阅读说明：本技术 一种油舱透气系统及海洋船舶 (Oil tank ventilation system and marine ship ) 是由 周明娇 于 2021-11-15 设计创作，主要内容包括：本发明公开了一种油舱透气系统及海洋船舶,包括：第一回收油舱,通过第一连接管路与海洋船舶油舱连接；第一透气管,第一透气管的下端与第一回收油舱的上端连接,第一透气管的上端设置有第一弯头部；第二透气管,呈U形,第二透气管的一端与第一弯头部连接形成倒U形结构；第三透气管,第三透气管的上端设置有第二弯头部,第二弯头部与第二透气管的另一端连接形成倒U形结构,第三透气管的下端设置有排气控制结构；第二回收油舱,通过第二连接管路与第二透气管的底部连接；该油舱透气系统具有第一回收油舱和第二回收油舱,分别能够回收海洋船舶油舱排出的携带油气的气体行程的冷凝油和回收在排气控制结构处冷凝或掺杂了少量海水的油水混合物。(The invention discloses an oil tank ventilation system and a marine ship, comprising: the first recovery oil tank is connected with the oil tank of the marine vessel through a first connecting pipeline; the lower end of the first vent pipe is connected with the upper end of the first recovery oil tank, and a first elbow part is arranged at the upper end of the first vent pipe; the second vent pipe is U-shaped, and one end of the second vent pipe is connected with the first elbow part to form an inverted U-shaped structure; the upper end of the third vent pipe is provided with a second elbow part, the second elbow part is connected with the other end of the second vent pipe to form an inverted U-shaped structure, and the lower end of the third vent pipe is provided with an exhaust control structure; the second recovery oil tank is connected with the bottom of the second vent pipe through a second connecting pipeline; the oil tank ventilation system is provided with a first recovery oil tank and a second recovery oil tank, and can recover condensed oil which is discharged from the oil tank of the marine vessel and carries the gas travel of oil gas and recover oil-water mixture condensed or doped with a small amount of seawater at an exhaust control structure.)

1. A tank breathing system, characterized in that it comprises:

the first recovery oil tank is connected with the oil tank of the marine vessel through a first connecting pipeline;

the lower end of the first vent pipe is connected with the upper end of the first recovery oil tank, and a first elbow part is arranged at the upper end of the first vent pipe;

the second vent pipe is U-shaped, and one end of the second vent pipe is connected with the first elbow part to form an inverted U-shaped structure;

the upper end of the third vent pipe is provided with a second elbow part, the second elbow part is connected with the other end of the second vent pipe to form an inverted U-shaped structure, and the lower end of the third vent pipe is provided with an exhaust control structure;

and the second recovery oil tank is connected with the bottom of the second vent pipe through a second connecting pipeline.

2. The tank ventilation system according to claim 1, wherein the first ventilation tube is vertically arranged, a plurality of heat exchange fins are arranged on the wall of the first ventilation tube, one end of each heat exchange fin is arranged inside the first ventilation tube, and the other end of each heat exchange fin is arranged outside the first ventilation tube.

3. The tank ventilation system according to claim 2, wherein the heat exchanger fins are uniformly distributed along the circumference of the first ventilation tube, a cavity is formed inside each heat exchanger fin, heat conducting liquid is arranged in each cavity, and one end of each heat exchanger fin, which is positioned inside the first ventilation tube, is lower than one end of each heat exchanger fin, which is positioned outside the first ventilation tube.

4. The tank venting system of claim 3 wherein said second recovery tank is nested outside said first breather tube and said heat exchanger fins are located within said second recovery tank.

5. The tank breathing system according to claim 1, wherein the first connection line comprises an exhaust pipe and a return pipe, one end of the exhaust pipe is connected with the top of the marine vessel tank, the other end of the exhaust pipe is arranged inside the first recovery tank in a penetrating manner, and two ends of the return pipe are respectively connected with the top of the marine vessel tank and the bottom of the first recovery tank; the other end of the exhaust pipe penetrates into the upper side of the interior of the first recovery oil tank, a first valve is arranged on the return pipe, and a first liquid level meter is arranged in the first recovery oil tank.

