JPH0448026A - Vacuum suction type continuous degassing device - Google Patents

Abstract

PURPOSE:To easily remove the gaseous components in a melt with a small amt. of gaseous argon by bringing one surface of a porous member which allows the diffusion of gases but does not allow the infiltration of the melt into contact with the melt, placing the other surface under a vacuum, and passing a cooling medium into the core material in the porous member. CONSTITUTION:A melt flow pipe 15 is formed of the porous material and has the pores which allow the diffusion of the gases but prohibits the infiltration of the melts 2, such as molten metal and molten slag. A pipe-shaped core material 16 is embedded like a coil into the wall of the melt flow pipe 15. The cooling medium, such as gas or liquid, flows in this material. The part in contact with the flow pipe 15 is exposed to the vacuum state through the flow pipe 15 when the melt 2 flows in the flow pipe 15 and passes in a vacuum vessel 14. The gases in the melt or the gases generated by the reaction of the melt 2 and the porous member are removed in this way. The continuous treatment to remove the gas forming components from the melt 2 is thus executed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention provides a method for removing solute components that generate a gas phase from a melt such as a molten metal, a molten matte, and a molten slag through a porous member. Or, it relates to a vacuum suction type continuous degassing device for recovery.

[Prior Art] Conventionally, there are degassing methods such as the RH method and the DH method as technologies for removing or recovering solute components that generate a gas phase from melts such as molten metal, molten matte, and molten slag. . In the RH method and the DH method, a large amount of argon gas is blown into the molten metal under vacuum or reduced pressure to reduce the partial pressure of the gas component in the molten metal and remove this gas component.

[Problems to be Solved by the Invention] However, the conventional degassing methods using the RH method and the DH method use a large amount of argon gas, and therefore have a drawback of high running costs.

In addition, since a large amount of argon gas is blown into the molten metal, splashes are generated from the molten metal, and base metal adheres to the walls of the apparatus, making the removal work complicated. Furthermore, because this splash occurs, the equipment has to be made larger.
Equipment costs are also high.

The present invention has been made in view of such problems, and includes:
Vacuum suction continuous degassing allows gas components in the melt to be removed into the container without using large amounts of argon gas, and degassing of the melt can be carried out with simple equipment at low cost. The purpose is to provide equipment.

[Means for Solving the Problems] The vacuum suction type continuous degassing device according to the present invention has one surface of a porous member formed of a porous material that allows gas to pass through but not the melt to pass through the melt. vacuum suction type continuous desorption for separating the gas in the melt or the gas generated by the reaction between the melt and the components of the porous member from the melt with the other side under vacuum or reduced pressure. In gas equipment,
a pipe-shaped core material disposed inside the porous member;
It is characterized by having a cooling means for causing a cooling medium to flow through the core material. Note that, in order to prevent the temperature of the melt from decreasing, it is preferable to have a heating means (for example, plasma heating) that performs external heating.

[Function] FIG. 4 is a schematic diagram showing the principle of the present invention. The porous member 1 is a member made of a porous material that allows only gas to pass therethrough and does not allow melts such as molten metal, molten matte, and molten slag to pass therethrough. When the molten material 2 is brought into contact with one surface of this porous member 1 and the other surface is placed in a vacuum or reduced pressure atmosphere 3, the static pressure of the molten material 2 is irrelevant to the wall surface in contact with the molten material 2. pressure decreases.

Therefore, impurity components in the melt 2 or valuable components that have a value to be recovered, which generate a gas phase, easily nucleate on the wall surface of the porous member 1, and the generated gas 4 It passes through the mass member 1 and is separated from the melt 2.

The inventors of the present application have come up with the idea that gas-generating components can be removed from a molten material based on such a principle, and have completed the present invention.

Thus, the gas-generating components dissolved in the melt are removed in the form of gas according to the reaction formula below.

Roof tiles +, N-→N2...(1) Upper L+upper L=82 ・
... (2) U + bypass → CO ... (3) i + 2Ω- → SO2 ... (4) Also, after the impurities in the melt react with the components of the porous member and become gas, It may also be removed by passing through the material.

When the porous member is an oxide (M, OY), carbon in the melt is converted into gas and removed according to the following reaction formula.

Y f, + M x Oy (solid) → Xl1iL+
YCO (5) Furthermore, when the porous member is made of carbon or contains carbon as one component, oxygen in the melt is removed according to the following reaction formula.

Ω-+C (solid)→CO (6) Furthermore, the valuable component (M) having a high vapor pressure in the melt is separated and recovered by gasifying the valuable component according to the following reaction formula.

xM=Mx (gas)...(7)
MOY-MO, (gas) river (8) MS, →M
SY (gas) (9) In this way, impurity components and valuable components such as N, H, C, O, and S in the melt are removed or recovered from the melt.

