A rotor mechanism, refining system and purification method for melt purification

Abstract

This invention discloses a rotor mechanism, refining system, and purification method for melt purification. The rotor mechanism includes a rotating rod and a rotor fixed on the rotating rod. The rotating rod is provided with a first air inlet channel for continuous air intake and conveying refining agent powder, and a second air inlet channel for pulsed air intake. The rotor is provided with a gas-liquid mixing chamber, an inlet channel communicating with the gas-liquid mixing chamber for the melt to enter, a first outlet channel communicating with the gas-liquid mixing chamber for the gas-liquid mixed melt to flow out into the melt, and a second outlet channel for the pulsed air intake to flow out into the melt. The first air inlet channel is connected to the gas-liquid mixing chamber, and the second air inlet channel is connected to the second outlet channel. This rotor mechanism can realize continuous air intake and pulsed air intake. On the one hand, it can reduce the rotor speed, making the melt surface more stable, reducing hydrogen absorption and bubble formation, and reducing the content of surface oxide film entrainment. On the other hand, it can make the bubbles injected into the melt reach the micron level, which can remove inclusions of different sizes.

Description

Technical Field

[0001] This invention relates to the field of metallurgical equipment technology, specifically to a rotor mechanism for melt purification, a refining system, and a purification method. Background Technology

[0002] In recent years, with the development of aerospace and rail transportation, the requirements for energy conservation and emission reduction have become increasingly stringent, leading to a growing preference for lightweight and high-strength non-ferrous metal alloys. Non-ferrous metal alloy components are no longer limited to external parts; increasingly, they serve as important load-bearing structural components. This necessitates a more urgent demand for high-strength, high-toughness, corrosion-resistant, and fatigue-resistant alloys with high damage tolerance. As smelting is a crucial step in component production, the requirements for melt purity are becoming increasingly stringent.

[0003] As is well known, gases and various inclusions are unavoidable in melts. Existing smelting processes often include the following steps:

[0004] 1) Impurity removal: The presence of non-metallic inclusions, such as oxides, carbides, and borides, in solidified metals can adversely affect their physical and mechanical properties. Refining agents are often added to remove these inclusions. The impurity removal ability of the refining agent is determined by its adsorption, dissolution, and chemical interactions with oxidized inclusions in the melt.

[0005] 2) Degassing: The presence of dissolved gases in molten metal can introduce defects into products and potentially reduce their mechanical properties. For example, it can introduce defects into castings and forgings made of aluminum or its alloys. Hydrogen has high solubility in molten aluminum, which increases with melting temperature, but its solubility in solid aluminum is very low. Therefore, hydrogen is expelled during aluminum solidification, causing porosity in the casting. Rotary jet cleaning is currently the most effective method for hydrogen removal. Using inert gases such as Ar and N2, bubbles are formed by a rotor. Hydrogen in the molten metal diffuses into these bubbles under the influence of the partial pressure difference and is expelled as the bubbles rise, thus achieving the purpose of hydrogen removal.

[0006] 3) Grain refiners and modifiers: The grain size of a casting alloy depends on the number of nuclei present when the liquid metal begins to solidify and the cooling rate. Faster cooling rates generally result in smaller grain sizes, and the addition of certain elements to the melt can provide nucleation sites for grain growth. Adding small amounts of certain modifying elements, such as sodium or strontium, can improve the alloy's microstructure and properties. Modification enhances the alloy's resistance to hot tearing, improves its filling characteristics, and reduces shrinkage porosity.

[0007] Currently, the widely used industrial method for purifying melts involves rotating a rotor mechanism to inject gas, combined with the addition of refining agents to the melt surface. However, some existing rotor mechanisms suffer from the following problems: the bubble size is not small enough to reach the micrometer level; the high rotor speed easily causes melt turbulence and gas intake; it also reduces pressure in the central region of the melt, leading to bubble aggregation, all of which severely reduce refining efficiency. Furthermore, some rotor mechanisms suffer from long melt purification times and low efficiency. Additionally, rotor mechanisms made of graphite materials also have a short service life. Summary of the Invention

[0008] The purpose of this invention is to address the shortcomings of existing technologies by providing a rotor mechanism for melt purification that offers better melt purification performance and a longer service life.