6. The tank breathing system of claim 1 wherein a second level gauge is provided in the second recovery tank, and wherein a drain is provided at the bottom of the second recovery tank, the drain having a second valve disposed thereon.

7. The cargo tank breathing system of claim 1 wherein said vent control structure comprises:

the sealing plate is arranged in the third air-permeable pipe, and a first air hole is formed in the middle of the sealing plate;

the sealing block is arranged in the third air pipe in a sliding mode, and a semicircular sealing part is arranged on one side, close to the sealing plate, of the sealing block;

the elastic component is arranged on one side, far away from the sealing plate, of the sealing block, the lower end of the elastic component is fixed on the third vent pipe through a support, and the elastic component can push the sealing block to move towards the direction close to the sealing plate and seal the first air hole through the sealing part;

and the second air hole is formed in the pipe wall of the third vent pipe and is positioned between the sealing plate and the sealing block.

8. The tank venting system of claim 7 wherein the lower end of said third vent tube is connected to said second recovery tank by a third connecting line.

9. A marine vessel comprising a tank ventilation system according to any one of claims 1-8.

10. The marine vessel of claim 9, wherein the first recovery tank is disposed below a deck of the marine vessel, the second recovery tank is disposed above the deck, and the first gas permeable tube penetrates the deck.

Technical Field

The invention belongs to the technical field of marine ships, and particularly relates to an oil tank ventilation system and a marine ship.

Background

In order to ensure the maximum cruising power of the marine vessel during navigation, the oil storage capacity of the oil tank of the marine vessel is increased more and more. Because of thermal expansion and cold contraction or jolt of the ship, the oil in the oil tank can be quickly volatilized, the pressure of the oil tank is gradually increased, and the hidden danger of explosion is caused. In order to avoid excessive pressure in the cargo tank, a vent pipe is usually installed on the marine vessel cargo tank; the permeability cell directly stretches out from the cabin top, extends to the height required by the specification, and a permeability tube head is arranged at the top and has a one-way non-return function, so that the normal permeability of the cabin is ensured, and external seawater, pollutants and the like are prevented from being mixed into the fuel oil cabin. The existing vent pipe is simple in design and single in function, external seawater, water vapor and the like cannot enter the oil tank easily, and the quality of oil is reduced. In addition, heavy fuel oil is used in general large ships, and a steam heating coil is arranged in an oil tank to heat the fuel oil, so that the permeated gas contains a large amount of oil, and the gas with the oil is easy to form condensed oil after being sprayed out when being discharged, so that the ships or seawater are polluted, and the environmental protection requirement is difficult to meet.

Disclosure of Invention

The invention aims to provide an oil tank ventilating system and a marine vessel aiming at the defects in the prior art, the oil tank ventilating system is provided with a first recovery oil tank and a second recovery oil tank, condensed oil carrying gas strokes of oil gas discharged by the marine vessel oil tank can be recovered, oil-water mixture condensed or doped with a small amount of seawater at an exhaust control structure can be recovered, and the first ventilating pipe, the second ventilating pipe and the third ventilating pipe are structurally designed, so that external seawater or water vapor is prevented from entering the marine vessel oil tank.

In order to achieve the above object, the present invention provides a tank ventilation system, comprising:

the first recovery oil tank is connected with the oil tank of the marine vessel through a first connecting pipeline;

the lower end of the first vent pipe is connected with the upper end of the first recovery oil tank, and a first elbow part is arranged at the upper end of the first vent pipe;

the second vent pipe is U-shaped, and one end of the second vent pipe is connected with the first elbow part to form an inverted U-shaped structure;

the upper end of the third vent pipe is provided with a second elbow part, the second elbow part is connected with the other end of the second vent pipe to form an inverted U-shaped structure, and the lower end of the third vent pipe is provided with an exhaust control structure;

and the second recovery oil tank is connected with the bottom of the second vent pipe through a second connecting pipeline.

