Vaporized powder combustion device, nano high-purity spherical oxide powder and preparation method of nano high-purity spherical oxide powder

Abstract

The invention discloses a vaporized powder combustion device, nano high-purity spherical oxide powder and a preparation method of the nano high-purity spherical oxide powder. A combustion gun of the vaporized powder combustion device is sequentially provided with a raw material carrier gas channel, an annular fuel gas channel and an annular combustion-supporting gas channel at intervals from inside to outside, and an ignition device is arranged on the portion, located on the outer side of a combustion gun insertion part, of a vaporized combustion chamber; an oxygen inlet channel is formed between the outer wall of the combustion gun and the inner wall of the combustion gun insertion part, at least two oxygen inlets which are uniformly distributed at intervals are formed in the side wall, located on the outer side of the combustion gun insertion part, of the vaporization combustion chamber, and the included angle between the gas inlet direction of the oxygen inlets and the central axis of the flame jetting direction of the combustion gun is 20-70 degrees. The device can flexibly adjust the temperature, the width and the length of flames generated by the combustion gun, can ensure that powder raw materials are completely vaporized before leaving a flame area, can flexibly adjust the concentration and the total flow of oxygen on the periphery of the flames, and can achieve sufficient vaporization combustion of the powder raw materials.

Description

Technical Field

[0001] The present invention relates to the technical field of powder spheroidization, in particular to a vaporized powder combustion device, nanometer high-purity spherical oxide powder and a preparation method thereof. Background Art

[0002] Amid the rapid development of high-tech industries such as new energy, electronics, aerospace, and biomedicine, the demand for high-performance materials is exploding. Nano-sized, high-purity spherical oxide powders, due to their unique physical and chemical properties, such as high specific surface area, high activity, and uniform morphology, are widely used in the preparation of high-end functional materials such as ceramics, coatings, catalysts, and semiconductors. As one of the key processes for preparing these powders, the vaporized powder combustion method has long held the core technology and key equipment in foreign hands, subject to strict technical protection.

[0003] While the publicly available, independently developed vaporized powder combustion device has achieved basic functionality, it suffers from a technical flaw in the actual production process, resulting in insufficient combustion, which results in a large amount of unreacted raw material remaining in the final product. This phenomenon not only reduces the purity and sphericity of the powder, but also directly affects the performance of downstream functional materials.

[0004] In view of this, the present invention is proposed. Summary of the Invention

[0005] The purpose of the present invention is to provide a vaporized powder combustion device, nanometer high-purity spherical oxide powder and a preparation method thereof, so as to improve the above-mentioned technical problems.

[0006] The present invention is achieved in that: In a first aspect, the present invention provides a vaporization powder combustion device, which includes a vaporization combustion chamber and a combustion gun, the vaporization combustion chamber is provided with a combustion gun insertion portion, one end portion of the combustion gun is inserted into the combustion gun insertion portion and communicates with the interior of the vaporization combustion chamber, the combustion gun is sequentially provided with a raw material carrier gas channel, an annular fuel gas channel, and an annular fuel-supporting gas channel from the inside to the outside, the raw material carrier gas channel is provided with a first nozzle at one end located in the vaporization combustion chamber, the annular fuel gas channel is provided with a second nozzle at one end located in the vaporization combustion chamber, the second nozzle is sleeved outside the first nozzle, and a gap is provided between the first nozzle and the second nozzle, and an ignition device for igniting the fuel gas ejected from the second nozzle is provided on the side wall of the vaporization combustion chamber located outside the combustion gun insertion portion; An annular raw material oxidation reaction oxygen inlet channel is provided between the outer wall of the burner gun and the inner wall of the burner gun insertion portion, and a first raw material oxidation reaction oxygen inlet port connected to the annular raw material oxidation reaction oxygen inlet channel is provided on the burner gun insertion portion. The side wall of the vaporization combustion chamber located on the outside of the burner gun insertion portion is provided with at least two second raw material oxidation reaction oxygen inlets evenly spaced, and the angle between the gas introduction direction of the second raw material oxidation reaction oxygen inlet and the central axis of the flame injection direction of the burner gun is 20 to 70 degrees.