[0009] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0010] A rotor mechanism for melt purification includes a rotating rod and a rotor fixedly disposed at the lower end of the rotating rod. The rotating rod is provided with a first air intake channel for continuously introducing and conveying refining agent powder into the melt and a second air intake channel for pulsed air intake into the melt, and the frequency of the pulsed air intake is adjustable. The rotor is provided with a gas-liquid mixing chamber, an inlet channel communicating with the gas-liquid mixing chamber for the melt to enter the gas-liquid mixing chamber, a first outlet channel communicating with the gas-liquid mixing chamber for the gas-liquid mixed melt to flow out of the gas-liquid mixing chamber and into the melt, and a second outlet channel for the pulsed air intake to flow out into the melt. The first air intake channel is communicating with the gas-liquid mixing chamber, and the second air intake channel is communicating with the second outlet channel.

[0011] In some embodiments, the first air intake channel is located in the middle of the rotating rod, and multiple second air intake channels are provided, with each of the multiple second air intake channels surrounding the outer periphery of the first air intake channel.

[0012] In some embodiments, the rotor includes a first impeller, a second impeller spaced below the first impeller, and a connecting assembly disposed in the spaced region between the first and second impellers and fixedly disposed to the first and second impellers respectively. The connecting assembly includes a plurality of spacers spaced circumferentially. The gas-liquid mixing chamber is disposed at the center of the connecting assembly. The interval between each two adjacent spacers forms the first outlet channel. One end of the rotating rod is fixedly disposed on the first impeller. The inlet channel is disposed on the second impeller. The inlet end of the inlet channel is located on the lower end face of the second impeller. The outlet end of the inlet channel communicates with the gas-liquid mixing chamber.

[0013] In some embodiments, the cross-sectional area of ​​the inlet end of the inlet channel is greater than the total cross-sectional area of ​​the inlet ends of all the first outlet channels.

[0014] In some embodiments, the first outlet channel has an inlet end communicating with the gas-liquid mixing chamber and an outlet end located on the outer peripheral surface of the rotor, and the cross-sectional area of ​​the first outlet channel gradually increases from the inlet end to the outlet end.

[0015] In some embodiments, the first outlet channel includes a first sidewall disposed on one of the partitions and a second sidewall disposed on another partition adjacent thereto, the second sidewall being an inclined surface extending from the inside outward toward the direction away from the first sidewall, and the second sidewall being located behind the rotor rotation direction, the second sidewall being inclined at an angle of 8°-15°.

[0016] In some embodiments, the first sidewall is arc-shaped, and the radius of the arc is half the height of the separator in the vertical direction.

[0017] In some embodiments, both the inlet channel and the gas-liquid mixing chamber are frustoconical in shape, with the inlet channel and the gas-liquid mixing chamber having the same taper. The smaller end of the inlet channel has the same diameter as the larger end of the gas-liquid mixing chamber, and the angle of inclination of the conical surfaces of the inlet channel and the gas-liquid mixing chamber relative to the central axis is 5°-10°.

[0018] In some embodiments, the second outlet channel is disposed on the first impeller, the inlet end of the second outlet channel is connected to the second intake channel, the outlet end of the second outlet channel is located on the outer circumferential surface of the first impeller, and the second outlet channel and the second intake channel are configured in a one-to-one correspondence.

[0019] In some embodiments, the first impeller is provided with a plurality of first protrusions spaced apart circumferentially, and the second impeller is provided with a plurality of second protrusions spaced apart circumferentially. The first protrusions and the second protrusions are provided in a one-to-one correspondence, and the first protrusions and the second protrusions correspond to the positions of the separator in the circumferential direction.

[0020] In some embodiments, the upper surface of the first impeller is a conical surface with a diameter that gradually increases from top to bottom.

[0021] The present invention also provides a refining system for melt purification, comprising a rotor mechanism as described in any of the preceding claims, and further comprising:

[0022] A crucible for holding melt, the rotor mechanism extending into the crucible and rotatably positioned relative to the crucible;

[0023] Gas supply device;

[0024] A connecting seat, on which the rotating rod is rotatably mounted;

[0025] A drive device is mounted on the connecting seat and connected to the rotating rod to drive the rotor mechanism to rotate;

[0026] The first gas pipeline has one end connected to the gas supply device and the other end connected to the first air inlet channel via the connecting seat;

[0027] The second gas pipeline has one end connected to the gas supply device and the other end connected to the second air inlet channel through the connecting seat;

[0028] A pulse generator is installed on the second gas pipeline.