Optionally, the first vent pipe is vertically arranged, a plurality of heat exchange fins penetrate through a pipe wall of the first vent pipe, one end of each heat exchange fin is located inside the first vent pipe, and the other end of each heat exchange fin is arranged outside the first vent pipe.

Optionally, the heat exchange fins are uniformly distributed along the circumferential direction of the first vent pipe, a cavity is formed in the heat exchange fins, heat conducting liquid is arranged in the cavity, and one end, located inside the first vent pipe, of each heat exchange fin is lower than one end, located outside the first vent pipe, of each heat exchange fin.

Optionally, the second recycling oil bin is sleeved outside the first vent pipe, and the heat exchange fins are located in the second recycling oil bin.

Optionally, the first connecting pipeline includes an exhaust pipe and a return pipe, one end of the exhaust pipe is connected to the top of the marine vessel cargo tank, the other end of the exhaust pipe is arranged inside the first recovery cargo tank in a penetrating manner, and two ends of the return pipe are respectively connected to the top of the marine vessel cargo tank and the bottom of the first recovery cargo tank; the other end of the exhaust pipe penetrates into the upper side of the interior of the first recovery oil tank, a first valve is arranged on the return pipe, and a first liquid level meter is arranged in the first recovery oil tank.

Optionally, a second liquid level meter is arranged in the second recovery oil tank, a discharge pipe is arranged at the bottom of the second recovery oil tank, and a second valve is arranged on the discharge pipe.

Optionally, the exhaust gas control structure includes:

the sealing plate is arranged in the third air-permeable pipe, and a first air hole is formed in the middle of the sealing plate;

the sealing block is arranged in the third air pipe in a sliding mode, and a semicircular sealing part is arranged on one side, close to the sealing plate, of the sealing block;

the elastic component is arranged on one side, far away from the sealing plate, of the sealing block, the lower end of the elastic component is fixed on the third vent pipe through a support, and the elastic component can push the sealing block to move towards the direction close to the sealing plate and seal the first air hole through the sealing part;

and the second air hole is formed in the pipe wall of the third vent pipe and is positioned between the sealing plate and the sealing block.

Optionally, the lower end of the third ventilation pipe is connected with the second recovery oil tank through a third connecting pipeline.

The invention also provides a marine vessel comprising the oil tank ventilation system.

Optionally, the first recovery tank is disposed below a deck of the marine vessel, the second recovery tank is disposed above the deck, and the first gas permeable tube penetrates the deck.

The invention provides an oil tank ventilation system and a marine ship, which have the beneficial effects that:

1. the oil tank ventilation system is provided with a first recovery oil tank and a second recovery oil tank, and can recover condensed oil which is discharged from the oil tank of the marine vessel and carries the gas travel of oil gas and recover an oil-water mixture which is condensed or doped with a small amount of seawater at an exhaust control structure respectively;

2. the oil tank ventilation system can effectively prevent external seawater or water vapor from entering the oil tank of the marine vessel through the structural design of the first ventilation pipe, the second ventilation pipe and the third ventilation pipe;

3. according to the oil tank ventilation system, the heat exchange fins are arranged on the first ventilation pipe, so that the condensation effect of oil gas in the first ventilation pipe is improved, and the recovery of clean condensed oil is facilitated;

4. the heat exchange fins of the oil tank ventilation system can form heat pipes, and the heat exchange fins are located outside the second recovery oil tank, so that the heat exchange fins can be protected, and the heat exchange effect can be improved.

Additional features and advantages of the invention will be set forth in the detailed description which follows.

Drawings

The above and other objects, features and advantages of the present invention will become more apparent by describing in more detail exemplary embodiments thereof with reference to the attached drawings, in which like reference numerals generally represent like parts throughout.

Fig. 1 shows a schematic structural view of a tank ventilation system according to an embodiment of the present invention.

Fig. 2 shows a schematic cross-sectional structural view of a first gas permeable tube of a tank ventilation system according to an embodiment of the invention.

Fig. 3 shows a schematic view of an exhaust gas control structure of a cargo tank ventilation system according to an embodiment of the present invention.

