Nano coating preparation system and preparation method thereof

Abstract

The invention discloses a nano coating preparation system which comprises an aerosol preparation system, a centrifugal container system and an aerosol conveying and processing system, the aerosol preparation system can disperse nano particles into a gas medium to generate nano aerosol; a surface connecting device is arranged at an outlet of the centrifugal container system, the surface connecting device can be connected with a surface to be sprayed, and the nano aerosol enters the centrifugal container system, centrifugally rotates in the centrifugal container system and impacts on the surface to be sprayed through the surface connecting device to form a nano coating; the aerosol conveying and processing system is connected with the aerosol preparation system and the centrifugal container system, and the aerosol conveying and processing system is used for processing charges carried by particles of the nano aerosol generated by the aerosol preparation system and conveying the nano aerosol into the centrifugal container system.

Description

Technical Field

[0001] The present invention relates to the technical field of coating preparation, and in particular to a nano coating preparation system and a preparation method thereof. Background Art

[0002] Nano coatings can be used for surface modification and optimization of surface properties. There are many methods for preparing nano coatings for applications in different industries, such as electrochemical deposition, LB film forming technology, brush plating, thermal spraying, etc. Among them, in the application of mitigation measures for severe accidents in the nuclear energy field, the required nano coatings have low requirements for structural strength and are only put into use when an accident occurs to enhance the critical heat flux (CHF); on the contrary, more attention is paid to the preparation cost, operation and daily maintenance convenience of the nano coatings. In the prior art, there are few technologies available for the preparation of the nano coatings required in the nuclear energy field.

[0003] Patent DE2808903A1 proposes a method for coating a homogeneous plastic coating on the inner wall of a pipe and a device for implementing the method, using the centrifugal force of a distributor to form fine droplets or aerosols, and forming a uniform polymer coating on the inner wall of the pipe. The difference between this application and patent DE2808903A1 is that: 1) the patent is not applicable to the use of nanoparticles, and the nanoparticles need to be dehumidified and then prepared into aerosols by an aerosol generator, not by centrifugal force; 2) in order to maintain the dispersion characteristics of the aerosol, it is also necessary to eliminate static electricity, carry charge, and low-pressure treatment. The content of this invention needs to be summarized from the experience of preparing aerosols in the laboratory; 3) centrifugal acceleration is to give the aerosol a certain initial velocity to hit the target surface; 4) the aerosol hits the target surface, and the nanocoating is formed by using the pores of the target surface and the adsorption of nanoparticles. The principle of coating formation is obviously different.

[0004] Prior art CN118321043A discloses a nano coating preparation spraying system and a method for forming a nano coating, wherein the nano fluid treated by a pressurizing system and a heating system is sprayed onto a target surface through a fluid acceleration device to form a nano coating. This application aims to provide a nano coating preparation method suitable for the nuclear energy field with simpler operation and lower cost.

[0005] In view of the above technical problems, the present invention is specially introduced. Summary of the invention

[0006] The main purpose of the present invention is to provide a nano coating preparation system and a preparation method thereof, so as to solve the above technical problems.

[0007] In order to achieve the above-mentioned purpose, according to the first aspect of the present invention, a nano-coating preparation system is proposed, comprising the following parts: an aerosol preparation system, which can disperse nanoparticles into a gas medium to produce nano-aerosol; a centrifugal container system, wherein a surface connection device is provided at the outlet of the centrifugal container system, and the surface connection device can be connected to the surface to be sprayed, and the nano-aerosol enters the centrifugal container system, undergoes centrifugal rotation in the centrifugal container system, and impacts the surface to be sprayed through the surface connection device to form a nano-coating; an aerosol transport and processing system, wherein the aerosol transport and processing system is connected to both the aerosol preparation system and the centrifugal container system, and the aerosol transport and processing system processes the charge carried by the particles of the nano-aerosol generated by the aerosol preparation system, and transports the nano-aerosol to the centrifugal container system.

[0008] Furthermore, the aerosol transport and processing system includes a transport channel and a static eliminator. The static eliminator is arranged on the transport channel and located downstream of the aerosol preparation system. The static eliminator can eliminate the charge carried by the nano aerosol particles.