[0007] In some preferred embodiments, the burner gun insertion portion is hollow tubular, and the vaporization combustion chamber is further provided with a conical connecting section, the conical connecting section having a narrowed end connected to the burner gun insertion portion, the ignition device and the second raw material oxidation reaction oxygen inlet are both provided in the conical connecting section, and the ignition device is provided in the area between the second raw material oxidation inlet and the burner gun insertion portion.

[0008] In some preferred embodiments, the burner insertion portion is located at the top of the vaporization combustion chamber, and the number of the second raw material oxidation reaction oxygen inlet is at least three, and they are located at the same horizontal height and have the same jet angle.

[0009] In some preferred embodiments, a first annular protrusion for changing the direction of airflow is provided on the outer wall of the first nozzle, and a second annular protrusion for changing the direction of airflow is also provided on the outer wall of the second nozzle.

[0010] In some preferred embodiments, the combustion gun includes a raw material inlet pipe, a fuel gas inlet pipe, and a fuel gas inlet pipe that are coaxially connected from the inside to the outside.

[0011] In some preferred embodiments, the first nozzle extends from the second nozzle, and the first nozzle is telescopically connected to the raw material inlet pipe, and the second nozzle is telescopically connected to the gas inlet pipe.

[0012] In some preferred embodiments, the combustion gun is further provided with an annular backup gas channel spaced apart from the annular combustion-supporting gas channel.

[0013] In some preferred embodiments, the part of the combustion gun located at the combustion gun insertion part is also provided with a cooling channel, the cooling medium inlet and the cooling medium outlet are both located at the upper part of the cooling channel, and are located outside the combustion gun insertion part when installed, and a cooling medium inlet pipe is also provided at the cooling medium inlet, and the cooling medium inlet pipe enters the cooling channel and extends downward to the bottom of the cooling channel.

[0014] In a second aspect, the present invention further provides a method for preparing nano-high-purity spherical oxide powder, which comprises: preparing nano-high-purity spherical oxide powder by using the above-mentioned vaporization powder combustion device.

[0015] In some preferred embodiments, the method for preparing nano high-purity spherical oxide powder comprises the following steps: Ignite the combustion gun by the ignition device; Control the gas flow rate to 45-60 L / min and the flow rate of the supporting gas to maintain the oxygen excess coefficient at 0-10%; The oxidation reaction gas is introduced through the first raw material oxidation reaction oxygen inlet and the second raw material oxidation reaction oxygen inlet at a total flow rate of 600 L / min to 800 L / min, and the ratio of the oxidation reaction gas introduced into the first raw material oxidation reaction oxygen inlet to the second raw material oxidation reaction oxygen inlet is (30-40): (60-70); Feed raw material powder, control the powder injection rate to 30~40kg / h, and the gas-solid ratio to 3.0~4.0.

[0016] In a third aspect, the present invention further provides a nano-high-purity spherical oxide powder prepared by the above method, wherein the nano-high-purity spherical oxide powder satisfies the following characteristics: (1) The nano high-purity spherical oxide powder does not contain raw materials that have not been vaporized and combusted; (2) The nano high-purity spherical oxide powder does not contain nitrate ions; (3) The sphericity of the nano high-purity spherical oxide powder is greater than 99%.

[0017] The present invention has the following beneficial effects: the specific structure of the combustion gun and the structural design of the first raw material oxidation reaction oxygen inlet and the second raw material oxidation reaction oxygen inlet enable the gas gun to produce a stable flame zone, namely, the internal flame temperature exceeds the raw material vaporization temperature, the flame width completely surrounds the powder diffusion zone, the flame length is sufficient for complete powder vaporization, the internal flame is low in combustion-supporting gas, and the peripheral flame is rich in raw material oxidation reaction oxygen. Specifically, the raw material carrier gas channel, the annular fuel gas channel, and the annular combustion-supporting gas channel are arranged in the same direction, with the raw material carrier gas channel located in the center. This ensures that after the fuel gas ejected from the combustion gun is ignited, the internal flame is low in combustion-supporting gas, and the raw material powder is directly vaporized without burning before leaving the flame zone. Furthermore, the raw material oxidation reaction oxygen introduced through the first raw material oxidation reaction oxygen inlet at the top and the second raw material oxidation reaction oxygen inlet at the side surrounds the flame zone, allowing the raw material powder to fully contact the raw material oxidation reaction oxygen (oxygen) outside the flame, instantly completing vaporization and combustion, thereby achieving complete vaporization and combustion of the powdered raw material. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0019] Figure 1 This is a schematic diagram of the overall structure of the vaporized powder combustion device according to the first embodiment of the present invention; Figure 2 This is a schematic structural diagram of a combustion gun of a vaporized powder combustion device according to a first embodiment of the present invention; Figure 3 is an XRD pattern of the product of Group 1 of the second embodiment of the present invention; Figure 4 FIG. 4 is an XRD spectrum of the product of Group 2 according to the second embodiment of the present invention.

