JPS63162822A - Revolving cooling body for purifying device of metal - Google Patents

Abstract

PURPOSE:To prevent the furious rippling on a molten metal surface and to reduce the amount of the sludge coming out, by making the submerged part of a revolving cooling body under the surface of a molten metal in such a way that the upper part of the submerged part is expanded downwards so as to be a downward guiding part for molten metal. CONSTITUTION:A specified amount of melted Al 4 is put in a crucible 1, and the revolving cooling body 2 is submerged so as to position the molten metal surface at the place between the upper end and the max. diameter part 2a of the revolving body 2 so that the part between the upper end and the max. diameter part 2a works as the downward guiding part 6 for the molten Al. And the inner peripheral part of the part between the upper end and the max. diameter part 2a is covered with an insulating material 7. Then, the revolving cooling body 2 is revolved while a cooling liquid is supplied to the inner part of the revolving cooling body 2 with the result that an Al nodule I of high purity is formed on the outer peripheral part lower than the max. diameter part 2a. At this time, downward streams are generated along the direction as shown by arrow A to prevent the furious rippling on the molten metal surface and the sludge consisting of Al2O3 produced by the reaction between Al and O2 in the air is reduced.

Description

[Detailed Description of the Invention] Industrial Application Field The present invention is used in an apparatus for producing metals of higher purity by refining various metals containing eutectic impurities such as aluminum, silicon, magnesium, lead, and zinc. The present invention relates to a rotary cooling body.

Prior Art and its Problems For example, a method is known in which aluminum to be purified, which contains impurities that form eutectic with aluminum, is purified to a higher purity by utilizing the principle of segregation solidification. and,
As shown in FIG. 7, the apparatus used to carry out such a method includes a crucible (1) for holding molten aluminum (4), and a crucible (1) for holding molten aluminum (4). ), and the rotary cooling body (30) has a tapered shape that gradually becomes thinner downward from the upper end. After melting the aluminum, the molten aluminum (4) is placed in the crucible (1) and kept heated to a temperature that exceeds its solidification temperature, and then cooled into the heated molten aluminum (4). By immersing the cooling body (30), maintaining the surface temperature of the cooling body (30) below the solidification temperature, and rotating the cooling body (30) to disperse and mix the impurities discharged near the solidification interface. , the thickness of the impurity-concentrated layer near the solidification interface in the liquid phase is reduced, and as a result, while increasing the temperature gradient in the liquid phase at the impurity-concentrated layer, purity is increased by the circumferential surface of the cooling body (30). Aluminum is refined by crystallizing aluminum with high aluminum content. In the above, in order to reduce the thickness of the impurity concentrated layer near the solidification interface in the liquid phase and thereby increase the temperature gradient to improve purification efficiency, the cooling body (30) and the molten aluminum (4 ) The condition is that the relative speed with respect to
It is one. However, as the cooling body (30) rotates, the molten aluminum (4) also flows in the same direction as the rotational direction of the cooling body, creating a vortex, so there is a limit to the increase in the relative speed, and the improvement in refining efficiency is limited. There are also limits. Moreover, if the rotational speed of the cooling body (30) is increased, centrifugal force increases, making it difficult for crystallized high-purity aluminum to adhere to the circumferential surface of the cooling body (30), resulting in a decrease in productivity.

Therefore, in order to solve this problem, a device was devised in which a plurality of baffles (3) for reducing the flow rate of molten aluminum are provided on the inner peripheral surface of the crucible (1) at predetermined intervals in the circumferential direction. (Refer to Utility Model Publication No. 61-38912). Although this apparatus can further improve purification efficiency, the following problems arise. That is, when the baffle plate (3) is present, the flow velocity is partially different, and as a result, the flow rate of the molten aluminum (4) along the circumferential surface of the cooling body (30) as shown by the arrow (E) in FIG. An upward flow is generated, the liquid surface is violently rippled, air is drawn into the molten aluminum (4), and this air and aluminum react to generate a large amount of slag made of A/203. Therefore, sludge removal work is required, and the sludge scatters and adheres to the inner surface of the crucible (1), causing trouble in the work. Furthermore, a large amount of slag is generated, which may reduce purification efficiency.

