Filter exhaust structure for an airport fuel farm

Abstract

The application provides a filter exhaust structure for an airport oil depot, which comprises a filter, a pressure discharge pipe and a pressure relief valve, the pressure discharge pipe is fixedly installed at the bottom of the filter, and the pressure relief valve is fixedly installed on the outer surface of the pressure discharge pipe; an exhaust valve, a first exhaust pipe, an eccentric impeller sight mirror, a first three-way T-shaped ball valve and a second three-way T-shaped ball valve connected in series with the first three-way T-shaped ball valve are sequentially connected above the pressure discharge pipe. In use, different opening modes of the first three-way T-shaped ball valve and the second three-way T-shaped ball valve can be used for different situations, the combination mode of the two groups of three-way ball valves is used to realize the switching of the air inlet pipeline and the exhaust pipeline, the mode is simple, time-saving and labor-saving, and the diversity of the exhaust structure is also increased.

Description

Technical Field

[0001] This invention relates to the field of exhaust filtration technology, and more particularly to an exhaust filtration structure for use in airport oil depots. Background Technology

[0002] Because aviation kerosene is widely used as fuel for civil aircraft, the industry has very strict requirements for its quality. When handling operations such as receiving, dispensing, and transferring aviation kerosene stored in airport oil depots, it is necessary to filter it through multiple stages of filters to ensure its quality. At the same time, the pressure inside the filters is as high as 0.8 MPa.

[0003] Existing oil-blocking and venting valves often become stuck between the oil-blocking float and the venting valve's venting port sealing surface due to impurities inside the oil, leading to internal leakage of the venting valve and a continuous flow of oil into the underground tank, potentially causing a tank overflow accident. Furthermore, the existing filter venting and inlet pipes share the same pipeline. When depressurizing or cleaning the filter, bottom oil drainage is required, which necessitates air intake for smooth oil drainage. However, to achieve a closed-loop oil and gas discharge, the venting pipe's outlet is below the liquid level in the underground tank. Additionally, the venting pipe often has a long path with many bends, and oil often accumulates at the bends. Therefore, when air intake is needed, it is often impossible to intake air, and oil backflow may even occur. Summary of the Invention

[0004] This invention provides a filter exhaust structure for airport oil depots. This invention enables the switching between intake and exhaust pipelines in a simple, time-saving, and labor-saving manner. It also increases the versatility of the exhaust structure, improves oil blocking function, enhances the practicality of the pipeline, and can be used in outdoor environments. It can prevent problems such as oil backflow and allows for observation of whether the exhaust valve has internal leakage and the amount of internal leakage.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: a filter exhaust structure for airport oil depots, comprising:

[0006] Filter;

[0007] A pressure relief pipe is fixedly installed at the bottom of the filter, and a pressure relief valve is fixedly installed at the center of the outer surface of the pressure relief pipe;

[0008] The first connecting pipe is fixedly installed at the center of the top of the pressure relief pipe, and an exhaust valve is fixedly installed on the top of the first connecting pipe;

[0009] An oil-blocking float is movably connected to the inner wall at the bottom of the exhaust valve;

[0010] First exhaust pipe;

[0011] An eccentric impeller sight glass is fixedly installed at one end of the first exhaust pipe, and a second connecting pipe is fixedly connected to the other end of the eccentric impeller sight glass.

[0012] The first three-way T-type ball valve is fixedly installed at the other end of the second connecting pipe;

[0013] The main ball valve is fixedly installed on the top of the first exhaust pipe.

[0014] Preferably, the inner walls of the top and bottom of the exhaust valve are provided with exhaust ports that match the oil-blocking float.

[0015] Preferably, a second three-way T-ball valve is fixedly installed on the right side of the first three-way T-ball valve, a second exhaust pipe is fixedly connected to the right side of the second three-way T-ball valve, the other end of the second exhaust pipe is fixedly connected to a buried tank, and an oil outlet pipe is fixedly connected to the top of the buried tank.

[0016] Preferably, a branch pipe is fixedly installed at the bottom of the second three-way T-ball valve, and the other end of the branch pipe is fixedly connected to the center of the bottom of the second exhaust pipe.