[0020] Illustration: 10-vaporized powder combustion device; 100-vaporized combustion chamber; 101-oxygen inlet for the first raw material oxidation reaction; 102-oxygen inlet for the second raw material oxidation reaction; 110-burner gun insertion portion; 120-conical connecting section; 200-burner gun; 201-raw material carrier gas channel; 202-annular fuel gas channel; 203-annular combustion-supporting gas channel; 204-annular standby gas channel; 205-cooling channel; 210-first nozzle; 211-first annular protrusion; 220-second nozzle; 221-second annular protrusion; 230-raw material inlet pipe; 231-raw material carrier gas inlet; 240-fuel gas inlet pipe; 241-fuel gas inlet; 250-combustion-supporting gas inlet pipe; 251-combustion-supporting gas inlet; 260-standby gas inlet pipe; 261-standby gas inlet; 270-cooling medium inlet pipe; 271-cooling medium inlet; 272-cooling medium outlet; 300-ignition device. DETAILED DESCRIPTION

[0021] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations.

[0022] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention as claimed, but rather merely represents selected embodiments of the present invention. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without creative effort are intended to fall within the scope of protection of the present invention.

[0023] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings.

[0024] In the description of the present invention, it should be noted that if the terms "upper", "lower", "inside", "outside", etc. appear, the orientation or position relationship indicated is based on the orientation or position relationship shown in the accompanying drawings, or is the orientation or position relationship in which the product of the invention is usually placed when in use. It is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be understood as a limitation on the present invention.

[0025] In addition, the terms "first," "second," and "third" are used solely for descriptive purposes and are not to be construed as indicating or implying relative importance. In the examples, where specific conditions are not specified, the experiments were performed under conventional conditions or those recommended by the manufacturer. Reagents and instruments used, for which the manufacturer is not specified, are commercially available conventional products.

[0026] It should be noted that, in the absence of conflict, the features in the embodiments of the present invention may be combined with each other.

[0027] The overall structure, working principle and technical effects of a vaporized powder combustion device, nanometer high-purity spherical oxide powder and preparation method thereof provided by the present invention are described in detail below through examples and in conjunction with the accompanying drawings.

[0028] First embodiment See also Figure 1 An embodiment of the present invention provides a vaporization powder combustion device 10, which includes a vaporization combustion chamber 100 and a combustion gun 200. The vaporization combustion chamber 100 is provided with a combustion gun insertion portion 110, and one end portion of the combustion gun 200 is inserted into the combustion gun insertion portion 110 and communicated with the interior of the vaporization combustion chamber 100.

[0029] The vaporization combustion chamber 100 is a key place for raw material reaction and gas phase generation. It is a closed container as a whole and is made of internal high-temperature materials (such as quartz, corundum or zirconium-containing refractory bricks). In this embodiment, the overall shape of the vaporization combustion chamber 100 is cylindrical. Of course, its shape can also be adjusted in other embodiments.

[0030] The burner insert 110 is positioned at the center of the top of the vaporizer combustion chamber 100. The burner insert is a hollow tubular structure, through which the burner 200 can be removably connected to the vaporizer combustion chamber 100. One end of the burner 200 is inserted into the burner insert 110 and extends to the bottom of the burner insert 110, which is close to the vaporizer combustion cavity inside the vaporizer combustion chamber 100. It should be noted that only a portion of the burner 200 is inserted into the burner insert 110. During installation, a sealing structure is provided between the inner wall of the top of the burner insert 110 and the outer wall of the burner 200 to achieve a sealed design for the top of the vaporizer combustion chamber 100.

