Filter pressing circulation system for preparing low-oxygen iron-nickel alloy powder and preparation method

Abstract

The invention discloses a filter pressing circulation system for preparing low-oxygen iron-nickel alloy powder and a preparation method. The system comprises an atomization bin, and a tundish leakage ladle and an atomization spraying disc are arranged at the top of the atomization bin; the bottom of the atomization bin communicates with a filter pressing tank, and the position, close to the bottom, of the filter pressing tank communicates with the interior of the atomization bin through a pipeline; one side of the atomization bin is connected to a sedimentation tank, and a magnetic trapping unit is arranged in the sedimentation tank. The method comprises the steps that iron and nickel are weighed and smelted, and an alloy additive and a slag former are added into a molten solution; heating the solution, cooling, standing, and removing slag; the alloy solution obtained after slag fishing is heated again, and the alloy solution is atomized into iron-nickel alloy catalyst powder through an atomization spraying disc in the argon environment; and finally, the iron-nickel alloy catalyst powder collected in the filter pressing tank and captured by an electromagnet is subjected to roasting reduction in a hydrogen environment, drying and screening, and the low-oxygen iron-nickel alloy powder is obtained. The problem that in the prior art, the oxygen content of the touch coal powder prepared through water atomization is high is solved.

Description

Technical Field

[0001] The invention belongs to the technical field of diamond catalyst powder, and in particular relates to a filter pressing circulation system for preparing low-oxygen iron-nickel alloy powder. The invention also relates to a preparation method of low-oxygen iron-nickel alloy powder. Background Art

[0002] Diamond synthesis by powder catalyst has the advantages of high yield, good quality, and low consumption of raw and auxiliary materials. In recent years, with the research and application of powder catalyst and diamond synthesis process in my country's diamond industry, diamond synthesis by powder catalyst and graphite has shown obvious advantages in many aspects such as quality, output and cemented carbide consumption, and has become an important way of preparation in my country's diamond industry. However, the peroxygen content in the catalyst powder leads to a decrease in the activity of the oxidation catalyst molecules, which has a great adverse effect on the diamond synthesis process. Therefore, the control of the oxygen content of the catalyst powder is an important problem currently faced by the preparation of diamond raw materials, especially the catalyst preparation process.

[0003] The processes for preparing diamond catalyst powder usually include water atomization and gas atomization. The diamond catalyst powder prepared by gas atomization has high sphericity and excellent quality, but low yield and high cost. The diamond catalyst powder prepared by water atomization can not only meet the quality requirements for preparing artificial diamonds, but also has a higher yield and low cost than the gas atomization method, so it is widely used.

[0004] However, the diamond catalyst powder prepared by the traditional water atomization method is limited by the equipment structure and process. In addition to partial loss of raw materials that have not been atomized, the rest needs to be returned to the furnace for smelting, re-atomization and other processes, which increases the production cost. At the same time, the risk of material oxidation in each process link increases, resulting in the oxygen content of the diamond catalyst powder prepared by the traditional water atomization method to be above 8000ppm. The oxygen content of the finished product is relatively high, and it is necessary to add a reduction process in the preparation of the synthetic core column. Summary of the invention

[0005] The purpose of the present invention is to provide a filter pressing circulation system for preparing low-oxygen iron-nickel alloy powder, and to recover the alloy powder through a magnetic capture unit.

[0006] Another object of the present invention is to provide a method for preparing low-oxygen iron-nickel alloy powder, which solves the problem of high oxygen content in coal catalyst powder prepared by water atomization in the prior art.

[0007] The first technical solution adopted by the present invention is a filter pressing circulation system for preparing low-oxygen iron-nickel alloy powder, comprising an atomizing bin, a tundish leakage bag and an atomizing spray plate are arranged on the top of the atomizing bin, and liquid passes through the leakage hole of the tundish leakage bag into the atomizing spray plate for atomization and then falls into the interior of the atomizing bin; The bottom liquid outlet of the atomization bin is connected to a filter press tank through a pipeline, a filter press tank filter bag is arranged at the bottom of the filter press tank, and the filter press tank is also connected to the inside of the atomization bin through a return pipe of the atomization bin near the bottom; one side of the atomization bin is also connected to a pipeline pump through a drainage pipe of the atomization bin, one end of the drainage pipe of the atomization bin extends to the bottom of the inner side of the atomization bin, and the outlet end of the pipeline pump is connected to a sedimentation tank through a pipeline, and a magnetic capture unit is arranged in the sedimentation tank.

