JP2002146412A - Trough for molten slag - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make the flowing-down position of molten slag constant regardless of discharge rate from a trough and to scarcely develop the clogging of a nozzle. SOLUTION: The trough 1 is used for discharge of the molten slag from the nozzle 4 by once receiving the molten slag 3. A nozzle housing part 1b, where the bottom surface 1a at the trough inner surface side is protruded into the trough 1 by recessing the outer surface of the trough 1 into the inner surface side, is formed in the bottom part 1a at the upstream side from the end surface at the discharging side of the trough 1. In the nozzle housing part 1b, plural nozzles 4 provided with the discharging holes 4a are arranged on one or orthogonal lines 6 in the flowing direction 5 of the molten slag 7 in the trough 1. In this way, the flowing-out position and rate of the molten slag are stabilized, and nozzles for water and compressed gas can be approached to the molten slag flowing position as much as possible, thus the variation of the treating condition can be reduced, and the quality and yield of the slag product can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a method for treating molten slag generated from an ironworks, for example, by subjecting the molten slag to a process such as water granulation and air blasting to reuse the molten slag once and quantitatively discharge the molten slag. Also, the present invention relates to a gutter for receiving a high-temperature molten material such as a molten metal from a container once in a field such as powder metallurgy and quantitatively discharging the molten metal in a molten state.

[0002]

2. Description of the Related Art In recent years, for example, molten slag from a blast furnace or a steelmaking furnace has been discharged from a furnace and then discharged through a gutter into a so-called dry pit, which is cooled, or once received in a pot and then separated. Transported to a slag treatment plant located in a suitable place, discharged and crushed and sized after slow cooling, crushed and cooled with a large amount of water near the furnace (water crushing), or dispersed and solidified with a large amount of gas. To make sand (blasting).

[0003] Among these, when performing treatment such as water granulation or air crushing, the stability of the molten slag at the time of outflow, the outflow position, the outflow speed and the like greatly affect the quality of the slag product to be produced. Stability and consistency are desired. In particular, if the outflow state does not draw a parabola, the positions of water granulation and wind breaking do not change, and the manufacturing conditions can be greatly improved. As a method, there is a method of flowing vertically from the hole nozzle, but the nozzle flowing out of the hole is used as the outflow portion structure of the molten slag due to problems such as adhesion of solidified matter, formation of a solidified film, and occurrence of clogging. Conventionally, for example, JP-A-6-24787, JP-A-54-106096
JP-A-59-44578, JP-A-5-11280
No. 5, Japanese Patent Application Laid-Open No. 5-31213, etc., often employ a structure in which the end of the gutter is opened or the flow is adjusted by a weir.

In such a structure in which the end of the gutter is opened or the flow is adjusted by a weir, the molten slag has a flowing shape in which a horizontal component acts in a flowing direction and flows on a parabola. Therefore, since the shape changes greatly depending on the outflow speed, the change in the drop position and the amount of change in the flow rate are large,
This has led to large variations in the quality of slag products and reduced yield.

When a nozzle is provided, as shown in Japanese Patent Application Laid-Open No. 5-9513, it is common to arrange the nozzle at the bottom of the gutter at the same height as the bottom.
In the case of such a nozzle arrangement, the nozzle body and the metal around the nozzle are easily cooled similarly to other parts, so that a solidified material is easily formed. For this reason, the coagulated matter also adheres to the inner surface of the discharge hole of the nozzle, and a phenomenon that the hole diameter becomes small occurs. If the solidified matter adheres to the discharge hole of the nozzle, the streamline is pulled by the solidified matter due to the viscosity of the molten slag flowing out from the discharge hole, and the stream becomes a turbulent flow or causes nozzle clogging.

As a countermeasure, there is a method of heating by applying external energy to the nozzle portion such as induction heating around the nozzle as disclosed in Japanese Patent Application Laid-Open No. 5-43920. There was a problem that it was weak to impact force such as tilting and hitting.

Further, when a discharge nozzle is arranged at the same height or lower than the bottom surface as in the gutter disclosed in Japanese Patent Application Laid-Open No. H11-333549, the temperature of the gutter apparatus is changed when the molten slag is supplied to the gutter. Because the temperature is lower than the temperature, the part where the molten slag solidifies partially floats and flows to the vicinity of the nozzle, and the slag solidified substance attached to the supply port to the gutter in the melting device peels off, Since the molten slag flows into the gutter together with the molten slag, during the discharge of the molten slag from the gutter, the slag solidified in the supply slag to the gutter, or the slag solidified in the gutter or its fragments, or semi-solidified There is a problem that the slag in the state is drawn by the slag in the flowing state and flows into the discharge hole of the nozzle, so that the nozzle is easily clogged.