[0017] Preferably, a filter tube is fixedly embedded in the inner wall of the second three-way T-ball valve near the right side, a stainless steel sintered mesh is fixedly embedded in the inner wall of the filter tube, an oil-blocking and breathable membrane is fixedly connected to the right side of the stainless steel sintered mesh, and a stainless steel mesh is fixedly connected to the right side of the oil-blocking and breathable membrane.

[0018] Preferably, a two-way ball valve is fixedly connected to the top of the second three-way T-type ball valve, an air inlet pipe is fixedly connected to the top of the two-way ball valve, a waterproof venting membrane is fixedly connected to the top of the air inlet pipe, and a waterproof air inlet cap is threadedly connected to the inner wall of the waterproof venting membrane near the top.

[0019] Preferably, a protective cover is fixedly connected to the top of the waterproof air inlet cap, and a breathable membrane is fixedly connected to the inner wall of the protective cover.

[0020] Preferably, a silicone ring is fixedly fitted on the outer surface of the protective cover near the bottom, and ventilation holes are opened on both sides of the protective cover near the top. The material of the breathable film is polytetrafluoroethylene.

[0021] Preferably, the filter has oil outlets at both the top and bottom.

[0022] Compared with the prior art, the advantages and positive effects of the present invention are as follows:

[0023] 1. This invention controls the opening methods of the first three-way T-type ball valve and the second three-way T-type ball valve, which can be used in different situations. The combination of two sets of three-way ball valves can be used to switch between the intake and exhaust pipelines. The method is simple, time-saving and labor-saving, and also increases the versatility of the exhaust structure.

[0024] 2. During the exhaust process, the stainless steel mesh can first filter out large particles of impurities, thus protecting the oil-blocking and breathable membrane. The oil-blocking and breathable membrane is a microporous membrane made of polytetrafluoroethylene through calendering, extrusion, and biaxial stretching. It features high air permeability, uniform pore size distribution, and resistance to damage. After being treated with a superoleophobic coating, it can achieve oil-blocking and breathable functions, separating oil and gas. The sintered stainless steel mesh is made of multiple layers of stainless steel wire mesh through special lamination and vacuum sintering. It features high mechanical strength and high filtration accuracy. It is mainly used to supplement the oil-blocking and breathable function of the oil-blocking and breathable membrane and increase the mechanical strength of the entire oil-blocking and breathable structure. The stainless steel mesh, oil-blocking and breathable membrane, and sintered stainless steel mesh are combined together through the filter tube to form an oil-blocking and breathable structure, increasing the mechanical strength of the entire filter screen, thereby improving the oil-blocking function and its practical performance.

[0025] 3. This invention adds a separate air intake pipe and a two-way ball valve to the air intake pipe, including an air intake cap and a waterproof ventilated membrane. This prevents particulate matter and liquid in the atmosphere from entering the pipe through the air intake cap. The protective cover protects the ventilated membrane and prevents it from being damaged, thus affecting its function. This achieves the functions of waterproofing, dustproofing, and preventing contamination of oil quality. Therefore, this structure can be used in outdoor environments and can prevent problems such as oil backflow.

[0026] 4. The present invention adds an eccentric impeller sight glass between the exhaust valve and the first three-way T-type ball valve, which can simultaneously observe the exhaust and intake effects. It can increase the cross-sectional area of ​​the exhaust pipe, increase the buffer by eccentricity, reduce the impact on the oil-blocking exhaust film, and also enable the observation of whether the exhaust valve has internal leakage and the amount of internal leakage. Attached Figure Description

[0027] Figure 1 This invention provides a three-dimensional structural diagram of a filter exhaust structure for an airport oil depot.

[0028] Figure 2 This invention provides a partial three-dimensional structural diagram of a filter exhaust structure for an airport oil depot.

[0029] Figure 3 This invention provides a three-dimensional structural diagram of a filter exhaust structure for an airport oil depot.

[0030] Figure 4This invention provides a partial cross-sectional perspective view of a filter exhaust structure for an airport oil depot.

[0031] Figure 5 This invention provides a partial three-dimensional structural diagram of a filter exhaust structure for an airport oil depot.

[0032] Figure 6 This invention provides a partial cross-sectional perspective view of a filter exhaust structure for an airport oil depot.

[0033] Figure 7 This invention provides a partial cross-sectional perspective view of a filter exhaust structure for an airport oil depot.

[0034] Figure 8 This invention provides a partial cross-sectional perspective view of a filter exhaust structure for an airport oil depot.