Description of reference numerals:

1. a first recovery tank; 2. a marine vessel tank; 3. a first gas permeable tube; 4. a first elbow portion; 5. a second gas permeable tube; 6. a third gas permeable tube; 7. a second elbow portion; 8. an exhaust control structure; 9. a second recovery tank; 10. a heat exchanger fin; 11. an exhaust pipe; 12. a return pipe; 13. a discharge pipe; 14. closing the plate; 15. a first air hole; 16. sealing blocks; 17. an elastic member; 18. a second air hole; 19. a third connecting pipeline; 20. the deck.

Detailed Description

Preferred embodiments of the present invention will be described in more detail below. While the following describes preferred embodiments of the present invention, it should be understood that the present invention may be embodied in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

The invention provides an oil tank ventilation system, which comprises:

the first recovery oil tank is connected with the oil tank of the marine vessel through a first connecting pipeline;

the lower end of the first vent pipe is connected with the upper end of the first recovery oil tank, and a first elbow part is arranged at the upper end of the first vent pipe;

the second vent pipe is U-shaped, and one end of the second vent pipe is connected with the first elbow part to form an inverted U-shaped structure;

the upper end of the third vent pipe is provided with a second elbow part, the second elbow part is connected with the other end of the second vent pipe to form an inverted U-shaped structure, and the lower end of the third vent pipe is provided with an exhaust control structure;

and the second recovery oil tank is connected with the bottom of the second vent pipe through a second connecting pipeline.

Specifically, the first recovery oil tank and the second recovery oil tank are respectively used for recovering clean condensed oil and unclean condensed oil, after gas containing oil gas is discharged from the marine vessel oil tank, the gas is firstly condensed in the first vent pipe, the first vent pipe is vertically arranged, the condensed clean condensed oil can flow back to the first recovery oil tank for recovery, and can be continuously returned to the marine vessel oil tank for use as standby oil after recovery, so that the waste of oil is reduced, the oil gas content in the gas is removed in the process, and the environment is protected; in the second ventilation pipe, gas can be further condensed, the condensed oil flows to the lowest point of the second ventilation pipe due to the U-shaped second ventilation pipe, and one side of the second ventilation pipe close to the third ventilation pipe possibly enters a little water vapor or seawater due to the exhaust of the exhaust control structure on the third ventilation pipe, so that one side of the second ventilation pipe close to the third ventilation pipe possibly condenses into unclean oil drops containing seawater or water, and the unclean condensed oil flows into the second recovery oil chamber through the second connecting pipeline for recovery, so that the oil gas content in the gas is further removed, the unclean condensed oil can be recovered, and the unclean condensed oil can be recycled after being processed; like this, the gas of exhaust control structure combustion gas through on the third permeability cell is just very clean, can satisfy the environmental protection requirement to the third permeability cell is vertical arrangement also, and the lower extreme exhaust can reduce the entering of sea water or steam, further avoids first recovery oil tank and marine vessel oil tank to be polluted.

Optionally, the first vent pipe is vertically arranged, a plurality of heat exchange fins penetrate through the wall of the first vent pipe, one end of each heat exchange fin is located inside the first vent pipe, and the other end of each heat exchange fin is arranged outside the first vent pipe.

Specifically, such setting up of heat exchanger fin can improve the oil gas condensation effect in first breathing pipe in the gas, improves the clearance of oil gas in first breathing pipe, avoids a large amount of oil gas to discharge into the atmosphere.

Optionally, the heat exchanger fins are uniformly distributed along the circumferential direction of the first vent pipe, a cavity is formed in the heat exchanger fins, heat conducting liquid is arranged in the cavity, and one end, located inside the first vent pipe, of each heat exchanger fin is lower than one end, located outside the first vent pipe, of each heat exchanger fin.