[0031] The vaporization combustion chamber 100 is also equipped with a conical connecting section 120, the conical end of which is connected to the burner insert 110. The provision of the conical connecting section 120 creates a "convergence effect" for the gas before entering the reaction zone. The gas flow rate gradually increases from the bottom of the cone (larger cross-sectional area) to the top (smaller cross-sectional area), forming turbulent or swirling flow, promoting molecular mixing of different gases and reducing local over-concentration or over-leanness, thereby enhancing gas mixing efficiency and improving reaction uniformity. In addition, the inclination angle of the conical connecting section 120 (typically designed to be 30°-60°) reduces direct collisions between the gas and the wall, and the high temperature of the conical inner wall is easily maintained (heat concentration), reducing the condensation and adhesion of vaporized products on the wall.

[0032] See also Figure 2 In this embodiment, the combustion gun 200 is sequentially arranged from the inside to the outside with a raw material carrier gas channel 201, an annular gas channel 202, and an annular combustion-supporting gas channel 203. A first nozzle 210 is provided at one end of the raw material carrier gas channel 201 located within the vaporization combustion chamber 100, and a second nozzle 220 is provided at one end of the annular gas channel 202 located within the vaporization combustion chamber 100. The second nozzle 220 is sleeved outside the first nozzle 210, and a gap is provided between the first nozzle 210 and the second nozzle 220. This structural arrangement ensures that the direction of raw material ejection is consistent with the direction of the flame. Furthermore, by regulating the amount of combustion-supporting gas introduced into the annular combustion-supporting gas channel 203, a low amount of combustion-supporting gas can be achieved within the flame, so that the powdered raw material will hardly burn before leaving the flame area and will directly vaporize.

[0033] Specifically, in this embodiment, the combustion gun 200 includes, from the inside out, a coaxially arranged raw material inlet pipe 230, a fuel gas inlet pipe 240, and a oxidant gas inlet pipe 250. The raw material inlet pipe 230 is a hollow tube, the central passage of which serves as the raw material carrier gas passage 201. Carrier gas and raw material are introduced through the raw material carrier gas inlet 231 at its end. Under the influence of the carrier gas, the raw material is sprayed into the vaporization combustion chamber 100 through the first nozzle 210.

[0034] The gas inlet pipe 240 is also a hollow tube. Its inner wall and the outer wall of the raw material inlet pipe 230 form an annular gas channel 202. Gas enters the annular gas channel 202 through a gas inlet 241 located at the top of the gas inlet pipe 240 and is then ejected through a second nozzle 220 connected to the bottom of the gas inlet pipe 240. Flange structures are provided at the top of the raw material inlet pipe 230 and the top of the gas inlet pipe 240 for connection. These flanges are welded to the outer wall of the pipe. It should be noted that a sealing structure is provided at the flange connection between the two to ensure a tight seal at the top of the annular gas channel 202.

[0035] Furthermore, the first nozzle 210 extends from the second nozzle 220 and is telescopically connected to the raw material inlet pipe 230. The second row of nozzles is telescopically connected to the gas inlet pipe 240. Gas is ejected from the annular gap formed between the inner wall of the second nozzle 220 and the outer wall of the first nozzle 210. By controlling the relative position of the first nozzle 210 and the second nozzle 220, the gas flow direction can be effectively controlled, thereby achieving the purpose of adjusting the flame shape.

[0036] Furthermore, a first annular protrusion 211 for changing the direction of airflow is provided on the outer wall of the first nozzle 210, and a second annular protrusion 221 for changing the direction of airflow is also provided on the outer wall of the second nozzle 220. Specifically, the first annular protrusion 211 and the second annular protrusion 221 are both high in the middle and low on both sides, which can change the direction of airflow to achieve the purpose of adjusting the flame shape.