An object of the present invention is to provide a rotary cooling body for a metal refining apparatus that solves the above problems.

Means for Solving the Problems A rotary cooling body for a metal refining device according to the present invention comprises a crucible and a rotary cooling body that is movable up and down, and the rotary cooling body is immersed in molten metal placed in the crucible. A rotary cooling body used in a metal refining device that crystallizes highly pure metal from its circumferential surface while rotating the rotating cooling body, and the upper part of the part located below the molten metal surface crystallizes the molten metal. The molten metal flow downward guide section has a lower floor shape.

Embodiments Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, the rotary cooling body of the present invention is applied to an apparatus for producing high-purity aluminum. Note that the same parts and parts are denoted by the same reference numerals throughout the drawings.

Example 1 This embodiment is shown in FIG.

In Fig. 1, the high-purity aluminum production equipment consists of a graphite melt holding crucible (1), a rotary cooling body (2) that can move up and down, and an inner wall of the crucible (1) spaced at a predetermined interval in the circumferential direction. It consists of a plurality of baffle plates (3) for reducing the flow rate of molten aluminum detachably fixed to the circumferential surface.

The amount of molten aluminum (4) placed in the crucible (1) is determined to be approximately constant. The rotary cooling body (2) is a hollow body made of graphite, ceramics, etc., and gradually becomes thicker from the upper end toward the bottom and gradually becomes thinner from the middle part of its length toward the lower end. . The rotary cooling body (2) is attached to the lower end of the hollow rotary shaft (5), and cooling fluid is supplied therein from a cooling fluid supply pipe (not shown) disposed within the hollow rotary shaft (5). It is now being supplied. Further, the rotary cooling body (2) is configured such that the liquid level of the molten aluminum (4) is in the cooling body in a predetermined amount of molten aluminum (4) placed in the crucible (2) during the production of high-purity aluminum. The molten aluminum flow downward guide section (6) is immersed between the upper end of (2) and the maximum diameter section (2a) at the middle part of the height, and between the liquid level and the maximum diameter section (2a) is the molten aluminum flow downward guide section (6). It is said that Moreover, the space between the upper end and the maximum diameter portion (2a) on the inner circumferential surface of the rotary cooling body (2) is covered with a heat insulating material (7).

In such a configuration, molten aluminum (4) to be purified containing eutectic impurities such as Fe, S is Cu, Mg, etc., melted in a melting furnace (path shown) is fed into the crucible (1). At this time, the rotary cooling body (2) is in the raised position and outside the crucible (1). After a predetermined amount of molten aluminum (4) is placed in the crucible (1), the rotary cooling body (2) pours the molten aluminum (4) so that the liquid level is between its upper end and the largest diameter portion (2a). ) is immersed in

Then, when the rotary cooling body (2) is rotated while supplying cooling fluid to the inside of the rotary cooling body (2), this rotary cooling body (
In the portion below the maximum diameter portion (2a) on the outer circumferential surface of 2), high-purity primary aluminum having a smooth solidified surface is first crystallized. The eutectic impurities are discharged into the liquid phase, forming an impurity-concentrated layer of eutectic impurities in the liquid phase near the solidification interface. Due to the rotation of the rotary cooling body (2), the molten aluminum (4) also flows in the same direction as the rotating direction of the rotary cooling body (2), but the flow velocity of the molten aluminum (4) is reduced by the baffle plate (3). The difference in the relative velocity between the rotary cooling body (2) and the liquid phase, that is, the circumferential speed of the rotary cooling body (2) and the flow velocity of the molten aluminum (4), becomes considerably large. Therefore, the impurity concentration layer formed near the interface is effectively stirred and mixed with most of the other liquid phase, and the impurities in the impurity concentration layer are dispersed throughout the liquid phase, resulting in impurity concentration. The thickness of the layer becomes thinner and the temperature gradient in this region also becomes larger.

Furthermore, the baffle plate (3) also generates a turbulent flow of the molten aluminum (4), which also causes the impurity concentrated layer to become thinner. If solidification is allowed to proceed in this state, an aluminum lump (1) with much higher purity than the original aluminum is obtained on the circumferential surface of the cooling body (2).