[0035] Figure 9 This invention provides a schematic diagram of a filter exhaust structure for an airport oil depot;

[0036] Figure 10 This invention proposes a filter exhaust structure for airport oil depots. Figure 1 A magnified three-dimensional structural diagram of A in the diagram.

[0037] Legend: 1. Filter; 2. Pressure relief pipe; 201. Pressure relief valve; 202. First connecting pipe; 203. Exhaust valve; 204. First exhaust pipe; 205. Eccentric impeller sight glass; 206. Second connecting pipe; 207. Oil-blocking float; 208. First three-way T-ball valve; 209. Main ball valve; 3. Second three-way T-ball valve; 301. Branch pipe; 302. Second exhaust pipe; 303. Underground tank; 304. Oil outlet pipe; 305. Filter pipe; 306. Stainless steel mesh; 307. Oil-blocking and breathable membrane; 308. Stainless steel sintered mesh; 4. Two-way ball valve; 401. Air inlet pipe; 402. Waterproof and breathable membrane; 403. Waterproof air inlet cap; 404. Protective cover; 405. Vent hole; 406. Silicone ring; 407. Breathable membrane. Detailed Implementation

[0038] To better understand the above-mentioned objectives, features, and advantages of the present invention, the present invention will be further described below in conjunction with the accompanying drawings and embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0039] Numerous specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways than those described herein, and therefore the invention is not limited to the specific embodiments disclosed in the following specification.

[0040] Example 1, as Figure 1-10 As shown, the present invention provides a filter exhaust structure for an airport oil depot, comprising:

[0041] Filter 1;

[0042] The pressure relief pipe 2 is fixedly installed at the bottom of the filter 1, and a pressure relief valve 201 is fixedly installed at the center of the outer surface of the pressure relief pipe 2. By opening the pressure relief valve 201 on the pressure relief pipe 2, the pressure of the filter 1 can be relieved. The pressure inside the filter 1 is as high as 0.8 MPa.

[0043] The first connecting pipe 202 is fixedly installed at the center of the top of the pressure relief pipe 2, and an exhaust valve 203 is fixedly installed on the top of the first connecting pipe 202. When there is gas inside the filter 1, the gas enters the exhaust valve 203 through the through hole at the bottom of the exhaust valve 203. At this time, under the action of the gas, the oil-blocking float 207 floats up, opens the switch of the exhaust valve 203, and allows the exhaust valve 203 to exhaust gas, thereby allowing the gas to pass through the exhaust valve 203.

[0044] The oil-blocking float 207 is movably connected to the inner wall at the bottom of the exhaust valve 203. When there is gas in the filter 1, the gas rises to the top of the exhaust valve 203 and is discharged through the exhaust pipe of the exhaust valve 203. When the gas is exhausted, the oil in the filter 1 fills the exhaust valve 203, pushing the oil-blocking float 207 in the exhaust valve 203 to the exhaust port and sealing it, thus realizing the oil blocking and exhaust function.

[0045] First exhaust pipe 204;

[0046] An eccentric impeller sight glass 205 is fixedly installed at one end of the first exhaust pipe 204, and the other end of the eccentric impeller sight glass 205 is fixedly connected to a second connecting pipe 206. The eccentric impeller sight glass 205 can simultaneously observe the exhaust and intake effects, and can increase the cross-sectional area of ​​the pipe, increase the buffer by eccentricity, reduce the sudden increase in pressure such as water hammer, reduce the impact on the oil-blocking and breathable membrane 307, and can also observe whether the exhaust valve 203 has internal leakage and how much internal leakage there is.

[0047] The first three-way T-type ball valve 208 is fixedly installed at the other end of the second connecting pipe 206. The three-way ball valve can rotate 360 ​​degrees. By rotating the first three-way T-type ball valve 208, the exhaust structure can achieve different effects.

[0048] The main ball valve 209 is fixedly installed on the top of the first exhaust pipe 204. The main ball valve 209 can be used for maintenance of accessories such as the eccentric impeller sight glass 205 behind the exhaust valve 203.

[0049] Furthermore, such as Figure 1-10 As shown, the inner walls of the top and bottom of the exhaust valve 203 are provided with exhaust ports that match the oil-blocking float 207, and the oil-blocking float 207 inside the exhaust valve 203 can reach the exhaust port.