[0037] The combustion-supporting gas inlet pipe 250 is also a hollow tube. Its inner wall and the outer wall of the gas inlet pipe 240 form an annular combustion-supporting gas channel 203. A combustion-supporting gas inlet 251 is provided at the top of the combustion-supporting gas inlet pipe 250. The bottom of the combustion-supporting gas inlet pipe 250 extends above the second nozzle 220. Combustion-supporting gas entering through the combustion-supporting gas inlet 251 flows out of the second nozzle 220 through the annular combustion-supporting gas channel 203. The top of the combustion-supporting gas inlet pipe 250 and the upper middle portion of the gas inlet pipe 240 are also provided with flange structures for mating connection. Similarly, the connection between the flange structures is also provided with a sealing structure to ensure the sealing of the top of the annular combustion-supporting gas channel 202. It should be noted that the combustion-supporting gas in this embodiment generally refers to oxygen.

[0038] The above structure allows the sprayed raw materials, fuel gas and supporting gas to be mixed and sprayed at the outlet end of the combustion gun 200, and a specific powder spray shape and a specific flame shape can be achieved by regulating the flow and direction of the three gases.

[0039] In this embodiment, the combustion gun 200 is further provided with an annular backup gas channel 204 spaced apart from the annular supporting gas channel 203. That is, a backup gas inlet pipe 260 is further provided outside the supporting gas inlet pipe 250. The inner wall of the backup gas inlet pipe 260 and the outer wall of the supporting gas inlet pipe 250 form the annular backup gas channel 204. The upper portion of the backup gas inlet pipe 260 is provided with a backup gas inlet 261 connected to the annular backup gas channel 204. The backup gas can be an inert gas. By introducing the backup gas, the oxygen concentration can be adjusted, ultimately achieving the purpose of controlling the oxidation reaction rate of the vaporized raw material. The upper portion of the supporting gas inlet pipe 250 and the top of the backup gas inlet pipe 260 are also respectively provided with flange structures for mating connection. Similarly, the connection of the flange structures is also provided with a sealing structure to ensure the sealing of the top of the annular backup gas channel 204.

[0040] Furthermore, in this embodiment, the portion of the burner 200 located at the insertion portion of the burner 200 is further provided with a cooling channel 205. The cooling channel 205 is formed by the space between the inner wall of the pipe sleeved on the backup air inlet pipe 260 and the outer wall of the backup air inlet pipe 260. The upper and lower ends of the cooling channel 205 are closed. The cooling medium inlet 271 and the cooling medium outlet 272 are both located at the upper portion of the cooling channel 205 and, when installed, are located outside the insertion portion of the burner 200. A cooling medium inlet pipe 270 is also provided at the cooling medium inlet 271. The cooling medium inlet pipe 270 enters the cooling channel 205 and extends downward to the bottom of the cooling channel 205, thereby achieving the purpose of cooling medium in the cooling channel 205 entering from the bottom and exiting from the top, thereby improving cooling efficiency. It should be noted that the cooling medium includes, but is not limited to, water.

[0041] It should be noted that in this embodiment, the raw material inlet pipe 230, the fuel gas inlet pipe 240, the oxidant gas inlet pipe 250, and the backup gas inlet pipe 260 are all coaxially arranged to ensure uniform discharge of the various gases from the pipe outlets. Furthermore, the raw material carrier gas inlet 231, the fuel gas inlet 241, the oxidant gas inlet 251, and the backup gas inlet 261 are each equipped with a control device, such as a control valve, for controlling the flow rate of the raw material and various gases. Furthermore, in some embodiments, the backup gas inlet pipe 260 and the cooling channel 205 may be optionally provided as needed.

[0042] See again Figure 1 An ignition device 300 is installed on the sidewall of the vaporization combustion chamber 100, located outside the burner insertion portion 110, for igniting the gas ejected from the second nozzle 220. This ignition device 300 is a conventional structure in the art and will not be described in detail here. The ignition device 300 is located within the conical connecting section 120 and enables flame generation.

[0043] An annular raw material oxidation reaction oxygen inlet channel is defined between the outer wall of the burner 200 and the inner wall of the burner insert 110. The burner insert 110 is provided with a first raw material oxidation reaction oxygen inlet port 101 communicating with the annular raw material oxidation reaction oxygen inlet channel. The sidewall of the vaporization combustion chamber 100 located outside the burner insert 110 is provided with at least two evenly spaced second raw material oxidation reaction oxygen inlets 102. The gas inlet direction of the second raw material oxidation reaction oxygen inlets 102 is oriented at an angle of 20 to 70 degrees with the central axis of the flame ejection direction of the burner 200. The first raw material oxidation reaction oxygen inlet 101 and the second raw material oxidation reaction oxygen inlet 102 are respectively provided with a first oxygenation device and a second oxygenation device, and are also provided with a control device for controlling the flow rate.

