CN111197121A - Method for extracting ultra-high purity aluminum by directional solidification under induction heating - Google Patents
Method for extracting ultra-high purity aluminum by directional solidification under induction heating Download PDFInfo
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- CN111197121A CN111197121A CN201811413386.3A CN201811413386A CN111197121A CN 111197121 A CN111197121 A CN 111197121A CN 201811413386 A CN201811413386 A CN 201811413386A CN 111197121 A CN111197121 A CN 111197121A
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B9/00—General processes of refining or remelting of metals; Apparatus for electroslag or arc remelting of metals
- C22B9/02—Refining by liquating, filtering, centrifuging, distilling, or supersonic wave action including acoustic waves
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B21/00—Obtaining aluminium
- C22B21/06—Obtaining aluminium refining
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
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- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
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- Y02P10/20—Recycling
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
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Abstract
The invention relates to the technical field of aluminum extraction methods, and discloses a method for extracting ultra-high purity aluminum by directional solidification under induction heating, which comprises the steps of firstly polishing an oxide layer on the outer surface of refined aluminum to be purified, then cleaning the polished refined aluminum, then drying moisture on the outer surface of the refined aluminum, then putting the treated refined aluminum into a melting crucible, closing a furnace door, locking a furnace door safety lock, starting a vacuum pump, and vacuumizing to 10 DEG C‑1And (4) below Pa, filling argon into the furnace to an atmospheric pressure value, so that the internal pressure is balanced with the external pressure. And (3) starting a heating coil power supply, heating to 680-720 ℃ to completely melt the refined aluminum, and starting a drawing system to start drawing downwards. The method for extracting the ultra-high purity aluminum by directional solidification under induction heating has the advantages of higher purification efficiency of the aluminum material, better purification effect and more environmental protection in the processing process.
Description
Technical Field
The invention relates to the technical field of aluminum extraction methods, in particular to a method for extracting ultra-high purity aluminum by directional solidification under induction heating.
Background
The aluminium is silver white light metal, has good ductility, and its commodity is made into rod-like, sheet-like, foil-like, powder-like, strip-like and filiform, and it can form a layer of oxidation film capable of preventing metal corrosion in humid air, and the aluminium powder can be heated in air and can be fiercely combusted, and can produce dazzling white flame, and is easily dissolved in dilute sulfuric acid, nitric acid, hydrochloric acid, sodium hydroxide and potassium hydroxide solution, and is difficultly dissolved in water, so that it has important application in three important industries of aviation, building and automobile, so that it has the unique properties of aluminium and its alloy, and is greatly favourable for production and application of said new metal aluminium.
The method for extracting high-purity aluminum by utilizing segregation method is generally applied in the prior art, but the existing purification of pure aluminum has many problems, such as poor purification effect, long production period, very low production efficiency and easy secondary pollution, so that the method for extracting ultrahigh-purity aluminum by directional solidification under induction heating is provided to solve the problems.
Disclosure of Invention
Aiming at the defects of the prior art, the invention provides the method for extracting the ultra-high purity aluminum by directional solidification under induction heating, which has the advantages of high purification efficiency, environmental protection and the like, and solves the problems of low purification efficiency and environmental pollution.
The purpose of the invention is realized as follows:
a method for extracting ultra-high purity aluminum by directional solidification under induction heating is characterized by comprising the following steps: the method comprises the following steps:
(1) firstly, polishing an oxide layer on the outer surface of refined aluminum to be purified, then cleaning the polished refined aluminum, and then drying the moisture on the outer surface of the refined aluminum;
(2) putting the refined aluminum processed in the step (1) into a melting crucible, closing a furnace door, locking a furnace door safety lock, starting a vacuum pump, and vacuumizing to 10 DEG-1Below Pa, filling argon into the furnace to atmospheric pressure value to balance the internal pressure with the external pressure;
(3) turning on a heating power supply of an induction coil for heating the outer layer of the smelting crucible, electrifying and heating, heating refined aluminum to 680-720 ℃, and obtaining aluminum liquid after the refined aluminum is completely melted;
(4) heating a graphite heater on the outer layer of the heat-preserving crucible to ensure that the temperature in the heat-preserving crucible is above the melting point of the aluminum liquid before casting;
(5) pressing down the control rod, and pouring the refined aluminum liquid in the smelting crucible into a heat-preservation crucible with good heat preservation;
(6) heating a graphite heater on the outer layer of the heat-preserving crucible to ensure that the temperature in the heat-preserving crucible is above the melting point of the aluminum liquid before casting;
(7) starting a traction system of the vacuum directional solidification furnace, performing downward drawing casting through a traction rod, taking out an aluminum ingot after drawing is finished and the aluminum ingot is completely cooled, cutting off 2-3cm of the upper end of the aluminum ingot, cutting off 20% of the weight of the refined aluminum processed in the step (1) at the lower end, and obtaining a finished product with the residual part of more than 5N;
(8) and (4) repeating the steps (1) to (7) on the finished aluminum ingot to obtain the ultra-high purity aluminum with the purity of 5N5 or above.
