A compressed air storage tank with an online sprayed internal anti-corrosion coating and its application method

Abstract

This invention discloses a compressed air storage tank for online spraying of an internal anti-corrosion coating and its usage method, comprising a storage tank and a spraying device; the storage tank is inclined relative to the horizontal plane; one end of the storage tank has an air inlet structure, the other end has an air delivery structure, the top has a pressure relief structure, and the bottom has a condensate storage and drainage structure at a low horizontal position; multiple spraying devices are equidistantly arranged inside the storage tank for cleaning or spraying the anti-corrosion coating on the inner wall of the storage tank; the storage tank also has a temperature and humidity detection mechanism inside. This invention ensures that the inner wall of the storage tank can operate stably for more than ten years without rusting under saturated humidity compressed air conditions, ensuring product safety and service stability.

Description

Technical Field

[0001] This invention relates to pressure vessel technology, and more specifically, to a compressed air storage tank with an online sprayed internal anti-corrosion coating and its usage method. Background Technology

[0002] Compressed air is the most common power gas and the second largest power energy source after electricity, widely used in industrial and mining enterprises, hospitals, and research institutions. In most cases, as long as the relative humidity inside the compressed air container can be kept below 50% under high pressure, only simple chemical corrosion will occur on the inner wall, ensuring long-term stable service even without coating. However, in many cases, it is difficult to guarantee that the medium is absolutely dry. If the relative humidity cannot be kept below 50%, the introduction of water vapor will form a continuous water film on the container wall, altering the reaction mechanism and leading to electrochemical corrosion under thin liquid film conditions. This greatly accelerates the corrosion process, causing rapid material corrosion failure and affecting equipment lifespan.

[0003] For conventional compressed air containers, the compressed air inside is typically maintained at a constant pressure, with very small amounts entering or exiting. Under constant pressure, supersaturated water in the air will condense and precipitate as the temperature decreases. By promptly removing this condensate before it evaporates back into the air due to increased temperature, continuous drying of the compressed air can be achieved, effectively preventing the continuous precipitation of condensate. Drying the small amount of compressed air entering the system using drying technology can easily achieve the desired drying, ensuring that the internal relative humidity remains within a safe range below 50%. Therefore, the inner walls of conventional compressed air storage and transportation equipment are usually not treated with anti-corrosion measures and are recommended to be used untreated.

[0004] However, in some fields, it is impossible to dehumidify compressed air. For example, in the increasingly widespread field of compressed air energy storage.

[0005] Compressed air energy storage (CAES) technology uses air compressor units to store excess electrical energy during off-peak hours as the pressure potential energy of compressed air in storage tanks. When electricity demand increases, the stored compressed air is released, heated, and then converted into electrical energy by a turbine to meet peak electricity demand. Because compressed air is a low-energy-density medium, meeting the power storage requirements necessitates large storage spaces capable of providing hundreds of thousands of cubic meters of space and withstanding pressures exceeding 10 MPa. Furthermore, daily storage and venting operations are required, making effective dehumidification of the internal compressed air difficult. Due to resource and distribution constraints, high-quality natural caverns, artificial salt caverns, and artificial mines—resources for ultra-large compressed air storage—are becoming increasingly scarce, highlighting the advantages and demand for steel-built surface storage tanks. However, without ensuring effective drying, internal wall corrosion becomes a key technical bottleneck hindering this application.

[0006] Coatings are the preferred solution to this problem. However, under high pressure, conventional coatings are prone to interfacial stress due to the inconsistency in deformation between the metal material and the coating under stress, leading to coating cracking or peeling; or the cold wall effect caused by the temperature gradient of the tank wall, causing coating bulging and peeling. Especially under frequent pressure and temperature fluctuations, coating failure is further aggravated, leading to cracking, bulging, and even large-area peeling. Special coatings that can be used in the above-mentioned high-pressure environments often require coatings with excellent density, excellent ductility, and excellent adhesion to steel materials. These coatings are expensive and difficult to apply on a large scale.