[0044] Spraying the raw material oxidation reaction oxygen through the top and side is beneficial to covering the flame area, so that the vaporized raw material leaving the flame area can fully contact with the raw material oxidation reaction oxygen and complete vaporization and combustion instantly.

[0045] Furthermore, in this embodiment, the number of second raw material oxidation reaction oxygen inlets 102 can be illustratively three, and they are located at the same horizontal height and have the same jet angle. In other embodiments, more second raw material oxidation reaction oxygen inlets 102 can also be provided. The multiple second raw material oxidation reaction oxygen inlets 102 can make the distribution of the raw material oxidation reaction oxygen more uniform.

[0046] It should be noted that the ignition device 300 and the second raw material oxidation reaction oxygen inlet 102 are both arranged in the conical connecting section 120, and the ignition device 300 is arranged in the area between the second raw material oxidation inlet and the insertion portion of the combustion gun 200.

[0047] The above structural design of the vaporization powder combustion device of this embodiment gives it the following characteristics: the direction of the flame generated by the combustion gun 200 is consistent with the powder spraying direction of the powder raw material, the flame generates little combustion-supporting gas, the powder raw material will hardly burn before leaving the flame area but will be directly vaporized, the temperature, width and length of the flame generated by the combustion gun 200 can be flexibly adjusted to ensure that the powder raw material is completely vaporized before leaving the flame area; the concentration and total flow of oxygen for the combustion reaction outside the flame generated by the combustion gun 200 can be flexibly adjusted; all powder raw materials entering this device are fully vaporized and burned.

[0048] The working principle of the vaporized powder combustion device of this embodiment is: The first step is to introduce raw materials, fuel gas and combustion-supporting gas, ignite and generate a stable flame zone, the internal temperature of the flame exceeds the vaporization temperature of the raw materials, the flame width can completely cover the powder diffusion zone, the flame length can meet the complete vaporization of the powder, the internal combustion-supporting gas of the flame is small, and the outer periphery of the flame is rich in raw material reaction gas. Figure 1 As shown, the light cyan area is a schematic diagram of the powder spray shape, the red area is a schematic diagram of the flame shape, and the blue area is a schematic diagram of the raw material reaction gas (oxygen) shape.

[0049] In the second step, the powdered raw materials are dispersed by the flame-retardant gas, sprayed completely into the flame area, and completely vaporized before leaving the flame area.

[0050] In the third step, the vaporized raw materials leaving the flame area come into contact with oxygen outside the flame, completing vaporization and combustion instantly.

[0051] Second embodiment This embodiment provides a method for preparing nanometer high-purity spherical oxide powder, which includes: using the above-mentioned vaporization powder combustion device to prepare nanometer high-purity spherical oxide powder.

[0052] For reference, the method for preparing nano high-purity spherical oxide powder includes the following steps: Ignite the combustion gun 200 via the ignition device 300; Control the gas flow rate to 45-60 L / min and the flow rate of the supporting gas to maintain the oxygen excess coefficient at 0-10%; The oxidation reaction gas is introduced through the first raw material oxidation reaction oxygen inlet 101 and the second raw material oxidation reaction oxygen inlet 102 at a total flow rate of 600 L / min to 800 L / min, and the ratio of the oxidation reaction gas introduced into the first raw material oxidation reaction oxygen inlet 101 and the second raw material oxidation reaction oxygen inlet 102 is (30-40): (60-70); Feed raw material powder, control the powder injection rate to 30~40kg / h, and the gas-solid ratio to 3.0~4.0.

[0053] Furthermore, the specific operations of the vaporized powder combustion device in the first embodiment are as follows: In the first step, the ignition device 300 is started.

[0054] The second step is to start the combustion gun 200 and inject the fuel gas and the combustion-supporting gas. The initial fuel gas flow rate is set to 10 L / min, and the oxygen ratio of the combustion-supporting gas is set to control the oxygen excess coefficient to 0-20%.