[0008] The first technical solution of the present invention is also characterized in that: The atomizing spray disc includes an atomizing spray disc body, a spray disc flow channel for liquid to pass through is arranged in the middle of the atomizing spray disc body, a connecting flange and a sheath pipe are arranged in sequence at the bottom of the atomizing spray disc body, the atomizing spray disc body is connected to the atomizing bin through the connecting flange, and the inner side of the sheath pipe is an atomizing channel; Two groups of nozzles are arranged on the inner side of the atomizing spray disc body. The two groups of nozzles are evenly distributed along the circumference of the atomizing spray disc body. The two groups of nozzles are located below the spray disc flow channel, and the directions of the two groups of nozzles intersect at one point. A spray disc water inlet pipe is arranged on one side of the atomizing spray disc body, and the spray disc water inlet pipe is connected to the two groups of nozzles through pipes respectively.

[0009] The sheath tube is connected with air inlet pipes around it, and argon gas enters the inner side of the atomizing spray disc through the air inlet pipes.

[0010] The axial angle between one group of nozzles and the atomizing spray disc is 42°, the axial angle between the other group of nozzles and the atomizing spray disc is 53°, and the inner diameter of the nozzle is 0.5mm~0.8mm.

[0011] The magnetic collection unit includes a plurality of magnetic collection boxes, which are distributed in a stepped manner. An overflow port is provided on one side of each magnetic collection box, and the liquid in the magnetic collection box flows into the magnetic collection box of the next layer through the overflow port. The water inlet height of the magnetic collection box is lower than the overflow port height. A drainage pipe is also provided at the bottom of each magnetic collection box, and a stop valve is installed on the drainage pipe; hanging rings are also connected to both sides of the magnetic collection box, and an electromagnet for capturing metal powder is installed at the bottom of the magnetic collection box.

[0012] A support frame is fixedly connected to the bottom of each magnetic capture box, and the bottom end of the support frame is fixedly connected to the bottom of the sedimentation tank to support the magnetic capture boxes, thereby forming a stepped arrangement.

[0013] An atomization chamber valve is arranged on the connecting pipe between the atomization chamber and the filter press tank, and the filtration accuracy of the filter bag of the filter press tank is 4μm~6μm.

[0014] The second technical solution adopted by the present invention is a method for preparing low-oxygen iron-nickel alloy powder, comprising: step 1, weighing pure iron and pure nickel, and placing the pure iron and pure nickel into a medium frequency furnace for smelting, and after they are completely melted, sequentially adding alloy additives and slag-forming agents into the solution; Step 2, heating the solution to 1620°C-1650°C, then cooling and letting it stand, and collecting the slag; Step 3, heating the alloy solution after slag removal to 1580° C.-1600° C. again, and atomizing it into an iron-nickel alloy catalyst powder through an atomizing spray plate in an argon environment; Step 4, filter the iron-nickel alloy catalyst powder through a filter press tank, and capture the iron-nickel alloy catalyst powder through a magnetic capture box, and roast and reduce the iron-nickel alloy catalyst powder collected by the filter press and captured by the electromagnet in a hydrogen environment, dry it, and then sieve it to obtain a low-oxygen iron-nickel alloy powder.

