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

Abstract

The application discloses a kind of vaporization powder combustion device, nano high-purity spherical oxide powder and its preparation method, the combustion gun of the vaporization powder combustion device is sequentially spaced with raw material carrier gas channel, annular fuel gas channel, annular combustion-supporting gas channel from inside to outside, vaporization combustion chamber is located at the outside of combustion gun insertion part and is provided with ignition device;Combustion gun outer wall and the inner wall between combustion gun insertion part have oxygen inlet channel, vaporization combustion chamber is located at the lateral wall of the outside of combustion gun insertion part and is provided with at least two oxygen inlet ports that are evenly spaced, the included angle between the gas inlet direction of oxygen inlet port and the central axis of the flame injection direction of combustion gun is 20~70 degrees.The device can flexibly adjust the temperature, width length of the flame generated by combustion gun, can ensure that powder raw material is completely vaporized before leaving the flame area, can also flexibly adjust the concentration and total flow of oxygen in the periphery of flame, can realize the sufficient vaporization combustion of powder raw material.

Description

TECHNICAL FIELD

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

[0002] Under the background of rapid development of new energy, electronic devices, aerospace, biomedicine and other high-tech industries, the demand for high-performance materials has shown explosive growth. Nano high-purity spherical oxide powder is widely used in the preparation of high-end functional materials such as ceramics, coatings, catalysts and semiconductors due to its unique physical and chemical properties such as high specific surface area, high activity and uniform morphology. As one of the important processes for preparing such powders, the core technology and key equipment of the vaporized powder combustion method have been owned by foreign countries for a long time, and strict technical protection is implemented.

[0003] The currently disclosed self-developed vaporized powder combustion device has realized the basic function, but there is a technical defect of insufficient combustion in the actual production process, which leads to a large amount of unreacted raw materials remaining in the final product. This phenomenon not only reduces the purity and sphericity of the powder, but also directly affects the performance of the downstream functional materials.

[0004] In view of this, the present application is proposed. SUMMARY

[0005] The purpose of the present application is to provide a vaporized powder combustion device, a nano high-purity spherical oxide powder and a preparation method thereof, in order to improve the above technical problems.

[0006] The present application is realized as follows:

[0007] In a first aspect, the present application provides a vaporized powder combustion device, which comprises a vaporized combustion chamber and a combustion gun, the vaporized combustion chamber is provided with a combustion gun insertion part, one end of the combustion gun is partially inserted into the combustion gun insertion part and the inside of the vaporized combustion chamber is in communication, the combustion gun is sequentially and spacedly provided with a raw material carrier gas channel, an annular fuel gas channel and an annular combustion-supporting gas channel from inside to outside, the raw material carrier gas channel is provided with a first nozzle at one end in the vaporized combustion chamber, the annular fuel gas channel is provided with a second nozzle at one end in the vaporized combustion chamber, the second nozzle is sleeved outside the first nozzle, and a gap is provided between the first nozzle and the second nozzle, the side wall of the vaporized combustion chamber outside the combustion gun insertion part is provided with an ignition device for igniting the fuel gas sprayed out of the second nozzle;

[0008] The outer wall of the combustion gun and the inner wall of the combustion gun insertion part have an annular raw material oxidation reaction oxygen gas inlet channel, and the combustion gun insertion part is provided with a first raw material oxidation reaction oxygen gas inlet port in communication with the annular raw material oxidation reaction oxygen gas inlet channel, and the vaporization combustion chamber is provided with at least two second raw material oxidation reaction oxygen gas inlet ports uniformly distributed on the side wall outside the combustion gun insertion part, and the angle between the gas inlet direction of the second raw material oxidation reaction oxygen gas inlet port and the central axis of the flame jet direction of the combustion gun is 20-70 degrees.