The temperature in the melting environment of the step (3) is kept between 680 and 720 ℃.
The drawing speed in the step (7) is 10cm/h-25 cm/h.
In the step (1), the aluminum ingot with the polished surface is placed in a mixed solution of HF, HNO3 and deionized water with the mass ratio of 1: 2: 3 to be soaked for 10min, then the aluminum ingot is cleaned by the deionized water and then dried in an oven, and the temperature of the oven is set to be 250 ℃.
The invention has the following advantages:
compared with the prior art, the invention provides a method for extracting ultra-high purity aluminum by directional solidification under induction heating, which has the following beneficial effects:
(1) the method for extracting the ultra-high purity aluminum by directional solidification under induction heating comprises the steps of firstly polishing the outer surface of refined aluminum to be purified, placing an aluminum ingot with the polished surface in a mixed solution of HF, HNO3 and deionized water with the mass ratio of 1: 2: 3 for soaking for 10min, and then cleaning with the deionized water, so that an oxide layer outside the refined aluminum can be effectively removed, the purified effect of the refined aluminum is better, the temperature in a heating device is kept at 680-720 ℃, the state of the aluminum liquid can be effectively ensured, and the aluminum liquid is prevented from being solidified.
(2) According to the method for extracting the ultra-high-purity aluminum by directional solidification under induction heating, the drawing speed is 10-25 cm/h, the solidification effect of the aluminum liquid can be better by matching with a water cooling system, the aluminum liquid forms a directional temperature field, a melt body is solidified along the direction opposite to the heat flow, impurities are directionally discharged, a large amount of impurities are accumulated at the bottom of an aluminum ingot, and then the impurity layer at the bottom of the aluminum ingot is taken out.
Drawings
FIG. 1 is a schematic view of a vacuum directional solidification furnace used in the present invention, 1. a melting crucible; 2. a vacuum directional solidification furnace; 3. aluminum liquid; 4. a pressure gauge; 5. argon gas; 6. 7, insulating the crucible; 8. a cooling device; 9. a cooling water inlet; 10 a cooling water outlet; 11. and a pull rod.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
A method for extracting ultra-high purity aluminum by directional solidification under induction heating comprises the following steps:
(1) firstly, polishing an oxide layer on the outer surface of refined aluminum to be purified, then cleaning the polished refined aluminum, and then drying the moisture on the outer surface of the refined aluminum;
(2) putting the refined aluminum processed in the step (1) into a melting crucible, closing a furnace door, locking a furnace door safety lock, starting a vacuum pump, and vacuumizing to 10 DEG-1Below Pa, filling argon into the furnace to atmospheric pressure value to balance the internal pressure with the external pressure;
(3) turning on a heating power supply of an induction coil for heating the outer layer of the smelting crucible, electrifying and heating, heating refined aluminum to 680-720 ℃, and obtaining aluminum liquid after the refined aluminum is completely melted;
(4) heating a graphite heater on the outer layer of the heat-preserving crucible to ensure that the temperature in the heat-preserving crucible is above the melting point of the aluminum liquid before casting;
(5) pressing down the control rod, and pouring the refined aluminum liquid in the smelting crucible into a heat-preservation crucible with good heat preservation;
(6) heating a graphite heater on the outer layer of the heat-preserving crucible to ensure that the temperature in the heat-preserving crucible is above the melting point of the aluminum liquid before casting;
(7) starting a traction system of the vacuum directional solidification furnace, performing down-drawing casting through a traction rod, starting the traction system of the vacuum directional solidification furnace, performing down-drawing casting through the traction rod, taking out an aluminum ingot after drawing is finished and the aluminum ingot is completely cooled, cutting off 2-3cm of the upper end of the aluminum ingot, cutting off 20% of the weight of the refined aluminum processed in the step (1) at the lower end, and obtaining the rest part which is a finished product with the weight of more than 5N;
(8) and (4) repeating the steps (1) to (7) on the finished aluminum ingot to obtain the ultra-high purity aluminum with the purity of 5N5 or above.
Wherein the temperature in the melting environment in the step (3) is kept between 680 and 720 ℃.
Wherein the drawing speed in the step (4) is 10cm/h-25 cm/h.