[0015] The second technical solution of the present invention is also characterized in that: In step 1, the mass ratio of pure iron to pure nickel is 60-65:35-40; In step 1, the alloy additive is 0.7% to 2% of the total amount of the iron-nickel raw material, and the alloy additive is composed of the following components: the mass fraction of manganese is 30-40%, the mass fraction of chromium is 10-20%, the mass fraction of molybdenum is 40-50%, the mass fraction of carbon is 2-3%, and the mass fraction of silicon is not higher than 0.7%; The slag-forming agent includes dolomite powder and quicklime powder. The mass fraction of dolomite powder in the slag-forming agent is 30-40%, the mass fraction of quicklime powder is 60-70%, and the added amount of the slag-forming agent is 3g-5g per kilogram of iron-nickel raw material.

[0016] The iron-nickel alloy catalyst powder is filtered by a filter press tank, and the iron-nickel alloy catalyst powder is captured by a magnetic capture box. Specifically, the valve of the atomization chamber is closed, and an inert gas is introduced into the filter press tank. The water filtered by the filter bag of the filter press tank is returned to the atomization chamber, and the water returned to the atomization chamber is discharged into the magnetic capture unit through a pipeline pump. The water captured by the magnetic capture box is discharged into the sedimentation tank.

[0017] The beneficial effects of the present invention are: The preparation method of low-oxygen iron-nickel alloy powder of the present invention adopts alloying agent and slag-forming agent, and uses an atomizing spray disc in an inert gas atmosphere to ensure that the particle size distribution of the alloy powder remains unchanged to obtain iron-nickel catalyst powder with higher purity, and then the alloy powder is fully collected by a magnetic capture unit, and is roasted and reduced in a hydrogen atmosphere, which reduces the recycling and powder making links, effectively reduces the risk of material oxidation, and successfully controls the oxygen content of the finished product.

[0018] Some elements (such as manganese, chromium, etc.) in the alloying agent used in the present invention have a strong affinity for oxygen. During the powder making process, these alloying elements will react with oxygen first. For example, manganese reacts with oxygen to form manganese oxide (MnO or Mn2O3), and chromium reacts with oxygen to form oxides such as chromium trioxide (CrO3). Due to these reactions, the oxygen originally dissolved in the metal powder will combine with the alloying elements, thereby reducing the oxygen content in the main body of the metal powder. The slag-forming agent will form slag during the powder making process. The slag can absorb oxide impurities in the molten metal, thereby effectively reducing the oxygen content of the alloy powder to below 3000ppm. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a structural schematic diagram of a filter pressing circulation system for preparing low-oxygen iron-nickel alloy powder according to the present invention; Figure 2 It is a schematic structural diagram of an atomizing spray plate in a filter pressing circulation system for preparing low-oxygen iron-nickel alloy powder according to the present invention; Figure 3 yes Figure 2 Sectional view from perspective A; Figure 4 yes Figure 2 Cross-sectional view from perspective E; Figure 5 It is a schematic flow chart of the method for preparing low-oxygen iron-nickel alloy powder of the present invention.

[0020] In the figure, 1. medium frequency furnace, 2. tundish leakage package, 3. leakage hole, 4. atomizing spray disc, 401. atomizing spray disc body, 402. first nozzle, 403. second nozzle, 404. spray disc water inlet pipe, 405. air inlet pipe, 406. atomizing channel, 407. connecting flange, 408. spray disc flow channel, 409. sheath pipe; 5. Atomization bin, 6. Sedimentation tank, 7. Magnetic capture box, 8. Support frame, 9. Atomization bin valve, 10. Filter press tank, 11. Filter press tank filter bag, 12. Atomization bin return pipe, 13. Atomization bin drain pipe, 14. Pipeline pump, 15. Electromagnet, 16. Lifting ring, 17. Overflow port, 18. Drain pipe. DETAILED DESCRIPTION

[0021] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0022] Example 1 The present invention is used for preparing the filter pressing circulation system of low oxygen iron nickel alloy powder, such as Figure 1 As shown, it includes an atomizing bin 5, a tundish leaking bag 2 and an atomizing spray plate 4 are arranged on the top of the atomizing bin 5, and the liquid passes through the leaking hole 3 of the tundish leaking bag 2 and enters the atomizing spray plate 4 to be atomized and then falls into the atomizing bin 5; Specifically, the molten metal solution is poured into the tundish 2 through the medium frequency furnace 1, and then the metal solution is atomized by the atomizing spray plate 4 to form metal particles that fall into the atomizing bin for the next step of processing.