[0029] In some embodiments, the bottom of the crucible is spherical, the height of the bottom of the rotor from the position of the maximum diameter of the bottom of the crucible is 15mm-25mm, and the ratio of the outer diameter of the rotor to the inner diameter of the crucible at the rotor position is 0.2-0.3.

[0030] The present invention also provides a melt purification method, which uses a rotor mechanism as described in any of the above claims to purify the melt. The purification method is as follows: the rotor mechanism rotates to draw the melt from the inlet channel into the gas-liquid mixing chamber; inert gas is continuously blown into the gas-liquid mixing chamber from the first inlet channel to mix with the melt in the gas-liquid mixing chamber to form a gas-liquid mixed melt, and blown out into the melt from the first outlet channel; pulsed inert gas is blown out into the melt from the second inlet channel through the second outlet channel.

[0031] In some embodiments, refining agent powder is blown from the first inlet channel into the gas-liquid mixing chamber and blown out from the first outlet channel into the melt.

[0032] Due to the application of the above technical solution, the rotor mechanism for melt purification of the present invention has the following advantages compared with the prior art:

[0033] (1) The rotor of this invention is simultaneously provided with a first air intake channel and a second air intake channel. The first air intake channel provides continuous air intake, while the second air intake channel provides pulsed air intake. Through the coupled design of continuous and pulsed air intake, the pressure at the gas outlet can be increased. On the one hand, this can reduce the rotor speed, making the melt surface more stable and reducing hydrogen absorption and bubble formation. At the same time, the stable melt surface leads to a significant reduction in the content of surface oxide films entrained. On the other hand, it can make the bubbles injected into the melt reach the micron level, composed of a combination of micron-sized and millimeter-sized bubbles, thus removing inclusions of different sizes.

[0034] (2) The rotor of the present invention is provided with a gas-liquid mixing chamber, which allows the bubbles and the melt to be initially mixed before being sprayed into the melt, which can make the bubbles more evenly dispersed, thereby improving the purification effect.

[0035] (3) In this invention, refining agent powder can be added to the melt through the first air inlet channel. The refining agent powder is initially dispersed in the gas-liquid mixing chamber and then sprayed into the melt. In contrast, in the prior art, refining agent powder is added directly to the surface of the melt. The refining agent powder is introduced into the melt through a vortex and then diffuses to the periphery of the rotor. The rotation of the rotor disperses the modified material throughout the entire melt area. Compared with the prior art, the method of adding refining agent powder in this invention can directly transport the powder to the periphery of the rotor, which is more efficient. The modified material is more evenly dispersed in the melt, increasing the probability of contact between the refining agent powder and inclusions, so that even small inclusions can be removed. On the other hand, since the generation of surface vortices is not required, the surface oxide film remains intact, avoiding being drawn into the interior by the melt. Moreover, since inclusions and gas often coexist, the removal of inclusions is also beneficial to further reduce the hydrogen content of the gas.

[0036] (4) In this invention, the air intake of the second air intake channel can reduce the temperature at the first air intake channel. On the one hand, it can prevent the refining agent powder from melting and blocking the first air intake channel, and on the other hand, it can extend the service life of the rotor.

[0037] After refining the melt using the rotor mechanism of this invention, the final hydrogen content of the melt is only (0.05-0.08) ml / 100g. Attached Figure Description

[0038] Appendix Figure 1 This is one of the three-dimensional schematic diagrams of the rotor mechanism for melt purification in this embodiment;

[0039] Appendix Figure 2 This is the second perspective view of the rotor mechanism for melt purification in this embodiment;

[0040] Appendix Figure 3 This is a top view schematic diagram of the rotor mechanism for melt purification in this embodiment;

[0041] Appendix Figure 4 For the appendix Figure 3 sectional view along line AA;

[0042] Appendix Figure 5 This is a three-dimensional schematic diagram of the rotor after the first impeller has been removed in this embodiment;

[0043] Appendix Figure 6 This is a top view of the rotor after removing the first impeller in this embodiment;

[0044] Appendix Figure 7 For the appendix Figure 6sectional view along line AA;

[0045] Appendix Figure 8 This is a schematic diagram of the refining system for melt purification in this embodiment.