[0007] Oil and wax films exhibit excellent ductility under high pressure, effectively avoiding the aforementioned problems and showing promising application prospects under these conditions. However, oil and wax films can undergo emulsification and other reactions under long-term rinsing and immersion in condensate, leading to performance degradation and making it difficult to meet the long-term service requirements of equipment (15 to 20 years or more). Stopping the system for recoating after significant performance degradation would obviously have a major impact on the continuous operation of the equipment and would be extremely costly. If online recoating of the internal anti-corrosion coating could be achieved, substantial costs could be saved, promoting the widespread application of ground-mounted compressed air storage tanks.

[0008] Although Chinese patent 201780010667.1 claims a method for covering the inner wall of a cavity with a protective layer made of anti-corrosion wax, this cavity is used for the vehicle body and additional components for the vehicle body, and the cavity volume of the vehicle body is relatively small, usually with a maximum space of no more than 1m³. 3The cavity is typically not pressurized, with internal pressure at normal atmospheric pressure, and the inner wall environment is usually relatively dry, without water vapor. This technology is difficult to fully apply to the inner walls of ultra-large, ultra-high-pressure compressed air storage tanks used for energy storage, which have a volume of hundreds of thousands of cubic meters, internal pressures often exceeding 10 MPa, and relative humidity consistently at 100%. Furthermore, this technology makes it impossible to achieve online coating and touch-up application of paint to the inner walls of such containers. Summary of the Invention

[0009] To address the aforementioned deficiencies in the existing technology, the purpose of this invention is to provide a compressed air storage tank with an online sprayed internal anti-corrosion coating and its usage method, ensuring that the inner wall of the storage tank can operate stably for more than ten years under saturated humidity compressed air conditions without rusting, thus ensuring the safety and service stability of the product.

[0010] To achieve the above objectives, the present invention adopts the following technical solution:

[0011] On the one hand, a compressed air storage tank for online spraying of an internal anti-corrosion coating includes a storage tank and a spraying device;

[0012] The storage tank is inclined relative to the horizontal plane;

[0013] The storage tank is equipped with an air inlet structure at one end, an air delivery structure at the other end, a pressure relief structure at the top, and a condensate storage and discharge structure at the bottom low level.

[0014] The spraying device has multiple units, which are equidistantly arranged inside the storage tank, and is used to clean the inner wall of the storage tank or spray an anti-corrosion coating.

[0015] The storage tank is also equipped with a temperature and humidity detection device.

[0016] Preferably, the storage tank is mounted on a shock-absorbing device via a support.

[0017] Preferably, the air intake structure includes an air intake pipe connected to the inside of the storage tank and a heating dehumidifier and an air intake valve installed on the air intake pipe.

[0018] Preferably, the gas transmission structure includes a gas transmission pipeline connected to the interior of the storage tank and a first gas transmission valve and a second gas transmission valve disposed on the gas transmission pipeline.

[0019] Preferably, the pressure relief structure includes a pressure relief pipe connected to the inside of the storage tank and a pressure gauge and a pressure relief valve installed on the pressure relief pipe.

[0020] Preferably, the condensate storage and drainage structure includes a condensate storage and drainage container connected to the inside of the storage tank, and an inlet valve and a drain valve provided on the condensate storage and drainage container.

[0021] Preferably, the temperature and humidity detection mechanism includes a humidity sensor and a temperature sensor located on the top side inside the storage tank.

[0022] Preferably, the anti-corrosion coating is a wax coating or an oil film coating;

[0023] The thickness of the wax coating is 20 to 200 μm, which is three times or more the roughness of the inner wall of the storage tank.

[0024] The thickness of the oil film coating is 20 to 500 μm, which is five times or more the roughness of the inner wall of the storage tank.

[0025] The anti-corrosion coating does not crack or peel under 10MPa high pressure and pressure fluctuations.