Specifically, the design that the plurality of heat exchange plates are uniformly distributed along the circumferential direction of the first ventilating pipe enables one end, positioned inside the first ventilating pipe, of the plurality of heat exchange plates to form a grid-shaped structure on one cross section, and condensation of oil gas when the gas passes through the grid-shaped structure in the flowing process of the gas is facilitated; moreover, the heat-conducting liquid in the heat exchange plate is gasified when being heated, flows to one end positioned at the outer side of the first vent pipe, is condensed and then flows back to form a simple heat pipe, so that the temperature of the heat exchange plate positioned in the first vent pipe can always meet the condensing requirement, and the condensing effect is ensured; the slope of heat exchanger fin sets up the downflow that is favorable to the condensate oil simultaneously, compares in a large amount of liquid drops and attaches to the condensation of being unfavorable for the oil gas in the first permeability cell on the inner wall of first permeability cell, and such design also can improve condensation effect.

Optionally, the second recycling oil tank is sleeved outside the first vent pipe, and the heat exchange fins are located in the second recycling oil tank.

Specifically, the first vent pipe penetrates through the second recovery oil tank, and unclean condensed oil recovered from the second recovery oil tank soaks the part of the heat exchange fin, which is positioned outside the first vent pipe, so that a cold source is provided, the heat exchange efficiency of the heat exchange fin is improved, and the condensation effect in the first vent pipe is improved; and can protect first permeability cell, avoid its slim structural feature and expose on the deck, damage because of colliding with easily, also can save the reinforcement or the protection facility to first permeability cell from another angle.

Optionally, the first connecting pipeline comprises an exhaust pipe and a return pipe, one end of the exhaust pipe is connected with the top of the marine vessel cargo tank, the other end of the exhaust pipe penetrates through the first recovery cargo tank, and two ends of the return pipe are respectively connected with the top of the marine vessel cargo tank and the bottom of the first recovery cargo tank; the other end of the exhaust pipe penetrates into the upper side of the interior of the first recovery oil tank, a first valve is arranged on the return pipe, and a first liquid level meter is arranged in the first recovery oil tank.

Specifically, the other end of the exhaust pipe extends into the first recovered oil tank to a higher height than the liquid level in the first recovered oil tank, so that the reliability of the exhaust of the marine vessel oil tank can be ensured, and meanwhile, the exhaust pipe is not directly connected to the first vent pipe, so that the oil splashed in the marine vessel oil tank during bumping cannot directly enter the first vent pipe and falls into the first recovered oil tank filled with clean condensed oil; and the liquid level in first recovery oil tank is monitored to first level gauge, conveniently controls first valve and in time carries out the backward flow utilization of recovered oil, and at this in-process, the intercommunication of blast pipe and first recovery oil tank upper portion gas space for when the oil in the first recovery oil tank discharges after first valve is opened, first recovery oil tank upper portion can not form the low atmospheric pressure and lead to the oil extraction not smooth.

In one example, the top of the first recovery tank and the top of the second recovery tank may be provided with an air inlet valve, which can be used for air inlet when oil is drained.

Optionally, a second liquid level meter is arranged in the second recovery oil tank, a discharge pipe is arranged at the bottom of the second recovery oil tank, and a second valve is arranged on the discharge pipe.

Specifically, the liquid level in the second recovery oil tank can be monitored by the second liquid level meter, and all heat exchange fins immersed as much as possible in the liquid level are ensured to be positioned in the outer part of the first vent pipe, so that the heat exchange effect is improved, and when the liquid level is too high, the second valve can be opened to discharge oil, so that the liquid level in the second recovery oil tank can be maintained within a stable range.

Optionally, the exhaust gas control structure includes:

the sealing plate is arranged in the third air pipe, and a first air hole is formed in the middle of the sealing plate;

the sealing block is arranged in the third air pipe in a sliding mode, and a semicircular sealing part is arranged on one side, close to the sealing plate, of the sealing block;

the elastic component is arranged on one side, away from the sealing plate, of the sealing block, the lower end of the elastic component is fixed on the third vent pipe through a support, and the elastic component can push the sealing block to move towards the direction close to the sealing plate and plug the first air hole through the sealing part;

and the second air hole is formed in the pipe wall of the third vent pipe and is positioned between the sealing plate and the sealing block.