[0046] Wherein: 1. Rotor; 11. First air inlet channel; 12. Second air inlet channel; 2. Rotor; 21. First impeller; 211. Second outlet channel; 212. First protrusion; 22. Second impeller; 221. Inlet channel; 222. Second protrusion; 23. Separator; 231. Gas-liquid mixing chamber; 232. First outlet channel; 232a. First sidewall; 232b. Second sidewall; 301. Crucible; 302. Gas supply device; 303. Connecting seat; 304. Drive device; 305. First gas pipeline; 306. Second gas pipeline; 307. Pulse generator; 308. Main gas pipeline; 309. Pressure reducing valve; 310. Flow valve. Detailed Implementation

[0047] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0048] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, such as... Figure 4 In the figures, the left direction is "left," the right direction is "right," the top direction is "up," and the bottom direction is "down." The directions perpendicular to the paper are "front" and "back." This is only for the convenience of describing the invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0049] like Figures 1-4 As shown, the rotor mechanism for melt purification of the present invention includes a rotating rod 1 and a rotor 2. The rotating rod 1 extends in the vertical direction, and the rotating rod 2 is fixedly disposed at the lower end of the rotating rod 1. In this embodiment, the lower end of the rotating rod 1 is threadedly connected to the rotor 2.

[0050] The rotating rod 1 is provided with a first air intake channel 11 and a second air intake channel 12. The first air intake channel 11 is used to continuously introduce inert gas into the melt, and can also be used to convey refining agent powder into the melt. The second air intake channel 12 introduces inert gas into the melt in pulses, and the gas in the second air intake channel 12 can also cool the first air intake channel 11. Both the first air intake channel 11 and the second air intake channel 12 extend in the vertical direction.

[0051] The frequency of pulse air intake can be adjusted according to the melt purification effect and the cooling effect on the first air intake channel 11. In this way, pulse air intake can meet the needs of melt purification and also have a good cooling effect on the first air intake channel 11.

[0052] In this embodiment, the first air intake channel 11 is located at the center of the rotating rod 1, and multiple second air intake channels 12 are provided, each surrounding the outer periphery of the first air intake channel 11. In this embodiment, four second air intake channels 12 are provided, evenly distributed around the outer periphery of the first air intake channel 11. This arrangement increases the intake volume of the pulse air intake, improves the melt purification effect, and also provides a better cooling effect on the first air intake channel 11.

[0053] The rotating rod 1 can be made of graphite. When the rotating rod 1 is made of graphite, the cooling of the first air intake pipe 11 by the air intake through the second air intake pipe 12 can prevent the refining agent powder from melting and adhering to the pipe wall of the first air intake pipe 11 due to temperature rise, thus avoiding blockage of the outlet of the first air intake pipe 11. At the same time, it can also prevent the rotating rod 1 from wearing and peeling off due to high temperature oxidation, slag erosion, thermal stress, etc., thereby improving the service life of the rotating rod 1.

[0054] In this embodiment, the diameter of the first air intake pipe 11 is (8-15) mm, and the diameter of the second air intake pipe is (0.5-3) mm.

[0055] like Figures 4-7As shown, the rotor 2 is equipped with a gas-liquid mixing chamber 231, an inlet channel 221, a first outlet channel 232, and a second outlet channel 211. The gas-liquid mixing chamber 231 is located at the center of the rotor 2. The first inlet channel 11 communicates with the gas-liquid mixing chamber 231 to allow inert gas to be continuously introduced into the gas-liquid mixing chamber 231. The inlet channel 221 communicates with the gas-liquid mixing chamber 231 to allow the melt to enter the gas-liquid mixing chamber 231. The inert gas in the gas-liquid mixing chamber 231 mixes with the melt to form a gas-liquid mixed melt. The first outlet channel 232 communicates with the gas-liquid mixing chamber 231 to allow the gas-liquid mixed melt to flow out of the gas-liquid mixing chamber 231 and into the melt. The second inlet channel 12 communicates with the second outlet channel 211 to allow inert gas to be pulsed into the melt.