[0026] On the other hand, a method of using a compressed air storage tank with an online sprayed internal anti-corrosion coating includes the following steps:

[0027] S1. Dry the inside of the storage tank;

[0028] S2. Apply the anti-corrosion coating to the inner wall of the storage tank using the spraying device;

[0029] S3. Allow the anti-corrosion coating to cure and form a film.

[0030] S4. Check whether the anti-corrosion coating is evenly applied and measure whether the average thickness of the anti-corrosion coating meets the requirements. If it does not meet the requirements, repeat steps S1 to S4.

[0031] Preferably, step S1 specifically includes: opening the air inlet valve and the water inlet valve, closing the drain valve and the second air supply valve, introducing compressed air into the storage tank through the air inlet pipe to evaporate the surface water vapor inside the storage tank, opening the drain valve and the second air supply valve, and carrying away the water vapor with the compressed air. When the humidity sensor detects that the relative humidity inside the storage tank is below 50%, the air inlet valve and the drain valve are closed.

[0032] Step S2 specifically includes: opening the air inlet valve to introduce compressed air into the storage tank, opening the spray device to deliver paint droplets of wax film or oil film to the inner wall of the storage tank in the form of spray, and using the compressed air to carry the paint droplets into the inner wall of the storage tank and distribute them evenly.

[0033] Step S3 specifically includes: when the gas pipeline detects that the compressed air contains the coating droplets, closing the air inlet valve, the gas pipeline, the drain valve and the second gas valve, and letting it stand until the anti-corrosion coating cures into a film;

[0034] Step S4 specifically includes: during coating, opening the water inlet valve and closing the drain valve to connect the condensate storage and drainage container with the storage tank; after coating is completed, closing the water inlet valve and opening the drain valve to inspect the coating condition within the condensate storage and drainage structure.

[0035] Preferably, the process also includes inspection and online recoating steps during the service life of the storage tank, the specific steps of which are as follows:

[0036] Step A: Check and close the water inlet valve, open the gas supply pipe and the drain valve, drain the condensate accumulated in the condensate storage container, and determine whether online touch-up coating is needed based on the condensate condition. If touch-up coating is needed, proceed to Step B.

[0037] Step B: Cleaning. Close the first air supply valve and the drain valve. Open the spray device and the water inlet valve near the area to be recoated. Spray clean water onto the area to be recoated for rinsing. After the condensate storage container is full of water, close the drain valve and then open the drain valve to check if there is rust or other impurities in the drained water. If there are, continue with Step B until there is no visible rust or other impurities in the water. Then, perform the recoating according to Steps S1 to S4.

[0038] The compressed air storage tank with an online sprayed internal anti-corrosion coating and its usage method provided by the present invention have the following beneficial effects:

[0039] 1) Compared with conventional compressed air pressure storage tanks, the present invention can effectively avoid internal wall corrosion without the need for frequent dehumidification during service, thus significantly extending the service life of the equipment;

[0040] 2) Compared with traditional pipeline coatings, the coating proposed in this invention has unique advantages in terms of high-pressure liquid film corrosion. The wax coating has strong hydrophobicity and water resistance, effectively preventing water from wetting and continuously forming a film on the steel surface, thus effectively preventing corrosion caused by compressed air and its condensate film. The wax coating has extremely strong flexibility and self-healing properties. On the one hand, it avoids the cracking and damage that conventional coatings are prone to in high-pressure and drastically fluctuating environments, and the coating surface is less prone to cracking. On the other hand, scratches caused by particle friction can also be automatically repaired. Furthermore, wax coatings have a lower unit price, lower density, and larger coverage area per unit mass compared to conventional coatings, saving significant coating costs. Simultaneously, this wax coating has good corrosion resistance, ensuring that the protected steel material does not show significant rust after 1500 hours of salt spray testing, and can protect containers from severe internal wall corrosion for more than 20 years of service.