[0009] In some preferred embodiments, the combustion gun insertion part is a hollow pipe, and the vaporization combustion chamber is further provided with a conical connecting section, the narrow end of the conical connecting section is connected with the combustion gun insertion part, the ignition device and the second raw material oxidation reaction oxygen gas inlet port are arranged in the conical connecting section, and the ignition device is arranged in the region between the second raw material oxidation gas inlet port and the combustion gun insertion part.

[0010] In some preferred embodiments, the combustion gun insertion part is located at the top of the vaporization combustion chamber, the number of the second raw material oxidation reaction oxygen gas inlet ports is at least three, and they are located at the same horizontal height and have the same jet angle.

[0011] In some preferred embodiments, the outer wall of the first nozzle is provided with a first annular protrusion for changing the direction of gas flow, and the outer wall of the second nozzle is also provided with a second annular protrusion for changing the direction of gas flow.

[0012] In some preferred embodiments, the combustion gun sequentially comprises a raw material inlet pipe, a fuel gas inlet pipe and a combustion-supporting gas inlet pipe which are coaxially connected from inside to outside.

[0013] In some preferred embodiments, the first nozzle protrudes from the second nozzle, and the first nozzle is telescopically connected with the raw material inlet pipe, and the second nozzle is telescopically connected with the fuel gas inlet pipe.

[0014] In some preferred embodiments, the combustion gun is further provided with an annular standby gas channel which is spaced apart from the annular combustion-supporting gas channel.

[0015] In some preferred embodiments, the part of the combustion gun located in the combustion gun insertion part is further provided with a cooling channel, the cooling medium inlet and the cooling medium outlet are located at the upper part of the cooling channel and are located outside the combustion gun insertion part when installed, and the cooling medium inlet is further provided with a cooling medium inlet pipe which enters the cooling channel and extends downward to the bottom of the cooling channel.

[0016] In a second aspect, the present application further provides a method for preparing nano high-purity spherical oxide powder, which comprises: using the vaporized powder combustion device to prepare nano high-purity spherical oxide powder.

[0017] In some preferred embodiments, the method for preparing nano high-purity spherical oxide powder comprises the following steps:

[0018] igniting the combustion gun by the ignition device;

[0019] controlling the flow of combustion gas to be 45-60 L / min, and controlling the flow of combustion-supporting gas so that the oxygen excess coefficient is maintained at 0-10%;

[0020] passing the oxidation reaction gas through the first raw material oxidation reaction oxygen inlet and the second raw material oxidation reaction oxygen inlet, with a total flow rate of 600-800 L / min, and the ratio of the oxidation reaction gas passed through the first raw material oxidation reaction oxygen inlet to that passed through the second raw material oxidation reaction oxygen inlet being (30-40):(60-70);

[0021] passing the raw material powder, with the powder injection amount being controlled to be 30-40 kg / h, and the gas-solid ratio being controlled to be 3.0-4.0.

[0022] In a third aspect, the present application 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:

[0023] (1) The nano high-purity spherical oxide powder does not contain raw materials for the unvaporized combustion reaction;

[0024] (2) The nano high-purity spherical oxide powder does not contain nitrate ions;

[0025] (3) The sphericity of the nano high-purity spherical oxide powder is greater than 99%.

[0026] The present application has the following beneficial effects: the specific structure of the combustion gun and the structure design of the first raw material oxidation reaction oxygen inlet and the second raw material oxidation reaction oxygen inlet enable the gas gun to generate a stable flame zone, that is, to realize that the internal temperature of the flame exceeds the raw material vaporization temperature, the flame width can completely wrap the powder diffusion zone, the flame length can satisfy the complete vaporization of the powder, the internal combustion-supporting gas of the flame is small, and the flame periphery is rich in raw material oxidation reaction oxygen. Among them, the raw material carrier gas channel, the annular gas channel and the annular combustion-supporting gas channel are arranged in the same direction, and the raw material carrier gas channel is at the center, which can realize that the internal combustion-supporting gas is small after the gas sprayed by the combustion gun is ignited, and the raw material powder hardly burns but directly vaporizes before leaving the flame area; and 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 area, so that the raw material powder can fully contact with the raw material oxidation reaction oxygen (oxygen) outside the flame, complete vaporization and combustion instantaneously, thereby realizing the full vaporization and combustion of the powder raw material. BRIEF DESCRIPTION OF DRAWINGS

[0027] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed to be used in the embodiments will be briefly introduced as follows. It should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can also be obtained without creative labor on the basis of these drawings.