[0056] Specifically, the rotor 2 includes a first impeller 21, a second impeller 22, and a connecting assembly. The first impeller 21 is fixedly connected to the lower end of the rotor 1. The second impeller 22 is spaced below the first impeller 21. The connecting assembly is located in the spaced area between the first impeller 21 and the second impeller 22, with its upper and lower ends fixedly mounted on the first impeller 21 and the second impeller 22, respectively. Specifically, the connecting assembly includes a plurality of spacers 23 spaced circumferentially, with the upper and lower ends of each spacer 23 fixedly mounted on the first impeller 21 and the second impeller 22, respectively.

[0057] The gas-liquid mixing chamber 231 is located at the center of the connecting assembly, that is, the gas-liquid mixing chamber 231 is formed by the inner circumferential surfaces of each partition 23.

[0058] like Figure 5 and Figure 6As shown, the circumferential spacing between each pair of adjacent separators 23 forms a first outlet channel 232. The first outlet channel 232 has an inlet end and an outlet end. The inlet end communicates with the gas-liquid mixing chamber 231, and the outlet end is located on the outer circumferential surface of the rotor 2. Specifically, the first outlet channel 232 includes a first sidewall 232a and a second sidewall 232b disposed opposite to each other. The first sidewall 232a is disposed on one separator 23, and the second sidewall 232b is disposed on another adjacent separator 23. The second sidewall 232b is an inclined surface extending obliquely from the inside outwards away from the first sidewall 232. Preferably, the angle α of the second sidewall 232b is 8°-15°, and the second sidewall 232b is located behind the rotor 2 in the direction of rotation. This results in the cross-sectional area of ​​the first outlet channel 232 gradually increasing from the inlet end to the outlet end, i.e., the first outlet channel 232 is funnel-shaped. When the gas-liquid mixture flows out of the first outlet channel 232, the first sidewall 232b can exert a force on the gas-liquid mixture in a forward and oblique direction to the outside of the rotor 2, so that the gas-liquid mixture is sprayed out along the first sidewall 232b over a wider range, and can mix with the melt outside the rotor 2 more quickly, which can make the bubbles disperse more evenly, thereby improving the purification effect.

[0059] The first sidewall 232a is arc-shaped, and the radius of the arc is half the height of the separator 23 in the vertical direction.

[0060] The inlet channel 221 is provided on the second impeller 22. The inlet end of the inlet channel 221 is located on the lower end face of the second impeller 22, and the outlet end of the inlet channel 221 is connected to the gas-liquid mixing chamber 231.

[0061] like Figure 4 and Figure 7 As shown, both the inlet channel 221 and the gas-liquid mixing chamber 231 are frustoconical in shape, with the smaller end at the bottom and the smaller end at the top. The inlet channel 221 and the gas-liquid mixing chamber 231 have the same taper; preferably, the angle β of the inlet channel 221 and the gas-liquid mixing chamber 231's conical surfaces relative to the central axis of the rotor 2 is 5°-10°. The smaller end of the inlet channel 221 has the same diameter as the larger end of the gas-liquid mixing chamber 231.

[0062] The cross-sectional area of ​​the inlet end of the inlet channel 221 is larger than the total cross-sectional area of ​​the inlet ends of all the first outlet channels 232. This ensures pressure transmission, resulting in a faster flow rate of the gas-liquid mixture ejected through the first outlet channel 232, thus making the bubbles more evenly dispersed.

[0063] In this embodiment, the second outlet channel 211 is disposed on the first impeller 21, and the second outlet channel 211 is configured in a one-to-one correspondence with the second intake channel 12. The inlet end of each second outlet channel 211 is connected to the corresponding second intake channel 12, and the outlet end of the second outlet channel 211 is located on the outer circumferential surface of the first impeller 21. This configuration simplifies the structure of the rotor 2. In this embodiment, the diameter of the second outlet channel 211 is 2 mm.

[0064] Of course, the second outlet channel 211 can also be set on the second impeller 22 or the separator 23.