[0009] Furthermore, the aerosol transport processing system also includes a diffuser charger arranged on the transport channel, the diffuser charger is arranged downstream of the static eliminator, and the diffuser charger makes the nano aerosol particles carry the same type of charge.

[0010] Furthermore, the diffuser charger can emit gamma or x-rays to process the nano aerosol particles so that their energy is between 2keV and 9.8keV.

[0011] Furthermore, the aerosol transport and processing system includes a carrier gas supply device, which is located at the end of the transport channel and can provide a carrier gas with adjustable air pressure into the transport channel.

[0012] Furthermore, the aerosol preparation system includes an aerosol generator, the outlet of the aerosol generator is connected to the delivery channel, and the aerosol delivery processing system also includes a dehumidifier arranged on the delivery channel, and the dehumidifier is arranged between the carrier gas supply device and the aerosol generator.

[0013] Furthermore, the centrifugal container system includes an aerosol centrifugal tank, the side wall of which is formed by a tank body arc section, a tank body vertical section and a tank body horizontal section connected in sequence, the tank body vertical section and the tank body horizontal section are both tangent to the tank body arc section, the radius R of the tank body arc section, the length L of the tank body vertical section, and the length D of the tank body horizontal section satisfy: R=L=D.

[0014] Furthermore, the surface connection device is arranged on a side of the vertical section of the tank body close to the horizontal section of the tank body, and the surface connection device includes an elastic material and can be sealed and fitted with the surface to be sprayed.

[0015] Furthermore, a rectifying component for guiding the flow direction of the nano aerosol is also provided in the aerosol centrifugal tank, and a vertical flow channel is formed between the outer wall of at least one rectifying component and the inner wall of the vertical section of the tank body, and a horizontal flow channel is formed between the outer wall of at least one rectifying component and the inner wall of the horizontal section of the tank body.

[0016] Furthermore, a replaceable guide plate is provided in the horizontal flow channel, and the guide plate can be a porous structure guide plate, a Rafale guide plate or a streamlined guide plate.

[0017] Furthermore, a paddle-type agitator is arranged in the aerosol centrifugal tank. The paddle-type agitator is made of ceramic, carbon fiber and / or conductive polymer, and the rotation speed of the paddle-type agitator can be adjusted.

[0018] Furthermore, the aerosol centrifugal tank is also connected to a vacuum system, and the vacuum system includes an isolation valve and a vacuum pump.

[0019] In order to achieve the above-mentioned purpose, according to the second aspect of the present invention, a method for preparing a nanocoating is proposed, which adopts the nanocoating preparation system according to the above-mentioned method and includes the following steps: a nanoaerosol preparation step, dispersing nanoparticles into a gas medium to prepare a nanoaerosol; a nanoaerosol treatment step, eliminating the charge carried by the particles of the nanoaerosol and making them all carry positive or negative charges; a centrifugal spraying step, driving the nanoaerosol to perform centrifugal acceleration so that the nanoaerosol impacts on the surface to be sprayed after acceleration to form a nanocoating.

[0020] Furthermore, in the centrifugal spraying step, the ambient pressure of the nanoaerosol is between 0.4 bar and 0.5 bar before the nanoaerosol is centrifugally accelerated.

[0021] Furthermore, the nano aerosol particles include metal single substance particles, metal oxide particles and / or non-metal oxide particles with a particle size not greater than 100 nm.

[0022] By applying the technical solution of the present invention, at least the following beneficial effects are achieved:

[0023] 1. The present invention provides an aerosol preparation system, an aerosol transport and processing system, and a centrifugal container system to give a certain initial velocity to the nano aerosol that has been dehumidified and charged under low pressure conditions, so that it hits the target surface to form a nano coating. The nano coating can effectively enhance the critical heat flux density of the target surface and greatly improve the heat exchange margin.

[0024] 2. The present invention provides an electrostatic eliminator and a diffuser on the conveying channel, so that the nanoaerosol particles carry the same type of positive or negative charge, and control the treatment measures such as low pressure environment, which greatly improves the uniformity of nanoaerosol dispersion, effectively reduces the aggregation and sedimentation of aerosol, and improves the efficiency of preparing nano-coating.