At this time, in the vicinity of the cooling body (2), the molten aluminum (
4), but a downward flow as shown by the arrow (A) in FIG. 1 is generated above the maximum diameter portion (2a), that is, along the molten aluminum flow downward guide portion (6).

Therefore, violent ripples on the liquid surface are prevented, and A resulting from the reaction between oxygen in the air and aluminum
The amount of slag consisting of /203 is reduced.

In this embodiment, the inner peripheral surface of the portion of the rotary cooling body (2) above the maximum diameter portion (2a) is covered with a heat insulating material. The outer peripheral surface of the portion above the maximum diameter portion (2a) may be covered with a heat-resistant heat insulating material, or the entire portion above the maximum diameter portion (2a) may be covered with a heat-resistant heat insulating material. You can also make it with Also, the maximum diameter part (2a)
The thickness of the peripheral wall in the upper part may be increased to provide heat insulation to this part.

Example 2 This embodiment is shown in FIG.

The rotary cooling body (2) of this embodiment has a maximum diameter portion (2a)
The structure is the same as that of the rotary cooling body of Example 1, except that the inner circumferential surface of the upper portion is not covered with a heat insulating material.

In the production of high-purity aluminum, a cooling body (2) is installed along the molten aluminum flow downward guide section (6).
A downward flow as shown by the arrow (B) is generated in the vicinity of , and ripples on the liquid surface are prevented.

Example 3 This embodiment is shown in FIG.

In FIG. 3, the rotary cooling body (11) is hollow and has a cylindrical shape with the same diameter over a predetermined length from the upper end (
This cylindrical portion is indicated by (Lla)).

A curved enlarged portion (llb) is provided at the lower end of the curved enlarged portion (llb) which curves downward and spreads outward.
b) A portion is provided at the lower end that gradually tapers downward. A molten aluminum flow downward guide portion (12) is formed by the portion of the cylindrical portion (lla) below the liquid level and the curved enlarged portion (ttb). Further, the inner peripheral surfaces of the cylindrical portion (lla) and the curved enlarged portion (llb) are covered with a heat insulating material (13). Further, the rotary cooling body (11) is immersed in molten aluminum (4) placed in the crucible (1) during the production of high-purity aluminum so that the liquid level is at the cylindrical part (lla). Ru.

In such a configuration, during the production of high-purity aluminum, a downward flow as shown by the arrow (C) in Fig. 3 occurs along the molten aluminum flow downward guide section (12), resulting in severe ripples on the liquid surface. is prevented from occurring. Therefore, the amount of slag made of Al2O3 produced as a result of the reaction between oxygen in the air and aluminum is reduced.

In this embodiment, the inner peripheral surfaces of the uniform cylindrical part (lla) and the curved enlarged part (llb) of the rotary cooling body (11) are covered with a heat insulating material (13), but instead of this, The outer peripheral surfaces of these parts (lla) (llb) may be covered with a heat-resistant heat insulating material, or these parts may be entirely made of a heat-resistant heat insulating material. Also,
The peripheral walls of the cylindrical portion (11a) and the curved enlarged portion (llb) may be made thicker to provide heat insulation to these portions.

Example 4 This embodiment is shown in FIG.

In FIG. 4, the rotary cooling body (15) is hollow and has a cylindrical shape that gradually becomes thicker downward from the upper end.

The upper part of the part below the liquid level of molten aluminum serves as a molten aluminum flow downward guide part (1B).

In such a configuration, during the production of high-purity aluminum, a downward flow as shown by the arrow (D) in Fig. 4 occurs along the molten aluminum flow downward guide part (1B), resulting in severe ripples on the liquid surface. is prevented from occurring. Therefore, the amount of slag made of A/203 produced as a result of the reaction between oxygen in the air and aluminum is reduced.

In addition, in this embodiment, the upper inner peripheral surface or upper outer peripheral surface of the rotary cooling body (15) may be covered with a heat-resistant insulating material, or the upper part of the rotary cooling body (15) may be made of a heat insulating material. Alternatively, the upper circumferential wall of the rotary cooling body (15) may be made thicker to provide heat insulation to this portion.

Example 5 This embodiment is shown in FIG.