The material of the porous member is Al2O2, Mg0tC
a0XS i02 , Fe2O3, Fea Oa , C
r20G, BNN S 13N4 and SiC and C
Various metal oxides, metal non-oxides, carbon, and mixtures thereof can be used, but those that do not react with the main components of the melt are preferred. In this manner, by not reacting with the main component, the partition member that comes into contact with the melt is prevented from being melted and damaged.

Furthermore, in order to allow only the gas to pass through and not the molten material, a partition member made of a porous material that is difficult to get wet with the molten material is used. Furthermore, the porosity of the partition member is preferably 40% or less. Furthermore, although it varies depending on the wettability of the partition member to the melt, the pore diameter of the partition member is about 20
It is preferable to set it to 0 micrometer or less.

Accordingly, in the present invention, when forming these materials into a porous member, a core material is placed inside the porous member in order to reinforce the strength of the porous member. However, when the degassing operation is performed continuously, the temperature inside the porous member increases and the core material placed inside the porous member becomes soft.
Otherwise, there is a risk that the porous member will be destroyed by melting. Therefore, in the present invention, the core material is formed of a pipe-shaped material, and a cooling medium such as gas or liquid is caused to flow through the core material by a cooling means. This avoids softening and melting of the core material, prevents destruction of the porous member, and allows continuous degassing of the molten material. Additionally, if molten material enters a pinhole in a porous member, the molten material is cooled and solidified by the core material through which the cooling medium flows, preventing the molten material from penetrating any deeper. .

In order to prevent the melt from entering the vacuum piping system even if the melt enters the vacuum (or reduced pressure) space inside the porous member, a filter with low pressure loss is installed above the porous member to prevent the melt from entering. It is preferable to use this filter to solidify and trap the molten material.

Next, an application example in which the present invention is applied to the removal and recovery of gas generating components from a melt will be described.

(1) First, the present invention can be used in decarbonization, denitrification, and dehydrogenation processes for removing carbon, nitrogen, or hydrogen from molten iron.

When illegally removing carbon from molten iron, the main component of the partition member is AlzOa or MgO, and FeQOa+Fe 3041 is used as the main oxidizing agent for carbon in molten iron.
Blend M n O+ S s 02, etc. By increasing the blending ratio of these main oxidizing agents, the rate of oxygen removal from molten iron can be increased. However, if the blending ratio of the main oxidizing agent is too high, it will lower the melting point or mechanical strength of the partition member, and especially if the carbon concentration in the molten iron is low, the oxygen concentration in the molten iron will increase. Depending on the purpose, the blending ratio of the main oxidizing agent is determined with reference to the already established rod diagram.

On the other hand, if illegal methods are used to remove nitrogen from molten iron, the partition member may contain stable oxides such as CaCLAr
103, MgO, etc. are used.

Furthermore, when using an illegal method to simultaneously remove carbon and nitrogen from molten iron, the blending ratio of the main oxidizer is changed depending on the target concentration of carbon and nitrogen in molten iron.

(2) The present invention can also be applied to a deoxidation process for removing oxygen from molten steel.

(2) Furthermore, the present invention can also be applied to a dehydrogenation process for removing hydrogen from molten aluminum.

(2) Furthermore, the present invention can be applied to decarbonization, denitrification, and dehydrogenation of molten silicon.

(2) On the other hand, according to the present invention, zinc in the melting vessel can be recovered.

■ Desulfurization O to remove sulfur and oxygen from molten steel matte
The present invention can also be applied to the process of deoxidizing.

(2) Valuable metals (As, sb, Bi, Se, Te) in the molten steel matte or nickel matte.

The present invention can also be applied to the recovery of Pb, Cd, etc.).

■ Furthermore, valuable metals (A s + Sb
The present invention can also be applied to the case of recovering (Bit Se+ Te+ pb, ca, Zn, etc.).

[Embodiments] Next, embodiments of the present invention will be described with reference to the accompanying drawings.

FIG. 1 is a schematic sectional view showing a vacuum suction type continuous degassing apparatus according to a first embodiment of the present invention.

A cylindrical melt flow pipe 15 made of a porous material is disposed to penetrate inside the vacuum container 14 . A melt flow pipe 15a is connected to both ends of the melt flow pipe 15.

The vacuum container 14 is connected to a suitable vacuum pump, and the inside of the vacuum container 14 is maintained in a vacuum state.