Specifically, the exhaust of the exhaust control structure is arranged downwards, so that rainwater or splashed seawater can be effectively prevented from entering, when the gas pressure is high enough and the exhaust is needed, the gas overcomes the elasticity of the elastic part to push the sealing block to move, the first air hole is opened, the gas is discharged downwards after passing through the vertical third vent pipe, and even if a small amount of oil drops exist in the gas, the oil drops can flow downwards and cannot be discharged from the second air hole in the side wall of the third vent pipe, so that the clean gas is discharged through the second air hole, the pressure relief is realized, and the environment-friendly requirement is met; it should be noted that neither the seal nor the seal block need seal against the inner wall of the third permeability cell, as long as a guide is formed.

Optionally, the lower end of the third ventilation pipe is connected with the second recovery oil tank through a third connecting pipeline.

Specifically, the third connecting pipeline can guide a small amount of oil drops discharged from the first air hole into the second recovery oil tank, so that the oil drops are prevented from dropping on a deck or seawater to cause pollution.

The invention also provides a marine vessel comprising the oil tank ventilation system.

Optionally, the first recovery tank is disposed below a deck of the marine vessel, the second recovery tank is disposed above the deck, and the first gas permeable tube penetrates the deck.

Specifically, the first recovery oil tank is arranged below the deck, so that excessive upper space of the deck is not occupied, automatic control is conveniently carried out through the arrangement of the first liquid level meter and the first valve, and manual operation is not needed; the second recovery oil tank is arranged above the deck and is in contact with media such as air, seawater and the like, heat dissipation is facilitated, the exposed part of the first vent pipe and the part on the deck are protected, and unclean condensed oil in the second recovery oil tank is convenient to discharge.

Examples

As shown in fig. 1 to 3, the present invention provides a tank ventilation system, which includes:

the first recovery oil tank 1 is connected with the marine oil tank 2 through a first connecting pipeline;

the lower end of the first vent pipe 3 is connected with the upper end of the first recovery oil tank 1, and a first elbow part 4 is arranged at the upper end of the first vent pipe 3;

the second ventilation pipe 5 is U-shaped, and one end of the second ventilation pipe 5 is connected with the first elbow part 4 to form an inverted U-shaped structure;

a second elbow part 7 is arranged at the upper end of the third vent pipe 6, the second elbow part 7 is connected with the other end of the second vent pipe 5 to form an inverted U-shaped structure, and an exhaust control structure 8 is arranged at the lower end of the third vent pipe 6;

and the second recovery oil tank 9 is connected with the bottom of the second vent pipe 5 through a second connecting pipeline.

In this embodiment, the first ventilation pipe 3 is vertically arranged, the plurality of heat exchange fins 10 penetrate through the wall of the first ventilation pipe 3, one end of each heat exchange fin 10 is located inside the first ventilation pipe 3, and the other end of each heat exchange fin 10 is arranged outside the first ventilation pipe 3.

In this embodiment, the heat exchanger fins 10 are uniformly distributed along the circumferential direction of the first ventilation pipe 3, a cavity is formed inside the heat exchanger fins 10, heat conducting liquid is provided in the cavity, and one end of the heat exchanger fins 10 inside the first ventilation pipe 3 is lower than one end of the heat exchanger fins 10 outside the first ventilation pipe 3.

In this embodiment, the second recovery oil tank 9 is sleeved outside the first ventilation pipe 3, and the heat exchange fins 10 are located in the second recovery oil tank 9.

In this embodiment, the first connection pipeline includes an exhaust pipe 11 and a return pipe 12, one end of the exhaust pipe 11 is connected to the top of the marine vessel cargo tank 2, the other end of the exhaust pipe 11 is inserted into the first recovery cargo tank 1, and two ends of the return pipe 12 are respectively connected to the top of the marine vessel cargo tank 2 and the bottom of the first recovery cargo tank 1; the other end of the exhaust pipe 11 penetrates into the upper side of the interior of the first recovery oil tank 1, a first valve is arranged on the return pipe 12, and a first liquid level meter is arranged in the first recovery oil tank 1.