[0023] The bottom liquid outlet of the atomization bin 5 is connected to a filter press 10 through a pipeline, a filter press filter bag 11 is arranged at the bottom of the filter press 10, and the filter press 10 is also connected to the inside of the atomization bin 5 through an atomization bin return pipe 12 near the bottom; one side of the atomization bin 5 is also connected to a pipeline pump 14 through an atomization bin drain pipe 13, one end of the atomization bin drain pipe 13 extends to the bottom of the inner side of the atomization bin 5, and the outlet end of the pipeline pump 14 is connected to a sedimentation tank 6 through a pipeline, and a magnetic capture unit is arranged in the sedimentation tank 6.

[0024] That is, the filter pressing circulation system of the present invention first performs preliminary filter pressing on the metal powder in the liquid through the filter bag 11 inside the filter pressing tank 10, and the metal powder with smaller particle size returns to the inside of the atomization bin 5 through the atomization bin return pipe 12, and then is sent to the sedimentation tank 6 under the action of the pipeline pump 14, and the metal powder with smaller particle size is adsorbed and captured by the magnetic capture unit inside the sedimentation tank 6.

[0025] Example 2 The present invention discloses a filter pressing circulation system for preparing low-oxygen iron-nickel alloy powder, comprising an atomizing bin 5, a tundish leaking bag 2 and an atomizing spray disc 4 are arranged on the top of the atomizing bin 5, a bottom liquid outlet of the atomizing bin 5 is connected with a filter press tank 10 through a pipeline, a filter press tank filter bag 11 is arranged at the bottom of the filter press tank 10, and the filter press tank 10 is also connected to the inside of the atomizing bin 5 through an atomizing bin water return pipe 12 near the bottom; one side of the atomizing bin 5 is also connected with a pipeline pump 14 through an atomizing bin drain pipe 13, one end of the atomizing bin drain pipe 13 extends to the inner bottom of the atomizing bin 5, and the outlet end of the pipeline pump 14 is connected with a sedimentation tank 6 through a pipeline, and a magnetic capture unit is arranged in the sedimentation tank 6.

[0026] Furthermore, if Figure 2 and Figure 3 As shown, the atomizing spray disc 4 includes an atomizing spray disc body 401, a spray disc flow channel 408 for liquid to pass through is provided in the middle of the atomizing spray disc body 401, a connecting flange 407 and a sheath tube 409 are sequentially provided at the bottom of the atomizing spray disc body 401, the atomizing spray disc body 401 is connected to the atomizing bin 5 through the connecting flange 407, and the inner side of the sheath tube 409 is an atomizing channel 406; Two groups of nozzles are arranged on the inner side of the atomizing spray disc main body 401, and the two groups of nozzles are evenly distributed along the circumference of the atomizing spray disc main body 401. The two groups of nozzles are both located below the spray disc flow channel 408, and the directions of the two groups of nozzles intersect at one point. A spray disc water inlet pipe 404 is arranged on one side of the atomizing spray disc main body 401, and the spray disc water inlet pipe 404 is connected to the two groups of nozzles through pipes respectively.

[0027] In this embodiment, a group of nozzles uses six nozzles, such as Figure 4 As shown, the axial angle between the six first nozzles 402 and the atomizing spray disc 4 is 42°, the axial angle between the six second nozzles 403 and the atomizing spray disc 4 is 53°, and the spray directions of the twelve nozzles intersect at one point, which is located as far as possible on the central axis of the spray disc flow channel 408. They play the role of main atomization and atomization of missed molten steel and reducing the influence of nitrogen gas flow.

[0028] The first nozzle 402 and the second nozzle 403 are both connected to the spray plate water inlet pipe 404 for spraying high-pressure water. The first nozzle 402 and the second nozzle 403 are cylindrical nozzles with an inner diameter of 0.5 mm to 0.8 mm and an atomized water flow rate of 120-200 L / min. The purpose is to effectively avoid powder recoil, meet the powder production needs of specific particle size and morphology, and improve the powder formation rate.