[0050] Furthermore, such as Figure 1-10 As shown, a second three-way T-type ball valve 3 is fixedly installed on the right side of the first three-way T-type ball valve 208. A second exhaust pipe 302 is fixedly connected to the right side of the second three-way T-type ball valve 3. The other end of the second exhaust pipe 302 is fixedly connected to the underground tank 303. An oil outlet pipe 304 is fixedly connected to the top of the underground tank 303. The underground tank 303 is buried underground and can be connected to an external oil suction pipe through the oil outlet pipe 304.

[0051] Furthermore, such as Figure 1-10 As shown, a branch pipe 301 is fixedly installed at the bottom of the second three-way T-ball valve 3. The other end of the branch pipe 301 is fixedly connected to the center of the bottom of the second exhaust pipe 302. By controlling the different opening modes of the first three-way T-ball valve 208 and the second three-way T-ball valve 3, it can be used for different situations. When the left and right sides of the first three-way T-ball valve 208 are open and the top is closed, external gas cannot enter from the top of the first three-way T-ball valve 208. When the left and right sides of the second three-way T-ball valve 3 are open and the bottom is closed, the entire pipeline exhausts normally.

[0052] Furthermore, such as Figure 1-10As shown, a filter tube 305 is fixedly embedded in the inner wall of the second three-way T-type ball valve 3 near the right side. A stainless steel sintered mesh 308 is fixedly embedded in the inner wall of the filter tube 305. An oil-blocking and venting membrane 307 is fixedly connected to the right side of the stainless steel sintered mesh 308, and a stainless steel mesh 306 is fixedly connected to the right side of the oil-blocking and venting membrane 307. During venting, oil or gas enters the interior of the filter tube 305, first passes through the stainless steel mesh 306, and then passes through the oil-blocking and venting membrane 307 and the stainless steel sintered mesh 308 for oil blocking and venting. The stainless steel mesh 306 can filter out large particles of impurities first, which has a protective effect on the oil-blocking and venting membrane 307. During oil blocking and venting, large particles are filtered first, and large particles will not impact the oil-blocking and venting membrane 307, preventing oil blockage. The breathable membrane 307 is damaged by impact from large particles. The oil-blocking and breathable membrane 307 is a microporous membrane made of polytetrafluoroethylene through calendering, extrusion, and biaxial stretching. It has the characteristics of high air permeability, uniform pore size distribution, and resistance to damage. After being treated with superoleophobic material, it can achieve oil-blocking and breathable functions, separating oil and gas. The stainless steel sintered mesh 308 is made of multiple layers of stainless steel wire mesh through special lamination and vacuum sintering. It has the characteristics of high mechanical strength and high filtration accuracy. It is mainly used to supplement the oil-blocking and breathable function of the oil-blocking and breathable membrane 307 and increase the mechanical strength of the entire oil-blocking and breathable structure. The stainless steel mesh 306, the oil-blocking and breathable membrane 307, and the stainless steel sintered mesh 308 are combined together through the filter tube 305 to form an oil-blocking and breathable structure.

[0053] Furthermore, such as Figure 1-10 As shown, a two-way ball valve 4 is fixedly connected to the top of the second three-way T-type ball valve 3. An air inlet pipe 401 is fixedly connected to the top of the two-way ball valve 4. A waterproof ventilated membrane 402 is fixedly connected to the top of the air inlet pipe 401. A waterproof air inlet cap 403 is threadedly connected to the inner wall of the waterproof ventilated membrane 402 near the top. The threaded installation method makes the entire waterproof and breathable device easy to install. The addition of a two-way ball valve 4 to the air inlet pipe 401, including the waterproof air inlet cap 403 and the waterproof ventilated membrane 402, prevents atmospheric particles and liquids from entering the pipeline through the air inlet cap, achieving the functions of waterproofing, dustproofing, and preventing contamination of oil quality. Therefore, this structure can be used in outdoor environments.

[0054] Furthermore, such as Figure 1-10 As shown, a protective cover 404 is fixedly connected to the top of the waterproof air inlet cap 403. A breathable membrane 407 is fixedly connected to the inner wall of the protective cover 404. The protective cover 404 provides protection for the breathable membrane 407 to prevent damage to the breathable membrane and affect its function.