[0065] The first impeller 21 has a plurality of first protrusions 212 spaced apart circumferentially, and the second impeller 22 has a plurality of second protrusions 222 spaced apart circumferentially. The first protrusions 212 and the second protrusions 222 are arranged in a one-to-one correspondence, and the positions of the first protrusions 212 and the second protrusions 222 correspond to the positions of the separators 23 in the circumferential direction. In this embodiment, four of each of the first protrusions 212, the second protrusions 222, and the separators 23 are arranged in a one-to-one correspondence.

[0066] The upper surface of the first impeller 21 can be a plane, such as... Figure 1 and Figure 4 As shown. The upper surface of the first impeller 21 can also be configured as a conical surface with a diameter that gradually increases from top to bottom, such as... Figure 8 As shown. This configuration reduces the generation of vortices on the melt surface, thereby reducing the amount of surface oxide film entrained.

[0067] The rotor 2 can be made of graphite, that is, the first impeller 21, the second impeller 22 and the separator 23 are all made of graphite.

[0068] The rotor 2 adopts a multi-stage structure arranged along the axial direction, which makes the flow pattern of the melt more axial, enhances the circulation of the melt, and at the same time combines with a part of radial flow, which can make the gas-liquid concentration cloud disperse rapidly for a second time. This can reduce the generation of ineffective tangential flow and avoid the generation of surface vortices.

[0069] like Figure 8 As shown, the refining system for melt purification of the present invention includes a crucible 301, a gas supply device 302, a connecting seat 303, a driving device 304, a first gas pipeline 305, a second gas pipeline 306, a pulse generator 307, and a rotor mechanism.

[0070] The crucible 301 is used to hold the melt and ensures that the melt is maintained at a certain temperature. The lower part of the rotor mechanism extends into the crucible 301 and is rotatably positioned relative to the crucible 301. The bottom of the crucible 301 is spherical to reduce the generation of flow dead zones. The height of the bottom of the rotor 2 from the position of the maximum diameter of the bottom of the crucible 301 is 15mm-25mm, and the ratio of the outer diameter of the rotor 2 to the inner diameter of the crucible 301 at the position of the rotor 2 is 0.2-0.3.

[0071] The rotating rod 1 is rotatably mounted on the connecting seat 303. The first gas pipeline 305 and the second gas pipeline 306 are connected in parallel to the main gas pipeline 308 connected to the outlet of the gas supply device 302. The first gas pipeline 305 is connected to the first air intake channel 11 via the connecting seat 303, and the second gas pipeline 306 is connected to the second air intake channel 12 via the connecting seat 303, thereby providing inert gas to the first air intake channel 11 and the second air intake channel 12 through the gas supply device 302.

[0072] A pressure reducing valve 309 is installed on the main gas pipeline 308, which can adjust the gas pressure entering the first gas pipeline 305 and the second gas pipeline 306.

[0073] A pulse generator 307 is installed on the second gas pipeline 306. The frequency of the pulse generator 307 is adjustable. After passing through the pulse generator 307, the inert gas is converted into pulsed gas of a certain frequency and flows into the second intake channel 12. A flow valve 310 is also installed on the second gas pipeline 306 between the pulse generator 307 and the connecting seat 303, so that the gas flow rate of the pulse entering the second intake channel 12 can be adjusted.

[0074] A pressure regulating valve 309 and a flow valve 310 are sequentially installed on the first gas pipeline 305, so that the flow rate and pressure of the gas continuously entering the first gas inlet channel 11 can be adjusted.

[0075] The drive unit 304 is mounted on the connecting seat 303 and connected to the rotating rod 1 to drive the rotor mechanism to rotate.

[0076] The melt purification method is as follows:

[0077] The inert gas in the gas supply device 302 passes through the pressure reducing valve 309 to adjust the gas pressure, and the gas path is divided into two paths, entering the first gas pipeline 305 and the second gas pipeline 306 respectively. The inert gas in the second gas pipeline 306 is converted into pulsed gas of a certain frequency by the pulse generator device 307, passes through the flow valve 310, enters the connecting seat 303, and then enters the second air intake channel 12. The first gas pipeline 305 is a continuous gas intake, and the inert gas passes through the pressure reducing valve 309 again to adjust to a suitable gas pressure, passes through the flow valve 310, enters the connecting seat 303, and then enters the first air intake channel 11. The drive device 304 drives the rotating rod 1 to drive the rotor 2 to rotate inside the crucible 301.