[0025] 3. The present invention designs the outer shell and internal structure of the aerosol centrifuge tank, and uses rectifiers to match various forms of guide plates. Nano-coatings with different properties can be prepared by changing the structural form of the guide plates to meet the needs of more application scenarios, making the present invention have a wide range of applications.

[0026] 4. The present invention provides a vacuum environment by setting up a vacuum system and a variable frequency paddle agitator, so as to control the concentration of nano aerosol in the aerosol centrifugal tank, thereby preparing nano coatings with different requirements; and the vacuum environment greatly reduces the initial water vapor content, reduces the aerosol hygroscopic growth, condensation and deposition; and also reduces the resistance to the centrifugal motion of the aerosol, so as to obtain a higher centrifugal speed.

[0027] 5. The present invention designs a nano-coating preparation system and method, and the operation of preparing the nano-coating is simple, low-cost, and highly efficient, and the preparation system is easy to maintain. The nano-coating is particularly suitable for preparing the nano-coating for use in the nuclear energy field. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:

[0029] Figure 1 A schematic diagram of a nano coating preparation system according to Example 1 of the present invention is shown;

[0030] Figure 2 The schematic diagram of the outline structure of the aerosol centrifugal tank of Example 1 of the present invention is shown;

[0031] Figure 3 A schematic diagram of the centrifugal movement of nanoaerosols according to Example 1 of the present invention is shown;

[0032] Figure 4 A schematic diagram showing a guide plate of Example 2 of the present invention being placed in an aerosol centrifugal tank;

[0033] Figure 5 A schematic diagram of a guide plate according to Embodiment 2 of the present invention is shown;

[0034] Figure 6 A schematic diagram showing a guide plate of Example 3 of the present invention being placed in an aerosol centrifugal tank;

[0035] Figure 7 A schematic diagram of a guide plate according to Embodiment 3 of the present invention is shown;

[0036] Figure 8 A schematic diagram showing a guide plate of Example 4 of the present invention being placed in an aerosol centrifugal tank;

[0037] Fig. 9 A schematic diagram of a guide plate according to embodiment 4 of the present invention is shown.

[0038] The above drawings include the following reference numerals:

[0039] 1. Aerosol preparation system; 11. Aerosol generator;

[0040] 2. Centrifugal container system; 21. Aerosol centrifugal tank; 22. Tank arc section; 23. Tank vertical section; 24. Tank horizontal section; 25. Regulator; 26. Vertical flow channel; 27. Horizontal flow channel; 28. Guide plate; 28a. Porous structure guide plate; 28b. Rafale guide plate; 28c. Streamlined guide plate; 29. ​​Paddle agitator;

[0041] 3. Aerosol transport and processing system; 31. Transport channel; 32. Static eliminator; 33. Diffusive charger; 34. Carrier gas supply equipment; 35. Dehumidifier;

[0042] 4. Surface connection device; 5. Surface to be sprayed; 6. Vacuum extraction system; 61. Isolation valve; 62. Vacuum pump; 7. First ring area inside the tank body; 8. Second ring area inside the tank body; 9. Third ring area inside the tank body; 10. Fourth ring area inside the tank body. DETAILED DESCRIPTION

[0043] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0044] The present invention is further described in detail below in conjunction with specific embodiments, and these embodiments cannot be understood as limiting the scope of protection claimed by the present invention. The term "including" when used indicates the existence of a feature, but does not exclude the existence or addition of one or more other features; the orientation or position relationship indicated by the terms "lateral", "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inside", "outside", etc. is based on the orientation or position relationship shown in the drawings, which is only for the convenience of 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, and therefore cannot be understood as a limitation on the present invention; in addition, the terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance.

[0045] In the description, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. In addition, in the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0046] Embodiment 1:

[0047] The present invention proposes a nano coating preparation system, such as Figure 1 As shown, the system includes the following parts:

[0048] The aerosol preparation system 1 can disperse selected types of nanomaterial particles, such as metal copper particles, aluminum oxide particles, silicon carbide particles, etc., into a gas medium to generate nano aerosol.