[0041] 3) Compared to traditional wax-coated inner cavities, this invention can withstand higher pressures and has a larger volume, meeting the high-pressure compressed air storage requirements for energy storage. Furthermore, this invention allows for online recoating after the inner wall coating fails, significantly extending the safe service life of the inner wall and improving equipment safety. Attached Figure Description

[0042] Figure 1 This is a schematic diagram of the compressed air storage tank of the present invention. Detailed Implementation

[0043] To better understand the above-mentioned technical solutions of the present invention, the technical solutions of the present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0044] Combination Figure 1 As shown, the compressed air storage tank for online spraying of internal anti-corrosion coating provided by the present invention includes a storage tank 1 and a spraying device 2.

[0045] Storage tank 1 can be a horizontal storage tank, a vertical storage tank, or a spherical tank, etc. Compressed air storage tanks. In this embodiment, a horizontal storage tank is used, which is mainly composed of UOE pipelines connected by welding. It is supported by a bracket 3 connected to a shock-absorbing device and tilted at a certain slight angle to the horizontal plane. The inner wall of storage tank 1 is guaranteed to have a certain slope to avoid being completely horizontal, so as to facilitate the accumulation of internal condensate.

[0046] Multiple spraying devices 2 are equidistantly arranged inside the storage tank 1. Each spraying device 2 has at least two delivery paths: one path can atomize and spray wax or oil film coatings, and the other path can spray cleaning water. The coatings or cleaning water can be atomized and sprayed onto the inner wall of the storage tank 1 to clean the inner wall of the storage tank 1 or to spray an anti-corrosion coating 4. The number and spacing of the spraying devices 2 should be such that the inner wall of the storage tank 1 is evenly and effectively covered by the coating.

[0047] The anti-corrosion coating 4 is a wax coating or an oil film coating, which can effectively isolate water and prevent corrosion of the inner wall of the storage tank 1.

[0048] The thickness of the wax coating is 20 to 200 μm, which is determined by the surface roughness of the inner wall of the storage tank 1. It is three times or more than three times the roughness of the inner wall of the storage tank 1 to ensure the formation of a continuous coating shield of a certain thickness.

[0049] The thickness of the oil film coating is 20 to 500 μm, which is determined by the surface roughness of the inner wall of the storage tank 1. It is five times or more than five times the roughness of the inner wall of the storage tank 1 to ensure the formation of a continuous coating shield of a certain thickness.

[0050] A condensate storage and drainage structure is installed at the lowest horizontal position of the bottom of storage tank 1 to store condensate inside the tank. This structure includes a condensate storage and drainage container 5 connected to the inside of storage tank 1, an inlet valve 6 at the upper end of the container 5, and a drain valve 7 at the lower end. Normally, the inlet valve 6 is open, and the drain valve 7 is closed. When the condensate in storage tank 1 reaches a certain level and needs to be drained, the inlet valve 6 is closed first, then the drain valve 7 is opened to drain the condensate from the container 5. After this process, the drain valve 7 is closed, and the inlet valve 6 is opened again to restore the condensate storage and drainage system.

[0051] The condensate storage and drainage container 5 adopts a corrosion-resistant design, with a surface coating that provides better waterproofing or made of corrosion-resistant materials such as stainless steel.

[0052] The storage tank 1 has an air inlet structure at one end and an air delivery structure at the other end. The air inlet structure includes an air inlet pipe 8 connected to the inside of the storage tank 1, and a heating dehumidifier 9 and an air inlet valve 10 installed on the air inlet pipe 8. The air delivery structure includes an air delivery pipe 11 connected to the inside of the storage tank 1, and a first air delivery valve 12 and a second air delivery valve 13 installed on the air delivery pipe 11. Closing the second air delivery valve 13 (air delivery pipe 11 closed) and opening the air inlet valve 10 (air inlet pipe 8 open) allows compressed air to be delivered into the storage tank 1. Closing the air inlet valve 10 (air inlet pipe 8 closed) and opening the second air delivery valve 13 (air delivery pipe 11 open) allows compressed air to be delivered outwards.