[0055] Furthermore, such as Figure 1-10As shown, a silicone ring 406 is fixedly fitted on the outer surface of the protective cover 404 near the bottom. Ventilation holes 405 are opened on both sides of the protective cover 404 near the top. The breathable membrane 407 is made of polytetrafluoroethylene. The polytetrafluoroethylene 407 has the characteristics of large air permeability, uniform pore size distribution and not easy to break. After being treated with super oleophobic material, it achieves oil-blocking and breathable functions.

[0056] Furthermore, such as Figure 1-10 As shown, filter 1 has oil outlets at both the top and bottom.

[0057] Working principle: By opening the pressure relief valve 201 on the pressure relief pipe 2, the filter 1 can be depressurized. The internal pressure of the filter 1 is as high as 0.8 MPa. When there is gas inside the filter 1, the entire exhaust pipeline exhausts normally. The gas enters the exhaust valve 203 through the through hole at the bottom of the exhaust valve 203. At this time, under the action of the gas, the oil-blocking float 207 floats up, opening the switch of the exhaust valve 203, allowing the exhaust valve 203 to exhaust. Then, the gas enters the first exhaust pipe 204 through the through hole at the top of the exhaust valve 203. The eccentric impeller sight glass 205 can simultaneously observe the exhaust and intake effects. It can increase the cross-sectional area of ​​the pipeline, and the eccentricity increases the buffer, reducing the impact of sudden pressure increases such as water hammer. It can also observe whether the exhaust valve 203 has internal leakage and the amount of internal leakage. Three-way ball valve It can rotate 360 ​​degrees. By controlling the different opening modes of the first three-way T-type ball valve 208 and the second three-way T-type ball valve 3, it can be used for different situations. When the left and right sides of the first three-way T-type ball valve 208 are open and the top is closed, external gas cannot enter from the top of the first three-way T-type ball valve 208. When the left and right sides of the second three-way T-type ball valve 3 are open and the bottom is closed, the entire pipeline is normally vented. The main ball valve 209 is normally open, and the venting pipeline can normally vent through the oil-blocking and venting structure on the right side of the second three-way T-type ball valve 3. During venting, oil or gas enters the interior of the filter pipe 305, first passes through the stainless steel mesh 306, and then through the oil-blocking and venting membrane 307 and the stainless steel sintered mesh 308 for oil blocking and venting. The stainless steel mesh 306 can filter out large particles of impurities first, which also protects the oil-blocking and venting membrane 307.During oil blocking and venting, large particles are filtered first. These large particles will not impact the oil-blocking and breathable membrane 307, preventing damage. The oil-blocking and breathable membrane 307 is a microporous membrane made of polytetrafluoroethylene through calendering, extrusion, and biaxial stretching. It features high air permeability, uniform pore size distribution, and resistance to breakage. After being treated with a superoleophobic coating, it achieves oil blocking and breathability, effectively separating oil and gas. The stainless steel sintered mesh 308 is made of multiple layers of stainless steel wire mesh through special lamination and vacuum sintering. It features high mechanical strength and high filtration accuracy, and is mainly used for oil blocking and venting. To supplement the oil-blocking and breathable function of the gas membrane 307 and increase the mechanical strength of the entire oil-blocking and breathable structure, the stainless steel mesh 306, the oil-blocking and breathable membrane 307, and the stainless steel sintered mesh 308 are combined through the filter pipe 305 to form an oil-blocking and breathable structure. When the oil-blocking and breathable structure is blocked or cannot block oil normally, the right side of the second three-way T-ball valve 3 is closed, and the gas is discharged into the underground tank 303 through the branch pipe 301 at the bottom of the second three-way T-ball valve 3. The gas is discharged into the underground tank 303 through the filter 1 via the first exhaust pipe 204 and the second exhaust pipe 302. When it is necessary for the filter 1 to drain oil smoothly, the first three-way T-ball valve 204 is closed. With the right side of valve 08 closed and the top and left sides open, external gas can enter the filter 1 through the top of the protective cover 404 via the two-way ball valve 4 and the first exhaust pipe 204, thus cleaning the filter 1 by draining oil. A separate intake pipe, namely the two-way ball valve 4, is added to prevent backflow of oil. By closing the main ball valve 209, the entire exhaust pipe can be shut off, allowing for maintenance and inspection of components on the pipe, such as replacing the eccentric impeller sight glass 205. The combination of two sets of three-way ball valves enables switching between the intake and exhaust pipes, a simple, time-saving, and labor-saving method that also enhances the exhaust structure. The device boasts diverse performance characteristics. By adding a two-way ball valve 4, it achieves a dual-valve effect with the first three-way T-type ball valve 208. This eliminates the need for frequent plug installation at the air inlet, avoiding the inconvenience of frequent plug removal and installation when air intake is required. A two-way ball valve 4 is added to the air intake pipe 401, including a waterproof air intake cap 403 and a waterproof vent membrane 402. Through the vent hole in the protective cover 404, air can be introduced and exhausted, while preventing atmospheric particles and liquids from entering the pipeline through the air intake cap. The threaded connection between the waterproof air intake cap 403 and the air intake pipe 401 makes installation convenient and simple, improving practical applicability. It achieves waterproof and dustproof protection, preventing oil contamination, thus making this structure suitable for outdoor environments.