[0049] A centrifugal container system 2 is provided with a surface connecting device 4 at the outlet of the centrifugal container system 2, and the surface connecting device 4 can be connected to the surface to be sprayed 5. The nano aerosol enters the centrifugal container system 2 and is centrifugally rotated in the centrifugal container system 2, so that the nano aerosol is accelerated and reaches a certain initial velocity, and then impacts the surface to be sprayed 5 through the surface connecting device 4 to form a nano coating.

[0050] The aerosol transport and processing system 3 is connected to the aerosol preparation system 1 and the centrifugal container system 2. The aerosol transport and processing system 3 processes the charges carried by the particles of the nano aerosol generated by the aerosol preparation system 1 and transports the nano aerosol to the centrifugal container system 2.

[0051] Specifically, the aerosol transport and processing system 3 includes a transport channel 31, a static eliminator 32, and a carrier gas supply device 34. The carrier gas supply device 34 is located at the end of the transport channel 31 and can provide a carrier gas with adjustable air pressure to the transport channel 31. The static eliminator 32 is arranged on the transport channel 31 and is located downstream of the aerosol preparation system 1. The static eliminator 32 can eliminate the charge carried by the nano aerosol particles.

[0052] Preferably, in this embodiment, the carrier gas supply device 34 uses an air compressor, which can provide a carrier gas with a pressure of not less than 2 bar and the size can be flexibly adjusted. In some other embodiments, a gas source and a high-pressure gas cylinder or other equipment can also be used to provide a carrier gas to bring the nanoaerosol generated by the aerosol preparation system 1 into the centrifugal container system 2.

[0053] Further, the aerosol preparation system 1 uses an aerosol generator 11, and the outlet of the aerosol generator 11 is connected to the delivery channel 31. The aerosol generator can support the carrier gas to carry out aerosol particles with a particle size d≤100nm, and the types of particles include but are not limited to metal elements, metal oxides, non-metal oxides, such as metal copper particles, aluminum oxide particles, silicon carbide particles, etc. In some other embodiments, the aerosol preparation system 1 can also use some physical and chemical methods such as atomization to prepare nano aerosols.

[0054] The aerosol transport processing system 3 further includes a dehumidifier 35 disposed on the transport channel 31, and the dehumidifier 35 is disposed between the carrier gas supply device 34 and the aerosol generator 11. The dehumidifier 35 removes water vapor in the carrier gas to reduce the aerosol's hygroscopic growth, condensation and deposition.

[0055] Preferably, the aerosol transport and processing system 3 further includes a diffuser 33 disposed on the transport channel 31, and the diffuser 33 is disposed downstream of the static eliminator 32. The diffuser 33 allows the nano aerosol particles to carry the same type of positive or negative charge, thereby greatly improving the uniformity of nano aerosol dispersion, effectively reducing aerosol aggregation and sedimentation, and improving the efficiency of preparing nano coatings.

[0056] Further preferably, the diffuser 33 can emit gamma or x-rays to process the nano aerosol particles, so that their energy is between 2keV and 9.8keV. Experimental verification shows that in this case, the uniformity of nano aerosol dispersion is better, and less aggregation and sedimentation occurs.

[0057] In addition, after the carrier gas supply device 34 of the present application is pressure-regulated, the carrier gas passes through the dehumidifier 35, the aerosol generator 11, the static eliminator 32 and the diffuser 33, so that the air pressure P1 entering the centrifugal container system 2 satisfies 0.4 bar ≤ P1 ≤ 0.5 bar. It has been verified by experiments that the condensation and deposition of aerosol particles can be reduced in a low pressure environment of 0.4-0.5 bar.

[0058] The present invention provides an aerosol preparation system, an aerosol transport and processing system and a centrifugal container system, and gives a certain initial velocity to the nano aerosol that has been dehumidified, destaticized and charged under low pressure conditions, thereby increasing its impact force and causing it to impact the target surface to form a nano coating. The nano coating can effectively enhance the critical heat flux density of the target surface and greatly improve the heat exchange margin.