In FIG. 5, the high-purity aluminum manufacturing apparatus has four crucibles (IA) to (ID) arranged next to a melting furnace (17) for melting aluminum to be purified, and four crucibles (LA) to ( 10), a baffle plate (3) is provided in the same manner as in the apparatus of the above embodiment. Further, a rotary cooling body (2) for crystallizing high purity aluminum is provided corresponding to each of the crucibles (IA) to (ID), which is movable up and down. Adjacent crucibles (IA) to (ID) are connected to each other by a connecting gutter (18) at the upper end, and a melting furnace (17) is connected to the leftmost crucible (IA).
) A gutter (19) is attached to the receiver for receiving molten aluminum supplied from the crucible (10) at the right end.
A molten metal discharge gutter (20) is attached to the upper end.

In the apparatus for manufacturing high-purity aluminum having such a configuration, aluminum to be purified is melted in the melting furnace (17) and sent to each of the crucibles (IA) to (ID). When the amount of molten metal in each crucible (IA) to (ID) reaches a predetermined amount, the cooling body (2) is lowered and immersed in the molten metal, and cooling fluid is supplied to the inside from the hollow rotating shaft (5). Rotate this while doing so. Then, due to the principle of segregation solidification, high-purity aluminum is crystallized only on the peripheral surface of the lower portion of the maximum diameter portion (2a) of the rotary cooling body (2).

The eutectic impurities are expelled into the liquid phase and are moved away from the cooling body (2) by the centrifugal force generated by the rotation of the cooling body (2). In this way, aluminum of higher purity and desired purity than the original aluminum supplied from the melting furnace (17) is obtained. The function of the rotary cooling body (2) in each of the crucibles (IA) to (ID) is the same as in the apparatus of Example 1 above.

In this example, if the aluminum to be purified contains impurities that form peritectics with aluminum, a boron oxide film equipped with a stirrer between the melting furnace (17) and the leftmost crucible (LA) is used. It is best to have an addition crucible in place. Then, the molten metal is first fed into this crucible from the melting furnace (17), boron is added to the molten metal in this crucible, and the mixture is stirred by the above-mentioned stirrer. Then, boron reacts with peritectic impurities such as Ti5VsZr contained in the molten metal, and Ti
Insoluble borides such as B2, VB2, and ZrB2 are produced. Excess boron is removed as a eutectic impurity.

The boride is transferred to the cooling body (2) by centrifugal force generated by the rotation of the cooling body (2) in the crucibles (IA) to (ID).
and is no longer included in the aluminum crystallized on the circumferential surface of the cooling body (2).

Example An example of this is shown in FIG.

The apparatus shown in Fig. 6 differs from the aluminum refining apparatus shown in Fig. 1 in that a baffle plate (3) is not provided on the inner peripheral surface of the crucible (1), and rotary cooling Body (2) has the same configuration.

Further, in the metal refining apparatus using the rotary cooling body of Examples 2 to 4 and the metal refining apparatus of Example 5, the baffle plate may not be provided on the inner peripheral surface of the crucible (1).

Next, an example of operation performed using the rotary cooling body of this invention is as follows.
This will be explained along with an example of comparison operation.

Operation Example 1 This operation example was performed using the apparatus of Example 1.

Six baffle plates (3) were provided on the inner peripheral surface of the crucible (1). Further, the outer diameter of the maximum diameter portion (2a) of the cooling body (2) was set to 150 cm. And in the crucible (1),
Molten aluminum (4) containing 0.07 vt% of Fe and 04 wt% of SiO was introduced and kept heated at 670°C. Next, the rotary cooling body (2) was immersed in the molten aluminum (4), and was rotated at a rotational speed of 400 rpa+ while supplying cooling fluid to the inside thereof. Repeat this operation for 30
After the cooling was carried out for a minute, the rotation of the cooling body (2) was stopped and the cooling body (2) was raised. 10 kg on the circumference of the cooling body (2)
Aluminum lumps were crystallizing. After that, the cooling body (2
) was removed, and the average impurity concentration of Fe and Si in the aluminum lump was measured. As a result, Feo, 0035vt%, S i O
,0058wt%, and the effective distribution coefficient obtained by dividing this value by the original impurity concentration is K(Fe)−0,05, K(Si
)-0.14. Further, during the operation, the liquid level of the molten aluminum (4) was quiet and no slag was observed.