[0028] Figure 1 It is a schematic diagram of the overall structure of the vaporized powder combustion device of the first embodiment of the present application.

[0029] Figure 2 It is a schematic diagram of the structure of the combustion gun of the vaporized powder combustion device of the first embodiment of the present application.

[0030] Figure 3 It is an XRD spectrum of the product of group 1 of the second embodiment of the present application.

[0031] Figure 4 It is an XRD spectrum of the product of group 2 of the second embodiment of the present application.

[0032] Fig. 10 - vaporized powder combustion device; 100 - vaporized combustion chamber; 101 - first raw material oxidizing reaction oxygen inlet; 102 - second raw material oxidizing reaction oxygen inlet; 110 - combustion gun insertion part; 120 - conical connecting section; 200 - combustion gun; 201 - raw material carrier gas passage; 202 - annular fuel gas passage; 203 - annular combustion supporting gas passage; 204 - annular standby gas passage; 205 - cooling passage; 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

[0033] In order to make the objects, technical solutions, and advantages of the embodiments of the present application clearer, the following will be combined with the accompanying drawings for the embodiments of the present application to make a clear and complete description of the technical solutions in the embodiments of the present application. Obviously, the described embodiments are some but not all of the embodiments of the present application. The components of the embodiments of the present application described and shown in the accompanying drawings can be arranged and designed in various different configurations.

[0034] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but only represents selected embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative labor are within the scope of protection of the present application.

[0035] It should be noted that: similar reference numerals and letters represent similar items in the following drawings, therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0036] In the description of the present application, it should be noted that if the terms "upper", "lower", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship when the product of the present application is used, which is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the indicated device or element must have a particular orientation, be constructed and operated in a particular orientation, therefore, it cannot be understood as a limitation on the present application.

[0037] 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.

[0038] 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.

[0039] 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.

[0040] First embodiment

[0041] 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.

[0042] 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.

[0043] 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.

[0044] The vaporization combustion chamber 100 is further provided with a conical connecting section 120, the narrow end of which is connected with the combustion gun insertion part 110. The provision of the conical connecting section 120 can cause a “converging effect” of the gas before entering the reaction zone, and the gas flow rate gradually increases from the bottom of the cone (larger cross-sectional area) to the top (smaller cross-sectional area), forming a turbulent flow or a swirling flow, promoting the molecular-level mixing of different gases, reducing the phenomenon of local over-concentration or over-dilution, to strengthen the gas mixing efficiency and improve the reaction uniformity. In addition, the inclination angle of the conical connecting section 120 (usually designed to be 30°-60°) can reduce the direct collision of the gas with the wall surface, and the high temperature of the conical inner wall is easy to maintain (heat concentration), reducing the condensation and adhesion of the vaporization products on the wall surface.

[0045] Referring to Figure 2 In the embodiment, the combustion gun 200 is sequentially and spacedly provided with a raw material carrier gas channel 201, an annular fuel gas channel 202, and an annular combustion-supporting gas channel 203 from inside to outside. The raw material carrier gas channel 201 is provided with a first nozzle 210 at one end in the vaporization combustion chamber 100, and the annular fuel gas channel 202 is provided with a second nozzle 220 at one end in 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. Through the above structural arrangement, the direction of the raw material spray is consistent with the direction of the flame, and then by adjusting the amount of combustion-supporting gas introduced into the annular combustion-supporting gas channel 203, the amount of combustion-supporting gas in the flame can be reduced, and the powder raw material will not burn but directly vaporize before leaving the flame area.

[0046] Specifically, in the embodiment, the combustion gun 200 sequentially includes a raw material inlet pipe 230, a fuel gas inlet pipe 240, and a combustion-supporting gas inlet pipe 250 which are coaxially arranged. The raw material inlet pipe 230 is a hollow pipe, and the central passage in the inside thereof is the raw material carrier gas channel 201. The carrier gas and the raw material are introduced into the raw material carrier gas channel 201 through the raw material carrier gas inlet 231 at the end thereof, and the raw material is sprayed into the vaporization combustion chamber 100 through the first nozzle 210 under the action of the carrier gas.

[0047] The fuel gas inlet pipe 240 is also a hollow pipe, and the inner wall thereof and the outer wall of the raw material inlet pipe 230 form the annular fuel gas channel 202. The fuel gas is introduced into the annular fuel gas channel 202 through the fuel gas inlet 241 provided at the upper portion of the fuel gas inlet pipe 240, and then sprayed out through the second nozzle 220 connected at the bottom of the fuel gas inlet pipe 240. The upper portion of the raw material inlet pipe 230 and the top portion of the fuel gas inlet pipe 240 are respectively provided with flange structures for connection. The flange structures are welded with the outer wall of the pipe. It should be noted that a sealing structure is provided at the flange connection structure of the two, so as to realize the sealing of the top portion of the annular fuel gas channel 202.

[0048] Further, the first nozzle 210 extends from the second nozzle 220, and the first nozzle 210 is connected with the raw material inlet pipe 230 in an extendable and retractable manner, and the second nozzle is connected with the gas inlet pipe 240 in an extendable and retractable manner, and the gas is sprayed 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 mutual positions of the first nozzle 210 and the second nozzle 220, the gas flow direction can be effectively realized, so as to achieve the purpose of adjusting the flame shape.

[0049] Further, the first nozzle 210 extends from the second nozzle 220, and the first nozzle 210 is connected with the raw material inlet pipe 230 in an extendable and retractable manner, and the second nozzle is connected with the gas inlet pipe 240 in an extendable and retractable manner, and the gas is sprayed 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 mutual positions of the first nozzle 210 and the second nozzle 220, the gas flow direction can be effectively realized, so as to achieve the purpose of adjusting the flame shape.

[0050] The combustion-supporting gas inlet pipe 250 is also a hollow pipe, and the inner wall of the combustion-supporting gas inlet pipe 250 and the outer wall of the gas inlet pipe 240 form an annular combustion-supporting gas passage 203, and the upper portion of the combustion-supporting gas inlet pipe 250 is provided with a combustion-supporting gas inlet 251, and the bottom of the combustion-supporting gas inlet pipe 250 extends above the second nozzle 220, so that the combustion-supporting gas entering through the combustion-supporting gas inlet 251 flows out from the outside of the second nozzle 220 through the annular combustion-supporting gas passage 203. The top of the combustion-supporting gas inlet pipe 250 and the middle and upper portion of the gas inlet pipe 240 are also respectively provided with flange structures for matched connection, and the connection of the flange structures is also provided with a sealing structure, so as to realize the sealing of the top of the annular combustion-supporting gas passage 203. It should be noted that the combustion-supporting gas in the embodiment generally refers to oxygen.

[0051] Through the above structure, the sprayed raw material, gas and combustion-supporting gas can be mixed and sprayed at the outlet end of the combustion gun 200, and the specific powder spraying shape and the specific flame shape can be realized by adjusting the flow and direction of the three kinds of gas.