[0058] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments for application in other fields. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A filter exhaust structure for an airport oil depot, characterized in that, include: Filter (1); A pressure relief pipe (2) is fixedly installed at the bottom of the filter (1), and a pressure relief valve (201) is fixedly installed at the center of the outer surface of the pressure relief pipe (2); a first connecting pipe (202) is fixedly installed at the center of the top of the pressure relief pipe (2), and an exhaust valve (203) is fixedly installed at the top of the first connecting pipe (202); An oil-blocking float (207) is movably connected to the inner wall at the bottom of the exhaust valve (203); First exhaust pipe (204); An eccentric impeller sight glass (205) is fixedly installed at one end of the first exhaust pipe (204), and the other end of the eccentric impeller sight glass (205) is fixedly connected to a second connecting pipe (206); The first three-way T-type ball valve (208) is fixedly installed at the other end of the second connecting pipe (206); The main ball valve (209) is fixedly installed on the top of the first exhaust pipe (204); A second three-way T-type ball valve (3) is fixedly installed on the right side of the first three-way T-type ball valve (208). A second exhaust pipe (302) is fixedly connected to the right side of the second three-way T-type ball valve (3). The other end of the second exhaust pipe (302) is fixedly connected to a buried tank (303). An oil outlet pipe (304) is fixedly connected to the top of the buried tank (303). The second three-way T-type ball valve (3) has a filter tube (305) fixedly embedded on the inner wall near the right side. The filter tube (305) has a stainless steel sintered mesh (308) fixedly embedded on the inner wall. The stainless steel sintered mesh (308) has an oil-blocking and breathable membrane (307) fixedly connected to the right side. The oil-blocking and breathable membrane (307) has a stainless steel mesh (306) fixedly connected to the right side. The top of the second three-way T-type ball valve (3) is fixedly connected to a two-way ball valve (4), the top of the two-way ball valve (4) is fixedly connected to an air inlet pipe (401), the top of the air inlet pipe (401) is fixedly connected to a waterproof venting membrane (402), and the inner wall of the waterproof venting membrane (402) near the top is threaded with a waterproof air inlet cap (403).

2. The filter exhaust structure for an airport oil depot according to claim 1, characterized in that: The exhaust valve (203) has exhaust ports on the inner walls of its top and bottom that match the oil-blocking float (207).

3. The filter exhaust structure for an airport oil depot according to claim 1, characterized in that: The bottom of the second three-way T-type ball valve (3) is fixedly installed with a branch pipe (301), and the other end of the branch pipe (301) is fixedly connected to the center of the bottom of the second exhaust pipe (302).

4. The filter exhaust structure for an airport oil depot according to claim 1, characterized in that: The top of the waterproof air inlet cap (403) is fixedly connected to a protective cover (404), and the inner wall of the protective cover (404) is fixedly connected to a breathable membrane (407).

5. The filter exhaust structure for an airport oil depot according to claim 4, characterized in that: The protective cover (404) has a silicone ring (406) fixedly fitted on the outer surface near the bottom. Ventilation holes (405) are opened on both sides near the top of the protective cover (404). The material of the breathable film (407) is polytetrafluoroethylene.

6. The filter exhaust structure for an airport oil depot according to claim 1, characterized in that: The filter (1) has oil outlets at both the top and bottom.

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