[0078] Rotor 2 rotates within crucible 301, drawing the melt from crucible 301 into gas-liquid mixing chamber 231 through inlet channel 221. Inert gas is continuously blown into gas-liquid mixing chamber 231 through first inlet channel 11, mixing with the melt to form a gas-liquid mixture, which is then blown out through first outlet channel 232 into the melt within crucible 301. Pulsed inert gas is blown out through second inlet channel 12 and second outlet channel 211 into the melt within crucible 301. Driven by rotating rotor 2, the gas-liquid mixture ejected through first outlet channel 232 moves fully axially and radially, combining with micron-sized bubbles ejected through second outlet channel 211, and fully interacts with the gas and inclusions in the melt to achieve the purpose of refining the melt.

[0079] During melt purification, the rotor mechanism rotates at a speed of (200-400) r / min. The continuous gas flow rate is (15-30) L / min, and the gas pressure is (0.4-0.6) MPa. The pulse generator 307 operates at a frequency of (0-100) Hz, and the pulse inlet pressure is (0.5-0.9) MPa.

[0080] This invention provides refining data under several operating conditions.

[0081] Example 1: The rotor 2 rotates at 250 r / min, the pulse gas pressure is 0.7 MPa, the continuous gas pressure is 0.45 MPa, the gas flow rate is 20 L / min, the diameter of the second gas pipe 12 is 2 mm, and the hydrogen content of the purified melt is 0.08 ml / 100 g Al.

[0082] Example 2: The rotor 2 rotates at 350 r / min, the pulse gas pressure is 0.8 MPa, the continuous gas pressure is 0.45 MPa, the gas flow rate is 20 L / min, the diameter of the second gas pipe 12 is 1 mm, and the hydrogen content of the purified melt is 0.07 ml / 100 g Al.

[0083] Example 3: The rotor 2 rotates at 400 r / min, the pulse gas pressure is 0.9 MPa, the continuous gas pressure is 0.45 MPa, the gas flow rate is 20 L / min, the diameter of the second gas pipe 12 is 0.5 mm, and the hydrogen content of the purified melt is 0.05 ml / 100 g Al.

[0084] The above embodiments are only for illustrating the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They should not be construed as limiting the scope of protection of the present invention. All equivalent changes or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A rotor mechanism for melt purification, comprising a rotating rod and a rotor fixedly disposed at the lower end of the rotating rod, characterized in that: The rotor is provided with a first air intake channel for continuous air intake and conveying refining agent powder into the melt and a second air intake channel for pulse air intake into the melt, and the frequency of pulse air intake can be adjusted. The rotor is provided with a gas-liquid mixing chamber, an inlet channel communicating with the gas-liquid mixing chamber for the melt to enter the gas-liquid mixing chamber, a first outlet channel communicating with the gas-liquid mixing chamber for the gas-liquid mixed melt to flow out of the gas-liquid mixing chamber and into the melt, and a second outlet channel for the pulse air intake to flow out into the melt. The first air intake channel is communicating with the gas-liquid mixing chamber, and the second air intake channel is communicating with the second outlet channel.

2. The rotor mechanism for melt purification according to claim 1, characterized in that: The first air intake channel is located in the middle of the rotating rod, and multiple second air intake channels are provided, with each of the multiple second air intake channels surrounding the outer periphery of the first air intake channel.

3. The rotor mechanism for melt purification according to claim 1, characterized in that: The rotor includes a first impeller, a second impeller spaced below the first impeller, and a connecting assembly disposed in the spaced area between the first and second impellers and fixedly disposed to the first and second impellers respectively. The connecting assembly includes a plurality of partitions spaced circumferentially. The gas-liquid mixing chamber is disposed at the center of the connecting assembly. The interval between each two adjacent partitions forms the first outlet channel. One end of the rotating rod is fixedly disposed on the first impeller. The inlet channel is disposed on the second impeller. The inlet end of the inlet channel is located on the lower end face of the second impeller. The outlet end of the inlet channel communicates with the gas-liquid mixing chamber.