[0059] Combination Figure 2 and Figure 3As shown, the centrifugal container system 2 includes an aerosol centrifugal tank 21, and the side wall of the aerosol centrifugal tank 21 is formed by sequentially connecting a tank body arc section 22, a tank body vertical section 23, and a tank body horizontal section 24. Preferably, the tank body vertical section 23 and the tank body horizontal section 24 are both tangent to the tank body arc section 22, that is, the radius R of the tank body arc section 22, the length L of the tank body vertical section 23, and the length D of the tank body horizontal section 24 satisfy: R = L = D. Preferably, R ≥ 1.5m.

[0060] Furthermore, a paddle stirrer 29 is provided in the aerosol centrifugal tank 21. The paddle stirrer 29 is made of antistatic material, such as ceramic, carbon fiber and / or conductive polymer, and the rotation speed can be adjusted as needed to reduce the deposition of aerosol due to static electricity, and to facilitate the adjustment of the initial velocity of the aerosol as needed, and can also be used to adjust the concentration of aerosol particles.

[0061] The surface connection device 4 is arranged on one side of the tank body vertical section 23 close to the tank body horizontal section 24. The surface connection device 4 comprises an elastic material, so that the surface connection device 4 has a certain elasticity and can be well sealed and fitted with the surface to be sprayed 5. A rectifying member 25 for guiding the flow direction of the nano aerosol is also arranged in the aerosol centrifugal tank 21. A vertical flow channel 26 is formed between the outer wall of at least one rectifying member 25 and the inner wall of the tank body vertical section 23, and a horizontal flow channel 27 is formed between the outer wall of at least one rectifying member 25 and the inner wall of the tank body horizontal section 24.

[0062] From above, Figure 3 As shown, the nano aerosol in the aerosol centrifugal tank 21 gradually forms a stratified phenomenon after being evenly and stably distributed under the action of the paddle stirrer 29. Under the action of centrifugal force, the closer the aerosol concentration is to the side wall of the aerosol centrifugal tank 21, the higher the concentration is, that is, the concentration λ1 of the first ring area 7 in the tank body, the concentration λ2 of the second ring area 8 in the tank body, the concentration λ3 of the third ring area 9 in the tank body, and the concentration λ4 of the fourth ring area 10 in the tank body satisfy the following relationship: λ1<λ2<λ3<λ4. The nano aerosol in the fourth ring area 10 in the tank body rotates at a certain speed, and under the guidance of the rectifying part 25, it moves along the horizontal flow channel 27 to vertically impact the surface to be sprayed 5, and then the remaining nano aerosol continues to circulate along the vertical flow channel 26. In this way, the cycle is repeated, and a nano coating is formed on the surface to be sprayed 5 by continuously impacting the surface to be sprayed 5.

[0063] Furthermore, the aerosol centrifugal tank 21 is also connected to a vacuum system 6, which includes an isolation valve 61 and a vacuum pump 62. Before the aerosol enters the aerosol centrifugal tank 21, the aerosol centrifugal tank 21 is first vacuumed by the vacuum system 6, so that the internal pressure P0 of the aerosol centrifugal tank 21 is less than 2.5 Pa. The vacuum environment greatly reduces the initial water vapor content, reduces the aerosol hygroscopic growth, condensation and deposition; and also reduces the resistance to the centrifugal motion of the aerosol, so as to obtain a higher centrifugal speed.

[0064] The present invention also proposes a method for preparing a nano coating, which uses the nano coating preparation system described above and includes the following steps:

[0065] The nanoaerosol preparation step S1 disperses nanoparticles into a gas medium to prepare a nanoaerosol; the nanoaerosol treatment step S2 eliminates the charge carried by the nanoaerosol particles and makes them all carry positive or negative charges; the centrifugal spraying step S3 drives the nanoaerosol to be centrifugally accelerated so that the nanoaerosol reaches a certain initial velocity and then impacts the surface to be sprayed 5 to form a nano coating.