[0029] Furthermore, the jacket tube 409 is connected with an air inlet pipe 405 around it, and argon enters the inner side of the atomizing spray disc 4 through the air inlet pipe 405. Argon is introduced into the air inlet pipe 405, and during the powder making process, argon will not react with the metal, and can effectively prevent the metal powder from being oxidized during the preparation process.

[0030] Example 3 The present invention discloses a filter pressing circulation system for preparing low-oxygen iron-nickel alloy powder, comprising an atomizing bin 5, a tundish leaking bag 2 and an atomizing spray plate 4 are arranged on the top of the atomizing bin 5, a bottom liquid outlet of the atomizing bin 5 is connected with a filter press tank 10 through a pipeline, an atomizing bin valve 9 is arranged on the connecting pipeline between the atomizing bin 5 and the filter press tank 10; a filter press tank filter bag 11 is arranged at the bottom of the filter press tank 10, and the filtration accuracy of the filter press tank filter bag is 4μm-6μm.

[0031] The filter press tank 10 is also connected to the inside of the atomization bin 5 through the atomization bin return pipe 12 near the bottom; one side of the atomization bin 5 is also connected to a pipeline pump 14 through an atomization bin drain pipe 13, one end of the atomization bin drain pipe 13 extends to the bottom of the inner side of the atomization bin 5, and the outlet end of the pipeline pump 14 is connected to the sedimentation tank 6 through a pipeline, and a magnetic capture unit is arranged in the sedimentation tank 6.

[0032] Furthermore, the magnetic capture unit of the present invention includes a plurality of magnetic capture boxes 7, which are distributed in a stepped manner, and an overflow port 17 is provided on one side of each magnetic capture box 7. The liquid in the magnetic capture box 7 flows into the magnetic capture box 7 of the next layer through the overflow port 17. The water inlet height of the magnetic capture box 7 is lower than the overflow port 17. The overflow port 17 should be located in the middle of the magnetic capture box 7 to facilitate the discharge of water after one capture into the next magnetic capture box 7.

[0033] A drain pipe 18 is also provided at the bottom of each magnetic collection box 7, and a stop valve is installed on the drain pipe 18; hanging rings 16 are also connected to both sides of the magnetic collection box 7, and the hanging rings 16 are evenly distributed around the box body, and usually 2 to 4 hanging rings are provided to facilitate the lifting of the magnetic collection box 7. An electromagnet 15 for capturing metal powder is installed at the bottom of the magnetic collection box 7.

[0034] This embodiment uses three magnetic collection boxes 7 , and the sum of the volumes of the three magnetic collection boxes 7 is greater than half of the volume of water discharged from the atomization chamber 5 .

[0035] Furthermore, a support frame 8 is fixedly connected to the bottom of each magnetic capture box 7, and the bottom end of the support frame 8 is fixedly connected to the bottom of the sedimentation tank 6 for supporting the magnetic capture box 7, thereby forming a stepped arrangement.

[0036] Example 4 The method for preparing low-oxygen iron-nickel alloy powder of the present invention adopts the filter pressing circulation system for preparing low-oxygen iron-nickel alloy powder, such as Figure 5 As shown, the specific steps include: Step 1, weighing pure iron and pure nickel, and putting the pure iron and pure nickel into a medium frequency furnace 1 for smelting, and after they are completely melted, adding alloy additives and slag-forming agents into the solution in sequence; Step 2, heating the solution to 1620°C-1650°C, then cooling and letting it stand, and collecting the slag; Step 3, heating the alloy solution after slag removal to 1580° C.-1600° C. again, and atomizing it into an iron-nickel alloy catalyst powder through an atomizing spray plate in an argon environment; Step 4, filter the iron-nickel alloy catalyst powder through the filter press 10, and capture the iron-nickel alloy catalyst powder through the magnetic capture box 7, and roast and reduce the iron-nickel alloy catalyst powder collected by the filter press and captured by the electromagnet 15 in a hydrogen environment, dry it, and then sieve it to obtain low-oxygen iron-nickel alloy powder.