Wherein, in the step (1), the aluminum ingot with the polished surface is placed in a mixed solution of HF, HNO3 and deionized water with the mass ratio of 1: 2: 3 to be soaked for 10min, then the aluminum ingot is cleaned by the deionized water and then dried in an oven, and the temperature of the oven is set to be 200 ℃.
Example one
A method for extracting ultra-high purity aluminum by directional solidification under induction heating comprises the following steps:
(1) firstly, polishing an oxide layer on the outer surface of refined aluminum to be purified, then cleaning the polished refined aluminum, and then drying the moisture on the outer surface of the refined aluminum;
(2) putting the refined aluminum processed in the step (1) into a melting crucible, closing a furnace door, locking a furnace door safety lock, starting a vacuum pump, and vacuumizing to 10 DEG-1Below Pa, filling argon into the furnace to atmospheric pressure value to balance the internal pressure with the external pressure;
(3) turning on a heating power supply of an induction coil for heating the outer layer of the smelting crucible, electrifying and heating, heating refined aluminum to 680 ℃, and obtaining aluminum liquid after the refined aluminum is completely melted;
(4) heating a graphite heater on the outer layer of the heat-preserving crucible to ensure that the temperature in the heat-preserving crucible is above the melting point of the aluminum liquid before casting;
(5) pressing down the control rod, and pouring the refined aluminum liquid in the smelting crucible into a heat-preservation crucible with good heat preservation;
(6) heating a graphite heater on the outer layer of the heat-preserving crucible to ensure that the temperature in the heat-preserving crucible is above the melting point of the aluminum liquid before casting;
(7) starting a traction system of the vacuum directional solidification furnace, performing downward drawing casting through a traction rod, taking out an aluminum ingot after drawing is finished and completely cooled, cutting off 2 at the upper end of the aluminum ingot, cutting off 20% of the weight of the refined aluminum processed in the step (1) at the lower end, wherein the rest part is a finished product with the drawing speed of more than 5N, and the drawing speed is 10 cm/h;
(8) and (4) repeating the steps (1) to (7) on the finished aluminum ingot to obtain the ultra-high purity aluminum with the purity of 5N5 or above.
Example two
A method for extracting ultra-high purity aluminum by directional solidification under induction heating comprises the following steps:
(1) firstly, polishing an oxide layer on the outer surface of refined aluminum to be purified, then cleaning the polished refined aluminum, and then drying the moisture on the outer surface of the refined aluminum;
(2) putting the refined aluminum processed in the step (1) into a melting crucible, closing a furnace door, locking a furnace door safety lock, starting a vacuum pump, and vacuumizing to 10 DEG-1Below Pa, filling argon into the furnace to atmospheric pressure value to balance the internal pressure with the external pressure;
(3) turning on a heating power supply of an induction coil for heating the outer layer of the smelting crucible, electrifying and heating, heating refined aluminum to 700 ℃, and obtaining aluminum liquid after the refined aluminum is completely melted;
(4) heating a graphite heater on the outer layer of the heat-preserving crucible to ensure that the temperature in the heat-preserving crucible is above the melting point of the aluminum liquid before casting;
(5) pressing down the control rod, and pouring the refined aluminum liquid in the smelting crucible into a heat-preservation crucible with good heat preservation;
(6) heating a graphite heater on the outer layer of the heat-preserving crucible to ensure that the temperature in the heat-preserving crucible is above the melting point of the aluminum liquid before casting;
(7) starting a traction system of the vacuum directional solidification furnace, performing downward drawing casting through a traction rod, taking out an aluminum ingot after drawing is finished and completely cooled, cutting off 2.5cm of the upper end of the aluminum ingot, cutting off 20% of the weight of the refined aluminum processed in the step (1) at the lower end, wherein the rest part is a finished product with the weight of more than 5N, and the drawing speed is 17.5 cm/h;
(8) and (4) repeating the steps (1) to (7) on the finished aluminum ingot to obtain the ultra-high purity aluminum with the purity of 5N5 or above.