4. The rotor mechanism for melt purification according to claim 3, characterized in that: The cross-sectional area of ​​the entrance end of the entrance channel is greater than the total cross-sectional area of ​​the entrance ends of all the first exit channels.

5. The rotor mechanism for melt purification according to claim 3, characterized in that: The first outlet channel has an inlet end communicating with the gas-liquid mixing chamber and an outlet end located on the outer peripheral surface of the rotor. From the inlet end to the outlet end, the cross-sectional area of ​​the first outlet channel gradually increases.

6. The rotor mechanism for melt purification according to claim 3, characterized in that: The first outlet channel includes a first sidewall disposed on one of the partitions and a second sidewall disposed on another partition adjacent thereto. The second sidewall is an inclined surface extending from the inside outward in a direction away from the first sidewall, and the second sidewall is located behind the rotor rotation direction. The angle of inclination of the second sidewall is 8°-15°.

7. The rotor mechanism for melt purification according to claim 6, characterized in that: The first sidewall is arc-shaped, and the radius of the arc is half the height of the separator in the vertical direction.

8. The rotor mechanism for melt purification according to claim 3, characterized in that: Both the inlet channel and the gas-liquid mixing chamber are truncated cones, with the inlet channel being larger at the bottom and the gas-liquid mixing chamber being smaller at the top. The taper of the inlet channel and the gas-liquid mixing chamber are the same. The diameter of the smaller end of the inlet channel is the same as that of the larger end of the gas-liquid mixing chamber. The angle of inclination of the conical surface of the inlet channel and the gas-liquid mixing chamber relative to the central axis is 5°-10°.

9. The rotor mechanism for melt purification according to claim 3, characterized in that: The second outlet channel is disposed on the first impeller. The inlet end of the second outlet channel is connected to the second intake channel. The outlet end of the second outlet channel is located on the outer circumferential surface of the first impeller. The second outlet channel and the second intake channel are configured in a one-to-one correspondence.

10. The rotor mechanism for melt purification according to claim 3, characterized in that: The first impeller has a plurality of first protrusions spaced apart along the circumference, and the second impeller has a plurality of second protrusions spaced apart along the circumference. The first protrusions and the second protrusions are arranged in a one-to-one correspondence, and the first protrusions and the second protrusions correspond to the positions of the separator in the circumferential direction.

11. The rotor mechanism for melt purification according to claim 3, characterized in that: The upper surface of the first impeller is a conical surface with a diameter that gradually increases from top to bottom.

12. A refining system for melt purification, characterized in that: The rotor mechanism, as described in any one of claims 1 to 11, further includes: A crucible for holding melt, the rotor mechanism extending into the crucible and rotatably positioned relative to the crucible; Gas supply device; A connecting seat, on which the rotating rod is rotatably mounted; A drive device is mounted on the connecting seat and connected to the rotating rod to drive the rotor mechanism to rotate; The first gas pipeline has one end connected to the gas supply device and the other end connected to the first air inlet channel via the connecting seat; The second gas pipeline has one end connected to the gas supply device and the other end connected to the second air inlet channel through the connecting seat; A pulse generator is installed on the second gas pipeline.

13. The refining system for melt purification according to claim 12, characterized in that: The crucible has a spherical bottom, the distance between the bottom of the rotor and the position of the maximum diameter of the crucible bottom is 15mm-25mm, and the ratio of the outer diameter of the rotor to the inner diameter of the crucible at the rotor position is 0.2-0.

3.

14. A melt purification method, characterized in that: The rotor mechanism as described in any one of claims 1 to 11 is used to purify the melt, wherein the purification method is as follows: the rotor mechanism rotates to draw the melt from the inlet channel into the gas-liquid mixing chamber; Inert gas is continuously blown into the gas-liquid mixing chamber from the first inlet channel, where it mixes with the melt in the gas-liquid mixing chamber to form a gas-liquid mixed melt, and is blown out into the melt from the first outlet channel; pulsed inert gas is blown out into the melt from the second inlet channel through the second outlet channel.

15. The melt purification method according to claim 14, characterized in that: The refining agent powder is blown into the gas-liquid mixing chamber from the first air inlet channel and blown out into the melt from the first outlet channel.

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