The melt flow pipe 15 is formed of a porous material, and the melt flow pipe 15 is made of a fine material that allows gas to pass therethrough but prevents the melt 2 such as molten metal, molten slag, and molten mat from penetrating. It has a hole. Further, a pipe-shaped core material 16 is embedded in the pipe wall of the melt flow pipe 15 in the form of a coil. A cooling medium such as gas or liquid is allowed to flow inside the core material 16 .

In the vacuum suction type continuous degassing apparatus configured in this way, the melt 2 flows through the flow pipe 15 and when passing through the vacuum container 14, the melt 2 comes into contact with the flow pipe 15. The section is exposed to a vacuum via the flow tube 15 made of this porous material. As a result, the gas in the melt 2 or the gas generated by the reaction between the melt 2 and the porous member is removed while flowing through the vacuum vessel 14, and the gas generating components are removed from the melt 2. continuous processing is possible.

In this case, in this embodiment, since the cooling medium is flowing through the core material 16 buried in the flow pipe 15, the molten material 2
This prevents the core material 16 from softening and melting due to heat from the inside.

Therefore, - long-term degassing treatment is possible. Further, for example, if there is a pinhole in the melt flow pipe 15 and the melt 2 enters the vicinity of the core material 16 through this pinhole, the temperature of the melt 2 is lowered and solidified. It also has the effect of preventing intrusion into the vacuum atmosphere side.

FIG. 2 is a cross-sectional view showing a vacuum suction type continuous degassing apparatus according to a second embodiment of the present invention.

Inside the box-shaped container 20, a plurality of plate-shaped weirs 21 (three in the illustrated example) are arranged parallel to each other at appropriate length intervals. Each layer 21 has a plurality of molten material passage holes 22 arranged in the height direction of the weir 21 and bored through one end in the width direction thereof in the thickness direction. Further, each layer 21 is formed with a plurality of gas suction holes 23 (five in the illustrated example) arranged in the width direction of the weir 21 and passing through the layer 21 in the height direction. Furthermore, a vibrator-shaped core material 24 is embedded in the weir 21. This weir 21 allows gas to pass through, but molten metal,
The molten material, such as molten slag and molten matte, has pores that cannot be penetrated, and the molten material is formed of a porous material that is impermeable. Further, the container 20 is provided with an inlet 20a and an outlet 20b for the melt 2.

In the vacuum suction type continuous degassing apparatus configured in this way, the melt 2 enters the container 20 from the inlet 20a and passes through the weir 2.
1, the flow trajectory is regulated. This molten body 2 is a weir 2
The molten material passes through the melt passage hole 22 of No. 1 and flows in a zigzag shape in the container 20 as shown by the arrow in the figure in a plan view. On the other hand, the gas suction hole 23 provided in the weir 21 is maintained in a vacuum state through a pipe (not shown), and the molten material 2 is regulated in its flow path by the weir 21 while flowing through it. , are exposed to a vacuum condition via the weir 21. As a result, gas generating components in the melt 2 are removed. In this case, since the core material 24 through which the cooling liquid or cooling gas flows is embedded in the weir 21, the core material 24 is prevented from softening or melting. Therefore, continuous operation of the device is possible. Furthermore, if there is a pinhole in the porous material constituting the weir 21 and the molten material 2 enters the weir 21 through this pinhole, the molten material 2 is cooled and solidified near the core material 24. Therefore, melt 2
can be prevented from entering into the gas suction hole 23.

In this embodiment, the molten material can be continuously degassed, and the area in which the molten material contacts the porous member is larger than in the embodiment shown in FIG. Gas generating components can be removed with high removal efficiency.

FIG. 3 is a sectional view showing a vacuum suction type continuous degassing apparatus according to a third embodiment of the present invention.

The melt 2 flows into the container 31 from near one wall surface of the box-shaped container 31 via the melt inlet 33, flows laterally within the container 31, and then flows through the one wall surface of the container 31. The molten material flows out from the vicinity of the other wall surface facing the molten material through an outlet 34.

The degassing member 32 includes a plurality of partition members 32b each having a cylindrical shape with a closed lower end, and these partition members 32.
b and a dense member 32a connected to the upper end portion of the member b. This degassing member 32 has a pipe-shaped core material (
(not shown) is embedded, and the end of the core material is led out to the outside and connected to a cooling device that allows cooling gas or liquid to flow through the core material. The degassing member 32 is placed on the container 31 with the partition member 32b immersed in the melt 2. Further, the degassing member 32 is connected to a suitable vacuum device, and the inside of the degassing member 32 is sucked by this vacuum device to be in a vacuum state.