[0037] Some elements in alloy additives (such as manganese, chromium, etc.) have a strong affinity for oxygen. During the powder making process, these alloy elements will react with oxygen first. For example, manganese reacts with oxygen to form manganese oxide (MnO or Mn2O3), and chromium reacts with oxygen to form oxides such as chromium trioxide (CrO3). Due to these reactions, the oxygen originally dissolved in the metal powder will combine with the alloy elements, thereby reducing the oxygen content in the main body of the metal powder. Some of these generated oxides will be removed in subsequent processes (such as refining, etc.).

[0038] Slag-forming agents will form slag during the powder making process. Slag can absorb oxide impurities in the molten metal. In liquid metal, oxygen often exists in the form of various metal oxides. When the slag formed by the slag-forming agent comes into contact with the molten metal, the oxides in the molten metal (such as FeO, etc.) will enter the slag phase due to the adsorption effect of the interface. This is because the slag provides a place for oxides to gather, and there is a certain chemical potential difference between the slag and the molten metal, which promotes the migration of oxides from the molten metal to the slag, thereby achieving the purpose of reducing the oxygen content in the metal powder.

[0039] Example 5 The method for preparing low-oxygen iron-nickel alloy powder of the present invention adopts the above-mentioned filter pressing circulation system for preparing low-oxygen iron-nickel alloy powder, and specifically comprises the following steps: Step 1, weighing pure iron and pure nickel, the mass ratio of pure iron to pure nickel is 60-65:35-40; and putting the pure iron and pure nickel into a medium frequency furnace 1 for smelting, and after they are completely melted, adding an alloy additive and a slag-forming agent to the solution in sequence; Furthermore, the alloy additive added is 0.7% to 2% of the total amount of the iron-nickel raw material, and the alloy additive is composed of the following components: the mass fraction of manganese is 30-40%, the mass fraction of chromium is 10-20%, the mass fraction of molybdenum is 40-50%, the mass fraction of carbon is 2-3%, and the mass fraction of silicon is not higher than 0.7%; The slag-forming agent includes dolomite powder and quicklime powder. The mass fraction of dolomite powder in the slag-forming agent is 30-40%, the mass fraction of quicklime powder is 60-70%, and the added amount of the slag-forming agent is 3g-5g per kilogram of iron-nickel raw material.

[0040] Step 2, heating the solution to 1620°C-1650°C, then cooling and letting it stand, and collecting the slag; Step 3, heating the alloy solution after slag removal to 1580° C.-1600° C. again, and atomizing it into an iron-nickel alloy catalyst powder through an atomizing spray plate in an argon environment; Step 4, filter the iron-nickel alloy catalyst powder through the filter press 10, and capture the iron-nickel alloy catalyst powder through the magnetic capture box 7, specifically, close the atomization chamber valve 9, pass inert gas into the filter press 10, return the water filtered by the filter bag 11 of the filter press to the atomization chamber 5, and discharge the water returned to the atomization chamber 5 into the magnetic capture unit through the pipeline pump 14, and discharge the water captured by the magnetic capture box 7 into the sedimentation tank 6. After the water in the sedimentation tank 6 is settled for 24 hours, it can be recycled after two-stage filtration.

[0041] The iron-nickel alloy catalyst powder collected by filter pressing and captured by the electromagnet 15 is calcined, reduced, and dried in a hydrogen environment, and then sieved to obtain low-oxygen iron-nickel alloy powder.

[0042] The preparation method of low-oxygen iron-nickel alloy powder of the present invention adopts alloying agent and slag-forming agent, and uses an atomizing spray disc in an inert gas atmosphere to ensure that the particle size distribution of the alloy powder remains unchanged to obtain iron-nickel catalyst powder with higher purity, and then the alloy powder is fully collected by a magnetic capture unit, and is roasted and reduced in a hydrogen atmosphere, which reduces the recycling and powder making links, effectively reduces the risk of material oxidation, and successfully controls the oxygen content of the finished product.