[0052] In the embodiment, the combustion gun 200 is also provided with an annular standby gas passage 204 outside the annular combustion-supporting gas passage 203, that is, the combustion-supporting gas inlet pipe 250 is further sleeved with a standby gas inlet pipe 260, and the inner wall of the standby gas inlet pipe 260 and the outer wall of the combustion-supporting gas inlet pipe 250 form an annular standby gas passage 204, and the upper portion of the standby gas inlet pipe 260 is provided with a standby gas inlet 261 which is in communication with the annular standby gas passage 204, and the standby gas can be inert gas, and the oxygen concentration can be adjusted by introducing the standby gas, so as to finally realize the purpose of controlling the oxidation reaction rate of the vaporized raw material. The upper portion of the combustion-supporting gas inlet pipe 250 and the top of the standby gas inlet pipe 260 are also respectively provided with flange structures for matched connection, and the connection of the flange structures is also provided with a sealing structure, so as to realize the sealing of the top of the annular standby gas passage 204.

[0053] Further, in the embodiment, the part of the combustion gun 200 located in the insertion part of the combustion gun 200 is also provided with a cooling channel 205, which is formed by the space between the inner wall of the pipeline sleeved on the standby gas inlet pipe 260 and the outer wall of the standby gas 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 located at the upper part of the cooling channel 205 and are located outside the insertion part of the combustion gun 200 when installed. The cooling medium inlet pipe 270 is arranged at the cooling medium inlet 271 and extends into the cooling channel 205 and downward to the bottom of the cooling channel 205, so as to realize the purpose of the cooling medium flowing downward and upward in the cooling channel 205 and improve the cooling efficiency. It should be noted that the cooling medium includes but is not limited to water.

[0054] It should be noted that in the embodiment, the raw material inlet pipe 230, the fuel gas inlet pipe 240, the combustion-supporting gas inlet pipe 250, and the standby gas inlet pipe 260 are coaxially arranged to realize the uniformity of the gas sprayed from the outlet of the pipeline. In addition, the raw material gas inlet 231, the fuel gas inlet 241, the combustion-supporting gas inlet 251, and the standby gas inlet 261 are respectively provided with control devices such as control valves for controlling the flow of the raw material and various gases. In addition, in some embodiments, the standby gas inlet pipe 260 and the cooling channel 205 can be selectively arranged according to actual needs.

[0055] Again referring to Figure 1 The side wall of the vaporization combustion chamber 100 located outside the insertion part 110 of the combustion gun is provided with an ignition device 300 for igniting the fuel gas sprayed by the second nozzle 220. The ignition device 300 is a conventional structure in the art, and will not be described here. The ignition device 300 is arranged in the conical connecting section 120, and the generation of flame can be realized through the ignition device 300.

[0056] The annular raw material oxidation reaction oxygen inlet channel is formed between the outer wall of the combustion gun 200 and the inner wall of the combustion gun insertion part 110, and the first raw material oxidation reaction oxygen inlet 101 is arranged on the combustion gun insertion part 110 and communicates with the annular raw material oxidation reaction oxygen inlet channel. The side wall of the vaporization combustion chamber 100 located outside the insertion part 110 of the combustion gun is provided with at least two second raw material oxidation reaction oxygen inlets 102 which are uniformly spaced. The angle between the gas inlet direction of the second raw material oxidation reaction oxygen inlet 102 and the central axis of the flame spraying direction of the combustion gun 200 is 20-70 degrees. The first raw material oxidation reaction oxygen inlet 101 and the second raw material oxidation reaction oxygen inlet 102 are respectively provided with first oxygen adding devices and second oxygen adding devices, and are provided with control devices for controlling the flow.

[0057] The raw material oxidation reaction oxygen is injected through the top and the side, which is beneficial to the covering of the flame area, so that the vaporized raw material leaving the flame area can fully contact with the raw material oxidation reaction oxygen, and the vaporization combustion is completed instantaneously.

[0058] Further, in the embodiment, the number of the second raw material oxidation reaction oxygen inlets 102 can be three, and they are located at the same height and have the same injection angle. More second raw material oxidation reaction oxygen inlets 102 can be provided in other embodiments. The multiple second raw material oxidation reaction oxygen inlets 102 can make the distribution of the raw material oxidation reaction oxygen more uniform.