[0053] The heating dehumidifier 9 can control the humidity and moisture content of the compressed air entering the storage tank 1, and can control the dew point of the compressed air below the ambient temperature, or heat the compressed air.

[0054] The storage tank 1 is also equipped with a humidity sensor 14 and a temperature sensor 15. The humidity sensor 14 can monitor the relative humidity of the compressed air in the storage tank 1 in real time, and the temperature sensor 15 can monitor the temperature of the compressed air in the storage tank 1 in real time.

[0055] The top of the storage tank 1 is equipped with a pressure relief structure, which includes a pressure relief pipe 16 connected to the inside of the storage tank 1, and a pressure gauge 17 and a pressure relief valve 18 installed on the pressure relief pipe 16. The pressure gauge 17 monitors the pressure of compressed air in real time. When overpressure occurs, the pressure relief valve 18 automatically opens to ensure safety, and closes after the pressure reaches the safe value.

[0056] The present invention also provides a method for using a compressed air storage tank with an online sprayed internal anti-corrosion coating based on the present invention, comprising the following steps:

[0057] S1. Dry the inside of storage tank 1; open air inlet valve 8 and water inlet valve 6, close drain valve 7 and second air supply valve 13, and introduce high-temperature (recommended temperature above 90℃) dry compressed air into storage tank 1 through air inlet pipe 8 to evaporate the surface water vapor inside storage tank 1. Then open drain valve 7 and second air supply valve 13 to carry away excess water vapor through compressed air. When humidity sensor 14 detects that the relative humidity inside the storage tank is below 50%, close air inlet valve 10 and drain valve 7.

[0058] S2. Apply anti-corrosion coating 4 to the inner wall of storage tank 1 through spray device 2; open air inlet valve 10 to introduce high temperature (below the upper limit of the safe use temperature of coating) dry compressed air into storage tank 1, open spray device 2 to deliver coating droplets of wax film or oil film to the inner wall of storage tank 1 in the form of spray, and use compressed air to carry the coating droplets into the inner wall of storage tank 1 and distribute them evenly.

[0059] S3. Let the anti-corrosion coating 4 cure and form a film. When the gas pipeline 11 detects that the compressed air contains paint droplets, close the inlet valve 10, the gas pipeline 11, the drain valve 7, and the second gas valve 13, and let it stand for a sufficient time to allow the anti-corrosion coating 4 to cure and form a film.

[0060] S4. Close the gas pipeline 11, water inlet valve 6 and first gas valve 12, then open the drain valve 6 and second gas valve 13. Check whether the anti-corrosion coating 4 is evenly covered and measure whether the average thickness of the anti-corrosion coating 4 meets the requirements. If it does not meet the requirements, repeat steps S1 to S4.

[0061] The method of use of this invention also includes inspection and online recoating steps during the service of the storage tank, the specific steps of which are as follows:

[0062] Step A: Check and close the water inlet valve 6, open the gas supply pipe 11 and the drain valve 7, drain the condensate accumulated in the condensate storage container 5, and determine whether online touch-up coating is needed based on the condition of the condensate (e.g., there is a lot of rust in the condensate). If touch-up coating is needed, proceed to Step B.

[0063] Step B: Cleaning. Close the first air supply valve 12 and the drain valve 7. Open the spray device 2 and the water inlet valve 6 near the area to be recoated. Spray clean water onto the area to be recoated for rinsing. After the storage tank 1 is full of water, close the drain valve 7 and then open the drain valve 7. Check if there is rust or other impurities in the drained water. If there are, continue with Step B until there is no visible rust or other impurities in the water. Then, perform the recoating according to Steps S1 to S4.

[0064] The dew point of the compressed air is controlled at 20°C below the ambient temperature. For example, if the current temperature inside storage tank 1 is 0°C, the dew point is controlled at -20°C or lower.