Operation example 2 In this operation example, a transparent water tank is used instead of the crucible (1) in the apparatus of Example 1, water is put in it instead of the molten aluminum (4), and a rotating cooling body (2) is used. is rotated. As a result of observing the water flow, we found that the cooling body (2
), a downward flow was generated along the molten aluminum flow downward guide section (6).

Operation example 3 This operation example was carried out using the apparatus of Example 2, except that the atmosphere above the liquid level of molten aluminum (4) in the crucible (1) was heated and maintained at 700°C. The test was carried out under the same conditions as in Operation Example 1 above. A 13 kg aluminum lump was crystallized on the circumferential surface of the cooling body (10), and when the average impurity concentration of Fe and St in this aluminum lump was measured, it was found that Fed, 0050v
t%, S i O,0070vt%, and the effective partition coefficients are K(Fe)-0,07, K(Si)-0,1
It was 7. Further, during the operation, the liquid level of the molten aluminum (4) was quiet and no slag was observed.

Comparative operation example 1 This operation example was carried out using a conventional device, and the molten aluminum (4) in the rotary cooling body (30)
The outer diameter of the portion in contact with the liquid surface was set to 150IIll11. Then, in the crucible (1), Fe0.07wt
%, SiO, molten aluminum containing 04 wt% (
4) was added and kept heated at 670°C. Then,
The rotary cooling body (30) is immersed in molten aluminum (4), and the rotation speed is 40 O while supplying cooling fluid into the inside of the rotary cooling body (30).
Rotated at rpm. After performing this operation for 30 minutes, the rotation of the cooling body (30) was stopped and the cooling body (30) was raised. A 10 kg aluminum lump was crystallized on the circumferential surface of the cooling body (30). Thereafter, the aluminum lump crystallized on the circumferential surface of the cooling body (30) was removed, and the average impurity concentration of Fe and Si in the aluminum lump was measured. As a result, Fed, 0070wt%, S i 0,008
8wt%, and its effective partition coefficient is K (Fe)-0
, 1, K(Si)-0,21. Also, during operation,
At the surface of the molten aluminum (4), intense molten metal scattering occurred, and a large amount of slag was generated. This slag adhered to the inner peripheral surface of the crucible (1) above the liquid level and became an obstacle to the continuation of the refining operation.

Comparative Operation Example 2 This operation example is the same as the Upper Period Comparative Operation Example 1, except that a rotary cooling body with the same diameter over the entire length is used instead of a rotary cooling body that tapers downward from the upper end. It was conducted under similar conditions. The average impurity concentration of Fe and St in the aluminum lump crystallized on the circumferential surface of the cooling body is
O,0065wt%, Sin,0081wt%,
This effective partition coefficient is K (Fe) = 0.09, K (S
1)=0.19. In addition, at the beginning of the operation, the turbulence of the liquid level was less than in Comparative Operation Example 1, but as the operation continued and the refined aluminum lump grew larger, the turbulence of the liquid level became larger and a large amount of slag was generated. did.

Effects of the Invention According to the rotary cooling body for a high-purity metal manufacturing apparatus of the present invention, the upper part of the portion located below the molten metal surface serves as the molten metal flow downward guide part, and the molten metal flow downward guide part has a shape that expands downward. Therefore, in the vicinity of this rotary cooling body, a downward flow is generated near the liquid surface along the molten metal flow downward guide section. Therefore, the occurrence of ripples on the liquid surface, scattering of molten metal, etc., is prevented, and as a result, A/203, which occurs as a result of the reaction between oxygen in the air and aluminum, is prevented.
The amount of slag consisting of is reduced, and problems caused by the generation of a large amount of slag are prevented.