In this embodiment, a second liquid level meter is arranged in the second recovery oil tank 9, a discharge pipe 13 is arranged at the bottom of the second recovery oil tank 9, and a second valve is arranged on the discharge pipe 13.

In the present embodiment, the exhaust gas control structure 8 includes:

the sealing plate 14 is arranged in the third vent pipe 6, and a first air hole 15 is formed in the middle of the sealing plate 14;

the sealing block 16 is arranged in the third vent pipe 6 in a sliding mode, and a semicircular sealing part is arranged on one side, close to the sealing plate 14, of the sealing block 16;

the elastic component 17 is arranged on one side of the sealing block 16, which is far away from the sealing plate 14, the lower end of the elastic component 17 is fixed on the third vent pipe 6 through a bracket, and the elastic component 17 can push the sealing block 16 to move towards the direction close to the sealing plate 14 and seal the first air hole 15 through a sealing part;

and the second air hole 18 is formed in the wall of the third ventilation pipe 6, and the second air hole 18 is formed between the sealing plate 14 and the sealing block 16.

In this embodiment, the lower end of the third permeability tube 6 is connected to the second recovery tank 9 via a third connecting line 19.

The invention also provides a marine vessel comprising the oil tank ventilation system.

In this embodiment, the first recovery tank 1 is disposed below the deck 20 of the marine vessel, the second recovery tank 9 is disposed above the deck 20, and the first permeability tube 3 penetrates the deck 20.

In summary, when the oil tank ventilation system provided by the invention is used, gas in the marine vessel oil tank 2 enters the first recovery oil tank 1 through the exhaust pipe 11 and is discharged into the first ventilation pipe 3 through the top of the first recovery oil tank 1, the gas is effectively condensed under the action of the heat exchange fins 10 when passing through the first ventilation pipe 3, so as to form clean condensed oil, and the clean condensed oil can flow back into the first recovery oil tank 1, and the clean condensed oil in the first recovery oil tank 1 can flow back to the marine vessel oil tank 2 through the return pipe 12 as needed, so as to realize recycling; in the condensation process, the heat exchange fins 10 form heat pipes, the part in the first ventilation pipe 3 is a heat absorption end, the part in the second recovery oil tank 9 is a heat release end, and heat exchange is ceaselessly performed to ensure the condensation effect of oil gas and simultaneously utilize unclean oil in the second recovery oil tank 9. The gas that passes through first permeability cell 3 gets into second permeability cell 5, and second permeability cell 5 is the U-shaped, no matter be the unclean steam or the sea water that get into in the third permeability cell 6, still the oil droplet of condensation in second permeability cell 5, all can flow downwards in second permeability cell 5, flow into the second through the second connecting line and retrieve in the oil tank 9, avoid mixing the unclean condensate oil that has the sea water and flow back to first permeability cell 3, pollute clean condensate oil. The gas passes through the second permeability cell 5 and then is discharged through the exhaust control structure 8 on the third permeability cell 6, the gas in the third permeability cell 6 is relatively clean, when the pressure is sufficient, the gas overcomes the elasticity of the elastic component 17, the sealing part is pushed to open the first air hole 15, the gas passes through the first air hole 15 and then is discharged through the second air hole 18, the second air hole 18 is positioned on the side wall of the third permeability cell 6, the gas passing through the first air hole 15 flows downwards, even if a small amount of oil drops flow out, the gas cannot be discharged from the second air hole 18, but can flow downwards to the second recovery oil tank 9 through the third connecting pipeline 19; in this way, the gas discharged from the second air hole 18 can meet the environmental requirement, and after the pressure is discharged, the elastic component 17 enables the sealing block 16 to reset, and the sealing part seals the first air hole 15 again. The system is provided with two kinds of recovery oil tanks, gas discharged from the oil tank of the marine ship is condensed by two pipelines of the first vent pipe 3 and the second vent pipe 5, clean condensed oil and unclean condensed oil are recovered respectively, and the gas discharged to the atmosphere meets the requirement of environmental protection.

Having described embodiments of the present invention, the foregoing description is intended to be exemplary, not exhaustive, and not limited to the embodiments disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments.