Rotor mechanism for melt purification, refining system and purification method

Abstract

The invention discloses a rotor mechanism for melt purification, a refining system and a purification method.The rotor mechanism comprises a rotating rod and a rotor fixedly arranged on the rotating rod, and the rotating rod is provided with a first air inlet channel used for continuous air inlet and refining agent powder conveying and a second air inlet channel used for pulse air inlet; a gas-liquid mixing chamber, an inlet channel communicated with the gas-liquid mixing chamber and allowing melt to enter, a first outlet channel communicated with the gas-liquid mixing chamber and allowing gas-liquid mixed melt to flow out into the melt, and a second outlet channel allowing pulse inlet gas to flow out into the melt are arranged in the rotor, and the first gas inlet channel is communicated with the gas-liquid mixing chamber; and the second air inlet channel is communicated with the second outlet channel. The rotor mechanism can realize continuous air intake and pulse air intake, on one hand, the rotating speed of the rotor can be reduced, the melt liquid level is more stable, the phenomena of hydrogen absorption and bubble combination are reduced, and the content of an involved surface oxide film is reduced; on the other hand, bubbles sprayed into the melt can reach the micron level, and slag inclusion of different sizes can be removed.

Description

Technical Field

[0001] The invention relates to the technical field of metallurgical equipment, and in particular to a rotor mechanism for melt purification, a refining system and a purification method. Background Art

[0002] In recent years, with the development of aerospace and rail transportation, the requirements for energy conservation and emission reduction have become increasingly stringent, and lightweight and high-strength non-ferrous metal alloys have gained increasing favor. Non-ferrous metal alloy parts are not limited to external parts, but are increasingly important load-bearing structural parts. The demand for high-strength, high-toughness, corrosion-resistant, fatigue-resistant and other high-damage-tolerance alloys is becoming more urgent. Melting is a key step in the production of parts, so the requirements for melt purity are also more stringent.

[0003] As we all know, there are inevitably gases and various inclusions in the melt. The existing smelting process usually includes the following steps:

[0004] 1) Removal of impurities: The presence of non-metallic inclusions, such as oxides, carbides and borides, in solidified metals will have an adverse effect on the physical and mechanical properties of the metal. Refining agents are often added. The ability of refining agents to remove impurities is determined by the refining agent's adsorption and dissolution of oxide inclusions in the melt and the chemical reaction between them.

[0005] 2) Degassing: The presence of dissolved gas in molten metal can cause defects in the product and may reduce its mechanical properties. For example, defects are introduced in castings and forged products made of aluminum or its alloys. The solubility of hydrogen in molten aluminum is high, which increases with the increase of melt temperature, but the solubility in solid aluminum is very low. Therefore, when aluminum solidifies, hydrogen is discharged, causing pores in the casting. The rotary injection method is currently the most effective for dehydrogenation. Inert gases such as Ar and N2 are used to form bubbles through the rotor. The hydrogen in the melt diffuses into these bubbles under the action of the partial pressure difference and is discharged as the bubbles float up, achieving the purpose of dehydrogenation.

[0006] 3) Grain refiners and modifiers. The grain size of the casting alloy depends on the number of nuclei present when the liquid metal begins to solidify and the cooling rate. Faster cooling rates usually 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 structure and properties of the alloy. Modification improves the alloy's resistance to hot tearing, improves the alloy's filling characteristics, and reduces shrinkage.

[0007] In the current industry, the widely used method is to purify the melt by rotating the rotor mechanism to spray gas combined with adding refining agents to the melt surface. Some rotor mechanisms in the prior art have the following problems: the bubble size is not small enough and does not reach the micron level; the rotor speed is high, which easily causes the melt to churn and produce air suction; it also reduces the pressure in the center area of ​​the melt and produces bubble fusion, all of which seriously reduce the refining effect. Some rotor mechanisms also have the problem of long melt purification time and low efficiency. In addition, when the rotor mechanism is made of graphite, there is also the problem of short service life. Summary of the invention

[0008] The object of the present invention is to provide a rotor mechanism for melt purification with better melt purification effect and longer service life in view of the deficiencies in the prior art.

[0009] In order to achieve the above object, the technical solution adopted by the present invention is:

[0010] A rotor mechanism for melt purification comprises a rotating rod and a rotor fixedly arranged at the lower end of the rotating rod, the rotating rod is provided with a first air inlet channel for continuously feeding air and conveying refining agent powder into the melt and a second air inlet channel for pulsed air feeding into the melt, and the frequency of the pulsed air feeding can be adjusted, the rotor is provided with a gas-liquid mixing chamber, an inlet channel connected with the gas-liquid mixing chamber for the melt to enter the gas-liquid mixing chamber, a first outlet channel connected with the gas-liquid mixing chamber for the gas-liquid mixed melt to flow out of the gas-liquid mixing chamber into the melt, and a second outlet channel for the pulsed air to flow out into the melt, the first air inlet channel is connected with the gas-liquid mixing chamber, and the second air inlet channel is connected with the second outlet channel.

[0011] In some embodiments, the first air inlet channel is located in the middle of the rotating rod, and a plurality of the second air inlet channels are provided, and the plurality of the second air inlet channels are respectively arranged around the periphery of the first air inlet 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 a spacing area between the first impeller and the second impeller and fixedly disposed with the first impeller and the second impeller, 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 surface of the second impeller; and the outlet end of the inlet channel is connected to 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 of the first outlet channels.

[0014] In some embodiments, the first outlet channel has an inlet end connected to 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 of the first outlet channel.

[0015] In some embodiments, the first outlet channel includes a first side wall disposed on one of the partitions and a second side wall disposed on another adjacent partition, the second side wall being an inclined surface extending obliquely from the inside to the outside in a direction away from the first side wall, and the second side wall is located behind the rotor in a rotation direction, and the inclination angle of the second side wall is 8°-15°.

[0016] In some embodiments, the first side wall is arc-shaped, and the radius of the arc is half of the height of the partition in the up-down direction.

[0017] In some embodiments, the inlet channel and the gas-liquid mixing chamber are both in the shape of a cone with a larger bottom and a smaller top, the inlet channel and the gas-liquid mixing chamber have the same taper, the small end of the inlet channel has the same diameter as the large end of the gas-liquid mixing chamber, and the inclination angle 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 arranged on the first impeller, the inlet end of the second outlet channel is connected to the second air inlet 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 air inlet channel are arranged in a one-to-one correspondence.

[0019] In some embodiments, the first impeller is provided with a plurality of first protrusions spaced apart along the circumferential direction, and the second impeller is provided with a plurality of second protrusions spaced apart along the circumferential direction, 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 partition in the circumferential direction.

[0020] In some embodiments, the upper surface of the first impeller is a conical surface whose diameter 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 one of the above items, and further comprising:

[0022] A crucible for placing a melt, wherein the rotor mechanism extends into the crucible and is rotatable relative to the crucible;

[0023] Gas supply device;

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

[0025] A driving device, disposed on the connecting seat and connected to the rotating rod, so as to drive the rotor mechanism to rotate;

[0026] a first gas pipeline, one end of which is connected to the gas supply device, and the other end of which is connected to the first gas inlet channel through the connecting seat;

[0027] a second gas pipeline, one end of which is connected to the gas supply device, and the other end of which is connected to the second gas inlet channel through the connecting seat;

[0028] A pulse generating device is arranged on the second gas pipeline.

[0029] In some embodiments, the bottom of the crucible is spherical, the height of the rotor bottom from the maximum diameter position 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.

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

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

[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 rotating rod of the present invention is provided with a first air inlet channel and a second air inlet channel at the same time. The first air inlet channel is for continuous air inlet, and the second air inlet channel is for pulse air inlet. The pressure at the gas outlet can be increased by coupling the continuous air inlet and the pulse air inlet. On the one hand, the rotor speed can be reduced, making the melt surface more stable, reducing hydrogen absorption and bubble formation, and at the same time, the stable melt surface leads to a significant reduction in the content of the surface oxide film involved. On the other hand, the bubbles injected into the melt can reach the micron level, which is composed of micron-level and millimeter-level bubbles, so that slag inclusions of different sizes can be removed.

[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, making the bubbles dispersed more evenly, thereby improving the purification effect.

[0035] (3) The present invention can add refining agent powder to the melt through the first air inlet channel, and the refining agent powder is initially dispersed in the gas-liquid mixing chamber and then sprayed into the melt. In the prior art, the refining agent powder is directly added to the surface of the melt, and the refining agent powder is introduced into the melt through the vortex, and then diffused to the surrounding of the rotor, and the modified substance is dispersed to the entire area of ​​the melt through the rotation of the rotor. Compared with the prior art, the method of adding refining agent powder in the present invention can, on the one hand, directly transport the powder to the surrounding of the rotor, which is more efficient, and the modified substance is more evenly dispersed in the melt, which increases the contact probability between the refining agent powder and inclusions, so that even small-sized inclusions can be removed; on the other hand, since the generation of surface vortices is not required, the surface oxide film remains intact to avoid being drawn into the melt. Moreover, since inclusions and gases often coexist, the removal of inclusions is also conducive to further reducing the hydrogen content of the gas.

[0036] (4) The air intake of the second air intake passage in the present invention can reduce the temperature at the first air intake passage, which can prevent the refining agent powder from melting and blocking the first air intake passage, and can also extend the service life of the rotor.

[0037] After the melt is refined by the rotor mechanism of the present invention, the final hydrogen content of the melt is only (0.05-0.08) ml / 100g. BRIEF DESCRIPTION OF THE DRAWINGS

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

[0039] Attached Figure 2 This is the second three-dimensional schematic diagram of the rotor mechanism for melt purification of this embodiment;

[0040] Attached Figure 3 Schematic top view of the rotor mechanism for melt purification of this embodiment;

[0041] Attached Figure 4 For attachment Figure 3 A schematic cross-sectional view along line AA;

[0042] Attached Figure 5 This is a three-dimensional schematic diagram of the rotor of this embodiment without the first impeller;

[0043] Attached Figure 6 This is a top view of the rotor of this embodiment without the first impeller;

[0044] Attached Figure 7 For attachment Figure 6A schematic cross-sectional view along line AA;

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

[0046] Among them: 1. rotating rod; 11. first air inlet channel; 12. second air inlet channel; 2. rotor; 21. first impeller; 211. second outlet channel; 212. first convex portion; 22. second impeller; 221. inlet channel; 222. second convex portion; 23. partition; 231. gas-liquid mixing chamber; 232. first outlet channel; 232a. first side wall; 232b. second side wall; 301. crucible; 302. gas supply device; 303. connecting seat; 304. driving device; 305. first gas pipeline; 306. second gas pipeline; 307. pulse generating device; 308. total gas pipeline; 309. pressure reducing valve; 310. flow valve. DETAILED DESCRIPTION

[0047] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0048] In the description of the present invention, it should be noted that the directions or positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like are based on the directions or positional relationships shown in the accompanying drawings, such as Figure 4 In the figure, the left side direction is "left", the right side direction is "right", the upper side direction is "up", the lower side direction is "down", and the directions perpendicular to the paper plane in the figure are "front" and "back", which are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0049] like Figure 1 to Figure 4 As shown, the rotor mechanism for melt purification of the present invention comprises a rotating rod 1 and a rotor 2. The rotating rod 1 extends in the up-down direction, and the rotating rod 2 is fixedly arranged at the lower end of the rotating rod 1. In this embodiment, the lower end of the rotating rod 1 is connected to the rotor 2 by a thread.

[0050] The rotating rod 1 is provided with a first air inlet channel 11 and a second air inlet channel 12. The first air inlet channel 11 is used to continuously inlet inert gas into the melt, and the first air inlet channel 11 can also be used to transport refining agent powder into the melt. The second air inlet channel 12 allows inert gas to be pulsed into the melt, and the gas in the second air inlet channel 12 can also cool the first air inlet channel 11. The first air inlet channel 11 and the second air inlet channel 12 both extend in the up-down 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 , so that the pulse air intake can not only meet the melt purification requirements, but also have a good cooling effect on the first air intake channel 11 .

[0052] In this embodiment, the first air inlet channel 11 is arranged at the center of the rotating rod 1, and a plurality of second air inlet channels 12 are arranged, and the plurality of second air inlet channels 12 are respectively arranged around the periphery of the first air inlet channel 11. In this embodiment, four second air inlet channels 12 are arranged, and the four second air inlet channels 12 are evenly distributed around the periphery of the first air inlet channel 11. This arrangement can increase the air intake amount of the pulse air intake, improve the melt purification effect, and at the same time, have a better cooling effect on the first air inlet channel 11.

[0053] The rotating rod 1 can be made of graphite. When the rotating rod 1 is made of graphite, the first air intake pipe 11 can be cooled by the air intake in the second air intake pipe 12, so that the refining agent powder in the first air intake pipe 11 can be prevented from melting and adhering to the pipe wall of the first air intake pipe 11 due to the temperature increase, thereby blocking the outlet of the first air intake pipe 11. At the same time, the rotating rod 1 can be prevented from being worn and peeled off due to high-temperature oxidation, erosion of the slag layer, 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 to 7As shown, a gas-liquid mixing chamber 231, an inlet channel 221, a first outlet channel 232 and a second outlet channel 211 are respectively provided in the rotor 2. The gas-liquid mixing chamber 231 is provided at the center of the rotor 2, and the first inlet channel 11 is communicated with the gas-liquid mixing chamber 231 so as to allow the inert gas to be continuously introduced into the gas-liquid mixing chamber 231. The inlet channel 221 is communicated with the gas-liquid mixing chamber 231 so as to allow the melt to enter the gas-liquid mixing chamber 231. The inert gas in the gas-liquid mixing chamber 231 is mixed with the melt to form a gas-liquid mixed melt. The first outlet channel 232 is communicated with the gas-liquid mixing chamber 231 so as to allow the gas-liquid mixed melt to flow out of the gas-liquid mixing chamber 231 and enter the melt. The second inlet channel 12 is communicated with the second outlet channel 211 so as to allow the 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 rotating rod 1. The second impeller 22 is arranged below the first impeller 21. The connecting assembly is arranged in the interval area between the first impeller 21 and the second impeller 22, and its upper and lower ends are respectively fixedly arranged on the first impeller 21 and the second impeller 22. Specifically, the connecting assembly includes a plurality of partitions 23 arranged at intervals along the circumferential direction, and the upper and lower ends of each partition 23 are respectively fixedly arranged on the first impeller 21 and the second impeller 22.

[0057] The gas-liquid mixing chamber 231 is arranged at the center of the connecting assembly, that is, the inner peripheral surface of each partition 23 forms the gas-liquid mixing chamber 231 .

[0058] like Figure 5 and Figure 6As shown, the interval between each two adjacent partitions 23 in the circumferential direction forms a first outlet channel 232. The first outlet channel 232 has an inlet end and an outlet end, the inlet end is connected to the gas-liquid mixing chamber 231, and the outlet end is located on the outer peripheral surface of the rotor 2. Specifically, the first outlet channel 232 includes a first side wall 232a and a second side wall 232b that are arranged opposite to each other, the first side wall 232a is arranged on one partition 23, the second side wall 232b is arranged on another partition 23 adjacent thereto, and the second side wall 232b is an inclined surface that extends obliquely from the inside to the outside in a direction away from the first side wall 232. Preferably, the inclination angle α of the second side wall 232b is 8°-15°, and the second side wall 232b is located at the rear of the rotation direction of the rotor 2. As a result, the cross-sectional area of ​​the first outlet channel 232 gradually increases from the inlet end of the first outlet channel 232 to the outlet end, that is, the first outlet channel 232 is in a bell-mouth shape. When the gas-liquid mixed melt flows out from the first outlet channel 232, the first side wall 232b can exert a force on the gas-liquid mixed melt obliquely forward toward the outside of the rotor 2, so that the gas-liquid mixed melt can be sprayed over a wider range along the first side wall 232b, can be mixed with the melt outside the rotor 2 more quickly, and can make the bubble dispersion more uniform, thereby improving the purification effect.

[0059] The first side wall 232 a is arc-shaped, and the radius of the arc is half the height of the partition 23 in the up-down direction.

[0060] The inlet channel 221 is disposed on the second impeller 22 , the inlet end of the inlet channel 221 is located at the lower end surface of the second impeller 22 , and the outlet end of the inlet channel 221 is communicated with the gas-liquid mixing chamber 231 .

[0061] like Figure 4 and Figure 7 As shown, the inlet channel 221 and the gas-liquid mixing chamber 231 are both in the shape of a cone with a larger bottom and a smaller top. The inlet channel 221 and the gas-liquid mixing chamber 231 have the same taper, and preferably, the angle β of the inlet channel 221 and the gas-liquid mixing chamber 231 relative to the central axis of the rotor 2 is 5°-10°. The small end of the inlet channel 221 and the large end of the gas-liquid mixing chamber 231 have the same diameter.

[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 the transmission of pressure, so that the flow rate of the gas-liquid mixed melt ejected through the first outlet channel 232 is faster, thereby making the bubbles dispersed more evenly.

[0063] In this embodiment, the second outlet channel 211 is arranged on the first impeller 21, and the second outlet channel 211 is arranged one-to-one 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 peripheral surface of the first impeller 21. This arrangement makes the structure of the rotor 2 simple. In this embodiment, the diameter of the second outlet channel 211 is 2 mm.

[0064] Of course, the second outlet channel 211 may also be disposed on the second impeller 22 or the partition 23 .

[0065] The first impeller 21 is provided with a plurality of first protrusions 212 at intervals along the circumferential direction, and the second impeller 22 is provided with a plurality of second protrusions 222 at intervals along the circumferential direction. The first protrusions 212 and the second protrusions 222 are provided in a one-to-one correspondence, and the first protrusions 212 and the second protrusions 222 correspond to the positions of the partitions 23 in the circumferential direction. In this embodiment, four first protrusions 212, four second protrusions 222 and four partitions 23 are provided in a one-to-one correspondence.

[0066] The upper surface of the first impeller 21 may be a plane. Figure 1 and Figure 4 The upper surface of the first impeller 21 may also be configured as a conical surface with a diameter gradually increasing from top to bottom, such as Figure 8 Such an arrangement can reduce the generation of vortices on the melt surface, thereby reducing the content of the surface oxide film involved.

[0067] The rotor 2 may 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, so that the flow pattern of the melt is more of an axial flow, strengthening the upward and downward circulation of the melt. At the same time, combined with part of the radial flow, the gas-liquid concentration cloud can be dispersed rapidly for a second time, which can reduce the generation of invalid tangential flow and avoid the generation of surface vortex.

[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 generating device 307 and a rotor mechanism.

[0070] The crucible 301 is used to place the melt, and the crucible 301 ensures that the melt is maintained at a certain temperature. The lower part of the rotor mechanism extends into the crucible 301 and can be rotatably arranged relative to the crucible 301. The bottom of the crucible 301 is spherical, which can reduce the generation of flow dead zones. The height of the bottom of the rotor 2 from the maximum diameter position 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 arranged on the connecting seat 303. The first gas pipeline 305 and the second gas pipeline 306 are arranged in parallel on 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 gas inlet channel 11 through the connecting seat 303, and the second gas pipeline 306 is connected to the second gas inlet channel 12 through the connecting seat 303, so that the inert gas is provided to the first gas inlet channel 11 and the second gas inlet channel 12 through the gas supply device 302.

[0072] The main gas pipeline 308 is provided with a pressure reducing valve 309 so as to adjust the pressure of the gas entering the first gas pipeline 305 and the second gas pipeline 306 .

[0073] The pulse generator 307 is arranged on the second gas pipeline 306. The frequency of the pulse generator 307 is adjustable. The inert gas is converted into a pulse gas of a certain frequency after passing through the pulse generator device 3 and flows into the second air inlet channel 12. A flow valve 310 is also arranged 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 air inlet channel 12 can be adjusted.

[0074] The first gas pipeline 305 is provided with a pressure regulating valve 309 and a flow valve 310 in sequence, so as to adjust the flow and pressure of the gas continuously entering the first air inlet channel 11 .

[0075] The driving device 304 is disposed 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] After the inert gas in the gas supply device 302 passes through the pressure reducing valve 309, the gas pressure is adjusted, 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 a pulse gas of a certain frequency through the pulse generator device 307, passes through the flow valve 310, enters the connecting seat 303, and enters the second gas inlet 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 enters the first gas inlet channel 11. The driving device 304 drives the rotating rod 1 to drive the rotor 2 to rotate in the crucible 301.

[0078] The rotor 2 rotates in the crucible 301 to suck the melt in the crucible 301 from the inlet channel 221 into the gas-liquid mixing chamber 231. The inert gas is continuously blown into the gas-liquid mixing chamber 231 from the first gas inlet channel 11, mixed with the melt in the gas-liquid mixing chamber 231 to form a gas-liquid mixed melt, and blown out from the first outlet channel 232 into the melt in the crucible 301. The pulsed inert gas is blown from the second gas inlet channel 12 through the second outlet channel 211 into the melt in the crucible 301. Driven by the rotating rotor 2, the gas-liquid mixed melt ejected through the first outlet channel 232 moves fully in the axial and radial directions, and, combined with the micron-level bubbles ejected from the second outlet channel 211, fully interacts with the gas and slag in the melt to achieve the purpose of refining the melt.

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

[0080] The present invention provides refining data under several working conditions.

[0081] Example 1: The speed of the rotor 2 is 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 pipeline 12 is 2 mm, and the hydrogen content of the melt after purification is 0.08 ml / 100 gAl.

[0082] Example 2: The speed of the rotor 2 is 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 pipeline 12 is 1 mm, and the hydrogen content of the melt after purification is 0.07 ml / 100 gAl.

[0083] Example 3: The speed of the rotor 2 is 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 pipeline 12 is 0.5 mm, and the hydrogen content of the melt after purification is 0.05 ml / 100 gAl.

[0084] The above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with the technology to understand the content of the present invention and implement it accordingly, and they cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the protection scope of the present invention.

Claims

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

2. The rotor mechanism for melt purification according to claim 1, characterized in that: The first air inlet channel is located in the middle of the rotating rod, and a plurality of second air inlet channels are provided, and the plurality of second air inlet channels are respectively arranged around the outer periphery of the first air inlet 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 a spacing area between the first impeller and the second impeller and fixed to the first impeller and the second impeller respectively, the connecting assembly includes a plurality of partitions spaced along a circumferential direction, 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 surface of the second impeller, and the outlet end of the inlet channel is connected to 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 inlet end of the inlet channel is larger than the total cross-sectional area of ​​the inlet ends of all the first outlet channels.

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

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

7. The rotor mechanism for melt purification according to claim 6, characterized in that: The first side wall is in an arc shape, and a radius of the arc is half of a height of the partition in a vertical direction.

8. The rotor mechanism for melt purification according to claim 3, characterized in that: The inlet channel and the gas-liquid mixing chamber are both in the shape of a cone with a larger bottom and a smaller top. The inlet channel and the gas-liquid mixing chamber have the same taper, the small end of the inlet channel has the same diameter as the large end of the gas-liquid mixing chamber, and the inclination angle of the conical surfaces 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 arranged on the first impeller, the inlet end of the second outlet channel is connected with the second air inlet 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 air inlet channel are arranged in a one-to-one correspondence.

10. The rotor mechanism for melt purification according to claim 3, characterized in that: The first impeller is provided with a plurality of first protrusions at intervals along the circumferential direction, and the second impeller is provided with a plurality of second protrusions at intervals along the circumferential direction. 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 partition 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 whose diameter gradually increases from top to bottom.

12. A refining system for melt purification, characterized in that: The rotor mechanism according to any one of claims 1 to 11 further comprises: A crucible for placing a melt, wherein the rotor mechanism extends into the crucible and is rotatable relative to the crucible; Gas supply device; A connecting seat, on which the rotating rod is rotatably arranged; A driving device, disposed on the connecting seat and connected to the rotating rod, so as to drive the rotor mechanism to rotate; a first gas pipeline, one end of which is connected to the gas supply device, and the other end of which is connected to the first gas inlet channel through the connecting seat; a second gas pipeline, one end of which is connected to the gas supply device, and the other end of which is connected to the second gas inlet channel through the connecting seat; A pulse generating device is arranged on the second gas pipeline.

13. The refining system for melt purification according to claim 12, characterized in that: The bottom of the crucible is spherical, the height of the rotor bottom from the maximum diameter position 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 melt is purified by using a rotor mechanism according to any one of claims 1 to 11, wherein the purification method is as follows: the rotor mechanism rotates to suck the melt from the inlet channel into the gas-liquid mixing chamber; The inert gas is continuously blown into the gas-liquid mixing chamber from the first air inlet channel, mixed 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; the pulsed inert gas is blown out into the melt from the second air 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 gas inlet channel, and is blown out into the melt from the first outlet channel.

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