[0055] The third step is to turn off the ignition device 300 and adjust the combustion gun 200. The gas flow rate is gradually adjusted to 45L / min, and the flow rate of the combustion-supporting gas oxygen is automatically adjusted according to the ratio set in the second step.

[0056] The fourth step is to start the first oxygenation device and the second oxygenation device, and set the total flow rate of oxygen for the raw material oxidation reaction and the ratio of the top and side.

[0057] Step 5: Start the powder spraying device and spray the raw material powder (silicon powder). The raw material purity is 99.98%, the particle size D50 is 23.5μm, and the content of particles larger than 150μm is 0.85%. Set the powder spraying rate to 30kg / h. Continue running for more than 24 hours until the machine is shut down.

[0058] Step 6: Conduct testing according to the following sampling, testing and judgment methods.

[0059] Sampling: first piece, 1 hour interval, last piece.

[0060] Method for testing whether a sample contains unburned material: take 1000g sample → 1000 mesh standard water sieve → dry the sieve residue → dry the sieve residue → XRD test to see if it contains raw materials.

[0061] The above operation was performed 10 times according to the different operating parameters in Table 1, and the test results are also shown in Table 1.

[0062] Table 1

[0063] The results in Table 1 show that the products obtained from Groups 2, 4, 7, 9, and 10 all contained unburned raw material. This may be due to the following: In Group 2, the oxygen abundance coefficient was low, meaning too little oxygen was introduced into the combustion gun 200, resulting in a reducing flame and a low flame temperature, which led to incomplete vaporization. In Group 4, the oxygen abundance coefficient was high, meaning too much oxygen was introduced into the combustion gun 200, resulting in a strongly oxidizing flame and a short high-temperature zone, which led to incomplete vaporization. In Group 7, the gas-to-solid ratio of the raw material was too high, resulting in incomplete vaporization. In Group 9, insufficient oxygen was introduced from the side, preventing complete combustion. In Group 10, the large amount of raw material prevented complete vaporization and combustion.

[0064] The XRD test results of group 1 are as follows: Figure 3 There are no impurity peaks other than silica. The XRD test results of group 2 are as follows: Figure 4 , there are other miscellaneous peaks ( Figure 4 (marked by the red line in the figure).

[0065] In summary, the structural design of the combustion gun 200 of the vaporized powder combustion device of the embodiment of the present invention enables the gas gun to produce a stable flame zone, that is, the internal flame temperature exceeds the vaporization temperature of the raw material, the flame width can completely cover the powder diffusion zone, the flame length is sufficient for complete vaporization of the powder, the internal flame contains little combustion-supporting gas, and the outer flame is rich in raw material oxidation reaction oxygen. Specifically, the raw material carrier gas channel 201, the annular gas channel 202, and the annular combustion-supporting gas channel 203 are arranged in the same direction, with the raw material carrier gas channel 201 being located in the center. This can achieve a low internal flame with little combustion-supporting gas after igniting the gas ejected from the combustion gun 200, so that the raw material powder will almost not burn before leaving the flame zone and will directly vaporize. The raw material oxidation reaction oxygen introduced through the first raw material oxidation reaction oxygen inlet 101 at the top and the second raw material oxidation reaction oxygen inlet 102 at the side surrounds the flame zone, allowing the raw material powder to fully contact the raw material oxidation reaction oxygen outside the flame, instantly completing vaporization and combustion, thereby achieving sufficient vaporization and combustion of the powder raw material.