Therefore, when the nozzle is disposed at the bottom of the gutter, the viscosity of the molten slag is reduced by maintaining the slag at a temperature sufficiently higher than the melting point, and the solidified or semi-solidified matter is easily formed on the liquid level of the slag. It had to be supplied to the gutter so that it could float on the surface. If this is not possible, it is necessary to provide a weir-shaped outlet without providing a hole-shaped outlet.

The molten slag supplied to the gutter is cooled and solidified on the surface in contact with the gutter and on the liquid surface in contact with the atmosphere, and has a thickness of about 100 to 160 mm when the gutter is an iron shell. Reach Therefore, it is necessary to remove this coagulated product.
Conventionally, even if a gutter has a cross-sectional shape that has a gradient such that the solidified material can escape above the gutter, the solidified material adheres to the corner due to the formation of a corner at the line where the surfaces intersect. Since the kimono gradually grew, it had to be removed by a hanging operation.

Further, when the molten slag supplied into the gutter is discharged from the discharge port, when the liquid level rises, the opening cross-sectional area of the discharge weir through which the molten slag passes increases, and a large amount of flow occurs. Can also be handled, so that it does not spill to other places. To control the flow rate, it is common to adjust the height of the weir by changing the height of the weir. At that time, the position of collision or contact with other fluids or equipment changes, and the processing conditions fluctuate, and the quality of the slag product fluctuates.

[0011]

That is, in the structure of the discharge part of the conventional gutter, since the discharge port is open or constituted by a V-shaped or similar weir, the streamline flowing down with respect to the discharge flow rate is reduced. However, there is a problem that the position and shape change.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and is intended for a molten slag for which the falling position of the molten slag is constant irrespective of the discharge speed from the gutter and the nozzle is hardly clogged. It is intended to provide gutters.

[0013]

SUMMARY OF THE INVENTION In order to achieve the above object, a gutter for molten slag according to the present invention has a gutter having an outer surface recessed on an inner surface side at a bottom portion upstream of a discharge-side end surface of the gutter. Forming a nozzle storage portion with the bottom surface on the inner surface side of the gutter protruding into the gutter, and in this nozzle storage portion, one nozzle provided with a discharge hole or a line perpendicular to the flow direction of the molten slag in the gutter is provided. It is said that multiple arrangements were made. By doing so, the flow-down position of the molten slag becomes constant regardless of the discharge speed from the gutter, and nozzle clogging hardly occurs.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION The gutter for molten slag according to the present invention
In a gutter that once receives molten slag and discharges it from the nozzle, a nozzle housing in which the outer surface of the gutter is recessed into the inner surface and the bottom surface on the inner surface of the gutter protrudes into the gutter at the bottom upstream of the discharge-side end surface of the gutter. A plurality of nozzles provided with discharge holes are arranged in this nozzle storage portion on a line orthogonal to the flow direction of the molten slag in the gutter or on a line orthogonal to the flow direction.

In the gutter for molten slag according to the present invention, since the nozzle is disposed at the above-described position, the slag flow discharged from the nozzle flows vertically downward, thereby preventing the flow line from being changed by the discharge flow rate. At the same time, even if the molten slag mixed with the solidified slag and its fragments suspended in the molten slag and the lump of semi-solid slag is received, these solidified lump, its fragments and the lump of semi-solid slag flow. The molten slag in the state is not easily sucked into the discharge hole of the nozzle, so that the nozzle is hardly clogged.

In the gutter for molten slag according to the present invention, a fulcrum capable of tilting to the outer wall surface of the gutter while forming a surface of the inner surface of the gutter which comes into contact with the molten slag upward with a draft of solidified material. Is provided, the gutter can be easily tilted, and the solidified slag attached to the inner surface of the gutter can be easily separated by gravity or impact.