[0043] Example 6 On the basis of Example 5, the step 3 of the present invention is to atomize the iron-nickel alloy catalyst powder in an argon environment through an atomizing spray plate. Specifically, after the molten steel is melted in the medium frequency furnace 1 and reaches a specified temperature, the molten steel is poured into the tundish 2. The molten steel passes through the leakage hole 3 in the tundish 2 and flows through the spray plate flow channel 408. The high-pressure underwater metal flow liquid sprayed by the first nozzle 402 and the second nozzle 403 of the atomizing spray plate is impacted and broken into fine droplets, and flows down through the atomizing channel 406 to achieve full atomization of the metal. At the same time, the argon gas sprayed from the air inlet pipe 405 creates an argon atmosphere in the sheath pipe 409, so that the entire atomization process is carried out under argon protection.

[0044] Furthermore, the calcination reduction in step 4 is specifically to raise the temperature to 200° C. in a high-purity hydrogen atmosphere of 0.1 MPa, maintain the temperature for 1 to 1.5 hours, then stop heating and cool the temperature to room temperature.

[0045] Furthermore, the mesh size of the screening in step 4 is 200 mesh to 350 mesh.

[0046] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0047] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A filter press circulation system for preparing low-oxygen iron-nickel alloy powder, characterized in that: It comprises an atomizing bin (5), wherein a tundish leakage bag (2) and an atomizing spray disc (4) are arranged on the top of the atomizing bin (5), and liquid passes through the leakage hole (3) of the tundish leakage bag (2) and enters the atomizing spray disc (4) to be atomized and then falls into the interior of the atomizing bin (5); The bottom liquid outlet of the atomization bin (5) is connected to a filter press (10) via a pipeline, a filter press filter bag (11) is arranged at the bottom of the filter press (10), and the filter press (10) is also connected to the inside of the atomization bin (5) via an atomization bin return pipe (12) near the bottom; one side of the atomization bin (5) is also connected to a pipeline pump (14) via an atomization bin drainage pipe (13), one end of the atomization bin drainage pipe (13) extends to the bottom of the inner side of the atomization bin (5), and the outlet end of the pipeline pump (14) is connected to a sedimentation tank (6) via a pipeline, and a magnetic capture unit is arranged in the sedimentation tank (6).

2. The filter press circulation system for preparing low-oxygen iron-nickel alloy powder according to claim 1, characterized in that: The atomizing spray disc (4) comprises an atomizing spray disc body (401), a spray disc flow channel (408) for liquid to pass through is provided in the middle of the atomizing spray disc body (401), a connecting flange (407) and a sheath tube (409) are provided in sequence at the bottom of the atomizing spray disc body (401), the atomizing spray disc body (401) is connected to the atomizing bin (5) via the connecting flange (407), and the inner side of the sheath tube (409) is an atomizing channel (406); Two groups of nozzles are arranged inside the atomizing spray disc body (401), and the two groups of nozzles are evenly distributed along the circumference of the atomizing spray disc body (401). The two groups of nozzles are both located below the spray disc flow channel (408), and the directions of the two groups of nozzles intersect at one point. A spray disc water inlet pipe (404) is arranged on one side of the atomizing spray disc body (401), and the spray disc water inlet pipe (404) is connected to the two groups of nozzles through pipes respectively.

3. The filter press circulation system for preparing low-oxygen iron-nickel alloy powder according to claim 2, characterized in that: The jacket tube (409) is connected to an air inlet pipe (405) on all sides, and argon gas enters the inner side of the atomizing spray disc (4) through the air inlet pipe (405).

4. The filter press circulation system for preparing low-oxygen iron-nickel alloy powder according to claim 2, characterized in that: The axial angle between the nozzles of one group and the atomizing spray disc (4) is 42°, the axial angle between the nozzles of another group and the atomizing spray disc (4) is 53°, and the inner diameter of the nozzles is 0.5 mm to 0.8 mm.