[0059] It should be noted that the ignition device 300 and the second raw material oxidation reaction oxygen inlets 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 part of the combustion gun 200.

[0060] The above structure design of the vaporized powder combustion device in the embodiment has the following characteristics: the flame direction generated by the combustion gun 200 is consistent with the powder raw material injection direction, the internal combustion-supporting gas of the flame is small, the powder raw material almost does not burn but directly vaporizes before leaving the flame area, the temperature, width and length of the flame generated by the combustion gun 200 can be flexibly adjusted, the complete vaporization of the powder raw material before leaving the flame area can be ensured, the concentration and total flow of the oxygen for the combustion reaction at the periphery of the flame generated by the combustion gun 200 can be flexibly adjusted, and all the powder raw materials entering the device are subjected to sufficient vaporization combustion.

[0061] The working principle of the vaporized powder combustion device in the embodiment is as follows:

[0062] Firstly, the raw material, the fuel gas and the combustion-supporting gas are introduced, and a stable flame area is generated by ignition, the internal temperature of the flame exceeds the vaporization temperature of the raw material, the width of the flame can completely wrap the powder diffusion area, the length of the flame can satisfy the complete vaporization of the powder, the internal combustion-supporting gas of the flame is small, and the periphery of the flame is rich in raw material reaction gas. Figure 1 As shown in the figure, the light blue area is a schematic diagram of the powder injection 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.

[0063] Secondly, the powder raw material is dispersed by the combustion-supporting gas, and completely injected into the flame area, and completely vaporized before leaving the flame area.

[0064] Thirdly, the vaporized raw material leaving the flame area contacts with the oxygen outside the flame, and the vaporization combustion is completed instantaneously.

[0065] Second embodiment

[0066] The embodiment provides a preparation method of nanometer high-purity spherical oxide powder, which comprises the following steps:

[0067] For reference, the method for preparing nanometer high-purity spherical oxide powder comprises the following steps:

[0068] Ignite the combustion gun 200 through the ignition device 300;

[0069] Control the flow of the combustion gas to be 45-60 L / min, and control the flow of the combustion-supporting gas, so that the oxygen excess coefficient is maintained to be 0-10%;

[0070] Pass the oxidation reaction gas through the first raw material oxidation reaction oxygen inlet 101 and the second raw material oxidation reaction oxygen inlet 102, and the total flow is 600-800 L / min; the proportion of the oxidation reaction gas passed through the first raw material oxidation reaction oxygen inlet 101 and the second raw material oxidation reaction oxygen inlet 102 is (30-40):(60-70);

[0071] Pass the raw material powder, and control the powder spraying amount to be 30-40 kg / h, and the gas-solid ratio is 3.0-4.0.

[0072] Further, the embodiment utilizes the specific operation of the vaporized powder combustion device in the first embodiment, which is as follows:

[0073] First step, start the ignition device 300.

[0074] Second step, start the combustion gun 200, and spray the combustion gas and the combustion-supporting gas. The initial combustion gas flow is set to be 10 L / min, and the oxygen proportion of the combustion-supporting gas is set to control the oxygen excess coefficient to be 0-20%.

[0075] Third step, close the ignition device 300, and adjust the combustion gun 200. Gradually adjust the combustion gas flow to be 45 L / min, and the oxygen flow of the combustion-supporting gas is automatically adjusted according to the proportion set in the second step.

[0076] Fourth step, start the first oxygen adding device and the second oxygen adding device, and set the total flow of the raw material oxidation reaction oxygen and the proportion of the top and the side.

[0077] Fifth step, start the powder spraying device to spray the raw material powder (silicon powder), the purity of the raw material is 99.98%, the particle size D50 is 23.5 μm, the content of >150 μm is 0.85%, and the powder spraying amount is set to be 30 Kg / h. Continue to run for >24 h until shutdown.

[0078] Sixth step, perform detection according to the following sampling, detection method and determination method.

[0079] Sampling: first piece, interval 1 hour, last piece.