[0065] The temperature of the compressed air introduced must be lower than the dropping point temperature of the inner wall wax film coating or the upper limit of the safe operating temperature of the oil film coating. Preferably, the temperature of the compressed air introduced must be 5°C lower than the dropping point temperature of the inner wall wax film coating or the upper limit of the safe operating temperature of the oil film coating. For example, if the dropping point temperature of the wax film is 100°C, then the temperature of the compressed air introduced should not be higher than 95°C.

[0066] This invention relates to a compressed air storage tank with an online spray coating for internal anti-corrosion and its usage method. The tank has a special coating on its inner wall surface, which prevents condensation from forming a continuous water film on the surface. Even under high pressure of 10MPa and pressure fluctuations, the coating can still ensure that it does not crack or peel off. The storage tank is equipped with an online spraying device, which can use compressed air to spray the coating on the inner wall of the storage tank online. It can also be used for touch-up coating after the coating has failed due to long-term service. Therefore, it can ensure that the material can be stably used for more than ten years under saturated humidity compressed air conditions without rusting, ensuring the safety and service stability of the product.

[0067] Those skilled in the art should recognize that the above embodiments are merely illustrative of the present invention and are not intended to limit the present invention. Any variations or modifications to the above embodiments that are within the spirit and essence of the present invention will fall within the scope of the claims of the present invention.

Claims

1. A compressed air storage tank with an online sprayed internal anti-corrosion coating, characterized in that: Includes storage tanks and spraying equipment; The storage tank is inclined relative to the horizontal plane; The storage tank is equipped with an air inlet structure at one end, an air delivery structure at the other end, a pressure relief structure at the top, and a condensate storage and discharge structure at the bottom low level. The spraying device has multiple units, which are equidistantly arranged inside the storage tank, and is used to clean the inner wall of the storage tank or spray an anti-corrosion coating. The storage tank is also equipped with a temperature and humidity detection device. The method of using the compressed air storage tank with the online spraying of the internal anti-corrosion coating includes the following steps: S1. Dry the inside of the storage tank; S2. Apply the anti-corrosion coating to the inner wall of the storage tank using the spraying device; S3. Allow the anti-corrosion coating to cure and form a film. S4. Check whether the anti-corrosion coating is evenly covered and measure whether the average thickness of the anti-corrosion coating meets the requirements. If it does not meet the requirements, repeat steps S1 to S4. It also includes inspection and online recoating steps during the service life of the storage tank, the specific steps of which are as follows: Step A: Check and close the inlet valve of the condensate storage and drainage structure of the storage tank, open the gas transmission pipeline of the gas transmission structure and the drain valve of the condensate storage and drainage structure, drain the condensate accumulated in the condensate storage and drainage container of the condensate storage and drainage structure, and determine whether online touch-up coating is needed based on the condensate condition. If touch-up coating is needed, proceed to Step B. Step B: Cleaning. Close the first gas supply valve and the drain valve of the gas supply structure of the storage tank. Open the spray device and the water inlet valve near the area to be coated. Spray clean water onto the area to be coated for rinsing. After the condensate storage container is full of water, close the drain valve and then open the drain valve to check whether there is rust or other impurities in the drained water. If there are, continue with Step B until there is no visible rust or other impurities in the water. Then, perform the coating according to Steps S1 to S4.

2. The compressed air storage tank with an online sprayed internal anti-corrosion coating according to claim 1, characterized in that: The storage tank is mounted on a shock-absorbing device via a support frame.

3. The compressed air storage tank with an online sprayed internal anti-corrosion coating according to claim 1, characterized in that: The air intake structure includes an air intake pipe connected to the inside of the storage tank, and a heating dehumidifier and an air intake valve installed on the air intake pipe.

4. The compressed air storage tank with an online sprayed internal anti-corrosion coating according to claim 1, characterized in that: The gas transmission structure includes a gas transmission pipeline connected to the inside of the storage tank, and a first gas transmission valve and a second gas transmission valve installed on the gas transmission pipeline.

