solidification system has a higher throughput.

Examples 1 and 2 and Comparative Example 1
As Examples 1 and 2, slag having a temperature of 1600 ° C. was poured into the mold 8 (length 1900 mm × width 1100 mm × height 300 mm) so that the thickness of the solidified slag became the value shown in Table 1. The cooling time until the surface temperature of (slag solidified product) reached 1000 ° C. was measured. The results are shown in Table 1.
As Comparative Example 1, slag at a temperature of 1600 ° C. was introduced into a slag pan (length 1950 mm x width 1600 mm x height 1400 mm) so that the thickness of the slag coagulum became 500 mm, and the surface temperature of the slag (slag coagulum) The cooling time until the temperature reached 1000 ° C. was measured. The results are shown in Table 1.

  From Table 3, it can be seen that in Examples 1 and 2 in which the thickness of the solidified slag is 300 mm or less, the cooling time is remarkably shorter than in Comparative Example 1 in which the thickness exceeds 300 mm. The cooling time of Example 1 and 2 is 3000 seconds (50 minutes) or less, and if it is this cooling time, the slag discharged | emitted from the electric furnace in operation can fully be processed.

The present invention is not limited to the above-described embodiment, and various modifications are possible. For example, the number of the molds 8 may be plural, but three to ensure sufficient processing capability. The above is preferable. Considering the balance between space and processing capacity, 4 is most preferable.
In one embodiment, although forcedly cooled by the blower 24, the heat may be naturally radiated without providing the blower 24. Or although slag may be forcedly cooled with mist-like water (mist), in order to prevent a steam explosion and to ensure safety, ventilation cooling is preferable.

  In one embodiment, the engaging member 10 is attached to the bottom surface of the mold 8, but the engaging member may be formed on the arm 34 of the transport carriage 30. That is, the configuration of the engaging member is not particularly limited as long as the solidified slag can be taken out from the mold 8. In addition, the solidified material is discharged from the mold 8 by tilting the arm 34 of the transport carriage 30, but the means for discharging the solidified material from the mold 8 is not particularly limited. For example, a separate evacuation device that tilts the mold 8 to discharge the solidified material may be provided, and the mold 8 may be carried to the evacuation device by the transport carriage 30.

In one embodiment, the support column 32 can be reciprocated in the lateral direction, but the means for transferring the mold 8 between the transport carriage 30 and the feed support 12 or the cooling support 22 is not particularly limited. For example, an extendable arm may be attached to the fixed column.
In one embodiment, although the amount of output is detected using the load cell 16, the means for detecting the thickness of the slag in the mold 8 is not particularly limited.

It is a side view showing a schematic structure of a slag solidification system of one embodiment. FIG. 2 is a plan view of the system of FIG. 1. It is sectional drawing of the casting_mold | template applied to the system of FIG. FIG. 2 is an enlarged view of the vicinity of the support for the output in the system of FIG. 1. It is a perspective view of the solidified substance of slag obtained using the casting_mold | template of FIG. It is an enlarged view of the slag pan vicinity in the system of FIG. It is a flowchart for demonstrating the operating method of the system of FIG. It is a chart for demonstrating the operating method of the system of FIG. 1 according to the casting_mold | template.

Explanation of symbols

2 Electric furnace 4 Outlet 6 Hydraulic cylinder (tilting device)
8 Mold

Claims (5)

In the slag solidification system that solidifies the slag discharged from the electric furnace,
A tilting device that tilts the electric furnace and discharges the slag from the outlet of the electric furnace;
A plurality of molds each having a bottom wall and side walls;
A carrying-in process of moving an empty mold among the molds to an unloading position below the unloading port, an unloading process of moving the mold that has received the slag from the unloading position to the cooling position, and the cooling position A conveying and discharging device for executing a discharging process for discharging the solidified slag from the mold;
A slag solidification system comprising: a control device that controls the tilting device to regulate the thickness of the slag in the mold within a range of 10 mm to 300 mm.   The slag solidification system according to claim 1, wherein the mold has a height of 500 mm or less.   The said control apparatus contains the measuring device which detects the mass of the said casting_mold | template of the said extraction position, and controls the said tilting apparatus based on the detection result of the said measuring device. Slag solidification system. An immobilizing support for the output that supports the mold at the output position;
A stationary cooling support that is disposed in the vicinity of the protruding support and supports the mold in the cooling position;
The transfer device
A transport carriage that moves between the vicinity of the support for the feed and the vicinity of the support for cooling;
The slag solidification system according to any one of claims 1 to 3, further comprising an arm attached to the transport carriage and configured to transfer the mold between the transport carriage and the support.   The slag solidification system according to any one of claims 1 to 4, further comprising a blower for air-cooling the mold in the cooling position.

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