[0066] Specifically, for the nano coating preparation method proposed in this embodiment, the lower head of the nuclear reactor pressure vessel is used as the spraying object, and the specific operation steps are as follows:

[0067] In the nano-aerosol preparation step S1, the selected nano-particles, such as metal copper particles, aluminum oxide particles, silicon carbide particles, etc., which have been dried, are loaded into the aerosol generator 11. The aerosol generator 11 can disperse the nano-particles into nano-aerosols. The microparticles of the nano-aerosols include metal single-substance particles, metal oxide particles and / or non-metal oxide particles, etc., with a particle size not greater than 100 nm.

[0068] Connect the surface connection device 4 of the aerosol centrifugal tank 21 to the surface of the lower head of the reactor pressure vessel. Open the carrier gas supply device 34 and adjust the carrier gas pressure so that the actual gas supply pressure P1 after the carrier gas passes through the dehumidifier 35, the aerosol generator 11, the static eliminator 32 and the diffuser charger 33 satisfies 0.4bar≤P1≤0.5bar. Open the isolation valve 61, start the vacuum pump 62, and draw the pressure in the aerosol centrifugal tank 21 to a near vacuum state, that is, the initial internal pressure P0<2.50Pa, and then close the vacuum pump 62 and the isolation valve 61.

[0069] In the nano-aerosol processing step S2, the carrier gas flow rate provided by the carrier gas supply device 34 is not less than 5 L / min, and the nano-aerosol generated by the aerosol generator 11 is taken out, and after passing through the dehumidifier 35 for dehumidification treatment, the static electricity is removed by the static eliminator 32, and the charge is charged by the diffuser 33 on the conveying channel 31, it is injected into the aerosol centrifugal tank 21. The temperature of the nano-aerosol in the aerosol centrifugal tank 21 is lower than 80°C.

[0070] When the pressure P2 in the aerosol centrifugal tank 21 reaches 0.4 bar ≤ P2 ≤ 0.5 bar, the actual gas supply pressure P1 is the same as the pressure P2 in the aerosol centrifugal tank 21 (P1 = P2), and the gas supply ends. At this time, the nano aerosol fills the entire space in the aerosol centrifugal tank 21 relatively evenly.

[0071] In the centrifugal spraying step S3, the paddle stirrer 29 is turned on, and after being uniform and stable, the aerosol gradually forms a stratification phenomenon. Preferably, after the outermost layer of nano aerosol reaches an initial velocity of 2 m / s, it passes through the surface connection device 4 and impacts on the surface of the reactor pressure vessel lower head to form a nano coating. The same method is used to repeat the operation on other positions of the outer wall surface of the reactor pressure vessel lower head until the entire surface is formed with a nano coating.

[0072] The technical solution of the present application combines the characteristics of laboratory aerosol preparation and the in-core melt retention strategy (IVR) and the extra-core melt retention strategy (EVR) of severe accidents in pressurized water reactor nuclear power plants, and prepares a nano-coating on the target surface to improve the heat exchange margin, thereby improving the safety of pressurized water reactor nuclear power plants. It has many advantages such as low cost, convenient operation, and easy maintenance.

[0073] Embodiment 2:

[0074] The preparation method and preparation system of the nano coating in this embodiment are the same as those described in Example 1, except that: Figure 4 As shown, a guide plate 28 is also provided in the aerosol centrifugal tank 21, and the guide plate 28 is provided in the horizontal flow channel 27 and close to the surface connection device 4. It can be arranged to be fixedly connected to the inner wall of the aerosol centrifugal tank 21 or the rectifying member 25. Holes are provided on the guide plate so that the nano aerosol passes through the guide plate 28 and enters the surface connection device 4. The design of the rectifying member and the guide plate 28 can be used to prepare a nano coating with a desired special structure.

[0075] like Figure 5 As shown, the guide plate 28 of this embodiment is configured as a porous structure guide plate 28a, and a plurality of holes are provided on the porous structure guide plate 28a. Figure 5 The porous structure guide plate shown can be used to prepare a nano coating with non-uniform thickness. The size, number and position of the holes on the porous structure guide plate can also be designed in other forms.