[Brief explanation of the drawing]

FIG. 1 is a vertical sectional view showing Embodiment 1 of the invention, FIG. 2 is a vertical sectional view showing Embodiment 2 of the invention, FIG. 3 is a vertical sectional view showing Embodiment 3 of the invention, and FIG. The figure is a vertical sectional view showing Embodiment 4 of the present invention, FIG. 5 is a vertical sectional view showing Embodiment 5 of this invention, FIG. FIG. 3 is a vertical sectional view showing a conventional example. (1) (IA) ~ (ID)... Crucible, (2) (
10) (11) (15)... Rotary cooling body, (4)
... Molten aluminum, (6) (12) (1B) ...
- Molten aluminum flow downward guide section. Applicant for the above patent: Showa Aluminum Co., Ltd. Figure 1 Figure 2 4 Third Trap 4 Figure 4 Part 6 Figure 7 March 25, 1988 1. Display of the case 1986 Patent Application No. 313247 2, Q Ming's name Metal IIT rotary cooling body for equipment 36 Amendment to the case Relationship to the case Patent applicant 4 agent Showa Year Month Day 6 Increased due to amendment Contents of amendment to the number of inventions (1) “For example,” from page 2, line 1 to page 4, line 15 of the specification
There is... ] should be corrected as follows. "For example, there is a known method of refining aluminum that contains impurities that form eutectic with aluminum to a higher purity by utilizing the principle of segregation solidification. The method according to the patent application is that after the aluminum to be purified is melted, this molten aluminum is placed in a crucible and is always heated and maintained at a temperature exceeding its solidification temperature. A hollow rotary cooling body with a tapered cylindrical shape tapered downward is immersed in the cooling body, and cooling fluid is fed into this cooling body to maintain its surface temperature below the above-mentioned solidification temperature while rotating this cooling body. By dispersing and mixing the impurities discharged near the solidification interface during crystallization on the outer peripheral surface of the cooling body into the entire liquid phase, the thickness of the impurity concentrated layer near the solidification interface in the liquid phase is reduced, and as a result, There is a method of refining aluminum by crystallizing highly pure aluminum from the circumferential surface of the cooling body while increasing the temperature gradient in the liquid phase in the impurity-concentrated layer (see Japanese Patent Publication No. 3385/1985). )
. In the above method, in order to reduce the thickness of the impurity-concentrated layer near the solidification interface in the liquid phase and increase the temperature gradient as a result and improve the purification efficiency, the relative speed between the cooling body and the molten aluminum must be One of the conditions is to increase . However, as the cooling body rotates, the molten aluminum also flows in the same direction as the rotational direction of the cooling body, creating a vortex, so there is a limit to the increase in the relative speed, and there is also a limit to the improvement in refining efficiency. Moreover, if the number of revolutions of the cooling body is increased, centrifugal force increases, making it difficult for crystallized high-purity aluminum to adhere to the circumferential surface of the cooling body, resulting in a decrease in productivity. Additionally, when the rotational speed of the cooling body is increased, the area around the cooling body acts to draw in molten aluminum, air is drawn into the molten aluminum, and this air and aluminum react, producing a large amount of slag consisting of Al2O2. occurs in Moreover, since the cooling body used in the above-mentioned conventional method has a tapered cylindrical shape that tapers downward from the upper end, when it is rotated, the circumferential speeds of the upper and lower parts will be different. The circumferential speed at the top becomes larger than the circumferential speed at the bottom, creating a flow with an upward velocity component in the molten aluminum.As a result, the surface of the molten aluminum ripples and air is drawn into the molten aluminum. This air and aluminum react to form A.
A large amount of slag consisting of 12o3 is generated. Therefore, sludge removal work is required, and the sludge scatters and adheres to the inner surface of the crucible, impeding the work. Furthermore, a large amount of slag is generated, which may reduce purification efficiency. The above-mentioned ripples become more likely to occur after aluminum lumps begin to crystallize on the circumferential surface of the rotary cooling body. The applicant also proposed that a plurality of baffles for reducing the flow rate of molten aluminum be provided at predetermined intervals in the circumferential direction on the inner peripheral surface of the crucible in order to reduce the flow rate of the vortex flow of the molten aluminum. (Refer to Utility Model Publication No. 61-38912). In this case, the relative speed between the cooling body and molten aluminum can be increased without increasing the rotational speed of the cooling body so much, and the refining efficiency can be further improved. However, the presence of the baffle causes the flow velocity of the molten aluminum to differ locally, with the result that the molten aluminum has an upward velocity component near the top of the section of the cooling body that is below the liquid surface. More flow will occur. Therefore, the surface of the molten aluminum ripples more violently, and the adverse effects of the ripples become more severe. ” (2) “At this time...” on page 8, lines 15-20 of the same book.