The partition member 32b has pores that allow gas to pass therethrough but prevent molten substances such as molten metal, molten slag, and molten mat from penetrating, and the partition member 32b is made of a porous material that does not allow this molten substance to pass through. There is. On the other hand, the dense member 32a is made of a material that does not allow gas to pass through, or has been treated to prevent gas from passing through.

This degassing member 32 is made of, for example, a core material which is a pipe assembled in a predetermined shape, a porous material is placed around this core material, and is formed into the shape of the degassing member 32, and is made of a dense material 32(). It can be created by coating the portion with a dense material that does not allow gas to pass through.

In the vacuum suction type continuous degassing apparatus configured in this way, the melt 2 enters the container 31 from the inlet 33, and the melt 2 enters the container 31 through the inlet 33.
1 flows laterally and exits from the outlet 34. On the other hand, the inside of the degassing member 32 is maintained in a vacuum, and while the melt 2 flows through the container 31, it is exposed to the vacuum state via the partition member 32b.

Then, the gas generating components in the melt 2 pass through the partition member 32b and move into the degassing member 32.

As a result, gas generating components are removed from the melt 2.

In this case, since cooling gas or cooling liquid is flowing through the core material embedded in the degassing member 32, the melt 2
The core material can be prevented from softening or melting due to the heat, and the molten material 2 can be continuously degassed. Furthermore, the molten material 2 that attempts to enter the degassing member 32 through, for example, a pinhole in the partition member 32b is cooled and solidified by the gas or liquid flowing through the core material, so that the molten material 2 inside the degassing member 32 is It is possible to prevent the molten material 2 from entering the molten material.

In each of the above embodiments, the relationship between the melt and the porous material component of the melt flow pipe (first embodiment), weir (second embodiment), or partition member (third embodiment) If the endothermic reaction lowers the temperature of the melt and interferes with the degassing process, an external heating device may be installed to raise the temperature of the melt.

In addition, in order to prevent the melt from entering the vacuum equipment due to damage to the melt flow pipe, weir, or partition member, a filter with low pressure loss is installed between the degassing equipment and the vacuum equipment. , the molten material may be solidified and trapped in this filter.

[Effects of the Invention] As explained above, according to the present invention, one surface of a porous member formed of a porous material that is permeable to gas but not permeable to the melt is in contact with the melt, and the other surface is in contact with the melt. Since it is placed under vacuum or reduced pressure, the solute component in the melt can be easily separated from the melt via the porous member. Also,
A pipe-shaped core material is embedded inside the porous member, and a cooling medium is allowed to flow through the core material, so that softening and melting of the core material can be avoided.
Degassing of the melt can be carried out continuously. Note that if the partition member is worn out during the degassing treatment of the molten material, it is preferable to repair it as appropriate.

Unlike the conventional degassing method, which blows in highly poisonous argon gas, the present invention does not blow in argon gas, or only needs to blow in a small amount of argon gas to stir the molten metal.
The unit consumption of argon gas can be significantly reduced. Furthermore, since the amount of argon gas used is extremely small, the occurrence of splash is suppressed, and it is possible to reduce the appearance of metal on the wall of the apparatus. Therefore, according to the present invention, it is possible to reduce the cost of the device by downsizing the device, and also to significantly reduce the running cost of the device.

[Brief explanation of the drawing]

FIG. 1 is a schematic sectional view showing a vacuum suction type continuous degassing device according to the first embodiment of the present invention, and FIG. 2 is a schematic sectional view showing a vacuum suction type continuous degassing device according to the second embodiment of the present invention. FIG. 3 is a cross-sectional view showing a vacuum suction type continuous degassing apparatus according to a third embodiment of the present invention, and FIG. 4 is a schematic diagram showing the principle of the present invention. 1; Porous member, 2; Melt, 3; Vacuum or reduced pressure atmosphere,
4: Gas, 14; Vacuum container, ■-5: Melt flow pipe, 15
a; Melt flow piping, 16; Core material, 20: Container, 20a;
Inlet, 20b: Outlet, 21; Weir, 22; Melt passage hole, 2
3; Gas suction hole, 24; Heart material, 31: Container, 32: Degassing member, 32a; Dense member, 32b; Partition member, 3
3: Entrance, 34; Exit

Claims (1)

[Claims] (1) One side of a porous member molded from a porous material that permeates gas but not the molten material is brought into contact with the molten material, and the other surface is placed under vacuum or reduced pressure to remove the gas in the molten material or A vacuum suction type continuous degassing device that separates a gas generated by a reaction between the melt and a component of the porous member from the melt, a pipe-shaped core disposed inside the porous member; A vacuum suction type continuous degassing device characterized by having a cooling means for causing a cooling medium to flow through the core material.