5. The compressed air storage tank with an online sprayed internal anti-corrosion coating according to claim 1, characterized in that: The pressure relief structure includes a pressure relief pipe connected to the inside of the storage tank, and a pressure gauge and a pressure relief valve installed on the pressure relief pipe.

6. The compressed air storage tank with an online sprayed internal anti-corrosion coating according to claim 1, characterized in that: The condensate storage and drainage structure includes a condensate storage and drainage container connected to the inside of the storage tank, and an inlet valve and a drain valve provided on the condensate storage and drainage container.

7. The compressed air storage tank with an online sprayed internal anti-corrosion coating according to claim 1, characterized in that: The temperature and humidity detection mechanism includes a humidity sensor and a temperature sensor located on the top side inside the storage tank.

8. The compressed air storage tank with an online sprayed internal anti-corrosion coating according to claim 1, characterized in that: The anti-corrosion coating is a wax coating or an oil film coating; The thickness of the wax coating is 20 to 200 μm, which is three times or more the roughness of the inner wall of the storage tank. The thickness of the oil film coating is 20 to 500 μm, which is five times or more the roughness of the inner wall of the storage tank. The anti-corrosion coating does not crack or peel under 10MPa high pressure and pressure fluctuations.

9. A method of using a compressed air storage tank with an online sprayed internal anti-corrosion coating as described in any one of claims 1-8, characterized in that, Includes the following steps: S1. Dry the inside of the storage tank; S2. Apply the anti-corrosion coating to the inner wall of the storage tank using the spraying device; S3. Allow the anti-corrosion coating to cure and form a film. S4. Check whether the anti-corrosion coating is evenly applied and measure whether the average thickness of the anti-corrosion coating meets the requirements. If it does not meet the requirements, repeat steps S1 to S4.

10. The method of use according to claim 9, characterized in that, Step S1 specifically includes: opening the air inlet valve of the air inlet structure of the storage tank and the water inlet valve of the condensate storage and drainage structure of the storage tank; closing the drain valve of the condensate storage and drainage structure and the second air supply valve of the air supply structure of the storage tank; introducing compressed air into the storage tank through the air inlet pipe of the air inlet structure to evaporate the surface water vapor inside the storage tank; opening the drain valve and the second air supply valve to carry away the water vapor through the compressed air; and closing the air inlet valve and the drain valve after the humidity sensor of the temperature and humidity detection mechanism detects that the relative humidity inside the storage tank is below 50%. Step S2 specifically includes: opening the air inlet valve to introduce compressed air into the storage tank, opening the spray device to deliver paint droplets of wax film or oil film to the inner wall of the storage tank in the form of spray, and using the compressed air to carry the paint droplets into the inner wall of the storage tank and distribute them evenly. Step S3 specifically includes: when the gas transmission pipeline of the gas transmission structure detects that the compressed air contains the coating droplets, closing the air inlet valve, the gas transmission pipeline, the drain valve and the second gas transmission valve, and letting it stand until the anti-corrosion coating cures into a film; Step S4 specifically includes: during coating, opening the water inlet valve and closing the drain valve to connect the condensate storage and drainage container with the storage tank; after coating is completed, closing the water inlet valve and opening the drain valve to inspect the coating condition within the condensate storage and drainage structure.

11. The method of use according to claim 9, characterized in that, It also includes inspection and online recoating steps during the service life of the storage tank, the specific steps of which are as follows: Step A: Check and close the water inlet valve, open the gas supply pipe and the drain valve, drain the condensate accumulated in the condensate storage container, and determine whether online touch-up coating is needed based on the condensate condition. If touch-up coating is needed, proceed to Step B. Step B: Cleaning. Close the first air supply valve and the drain valve. Open the spray device and the water inlet valve near the area to be recoated. Spray clean water onto the area to be recoated for rinsing. After the condensate storage container is full of water, close the drain valve and then open the drain valve to check if there is rust or other impurities in the drained water. If there are, continue with Step B until there is no visible rust or other impurities in the water. Then, perform the recoating according to Steps S1 to S4.

Images