[0076] Embodiment 3:

[0077] The preparation method and system of the nano coating in this embodiment are the same as those described in Embodiment 1 and Embodiment 2, except that the guide plate 28 is replaceable, and the form, position and angle of the guide plate can be adjusted according to actual needs. The nano coating structure prepared by using guide plates of different forms, positions and angles is also different.

[0078] Combination Figure 6 and Figure 7As shown, the guide plate of this embodiment is a Rafale guide plate 28b, on which a channel of a Rafale nozzle structure is arranged. By adjusting the position and angle of the Rafale guide plate 28b, a nano coating with a loose structure can be produced.

[0079] Embodiment 4:

[0080] The preparation method and preparation system of the nano coating in this embodiment are the same as those described in Embodiment 1, Embodiment 2 and Embodiment 3, except that the nano coating is combined with Figure 8 and Fig. 9 As shown, the guide plate of this embodiment is a streamlined guide plate 28c.

[0081] By matching the fairing 25 with various forms of guide plates 28, nano coatings with different properties can be prepared by changing the structural form, position and angle of the guide plates to meet the needs of more application scenarios, thus making the application scope of the present invention wide.

[0082] In summary, from the above description, it can be seen that the above embodiments of the present invention achieve the following technical effects:

[0083] 1. The present invention provides an aerosol preparation system, an aerosol transport and processing system, and a centrifugal container system to give a certain initial velocity to the nano aerosol that has been dehumidified and charged under low pressure conditions, so that it hits the target surface to form a nano coating. The nano coating can effectively enhance the critical heat flux density of the target surface and greatly improve the heat exchange margin.

[0084] 2. The present invention provides an electrostatic eliminator and a diffuser on the conveying channel, so that the nanoaerosol particles carry the same type of positive or negative charge, and control the treatment measures such as low pressure environment, which greatly improves the uniformity of nanoaerosol dispersion, effectively reduces the aggregation and sedimentation of aerosol, and improves the efficiency of preparing nano-coating.

[0085] 3. The present invention designs the outer shell and internal structure of the aerosol centrifuge tank, and uses rectifiers to match various forms of guide plates. Nano-coatings with different properties can be prepared by changing the structural form of the guide plates to meet the needs of more application scenarios, making the present invention have a wide range of applications.

[0086] 4. The present invention provides a vacuum environment by setting up a vacuum system and a variable frequency paddle agitator, so as to control the concentration of nano aerosol in the aerosol centrifugal tank, thereby preparing nano coatings with different requirements; and the vacuum environment greatly reduces the initial water vapor content, reduces the aerosol hygroscopic growth, condensation and deposition; and also reduces the resistance to the centrifugal motion of the aerosol, so as to obtain a higher centrifugal speed.

[0087] 5. The present invention designs a nano-coating preparation system and method, and the operation of preparing the nano-coating is simple, low-cost, and highly efficient, and the preparation system is easy to maintain. The nano-coating is particularly suitable for preparing the nano-coating for use in the nuclear energy field.

[0088] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A nano coating preparation system, It is characterized in that Includes the following parts: An aerosol preparation system (1), wherein the aerosol preparation system (1) can disperse nanoparticles into a gas medium to generate nanoaerosol; A centrifugal container system (2), wherein a surface connection device (4) is provided at the outlet of the centrifugal container system (2), and the surface connection device (4) can be connected to a surface to be sprayed (5); the nano aerosol enters the centrifugal container system (2), is centrifugally rotated in the centrifugal container system (2), and impacts the surface to be sprayed (5) through the surface connection device (4) to form a nano coating; An aerosol transport and processing system (3), the aerosol transport and processing system (3) is connected to both the aerosol preparation system (1) and the centrifugal container system (2), the aerosol transport and processing system (3) processes the charge carried by the particles of the nano aerosol generated by the aerosol preparation system (1), and transports the nano aerosol to the centrifugal container system (2).

2. The nano coating preparation system according to claim 1, Features: The aerosol transport and processing system (3) comprises a transport channel (31) and a static eliminator (32). The static eliminator (32) is arranged on the transport channel (31) and is located downstream of the aerosol preparation system (1). The static eliminator (32) can eliminate the charge carried by the nano aerosol particles.