In the gutter for molten slag according to the present invention, if the gutter is provided with a discharge port for overflowing the molten slag, even if the amount of supply to the gutter is larger than the amount of discharge from the nozzle. The level of the slag liquid does not become excessive,
In addition, it can be confirmed visually.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a gutter for molten slag according to the present invention is shown in FIGS.
A description will be given based on one embodiment shown in FIG. FIG. 1 is a schematic explanatory view of an upstream portion of a molten slag processing apparatus provided with a molten slag gutter according to the present invention, wherein FIG.
(B) is a view of the molten slag gutter viewed from a plane, FIG. 2 is an enlarged view of a molten slag gutter nozzle portion according to the present invention, (a) is a cross-sectional side view, (b) ) Is a sectional view taken in the direction of arrow A in FIG. 3A, FIG. 3 is a diagram for explaining a problem when two nozzle holes are provided in the flow direction of the molten slag in the gutter, and FIG. FIG. 5 is a diagram illustrating a molten slag gutter according to the present invention as viewed from a plane, FIG. 5 is a diagram illustrating a molten slag flowing down from the molten slag gutter according to the present invention, and FIG. FIG. 6B is a cross-sectional view taken along the line BB of FIG.
FIG. 3 is an explanatory view of a fulcrum provided on the outer wall surface of the gutter for molten slag according to the present invention.

1 to 3, reference numeral 1 denotes a molten slag gutter according to the present invention, for example, which receives molten slag (hereinafter, referred to as “molten slag”) 3 in a pot 2 and discharges it from a nozzle 4. The outer surface of the gutter 1 is recessed toward the inner surface at the bottom of the discharge-side end surface on the upstream side of the wall surface 1d, and the inner bottom surface 1a of the gutter 1 is moved to, for example, the overflow height of the molten slag 3 (FIG. 1 (a)). 7)), and
The nozzle housing 1b is formed to protrude to a position 150 mm or more above the bottom surface 1a.

The nozzle housing 1b has a gutter 1
One nozzle 4 provided with a discharge hole 4a in the flow direction of the molten slag 3 in the inside (indicated by an arrow 5 in FIGS. 1A, 2 and 3), or as shown in FIG. A plurality of slags 3 are arranged on a line 6 orthogonal to the flow direction 5 of the molten slag 3 in the gutter 1.

The gutter 1 for molten slag according to the present invention comprises:
As shown by the imaginary line in FIG. 6 around the fulcrum 1f provided on the outer wall surface, when the inner surface of the gutter 1 is tilted by 180 degrees and the opening is directed downward, the slag coagulated material is easily removed downward. The surface of the gutter 1 which is in contact with the molten slag 3 on the inner surface of the gutter 1 is formed in a shape having a draft of solidified material facing upward.

The shape of the solidified product having a draft is as follows:
The supply side, the discharge side, and both the wall surfaces 1c to 1e on both sides are not limited to those provided only with a gradient such that the upper side is wider.
For example, as shown in FIG.
a is an arc shape with the upper part being wider, and the supply and discharge sides and both side walls 1c to 1e are provided with a gradient so that the upper part is wider, and the intersection of these wall surfaces 1c to 1e is provided. Is formed in a curved surface, and the nozzle housing portion 1b is also formed in a pyramid shape as shown in, for example, FIG. 1 or FIG. 2B, or the supply side and the discharge portion in the shape shown in FIG. The wall surfaces 1c to 1e on the side and both sides may also be formed in an arc shape in which the upper part is wider. With such a shape, the slag solidified material is more easily removed. In addition, the gutter 1 for molten slag according to the present invention has a gutter 1 provided with a discharge port 1g for overflow of the molten slag 3 on, for example, one wall surface 1c on the supply side.

In the gutter 1 for molten slag according to the present invention, since the nozzle 3 is disposed at the position as described above, the outflow shape of the slag flow discharged from the discharge hole 3a of the nozzle 3 is as shown in FIG. Furthermore, the slag flows down vertically in a cylindrical shape due to the surface tension due to the viscosity of the slag, and even if the discharge flow rate changes, the falling cross-sectional area of the cylindrical shape increases, but the drop position and the position of the streamline do not change.

Therefore, the installation position of the nozzle 9 on the refrigerant side during processing such as water granulation or air blasting can be made as close as possible to the flow of molten slag, or the falling position can be controlled by slag such as collision dispersion operation by utilizing a constant property. , The processing operation becomes easy. Even when a plurality of nozzles 4 are arranged, if the discharge holes 4a are arranged on the line 6 orthogonal to the flow direction 5 of the molten slag 3 in the gutter 1 as described above, the vertically downward position of the discharge hole 4a is the downward position of the molten slag 3. Therefore, the position can be determined.