5. The filter press circulation system for preparing low-oxygen iron-nickel alloy powder according to claim 1, characterized in that: The magnetic capture unit comprises a plurality of magnetic capture boxes (7), the plurality of magnetic capture boxes (7) being distributed in a stepped manner, an overflow port (17) being provided on one side of each magnetic capture box (7), the liquid in the magnetic capture box (7) flowing into the magnetic capture box (7) of the next layer through the overflow port (17), and the water inlet of the magnetic capture box (7) having a height lower than the overflow port (17); A drainage pipe (18) is also provided at the bottom of each magnetic collection box (7), and a stop valve is installed on the drainage pipe (18); hanging rings (16) are also connected to both sides of the magnetic collection box (7), and an electromagnet (15) for capturing metal powder is installed at the bottom of the magnetic collection box (7).

6. The filter press circulation system for preparing low-oxygen iron-nickel alloy powder according to claim 5, characterized in that: A support frame (8) is fixedly connected to the bottom of each magnetic capture box (7), and the bottom end of the support frame (8) is fixedly connected to the bottom of the sedimentation tank (6) for supporting the magnetic capture boxes (7), thereby forming a stepped arrangement.

7. The filter press circulation system for preparing low-oxygen iron-nickel alloy powder according to claim 1, characterized in that: An atomization bin valve (9) is provided on the communication pipeline between the atomization bin (5) and the filter press tank (10), and the filtration accuracy of the filter bag of the filter press tank is 4 μm to 6 μm.

8. A method for preparing low-oxygen iron-nickel alloy powder, characterized in that: The filter press circulation system for preparing low-oxygen iron-nickel alloy powder according to any one of claims 1 to 7 comprises the following steps: Step 1, weighing pure iron and pure nickel, and placing the pure iron and pure nickel into a medium frequency furnace (1) for smelting, and after they are completely melted, adding alloy additives and slag-forming agents into the solution in sequence; Step 2, heating the solution to 1620°C-1650°C, then cooling and letting it stand, and collecting the slag; Step 3, heating the alloy solution after slag removal to 1580° C.-1600° C. again, and atomizing it into an iron-nickel alloy catalyst powder through an atomizing spray plate in an argon environment; Step 4, filtering the iron-nickel alloy catalyst powder through a filter press tank (10), and capturing the iron-nickel alloy catalyst powder through a magnetic capture box (7), and calcining, reducing, and drying the iron-nickel alloy catalyst powder obtained by filtering and capturing by an electromagnet (15) in a hydrogen environment, and then sieving to obtain a low-oxygen iron-nickel alloy powder.

9. The method for preparing low-oxygen iron-nickel alloy powder according to claim 8, characterized in that: In the step 1, the mass ratio of pure iron to pure nickel is 60-65:35-40; In step 1, the alloy additive is 0.7% to 2% of the total amount of the iron-nickel raw material, and the alloy additive is composed of the following components: the mass fraction of manganese is 30-40%, the mass fraction of chromium is 10-20%, the mass fraction of molybdenum is 40-50%, the mass fraction of carbon is 2-3%, and the mass fraction of silicon is not higher than 0.7%; The slag-forming agent comprises dolomite powder and quicklime powder, the mass fraction of dolomite powder in the slag-forming agent is 30-40%, the mass fraction of quicklime powder is 60-70%, and the added amount of the slag-forming agent is 3g-5g per kilogram of iron-nickel raw material.

10. The method for preparing low-oxygen iron-nickel alloy powder according to claim 8, characterized in that: The iron-nickel alloy catalyst powder is filtered by the filter press tank (10) and the iron-nickel alloy catalyst powder is captured by the magnetic capture box (7). Specifically, the valve (9) of the atomization chamber is closed, an inert gas is introduced into the filter press tank (10), water filtered by the filter bag (11) of the filter press tank is pumped back into the atomization chamber (5), and the water pumped back into the atomization chamber (5) is discharged into the magnetic capture unit through the pipeline pump (14), and the water captured by the magnetic capture box (7) is discharged into the sedimentation tank (6).

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