3. The nano coating preparation system according to claim 2, Features: The aerosol transport processing system (3) further comprises a diffuser charger (33) arranged on the transport channel (31), wherein the diffuser charger (33) is arranged downstream of the static eliminator (32), and the diffuser charger (33) enables the nano aerosol particles to carry the same type of charge.

4. The nano coating preparation system according to claim 3, Features: The diffuser charge device (33) can emit gamma rays or x-rays to process the nano aerosol particles so that their energy is between 2keV and 9.8keV.

5. The nano coating preparation system according to any one of claims 2 to 4, Features: The aerosol transport processing system (3) comprises a carrier gas supply device (34), which is located at the end of the transport channel (31) and can provide a carrier gas with adjustable air pressure into the transport channel (31).

6. The nano coating preparation system according to claim 5, Features: The aerosol preparation system (1) includes an aerosol generator (11), the outlet of the aerosol generator (11) is connected to the delivery channel (31), and the aerosol delivery processing system (3) also includes a dehumidifier (35) arranged on the delivery channel (31), and the dehumidifier (35) is arranged between the carrier gas supply device (34) and the aerosol generator (11).

7. The nano coating preparation system according to claim 1, Features: The centrifugal container system (2) comprises an aerosol centrifugal tank (21), the side wall of which is formed by sequentially connecting a tank body arc section (22), a tank body vertical section (23) and a tank body horizontal section (24), the tank body vertical section (23) and the tank body horizontal section (24) are both tangent to the tank body arc section (22), and the radius R of the tank body arc section (22), the length L of the tank body vertical section (23), and the length D of the tank body horizontal section (24) satisfy: R=L=D.

8. The nano coating preparation system according to claim 7, Features: The surface connection device (4) is arranged on a side of the tank body vertical section (23) close to the tank body horizontal section (24), and the surface connection device (4) comprises elastic material and can be sealed and fitted with the surface to be sprayed (5).

9. The nano coating preparation system according to claim 8, Features: The aerosol centrifugal tank (21) is also provided with a rectifying member (25) for guiding the flow direction of the nano-aerosol, and a vertical flow channel (26) is formed between the outer wall of at least one rectifying member (25) and the inner wall of the tank body vertical section (23), and a horizontal flow channel (27) is formed between the outer wall of at least one rectifying member (25) and the inner wall of the tank body horizontal section (24).

10. The nano coating preparation system according to claim 9, Features: A replaceable guide plate (28) is arranged in the horizontal flow channel (27), and the guide plate (28) can be a porous structure guide plate (28a), a Rafael guide plate (28b) or a streamlined guide plate (28c).

11. The nano coating preparation system according to claim 7, Features: A paddle-type stirrer (29) is arranged in the aerosol centrifugal tank (21). The paddle-type stirrer (29) is made of ceramic, carbon fiber and / or conductive polymer, and the rotation speed of the paddle-type stirrer (29) is adjustable.

12. The nano coating preparation system according to claim 7, Features: The aerosol centrifugal tank (21) is also connected to a vacuum pumping system (6), and the vacuum pumping system (6) comprises an isolation valve (61) and a vacuum pump (62).

13. A method for preparing a nano coating, It is characterized in that A nano coating preparation system according to any one of claims 1 to 12 is used, and comprises the following steps: Nano aerosol preparation step S1, dispersing nanoparticles into a gas medium to prepare nano aerosol; The nanoaerosol treatment step S2 is to eliminate the charge carried by the nanoaerosol particles and make them all carry positive charge or negative charge; In the centrifugal spraying step S3, the nano-aerosol is driven to undergo centrifugal acceleration, so that the nano-aerosol is accelerated and impacts the surface to be sprayed (5) to form a nano-coating.

14. The preparation method according to claim 13, Features: In the centrifugal spraying step S3, the ambient pressure of the nanoaerosol is between 0.4 bar and 0.5 bar before the nanoaerosol is centrifugally accelerated.

15. The preparation method according to claim 13, Features: The nano aerosol particles include metal single substance particles, metal oxide particles and / or non-metal oxide particles with a particle size not greater than 100 nm.

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