[0080] The detection method of whether the sample contains unburned material is as follows: 1000 g of sample is taken, 1000 mesh standard sieve water screen, the residue is dried, the dried residue is detected by XRD to determine whether the raw material is contained.

[0081] The above operation is carried out for 10 groups according to different operation parameters in Table 1, and the detection results are also shown in Table 1.

[0082] Table 1

[0083]

[0084] From the results in Table 1, it can be seen that the products obtained in groups 2, 4, 7, 9 and 10 all contain unburned raw materials. The reasons for this result may be as follows: in group 2, the oxygen excess coefficient is low, that is, too little oxygen is introduced into the combustion gun 200, the flame belongs to reducing flame, the flame temperature is reduced, and thus the vaporization is insufficient. In group 4, the oxygen excess coefficient is high, that is, too much oxygen is introduced into the combustion gun 200, the flame belongs to strong oxidizing flame, the high temperature zone is short, and thus the vaporization is insufficient. In group 7, the gas-solid ratio of the raw material is too high, which leads to insufficient vaporization. In group 9, the oxygen introduced from the side is insufficient, which fails to achieve sufficient combustion. In group 10, the amount of raw material is large, which fails to achieve sufficient vaporization and combustion.

[0085] The XRD detection result of group 1 is as shown in Figure 3 , and there is no impurity peak other than silicon dioxide, the XRD detection result of group 2 is as shown in Figure 4 , and there is other impurity peak (the red line in Figure 4 ).

[0086] In summary, the structure design of the combustion gun 200 of the vaporization powder combustion device of the embodiment of the present application makes the gas gun be able to generate a stable flame zone, that is, the internal temperature of the flame exceeds the vaporization temperature of the raw material, the width of the flame can completely wrap the powder diffusion zone, the length of the flame can satisfy the complete vaporization of the powder, the internal combustion-supporting gas of the flame is little, and the periphery of the flame is rich in raw material oxidation reaction oxygen. Among them, 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, and the raw material carrier gas channel 201 is at the center, which can realize that the internal combustion-supporting gas is little after the gas sprayed from the combustion gun 200 is ignited, and the raw material powder almost does not burn but directly vaporizes before leaving the flame area; and 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 area, so that the raw material powder can be in contact with the raw material oxidation reaction oxygen outside the flame, and the vaporization and combustion are completed instantaneously, thereby realizing the sufficient vaporization and combustion of the powder raw material.

[0087] The above merely provides the preferred embodiments of the present application, and is not used to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the principles and technical scope of the present application shall fall into the scope of the present application.

Claims

1. A pulverized fuel combustion apparatus, characterized by comprising: It includes a vaporization combustion chamber and a combustion gun, the vaporization combustion chamber is provided with a combustion gun insertion part, one end of the combustion gun is inserted into the combustion gun insertion part and the inside of the vaporization combustion chamber, the combustion gun is sequentially and spaced provided with a raw material carrier gas channel, an annular fuel gas channel and an annular combustion supporting gas channel from inside to outside, the raw material carrier gas channel is provided with a first nozzle at one end in the vaporization combustion chamber, the annular fuel gas channel is provided with a second nozzle at one end in the vaporization combustion chamber, the second nozzle is sleeved outside the first nozzle, and a gap is arranged between the first nozzle and the second nozzle, the side wall of the vaporization combustion chamber outside the combustion gun insertion part is provided with an ignition device for igniting the fuel gas sprayed out of the second nozzle, after the fuel gas sprayed out of the combustion gun is ignited, the inside of the flame is realized to be less combustion supporting gas, and the raw material powder is directly vaporized before leaving the flame area. The outer wall of the combustion gun and the inner wall of the combustion gun insertion part have an annular raw material oxidation reaction oxygen inlet channel, and the combustion gun insertion part is provided with a first raw material oxidation reaction oxygen inlet port communicated with the annular raw material oxidation reaction oxygen inlet channel, and the side wall of the vaporization combustion chamber outside the combustion gun insertion part is provided with at least two second raw material oxidation reaction oxygen inlet ports uniformly distributed, the angle between the gas inlet direction of the second raw material oxidation reaction oxygen inlet port and the central axis of the flame jet direction of the combustion gun is 20-70 degrees, and the raw material oxidation reaction oxygen inlet through the first raw material oxidation reaction oxygen inlet port at the top and the second raw material oxidation reaction oxygen inlet port at the side surrounds the flame area, so that the raw material powder can fully contact with the raw material oxidation reaction oxygen outside the flame, and the vaporization combustion is completed instantaneously, thereby realizing the full vaporization combustion of the powder raw material.