The slag solidified lumps 3a and their fragments floating in the molten slag 3 have a specific gravity of the molten slag 3a.
It is slightly lighter and floats on the liquid surface of the molten slag 3 or flows while trying to float, and since the specific gravity of the semi-solidified slag 3b is almost the same as that of the slag in the flowing state, the molten slag flowing It is flowing while floating in 3. Further, when the temperature of the molten slag 3 is low, the viscosity is high, and a solidified substance having a low specific gravity cannot easily float.

Therefore, in the gutter 1 for molten slag according to the present invention, the molten slag 3 mixed with the solidified lump 3a of the slag floating in the molten slag 3 from the pan 2 and its fragments, the lump 3b of semi-solidified slag, etc. , The molten slag 3 in the flowing state is discharged from the discharge hole 4a of the nozzle 4 installed at a position higher than the bottom surface 1a on the inner surface side of the gutter 1 as described above, while the solidified mass 3a and its fragments are discharged. The lump 3b of semi-solidified slag passes through the position of the nozzle 4 disposed at the above-described position, and as shown in FIG. 2A, the nozzle storage portion 1b and the wall surface 1d of the discharge side end face are separated from each other. Since it will be deposited in between or will be deposited at a position lower than the nozzle 4,
It becomes difficult to be sucked into the discharge hole 4a of the nozzle 4, and it becomes difficult to close the nozzle.

When two discharge holes 4a are provided in the flow direction 5 of the molten slag 3 in the gutter 1 as shown in FIG. Since the molten slag 3 is discharged first from the discharge hole 4aa on the side, the discharge hole 4aa on the upstream side is not closed, but the solidified lumps 3a, its fragments, and semi-solid slag are collected on the discharge hole 4ab on the downstream side. Since 3b and the like flow in intensively, it was confirmed that the downstream discharge hole 4ab gradually closed and stopped flowing. Therefore, in the gutter 1 according to the present invention, it is better to avoid arranging two or more discharge holes 4a in the flow direction of the molten slag 3 in the gutter 1.

Further, in the gutter 1 for molten slag according to the present invention having the above-described structure, by setting the installation position of the nozzle 4 higher than the bottom surface 1a of the gutter 1, the outer shape of the gutter in the nozzle accommodating portion 1b has a concave shape. Nozzle 4
The portion of the nozzle housing 1b protruding toward the inner surface of the gutter 1 is heated by the molten slag 3 itself, and the outside air 8 located in the recessed portion stays therein, so that heat radiation due to convection heat transfer of the outside air is small. Therefore, the initial solidification amount of the molten slag 3 supplied to the gutter 1, the solidification amount of the nozzle storage portion 1 b on the inner surface side of the gutter 1, and the adhesion amount in the discharge hole 4 a of the nozzle 4 can be reduced. The device can be omitted.

In the molten slag gutter 1 according to the present invention, the gutter 1
Even if the amount of solidification of the molten slag 3 in the inside can be reduced, it does not mean that it is completely eliminated. The solidification range of the molten slag 3 in the gutter 1 is the surface in contact with the gutter 1 and the liquid level 3c of the molten slag 3 in contact with the atmosphere. Except for the supply position 10 and the outflow position of the nozzle 4 from the discharge hole 4a, since the heat supply from the slag itself is small, the slag is solidified to form a film.

Therefore, when the molten slag 3 is supplied to a certain level in the gutter 1 at the initial stage of the supply of the molten slag 3, a film is formed on the surface and the liquid level which affects the outflow from the discharge hole 4a of the nozzle 4 becomes It will be constant.

However, when the supply amount to the gutter 1 is larger than the discharge amount from the discharge hole 4a of the nozzle 4, the hole 3da of the slag solidified film 3d formed at the supply position 10 of the molten slag 3 (see FIG. 3). Since it overflows from the part of ()), it can be easily confirmed visually. This overflow is
Hole 3 of slag solidified film 3d at supply position 10 of molten slag 3
1 g of overflow discharge port provided in the vicinity via da
Therefore, a substantially constant discharge amount can be obtained without applying excessive liquid level pressure to the discharge hole 4a of the nozzle 4.

Further, in the present embodiment, the slag adhered to the inner surface of the gutter 1 is separated from the inner surface of the gutter 1 by its own weight by tilting as shown by the imaginary line in FIG. I do. In order to more effectively remove the adhered slag, the main body of the gutter 1 can be made of a casting or an iron plate, so that it can be easily separated from the slag.