[0066] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. A vaporized powder combustion device, characterized in that: The invention comprises a vaporization combustion chamber and a combustion gun, wherein the vaporization combustion chamber is provided with a combustion gun insertion portion, one end portion of the combustion gun is inserted into the combustion gun insertion portion and communicates with the interior of the vaporization combustion chamber, the combustion gun is sequentially provided with a raw material carrier gas channel, an annular gas channel, and an annular combustion-supporting gas channel from the inside to the outside, the raw material carrier gas channel is provided with a first nozzle at one end located in the vaporization combustion chamber, the annular gas channel is provided with a second nozzle at one end located in the vaporization combustion chamber, the second nozzle is sleeved outside the first nozzle, and a gap is provided between the first nozzle and the second nozzle, and an ignition device for igniting the gas ejected from the second nozzle is provided on the side wall of the vaporization combustion chamber located outside the combustion gun insertion portion; An annular raw material oxidation reaction oxygen inlet channel is provided between the outer wall of the burner gun and the inner wall of the burner gun insertion portion, and a first raw material oxidation reaction oxygen inlet port connected to the annular raw material oxidation reaction oxygen inlet channel is provided on the burner gun insertion portion. The side wall of the vaporization combustion chamber located on the outside of the burner gun insertion portion is provided with at least two second raw material oxidation reaction oxygen inlets evenly spaced, and the angle between the gas introduction direction of the second raw material oxidation reaction oxygen inlet and the central axis of the flame injection direction of the burner gun is 20 to 70 degrees.

2. The vaporized powder combustion device according to claim 1, characterized in that: The burner insertion portion is hollow tubular, and the vaporization combustion chamber is further provided with a conical connecting section, the conical connecting section having a narrowed end connected to the burner insertion portion, the ignition device and the second raw material oxidation reaction oxygen inlet are both provided in the conical connecting section, and the ignition device is provided in the area between the second raw material oxidation inlet and the burner insertion portion.

3. The vaporized powder combustion device according to claim 1, characterized in that: The combustion gun insertion portion is located at the top of the vaporization combustion chamber, and the number of the second raw material oxidation reaction oxygen inlets is at least three, and they are located at the same horizontal height and have the same jet angle.

4. The vaporized powder combustion device according to claim 1, characterized in that: A first annular protrusion for changing the direction of airflow is provided on the outer wall of the first nozzle, and a second annular protrusion for changing the direction of airflow is also provided on the outer wall of the second nozzle.

5. The vaporized powder combustion device according to any one of claims 1 to 4, characterized in that: The combustion gun comprises a raw material inlet pipe, a fuel gas inlet pipe and a combustion-supporting gas inlet pipe which are coaxially sleeved from the inside to the outside.

6. The vaporized powder combustion device according to claim 5, characterized in that: The first nozzle extends from the second nozzle, and the first nozzle is telescopically connected to the raw material inlet pipe, and the second nozzle is telescopically connected to the gas inlet pipe.

7. The vaporized powder combustion device according to any one of claims 1 to 4, characterized in that: The combustion gun is further provided with an annular spare gas channel at intervals outside the annular combustion-supporting gas channel.

8. The vaporized powder combustion device according to any one of claims 1 to 4, characterized in that: The part of the combustion gun located at the combustion gun insertion part is also provided with a cooling channel, and the cooling medium inlet and cooling medium outlet are both located at the upper part of the cooling channel, and are located outside the combustion gun insertion part when installed. A cooling medium inlet pipe is also provided at the cooling medium inlet, and the cooling medium inlet pipe enters the cooling channel and extends downward to the bottom of the cooling channel.

9. A method for preparing nano high-purity spherical oxide powder, characterized in that: It includes: Nano-high-purity spherical oxide powder is prepared using the vaporization powder combustion device according to any one of claims 1 to 8.

10. The method according to claim 9, characterized in that It includes: Ignite the combustion gun by the ignition device; Control the gas flow rate to 45-60 L / min and the flow rate of the supporting gas to maintain the oxygen excess coefficient at 0-10%; The oxidation reaction gas is introduced through the first raw material oxidation reaction oxygen inlet and the second raw material oxidation reaction oxygen inlet at a total flow rate of 600 L / min to 800 L / min, and the ratio of the oxidation reaction gas introduced into the first raw material oxidation reaction oxygen inlet to the second raw material oxidation reaction oxygen inlet is (30-40): (60-70); Feed raw material powder, control the powder injection rate to 30~40kg / h, and the gas-solid ratio to 3.0~4.

0.

11. A nanometer high-purity spherical oxide powder, characterized in that: It is prepared by the method according to claim 9 or 10, and the nano high-purity spherical oxide powder meets the following characteristics: (1) The nano high-purity spherical oxide powder does not contain raw materials that have not been vaporized and combusted; (2) The nano high-purity spherical oxide powder does not contain nitrate ions; (3) The sphericity of the nano high-purity spherical oxide powder is greater than 99%.

Images