EXAMPLE III
A method for extracting ultra-high purity aluminum by directional solidification under induction heating comprises the following steps:
(1) firstly, polishing an oxide layer on the outer surface of refined aluminum to be purified, then cleaning the polished refined aluminum, and then drying the moisture on the outer surface of the refined aluminum;
(2) putting the refined aluminum processed in the step (1) into a melting crucible, closing a furnace door, locking a furnace door safety lock, starting a vacuum pump, and vacuumizing to 10 DEG-1Below Pa, filling argon into the furnace to atmospheric pressure value to balance the internal pressure with the external pressure;
(3) turning on a heating power supply of an induction coil for heating the outer layer of the smelting crucible, electrifying and heating, heating refined aluminum to 720 ℃, and obtaining aluminum liquid after the refined aluminum is completely melted;
(4) heating a graphite heater on the outer layer of the heat-preserving crucible to ensure that the temperature in the heat-preserving crucible is above the melting point of the aluminum liquid before casting;
(5) pressing down the control rod, and pouring the refined aluminum liquid in the smelting crucible into a heat-preservation crucible with good heat preservation;
(6) heating a graphite heater on the outer layer of the heat-preserving crucible to ensure that the temperature in the heat-preserving crucible is above the melting point of the aluminum liquid before casting;
(7) starting a traction system of the vacuum directional solidification furnace, performing downward drawing casting through a traction rod, taking out an aluminum ingot after drawing is finished and completely cooled, cutting off 3cm of the upper end of the aluminum ingot, cutting off 20% of the weight of the refined aluminum processed in the step (1) at the lower end, wherein the rest part is a finished product with the drawing speed of more than 5N, and the drawing speed is 25 cm/h;
(8) and (4) repeating the steps (1) to (7) on the finished aluminum ingot to obtain the ultra-high purity aluminum with the purity of 5N5 or above.
Claims (4)
1. A method for extracting ultra-high purity aluminum by directional solidification under induction heating is characterized by comprising the following steps:
(1) firstly, polishing an oxide layer on the outer surface of refined aluminum to be purified, then cleaning the polished refined aluminum, and then drying the moisture on the outer surface of the refined aluminum;
(2) putting the refined aluminum processed in the step (1) into a melting crucible, closing a furnace door, locking a furnace door safety lock, starting a vacuum pump, and vacuumizing to 10 DEG-1Below Pa, filling argon into the furnace to atmospheric pressure value to balance the internal pressure with the external pressure;
(3) turning on a heating power supply of an induction coil for heating the outer layer of the smelting crucible, electrifying and heating, heating refined aluminum to 680-720 ℃, and obtaining aluminum liquid after the refined aluminum is completely melted;
(4) heating a graphite heater on the outer layer of the heat-preserving crucible to ensure that the temperature in the heat-preserving crucible is above the melting point of the aluminum liquid before casting;
(5) pressing down the control rod, and pouring the refined aluminum liquid in the smelting crucible into a heat-preservation crucible with good heat preservation;
(6) heating a graphite heater on the outer layer of the heat-preserving crucible to ensure that the temperature in the heat-preserving crucible is above the melting point of the aluminum liquid before casting;
(7) starting a traction system of the vacuum directional solidification furnace, performing downward drawing casting through a traction rod, taking out an aluminum ingot after drawing is finished and the aluminum ingot is completely cooled, cutting off 2-3cm of the upper end of the aluminum ingot, cutting off 20% of the weight of the refined aluminum processed in the step (1) at the lower end, and obtaining a finished product with the residual part of more than 5N;
(8) and (4) repeating the steps (1) to (7) on the finished aluminum ingot to obtain the ultra-high purity aluminum with the purity of 5N5 or above.
2. The method for directional solidification extraction of ultra-high purity aluminum under induction heating according to claim 1, wherein the temperature in the melting environment of the step (3) is maintained at 680-720 ℃.
3. The method for extracting the ultrahigh-purity aluminum through directional solidification under the induction heating of claim 1, wherein the drawing speed in the step (4) is 10cm/h-25 cm/h.
4. The method for extracting the ultrahigh-purity aluminum through directional solidification under induction heating according to claim 1, wherein in the step (1), the aluminum ingot with the polished surface is placed in a mixed solution of HF, HNO3 and deionized water with a mass ratio of 1: 2: 3 for soaking for 10min, then is cleaned by the deionized water, and is dried in an oven, and the temperature of the oven is set to be 200 ℃.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111575501A (en) * | 2020-06-24 | 2020-08-25 | 江苏金海铝业有限公司 | Method for extracting ultra-high purity aluminum by directional solidification under electromagnetic stirring |
| CN113618022A (en) * | 2021-08-09 | 2021-11-09 | 广东先导微电子科技有限公司 | Aluminum bar preparation process |
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2018
- 2018-11-16 CN CN201811413386.3A patent/CN111197121A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111575501A (en) * | 2020-06-24 | 2020-08-25 | 江苏金海铝业有限公司 | Method for extracting ultra-high purity aluminum by directional solidification under electromagnetic stirring |
| CN113618022A (en) * | 2021-08-09 | 2021-11-09 | 广东先导微电子科技有限公司 | Aluminum bar preparation process |
| CN113618022B (en) * | 2021-08-09 | 2023-02-17 | 广东先导微电子科技有限公司 | Aluminum bar preparation process |
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Application publication date: 20200526 |