... Therefore, "at this time, the circumferential speed of the cooling body (2) differs in each part, and in the vicinity of the cooling body (2),
An upward flow of molten aluminum (4) occurs along a portion below the maximum diameter portion (2a);
) A downward flow as shown by the arrow (A) in FIG. 1 occurs along the molten aluminum flow downward guide section (6) above the point (6). In other words, in the part below the maximum diameter part (2a), the circumferential velocity at the upper part is higher than the circumferential velocity at the lower part, and a flow with an upward velocity component is generated in the molten aluminum (4), and the maximum diameter In the portion above the portion (2a), the circumferential speed in the upper portion is smaller than the circumferential speed in the lower portion, and a flow having a downward velocity component is generated in the molten aluminum (4). Therefore,” I am corrected. (3) Add the following sentence between lines 3 and 4 on page 9 of the same book. "In the above, the molten aluminum flow downward guide section (6
) is covered with the heat insulating material (7), the high-purity aluminum lump (+) crystallizes only on the outer peripheral surface of the lower sandwiched portion below the maximum diameter portion (2a). Therefore, when collecting the high-purity aluminum lump (1), it can be easily removed from the outer circumferential surface of the cooling body (2) by scraping downward or the like. In addition, aluminum ingot (1
) is sold only on the outer peripheral surface of the lower sandwiched part below the maximum diameter part (2a), so the aluminum lump (1
) has higher purity than in the case where it crystallizes not only on the outer circumferential surface of the lower sandwiched portion but also on the outer circumferential surface of the molten aluminum flow downward guide portion (6) above the maximum diameter portion (2a). There is. That is, near the liquid surface, the temperature of the molten aluminum (4) is lower than that of other parts due to the influence of the atmospheric temperature, and the temperature of the molten aluminum (4) is lower than that of other parts, and the temperature of the molten aluminum (4) is lower than that of other parts, and the temperature of the molten aluminum (4) is lower than that of the other parts.
This is because the crystallization rate on the outer circumferential surface of the upper portion than the other portions may be faster than that of the other portions, and the aluminum purity of the obtained lump (+) may decrease. (4) "Finally," and "melt" in line 4 on page 11 of the same book.
[The circumferential speeds of the upper and lower parts of the cylindrical part (lla) become equal, and the flow of molten aluminum around it is balanced. Therefore, the molten aluminum (4
) flows are prevented from occurring. Moreover, since the circumferential speed at the lower part of the curved enlarged part (llb> is higher than that at the upper part, a flow with a downward velocity component is generated in the molten aluminum (4) in the vicinity thereof. As a result, the molten aluminum (4) Add “” to aluminum (4). (5) “Finally,” and “melting” on page 12, line 9 of the same book.
``In the same manner as in Example 1 above'' is added between. (6) "Conventional example" on page 18, line 13 of the same book is corrected to "shown in Figure 7." In line 14 of the same page, the phrase ``It is a thing'' is replaced with ``It is a thing.'' This device has a rotary cooling body (3o) immersed in molten aluminum (4) in a crucible (1) that moves downward from the top end. It has a tapered shape that gradually becomes thinner.
I am corrected. (near) In the same book, page 20, line 18, between "produces" and "therefore", it says, "In other words, when this is rotated, the circumferential speeds of the upper and lower parts will be different, and the molten metal flow in the downward guide section will be The circumferential velocity of the upper part becomes smaller than the circumferential velocity of the lower part, and a flow with a downward velocity component is generated in the molten metal." (8) "Conventional example" on page 21, line 11 of the same book is corrected to "apparatus used for comparison operation example."that's all

Claims (1)

[Claims] Consisting of a crucible and a rotating cooling body that can move up and down, the rotating cooling body is immersed in the molten metal placed in the crucible, and as the rotating cooling body rotates, metal with higher purity is crystallized from its surrounding surface. A rotary cooling body used in a metal refining device, in which the upper part of the portion located below the molten metal surface serves as a molten metal flow downward guide portion, and the molten metal flow downward guide portion has a shape that spreads downward. Rotating cooling body.