2. The pulverized fuel combustion apparatus according to claim 1, wherein The combustion gun insertion part is a hollow tubular, the vaporization combustion chamber is further provided with a conical connecting section, the necked end of the conical connecting section is connected with the combustion gun insertion part, the ignition device and the second raw material oxidation reaction oxygen inlet port are arranged in the conical connecting section, and the ignition device is arranged in the region between the second raw material oxidation inlet port and the combustion gun insertion part.

3. The gasified powder combustion device according to claim 1, wherein The combustion gun insertion part is located at the top of the vaporization combustion chamber, the number of the second raw material oxidation reaction oxygen inlet ports 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, wherein The outer wall of the first nozzle is provided with a first annular protrusion for changing the direction of gas flow, and the outer wall of the second nozzle is also provided with a second annular protrusion for changing the direction of gas flow.

5. The pulverized solid fuel combustion apparatus according to any one of claims 1 to 4, characterized by The combustion gun sequentially includes a raw material inlet pipe, a fuel gas inlet pipe and a combustion supporting gas inlet pipe which are coaxially sleeved from inside to outside.

6. The pulverized solid fuel combustion apparatus according to claim 5, wherein The first nozzle protrudes from the second nozzle, and the first nozzle is telescopically connected with the raw material inlet pipe, and the second nozzle is telescopically connected with the fuel gas inlet pipe.

7. The pulverized solid fuel combustion apparatus according to any one of claims 1 to 4, characterized by The combustion gun is further spaced provided with an annular standby gas channel outside the annular combustion supporting gas channel.

8. The pulverized solid fuel combustion apparatus according to any one of claims 1 to 4, characterized by The combustion gun is located in the part of the combustion gun insertion part, which is also provided with a cooling channel, a cooling medium inlet and a cooling medium outlet, which are located at the upper part of the cooling channel and are located outside the combustion gun insertion part during installation, and a cooling medium inlet pipe is arranged at the cooling medium inlet, which 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 comprises: The nanometer high-purity spherical oxide powder is prepared by using the vaporized powder combustion device according to any one of claims 1-8.

10. The method of claim 9, wherein, It comprises: Ignite the combustion gun by the ignition device; Control the flow of the combustion gas to be 45-60 L / min, and control the flow of the combustion-supporting gas so that the oxygen excess coefficient is maintained at 0-10%; Pass the oxidation reaction gas through the first raw material oxidation reaction oxygen inlet and the second raw material oxidation reaction oxygen inlet, and the total flow is 600-800 L / min, and the ratio of the oxidation reaction gas passed through the first raw material oxidation reaction oxygen inlet and the second raw material oxidation reaction oxygen inlet is (30-40):(60-70); Pass the raw material powder, and control the powder injection amount to be 30-40 kg / h, and the gas-solid ratio is 3.0-4.

0.

11. A nano high purity spherical oxide powder, characterized in that, The nanometer high-purity spherical oxide powder prepared by the method of claim 9 or 10 meets the following characteristics: (1) The nanometer high-purity spherical oxide powder does not contain raw materials of unvaporized combustion reaction; (2) The nanometer high-purity spherical oxide powder does not contain nitrate ions; (3) The nanometer high-purity spherical oxide powder has a sphericity of greater than 99%.

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