Incidentally, from the blast furnace slag pan having a capacity of 50 ton, a gutter for molten slag according to the present invention having the above-mentioned configuration (width: 1.5 m, length: 4 m, capacity: 4 ton, inclination:
2 degrees with respect to the horizontal), the molten slag having a temperature of 1350 to 1400 ° C. is received at a liquid level of about 200 mm and 15 to 30 tons per hour, and is made of stainless cast steel having a discharge hole having a diameter of 20 mm or As a result of flowing down from the brick nozzle, the nozzle of any material stably flowed out without causing nozzle clogging, and its streamline hardly fluctuated significantly.

[0034]

As described above, according to the gutter for molten slag according to the present invention, granulated water is used for cooling and crushing molten slag in a blast furnace or steelmaking furnace with a large amount of water, or dispersed and solidified with a large amount of gas. When performing processing such as wind crushing to make sand, the outflow position and speed of the outflow of molten slag are stable, so that the nozzle of water or compressed gas can be as close as possible to the molten slag fluid, and granulated slag, Fluctuations in the processing conditions of the crushed slag can be reduced, which can greatly contribute to improving the quality and yield of the slag product.

Further, when the inner surface of the gutter is formed so that the surface of the inner surface of the gutter which comes into contact with the molten slag is directed upward so that the solidified material can easily escape, and if a tiltable fulcrum is provided on the outer wall surface of the gutter, the adherence of the adhered material is reduced. In the waste removal operation, the slag solidified only by tilting with a winch or the like is peeled off and dropped off only by its own weight, so that a hanging operation by a human is unnecessary.

When the gutter is provided with a discharge port for overflowing the molten slag, the level of the molten slag liquid level does not become excessive even when the supply amount to the gutter is larger than the discharge amount from the nozzle. In addition, it can be confirmed visually.

Also, in powder metallurgy, as a method of dispersing and solidifying a molten metal in a fine spherical shape, a compressed gas is sprayed on a liquid metal at a high speed to disperse the liquid metal. Since it is desired that the amount is as small as possible, the molten slag gutter according to the present invention can be effectively used.

[Brief description of the drawings]

FIG. 1 is a schematic explanatory view of an upstream portion of a molten slag processing apparatus provided with a molten slag gutter according to the present invention, wherein (a) is a side view, and (b) is a molten slag gutter viewed from a plane. FIG.

FIG. 2 is an enlarged view showing a gutter nozzle portion for molten slag according to the present invention, wherein (a) is a side view showing a cross section, and (b).
2 is a sectional view taken along the arrow A in FIG.

FIG. 3 is a view for explaining a problem when two nozzle holes are provided in a flow direction of a molten slag in a gutter.

FIG. 4 is a plan view of a molten slag gutter according to the present invention when there are a plurality of nozzle holes.

FIGS. 5A and 5B are diagrams illustrating a state of molten slag flowing down from a molten slag gutter according to the present invention, wherein FIG. 5A is a side view, and FIG. 5B is a BB cross-sectional view of FIG. is there.

FIG. 6 is an explanatory view of a fulcrum provided on an outer wall surface of the molten slag gutter according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Gutter 1a Bottom surface 1b Nozzle accommodating part 1c Supply-side wall surface 1d Discharge-side wall surface 1e Both-side wall surface 1f Support point 1g Discharge port 3 Melt slag 4 Nozzle 4a Discharge hole 5 Flow direction of molten slag in gutter 6 line 9 nozzle

Claims (3)

[Claims] In a gutter for receiving molten slag once and discharging it from a nozzle, an outer surface of the gutter is recessed into an inner surface at a bottom portion upstream of a discharge-side end surface of the gutter, and a bottom surface of the inner surface of the gutter is inserted into the gutter. A protruding nozzle accommodating portion is formed, and a plurality of nozzles provided with discharge holes are arranged in this nozzle accommodating portion on one or a line orthogonal to the flow direction of the molten slag in the gutter. Slag gutter. 2. The method according to claim 1, wherein a surface of the gutter contacting the molten slag on the inner surface of the gutter is formed upward in a shape having a draft of the solidified material, and a tiltable fulcrum is provided on an outer wall surface of the gutter. The molten slag gutter according to claim 1. 3. The molten slag gutter according to claim 1, wherein a drain port for overflowing the molten slag is provided in the gutter.